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江苏省优良食味粳稻的遗传与育种研究 被引量:26
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作者 王才林 张亚东 +9 位作者 赵春芳 魏晓东 姚姝 周丽慧 朱镇 陈涛 赵庆勇 赵凌 路凯 梁文化 《遗传》 CAS CSCD 北大核心 2021年第5期442-458,共17页
为了培育适合在江苏种植的优良食味粳稻品种,以优良食味为主攻目标,对江苏省优质、抗病、高产粳稻品种的遗传基础开展了系统研究。通过关联分析,研究稻米蒸煮品质、营养品质与食味品质的关系,明确直链淀粉含量是影响食味品质的关键性状... 为了培育适合在江苏种植的优良食味粳稻品种,以优良食味为主攻目标,对江苏省优质、抗病、高产粳稻品种的遗传基础开展了系统研究。通过关联分析,研究稻米蒸煮品质、营养品质与食味品质的关系,明确直链淀粉含量是影响食味品质的关键性状。直链淀粉含量为10%~14%的半糯米米饭表面光泽透亮、质地柔软、富有弹性,综合了糯米的柔软性和粳米的弹性,冷饭不硬,食味品质极佳,符合长三角地区人们喜食柔软香型粳米的口感需求。筛选出直链淀粉含量在10%左右、含有低直链淀粉含量基因Wx^(mp)的日本半糯粳稻品种“关东194”作为食味品质改良的核心种质。开发Wx^(mp)基因的分子标记,结合利用与抗病、高产相关基因紧密连锁的分子标记,开展优良食味、抗病、高产粳稻聚合育种。育成适合江苏省不同稻区种植的南粳46、南粳5055、南粳9108和南粳5718等优良食味粳稻系列新品种通过审定,形成了覆盖江苏省不同稻区的优良食味粳稻品种布局,累计推广面积超过533万公顷,有力地促进了江苏省及周边地区优质稻米产业的发展,为水稻产业供给侧结构调整,提质增效,保障粮食安全作出了重要贡献。 展开更多
关键词 粳稻 优良食味 品种 遗传 育种
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大亚湾风暴潮波浪传播数学模型 被引量:1
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作者 李大鸣 甄珠 +3 位作者 李彦卿 唐星辰 张弘强 陈硕 《海洋通报》 CAS CSCD 北大核心 2018年第1期45-54,共10页
本文建立了大亚湾风暴潮涌浪传播数学模型,以任意多边形离散计算海区,每一多边形构成单元,以波浪运动学和动力学守恒方程模拟单元内能量传递,以风暴潮过程模拟边界入射波高过程,用风暴潮涌浪传播基本方程和波能缓坡方程结合模拟湾口巨... 本文建立了大亚湾风暴潮涌浪传播数学模型,以任意多边形离散计算海区,每一多边形构成单元,以波浪运动学和动力学守恒方程模拟单元内能量传递,以风暴潮过程模拟边界入射波高过程,用风暴潮涌浪传播基本方程和波能缓坡方程结合模拟湾口巨浪向湾内的传播过程。通过分析大亚湾不同种类岸线反射系数的概率分布,并结合实测波高对模型进行率定,最终确定模型参数。将大亚湾特征点计算波高与统计推荐波高比较进行模型验证,结果显示SE向波高与H_(13%)推荐波高对应较好,可以用于大亚湾海区的波浪预报。计算当大亚湾口分别出现10年一遇、50年一遇及100年一遇的波高时,在E、ESE以及ES向入射波浪条件下大亚湾海域极值波高的分布。分别对风暴潮涌浪在不同类型岸线的爬高以及风暴潮涌浪传播对岸线的作用力进行计算。 展开更多
关键词 风暴潮 数学模型 大亚湾 极值波高 反射系数
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波能测试区波浪运动数学模型研究
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作者 李大鸣 张弘强 +6 位作者 田顺发 欧阳锡钰 李彦卿 唐星辰 陈硕 甄珠 卜世龙 《海洋科学进展》 CAS CSCD 北大核心 2018年第4期512-524,共13页
为研究位于大万山岛南部的波能测试区新增发电机组对该水域波浪场产生的水动力作用,将自主建立的二维Boussinesq波浪模型应用于该测试区,模拟了不同波浪要素下装置布设前线性波的运动传播,装置布设后无锚固时其在波浪中的自由运动、有... 为研究位于大万山岛南部的波能测试区新增发电机组对该水域波浪场产生的水动力作用,将自主建立的二维Boussinesq波浪模型应用于该测试区,模拟了不同波浪要素下装置布设前线性波的运动传播,装置布设后无锚固时其在波浪中的自由运动、有锚固时其对波浪场的影响。结果表明,装置布设前的波浪传播,低潮位时波峰线相较高潮位时更为明显,且受陆域影响更大;装置无锚固时的自由运动,低潮位时其运动速度、旋转角速度均小于高潮位时;装置有锚固时,其对波浪场的影响主要集中在背波面,会形成一道顺波向的"扇形"衰减区,其影响程度随波高、波周期的增大而减小。因此,根据研究结果所得到的相对波高衰减范围,可对后期2,3号发电装置的规划与布设提供科学依据,即尽量避开由1号装置引起的波高衰减区,以免造成波能利用率的降低。 展开更多
关键词 波能测试区 波浪场 数学模型 BOUSSINESQ方程
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内镜下放射状切开术治疗难治性上消化道良性狭窄的临床研究 被引量:3
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作者 王璐 王维钊 +4 位作者 周平红 刘军 朱海杭 朱振 陈磊 《中国内镜杂志》 2021年第9期26-30,共5页
目的探讨内镜下放射状切开术(ERI)治疗难治性上消化道良性狭窄的有效性和安全性。方法回顾性分析2017年11月-2020年1月苏北人民医院因上消化道良性狭窄行ERI治疗的患者14例,记录患者术前狭窄时间、术前接受治疗情况、术前术后吞咽困难... 目的探讨内镜下放射状切开术(ERI)治疗难治性上消化道良性狭窄的有效性和安全性。方法回顾性分析2017年11月-2020年1月苏北人民医院因上消化道良性狭窄行ERI治疗的患者14例,记录患者术前狭窄时间、术前接受治疗情况、术前术后吞咽困难症状、吻合口直径改善情况、术中术后并发症发生情况,并评估其疗效。结果14例患者均完成ERI术,平均操作时间(13.21±4.26)min,切开部位(2.17±0.58)处,所有患者均未出现穿孔和出血等并发症,术前吞咽困难评分为(3.08±0.52)分,术后第2天降至(1.14±0.35)分,术前术后比较,差异有统计学意义(P<0.05),术后3和6个月吞咽困难评分分别为(1.23±0.58)和(1.39±0.66)分,与术后第2天比较,差异无统计学意义(P>0.05),术前、术后当时和术后3个月狭窄处直径分别为(0.28±0.04)、(1.23±0.02)和(1.11±0.03)cm,3个时点比较,差异有统计学意义(P<0.05),术后当时与术后3个月比较,差异无统计学意义(P>0.05)。结论ERI治疗难治性上消化道良性狭窄是安全有效且可行的。 展开更多
关键词 上消化道良性狭窄 吻合口狭窄 内镜下放射状切开 吞咽困难 疗效
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牵伸对聚丙烯腈纤维晶态结构的影响及调控 被引量:3
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作者 朱镇 何州文 +3 位作者 白会涛 陈新 李悦悦 杨长龙 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第10期50-53,共4页
通过不同牵伸工艺制备聚丙烯腈纤维,运用X射线衍射进行表征,研究凝固浴牵伸、水浴牵伸以及沸水牵伸对纤维晶态结构的影响。结果表明,凝固过程是PAN大分子晶态结构成型的重要阶段,该阶段晶核已经基本形成。凝固浴牵伸的增大有利于分子链... 通过不同牵伸工艺制备聚丙烯腈纤维,运用X射线衍射进行表征,研究凝固浴牵伸、水浴牵伸以及沸水牵伸对纤维晶态结构的影响。结果表明,凝固过程是PAN大分子晶态结构成型的重要阶段,该阶段晶核已经基本形成。凝固浴牵伸的增大有利于分子链段由螺旋构象向锯齿构象转变,大分子链段的有序排列,结晶度和晶粒尺寸均有一定程度的提升,但折叠链段的减少不利于大分子成核过程的进行。水浴牵伸及蒸汽牵伸均有助于纤维晶态结构的完善,对分子成核影响不大。通过改变聚丙烯腈原丝制备过程中各流程的牵伸比能够实现对PAN大分子晶态结构的调控。 展开更多
关键词 结晶度 晶粒尺寸 链段排列 成核
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白花九里明提取液对血糖及糖耐量试验的影响 被引量:3
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作者 阳泽世 黄大觉 +3 位作者 幸世勤 黄佳琳 珍珠 王彩冰 《右江医学》 2018年第1期15-18,共4页
目的探讨白花九里明对小鼠血糖浓度及糖耐量试验的影响。方法取KM小鼠60只,按血糖浓度随机分为6组。正常对照组(给予0.9%Na Cl注射液),糖耐量对照组(给予0.9%Na Cl注射液),二甲双胍组(给予盐酸二甲双胍20 mg/ml),白花九里明高、中、低... 目的探讨白花九里明对小鼠血糖浓度及糖耐量试验的影响。方法取KM小鼠60只,按血糖浓度随机分为6组。正常对照组(给予0.9%Na Cl注射液),糖耐量对照组(给予0.9%Na Cl注射液),二甲双胍组(给予盐酸二甲双胍20 mg/ml),白花九里明高、中、低浓度组(分别给予1.0、0.5、0.25 g/ml的白花九里明提取液),每天灌胃1次(灌胃量按鼠重10 ml/kg计算)共15 d。末次灌胃后30 min检测各组小鼠血糖浓度紧接着进行糖耐量试验,除正常对照组小鼠给予0.9%Na Cl注射液灌胃外,其余各组小鼠给予葡萄糖注射液0.25 g/ml灌胃(灌胃量按鼠重10 ml/kg计算),检测30 min、60 min的血糖浓度。结果糖耐量试验对照组、白花九里明低浓度组的血糖浓度与正常对照组比较无统计学意义(P>0.05),二甲双胍组的血糖浓度明显低于正常对照组(P<0.05),白花九里明中浓度组和高浓度组的血糖浓度明显高于正常对照组和白花九里明低浓度组(P<0.05),白花九里明中浓度组与高浓度组的血糖浓度比较无统计学意义(P>0.05)。糖耐量试验30 min:糖耐量试验对照组的血糖浓度明显高于正常对照组(P<0.05),除正常对照组外,其余各组血糖浓度均明显高于糖耐量试验前(P<0.05或0.01)。糖耐量试验60 min:各组血糖浓度与糖耐量试验前比较均无统计学意义(P>0.05)。结论白花九里明用量高达一定浓度时可升高血糖,但不影响机体的糖耐量。 展开更多
关键词 白花九里明 血糖浓度 糖耐量试验 小鼠
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Molecular Epidemiological Analysis of Echovirus 19 Isolated From an Outbreak Associated With Hand, Foot, and Mouth Disease (HFMD) in Shandong Province of China 被引量:22
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作者 zhen zhu WEN-BO XU +6 位作者 AI-QIANG XU HAI-YAN WANG YONG ZHANG LI-ZHI SONG Hui-LiYANG YANLI FENGJI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第4期321-328,共8页
To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 (El9) isolates collected from an outbreak associated with hand, foot and mouth disease (HFMD) in Tai'an city of Sha... To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 (El9) isolates collected from an outbreak associated with hand, foot and mouth disease (HFMD) in Tai'an city of Shandong Province of China from July to September, 2003. Methods Thirty seven Echovirus 19 isolates were isolated from stool specimens and throat swabs collected during the outbreak, then major capsid (VP1) genomic sequence was determined, and phylogenetic tree was done based on the VP1 sequences among these 37 and other El9 viruses deposited in the Genbank. Also a representative strain named CHN-SD03-TN12 was selected for sequencing of 5′-untranslated regions (5′-UTR). Results The identity rate was about 98.9%-100% among all these 37 El9 viruses. The genetic relationships between these 37 El9 isolates and other strains reported were also depicted. The identity rate was about 78.4%-78.9% compared with El9 reference strain Burke. The substitutions in the sequence of 5′-UTR resulted in changes in the conjectural properties of 5′-UTR of El9 viruses. Condusion The genetic features of El9 viruses isolated during the outbreak in Shandong Province in 2003 may be associated with a genetic and antigenic drift that changes the virulence of the Shandong isolates, but the molecular changes in Shandong El9 viruses contributing to their phenotype remain to be further illuminated. However, the sequences described in this paper substantiate the changes taken place in capsid VPI and 5′UTR regions. These substitutions may contribute to their tropism and virulence, and play a significant role in pathogenesis and clinical manifestations of the disease. 展开更多
关键词 Enterovirus 19(E19) Hand foot and mouth disease (HFMD) Molecular epidemiology 5′ Untranslated regions(5′-UTR) B-C loop
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Interleukin-18 genetic polymorphisms contribute differentially to the susceptibility to Crohn's disease 被引量:6
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作者 Su-Jun Gao Li Zhang +4 位作者 Wei Lu Lu Wang Lei Chen zhen zhu Hai-Hang zhu 《World Journal of Gastroenterology》 SCIE CAS 2015年第28期8711-8722,共12页
AIM:To investigate the correlation between interleukin-18(IL-18) gene polymorphisms and the risk of developing Crohn's disease(CD).METHODS:The PubMed,CISCOM,CINAHL,Web of Science,EBSCO,Cochrane Library,MEDLINE,EMB... AIM:To investigate the correlation between interleukin-18(IL-18) gene polymorphisms and the risk of developing Crohn's disease(CD).METHODS:The PubMed,CISCOM,CINAHL,Web of Science,EBSCO,Cochrane Library,MEDLINE,EMBASE and CBM databases were searched without any language restrictions using combinations of keywords relating to CD and IL-18 for relevant articles published before November 1st,2013.Screening of the published studies retrieved from searches was based on our stringent inclusion and exclusion criteria and resulted in seven eligible studies for meta-analysis.A metaanalysis was conducted using a random-effects model with STATA 12.0 software.Crude odds ratios(ORs) with95%confidence intervals(95%CI) were calculated.RESULTS:Seven case-control studies,with a total of1930 CD cases and 1930 healthy subjects,met our inclusion criteria.The results of our meta-analysis indicated that the IL-18 rs1946518 A>C and rs187238G>C polymorphisms may correlate with an increased risk of CD under five genetic models(all P < 0.05).Furthermore,we observed positive associations between the IL-18 rs360718 A>C polymorphism and CD risk under three genetic models(C allele vs A allele:OR = 2.03,95%CI:1.20-3.43,P = 0.008;CC vs AA+AC:OR = 2.39,95%CI:1.2-4.43,P = 0.006;CC vs AC:OR = 2.31,95%CI:1.22-4.38,P = 0.010).However,such associations were not found for the IL-18 rs917997 C>T,codon 35 A>C and rs1946519G>T polymorphisms(all P> 0.05).A subgroup analysis was conducted to investigate the effect of ethnicity on an individual's susceptibility to CD.Our results revealed positive correlations between IL-18 genetic polymorphisms and an increased risk of CD among Asians and Africans(all P < 0.05),but not among Caucasians(all P> 0.05).CONCLUSION:This meta-analysis indicated that the IL-18 rs1946518 A> C,rs187238 G>C and rs360718A>C polymorphisms may contribute to susceptibility to CD,especially among Asians and Africans.These polymorphisms are known to reduce IL-18 mRNA and protein levels. 展开更多
关键词 INTERLEUKIN-18 Single NUCLEOTIDE polymorphism Crohn's disease Meta-analysis
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社会实践在大学生角色社会化中的功能分析 被引量:8
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作者 郭彤梅 杨婕筠 +3 位作者 甄珠 刘彦华 丁善芹 侯绍江 《教育理论与实践》 北大核心 2019年第27期38-41,共4页
大学生社会实践活动作为学校教育的延伸和补充,是实现大学生角色社会化的重要途径。为探究志愿服务、兼职和实习三类社会实践在大学生角色社会化中的功能效应,通过问卷调查从太原工业学院各年级学生中获取数据,利用结构方程模型(SEM)进... 大学生社会实践活动作为学校教育的延伸和补充,是实现大学生角色社会化的重要途径。为探究志愿服务、兼职和实习三类社会实践在大学生角色社会化中的功能效应,通过问卷调查从太原工业学院各年级学生中获取数据,利用结构方程模型(SEM)进行模型拟合,采用变量权重分析各因素的影响度。研究结果表明:参加志愿服务对大学生角色社会化的进程作用较明显,社会实践的功能也更有体现。 展开更多
关键词 社会实践 大学生角色社会化 转化能力 社交能力 适应能力
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Preparation of Monoclonal Antibody Against HPT and Its Application to Detecting Marker Protein in Genetically Modified Rice 被引量:3
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作者 LI-CHEN YANG SU-XIANG ZHANG +3 位作者 GUO-HUA PI YING-HUA LI zhen zhu XIAO-GUANG YANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第5期321-325,共5页
To produce the monoclonal antibodies (mAbs) against hygromycin B phosphotransferase (HPT) and to develop immunoassay based on mAbs for biosafety assessment of HPT in genetically modified rice (GM rice). Methods ... To produce the monoclonal antibodies (mAbs) against hygromycin B phosphotransferase (HPT) and to develop immunoassay based on mAbs for biosafety assessment of HPT in genetically modified rice (GM rice). Methods BALB/c mice were immunized with purified recombinant 6His. HPT protein, and the conventional hybridoma technology was used to generate the monoclonal hybridoma cells. ELISA and Western blot were used to analyze the specificity of mAbs recognizing HPT and the cross reaction with other proteins. A double-Ab sandwich ELISA method was established to detect HPT expression level in the sck gene-modified rice plants. Results Four hybridomas, named F1,D4-2, D4-4, and D4-5, producing the mAbs against HPT were successfully obtained with the titer of ascetic mAbs ranging from 10×10^-4 to10×10^-5. Identification of subclass showed that all the produced mAbs belonged to IgG1. Western blot showed specific binding reaction between the mAbs to the HPT proteins expressed in the GM rice. A double sandwich ELISA coated with anti-HPT polyclonal antibody was established with mAbs as sandwich antibody, which showed a sensitivity of 30ng/mL and did not crossreact with other proteins. The expression level of HPT in the leaves of sck-transformed lines was detected (80-150ng/mL). But HPT protein in the grain and seed of GM rice could not be detected using this ELISA assay, Conclusion Anti-HPT mAbs prepared herein have a high specificity and can be used for rapid assay of HPT antigen. The expression level of HPT in the GM rice grain and seed is lower than our ELISA detection limit. 展开更多
关键词 HPT Monoclonal antibody PREPARATION APPLICATION
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Expression of huCdc7 in colorectal cancer 被引量:2
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作者 Hai-Jun Chen zhen zhu +7 位作者 Xue-Lin Wang Quan-Lin Feng Qing Wu zheng-Ping Xu Jiang Wu Xiao-Feng Yu Hong-Liang Qian Qi Lu 《World Journal of Gastroenterology》 SCIE CAS 2013年第20期3130-3133,共4页
AIM:To detect the expression of huCdc7 in colorectal cancer.METHODS:The mRNA and protein expression of huCdc7 in 39 colorectal cancer tissue specimens and matched tumor-adjacent normal colorectal tissue specimens was ... AIM:To detect the expression of huCdc7 in colorectal cancer.METHODS:The mRNA and protein expression of huCdc7 in 39 colorectal cancer tissue specimens and matched tumor-adjacent normal colorectal tissue specimens was detected by reverse transcription-polymerase chain reaction and immunohistochemistry,respectively.RESULTS:The relative expression level of huCdc7 mRNA in colorectal cancer was significantly higher than that in tumor-adjacent normal colorectal tissues(0.03675 ± 1.00 vs 0.01199 ± 0.44,P < 0.05).huCdc7-positive cells displayed brown granules in the nucleus.Tumor tissues contained many huCdc7-positive cells,whereas normal colorectal tissues contained very few positive cells.CONCLUSION:huCdc7 may play an important role in the development and progression of colorectal cancer. 展开更多
关键词 huCdc7 Semiquantitative REVERSE transcription-polymerase CHAIN reaction COLORECTAL cancer
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Elevated Plasma Tissue-type Plasminogen Activator (t-PA) and Soluble Throm-bomodulin in Patients Suffering From Severe Acute Respiratory Syndrome (SARS) as a Possible Index for Prognosis and Treatment Strategy 被引量:2
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作者 ZHONG-HUA LIU RAN WEI +13 位作者 YA-PING WU TON LISMAN ZENG-XIAN WANG JI-JU HAN DAO-LING REN BIN CHEN ZUO-LI XIA BIAO CHEN zhen zhu YAN ZHANG XING CUI HAI-TAO HU PHILIP G. DE GROOT WEN-BO XU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第4期260-264,共5页
To detect the presence of endothelial injury in patients with severe acute respiratory syndrome (SARS) via enhanced levels of tissue-type plasminogen activator (t-PA) and soluble thrombomodulin (sTM). Methods Ca... To detect the presence of endothelial injury in patients with severe acute respiratory syndrome (SARS) via enhanced levels of tissue-type plasminogen activator (t-PA) and soluble thrombomodulin (sTM). Methods Case patients were from Xuanwu Hospital (Capital University of Medical Sciences, Beijing, China), and all of them met clinical criteria for SARS. Healthy controls were some of the hospital employees. Endothelial injury bio-markers tPA and sTM were detected by commercial ELISA-methods. Results Classic plasma markers of endothelial injury, tPA and sTM significantly elevated in SARS patients in comparison to controls [t-PA: 1.48±0.16 nmol/L versus 0.25±0.03 nmol/L (P〈0.0001), and sTM: 0.26±0.06 nmol/L versus 0.14±0.02 nmol/L (P〈0.05)]. The only patient who died had extremely high levels of these endothelial injury markers (t-PA: 2.77 nmol/L and sTM: 1.01 nmol/L). The likelihood ratio analysis indicated the excellent discriminating power for SARS at the optimal cut-point of 0.49 nmol/L for tPA and 0.20 nmol/L for sTM, respectively. Significant numerical correlations were found among these endothelial injury markers in SARS patients. The numerical coefficient of correlation Pearson r between t-PA and sTM was 0.5867 (P〈0.05). Conclusion Increased plasma concentrations of tPA and sTM in patients with SARS suggest the possibility of endothelial injury. SARS patients might need anticoagulant therapy or fibrinolytic therapy in order to reverse intraalveolar coagulation, microthrombi formation, alveolar and interstitial fibrin deposition. It may not only provide a useful treatment and prognostic index but also allow a further understanding of the pathological condition of the disease. 展开更多
关键词 Severe acute respiratory syndrome (SARS) Tissue-type plasminogen activator (t-PA) Soluble thrombomodulin(sTM) SARS-CORONAVIRUS Bio-markers Endothelial injury
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Fundamental band gap and alignment of two-dimensional semiconductors explored by machine learning 被引量:2
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作者 朱震 董宝娟 +2 位作者 郭怀红 杨腾 张志东 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期327-335,共9页
Two-dimensional(2D)semiconductors isoelectronic to phosphorene have been drawing much attention recently due to their promising applications for next-generation(opt)electronics.This family of 2D materials contains mor... Two-dimensional(2D)semiconductors isoelectronic to phosphorene have been drawing much attention recently due to their promising applications for next-generation(opt)electronics.This family of 2D materials contains more than 400members,including(a)elemental group-V materials,(b)binary III–VII and IV–VI compounds,(c)ternary III–VI–VII and IV–V–VII compounds,making materials design with targeted functionality unprecedentedly rich and extremely challenging.To shed light on rational functionality design with this family of materials,we systemically explore their fundamental band gaps and alignments using hybrid density functional theory(DFT)in combination with machine learning.First,calculations are performed using both the Perdew–Burke–Ernzerhof exchange–correlation functional within the generalgradient-density approximation(GGA-PBE)and Heyd–Scuseria–Ernzerhof hybrid functional(HSE)as a reference.We find this family of materials share similar crystalline structures,but possess largely distributed band-gap values ranging approximately from 0 eV to 8 eV.Then,we apply machine learning methods,including linear regression(LR),random forest regression(RFR),and support vector machine regression(SVR),to build models for the prediction of electronic properties.Among these models,SVR is found to have the best performance,yielding the root mean square error(RMSE)less than 0.15 eV for the predicted band gaps,valence-band maximums(VBMs),and conduction-band minimums(CBMs)when both PBE results and elemental information are used as features.Thus,we demonstrate that the machine learning models are universally suitable for screening 2D isoelectronic systems with targeted functionality,and especially valuable for the design of alloys and heterogeneous systems. 展开更多
关键词 TWO-DIMENSIONAL SEMICONDUCTORS machine learning
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Scanning tunneling microscopic investigation on morphology of magnetic Weyl semimetal YbMnBi2 被引量:1
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作者 朱朕 严冬 +10 位作者 聂晓昂 徐豪科 杨旭 管丹丹 王世勇 李耀义 刘灿华 刘军伟 罗惠霞 郑浩 贾金锋 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期87-90,共4页
YbMnBi2 is a recently discovered time-reversal-symmetry breaking type-Ⅱ Weyl semimetal.However, as a representation of the new category of topological matters, the scanning tunneling microcopy(STM) results on such im... YbMnBi2 is a recently discovered time-reversal-symmetry breaking type-Ⅱ Weyl semimetal.However, as a representation of the new category of topological matters, the scanning tunneling microcopy(STM) results on such important material are still absent.Here, we report the STM investigations on the morphology of vacuum cleaved single crystalline YbMnBi2 samples.A hill and valley type of topography is observed on the YbMnBi2 surface, which is consistent with the non-layer nature of its crystal structure.Analysis of STM images yields the information of the index of the vicinal surface.Our results here lay a playground of future atomic scale research on YbMnBi2. 展开更多
关键词 WEYL SEMIMETAL topological INSULATOR SCANNING TUNNELING microscopy
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Experimental study of relationship between average isotopic fractionation factor and evaporation rate 被引量:1
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作者 Tao WANG Wei-min BAO +6 位作者 Hai-li XU zhen zhu Si-min QU Peng SHI Hai-ying HU Rui-qi FAN Qian LI 《Water Science and Engineering》 EI CAS 2010年第4期394-404,共11页
Isotopic fractionation is the basis of tracing the water cycle using hydrogen and oxygen isotopes. Isotopic fractionation factors in water evaporating from free water bodies are mainly affected by temperature and rela... Isotopic fractionation is the basis of tracing the water cycle using hydrogen and oxygen isotopes. Isotopic fractionation factors in water evaporating from free water bodies are mainly affected by temperature and relative humidity, and vary significantly with these atmospheric factors over the course of a day. The evaporation rate (E) can reveal the effects of atmospheric factors. Therefore, there should be a certain functional relationship between isotopic fractionation factors and E. An average isotopic fractionation factor ( t~* ) was defined to describe isotopic differences between vapor and liquid phases in evaporation with time intervals of days. The relationship between or* and E based on the isotopic mass balance was investigated through an evaporation pan experiment with no inflow. The experimental results showed that the isotopic compositions of residual water were more enriched with time; tr* was affected by air temperature, relative humidity, and other atmospheric factors, and had a strong functional relation with E. The values of 0~* can be easily calculated with the known values of E, the initial volume of water in the pan, and isotopic compositions of residual water. 展开更多
关键词 average isotopic fractionation factor evaporation rate hydrogen and oxygen isotopes
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上海某猪场配怀母猪脱肛治疗方案比较及其预防
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作者 朱镇 张振玲 《猪业科学》 2020年第10期138-141,共4页
文章对上海某猪场配怀母猪脱肛的三种治疗方案进行对比,结果发现:手术缝合治疗母猪脱肛实际疗效最为理想,可作为猪场治疗母猪脱肛的主要手段;热灼法虽然操作简单,但可能对脱肛严重的猪不起作用,所以脱肛严重时不建议使用,或用在猪脱肛... 文章对上海某猪场配怀母猪脱肛的三种治疗方案进行对比,结果发现:手术缝合治疗母猪脱肛实际疗效最为理想,可作为猪场治疗母猪脱肛的主要手段;热灼法虽然操作简单,但可能对脱肛严重的猪不起作用,所以脱肛严重时不建议使用,或用在猪脱肛后的手术护理上;固涩液治疗法疗效有限,不如手术缝合法那样可使直肠长久复回原位,因而也不推荐猪场使用。最后,文章综合3种方案的实际效果对猪场提出了预防母猪脱肛的建议。 展开更多
关键词 脱肛 手术缝合法 热灼法 固涩液治疗法 预防
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Tailoring electronic properties of two-dimensional antimonene with isoelectronic counterparts
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作者 张也 郭怀红 +4 位作者 董宝娟 朱震 杨腾 王吉章 张志东 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期41-49,共9页
Using ab initio density functional theory calculations, we explore the three most stable structural phases, namely, α,β, and cubic(c) phases, of two-dimensional(2D) antimonene, as well as its isoelectronic counterpa... Using ab initio density functional theory calculations, we explore the three most stable structural phases, namely, α,β, and cubic(c) phases, of two-dimensional(2D) antimonene, as well as its isoelectronic counterparts SnTe and InI. We find that the band gap increases monotonically from Sb to SnTe to InI along with an increase in ionicity, independent of the structural phases. The band gaps of this material family cover the entire visible-light energy spectrum, ranging from 0.26 eV to 3.37 eV, rendering them promising candidates for optoelectronic applications. Meanwhile, band-edge positions of these materials are explored and all three types of band alignments can be achieved through properly combining antimonene with its isoelectronic counterparts to form heterostructures. The richness in electronic properties for this isoelectronic material family sheds light on possibilities to tailor the fundamental band gap of antimonene via lateral alloying or forming vertical heterostructures. 展开更多
关键词 TAILORING ELECTRONIC PROPERTIES TWO-DIMENSIONAL antimonene isoelectronic COUNTERPARTS
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Purification and Immunity Analysis of Recombinant 6His-HPT Protein Expressed in E.coli 被引量:1
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作者 LI-CHEN YANG zhen zhu XIAO-GUANG YANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第2期149-156,共8页
To obtain HPT protein (Hygromycin B Phosphotransferase), a kind of plant selective maker gene product expressed from E.coli and to prepare the polyclonal antibody (pAbs) against it. Methods HPT cDNA fragment was ob... To obtain HPT protein (Hygromycin B Phosphotransferase), a kind of plant selective maker gene product expressed from E.coli and to prepare the polyclonal antibody (pAbs) against it. Methods HPT cDNA fragment was obtained by PCR and was inserted into the prokaryotic expressing vector pBV222. Then the constructed recombinant plasmid pBV222-HPT was transfered into E.coli DH5?for HPT expression. The recombinant expressing system was confirmed by restriction endonuclease digestion, DNA sequencing and protein expression. E.coli cells were lysed by sonication and detergent dissolution. After cell membrane was extracted, the inclusion bodies were denatured by 8 mol/L Urea and purified with metal chelate affinity chromatography on Ni-NTA agarose under denaturing condition. The purified 6His-HPT was characterized by SDS-PAGE, and used to immunize rabbit. The titer and specificity of antisera were detected by ELISA and Western blot respecitively. Results Analysis of DNA sequence and restricted enzymes showed that the sequence of PBV222-HPT plasmid was correct. The amount of recombinant HPT expressed in E.coli accounted for 30% of total cellular proteins. From 1 liter of fermentative bacteria about 22 milligrams of pure recombinant HPT was isolated with purity above 95%. The recombinant HPT protein could produce high titer antiserum in rabbits and show good immunity activity. Western blot showed specific binding reaction between the antiserum to the purified 6His-HPT protein and their expressed products (plants protein and bacterial protein). Conclusion HPT protein can be expressed and purified from E.coli by a relatively simple method, which has high immunity activity. 展开更多
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Metastable Face-Centered Cubic Structure and Structural Transition of Sn on 2H-NbSe2(0001)
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作者 李爱民 董璐 +8 位作者 杨心怡 朱朕 王观勇 管丹丹 郑浩 李耀义 刘灿华 钱冬 贾金锋 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第6期58-61,共4页
Surface structures and properties of Sn islands grown on superconducting substrate 2H-NbSe2(0001)are studied using low temperature scanning tunneling microscopy or spectroscopy.The pure face-centered cubic(fee)str... Surface structures and properties of Sn islands grown on superconducting substrate 2H-NbSe2(0001)are studied using low temperature scanning tunneling microscopy or spectroscopy.The pure face-centered cubic(fee)structure of Sn surface is obtained.Superconductivity is also detected on the fcc-Sn(111)surface,and the size of superconducting gap on the Sn surface is nearly the same as that on the superconducting substrate.Furthermore,phase transition occurs from fcc-Sn(111)toβ-Sn(001)by keeping the sample at room temperature for a certain time.Due to the strain relaxation on theβ-Sn islands,both the in-plane unit cell and out-of-plane structures distort,and the height of surface atoms varies periodically to form a universal ripple structure. 展开更多
关键词 SN Metastable Face-Centered Cubic Structure and Structural Transition of Sn on 2H-NbSe2
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Epidemiological Characteristics of Human Parainfluenza Viruses Infections-China,2019-2023
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作者 Yixuan Gao Yingwei Ma +15 位作者 Daxing Feng Feng Zhang Biao Wang Xiaoqing Liu Bing zhu Hui Xie Linqing Zhao Xiaoru Long Ying Chen Bing Wang Jie Jiang zhen zhu Yan Zhang Aili Cui Baicheng Xia Naiying Mao 《China CDC weekly》 SCIE CSCD 2024年第12期235-241,I0003,I0004,共9页
Introduction:A retrospective study based on sentinel surveillance was conducted in 10 provinciallevel administrative divisions(PLADs)in China to enhance the understanding of the epidemiological characteristics of huma... Introduction:A retrospective study based on sentinel surveillance was conducted in 10 provinciallevel administrative divisions(PLADs)in China to enhance the understanding of the epidemiological characteristics of human parainfluenza viruses(HPIVs).Methods:From January 2019 to June 2023,respiratory specimens were collected from individuals with acute respiratory infections(ARIs)and screened for four HPIVs serotypes and other common respiratory viruses using multiplex real-time polymerase chain reaction(PCR).This study analyzed the association of HPIVs infections with seasonal patterns,geographical distribution,demographic profiles,clinical features,and co-infection status.Results:During the study period,a total of 12,866 ARIs were included.The overall detection rate of HPIVs was 6.15%,varying from 5.04%in 2022 to 9.70%in 2020.The median age of HPIVs-infected patients was 3 years.HPIV2 was more prevalent among individuals aged 5–17 years(42.57%),while HPIV4 was more common in those over 65 years(12.24%).HPIV3(54.16%)and HPIV1(27.18%)were the predominant serotypes,and their prevalence exhibited significant seasonal fluctuations postcoronavirus disease 2019(COVID-19)pandemic.The peak of HPIV3 shifted three months later in 2020 compared to 2019 and returned to a summer peak thereafter.Two peaks of HPIV1 were observed in 2021 following the peak of HPIV3.Additionally,coinfections were frequent in HPIVs cases(overall rate:22.12%),with human rhinovirus being the most common co-infecting virus.Conclusions:The prevalence of HPIVs in China was predominantly due to HPIV3 and HPIV1,and their seasonal patterns were altered by pandemic restrictions.Hence,continuous surveillance of HPIVs is essential. 展开更多
关键词 PREVALENCE SEASONAL HUMAN
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