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    题名 作者 年代 出处 被引量
1Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s显示文摘Land-use/land-cover 变化(LUCC ) 有连接到人和自然相互作用。瓷器 Land-Use/cover 数据集(CLUD ) 从 1980 年代末在 5 年的间隔定期被更新到 2010,与基于 Landsat TMETM+ 图象的标准过程。陆地使用动态区域化方法被建议分析主要陆地使用变换。在国家规模的陆地使用变化的空间与时间的特征,差别,和原因然后被检验。主要调查结果如下被总结。越过中国的陆地使用变化(LUC ) 在最后 20 年(19902010 ) 里在空间、时间的特征显示了一个重要变化。农田变化的区域在南方减少了并且在北方,而是仍然是的全部的区域增加了几乎未改变。回收农田从东北被转移到西北。布满建筑物陆地很快膨胀了,主要在东方被散布,并且逐渐地展开到中央、西方的中国。树林首先减少了,然后增加但是荒芜的区域是反面。草地继续减少。在中国的 LUC 的不同空间模式被发现在之间迟了第 20 世纪并且早第 21 世纪。原版 13 个 LUC 地区在一些地区被边界的变化由 15 个单位代替。包括的这些变化(1 ) 的主要空间特征加速的扩大布满建筑物在 Huang-Huai-Hai 区域,东南的沿海的区域,长江的中流区域,和四川盆登陆;(2 ) 从东北中国和东方内部蒙古在北方转移了陆地开垦到绿洲在西北中国的农业区域;(3 ) 从在到稻的东北中国的喂雨的农田的连续转变回答;并且(4 ) 为在内部蒙古,黄土高原,和西南的多山的区域的南部的农业牧剧的交错群落的格林工程的谷物的有效性。在最后二十年,尽管在北方的气候变化在农田影响了变化,政策规定和经济驱动力仍然是越过中国的 LUC 的主要原因。在第 21 世纪的第一十年期间,在陆地使用模式驾驶了变化的人为的因素从单程的陆地开发转移了强调到开发和保存。动态区域化方法被用来在单位的 zoning 边界,地区的内部特征,和生长和减少的空间模式分析变化。结果揭示了变化过程的模式,也就是 LUC 的过程和在在不同阶段的特征的地区性的差别。地区的生长和减少在这动态 LUC zoning,在统一边界的变化,和在前者和后者十年之间的变化紧张的特征期间被检验。在为在不同类型和陆地使用的不同区域的变化的陆地使用和原因的模式和过程之间的其他的转变的模式被探索。LIU Jiyuan KUANG Wenhui ZHANG Zengxiang XU Xinliang QIN Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng 2014Journal of Geographical Sciences2014,24,2:245
2Massive individual orbital angular momentum channels for multiplexing enabled by Dammann gratings显示文摘Data transmission rates in optical communication systems are approaching the limits of conventional multiplexing methods.Orbital angular momentum(OAM)in optical vortex beams offers a new degree of freedom and the potential to increase the capacity of free-space optical communication systems,with OAM beams acting as information carriers for OAM division multiplexing(OAM-DM).We demonstrate independent collinear OAM channel generation,transmission and simultaneous detection using Dammann optical vortex gratings(DOVGs).We achieve 80/160 Tbit s^(-1) capacity with uniform power distributions along all channels,with 1600 individually modulated quadrature phase-shift keying(QPSK)/16-QAM data channels multiplexed by 10 OAM states,80 wavelengths and two polarizations.DOVG-enabled OAM multiplexing technology removes the bottleneck of massive OAM state parallel detection and offers an opportunity to raise optical communication systems capacity to Pbit s^(-1) level.Ting Lei Meng Zhang Yuru Li Ping Jia Gordon Ning Liu Xiaogeng Xu Zhaohui Li Changjun Min Jiao Lin Changyuan Yu Hanben Niu Xiaocong Yuan 2015Light(Science & Applications)2015,4,1:47
3Fundus artery occlusion caused by cosmetic facial injections显示文摘Chen Yanyun Wang Wenying Li Jipeng Yu Yajie Li Lin Lu Ning 2014Chinese Medical Journal2014,,8:35
4Electroacupuncture in the repair of spinal cord injury:inhibiting the Notch signaling pathway and promoting neural stem cell proliferation显示文摘Electroacupuncture for the treatment of spinal cord injury has a good clinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Dawley rats was clamped for 60 seconds. Dazhui(GV14) and Mingmen(GV4) acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expression of serum inflammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These findings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem cells.Xin Geng Tao Sun Jing-hui Li Ning Zhao Yong Wang Hua-lin Yu 2015Neural Regeneration Research2015,10,3:33
5PROTAC-induced BTK degradation as a novel therapy for mutated BTK C481S induced ibrutinib-resistant B-cell malignancies显示文摘Yonghui Sun Xingwang Zhao Ning Ding Hongying Gao Yue Wu Yiqing Yang Meng Zhao Jinseok Hwang Yuqin Song Wanli Liu Yu Rao 2018Cell Research2018,28,7:29
6Gynura root induces hepatic veno-occlusive disease:A case report and review of the literature显示文摘Gynura root has been used extensively in Chinese folk medicine and plays a role in promoting microcirculation and relieving pain.However,its hepatic toxicity should not be neglected.Recently,we admitted a 62-year old female who developed hepatic veno-occlusive disease(HVOD)after ingestion of Gynura root.Only a few articles on HVOD induced by Gynura root have been reported in the literature.It is suspected that pyrrolizidine alkaloids in Gynura root might be responsible for HVOD.In this paper,we report a case of HVOD and review the literature.Ning Dai Ying-Cong Yu Tian-Hua Ren Jia-Guo Wu Yuan Jiang Lai-Gen Shen Jing Zhang 2007World Journal of Gastroenterology2007,13,10:27
7Changes of Urban Wetland Landscape Pattern and Impacts of Urbanization on Wetland in Wuhan City显示文摘In this study,remote sensing data of Wuhan City,Hubei Province,China in 1996-2001 were selected to ex-tract wetland landscape information.Several landscape indices were used to evaluate the changes of landscape pattern within the five years,including patch number,patch density,patch fractal dimension,landscape diversity,dominance,evenness,and fragmentation indexes.Then,transformation probabilities of wetland landscapes into non-wetland land-scapes were calculated based on Markov Model,and on these grounds the relationship between changes of wetland landscape pattern and urban construction was analyzed.The results showed that fragmentation degree of all wetland types increased,lake area declined,and dominance of natural wetland decreased.The reasons for these results were mainly because of urban construction.According to the features of abundant wetland in Wuhan City,we suggested that protection of wetland landscape should cooperate with urban construction,which means wetland should become im-portant part of urban landscape.WANG Xuelei NING Longmei YU Jing XIAO Rui LI Tao 2008Chinese Geographical Science2008,18,1:27
8Therapeutic effect of acupuncture and massage for shoulder-hand syndrome in hemiplegia patients:a clinical two-center randomized controlled trial显示文摘OBJECTIVE:To evaluate the therapeutic effects of acupuncture and massage for shoulder-hand syndrome in hemiplegia patients.METHODS:One hundred and twenty hemiplegia patients with stage I shoulder-hand syndrome were randomly divided into a group treated with standardized electric acupuncture and massage,and a group treated with rehabilitation therapy for 6 weeks.The primary indices evaluated were pain on passive movement of the shoulder using the numeric pain rating scale(NPRS),and the number of patients with shoulder-hand syndrome at Steinbrocker stage II or III after treatment.The secondary indices were Fugl-Meyer evaluation of functional movement of the upper limb and hand using the modified rankin scale(MRS).RESULTS:At post-treatment evaluation and a 12-week follow-up visit,NPRS score,number of patients with stage II or III shoulder-hand syndrome,and MRS score were all improved in the acupuncture-massage group compared with the rehabilitation group(P<0.05).On Fugl-Meyer evaluation,functional movement of the upper limb was also improved in the acupuncture-massage group compared with the rehabilitation group(P<0.05).CONCLUSION:Standardized acupuncture-massage therapy may have curative effects on shoulder-hand syndrome in hemiplegia patients.Ning Li Fengwei Tian Chengwei Wang Pengming Yu Xi Zhou Qian Wen Xiulan Qiao Lu Huang 2012Journal of Traditional Chinese Medicine2012,32,3:25
9Clinical curative effect of electric acupuncture on acute cerebral infarction:a randomized controlled multicenter trial显示文摘OBJECTIVE: To examine whether electric acupuncture can improve the daily life of patients with ischemic cerebral apoplexy at acute stage.METHODS: A stratified-block randomized controlled multicenter trial was designed for this study.Totally 340 patients with acute ischemic cerebral apoplexy were randomly divided into an electric acupuncture group and a control group. In the electric acupuncture group, 170 patients were treated with electric acupuncture and routine therapy, and170 patients in the control group with routine therapy alone. Major indexes for judging curative effect were Barthel index at 3- and 6- months follow-up visits and number of re-hospitalized patients. Mi-nor indexes for judging curative effect were change in the score for nervous dysfunction at 4and 12 weeks follow-up visits and number of patients persisting in rehabilitation treatment with acupuncture during follow-up visit.RESULTS: Baseline data at the time of case selection between the two groups were similar. The odds ratio(OR) was 0.92, and the 95% confidence interval(CI) was 0.49-1.73 in disabled rate and 0.73 and 0.51-1.05 in the number of re-hospitalized patients in the electric acupuncture group at 6-month follow up visit compared with the control group.There was no difference in the score for nervous dysfunction at the end of 12-week follow-up visit between the two groups. The score for nervous dysfunction at the end of 4-week treatment in the electric acupuncture group was significantly higher than that in the control group(P<0.05). The number of patients discharged from hospital who persisted in rehabilitation treatment with acupuncture in the acupuncture group was significantly higher than that in the control group.CONCLUSION: Using electric acupuncture to treat patients with acute ischemic cerebral apoplexy can effectively improve the nervous dysfunction scores after 4-week treatment and their ability to deal with daily life after 6-month follow-up visit. Systematic treatment with acupuncture may also reduce the number of patients with secondary apoplexy.Chengwei Wang Zhongchao Wu Ning Li Yu Zhao Fengwei Tian Xi Zhou Zhuxing Wang 2014Journal of Traditional Chinese Medicine2014,34,6:22
10Relationship between tumor necrosis factor-α and liver fibrosis显示文摘RelationshipbetweentumornecrosisfactorαandliverfibrosisWANGXin,CHENYueXiang,XUCaiFu,ZHAOGuoNing,HUANGYuXinandWANGQinLiD...WANG Xin, CHEN Yue Xiang, XU Cai Fu, ZHAO Guo Ning, HUANG Yu Xin and WANG Qin Li Department of Gastroenterology, Tangdu Hospital, The Fourth Military Medical University, Xi′an 710038, Shaanxi Province, China 1998World Journal of Gastroenterology1998,4,1:21
11Crystal structure and biochemical analyses reveal Beclin 1 as a novel membrane binding protein显示文摘Beclin 1 基因是 haplo 不够的肿瘤 suppressor 并且在 autophagy 起一个必要作用。然而, Beclin 1 由工作的分子的机制仍然保持大部分未知。这里,我们在 1.6 Å 报导 Beclin 1 的 evolutionarily 保存的领域(ECD ) 的水晶结构;分辨率。Beclin 1 ECD 展览一以前 unreported 褶层,与在中央轴附近相称性地安排的三次结构的重复。Beclin 1 ECD 定义膜绑定领域的一个新奇的类,与为与 cardiolipin 充实的类脂化合物膜的强壮的偏爱。在 Beclin 1 ECD 的一个表面环的尖端,包括三芳香的氨基酸,与类脂化合物膜充当一根恐水病的手指到伙伴,因而导致膜和 liposomes 的变丑。这些芳香的残余的变化使 Beclin 1 变为不能稳定地在 vitro 与类脂化合物膜联系并且不能充分在 vivo 在 Beclin 1-knockdown 房间救 autophagy。这些观察为译解形成一个重要框架 Beclin 1 的生物功能。Weljlao Huang Wooyoung Chol Wanqiu Hu Na Mi Qiang Guo Meisheng Ma Mei Liu Yuan Tian Peilong Lu Feng-Liang Wang Haiteng Deng Lei Liu Ning Gao Li Yu Yigong Shi 2012Cell Research2012,22,3:21
12Curative effect of heat-sensitive moxibustion on chronic persistent asthma: a multicenter randomized controlled trial显示文摘OBJECTIVE:To compare the curative effects of heat-sensitive moxibustion with conventional drugs on chronic persistent asthma and seek a valuable therapy to replaceWestern Medicine.METHODS:The participants in this multi-center,randomized,and controlled study were randomly divided into two groups:group A(n=144),treated with heat-sensitive moxibustion(50 sessions)and group B(n=144),treated with Seretide(salmeterol50μg/fluticasone 250μg,twice a day).The scores of asthma control test(ACT),forced expiratory volume in 1 second(FEV1),peak expiratory flow(PEF),and attack frequency were measured after 15,30,60,and 90 days of treatment.Patients followed up3 and 6 months after treatment.RESULTS:There was a significant difference(P=0.0002)in the ACT score and lung function between the two groups after 3 months of treatment and(P=0.000 03)during the follow-up visits.In addition,heat-sensitive moxibustion reduced attack frequency in the period from inclusion to the6-month follow-up visit.CONCLUSION:This study shows that heat-sensitive moxibustion may have a comparable curative effect toSeretide(salmeterol/fluticasone)on asthma.Rixin Chen Mingren Chen Jun Xiong Zhenhai Chi B0 Zhang Ning Tian Zhenhua Xu Tangfa Zhang Wanyao Li Wei Zhang Xiaofeng Rong Zhen Wang Gang Sun Baohe Ge Guoxiong Yu Nanchang Song 2013Journal of Traditional Chinese Medicine2013,33,5:20
13The ChinaMAP analytics of deep whole genome sequences in 10,588 individuals显示文摘Metabolic diseases are the most common and rapidly growing health issues worldwide.The massive population-based human genetics is crucial for the precise prevention and intervention of metabolic disorders.The China Metabolic Analytics Project(ChinaMAP)is based on cohort studies across diverse regions and ethnic groups with metabolic phenotypic data in China.Here,we describe the centralized analysis of the deep whole genome sequencing data and the genetic bases of metabolic traits in 10,588 individuals from the ChinaMAP.The frequency spectrum of variants,population structure,pathogenic variants and novel genomic characteristics were analyzed.The individual genetic evaluations of Mendelian diseases,nutrition and drug metabolism,and traits of blood glucose and BMI were integrated.Our study establishes a large-scale and deep resource for the genetics of East Asians and provides opportunities for novel genetic discoveries of metabolic characteristics and disorders.Yanan Cao Lin Li Min Xu Zhimin Feng Xiaohui Sun Jieli Lu Yu Xu Peina Du Tiange Wang Ruying Hu Zhen Ye Lixin Shi Xulei Tang Li Yan Zhengnan Gao Gang Chen Yinfei Zhang Lulu Chen Guang Ning Yufang Bi Weiqing Wang The ChinaMAP Consortium 2020Cell Research2020,30,9:20
14Safety and efficacy of ciprofol vs.propofol for sedation in intensive care unit patients with mechanical ventilation:a multi-center,open label,randomized,phase 2 trial显示文摘Background:Ciprofol(HSK3486;Haisco Pharmaceutical Group Co.,Ltd.,Chengdu,China),developed as a novel 2,6-disubstituted phenol derivative showed similar tolerability and efficacy characteristics as propofol when applicated as continuous intravenous infusion for 12 h maintenance sedation in a previous phase 1 trial.The phase 2 trial was designed to investigate the safety,efficacy,and pharmacokinetic characteristics of ciprofol for sedation of patients undergoing mechanical ventilation.Methods:In this multicenter,open label,randomized,propofol positive-controlled,phase 2 trial,39 Chinese intensive care unit patients receiving mechanical ventilation were enrolled and randomly assigned to a ciprofol or propofol group in a 2:1 ratio.The ciprofol infusion was started with a loading infusion of 0.1-0.2 mg/kg for 0.5-5.0 min,followed by an initial maintenance infusion rate of 0.30 mg·kg^(-1)·h^(-1),which could be adjusted to an infusion rate of 0.06 to 0.80 mg·kg^(-1)·h^(-1),whereas for propofol the loading infusion dose was 0.5-1.0 mg/kg for 0.5-5.0 min,followed by an initial maintenance infusion rate of 1.50 mg·kg^(-1)·h^(-1),which could be adjusted to 0.30-4.00 mg·kg^(-1)·h^(-1)to achieve-2 to+1 Richmond Agitation-Sedation Scale sedation within 6-24 h of drug administration.Results:Of the 39 enrolled patients,36 completed the trial.The median(min,max)of the average time to sedation compliance values for ciprofol and propofol were 60.0(52.6,60.0)min and 60.0(55.2,60.0)min,with median difference of 0.00(95%confidence interval:0.00,0.00).In total,29(74.4%)patients comprising 18(69.2%)in the ciprofol and 11(84.6%)in the propofol group experienced 86 treatment emergent adverse events(TEAEs),the majority being of severity grade 1 or 2.Drug-and sedation-related TEAEs were hypotension(7.7%vs.23.1%,P=0.310)and sinus bradycardia(3.8%vs.7.7%,P=1.000)in the ciprofol and propofol groups,respectively.The plasma concentration-time curves for ciprofol and propofol were similar.Conclusions:ciprofol is comparable to propofol with good tolerance and efficacy for sedation of Chinese intensive care unit patients undergoing mechanical ventilation in the present study setting.Trial registration:ClinicalTrials.gov,NCT04147416.Yongjun Liu Xiangyou Yu Duming Zhu Jun Zeng Qinhan Lin Bin Zang Chuanxi Chen Ning Liu Xiao Liu Wei Gao Xiangdong Guan 2022Chinese Medical Journal2022,,9:19
15Influence of acute hyperglycemia in human sepsis on inflammatory cytokine and counterregulatory hormone concentrations显示文摘AIM: In human sepsis, a prominent component of the hypermetabolite is impaired glucose tolerance (IGT) and hyperglycemia. Elevations in plasma glucose concentration impair immune function by altering cytokine production from macrophages. We assessed the role of glucose in the regulation of circulating levels of insulin, glucagon, cortisol,IL-6 and TNF-α in human sepsis with normal or impaired glucose tolerance.METHODS: According to the results of intravenous glucose tolerance test, forty patients were classified into two groups: control group (n=20) and IGT group (n=20).Plasma glucose levels were acutely raised in two groups and maintained at 15 mmol/L for 3 hours. Plasma insulin,glucagon and cortisol levels were measured by radioimmunoassay, the levels of TNF-α and IL-6 were detected by ELISA.RESULTS: In IGT group, the fasting concentrations of plasma glucose, insulin, glucagon, cortisol, IL-6 and TNFα levels were significantly higher than those in control group (P<0.05). During clamp, the control group had a higher average amount of dextrose infusion than the IGT group (P<0.01). In control group, plasma insulin levels rose from a basal value to a peak at an hour (P<0.05) and maintained at high levels. Plasma glucagon levels descended from a basal value to the lowest level within an hour (P<0.01)and low levels were maintained throughout the clamp. In IGT group, plasma insulin was more significantly elevated (P<0.01), and plasma glucagon levels were not significantly declined. Plasma cortisol levels were not significantly changed in two groups. In control group, plasma IL-6 and TNF-α levels rose (P<0.01) within 2 hours of the clamp and returned to basal values at 3 hours. In IGT group, increased levels of plasma cytokine lasted longer than in control group (3 hours vs. 2 hours, P<0.05), and the cytokine peaks of IGT group were higher (P<0.05) than those of control group.CONCLUSION: Acute hyperglycemia pricks up hyperinsulinemia and increases circulating cytokine concentrations and these effects are more pronounced in sepsis with IGT. This suggests a potential modulation of immunoinflammatory responses in human sepsis by hyperglycemia.Wen-Kui Yu Wei-Qin Li Ning Li Jie-Shou Li, Medical College of Nanjing University, Research Institute of General Surgery, Jinling Hospital, Nanjing 210002, Jiangsu Province, China 2003World Journal of Gastroenterology2003,9,8:19
16Effect of endogenous insulin-like growth factor and stem cell factor on diabetic colonic dysmotility显示文摘AIM: To investigate whether the reduction of stem cell factor (SCF) is mediated by decreased endogenous insulin-like growth factor (IGF)-1 in diabetic rat colon smooth muscle. METHODS: Sixteen Sprague-Dawley rats were randomly divided into two groups: control group and streptozotocin-induced diabetic group. After 8 wk of streptozotocin administration, colonic motility function and contractility of circular muscle strips were measured. The expression of endogenous IGF-1 and SCF was tested in colonic tissues. Colonic smooth muscle cells were cultured from normal adult rats. IGF-1 siRNA transfection was used to investigate whether SCF expression was affected by endogenous IGF-1 expression in smooth muscle cells, and IGF-1 induced SCF expression effects were studied. The effect of high glucose on the expression of endogenous IGF-1 and SCF was also investigated. RESULTS: Diabetic rats showed prolonged colonic transit time (252 ± 16 min vs 168 ± 9 min, P < 0.01) and weakness of circular muscle contraction (0.81 ± 0.09 g vs 2.48 ± 0.23 g, P < 0.01) compared with the control group. Endogenous IGF-1 and SCF protein expression was significantly reduced in the diabetic colonic muscle tissues. IGF-1 and SCF mRNA expression also showed a paralleled reduction in diabetic rats. In the IGF-1 siRNA transfected smooth muscle cells, SCF mRNA and protein expression was significantly decreased. IGF-1 could induce SCF expression in a concentration and time-dependent manner, mainly through the extracellular-signal-regulated kinase 1/2 signal pathway. High glucose inhibited endogenous IGF-1 and SCF expression and the addition of IGF-1 to the medium reversed the SCF expression. CONCLUSION: Myopathy may resolve in colonic motility dysfunction in diabetic rats. Deficiency of endogenous IGF-1 in colonic smooth muscle cells leads to reduction of SCF expression.Yun Wang Xin-Yu Xu Yu-Rong Tang Wei-Wei Yang Yu-Feng Yuan Yue-Ji Ning Yin-Juan Yu Lin Lin 2013World Journal of Gastroenterology2013,19,21:18
17Association between Ambient Air Pollution and Hospital Emergency Admissions for Respiratory and Cardiovascular Diseases in Beijing: a Time Series Study显示文摘Objective To investigate the association between ambient air pollution and hospital emergency admissions in Beijing. Methods In this study, a semi-parametric generalized additive model(GAM) was used to evaluate the specific influences of air pollutants(PM10, SO2, and NO2) on hospital emergency admissions with different lag structures from 2009 to 2011, the sex and age specific influences of air pollution and the modifying effect of seasons on air pollution to analyze the possible interaction. Results It was found that a 10 μg/m3 increase in concentration of PM10 at lag 03 day, SO2 and NO2 at lag 0 day were associated with an increase of 0.88%, 0.76%, and 1.82% respectively in overall emergency admissions. A 10 μg/m3 increase in concentration of PM10, SO2 and NO2 at lag 5 day were associated with an increase of 1.39%, 1.56%, and 1.18% respectively in cardiovascular disease emergency admissions. For lag 02, a 10 μg/m3 increase in concentration of PM10, SO2 and NO2 were associated with 1.72%, 1.34%, and 2.57% increases respectively in respiratory disease emergency admissions. Conclusion This study further confirmed that short-term exposure to ambient air pollution was associated with increased risk of hospital emergency admissions in Beijing.ZHANG Ying WANG Shi Gong MA Yu Xia SHANG Ke Zheng CHENG Yi Fan LI Xu NING Gui Cai ZHAO Wen Jing LI Nai Rong 2015Biomedical and Environmental Sciences2015,28,5:18
18Numerical simulation of powder transport behavior in laser cladding with coaxial powder feeding显示文摘Laser cladding with coaxial powder feeding is one of the new processes applied to produce well bonding coating on the component to improve performance of its surface. In the process, the clad material is transported by the carrying gas through the coaxial nozzle, generating gas-powder flow. The powder feeding process in the coaxial laser cladding has important influence on the clad qualities. A 3D numerical model was developed to study the powder stream structure of a coaxial feeding nozzle. The predicted powder stream structure was well agreed with the experimental one. The validated model was used to explore the collision behavior of particles in the coaxial nozzle, as well as powder concentration distribution. It was found that the particle diameter and restitution coefficient greatly affect the velocity vector at outlet of nozzle due to the collisions, as well as the powder stream convergence characteristics below the nozzle. The results indicated a practical approach to optimize the powder stream for the coaxial laser cladding.LIU Hao HE XiuLi YU Gang WANG Zhong Bin LI ShaoXia ZHENG CaiYun NING WeiJian 2015Science China(Physics,Mechanics & Astronomy)2015,58,10:17
19Clinical and laboratory survey of 65 Chinese patients with Leigh syndrome显示文摘Background Leigh syndrome is an inherited neurodegenerative disease that emerges in infancy and childhood and presents with a clinically heterogeneous variety of neuromuscular and non-neuromuscular disorders. It can result from the inheritance of mutations in either nuclear or mitochondrial DNA. In the current study, we performed a retrospective study in 65 patients in order to investigate the clinical and genetic characteristics of Leigh syndrome in Chinese patients. Methods Sixty-five unrelated cases (35 men and 30 women) who were hospitalized in the past 12 years were reviewed. Diagnosis was based on both the clinical presentation and the characteristic neuropathologic findings of bilateral symmetric necrotizing lesions in the basal ganglia and brain stem as detected using cranial computed tomography (CT) scan or magnetic resonance imaging (MRI). The differential diagnosis of organic acidurias and fatty acid ?-oxidation defects were performed. Specific point mutations and deletions in mitochondrial DNA (T8993G, T8993C, T9176C, A8344G, A3243G) were screened by PCR-restriction analysis and Southern blot. The SURF1 gene was sequenced. Skeletal muscle biopsies were performed in 17 (26.2%) of the patients. The diagnosis was confirmed by autopsy in 6 (9.2%) patients. Results The patients had various forms of metabolic encephalomyopathy. Fifty-nine (90.8%) of the patients had the typical neuroradiological features of Leigh syndrome, including symmetrical necrotizing lesions scattered within the basal ganglia, thalamus and brain stem. Twenty (30.8%) patients were confirmed by genetic, biochemical analysis and autopsy. Specific point mutations in mitochondrial DNA were found in 5 cases (7.7%). Of these, the A8344G mutation was detected in 2 patients. The T8993G, T8993C, and A3243G point mutations were identified in 3 other patients, respectively. SURF1 mutations associated with cytochrome c oxidase deficiency were identified in 8 (12.3%) families by DNA sequencing. A G604C mutation was identified in 6 (9.2%) patients. The genotypes of 52 patients remained unknown. Conclusions Leigh syndrome presents as a diverse array of clinical features and can result from specific mutations in nuclear or mitochondrial DNA. In this study, SURF1 mutations associated with cytochrome c oxidase deficiency were identified in 8 (12.3%) out of 65 patients with Leigh syndrome. It indicates that SURF1 mutations might be a common cause of Leigh syndrome in China. The etiology of Leigh syndrome in Chinese patients represents a persistent challenge to clinicians.YANG Yan-ling SUN Fang ZHANG Yao QIAN Ning YUAN Yun WANG Zhao-xia QI Yu XIAO Jiang-xi WANG Xiao-ying QI Zhao-yue ZHANG Yue-hua JIANG Yu-wu BAO Xin-hua QIN Jiong WU Xi-ru 2006Chinese Medical Journal2006,,5:17
20COVID-19 Outbreak Caused by Contaminated Packaging of Imported Cold-Chain Products—Liaoning Province,China,July 2020显示文摘Summary What is known about this topic?Few major outbreaks of coronavirus disease 2019(COVID-19)have occurred in China after major nonpharmaceutical interventions and vaccines have been deployed and implemented.However,sporadic outbreaks that had high possibility to be linked to cold chain products were reported in several cities of China..What is added by this report?In July 2020,a COVID-19 outbreak occurred in Dalian,China.The investigations of this outbreak strongly suggested that the infection source was from COVID-19 virus-contaminated packaging of frozen seafood during inbound unloading personnel contact.What are the implications for public health practice?Virus contaminated paper surfaces could maintain infectivity for at least 17–24 days at-25℃.Exposure to COVID-19 virus-contaminated surfaces is a potential route for introducing the virus to a susceptible population.Countries with no domestic transmission of COVID-19 should consider introducing prevention strategies for both inbound travellers and imported goods.Several measures to prevent the introduction of the virus via cold-chain goods can be implemented.Huilai Ma1 Jianqun Zhang Ji Wang Ying Qin Cao Chen Yang Song Liang Wang Jun Meng Lingling Mao Fengqin Li Ning Li Jian Cai Yong Zhang Dayan Wang Yunting Xia Hong Wang Shaofeng Jiang Xiang Zhao Peihua Niu Wenjie Tan Tao Ma Yecheng Yao Naiying Mao Zhen Zhu Tianjiao Ji Qian Yang Baoying Huang Li Zhao Jianxing Yu Li Bai Shuangli Zhu Dongyan Wang Yan Zhang Yingwei Sun Mingchun Luan Yanhai Wang Haibo Sun Shihong Yang Zhijian Bo Xiang Ren Zhongjie Li George Fu Gao Wei Yao Wenqing Yao Zijian Feng Wenbo Xu 2021China CDC weekly2021,3,21:16
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