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1Isolation and characterization of H7N9 viruses from live poultry markets--Implication of the source of current H7N9 infection in humans显示文摘On March 31, 2013, the National Health and Family Planning Commission announced that human infections with a previously undescribed influenza A (H7N9) virus had occurred in Shanghai and Anhui Province, China. To investigate the possible origins of the H7N9 viruses causing these human infections, we collected 970 samples, including drinking water, soil, and cloacal and tracheal swabs of poultry from live poultry markets and poultry farms in Shanghai and Anhui Province. Twenty samples were positive for the H7N9 influenza virus. Notably, all 20 viruses were isolated from samples collected from live poultry markets in Shanghai. Phylogenetic analyses showed that the six internal genes of these novel human H7N9 viruses were derived from avian H9N2 viruses, but the ancestor of their HA and NA genes is uncertain. When we examined the phylogenetic relationship between the H7N9 isolates from live poultry markets and the viruses that caused the human infections, we found that they shared high homology across all eight gene segments. We thus identified the direct avian origin of the H7N9 influenza viruses that caused the human infections. Importantly, we observed that the H7N9 viruses isolated from humans had acquired critical mutations that made them more 'human-like'. It is therefore imperative to take strong measures to control the spread of H7N9 viruses in birds and humans to prevent further threats to human health.SHI JianZhong DENG GuoHua LIU PeiHong ZHOU JinPing GUAN LiZheng LI WenHui LI XuYong GUO Jing WANG GuoJun FAN Jun WANG JinLiang LI YuanYuan JIANG YongPing LIU LiLing TIAN GuoBin LI ChengJun CHEN HuaLan 2013Chinese Science Bulletin2013,58,16:85
2Prevalence of Nontraumatic Osteonecrosis of the Femoral Head and its Associated Risk Factors in the Chinese Population: Results from a Nationally Representative Survey显示文摘De-Wei Zhao Mang Yu Kai Hu Wei Wang Lei Yang Ben-Jie Wang Xiao-Hong Gao Yong-Ming Guo Yong-Qing Xu Yu-Shan Wei Si-Miao Tian Fan Yang Nan Wang Shi-Bo Huang Hui Xie Xiao-Wei Wei Hai-Shen Jiang Yu-Qiang Zang Jun Ai Yuan-Liang Chen Guang-Hua Lei Yu-Jin Li Geng Tia Zong-Sheng Li Yong Cao Li Ma 2015Chinese Medical Journal2015,,21:151
3Persistence and clearance of viral RNA in 2019 novel coronavirus disease rehabilitation patients显示文摘Background:A patient’s infectivity is determined by the presence of the virus in different body fluids,secretions,and excreta.The persistence and clearance of viral RNA from different specimens of patients with 2019 novel coronavirus disease(COVID-19)remain unclear.This study analyzed the clearance time and factors influencing 2019 novel coronavirus(2019-nCoV)RNA in different samples from patients with COVID-19,providing further evidence to improve the management of patients during convalescence.Methods:The clinical data and laboratory test results of convalescent patients with COVID-19 who were admitted to from January 20,2020 to February 10,2020 were collected retrospectively.The reverse transcription polymerase chain reaction(RT-PCR)results for patients’oropharyngeal swab,stool,urine,and serum samples were collected and analyzed.Convalescent patients refer to recovered non-febrile patients without respiratory symptoms who had two successive(minimum 24 h sampling interval)negative RT-PCR results for viral RNA from oropharyngeal swabs.The effects of cluster of differentiation 4(CD4)+T lymphocytes,inflammatory indicators,and glucocorticoid treatment on viral nucleic acid clearance were analyzed.Results:In the 292 confirmed cases,66 patients recovered after treatment and were included in our study.In total,28(42.4%)women and 38 men(57.6%)with a median age of 44.0(34.0-62.0)years were analyzed.After in-hospital treatment,patients’inflammatory indicators decreased with improved clinical condition.The median time from the onset of symptoms to first negative RT-PCR results for oropharyngeal swabs in convalescent patients was 9.5(6.0-11.0)days.By February 10,2020,11 convalescent patients(16.7%)still tested positive for viral RNA from stool specimens and the other 55 patients’stool specimens were negative for 2019-nCoV following a median duration of 11.0(9.0-16.0)days after symptom onset.Among these 55 patients,43 had a longer duration until stool specimens were negative for viral RNA than for throat swabs,with a median delay of 2.0(1.0-4.0)days.Results for only four(6.9%)urine samples were positive for viral nucleic acid out of 58 cases;viral RNA was still present in three patients’urine specimens after throat swabs were negative.Using a multiple linear regression model(F=2.669,P=0.044,and adjusted R2=0.122),the analysis showed that the CD4+T lymphocyte count may help predict the duration of viral RNA detection in patients’stools(t=-2.699,P=0.010).The duration of viral RNA detection from oropharyngeal swabs and fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group(15 days vs.8.0 days,respectively;t=2.550,P=0.013)and the duration of viral RNA detection in fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group(20 days vs.11 days,respectively;t=4.631,P<0.001).There was no statistically significant difference in inflammatory indicators between patients with positive fecal viral RNA test results and those with negative results(P>0.05).Conclusions:In brief,as the clearance of viral RNA in patients’stools was delayed compared to that in oropharyngeal swabs,it is important to identify viral RNA in feces during convalescence.Because of the delayed clearance of viral RNA in the glucocorticoid treatment group,glucocorticoids are not recommended in the treatment of COVID-19,especially for mild disease.The duration of RNA detection may relate to host cell immunity.Yun Ling Shui-Bao Xu Yi-Xiao Lin Di Tian Zhao-Qin Zhu Fa-Hui Dai Fan Wu Zhi-Gang Song Wei Huang Jun Chen Bi-Jie Hu Sheng Wang En-Qiang Mao Lei Zhu Wen-Hong Zhang Hong-Zhou Lu 2020Chinese Medical Journal2020,,9:58
4Karyotype Stability and Unbiased Fractionation in the Paleo-Allotetraploid Cucurbita Genomes显示文摘Honghe Sun Shan WU Guoyu Zhang Chen Jiao Shaogui Guo Yi Ren Jie Zhang Haiying Zhang Guoyi Gong Zhangcai Jia Fan Zhang Jiaxing Tian William J. Lucas Jeff J. Doyle Haizhen Li Zhangjun Fei Yong Xu 2017Molecular Plant2017,10,10:33
5Research progress on silicon/carbon composite anode materials for lithium-ion battery显示文摘Silicon(Si) has been considered as one of the most promising anode material for the next generation lithium-ion batteries(LIBs) with high energy densities, due to its high theoretical capacity, abundant availability and environmental friendliness. However, silicon materials with low intrinsic electric and ionic conductivity suffer from huge volume variation during lithiation/delithiation processes leading to the pulverization of Si and subsequently resulting in severe capacity fading of the electrodes. Coupling of Si with carbon(C) realizes a favorable combination of the two materials properties, such as high lithiation capacity of Si and excellent mechanical and conductive properties of C, making silicon/carbon composite(Si/C) ideal candidates for LIBs anodes. In this review, recent progresses of Si/C materials utilized in LIBs are summarized in terms of structural design principles, material synthesis methods, morphological characteristics and electrochemical performances by highlighting the material structures. The mechanisms behind the performance enhancement are also discussed. Moreover, other factors that affect the performance of Si/C anodes, such as prelithiation, electrolyte additives, and binders, are also discussed. We aim to present a full scope of the Si/C-based anodes, and help understand and design future structures of Si/C anodes in LIBs.Xiaohui Shen Zhanyuan Tian Ruijuan Fan Le Shao Dapeng Zhang Guolin Cao Liang Kou Yangzhi Bai 2018Journal of Energy Chemistry2018,27,4:29
6Pulsed Eddy Current Non-destructive Testing and Evaluation:A Review显示文摘Pulsed eddy current(PEC) non-destructive testing and evaluation(NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the literature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents,attempts for its modelling both analytically and numerically have been made by researchers around the world.This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT&E are also presented.Ali Sophian Guiyun Tian Mengbao Fan 2017Chinese Journal of Mechanical Engineering2017,30,3:27
7Fibrinogen-like protein 2 fibroleukin expression and its correlation with disease progression in murine hepatitis virus type 3-induced fulminant hepatitis and in patients with severe viral hepatitis B显示文摘AIM: To evaluate the expression of fibrinogenlike protein 2 (fgl2) and its correlation with disease progression in both mice and patients with severe viral hepatitis.METHODS: Balb/cJ or A/J mice were infected intraperitoneally (ip) with 100 PFU of murine hepatitis virus type 3 (MHV-3), liver and serum were harvested at 24, 48, and 72 h post infection for further use. Liver tissues were obtained from 23 patients with severe acute chronic (AOC) hepatitis B and 13 patients with mild chronic hepatitis B. Fourteen patients with mild chronic hepatitis B with cirrhosis and 4 liver donors served as normal controls. In addition, peripheral blood mononuclear cells (PBMC) were isolated from 30 patients (unpaired) with severe AOC hepatitis B and 10 healthy volunteers as controls. Procoagulant activity representing functional prothrombinaseactivity in PBMC and white blood cells was also assayed. A polyclonal antibody against fgl2 was used to detect the expression of both mouse and human fgl2 protein in liver samples as well as in PBMC by immunohistochemistry staining in a separate set of studies. Alanine aminotransferase (ALT) and total bilirubin (TBil) in serum were measured to assess the severity of liver injury.RESULTS: Histological changes were found in liver sections 12-24 h post MHV-3 infection in Balb/cJ mice.In association with changes in liver histology, marked elevations in serum ALT and TBil were observed. Mouse fgl2 (mfgl2) protein was detected in the endothelium of intrahepatic veins and hepatic sinusoids within the liver 24 h after MHV-3 infection. Liver tissues from the patients with severe AOC hepatitis B had classical pathological features of acute necroinflammation. Human fgl2 (hfgl2)was detected in 21 of 23 patients (91.30%)with severe AOC hepatitis B, while only 1 of 13 patients(7.69%) with mild chronic hepatitis B and cirrhosis had hfgl2 mRNA or protein expression. Twenty-eight of thirty patients (93.33%) with severe AOC hepatitis B and 1of 10 with mild chronic hepatitis B had detectable hfgl2expression in PBMC. No hfgl2 expression was found either in the liver tissue or in the PBMC from normal donors. There was a positive correlation between hfgl2expression and the severity of the liver disease as indicated by the levels of TBil. PCA significantly increased in PBMC in patients with severe AOC hepatitis B.CONCLUSION: The molecular and cellular results reported here in both mice and patients with severe viral hepatitis suggest that virus-induced hfgl2prothrombinase/fibroleukin expression and the coagulation activity associated with the encoded fgl2protein play a pivotal role in initiating severe hepatitis.The measurement of hfgl2/fibroleukin expression in PBMC may serve as a useful marker to monitor the severity of AOC hepatitis B and a target for therapeutic intervention.Chuan-Long Zhu Wei-Ming Yan Fan Zhu Yong-Fen Zhu Dong Xi De-Ying Tian Gary Levy Xiao-Ping Luo Qin Ning 2005World Journal of Gastroenterology2005,11,44:26
8Robot-assisted Percutaneous Pedicle Screw Placement Using Three-dimensional Fluoroscopy: A Preliminary Clinical Study显示文摘Wei Tian Ming-Xing Fan Ya-Jun Liu 2017Chinese Medical Journal2017,,13:26
9Minimal invasive microscopic tooth preparation in esthetic restoration: a specialist consensus显示文摘By removing a part of the structure,the tooth preparation provides restorative space,bonding surface,and finish line for various restorations on abutment.Preparation technique plays critical role in achieving the optimal result of tooth preparation.With successful application of microscope in endodontics for>30 years,there is a full expectation of microscopic dentistry.However,as relatively little progress has been made in the application of microscopic dentistry in prosthodontics,the following assumptions have been proposed:Is it suitable to choose the tooth preparation technique under the naked eye in the microscopic vision?Is there a more accurate preparation technology intended for the microscope?To obtain long-term stable therapeutic effects,is it much easier to achieve maximum tooth preservation and retinal protection and maintain periodontal tissue and oral function health under microscopic vision?Whether the microscopic prosthodontics is a gimmick or a breakthrough in obtaining an ideal tooth preparation should be resolved in microscopic tooth preparation.This article attempts to illustrate the concept,core elements,and indications of microscopic minimally invasive tooth preparation,physiological basis of dental pulp,periodontium and functions involved in tool preparation,position ergonomics and visual basis for dentists,comparison of tooth preparation by naked eyes and a microscope,and comparison of different designs of microscopic minimally invasive tooth preparation techniques.Furthermore,a clinical protocol for microscopic minimally invasive tooth preparation based on target restorative space guide plate has been put forward and new insights on the quantity and shape of microscopic minimally invasive tooth preparation has been provided.Haiyang Yu Yuwei Zhao Junying Li Tian Luo Jing Gao Hongchen Liu Weicai Liu Feng Liu Ke Zhao Fei Liu Chufan Ma Juergen MSetz Shanshan Liang Lin Fan Shanshan Gao Zhuoli Zhu Jiefei Shen Jian Wang Zhimin Zhu Xuedong Zhou 2019International Journal of Oral Science2019,11,4:25
10电针和经皮穴位电刺激技术在生殖医学中的应用:专家共识(英文)显示文摘本文从传统针刺治疗不孕症的选穴依据与现代电针/经皮穴位电刺激技术的相关原理着手,从最优刺激参数选择、穴位辨证、疗程与治疗次数的确定及基本原理等方面阐述了电针/经皮穴位电刺激技术在多囊卵巢综合症、取卵镇痛、卵巢储备功能降低、胚胎移植以及男性少/弱精症等生殖领域中的具体应用。首次对电针/经皮穴位电刺激技术在生殖领域优势病种中的应用进行了系统的分析和总结,在最优刺激参数选择、穴位辨证、疗程与治疗次数的确定等方面提出了一系列专家共识,并为临床实践提供了指导意见和理论依据。Fan QU Rong LI Wei SUN Ge LIN Rong ZHANG Jing YANG Li TIAN Guo-gang XING Hui JIANG Fei GONG Xiao-yan LIANG Yan MENG Jia-yin LIU Li-ying ZHOU Shu-yu WANG Yan WU Yi-jing HE Jia-yu YE Song-ping HAN Ji-sheng HAN 2017Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2017,18,3:24
11The Hardy Rubber Tree Genome Provides Insights into the Evolution of Polyisoprene Biosynthesis显示文摘Eucommia ulmoides,也叫的强壮的橡胶树,是一棵经济地重要的树;然而,它的染色体顺序的缺乏 ?限制基本生物研究和这植物种的应用研究。这里,我们在场它的 1.2-Gb 染色体的一个高质量的集会(支架 N50 ?=? 1.88 Mb ) 与至少 26 ? 为 E 的 723 预言的基因。ulmoides,顺序 Garryales 的首先定序的染色体,它用联合定序的 Illumina 的综合策略被获得,定序的 PacBio,和印射的 BioNano。作为到 lamiids 和 campanulids 的姐妹 taxon, E。ulmoides 经历了三倍由核心 eudicots 而是没有进一步整个染色体的复制分享了的一个古老的染色体 ? 在最后 1.25 亿年里。E。ulmoides 为涉及压力回答和第二等的代谢物的生合成的多重基因展出高表达式层次或基因数字扩大,它可以说明它的可观的环境适应性。与橡胶树(Hevea brasiliensis ) 相对照,它生产 cis 聚异式戊二我烯, E。ulmoides 演变综合经由 farnesyl diphosphate synthases (FPS ) 的长链的 trans 聚异式戊二我烯。而且, FPS 和橡胶延伸 factor/small 橡胶粒子蛋白质基因家庭从 H 独立地被扩展。brasiliensis 系。这些结果提供新卓见进 E. 的生物学 ? ulmoides 和聚异式戊二我烯生合成的起源。Ta-na Wuyun Lin Wang Huimin Liu Xuewen Wang Liangsheng Zhang Jeffrey L. Bennetzen Tiezhu Li Lirong Yang Panfeng Liu Lanying Du Lu Wang Mengzhen Huang Jun Qing Iili Zhu Wenquan Bao Hongguo Li Qingxin Du Jingle Zhu Hong Yang Shuguang Yang Hui Liu Hui Yue Jiang Hu Suoliang Yu Yu Tian Fan Liang Jingjing Hu Depeng Wang Ruiwen Gao Dejun Li Hongyan Du 2018Molecular Plant2018,11,3:24
12Three-dimensional morphometric analysis for hepatectomy of centrally located hepatocellular carcinoma:A pilot study显示文摘AIM: To describe a three-dimensional model(3DM) to accurately reconstruct anatomic relationships of centrally located hepatocellular carcinomas(HCCs).METHODS: From March 2013 to July 2014, reconstructions and visual simulations of centrally located HCCs were performed in 39 patients using a 3D subject-based computed tomography(CT) model with customdeveloped software. CT images were used for the 3D reconstruction of Couinaud's pedicles and hepatic veins, and the calculation of corresponding tumor territories and hepatic segments was performed using Yorktal DMIT software. The respective volume, surgical margin, and simulated virtual resection of tumors were also estimated by this model preoperatively. All patients were treated surgically and the results were retrospectively assessed. Clinical characteristics, imaging data, procedure variables, pathologic features, and postoperative data were recorded and compared to determine the reliability of the model.RESULTS: 3D reconstruction allowed stereoscopic identification of the spatial relationships between physiologic and pathologic structures, and offered quantifiable liver resection proposals based on individualized liver anatomy. The predicted values were consistent with the actual values for tumor mass volume(82.4 ± 109.1 m L vs 84.1 ± 108.9 m L, P = 0.910), surgical margin(10.1 ± 6.2 mm vs 9.1 ± 5.9 mm, P = 0.488), and maximum tumor diameter(4.61 ± 2.16 cm vs 4.53 ± 2.14 cm, P = 0.871). In addition,the number and extent of portal venous ramifications, as well as their relation to hepatic veins, were visualized. Preoperative planning based on simulated resection facilitated complete resection of large tumors located in the confluence of major vessels. And most of the predicted data were correlated with intraoperative findings.CONCLUSION: This 3DM provides quantitative morphometry of tumor masses and a stereo-relationship with adjacent structures, thus providing a promising technique for the management of centrally located HCCs.Fei Tian Jian-Xiong Wu Wei-Qi Rong Li-Ming Wang Fan Wu Wei-Bo Yu Song-Lin An Fa-Qiang Liu Li Feng Chao Bi Yun-He Liu 2015World Journal of Gastroenterology2015,21,15:21
13Precise nanomedicine for intelligent therapy of cancer显示文摘Precise nanomedicine has been extensively explored for efficient cancer imaging and targeted cancer therapy, as evidenced by a few breakthroughs in their preclinical and clinical explorations. Here, we demonstrate the recent advances of intelligent cancer nanomedicine, and discuss the comprehensive understanding of their structure-function relationship for smart and efficient cancer nanomedicine including various imaging and therapeutic applications, as well as nanotoxicity. In particular, a few emerging strategies that have advanced cancer nanomedicine are also highlighted as the emerging focus such as tumor imprisonment, supramolecular chemotherapy, and DNA nanorobot. The challenge and outlook of some scientific and engineering issues are also discussed in future development. We wish to highlight these new progress of precise nanomedicine with the ultimate goal to inspire more successful explorations of intelligent nanoparticles for future clinical translations.Huabing Chen Zhanjun Gu Hongwei An Chunying Chen Jie Chen Ran Cui Siqin Chen Weihai Chen Xuesi Chen Xiaoyuan Chen Zhuo Chen Baoquan Ding Qian Dong Qin Fan Ting Fu Dayong Hou Qiao Jiang Hengte Ke Xiqun Jiang Gang Liu Suping Li Tianyu Li Zhuang Liu Guangjun Nie Muhammad Ovais Daiwen Pang Nasha Qiu Youqing Shen Huayu Tian Chao Wang Hao Wang Ziqi Wang Huaping Xu Jiang-Fei Xu Xiangliang Yang Shuang Zhu Xianchuang Zheng Xianzheng Zhang Yanbing Zhao Weihong Tan Xi Zhang Yuliang Zhao 2018Science China Chemistry2018,61,12:19
14Clinical significance of gastrostomy for patients injury percutaneous endoscopic with severe craniocerebral显示文摘Tian Yong Du Hanggen Fan Chengpu Wang Cheng Zhang Guojun Chen Li Li Hongyu 2014Chinese Journal of Traumatology2014,17,6:18
15Prevalence of Developmental Dysplasia of the Hip in Chinese Adults: A Cross-sectional Survey显示文摘Feng-De Tian De-Wei Zhao Wei Wang Lin Guo Si-Miao Tian Ao Feng Fan Yang Dong-Yi Li 2017Chinese Medical Journal2017,,11:18
16Pollution of organic compounds and heavy metals in a coal gangue dump of the Gequan Coal Mine, China显示文摘Samples around a coal gangue dump of the Gequan Coal Mine were collected in April 2009. GC (gas chromatography) and GC/MS (gas chromatography/mass spectrometry) were employed to analyze the composition of organic matter in the samples. ICP-MS (inductively coupled plasma mass spectrometry) was used to determine the concentrations of heavy metals. The contents of organic extracts are within the range of 140-750 mg/kg. Alkand aro-ratios are relatively high. Compared to those of the background sample (GQ13 ), the contents of saturated hydrocarbon compounds in all the samples are relatively high. The contents of polycyclic aromatic hydrocarbons (PAHs) are relatively high with the distance getting closer to the coal gangue dump. These indicate that organic matter in the samples is from coal particles of the coal gangue dump. The distributions of heavy metals are very similar: the contents decrease with distance from the dump, which indicates that the harmful heavy metals from the coal gangue dump have polluted as thick as at least 500 m.FAN Jingsen SUN Yuzhuang LI Xinyu ZHAO Cunliang TIAN Duanxin SHAO Longyi WANG Jinxi 2013Chinese Journal Of Geochemistry2013,32,3:18
17Expressions of type I collagen, α2 integrin and β1 integrin in sclera of guinea pig with defocus myopia and inhibitory effects of bFGF on the formation of myopia显示文摘AIM:To investigate the expressions of type I collagen, α2 integrin and β1 integrin in the posterior sclera of guinea pigs with defocus myopia and whether basic fibroblast growth factor (bFGF) injection inhibits the formation and development of myopia by upregulating the expression of type I collagen, α2 integrin and β1 integrin. METHODS:After 14 days of treatment, the refractive state and axial length were measured and the levels of type I collagen, α2 integrin and β1 integrin were assayed in the posterior sclerae of groups of guinea pigs that wore a monocular-7D polymethylmethacrylate (PMMA) lens or had -7D lens wear followed by the peribulbar injection of Phosphate Buffer Solution (PBS) or bFGF. The untreated fellow eye served as a control. Guinea pigs with no treatment served as normal group. ·RESULTS:The results showed that 14 days of monocular defocus increased axial eye length and refraction, while bFGF delivery inhibited them markedly. Further, it was also found that the monocular-7D lens could decrease the levels of type I collagen, α2 integrin and β1 integrin expressions, while, unlike PBS, bFGF increased them significantly in comparison to contralateral control eyes and normal eyes. CONCLUSION:bFGF can prevent the formation anddevelopment of defocus myopia by upregulating the expressions of type I collagen, α2 integrin and β1 integrin. Taken together, our results demonstrate that bFGF promotes sclera remodeling to prevent myopia in guinea pigs.Xiao-Dan Tian Yong-Xia Cheng Gui-Bo Liu Su-Fen Guo Chun-Lei Fan Li-Hui Zhan Yan-Chun Xu 2013International Journal of Ophthalmology(English edition)2013,6,1:16
18Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation显示文摘The mass-front velocities of granular flows results from the joint action of particle size gradations and the underlying surfaces.However,because of the complexity of friction during flow movement,details such as the slope-toe impedance effects and momentum-transfer mechanisms have not been completely explained by theoretical analyses,numerical simulations,or field investigations.To study the mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradations we conducted model experiments that recorded the motion of rapid and long-runout rockslides or avalanches.Flume tests were conducted using slope angles of 25°,35°,45°,and 55° and three particle size gradations.The resulting mass-front motions consisted of three stages:acceleration,velocity maintenance,and deceleration.The existing methods of velocity prediction could not explain the slowing effect of the slope toe or the momentum-transfer steady velocity stage.When the slope angle increased from 25° to 55°,the mass-front velocities dropped significantly to between 44.4% and59.6% of the peak velocities and energy lossesincreased from 69.1% to 83.7% of the initial,respectively.The velocity maintenance stages occurred after the slope-toe and mass-front velocity fluctuations.During this stage,travel distances increased as the angles increased,but the average velocity was greatest at 45°.At a slope angle of 45°,as the median particle size increased,energy loss around the slope toe decreased,the efficiency of momentum transfer increased,and the distance of the velocity maintenance stage increased.We presented an improved average velocity formula for granular flow and a geometrical model of the energy along the flow line.FAN Xiao-yi TIAN Shu-jun ZHANG You-yi 2016Journal of Mountain Science2016,13,2:16
19Myocardial bridge-related coronary heart disease:Independent influencing factors and their predicting value显示文摘BACKGROUND Myocardial bridge(MB)will compress the mural coronary artery(MCA)during the systole and cause myocardial ischemia.In the diagnosis of coronary heart disease(CHD),because the structure of MB is difficult to be observed by coronary angiography(CAG),the clinical study of the influence of MB on CHD is lacking.With the advancement of computed tomography coronary angiography technology,detailed observations of the MB anatomy have realized.AIM To explore the main influencing factors of MB-related CHD and to find potential indicators for predicting MB-related CHD.METHODS A total of 1718 patients with suspected CHD due to the symptoms of myocardial ischemia were enrolled as subjects.Patients diagnosed with CHD were included in a CHD group,and patients with no significant abnormalities were included in a control group.In the CHD group,patients were divided into an MB-CHD subgroup if MB-related CHD was found.In the control group,patients were divided into a simple MB subgroup if MB was found.The patient's clinical data and MB-related indicators,including the branch of MB,MB type(superficial/deep type),MB length,MB thickness,systolic and diastolic compression of the MCA,and MCA systolic stenosis rate were recorded and compared.Logistic regression analysis was used to explore the independent influencing factors of MD-related CHD.ROC curve was used to analyze the diagnostic efficacy of potential indicators for MB-related CHD.RESULTS There were 1060 cases in the CHD group and 658 cases in the control group,and there were 236 cases in the MB-CHD subgroup and 52 cases in the simple MB subgroup.Multivariate logistic regression analysis showed that the combined MB had a significant effect on the occurrence of CHD(P<0.05).MB thickness,systolic compression,diastolic compression,and MCA systolic stenosis rate had significant effects on the occurrence of MB-related CHD(P<0.05).The area under the curve(AUC)of the combination of these influencing factors for the diagnosis of MB-related CHD was 0.959,which was significantly higher than the AUCs of the four indicators separately(P<0.05).The sensitivity was 97.06%and the specificity was 87.63%.CONCLUSION MB thickness,systolic compression,diastolic compression,and MCA systolic stenosis are independent influencing factors for MB-related CHD.The combination of these factors has potential diagnostic value for MB-related CHD.Dong-Hui Zhao Qian Fan Jun-Xia Ning Xin Wang Jia-Yu Tian 2019World Journal of Clinical Cases2019,7,15:16
20Clinical Observation of Transepithelial Corneal Collagen Cross-linking by Iontophoresis of Riboflavin in Treatment of Keratoconus显示文摘Purpose: To evaluate the efficacy and safety of transepithelial collagen cross-linking by iontophoretic delivery of riboflavin in treatment of progressive keratoconus.Methods:.Eleven patients(15 eyes) with progressive keratoconus were enrolled. After 0.1% riboflavin-distilled water solution was deliveried via transepithelial iontophpresis for 5 min with 1 m A current, and ultraviolet radiation(370 nm,.3 m W /cm2) was performed at a 1.5 cm distance for 30 min. The follow up were 6 months in all eyes. The uncorrected visual acuity, corrected visual acuity,endothelial cell counting, corneal thickness,.intraocular pressure, corneal curvature, corneal topography,.OCT and corneal opacity before and 6-month after surgery were analyzed.Results: At 6 month postoperatively, mean uncorrected visual acuity and corrected visual acuity changed from 0.36 to 0.30 and from 0.42 to 0.57 without statistical significance..The mean value of each index of corneal curvature declined without statistical significance.Kmax value dereased from 60.91 to59.91, and the astigmatism declined from 3.86 to 3.19. Central corneal thickness decreased from 460.93 μm to 455.40μm,.and thinnest corneal thickness declined from 450.87 μm to 440.60 μm with no statistical significance..Intraocular pressure was significantly elevated from 10.85 mm Hg to 12.62 mm Hg. Endothelial cell count did not change significantly. No corneal haze occurred. Mean depth of corneal demarcation line was 288.46 μm at 1 month postoperatively..Conclusion:.Transepithelial corneal collagen cross-linking by iontophoresis is effective and safe in the treatment of progressive keratoconus, and yields stable clinical outcomes during 6-month follow up..However,.long-term follow up is urgently required.Na Li Zhengjun Fan Xiujun Peng Xu Pang Chunyu Tian 2014Eye Science2014,29,3:15
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