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| 1 | Carcinoma of the stomach: A review of epidemiology, pathogenesis, molecular genetics and chemoprevention显示文摘Carcinoma of the stomach is still the second most common cause of cancer death worldwide, although the incidence and mortality have fallen dramatically over the last 50 years in many regions. The incidence of gastric cancer varies in different parts of the world and among various ethnic groups. Despite advances in diagnosis and treatment, the 5-year survival rate of stomach cancer is only 20 per cent. Stomach cancer can be classified into intestinal and diffuse types based on epidemiological and clinicopathological features. The etiology of gastric cancer is multifactorial and includes both dietary and nondietary factors. The major diet-related risk factors implicated in stomach cancer development include high content of nitrates and high salt intake. Accumulating evidence has implicated the role of Helicobacter pylori (H. pylori) infection in the pathogenesis of gastric cancer. The development of gastric cancer is a complex, multistep process involving multiple genetic and epigenetic alterations of oncogenes, tumor suppressor genes, DNA repair genes, cell cycle regulators, and signaling molecules. A plausible program for gastric cancer prevention involves intake of a balanced diet containing fruits and vegetables, improved sanitationand hygiene, screening and treatment of H. pylori infection, and follow-up of precancerous lesions. The fact that diet plays an important role in the etiology of gastric cancer offers scope for nutritional chemoprevention. Animal models have been extensively used to analyze the stepwise evolution of gastric carcinogenesis and to test dietary chemopreventive agents. Development of multitargeted preventive and therapeutic strategies for gastric cancer is a major challenge for the future. | Siddavaram Nagini | 2012 | World Journal of Gastrointestinal Oncology2012,4,7: | 87 |
| 2 | Recent advances in gastric cancer early diagnosis显示文摘Gastric cancer(GC) remains an important cause of cancer death worldwide with a high mortality rate due to the fact that the majority of GC cases are diagnosed at an advanced stage when the prognosis is poor and the treatment options are limited. Unfortunately, the existing circulating biomarkers for GC diagnosis and prognosis display low sensitivity and specificity and the GC diagnosis is based only on the invasive procedures such as upper digestive endoscopy. There is a huge need for less invasive or non-invasive tests but also highly specific biomarkers in case of GC. Body fluids such as peripheral blood, urine or saliva,stomach wash/gastric juice could be a source of specific biomarkers, providing important data for screening and diagnosis in GC. This review summarized the recently discovered circulating molecules such as microRNAs, long non-coding RNAs, circular RNAs, which hold the promise to develop new strategies for early diagnosis of GC. | Laura Necula Lilia Matei Denisa Dragu Ana I Neagu Cristina Mambet Saviana Nedeianu Coralia Bleotu Carmen C Diaconu Mihaela Chivu-Economescu | 2019 | World Journal of Gastroenterology2019,25,17: | 70 |
| 3 | Invasive mechanism and control strategy of Ageratina adenophora (Sprengel)显示文摘In order to ascertain the invasive mechanism and control strategy of the invasive Crofton weed, Ageratina adenophora, its ecological adaptability and population differentiation,the formation of single dominant population, displacement of native plants and sustainable management strategies were investigated. The present results helped to clarify and explain such issues as the adaptability post invasion,interaction and competition between inter-and intra-species and community resistance, thereby providing important references to researches on other invasive alien species. | WAN FangHao1, LIU WanXue1, GUO JianYing1, QIANG Sheng2, LI BaoPing2, WANG JinJun3, YANG GuoQing1, NIU HongBang1, GUI FuRong1, HUANG WenKun1, JIANG ZhiLin1 & WANG WenQi3 1State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China 2College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China 3Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, China | 2010 | Science China(Life Sciences)2010,53,11: | 42 |
| 4 | Distant hybridization leads to different ploidy fishes显示文摘Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2n=100, abbreviated as RCC) (♀)×common carp (Cyprinus carpio L.) (2n=100, abbreviated as CC) (♂), and RCC (2n=100) (♀)×blunt snout bream (Megalobrama amblycephala) (2n=48, abbreviated as BSB) (♂) are described. In the distant hybridization of RCC (♀)×CC (♂), bisexual fertile F3–F18 allotetraploid hybrids (4n=200, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2n=100). In another distant hybridization of RCC (♀)×BSB (♂), different ploidy fishes were obtained, including diploid bisexual fertile natural gynogenetic fish (2n=100), sterile triploid hybrids (3n=124), and bisexual fertile tetraploid hybrids (4n=148). Furthermore, two kinds of pentaploid hybrids (5n=172 and 5n=198) were formed. The biological characteristics and the mechanisms of formation of the different ploidy fish were compared and discussed at the cellular and molecular level. The results indicated distant hybridization or the combination of this method with gynogenesis or androgenesis affects the formation of different ploidy fish with genetic variation. | LIU ShaoJun Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha 410081, China | 2010 | Science China(Life Sciences)2010,53,4: | 39 |
| 5 | The relation between HLA-DQA1 genes and genetic susceptibility to duodenal ulcer in Wuhan Hans显示文摘AIM To study the genetic susceptibility of HLA-DQA1 alleles to duodenal ulcer in Wuhan Hans.METHODS Seventy patients with duodenalulcer and fifty healthy controls were examinedfor HLA-DQA1 genotypes.HLA-DQA1 typing wascarried out by digesting the locus specificpolymerase chain reaction amplified productswith alleles specific restriction enzymes(PCR-RFLP),i.e.,Apal Ⅰ,Bsaj Ⅰ,Hph Ⅰ,Fok Ⅰ,Mbo Ⅱ and Mnl Ⅰ.RESULTS The allele frequencies of DQA1 * 0301and DQA1 * 0102 in patients with duodenal ulcerwere significantly higher and lower respectivelythan those in healthy controls(0.40 vs 0.20,P = 0.003,mcorret = 0.024)and(0.05 vs 0.14,P = 0.012,but Pcorret>0.05),respectively.CONCLUSION DQA1 * 0301 is a susceptiblegene for duodenal ulcer in Wuhan Hans,andthere are immunogenetic differences in HLA-DQA1 locus between duodenal ulcer patients andhealthy controls. | Du YP Deng CS Lu DY Huang MF Guo SF Hou W | 2000 | World Journal of Gastroenterology2000,6,1: | 37 |
| 6 | Crop Phenomics and High-Throughput Phenotyping:Past Decades,Current Challenges,and Future Perspectives显示文摘Since whole-genome sequencing of many crops has been achieved,crop functional genomics studies have stepped into the big-data and high-throughput era.However,acquisition of large-scale phenotypic data has become one of the major bottlenecks hindering crop breeding and functional genomics studies.Nevertheless,recent technological advances provide us potential solutions to relieve this bottleneck and to explore advanced methods for large-scale phenotyping data acquisition and processing in the coming years.In this article,we review the major progress on high-throughput phenotyping in controlled environments and field conditions as well as its use for post-harvest yield and quality assessment in the past decades.We then discuss the latest multi-omics research combining high-throughput phenotyping with genetic studies.Finally,we propose some conceptual challenges and provide our perspectives on how to bridge the phenotype-genotype gap.It is no doubt that accurate high-throughput phenotyping will accelerate plant genetic improvements and promote the next green revolution in crop breeding. | Wanneng Yang Hui Feng Xuehai Zhang Jian Zhang John H.Doonan William David Batchelor Lizhong Xiong Jianbing Yan | 2020 | Molecular Plant2020,13,2: | 38 |
| 7 | Dissection of genetic overlap of salt tolerance QTLs at the seedling and tillering stages using backcross introgression lines in rice显示文摘QTLs for salt-tolerance(ST)related traits at the seedling and tillering stages were identified using 99 BC2F8 introgression lines(IL)derived from a cross between IR64(indica)as a recurrent parent and Binam(japonica)from Iran as the donor parent.Thirteen QTLs affecting survival days of seedlings(SDS), score of salt toxicity of leaves(SST),shoot K + concentration(SKC)and shoot Na + concentration(SNC) at the seedling stage and 22 QTLs underlying fresh weight of shoots(FW),tiller number per plant(TN) and plant height(PH)at the tillering stage were identified.Most QTLs detected at the tillering stage showed obvious differential expression to salt stress and were classified into three types based on their differential behaviors.Type I included 11 QTLs which were expressed only under the non-stress condition.Type II included five QTLs expressed in the control and the salt stress conditions,and three of them(QPh5,QPh8 and QTn9)had similar quantity and the same direction of gene effect,suggesting their expression was less influenced by salt stress.Type III included six QTLs which were detectable only under salt stress,suggesting that these QTLs were apparently induced by the stress.Thirteen QTLs affecting trait difference or trait stability of ILs between the stress and non-stress conditions were identified and the Binam alleles at all loci except QPh4,QTn2 and QFw2a decreased trait difference.The three QTLs less influenced by the stress and 13 QTLs affecting trait stability were considered as ST QTLs which contributed to ST.Comparing the distribution of QTLs detected at the seedling and tillering stages,most(69%)of them were genetically independent.Only four were the same or adjacent regions on chromosomes 1,2,8 and 11 harboring ST QTLs detected at the two stages,suggesting that partial genetic overlap of ST across the two stages occurs.It is likely,therefore,to develop ST rice variety for both stages by pyramiding of ST QTLs of different stages or selection against the overlapping QTLs between the two stages via marker-assisted selection(MAS). | ZANG JinPing 1 ,SUN Yong 1 ,WANG Yun 1 ,YANG Jing 1 ,LI Fang 1 ,ZHOU YongLi 1 ,ZHU LingHua 1 , Reys JESSICA2,Fotokian MOHAMMADHOSEIN 2,XU JianLong 1&LI ZhiKang 1,2 1Institute of Crop Sciences/National Key Facility for Crop Gene Resources&Genetic Improvement,Chinese Academy of Agricul- tural Sciences,Beijing 100081,China 2International Rice Research Institute,DAPO Box 7777,Metro Manila,Philippines | 2008 | Science China(Life Sciences)2008,51,7: | 32 |
| 8 | Invasive mechanism and management strategy of Bemisia tabaci(Gennadius) biotype B:Progress report of 973 Program on invasive alien species in China显示文摘Bemisia tabaci(Gennadius) biotype B,called a 'superbug',is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based on our 5-year studies,are presented.Six B.tabaci biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in China.Biotype B dominates the other biotypes in many regions of the country.Genetic diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal application.The activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to insecticides.The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants.Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes.The indigenous B.tabaci biotypes were displaced by the biotype B within 225 d.The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes.B.tabaci biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse conditions.Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T.vaporariorum.Greater ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with T.vaporariorum.Native predatory natural enemies possess greater ability to suppress B.tabaci under field conditions.The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids.The present results provide useful information in explaining the mechanisms of genetic diversity,evolution and molecular eco-adaptation of biotype B.Furthermore,it provides a base for sustainable management of B.tabaci using biological and ecological measures. | WAN FangHao1,ZHANG GuiFen1,LIU ShuSheng2,LUO Chen3,CHU Dong4,ZHANG YouJun4,ZANG LianSheng2,JIU Min2,Lü ZhiChuang1,CUI XuHong1,ZHANG LiPing4,ZHANG Fan3,ZHANG QingWen5,LIU WanXue1,LIANG Pei5,LEI ZhongRen1 & ZHANG YongJun1 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Acadeny of Agriculture Sciences,Beijing 100094,China 2 Institute of Applied Entomology,Zhejiang University,Hangzhou 310029,China 3 Institute of Plant and Environment Protection,Beijing Academy of Agricultural and Forestry Sciences,Beijing 100089,China 4 Institute of Vegetables and Flowers,Chinese Acadeny of Agricullare Sciences,Beijing 100081,China 5 Department of Entomology,China Agriculture University,Beijing 100094,China | 2009 | Science China(Life Sciences)2009,52,1: | 30 |
| 9 | Genetic and epigenetic biomarkers for diagnosis, prognosis and treatment of colorectal cancer显示文摘Colorectal cancer(CRC)is one of the most common cancer worldwide and results from the accumulation of mutations and epimutations in colonic mucosa cells ultimately leading to cell proliferation and metastasis.Unfortunately,CRC prognosis is still poor and the search of novel diagnostic and prognostic biomarkers is highly desired to prevent CRC-related deaths.The present article aims to summarize the most recent findings concerning the use of either genetic or epigenetic(mainly related to DNA methylation)biomarkers for CRC diagnosis,prognosis,and response to treatment.Recent large-scale DNA methylation studies suggest that CRC can be divided into several subtypes according to the frequency of DNA methylation and those of mutations in key CRC genes,and that this is reflected by different prognostic outcomes.Increasing evidence suggests that the analysis of DNA methylation in blood or fecal specimens could represent a valuable non-invasive diagnostic tool for CRC.Moreover,a broad spectrum of studies indicates that the inter-individual response to chemotherapeutic treatments depends on both epigenetic modifications and genetic mutations occurring in colorectal cancer cells,thereby opening the way for a personalized medicine.Overall,combining genetic and epigenetic data might represent the most promising tool for a proper diagnostic,prognostic and therapeutic approach. | Fabio Coppedè Angela Lopomo Roberto Spisni Lucia Migliore | 2014 | World Journal of Gastroenterology2014,20,4: | 29 |
| 10 | Parental transmission of type 2 diabetes mellitus in a highly endogamous population显示文摘AIM: To determine the parental transmission of diabetes mellitus (DM) and evaluate its influence on the clinical characteristics. METHODS: This was a cross sectional study. The survey was carried out in urban and semi-urban primary health care centers. Of the 2400 registered with diagnosed diabetes, 1980 agreed and gave their consent to take part in this study, thus giving a response rate of 82.5%. Face to face interviews were conducted using a structured questionnaire followed by laboratory tests. DM was defined according to the World Health Organization expert group. A trained nurse performedphysical examinations and measurements. RESULTS: Of the study population, 72.9% reported a family history of DM. Family history of DM was significantly higher in females (54.2%; P = 0.04) and in the age group below 30 years (24%; P < 0.001). The prevalence of diabetes was higher among patients with a diabetic mother (25.4% vs 22.1%) and maternal aunts/uncles (31.2% vs 22.2%) compared to patients with a diabetic father and paternal aunts/ uncles. Family history of DM was higher in patients of consanguineous parents (38.5%) than those of non-consanguineous parents (30.2%). The development of type 2 diabetes mellitus (T2DM) complications was higher in patients with either a paternal or maternal history of DM than in those without. No significant difference was observed in the metabolic characteristics of patients with/without family history of DM except for hypertension. Complications were higher in diabetic patients with a family history of DM. CONCLUSION: The present study found a significant maternal effect in transmission of T2DM. Family history is associated with the increased incidence of diabetes. | Abdulbari Bener Mohammad T Yousafzai Abdulla OAA Al-Hamaq Abdul-Ghani Mohammad Ralph A DeFronzo | 2013 | World Journal of Diabetes2013,4,2: | 28 |
| 11 | Venous thrombosis and prothrombotic factors in inflammatory bowel disease显示文摘Patients with inflammatory bowel disease(IBD)may have an increased risk of venous thrombosis(VTE).PubMed,ISI Web of Knowledge and Scopus were searched to identify studies investigating the risk of VTE and the prevalence of acquired and genetic VTE risk factors and prothrombotic abnormalities in IBD.Overall,IBD patients have a two-to fourfold increased risk of VTE compared with healthy controls,with an overall incidence rate of 1%-8%.The majority of studies did not show significant differences in the risk of VTE between Crohn’s disease and ulcerative colitis.Several acquired factors are responsible for the increased risk of VTEin IBD:inflammatory activity,hospitalisation,surgery,pregnancy,disease phenotype(e.g.,fistulising disease,colonic involvement and extensive involvement)and drug therapy(mainly steroids).There is also convincing evidence from basic science and from clinical and epidemiological studies that IBD is associated with several prothrombotic abnormalities,including initiation of the coagulation system,downregulation of natural anticoagulant mechanisms,impairment of fibrinolysis,increased platelet count and reactivity and dysfunction of the endothelium.Classical genetic alterations are not generally found more often in IBD patients than in nonIBD patients,suggesting that genetics does not explain the greater risk of VTE in these patients.IBD VTE may have clinical specificities,namely an earlier first episode of VTE in life,high recurrence rate,decreased efficacy of some drugs in preventing further episodes and poor prognosis.Clinicians should be aware of these risks,and adequate prophylactic actions should be taken in patients who have disease activity,are hospitalised,are submitted to surgery or are undergoing treatment. | Fernando Magro Jo?o-Bruno Soares Dália Fernandes | 2014 | World Journal of Gastroenterology2014,20,17: | 27 |
| 12 | Genetic analysis of 'all-fish' growth hormone gene transferred carp (Cyprinus carpio L.) and its F_1 generation显示文摘Recornbinant 'all-fish' growth hormone gene (GH) was microinjected into the fertilized eggs of carp. A comparison between the growth traits of transgenics and non-transgenics was carried out, and the transgenic individuals with significant 'fast-growing' effect were successfully gained. A comparison on the reproductivities was also given out between the transgenics and their non-transgenic siblings, and showed that the reproductive capacity of transgenics was substantially equivalent to those of the non-transgenics. On the other hand, the genetic separation and the characteristic distribution of the FI generation were genetically analyzed, which gave solid evidence for the hypothesis that 2-3 chromosomes are integrated with trans-gene. In addition, the distinct biological effects for multi-site-integrated transgenes were further discussed. The present study opens a door for the breeding of 'fast-growing' transgenic fish. | WANG Yaping, HU Wei, WU Gang,SUN Yonghua, CHEN Shangping, ZHANG Fuying,ZHU Zuoyan, FENG Jianxin & ZHANG Xirui1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China 2. Henan Institute of Aquaculture, Zhengzhou 450044, China | 2001 | Chinese Science Bulletin2001,46,14: | 23 |
| 13 | The distribution rule and seepage effect of the fractures in the ultra-low permeability sandstone reservoir in east Gansu Province,Ordos Basin显示文摘To study the impact of the fractures on development in the ultra-low permeability sandstone reservoir of the Yangchang Formation of the Upper Triassic in the Ordos Basin,data on outcrops,cores,slices,well logging and experiments are utilized to analyze the cause of the formation of the fractures,their distribution rules and the control factors and discuss the seepage flow effect of the fractures. In the studied area developed chiefly high-angle tectonic fractures and horizontal bedding fractures,inter-granular fractures and grain boundary fractures as well. Grain boundary fractures and intragranular fractures serve as vital channels linking intragranular pores and intergranular solution pores in the reservoir matrix,thus providing a good connectivity between the pores in the ultra-low perme-ability sandstone reservoir. The formation of fractures and their distribution are influenced by such external and internal factors as the palaeo-tectonic stress field,the reservoir lithological character,the thickness of the rock layer and the anisotropy of a layer. The present-day stress field influences the preservative state of fractures and their seepage flow effect. Under the tec-tonic effect of both the Yanshan and Himalayan periods,in this region four sets of fractures are distributed,respectively assuming the NE-SW,NW-SE,nearly E-W and nearly S-N orientations,but,due to the effect of the rock anisotropy of the rock formation,in some part of it two groups of nearly orthogonal fractures are chiefly distributed. Under the effect of the present-day stress field,the fractures that assume the NE-SW direction have a good connectivity,big apertures,a high permeability and a minimum starting pressure,all of which are main advantages of the seepage fractures in this region. With the development of oilfields,the permeability of the fractures of dif-ferent directions will have a dynamic change. | ZENG LianBo1,GAO ChunYu2,QI JiaFu1,WANG YongKang2,LI Liang2 & QU XueFeng2 1 State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China 2 Changqing Oilfield Branch,PetroChina,Xi’an 163517,China | 2008 | Science China Earth Sciences2008,51,S2: | 22 |
| 14 | 中国西北内陆干旱区大叶白麻野生居群遗传多样性研究(英文)显示文摘[Objective] Study on the genetic diversity in wild populations of Poacynum hendersonii.[Method] Random amplified polymorphic DNA(RAPD)technique was employed to analyze the genetic diversity in five wild populations of P.hendersonii sampled from Xinjiang,Gansu and Qinghai provinces.[Result] Totally 165 clear and repeatable bands were generated in RAPD reaction by using 20 primers screened from 80 primers,of which 110 were polymorphic,accounting for 66.67%.At species level,Nei's gene diversity index(H),Shannon's information index(I)and genetic differentiation coefficient(Gst)were 0.220 5,0.304 7 and 0.908 2,respectively.P.hendersonii germplasm resources share a high level of genetic diversity,and genetic differentiation mainly exists among the populations.Results from genetic distances and cluster analysis showed that relationships among P.hendersonii populations were to some extent related with their geographical and climatic characters.[Conclusion] This study suggests that the conservation of P.hendersonii should focus on the protection of many populations,particularly the Qinghai population. | 赵金凤 张卫明 彭雪梅 唐泽紫 顾龚平 陆长梅 | 2008 | Agricultural Science & Technology2008,9,4: | 21 |
| 15 | Genetic diversity in Chinese modern wheat varieties revealed by microsatellite markers显示文摘Genetic diversity of 1680 modern varieties in Chinese candidate core collections was analyzed at 78 SSR loci by fluorescence detection system. A total of 1336 alleles were detected, of which 1253 alleles could be annotated into 71 loci. For these 71 loci, the alleles ranged from 4 to 44 with an average of 17.6, and the PIC values changed from 0.19 to 0.89 with an average of 0.69. (1) In the three genomes of wheat, the average genetic richness was B>A>D, and the genetic diversity indexes were B>D>A. (2) Among the seven homoeologous groups, the average genetic richness was 2=7>3>4>6>5>1, and the genetic diversity indexes were 7>3>2>4>6>5>1. As a whole, group 7 possessed the highest genetic diversity, while groups 1 and 5 were the lowest. (3) In the 21 wheat chromosomes, 7A, 3B and 2D possessed much higher genetic diversity, while 2A, 1B, 4D, 5D and 1D were the lowest. (4) The highest average genetic diversity index existed in varieties bred in the 1950s, and then it declined continually. However, the change tendency of genetic diversity among decades was not greatly sharp. This was further illustrated by changes of the average genetic distance between varieties. In the 1950s it was the largest (0.731). Since the 1960s, it has decreased gradually (0.711, 0.706, 0.696, 0.695). The genetic base of modern varieties is becoming narrower and narrower. This should be given enough attention by breeders and policy makers. | HAO Chenyang, WANG Lanfen, ZHANG Xueyong, YOU Guangxia, DONG Yushen, JIA Jizeng, LIU Xu, SHANG Xunwu, LIU Sancai & CAO Yongsheng Key Laboratory of Crop Germplasm & Biotechnology, MOA, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China Agronomy College, Gansu Agricultural University, Lanzhou 730070, China | 2006 | Science China(Life Sciences)2006,49,3: | 19 |
| 16 | Construction of infectious cDNA clones of PRRSV:Separation of coding regions for nonstructural and structural proteins显示文摘Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), the causative agent of the ongoing 'porcine high fever syndrome' in China, is capable of genetic and antigenic mutations at high fre- quency. How to design vaccine rationally to keep up with the ever-changing prevalent PRRSV variant is of great interest. We developed an infectious cDNA clone of an attenuated strain of Type II PRRSV, and further manipulated the infectious cDNA clone by inserting polylinker between ORF1 and ORF2, en- coding for nonstructural- or structural-protein, respectively. The cDNA was generated from the cell-attenuated virus strain, APRRS, via RT-PCR, and followed by nucleotide sequencing and molecular cloning. The full-length of the APRRS genomic RNA was determined as 15521 nucleotides in length excluding poly(A) tail, which has a 99.7% nucleotide identity with that of PRRSV Nsp strain, also a vac- cine strain. Based on the nucleotide sequencing results, the full-length cDNA clone was assembled in pBlueScript vector, under the control of T7 promoter at the immediate 5′ terminus of genome. To dis- cern the rescued viruses from that of parental virus, a Mlu I restriction site was engineered into ORF5 coding region. Upon transfection of the in vitro transcripts of both the original and Mlu I-tagged cDNAs into MA-104 cells, typical PRRSV cytopathic effects were observed. The rescued viruses from the full-length cDNA clones displayed the same virological and molecular properties. Subsequently, PCR-based mutagenesis was conducted to separate the coding regions between PRRSV nonstructural genes, ORF1, and structural proteins, ORF2-ORF7. The synthetic RNA of such mutant clone, pCSA, was infectious and the rescued virus shared similar properties with that of the parental virus. This study provided a valuable tool for development of chimeric PRRSV as vaccine candidate offering cross-protection to various genetically diversified PRRSV strains, and a platform for further develop- ment of PRRSV as a gene expression vector for recombinant vaccines against other significant swine diseases. | YUAN ShiShan & WEI ZuZhang Department of Animal Infectious Diseases, Key Laboratory of Animal Parasitology Chinese Ministry of Agriculture, Shanghai Vet- erinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200232, China | 2008 | Science China(Life Sciences)2008,51,3: | 19 |
| 17 | Molecular mapping of Verticillium wilt resistance QTL clustered on chromosomes D7 and D9 in upland cotton显示文摘Verticillium wilt is a destructive disease with international consequences for cotton production. Breeding broad-spectrum resistant cultivars is considered to be one of the most effective means for reducing crop losses. A resistant cotton cultivar,60182,was crossed with a susceptible cultivar,Jun-mian 1,to identify markers for Verticillium resistance genes and validate the mode of its inheritance. Genetic segregation analysis for Verticillium wilt resistance was evaluated based upon infected leaf percentage in the seedling stage using major gene-polygene mixed inheritance models and joint analysis of P1,P2,F1,B1,B2 and F2 populations obtained from the cultivar cross. We found that resistance of upland cotton cultivar 60182 to isolates BP2,VD8 and T9,and their isoconcentration mixture was controlled by two major genes with additive-dominance-epistatic effects,and the inheritance of the major gene was dominant. Furthermore,a genetic linkage map was constructed using F2 segregating population and resistance phenotypic data were obtained using F2:3 families inoculated with different isolates and detected in different developmental stages. The genetic linkage map with 139 loci was comprised of 31 linkage groups covering 1165 cM,with an average distance of 8.38 cM between two markers,or 25.89% of the cotton genome length. From 60182,we found 4 QTL on chromosome D7 and 4 QTL on D9 for BP2,5 QTL on D7 and 9 QTL on D9 for VD8,4 QTL on D7 and 5 QTL on D9 for T9 and 3 QTL on D7 and 7 QTL on D7 for mixed pathogens. The QTL mapping results revealed that QTL clusters with high contribution rates were screened simultaneously on chromosomes D9 and D7 by multiple interval mapping (CIM),whether from resistance phenotypic data from different developmental stages or for different isolates. The result is consistent with the genetic model of two major genes in 60182 and suggests broad-spectrum resistance to both defoliating isolates of V. dahliae and nondefoliating isolates. The markers associated with resistance QTL may facilitate the use of Verticillium wilt resistance genes in improving breeding programs for cotton. | JIANG Feng,ZHAO Jun,ZHOU Lei,GUO WangZhen & ZHANG TianZhen National Key Laboratory of Crop Genetics & Germplasm Enhancement,Cotton Research Institute,Nanjing Agricultural University,Nanjing 210095,China | 2009 | Science China(Life Sciences)2009,52,9: | 18 |
| 18 | RAPD analysis of wild stock of penaeid shrimp (Penaeus chinensis )in Chinese coastal waters of the Huanghai Sea and coastal waters of the Bohai Sea显示文摘Genetic diversity of 32 individuals of P. chinensis in the Chinese coastal waters of the Huanghai and Bobal Seas was detected by RAPD technique. Twenty decamer primers of OPI were used for DNA amplification for each individual. The results showed that: Seventeen primers obtained reproducible fingerprints, and the bands were clear. Thirty--nine of 106 loci detected were polymorphic, amounting to 36. 8 %. Mean genetic distance was 0. 094 1 0. 020 6; 68 markers (63. 2 % of the total) showed stable homogeneity in all of the 32 individuals. | Liu Ping Kong Jie Shi Tuo Zhuang Zhimeng Deng Jingyao (l. Huanghai Sea Fisheries Research institute , Chinese Academy of Fishery Sciences, Qingdao 266071, China) | 2000 | Acta Oceanologica Sinica2000,19,1: | 18 |
| 19 | Genetic Diversity and Structure of Tunisian Local Pear Germplasm as Revealed by SSR Markers显示文摘Growing pear has a long tradition in Tunisia, and numerous local cultivars possessing an excellent adaptability and resilience potential to climatic variation are present. This large adaptability is associated with an important genetic diversity, which is threatened to erosion.Appropriate measures have to be taken in order to properly evaluate and conserve this local material. Microsatellite markers were used to assess the level of genetic diversity among Tunisian pear germplasm, and compare it with some European varieties and wild pear species. 61 pear accessions representing eight groups(six groups from Tunisia, one from Northern Europe and another group composed of wild pear) have been genotyped using SSR markers derived from apple and pear. The pear accessions showed a significant polymorphism and 95 polymorphic alleles were found. The number of alleles per locus varied from 5 for CH04e03 locus to 14 for CH01d09 locus with an average of 9.4 alleles per locus.Moreover, the mean gene diversity(H_e) per locus ranged from 0.192 to 0.752. Genetic distance values and cluster analyses revealed high genetic similarities among the Tunisian groups. Factorial correspondence analysis(FCA) categorized the accessions into three independent groups where Tunisian local accessions agglomerated together distantly from European and wild pear accessions. Additionally, UPGMA dendrogram grouped accessions into two clusters, confirmed thereafter by the Bayesian model-based Structure analysis. The results showed 16 putative triploid accessions found in the local germplasm. This study provides valuable information to develop strategies of local pear conservation and use. | Rim Ouni Anna Zborowska Jasna Sehic Sarra Choulak JInaki Hormaza Larisa Garkava-Gustavsson Messaoud Mars | 2020 | Horticultural Plant Journal2020,6,2: | 18 |
| 20 | Recent developments in the pathophysiology of irritable bowel syndrome显示文摘Irritable bowel syndrome(IBS) is a common gastrointestinal disorder, the pathophysiology of which is not completely known, although it has been shown that genetic/social learning factors, diet, intestinal microbiota, intestinal low-grade inflammation, and abnormal gastrointestinal endocrine cells play a major role. Studies of familial aggregation and on twins have confirmed the heritability of IBS. However, the proposed IBS risk genes are thus far nonvalidated hits rather than true predisposing factors. There is no convincing evidence that IBS patients suffer from food allergy/intolerance, with the effect exerted by diet seemingly caused by intake of poorly absorbed carbohydrates and fiber. Obesity is a possible comorbidity of IBS. Differences in the microbiota between IBS patients and healthy controls have been reported, but the association between IBS symptoms and specific bacterial species is uncertain. Low-grade inflammation appears to play a role in the pathophysiology of a major subset of IBS, namely postinfectious IBS. The density of intestinal endocrine cells is reduced in patients with IBS, possibly as a result of genetic factors, diet, intestinal microbiota, and low-grade inflammation interfering with the regulatory signals controlling the intestinal stem-cell clonogenic and differentiation activities. Furthermore, there is speculation that this decreased number of endocrine cells is responsible for the visceral hypersensitivity, disturbed gastrointestinal motility, and abnormal gut secretion seen in IBS patients. | Magdy El-Salhy | 2015 | World Journal of Gastroenterology2015,21,25: | 17 |