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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
2The Chinese Society of Clinical Oncology(CSCO):Clinical guidelines for the diagnosis and treatment of gastric cancer,2021显示文摘There exist differences in the epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selections between gastric cancer patients from the Eastern and Western countries.The Chinese Society of Clinical Oncology(CSCO)has organized a panel of senior experts specializing in all sub-specialties of gastric cancer to compile a clinical guideline for the diagnosis and treatment of gastric cancer since 2016 and renews it annually.Taking into account regional differences,giving full consideration to the accessibility of diagnosis and treatment resources,these experts have conducted expert consensus judgment on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes in China.The 2021 CSCO Clinical Practice Guidelines for Gastric Cancer covers the diagnosis,treatment,follow-up,and screening of gastric cancer.Based on the 2020 version of the CSCO Chinese Gastric Cancer guidelines,this updated guideline integrates the results ofmajor clinical studies from China and overseas for the past year,focused on the inclusion of research data from the Chinese population for more personalized and clinically relevant recommendations.For the comprehensive treatment of non-metastatic gastric cancer,attentions were paid to neoadjuvant treatment.The value of perioperative chemotherapy is gradually becoming clearer and its recommendation level has been updated.For the comprehensive treatment of metastatic gastric cancer,recommendations for immunotherapy were included,and immune checkpoint inhibitors fromthird-line to the first-line of treatment for different patient groups with detailed notes are provided.Feng-Hua Wang Xiao-Tian Zhang Yuan-Fang Li Lei Tang Xiu-Juan Qu Jie-Er Ying Jun Zhang Ling-Yu Sun Rong-Bo Lin Hong Qiu Chang Wang Miao-Zhen Qiu Mu-Yan Cai QiWu Hao Liu Wen-Long Guan Ai-Ping Zhou Yu-Jing Zhang Tian-Shu Liu Feng Bi Xiang-Lin Yuan Sheng-Xiang Rao Yan Xin Wei-Qi Sheng Hui-Mian Xu Guo-Xin Li Jia-Fu Ji Zhi-Wei Zhou Han Liang Yan-Qiao Zhang Jing Jin Lin Shen Jin Li Rui-Hua Xu 2021Cancer Communications2021,41,8:97
3RNA-seq analysis of prostate cancer in the Chinese population identifies recurrent gene fusions, cancer-associated long noncoding RNAs and aberrant alternative splicings显示文摘在有前列腺癌症的不同赛跑的病人之中有显著不同;然而,位于这差别下面的机制仍然保持不清楚。这里,我们在场 transcriptome 的一处全面风景用 RNA-seq,越过关于基因熔化的前列腺癌症 transcriptomes 的揭示巨大的差异,长 noncoding RNA (长 ncRNA ) ,其他的拼接和体的变化从中国人口 14 主要前列腺癌症和他们的配对的正常对应物介绍。14 个肿瘤(21.4%) 中的三个在中国病人怀有 TMPRSS2 尔格熔化,和这熔化的低流行进一步在一个另外的肿瘤集合(10/54=18.5%) 被证实。尤其是,二新奇基因熔化, CTAGE5-KHDRBS3 (20/54=37%) 和 USP9Y-TTTY15 (19/54=35.2%) ,在我们的耐心的队经常发生了。介绍的进一步系统的 transcriptional 识别了是在肿瘤表示的差别的众多的长 ncRNAs。在长 ncRNA 和基因的表示之间的关联的分析建议长 ncRNAs 可以在 transcriptional 规定以外有功能。这研究在中国人口产出新卓见进前列腺癌症的致病。Shancheng Ren Zhiyu Peng Jian-Hua Mao Yongwei Yu Changjun Yin Xin Gao Zilian Cui Jibin Zhang Kang Yi Weidong Xu Chao Chen Fubo Wang Xinwu Guo Ji Lu Jun Yang Min Wei Zhijian Tian Yinghui Guan Liang Tang Chuanliang Xu Linhui Wang Xu Gao Wei Tian Jian Wang Huanming Yang Jun Wang Yinghao Sun 2012Cell Research2012,22,5:66
4Efficacy and safety of bevacizumab plus chemotherapy in Chinese patients with metastatic colorectal cancer:a randomized phase Ⅲ ARTIST trial显示文摘The efficacy and safety of bevacizumab with modified irinotecan,leucovorin bolus,and 5-fluorouracil intravenous infusion(mIFL) in the first-line treatment of metastatic colorectal cancer(mCRC) has not been well evaluated in randomized clinical trials in Chinese patients.We conducted a phrase Ⅲ trial in which patients with previously untreated mCRC were randomized 2:1 to the mIFL [irinotecan(125 mg/m2),leucovorin(20 mg/m2) bolus,and 5-fluorouracil intravenous infusion(500 mg/m2) weekly for four weeks every six weeks] plus bevacizumab(5 mg/kg every two weeks) group and the mIFL group,respectively.Co-primary objectives were progression-free survival(PFS) and 6-month PFS rate.In total,214 patients were enrolled.Our results showed that addition of bevacizumab to mIFL significantly improved median PFS(4.2 months in the mIFL group vs.8.3 months in the bevacizumab plus mIFL group,P < 0.001),6-month PFS rate(25.0% vs.62.6%,P < 0.001),median overall survival(13.4 months vs.18.7 months,P = 0.014),and response rate(17% vs.35%,P = 0.013).Grades 3 and 4 adverse events included diarrhea(21% in the mIFL group and 26% in the bevacizumab plus mIFL group) and neutropenia(19% in the mIFL group and 33% in the bevacizumab plus mIFL group).No wound-healing complications or congestive heart failure occurred.Our results suggested that bevacizumab plus mIFL is effective and well tolerated as first-line treatment for Chinese patients with mCRC.Clinical benefit and safety profiles were consistent with those observed in pivotal phase Ⅲ trials with mainly Caucasian patients.Zhong-Zhen Guan Jian-Ming Xu Rong-Cheng Luo Feng-Yi Feng Li-Wei Wang Lin Shen Shi-Ying Yu Yi Ba Jun Liang Dong Wang Shu-Kui Qin Jie-Jun Wang Jing He Chuan Qi Rui-Hua Xu 2011Chinese Journal of Cancer2011,30,10:48
5SIRT6 safeguards human mesenchymal stem cells from oxidative stress by coactivating NRF2显示文摘Huize Pan Di Guan Xiaomeng Liu Jingyi Li Lixia Wang Jun Wu Junzhi Zhou Weizhou Zhang Ruotong Ren Weiqi Zhang Ying Li Jiping Yang Ying Hao Tingting Yuan Guohong Yuan Hu Wang Zhenyu Ju Zhiyong Mao Jian Li Jing Qu FuchouTang Guang-Hui Liu 2016Cell Research2016,26,2:32
6Towards developing Mg alloys with simultaneously improved strength and corrosion resistance via RE alloying显示文摘Magnesium(Mg)alloys have received an increasing interest in the past two decades for their tremendous application potential.The strength and corrosion resistance levels of common Mg alloys are still relativity low,and especially they are to be improved simultaneously.The addition of rare earth(RE)to Mg alloys is believed to be beneficial for both the strength and corrosion resistance,and some RE-modified traditional Mg alloys have been studied and some new RE-containing Mg alloys have been developed by now.However,further simultaneous improvements in both strength and anti-corrosion require a better understanding of the behavior and mechanism of RE in Mg alloys.In this review,the common influence mechanisms of RE on mechanical and anti-corrosion properties of Mg alloys are summarized,and the latest research progress of RE-containing Mg alloys with simultaneously improved strength and corrosion resistance are introduced.It is demonstrated that the research on high-strength and high corrosion resistant RE-containing Mg alloys is still immature,and some opinions and suggestions are put forward for the synergetic improvement of the strength and corrosion resistance of Mg alloys,so as to contribute to the further development of Mg alloys with higher performance.Jinshu Xie Jinghuai Zhang Zihao You Shujuan Liu Kai Guan Ruizhi Wu Jun Wang Jing Feng 2021Journal of Magnesium and Alloys2021,9,1:25
7Report on Childhood Obesity in China (9): Sugar-sweetened Beverages Consumption and Obesity显示文摘Objective To explore the associations between sugar-sweetened beverage (SSB) consumption and obesity as well as obesity-related cardiometabolic disorders among children in China. Methods A total of 6974 (boys 3558, girls 3412) children aged 6-13 years participated in the study. Each participant's height, weight, waist circumference, fasting glucose, triglycerides, total cholesterol, high- density lipoprotein cholesterol, and low-density lipoprotein cholesterol were measured. The type of beverage consumption was determined using a self-administered questionnaire. Results SSBs were consumed regularly by 46.1% of the children. The prevalence [adjusted odds ratio (95% confidence internal (CI)] of obesity was 7.6% [as the reference group (ref.)], 10.1% [1.36(1.07, 1.74)], and 11.6% [1.46(1.21, 1.75)], among children who regularly drank milk, other beverages and SSBs, respectively. Regularly drinking SSBs elevated the likelihood of abdominal obesity [adjusted odds ratio (95% CI): 1.36 (1.17, 1.59)]. The prevalence [adjusted odds ratio (95% CI)] of obesity among children who regularly drank sports/caloric beverages, carbonated beverages, sweet tea, and plant protein beverages was 16.8% [2.00(1.31, 3.07)], 12.7% [1.52(1.23, 1.88)], 11.5% [1.52(1.18, 1.95)], and 10.4% [1.41(1.03, 1.94)], respectively, which was higher than that of regular milk drinkers [7.6 % (ref.)]. The prevalence [adjusted odds ratio (95% CI)] of abdominal obesity among children who regularly drank sweet tea, fruit/vegetable juices, and carbonated beverages was 17.7% [1.55(1.26, 1.90)], 16.2% [1.36(1.09, 1.70)], and 15.3% [1.24(1.03, 1.50)], respectively, which was much higher than that of regular milk drinkers [12.8% (ref.)]. Conclusions Regular SSB consumption was positively related to obesity and abdominal obesity. This relationship should be investigated further using a longitudinal study design.SHANG Xian Wen LIU Ai Ling ZHANG Qian HU Xiao Qi DU Song Ming MA Jun XU Gui Fa LI Ying GUO Hong Wei DU Lin LI Ting Yu MA Guan Sheng 2012Biomedical and Environmental Sciences2012,25,2:23
8Expression of regulating apoptosis gene and apoptosis index in primary liver cancer显示文摘INTRODUCTIONProgramed cell death plays an important role in thegenesis of cancer.Certain cancer genes canregulate apoptosis.Recently,several proteins thatare structurally related to Bcl-2,an inhibitor ofapoptosis,have been identified.Therefore,novel strategies and agents that target specificmolecular pathways,as well as triggering aHong Yu Xu You Lin Yang Xi Li Guan Guang Song Ai Min Jiang Li Jun Shi 2000World Journal of Gastroenterology2000,6,5:21
9Safety 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
10Kinetics and corrosion products of aqueous nitrate reduction by iron powder without reaction conditions control显示文摘Although considerable research has been conducted on nitrate reduction by zero-valent iron powder (Fe0), these studies were mostly operated under anaerobic conditions with invariable pH that was unsuitable for practical application. Without reaction conditions (dissolved oxygen or reaction pH) control, this work aimed at subjecting the kinetics of denitrification by microscale Fe0 (160–200 mesh) to analysis the factors affecting the denitrification of nitrate and the composition of iron reductive products coating upon the iron surface. Results of the kinetics study have indicated that a higher initial concentration of nitrate would yield a greater reaction rate constant. The reduction rate of nitrate increased with increasing Fe0 dosage. The reaction can be described as a pseudo-first order reaction with respect to nitrate concentration or Fe0 dosage. Experimental results also suggested that nitrate reduction by microscale Fe0 without reaction condition control primarily was an acid-driven surface-mediated process, and the reaction order was 0.65 with respect to hydrogen ion concentration. The analyses of X-ray diffractometry and X-ray photoelectron spectroscopy indicated that a black coating, consisted of Fe2O3, Fe3O4 and FeO(OH), was formed on the surface of iron grains as an iron corrosion product when the system initial pH was lower than 5. The proportion of FeO(OH) increased as reaction time went on, whereas the proportion of Fe3O4 decreased.FAN Xiaomeng GUAN Xiaohong MA Jun AI Hengyu 2009Journal of Environmental Sciences2009,21,8:17
11Rapid improvement of PM2.5 pollution and associated health benefits in China during 2013–2017显示文摘Exposure to fine particulate matter(PM2.5)is known to harm public health.In China,after implementation of aggressive emissions control measures under the Action Plan of Air Pollution Prevention and Control(2013-2017),air quality has significantly improved.In this work,we investigated changes in PM2.5 exposure and the associated health impacts in China for the period 2013-2017.We used an optimal estimator of PM2.5 combining in-situ observations,satellite measurements,and simulations from a chemical transport model to derive the spatial and temporal variations in PM2.5 exposure,and then used welldeveloped exposure-response functions to estimate the premature deaths attributable to PM2.5 exposure.We found that national population-weighed annual mean PM2.5 concentrations decreased from 67.4μgm-3 in 2013 to 45.5μgm-3 in 2017(32%reduction).This rapid decrease in PM2.5 pollution led to a 14%reduction in premature deaths due to long-term exposure.We estimated that,during 2013-2017,the premature deaths attributable to long-term PM2.5 exposure decreased from 1.2 million(95%CI:1.0,1.3;fraction of total mortality:13%)in 2013 to 1.0 million(95%CI:0.9,1.2;10%)in 2017.Despite the rapid decrease in annual mean PM2.5 concentrations,health benefits associated with reduced long-term exposure were limited,because for many cities,the PM2.5 levels remain at the portion where the exposure-response function is less steeper than that at the lowconcentration end.We also found that the deaths associated with acute exposure decreased by 61%during 2013-2017 due to rapid reduction in the number of heavily polluted days.Our results confirm that clean air policies in China have mitigated the air pollution crisis;however,continuous emissions reduction efforts are required to protect citizens from air pollution.Tao XUE Jun LIU Qiang ZHANG Guannan GENG Yixuan ZHENG Dan TONG Zhu LIU Dabo GUAN Yu BO Tong ZHU Kebin HE Jiming HAO 2019Science China Earth Sciences2019,62,12:17
12Blocking FSH inhibits hepatic cholesterol biosynthesis and reduces serum cholesterol显示文摘Menopause is associated with dyslipidemia and an increased risk of cardio-cerebrovascular disease.The classic view assumes that the underlying mechanism of dyslipidemia is attributed to an insufficiency of estrogen.In addition to a decrease in estrogen, circulating follicle-stimulating hormone (FSH)levels become elevated at menopause.In this study,we find that blocking FSH reduces serum cholesterol via inhibiting hepatic cholesterol biosynthesis.First,epidemiological results show that the serum FSH levels are positively correlated with the serum total cholesterol levels,even after adjustment by considering the effects of serum estrogen,in addition,the prevalence of hypercholesterolemia is significantly higher in peri-menopausal women than that in premenopausal women.Furthermore,we generated a mouse model of FSH elevation by intraperitoneally injecting exogenous FSH into ovariectomized (OVX)mice,in which a normal level of estrogen (E2)was maintained by exogenous supplementation. Consistently,the results indicate that FSH,independent of estrogen,increases the serum cholesterol level in this mouse model. Moreover,blocking FSH signaling by anti-FSHβ antibody or ablating the FSH receptor (FSHR)gene could effectively prevent hypercholesterolemia induced by FSH injection or high-cholesterol diet feeding.Mechanistically,FSH,via binding to hepatic FSHRs, activates the Gi2α/β-arrestin-2/Akt pathway and subsequently inhibits the binding of FoxO1 with the SREBP-2 promoter,thus preventing FoxO1 from repressing SREBP-2 gene transcription.This effect,in turn,results in the upregulation of SREBP-2,which drives HMGCR nascent transcription and de novo cholesterol biosynthesis,leading to the increase of cholesterol accumulation.This study uncovers that blocking FSH signaling might be a new strategy for treating hypercholesterolemia during menopause, particularly for women in peri-menopause characterized by FSH elevation only.Yanjing Guo Meng Zhao Tao Bo Shizhan Ma Zhongshang Yuan Wenbin Chen Zhao He Xu Hou Jun Liu Zhenhai Zhang Qiang Zhu Qiangxiu Wang Xiaoyan Lin Zhongli Yang Min Cui Lu Liu Yujie Li Chunxiao Yu Xiaoyi Qi Qian Wang Haiqing Zhang Qingbo Guan Lifang Zhao Shimeng Xuan Huili Yan Yanliang Lin Li Wang Qihang Li Yongfeng Song Ling Gao Jiajun Zhao 2019Cell Research2019,29,2:16
13Report on Childhood Obesity in China (10): Association of Sleep Duration with Obesity显示文摘Objectives To explore the association of sleep duration with obesity among children in urban areas of China.Methods A total of 6 576 children(3 293 boys and 3 283 girls) aged 7-11 years were randomly selected from 36 primary schools in 6 metropolitan cities in China.A 7-day Physical Activity Recall was used to assess the sleep duration and physical activity level.The height,weight,waist circumference(WC) and percentage of body fat(%BF,as determined by bioelectrical impedance analysis technique) were measured by following the standardized operation procedures.The information on demography,lifestyle and eating habits was collected with a self-administered questionnaire from participants and their parents.Results The average sleep duration per night in the children was 9.7 h with the decreasing trends along with the increase of age(P<0.05).The sleep duration was negatively associated with body mass index(BMI) and WC in both boys and girls after adjustment for confounders(β value-0.23 and-0.82 for boys,-0.24 and-0.91 for girls,respectively,P<0.01).However,no significant association of sleep duration with %BF was found.Children who slept less than 9.0 h per night had a higher risk for overweight and obesity(OR=1.29,95% CI:1.01,1.64) and abdominal obesity(OR=1.38,95% CI:1.04,1.83) as compared with those who slept for 10.0-10.9 h.Conclusions Short sleep duration is associated with obesity.It is important to ensure adequate sleep duration of children and foster their healthy lifestyle at an early stage of life.MENG Li Ping LIUAi Ling HU Xiao Qi ZHANG Qian DU Song Ming FANG Hong Yun MA Jun XU Gui Fa LI Ying GUO Hong Wei DU Lin MA Guan Sheng 2012Biomedical and Environmental Sciences2012,25,2:16
14The immunological roles in acute-on-chronic liver failure:An update显示文摘Background: Acute-on-chronic liver failure (ACLF) refers to the acute deterioration of liver function that occurs in patients with chronic liver disease. ACLF is characterized by acute decompensation, organ failure and high short-term mortality. Numerous studies have been conducted and remarkable progress has been made regarding the pathophysiology and pathogenesis of this disease in the last decade. The present review was to summarize the advances in this field. Data sources: A comprehensive search in PubMed and EMBASE was conducted using the medical subject words “acute-on-chronic liver failure”,“ACLF”,“pathogenesis”,“predictors”, and “immunotherapy” combined with free text terms such as “systemic inflammation” and “immune paralysis”. Relevant papers published before October 31, 2018, were included. Results: ACLF has two marked pathophysiological features, namely, excessive systemic inflammation and susceptibility to infection. The systemic inflammation is mainly manifested by a significant increase in the levels of plasma pro-inflammatory factors, leukocyte count and C-reactive protein. The underlying mechanisms are unclear and may be associated with decreased immune inhibitory cells, abnormal expression of cell surface molecules and intracellular regulatory pathways in immune cells and increased damageassociated molecular patterns in circulation. However, the main cause of susceptibility to infection is immune paralysis. Immunological paralysis is characterized by an attenuated activity of immune cells. The mechanisms are related to elevations of immune inhibitory cells and the concentration of plasma antiinflammatory molecules. Some immune biological indicators, such as soluble CD163, are used to explore the pathogenesis and prognosis of the disease, and some immunotherapies, such as glucocorticoids and granulocyte colony-stimulating factor, are effective on ACLF. Conclusions: Overwhelming systemic inflammation and susceptibility to infection are two key features of ACLF. A better understanding of the state of a patient’s immune system will help to guide immunotherapy for ACLF.Ping Chen Yun-Yun Wang Chao Chen Jun Guan Hai-Hong Zhu Zhi Chen 2019Hepatobiliary & Pancreatic Diseases International2019,18,5:13
15Are humic substances soil microbial residues or unique synthesized compounds?A perspective on their distinctiveness显示文摘Humic substances(HS),which are defined as a series of highly acidic,relatively high-molecular-weight,and yellow to black colored substances formed during the decay and transformation of plant and microbial remains,ubiquitously occur in nature.Humic substances represent the largest stable organic carbon pool in terrestrial environments and are the central characteristic of the soil.However,the validity of the HS concept and the justification of their extraction procedure have been recently debated.Here,we argue that the traditional humic paradigm is still relevant.Humic substances are distinctive and complex because the extracted HS formed during the humification are chemically distinct from their precursors and are heterogeneous among soils.By reviewing the concept,formation pathways,and stabilization of HS,we propose that the key question facing soil scientists is whether HS are soil microbial residues or unique synthesized compounds.Without revealing the distinctiveness of HS,it is impossible to address this question,as the structure,composition,and reactivity of HS are still poorly known owing to the heterogeneity and geographical variability of HS and the limits of the currently available analytical techniques.In our view,the distinctiveness of HS is fundamental to the soil,and thus further studies should be focused on revealing the distinctiveness of HS and explaining why HS hold this distinctiveness.Sen DOU Jun SHAN Xiangyun SONG Rui CAO Meng WU Chenglin LI Song GUAN 2020Pedosphere2020,30,2:12
16Aircraft conflict resolution method based on hybrid ant colony optimization and artificial potential field显示文摘Dear editor, With the significant growth of the civil aviation industry and especially its rapid development in booming economies such as that of China,air traffic flow is drastically increasing,leading to greater congestion around airport terminal areas and in busy airspace [i].The substantial increase in air traffic flow has intensified the risk of violating safe separation regulations,endangering the airspace operational safety.Furthermore,as the result of this significant growth has resulted in problems such as longer delays,which increase fuel consumption and cost the airline industry billions of dollars every year [2,3].Huaxian LIU Feng LIU Xuejun ZHANG Xiangmin GUAN Jun CHEN Pascal SAVINAUD 2018Science China(Information Sciences)2018,61,12:11
17Accuracy of ^18F-FDG PET/CT for lymph node staging in non-small-cell lung cancers显示文摘这回顾的研究评估了的背景2-( F18 )的诊断精确性在在有 non-small-cell 肺癌症( NSCLC )的病人的变形 mediastinal 和 hilar 淋巴节点的外科手术前的诊断的 -fluoro-2-deoxy-D-glucose-positron 排放断层摄影术( 18F-FDG-PET ) /COmputed 断层摄影术( PET/CT ) 39 个病人全部的 .Methods A 收到了外科手术前的 18F-FDG PET/CT 并且手术后的 biopsy.We 在 39 N 把外科手术前的 PET/CT 扫描结果与相应 intraoperative histopathalogicLIU Bao-jun DONG Jing-cheng XU Chang-qing ZUO Chuan-tao LE Jing-jing GUAN Yi-hui ZHAO Jun WU Jin-feng DUAN Xiao-hong CAO Yu-xue 2009Chinese Medical Journal2009,,15:11
18Assessing the numbers of SNPs needed to establish molecular IDs and characterize the genetic diversityof soybean cultivars derived from Tokachi nagaha显示文摘The development of a core set of SNP molecular markers that could be widely used in soybean genetic research would greatly facilitate research into the genetic diversity of soybean.We conducted an analysis of Tokachi nagaha and 137 of its descendant soybean cultivars using 4044 SNP markers with the goal of determining the appropriate number of single-nucleotide polymorphisms(SNPs)needed to construct unambiguous molecular IDs and characterize genetic diversity based on a genetic distance matrix correlation method.When the number of SNPs was held constant,the number of accession pairs that could be distinguished increased as the polymorphism informative content(PIC)value of the SNPs increased.A core panel of 20 selected SNPs from 11 linkage groups with a mean PIC value of 0.3703 and a range of 0.3640–0.3749 was able to identify almost all of the accession pairs in our study[9445 pairs(99.92%)].The eight accession pairs that could not be identified with this core SNP set all originated from the same province and some of them had the same parental cultivars.The molecular IDs of the 138 accessions were constructed using the core 20 SNPs.It is known that both the number of SNPs and PIC values should be considered when SNPs are selected for use in the analysis of genetic diversity.In this study,when the PIC value was 0.3460,the correlation coefficient between the genetic distance matrices associated with a panel of 200 SNPs and the total population was>0.800,indicating satisfactory correlation.Our high-accuracy,high-resolution core SNP panel for germplasm fingerprinting and our findings about assessing genetic diversity will likely markedly improve the management and utilization efficiency of soybean germplasm resources.Zhangxiong Liu Jun Li Xuhong Fan Nang Myint Phyu Sin Htwe Shuming Wang Wen Huang Jiyu Yang Lili Xing Lijun Chen Yinghui Li Rongxia Guan Ruzhen Chang Dechun Wang Lijuan Qiu 2017The Crop Journal2017,5,4:10
19Melittin, the Major Pain-Producing Substance of Bee Venom显示文摘Melittin is a basic 26-amino-acid polypeptide that constitutes 40–60% of dry honeybee(Apis mellifera)venom.Although much is known about its strong surface activity on lipid membranes,less is known about its painproducing effects in the nervous system.In this review,we provide lines of accumulating evidence to support the hypothesis that melittin is the major pain-producing substance of bee venom.At the psychophysical and behavioral levels,subcutaneous injection of melittin causes tonic pain sensation and pain-related behaviors in both humans and animals.At the cellular level,melittin activates primary nociceptor cells through direct and indirect effects.On one hand,melittin can selectively open thermal nociceptor transient receptor potential vanilloid receptor channels via phospholipase A2-lipoxygenase/cyclooxygenase metabolites,leading to depolarization of primary nociceptor cells.On the other hand,algogens and inflammatory/proinflammatory mediators released from the tissue matrix by melittin's pore-forming effects can activate primary nociceptor cells through both ligand-gated receptor channels and the G-protein-coupled receptor-mediated opening of transient receptor potential canonical channels.Moreover,subcutaneous melittin up-regulates Nav1.8 and Nav1.9subunits,resulting in the enhancement of tetrodotoxinresistant Na^+currents and the generation of long-term action potential firing.These nociceptive responses in the periphery finally activate and sensitize the spinal dorsal horn pain-signaling neurons,resulting in spontaneous nociceptive paw flinches and pain hypersensitivity to thermal and mechanical stimuli.Taken together,it is concluded that melittin is the major pain-producing substance of bee venom,by which peripheral persistent pain and hyperalgesia(or allodynia),primary nociceptive neuronal sensitization,and CNS synaptic plasticity(or metaplasticity) can be readily induced and the molecular and cellular mechanisms underlying naturally-occurring venomous biotoxins can be experimentally unraveled.Jun Chen Su-Min Guan Wei Sun Han Fu 2016Neuroscience Bulletin2016,32,3:10
20A controlled study of positron-emission-tomography and positron-emission-tomography/computed tomography in differential diagnosis of solitary pulmonary nodules—report of 60 cases显示文摘The differential diagnosis of solitary pulmonary nodules (SPNs) remains a challenge. It is acknowledged that combining positron-emission tomography (PET) and computed tomography (CT) offers the most reliable noninvasive method for the diagnosis of SPNs. Since Townsend et al1 developed integrated PET/CT in 1999, this technique has increasingly been introduced into clinical practice. To date, nuclear medicine physicians have usually undertaken PET/CT diagnosis, but the question is surfacing as how to make full use of the information of CT image to improve the accuracy of SPN diagnosis. To answer this question, we performed a retrospective study on 60 patients with SPNs. METHODS Patients Between October 2003 and October 2004, 60 consecutive patients with SPNs (age range 26-85 years; median 56 years) underwent PET/CT examination, including 30 with benign and 30 with malignant lesions. Most of the patients had undergone CT scan before PET/CT. None of the patients received chemotherapy or radiation therapy previously.DING Qi-yong HUA Yan-qing ZHANG Guo-zhen ZHAO Jun GUAN Yi-hui GE Xiao-jun MAO Ding-biao ZUO Chuan-tao 2005Chinese Medical Journal2005,,18:10
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