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1Source mechanism of strong aftershocks (M_s≥5.6) of the 2008/05/12 Wenchuan earthquake and the implication for seismotectonics显示文摘Dozens of >M5, hundreds of >M4, and much more >M3 aftershocks occurred after the 2008/05/12 Wenchuan earthquake, which were well recorded by permanent and portable seismic stations. After relocated with P arrival, the >M3 aftershocks show two trends of distribution, with most of the aftershocks located along the north-east strike consistent with Longmenshan fault system, yet there is a north-west trend around the epicenter. It seems that substantially more aftershocks occur in regions with crystalline bedrocks. Then we collected waveform data from National Digital Seismograph Network and regional seismograph network of China, and employed 'Cut and Paste' method to obtain focal mechanisms and depths of the big aftershocks (M≥5.6). While most of those aftershocks show thrust mechanism, there are some strike slip earthquakes in the northern-most end of the rupture. Focal mechanisms show that the events located on the southern part of central Beichuan-Yingxiu Fault (BY) are mainly thrust earthquakes, which is consistent with initial mechanism of the main shock rupture. In the north part the aftershocks along the BY are also dominated by thrust slip, which is quite different from the right slip rupture of the main shock. Around Qingchuan-Pingwu Fault, the focal mechanisms are dominated by right-slip rupture with large depths (~18 km). So we suspected that in the north part the main shock might rupture on two faults: Beichuan Fault and Qingchuan-Pingwu Fault. The complex pattern of aftershock mechanisms argues for presence of a complicated fault system in the Longmenshan area.ZHENG Yong1,2,MA HongSheng3,Lü Jian4,NI SiDao5,LI YingChun6 & WEI ShengJi2 1 Institute of Geodesy and Geophysics,Chinese Academy of Sciences,Wuhan 430077,China 2 Institute of Geophysics,Chinese Earthquake Administration,Beijing 100086,China 3 Institute of Earthquake Science,Chinese Earthquake Administration,Beijing 100086,China 4 Earthquake Administration of Jiangxi Province,Nanchang 330039,China 5 School of Earth and Space Science,University of Science and Technology of China,Hefei 230026,China 6 Earthquake Administration of Jiangsu Province,Nanjing 210014,China 2009Science China Earth Sciences2009,52,6:100
2我国面临快速增长的终末期肾病治疗负担显示文摘目的报告2008年我国终末期肾脏病维持性透析患病率和发病率,并估计未来维持性透析的趋势。方法中国医院协会血液净化中心管理分会制定调查表,以透析登记软件及纸质版形式下发至各省、自治区和直辖市的血液净化中心管理分会/血液净化质量控制中心,收集各透析室的数据,包括2007年底和2008年底患者数量,以及2008年新进入透析的患者数量;患者的性别和年龄构成;导致终末期肾脏病(ESRD)的原因以及所有死亡患者的原因。分析2007和2008年底ESRD的点患病率、2008年ESRD发病率、ESRD病因以及死亡原因构成。结果全国31个省、自治区和直辖市中,27个应答。2007年底,共报告65074例ESRD患者,点患病率为每百万人口51.7;2008年底患者数增至102863例,点患病率为每百万人口79.1,患病率增长52.9%。2008年ESRD新患者数为45423例,发病率每百万人口36.1。ESRD的病因依次为肾小球肾炎(45%)、糖尿病(19%)、高血压(13%)、多囊肾病(2%)和其他或未知(20%)。ESRD主要死亡原因是心血管疾病(31%)、中风(20.3%)、感染(19.9%)和其他(28.8%)。结论虽然我国ESRD的患病率显著低于其他亚洲国家和地区,但发病率极高,未来几年患病率也将快速增加,从而增加我国ESRD的治疗负担。Li Zuo M.D.1 and Mei Wang M.D.2 for Chinese Society of Blood Purification Institute of Nephrology,Peking University First 1 Hospital Institute of Nephrology,Peking University People’s Hospital 2 2010中国血液净化2010,,1:145
3Apoptosis and its relationship with cell proliferation,p53,Waf1p21,bcl-2 and c-mycin esophageal carcinogenesis studied with a high-risk population in northern China显示文摘Apoptosisanditsrelationshipwithcelproliferation,p53,Waf1p21,bcl2andcmycinesophagealcarcinogenesisstudiedwithahighriskpopul...WANG LiDong1, ZHOU Qi1, WEI JunPing1, YANG WanCai1, ZHAO Xin1, WANG LiXia1, ZOU Jian Xiang1, GAO ShanShan1, LI YongXin1 and YANG C.S.2Keywords esophageal neoplasms apoptosis precancerous lesions Waf1 p21 gene p53 1998World Journal of Gastroenterology1998,4,4:295
4Magnetostratigraphy of the late Cenozoic Laojunmiao anticline in the northern Qilian Mountains and its implications for the northern Tibetan Plateau uplift显示文摘Cenozoic sediments in the foreland basin--Jiuquan Basin in west Hexi Corridor recorded tectonic uplift information of the Qilian Mountains. High resolution paleomagnetic dating of the Laojunmiao (LJM) section across the central LJM anticline in the southern Jiuquan Basin reveals ages of the Getanggou Member, Niugetao Member in the Shulehe Formation, the Yumen Conglomerate, Jiuquan Conglomerate and Gobi Formation at >13-8.3 Ma, 8.3-4.9 Ma, 3.66-0.93 Ma, 0.84-0.14 Ma and 0.14-0 Ma, respectively. Sedimentary evolution study suggests that the Qilian Mountains should begin to rise gradually since ~8-6.6 Ma, accompanied by sedimentary environments changing from lacustrine mudstones-sandstones to alluvial conglomerates. Rapid uplift of the Qilian Mountains began at ~3.66 Ma, followed by a series of stepwise or intermittent intensive uplifts at about <1.8-1.23 Ma, 0.93-0.84 Ma and 0.14 Ma, which finally resulted in the present high Qilian Mountains.FANG Xiaomin1,2, ZHAO Zhijun3,2, LI Jijun2, YAN Maodu2, PAN Baotian2, SONG Chunhui2 & DAI Shuang2 1. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2. Key Laboratory of Western China’s Environmental Systems, Ministry of Education & College of Resources and Environment, Lanzhou University, Lanzhou 730000, China 3. College of Geography, Nanjing Normal University, Nanjing 210097, China 2005Science China Earth Sciences2005,48,7:61
5Alterations in metastatic properties of hepatocellular carcinoma cell following H-ras oncogene transfection显示文摘AIM To demonstrate the relationship betweenH-ras oncogene and hepatocellular carcinoma(HCC) metastasis.METHODS Activated H-ras oncogene wastransfected into SMMC 7721, a cell line derivedfrom human HCC, by calcium phosphatetransfection method. Some metastasis-relatedparameters were detected in vitro, includingadhesion assay, migration assay, expression ofcollagenase ⅣV (c ⅣV ase) and epidermal growthfactor receptor (EGFR).RESULTS The abilities of H-ras-transfected cellclones in adhesion to laminin (LN) or fibronectin(FN), migration, c Ⅳ ase secretion increasedmarkedly, and the expression of EGFR elevatedmoderately. More importantly, these alterationswere consistent positively with the expressionof p21, the protein product of H-ras oncogene.CONCLUSION H-ras oncogene could inducethe metastatic phenotype of HCC cell in vitro toraise its metastatic potential.Qing Wang~1 Zhi Ying Lin~2 Xiao Li Feng~3 ~1Department of Microbiology,Medical Center of Fudan University.the former Shanghai Medical University,Shanghai 200032,China ~2Liver Cancer Institute,Zhongshan Hospital,Shanghai 200032,China ~3Shanghai Institute of Biochemistry,Academy Sinica,Shanghai 200031,ChinaQing Wang earned master degree from Shanghai Medical University in 1996,now a senior lecturer of microbiology,specialized in the role of oncogcncs on tumor metastasis,having 8 papers published. 2001World Journal of Gastroenterology2001,7,3:48
6The deformation pattern and fault rate in the Tianshan Mountains inferred from GPS observations显示文摘Based on GPS measurements conducted from 1992 to 2006, we present the current crustal movement velocity field for approximately 400 sites in the Tianshan Mountains and their adjacent areas, and estimate slip rates on the major faults using a 2-D elastic dislocation model. Our studies show slip rates within the range of 1―4 mm/a on the NW-SE trending strike-slip faults (such as Talas-Fergana fault) in the Tianshan Mountains. We also found the slip rates on the approximately WE-SN trending gently-dipping detachment fault vary from 10―13 mm/a for the southwest Tianshan Mountains to 2―5 mm/a for the eastern Tianshan Mountains, and to 6―12 mm/a for the Kyrgrz Tianshan. The GPS velocity field reveals that the total convergence is not uniformly distributed across the Tianshan Mountains, with 80%―90% of the N-S shortening absorbed along the southern and northern edges, and relatively little deformation accommodated within the interior. This first-order feature of strain pattern is explained best by underthrusting of adjacent blocks beneath the Tianshan Mountains along a basal detachment fault. We found the occurrence of historical M7―8 earthquakes somewhere in the locked ramp that connects the creeping and locking segments of the detachment, thereby resulting in elastic strain concentration and accumulation around it. The elastic strain confined in the upper crustal layer above the detachment ultimately releases through infrequent great earthquakes in the Tianshan Mountains, resulting in considerable folding and faulting at their margins. The Tianshan Mountains propagated outward and rose progressively as a wedge-shaped block.YANG ShaoMin1,2, LI Jie1,3 & WANG Qi2,1 1 Research Center of Space Science and Technology, China University of Geosciences, Wuhan 430074, China 2 Institute of Seismology, China Earthquake Administration, Wuhan 430071, China 3 Earthquake Administration of Xinjiang Uygur Autonomous Region, Urumqi 830011, China 2008Science China Earth Sciences2008,51,8:43
7Changes in the level of serum liver enzymes after laparoscopic surgery显示文摘AIM: The purpose of this study was to investigate the effectof laparoscopic surgery on liver function in humans and thepossible mechanisms behind such effect.METHODS: Blood samples from 286 patients whounderwent laparoscopic cholecystectomy (LC) and 40patients who underwent open cholecystectomy (OC) weretested for liver function by measuring the level of serumalanine aminotrasferase (ALT) and aspartate aminotrasferase(AST) before and after the operations. The same tests werealso applied to 18 laparoscopic colorectal cancer resection(LCR) patients and 23 open colorectal cancer resection (OCR)patients to determine whether CO2 pneumoperitoneum couldalter the serum liver enzymes.RESULTS: The level of serum ALT and AST increasedsignificantly during the first 48 hours post operations in bothLC and LCR patients. However, no significant change of theserum liver enzymes was detected in both OC and OCRpatients. As a result, there was statistically significantdifference in change of both ALT and AST levels betweenLC and OC patients and LCR and OCR patients, respectively.By the 7th day post operation, the level of both enzymesreturned to normal values in LC, OC and OCR patients exceptLCR patients whose enzymes remained at a higher level.CONCLUSION: Transient elevation of hepatic transaminasesoccurred after laparoscopic surgery. The major causativefactor seemed to be the CO2 pneumoperitoneum. In mostof the laparoscopic surgery patients, the transient elevationof serum liver enzymes showed no apparent clinicalimplications. However, if preoperative liver function was verypoor, laparoscopic surgery may not be the best choice forthe treatment of patients with certain abdominal diseases.Min Tan Feng-Feng Xu Jun-Shen Peng Dong-Ming Li Liu-Hua Chen Bao-Jun Lv Zhen-Xian Zhao Chen Huang Chao-Xu Zheng Department of General Surgery, the First Affiliated Hospital of Zhong Shah University, 58 Zhongshan 2 Road Guangzhou 510080, Guangdong Province China 2003World Journal of Gastroenterology2003,9,2:42
8Treatment outcomes for different subgroups of nasopharyngeal carcinoma patients treated with intensity-modulated radiation therapy显示文摘Although many studies have investigated intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC),sample sizes in the reported studies are usually small and different in outcomes in different T and N subgroups are seldom analyzed.Herein,we evaluated the outcomes of NPC patients treated with IMRT and further explored treatment strategy to improve such outcome.We collected clinical data of 865 NPC patients treated with IMRT alone or in combination with chemotherapy,and classified all cases into the following prognostic categories according to different TNM stages:early stage group (T1-2N0-1M0),advanced local disease group (T3-4N0-1M0),advanced nodal disease group (T1-2N2-3M0),and advanced locoregional disease group (T3-4N2-3M0).The 5-year overall survival (OS),local relapse-free survival (LRFS),and distant metastases-free survival (DMFS) were 83.0%,90.4%,and 84.0%,respectively.The early disease group had the lowest treatment failure rate,with a 5-year OS of 95.6%.The advanced local disease group and advanced nodal disease group had similar failure pattern and treatment outcomes as well as similar hazard ratios for death (4.230 and 4.625,respectively).The advanced locoregional disease group had the highest incidence of relapse and death,with a 5-year DMFS and OS of 62.3% and 62.2%,respectively,and a hazard ratio for death of 10.402.Comparing with IMRT alone,IMRT in combination with chemotherapy provided no significant benefit to locoregionally advanced NPC.Our results suggest that the decision of treatment strategy for NPC patients should consider combinations of T and N stages,and that IMRT alone for early stage NPC patients can produce satisfactory results.However,for advanced local,nodal,and locoregional disease groups,a combination of chemotherapy and radiotherapy is recommended.Sheng-Fa Su 1,2,3,Fei Han 1,2,Chong Zhao 1,2,Ying Huang 1,2,Chun-Yan Chen 1,2,Wei-Wei Xiao 1,2,Jia-Xin Li 1,2 and Tai-Xiang Lu 1,2 1 State Key Laboratory of Oncology in South China,Guangzhou,Guangdong 510060,P.R.China 2 Department of Radiation Oncology,Sun Yat-sen University Cancer Center,Guangzhou,Guangdong 510060,P.R.China 3 Department of Oncology,Guiyang Medical College Hospital,Tumor Hospital of Guizhou,Guiyang,Guizhou 550003,P.R.China. 2011Chinese Journal of Cancer2011,30,8:40
9Reduction of the incidence and mortality of rectal cancer bypolypectomy:a prospective cohort study in Haining County显示文摘AIM: To reduce the incidence and morlality of rectal cancerand address the hypothesis that colorectal cancer often arisefrom precursor lesion (s), either adenomas or non-alenomatous polyps, by conducting a population-basedmass screening for colorectal cancer in Haining County,Zhejiang, PRCMETHODS: From 1977 to 1980, physicians screened thepopulation of Haining County using 15 cm rigid endoscopy.Of over 240 000 participants, 4076 of them were diagnoselwith Precursor Iesions, eitler alenomas or non-adenomatous polyps, which were then removedl surgically.All individuals with precursor lesionswere followed up andreexamined by endoscopy every two to five years upto 1998.RESULTS: After the initial screening, 953 metactronousadenomas and 417 non-adenomatous polyps ware detected andremoved from the members of this cohort. Further, 27 cases ofcolorectal cancer were detected and treated. Log-rank tuestsshowed that the survival time among those cancer patients whounderwent mass screening increased significantly comparedtothat of other colorectal cancer patients (P < 0.0001). Accordingto the population-based cancer registry in Haining County,age-adjusted incidence and mortality of rectal cancer decreasedby 41% and 29 % from 1977-1981 to 1992-1996, respectively.Observed cumulative 20-year rectal cancer incidence was 31%lower than the expected in the screened group; the mortalitydue to rectal cancer was 18 % lower thah the expected in thescreened group.CONCLUSION: Mass screening for rectal cancer andprecursor lesions with protocoscopy in the generalpopulation and periodical following-up with routineendoscopy for high-risk patients may decrease both theincidence and mortality of rectal cancer.Shu Zheng Xi-Yong Liu Qi Dong,Cancer Institute,Zhejiang University,88 Jiefang Road,HangZhou 310009,Zhejiang Province,China Ke-feng Ding Lin-Bo Wang Pei-Lin Qiu Su-Zhan Zhang,The 2~(nd)affiliated Hospital,Medical School of Zhejiang University,88 Jiefang Road,HangZhou 310009,Zhejiang Province,China Xin-Feng Ding Yong-Zhou Shen Gao-Fei Shen Oi-Rong Sun Wei-Dong Li,Haining Cancer Institute,Haining 314400,Zhejiang Province,China 2002World Journal of Gastroenterology2002,8,3:37
10Leptin: a multifunctional hormone显示文摘Leptin is the protein product encoded by the obese (ob)gene. It is a circulating hormone produced primarily by the adipose tissue. ob/ob mice with mutations of the gene encoding leptin become morbidly obese, infertile, hyperphagic, hypothermic,and diabetic. Since the cloning of leptin in 1994, our knowledge in body weight regulation and the role played by leptin has increased substantially. We now know that leptin signals through its receptor, OB-R, which is a member of the cytokine receptor superfamily. Leptin serves as an adiposity signal to inform the brain the adipose tissue mass in a negative feedback loop regulating food intake and energy expenditure. Leptin also plays important roles in angiogenesis, immune function, fertility and bone formation. Humans with mutations in the gene encoding leptin are also morbidly obese and respond to leptin treatment,demonstrating that enhancing or inhibiting leptin’s activities in vivo may have potential therapeutic benefits.HUANG Lu, CAI LI(Tel: (214)-648-3340 Fax: (214)-648-9191 E-mail: li03@utsw.swmed.edu)(1 Touchstone Center for Diabetes Research1 Departments of Physiology and,2 Departments of Internal MedicineThe University of Texas Southwestern Medical Center5323 H. 2000Cell Research2000,10,2:35
11The fragment of Paleo-Tethys ophiolite from central Qiangtang, Tibet:Geochemical evidence of meta-basites in Guoganjianian显示文摘N-MORB-type metabasites are discovered in the Guoganjianian area, central Qiangtang, Tibet, which are mainly metagabbro with cumulate structure and metabasalt. The rocks are distributed nearly from west to east unconformably underlying the Wanghuling Group of upper Triassic. On the basis of geo- chemical analysis, we find that the content of SiO2 is 43.03%―53.42%, and TiO2 1%―2.67%, Al2O3 16.75%―21.52%, CaO 7.03%―11.13%, K2O 0.05%―0.38%; the REE pattern is slight depletion or flat, and the trace spider diagram is like that of N-MORB, so we consider that the metabasite was formed under the setting of mid-ocean ridge or adult back-arc basin, and it is the fragment of Paleo-Tethys ophiolite.ZHAI QingGuo1,2, LI Cai2 & HUANG XiaoPeng2 1 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2 College of Earth Sciences, Jilin University, Changchun 130061, China 2007Science China Earth Sciences2007,50,9:32
12The vegetation and climate change during Neocene and Early Quaternary in Jiuxi Basin, China显示文摘Sporopollen record in the Laojunmiao Section at Yumen in the Hexi Corridor foreland depression at the northern margin of the Tibetan Plateau revealed that during the period of 13.0―11.15 Ma the ecological environment of the Jiuxi Basin is characterized by steppe vegetation and a semi-moist climate. During 11.16―8.60 Ma prevailed forests of cypress and a still warmer, moister climate; steppe vegetation and dry climate began probably at about 8.6 Ma. Although aridification had been relaxed time and again during 8.40―6.93 Ma (forest-steppe, warm-semi-moist), 6.64―5.67 Ma (open-forest and steppe, warmer-semi-moist) and 5.42―4.96 Ma (steppe, semi-arid), the climate in the region became drier and drier in response to the fre- quent occurrence of aridity during 6.93―6.64 Ma (steppe, semi-arid), 5.67―5.42 Ma (de- sert-steppe, arid), 3.66―3.30 Ma (desert-steppe, arid) and 2.56―2.21 Ma (desert, arid). Perhaps the important findings of our study are the notable expansion of drought-enduring plants during 3.66―3.30 Ma and about 2.56 Ma and the replacement of vegetation by vast arid desert.MA Yuzhen 1 , FANG Xiaomin 1,2 , LI Jijun 1 , WU Fuli 1 & ZHANG Jun 1 1. Key Laboratory of Western China’s Environmental Systems and College of Resources and Environment, Lanzhou University, Lanzhou 730000, China 2. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2005Science China Earth Sciences2005,48,5:31
13Hyaluronic acid fragments evoke Kupffer cells via TLR4 signaling pathway显示文摘Kupffer cells, expressing toll-like receptor 4 (TLR4), play a central role in hepatic ischemia/reperfusion (I/R) injury. Hyaluronic acid (HA) fragments, degradative products of high-molecular-weight HA (HMW-HA), acquire the ability to activate immune cells under inflammatory conditions. Here we inves- tigated whether HA fragments could activate Kupffer cells and analyzed the underlying mechanism. Kupffer cells were isolated from wild-type mice (WT, C3H/HeN) and TLR4 mutant mice (C3H/HeJ) and HA fragments were produced by the methods of enzyme digestion and chromatography. Then Kupffer cells were stimulated by HA fragments or other control stimuli. The activation of Kupffer cells was estimated as the release of pro-inflammatory cytokines. The activation of p38 MAPK pathway of Kupffer cells was checked and blocking experiments were done as well. The results indicated that HA fragments acquired the ability to activate Kupffer cells in vitro, which was TLR4 dependent and not due to contamination of lipopolysaccharide. Experiments of p38 MAPK kinase inhibition by SB-203580 verified p38 MAPK was required in HA fragments induced Kupffer cells activation. This suggests that HA fragments, degradative products of one of the major glycosaminoglycans of the extracellular matrix, play critical roles in Kupffer cell activation mediated by TLR4 signaling pathway, which is, at least partially, de- pendent on p38 MAPK activation.ZHANG JinXiang1, WANG Hui2, XIAO Qing3, LIANG HuiFang4, LI ZhuoYa4, JIANG ChunFang1, WU HeShui5 & ZHENG QiChang5 1 Department of Emergency Surgery, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 2 Department of Medical Genetics, Tongji Medical College Affiliated to Huazhong University of Science and Technology, Wuhan 430030, China 3 Department of Ophthalmology, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 4 Department of Medical Immunology, Tongji Medical College Affiliated to Huazhong University of Science and Technology, Wuhan 430030, China 5 Department of General Surgery, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 2009Science China(Life Sciences)2009,52,2:33
14SHRIMP U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang, northern Tibetan Plateau显示文摘Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.282615 to 0.282657, with εHf(t) values of 5.02±0.28, indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the 'Central Uplift' of the Qiangtang, northern Tibetan Plateau.ZHAI QingGuo1 WANG Jun1, LI Cai2 & SU Li3 1 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2 College of Earth Sciences, Jilin University, Changchun 130061, China 3 The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources, China University of Geo- sciences, Beijing 100083, China 2010Science China Earth Sciences2010,53,5:31
15Assessment of candidate plant DNA barcodes using the Rutaceae family显示文摘DNA barcoding is a rapidly developing frontier technology that is gaining worldwide attention.Here,seven regions (psbA-trnH,matK,ycf5,rpoC1,rbcL,ITS2,and ITS) with potential for use as DNA barcodes were tested for their ability to identify 300 samples of 192 species from 72 genera of the family Rutaceae.To evaluate each barcode’s utility for species authentication,PCR amplification efficiency,genetic divergence,and barcoding gaps were assessed.We found that the ITS2 region exhibited the highest inter-specific divergence,and that this was significantly higher than the intra-specific variation in the 'DNA barcoding gap' assessment and Wilcoxon two-sample tests.The ITS2 locus had the highest identification efficiency among all tested regions.In a previous study,we found that ITS2 was able to discriminate a wide range of plant taxa,and here we confirmed that ITS2 was also able to discriminate a number of closely related species.Therefore,we propose that ITS2 is a promising candidate barcode for plant species identification.LUO Kun1,2,CHEN ShiLin1,CHEN KeLi2,SONG JingYuan1,YAO Hui1,MA XinYe1,ZHU YingJie3,PANG XiaoHui1,YU Hua1,LI XiWen1,4 & LIU Zhen2 1Institute of Medicinal Plant Development,Peking Union Medical College,Chinese Academy of Medical Sciences,Beijing 100193,China 2College of Pharmacy,Hubei University of Chinese Medicine,Wuhan 430061,China 3School of Bioscience and Engineering,Southwest Jiaotong University,Chengdu 610031,China 4Department of Chemistry,Tsinghua University,Beijing 100084,China 2010Science China(Life Sciences)2010,53,6:32
16Dissection 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 2008Science China(Life Sciences)2008,51,7:32
17Energy analysis for damage and catastrophic failure of rocks显示文摘The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of energy.The main scope and the achievable objectives of the energy-based research system were expatiated.It was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy dissipation.It was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak load.For both hard and soft rocks,the energy dissipated after peak load accounts for a greater proportion.More energy would be required for rock failure under equal biaxial compression than under unequal biaxial compression.The total absorbed energy is different for rock failure under high-rate loading and low-rate loading.More fragmented failure pattern usually corresponds to higher energy absorption.The mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt rock.The energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics theory.Furthermore,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated numerically.It was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks.XIE HePing 1,2,LI LiYun 2,1,JU Yang 2,PENG RuiDong 2 & YANG YongMing 2 1 Sichuan University,Chengdu 610065,China 2 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,China University of Mining and Technology,Beijing 100083,China 2011Science China(Technological Sciences)2011,54,S1:29
18The intracellular mechanism of alpha-fetoprotein promoting the proliferation of NIH 3T3 cells显示文摘AIM The existence and properties of alpha-fetoprotein (AFP) receptor on the surface of NIH 3T3 cells and the effects of AFP on cellular signal transduction pathway were investigated. METHODS The effect of AFP on the proliferation of NIH 3T3 cells was measured by incorporation of 3H-TdR. Receptor-binding assay of 125I-AFP was performed to detect the properties of AFP receptor in NIH 3T3 cells. The influences of AFP on the [cAMP]i and the activities of protein kinase A (PKA) were determined. Western blot was used to detect the change of K-ras P21 protein expression. RESULTS The proliferation of NIH 3T3 cells treated with 0-80 mg/L of AFP was significantly enhanced. The Scatchard analysis indicated that there were two classes of binding sites with KD of 2.722×10-9M (Bmax=12810 sites per cell) and 8.931× 10-SM (Bmax=l19700 sites per cell) respectively. In the presence of AFP (20 mg/L), the content of cAMP and activities of PKA were significantly elevated . The level of K-ras P21 protein was upregulated by AFP at the concentration of 20 mg/L. The monoclonal antibody against AFP could reverse the effects of AFP on the cAMP content, PKA activity and the expression of K-ras p21 gene. CONCLUSION The effect of AFP on the cell proliferation was achieved by binding its receptor to trigger the signal transduction pathway of cAMP-PKA and alter the expression of K- ras p21 gene.MENG SEN LI, PING FENG LI, FBI YI YANG, SHI PENG HE, Guo GUANG DU, GANG LI1 Department of Biochemistry and Molecular Biology, 2 Department of Biophysics, Health Science Center, Peking University, Beijing 100083, China 2002Cell Research2002,12,2:27
19Review on hidden trouble detection and health diagnosis of hydraulic concrete structures显示文摘A large number of hydraulic concrete structures have hidden defects such as cracks, erosion, freeze and thaw, thermal fatigue, carbonization. These hidden defects seriously affect the strength, stability and durability of structures. These problems are studied mainly by single monitoring or diagnosis methods at present. The integration of multiple monitoring and diagnosis methods is not applied widely. Besides, the analysis theory on these problems is not developed very well. The systemic study on the aging mechanism of hydraulic concrete structures, time- variation model and health diagnosis is still not enough. The support for engineering practice is limited. Aimed at these major scientific and technological problems and combined with specific projects, study on detection of hidden defects and health diagnosis of hydraulic concrete structure has been carried out. This study includes the following content: field non-destructive examination of hidden defects of hydraulic concrete structures, seepage detection, the construction of in-situ sensing system, the combination of field detection and in-situ monitoring, the mechanism of crack, freeze and thaw, erosion and carbonization of hydraulic concrete structure, mechanism of combination aging; time-variation model of hydraulic concrete structure, theories and methods for health diagnosis of hydraulic concrete structures.WU ZhongRu1,2?, LI Ji1, GU ChongShi1,2 & SU HuaiZhi1,2 1 College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Nanjing 210098, China 2007Science China(Technological Sciences)2007,50,z1:27
20Next-generation sequencing technology:A technology review and future perspective显示文摘As one of the most powerful tools in biomedical research,DNA sequencing not only has been improving its productivity at an exponential growth rate but has also been evolving into a new layout of technological territories toward engineering and physical disciplines over the past three decades.In this technical review,we look into technical characteristics of the next-generation sequencers and provide insights into their future development and applications.We envisage that some of the emerging platforms are capable of supporting the USD1000 genome and USD100 genome goals if given a few years for technical maturation.We also suggest that scientists from China should play an active role in this campaign that will have a profound impact on both scientific research and societal healthcare systems.ZHOU XiaoGuang1,REN LuFeng1,LI YunTao2,ZHANG Meng1,YU YuDe2 & YU Jun1 1 Key Laboratory of Genome Sciences and Information,Beijing Institute of Genomics,Chinese Academy of Sciences,Beijing 100029,China 2 Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,China 2010Science China(Life Sciences)2010,53,1:27
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