检索结果-南通市图书馆

Association between body mass index and in vitro fertilization/intra-cytoplasmic sperm injection outcomes:An analysis of 15,124 normal ovarian responders in China

引用

Chinese Medical Journal 2024年第7期137卷 837-845页

作者： Danlei Zheng Yuanyuan Wang lixue chen Lin Zeng Rong Li Department of Obstetrics and Gynecology Center for Reproductive MedicinePeking University Third HospitalBeijing 100191China Research Center of Clinical Epidemiology Peking University Third HospitalBeijing 100191China

Background:High body mass index(BMI)results in decreased fecundity,and women with high BMI have reduced rates of clinical pregnancy and live birth in in vitro fertilization/intra-cytoplasmic sperm injection(IVF/ICSI).Meanwhile,ovarian responses show great heterogeneity in patients with a high *** study aimed to analyze the effects of a high BMI on IVF/ICSI outcomes in the Chinese female with normal ovarian ***:We performed a retrospective cohort study comprising 15,124 patients from the medical record system of the Reproductive Center of Peking University Third Hospital,with 3530(23.3%)in the overweight group and 1380(9.1%)in the obese group,who had a normal ovarian response(5-15 oocytes retrieved)and underwent fresh embryo transfer(ET)cycles from January 2017 to December 2018,followed by linked frozen-thawed embryo transfer(FET)cycles from January 2017 to December *** live birth rate(CLBR)was used as the primary ***,a generalized additive model was applied to visually illustrate the curvilinear relationship between BMI and the *** used a decision tree to identify the specific population where high BMI had the greatest effect on IVF/ICSI ***:High BMI was associated with poor IVF/ICSI outcomes,both in cumulative cycles and in separate fresh ET or FET *** cumulative cycles,compared with the normal weight group,obesity was correlated with a lower positive pregnancy test rate(adjusted odds ratio[aOR]:0.809,95%confidence interval[CI]:0.682-0.960),lower clinical pregnancy rate(aOR:0.766,95%CI:0.646-0.907),lower live birth rate(aOR:0.706,95%CI:0.595-0.838),higher cesarean section rate(aOR:2.066,95%CI:1.533-2.785),and higher rate of large for gestational age(aOR:2.273,95%CI:1.547-3.341).In the generalized additive model,we found that CLBR declined with increasing BMI,with 24 kg/m^(2)as an inflection *** the decision tree,BMI only made a difference in the population aged≤34.5 years,with anti-Muller

关键词： Obesity Body mass index fertilization Live birth Decision trees Normal ovarian response

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Associations between thyroid function and autoimmunity indicators and in vitro fertilization/intracytoplasmic sperm injection outcomes in euthyroid PCOS women

引用

中华医学杂志(英文版) 2024年第16期137卷 2005-2007页

作者： Jiang Huahua chen lixue Huang Ning Shi Huifeng Chi Hongbin Yang Rui Long Xiaoyu Qiao Jie Department of Obstetrics and Gynecology Center for Reproductive Medicine Peking University Third Hospital Beijing China National Clinical Research Center for Obstetrics and Gynecology Peking University Third Hospital Beijing China Key Laboratory of Assisted Reproduction Peking University Ministry of Education Beijing China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing China Department of Obstetrics and Gynecology Peking University Third Hospital Beijing China National Centre for Healthcare Quality Management in Obstetrics Beijing China Beijing Advanced Innovation Center for Genomics Peking University Beijing China Peking-Tsinghua Center for Life Sciences Peking University Beijing China

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

电流频率对真空断路器开断能力影响的仿真分析

引用

高压电器 2024年第10期60卷 104-109页

作者：丁璨李凯明袁召陈立学三峡大学电气与新能源学院湖北宜昌443002 三峡大学湖北省输电线路工程技术研究中心湖北宜昌443002 华中科技大学电气与电子工程学院强电磁工程与新技术国家重点实验室武汉430074

随着风电等新能源以及直流电网的发展,断路器开断电流的频率呈现出多样化,要求断路器可以开断高于或者低于50 Hz的电流。针对此问题,文中试图从燃弧过程、磁场调控以及弧后过程3个方面去研究电流频率对真空断路器开断能力的影响。文中... 详细信息

随着风电等新能源以及直流电网的发展,断路器开断电流的频率呈现出多样化,要求断路器可以开断高于或者低于50 Hz的电流。针对此问题,文中试图从燃弧过程、磁场调控以及弧后过程3个方面去研究电流频率对真空断路器开断能力的影响。文中首先研究了不同频率下的电弧微观参数分布,发现随着频率的增加,电弧形态越呈现出集聚的现象,触头呈现出局部烧蚀严重的现象,但是由于燃弧时间变短,触头总的烧蚀变小。频率越低,燃弧时间越长,触头则呈现出严重的烧蚀。然后研究了不同频率下常用杯状纵磁触头的磁场分布,发现随着频率的增加,磁场分布越不均匀,对电弧等离子体的扩散作用变小,并且由于燃弧时间的缩短,等离子体更不易扩散。最后通过频率对弧后鞘层生长过程的影响分析发现,频率越大,弧后鞘层生长到满开距越慢,从而降低开断能力。文中得出:低频下的断路器触头整体烧蚀严重,电弧熄弧的时候将产生大量的金属蒸气,金属蒸气的衰减过程将主导断路器的弧后绝缘恢复过程,而高频下的断路器的弧后绝缘恢复过程则由鞘层生长过程主导。

关键词：电流频率真空电弧触头烧蚀磁场分布弧后过程

来源：

维普期刊数据库

同方期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

滑动电接触梯度功能材料电枢熔化磨损特性仿真研究

引用

电工技术学报 2024年第19期39卷 5947-5957页

作者：邹昕阳陈立学王增基许璇张智榣强电磁技术全国重点实验室(华中科技大学) 武汉430074 脉冲功率技术教育部重点实验室(华中科技大学电气与电子工程学院) 武汉430074

该文提出一种利用梯度功能材料电枢提高电枢表面熔点、降低电枢熔化磨损率,从而延长电磁轨道发射器中轨道使用寿命的方法,并通过多物理场耦合仿真选择合适的电枢梯度功能材料,研究梯度功能材料电枢的熔化磨损特性。在COMSOL Multiphysic... 详细信息

该文提出一种利用梯度功能材料电枢提高电枢表面熔点、降低电枢熔化磨损率,从而延长电磁轨道发射器中轨道使用寿命的方法,并通过多物理场耦合仿真选择合适的电枢梯度功能材料,研究梯度功能材料电枢的熔化磨损特性。在COMSOL Multiphysics仿真软件中采用“平板式”分层的梯度功能材料模型,将各层复合材料的物理性能表示为关于功能体材料体积分数的函数,模拟在电流流经结构体电阻以及电枢-轨道表面接触电阻产生的焦耳热影响下,电枢于初始阶段的熔化情况。结果表明,铬更适合作为功能体材料加入铝基体形成梯度功能材料电枢,铌、钼次之,而铜功能体梯度功能材料电枢的抗熔化磨损能力较弱。该文仿真实验和结果对梯度功能材料电枢的研发和试验具有一定的指导意义。

关键词：电磁轨道炮梯度功能材料电枢熔化磨损仿真分析

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

职业教育学分银行建设的价值、困境与对策

引用

九江职业技术学院学报 2024年第3期 23-27页

作者：陈立雪邢世凯王颖河北师范大学河北石家庄050024 唐山海运职业学院河北唐山063200

职业教育学分银行作为一种教育管理制度,其核心目的在于推进学习成果的认定、累计与互换,进而为学习者在学习路径上提供更为灵活和便捷的选择。当前,我国学分银行建设和实施过程中,面临着社会的需求尚待提升、职业教育学分银行架构体系... 详细信息

职业教育学分银行作为一种教育管理制度,其核心目的在于推进学习成果的认定、累计与互换,进而为学习者在学习路径上提供更为灵活和便捷的选择。当前,我国学分银行建设和实施过程中,面临着社会的需求尚待提升、职业教育学分银行架构体系尚未健全、学分银行平台教育资源供应不足、学分认证存在挑战等困境。因此,要建好学分银行,应提升社会对学分银行的认可度,构建学分银行组织框架,加强教育资源的建设,建设统一的学分认证制度。

关键词：职业教育学分银行学习成果

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于高温超导的高精度电压互感器研究

引用

电测与仪表 2024年第4期61卷 48-55页

作者：刘浩刁赢龙何莹辉陈立学李小飞杨洪中国电力科学研究院有限公司武汉430074 华中科技大学电气与电子工程学院武汉430074

电压互感器的励磁误差由励磁电流在电压互感器绕组上的压降产生,是电压互感器误差的主要来源。双级励磁技术可以有效降低电压互感器的励磁电流,但绕组阻抗始终无法消除,励磁误差仍然存在。文中将77 K高温超导技术应用于电压互感器,绕组... 详细信息

电压互感器的励磁误差由励磁电流在电压互感器绕组上的压降产生,是电压互感器误差的主要来源。双级励磁技术可以有效降低电压互感器的励磁电流,但绕组阻抗始终无法消除,励磁误差仍然存在。文中将77 K高温超导技术应用于电压互感器,绕组和互感器铁心均工作在高温超导环境,达到超导态时绕组的阻抗为零,励磁电流经过绕组引起的压降也为零,可以从根本上消除励磁误差。分析了高温超导下的铜损和铁心磁性能,重点针对铁心的磁滞和涡流损耗进行了理论分析并提出抑制措施,设计了一台变比为1 kV/10 V的电压互感器的铁心和绕组结构,研制了高温超导电压互感器样机,设计了低温杜瓦容器及其外部冷屏设计,减小热量损失温度场,开展温度场仿真分析温度分布梯度。最后开展了误差校准,校准结果表明,该样机在20%~120%额定电压范围内,比值误差优于4×10-6,相位误差优于5μrad,比常温电压互感器的误差减小一个数量级。77 K高温超导电压互感器对于提升电压互感器的精度具有重要意义,同时也可为更高电压等级的超导互感器研制提供理论支撑。

关键词：电压互感器高温超导精密测量

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Rapid construction of phosphatase and tensin homolog-deleted on chromosome ten gene recombinant adenovirus using the AdEasy system

引用

Neural Regeneration Research 2010年第15期5卷 1166-1170页

作者： Yongqiong Wei lixue chen Zhaofang Zeng Chongbiao Shen Key Laboratory of Laboratory Medical Diagnostics Ministry of Education Chongqing Medical University Chongqing 400016 China Chongqing Key Laboratory of Neurology First Affiliated Hospital Chongqing Medical University Chongqing 400016 China

Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten （PTEN） gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely used, greatly simplifies preparation of recombinant adenovirus. Therefore, recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene （Ad-PTEN） was constructed using the AdEasy-1 system and was transfected into HEK293 cells for packaging and amplification. Infection efficiency and expression intensity were observed in primary cultured rat hippocampal neurons infected with Ad-PTEN in vitro. Results revealed a cytopathic effect in green fluorescent protein expression, which increased with prolonged time. After three cycles of amplification, the adenovirus titer was increased to an adequate titer for infecting hippocampal neurons. The entire process typically requires 4-5 weeks for completion. Results suggested that recombinant defective adenovirus vector carrying the PTEN gene was successfully and rapidly constructed using the AdEasy system.

关键词： phosphatase and tensin homolog-deleted on chromosome ten recombinant adenovirus AdEasy system vector construction nerve factors neural regeneration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Improvement of antibacterial, anti-inflammatory, and osteogenic properties of OGP loaded Co-MOF coating on titanium implants for advanced osseointegration

引用

Journal of Materials Science & Technology 2023年第15期146卷 131-144页

作者： Bailong Tao Weiwei Yi Xian Qin Junjie Wu Kai Li Ai Guo Jie Hao lixue chen Laboratory Research Center The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Rehabilitation Medicine The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Obstetrics and Gynecology Chongqing Health Center for Women and ChildrenChongqing 401147China Women and Children’s Hospital of Chongqing Medical University Chongqing 401147China Department of Orthopedics The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Orthopedics The Third Affiliated Hospital of Chongqing Medical UniversityChongqing 400016Chin

The bacterial infection,especially for methicillin-resistant Staphylococcus aureus(MRSA),and the associated severe inflammatory response could extremely limit the crosstalk of RAW264.7 cells and mesenchymal stem cells(MSCs)and lead to the undesirable osseointegration of peri–*** is highly demanded to modify the surface of titanium(Ti)implant to improve its anti-bacterial and anti-inflammatory properties and facilitate its disabled ***,in our study,a multifunctional coating of zeolitic imidazolate frameworks-67 encapsulated osteogenic growth peptide(OGP)(ZO)was fabricated on titanium dioxide nanotubes(TNT)substrates(TNT-ZO)via the electrophoresis deposition(EPD)*** TNT-ZO substrates exhibited excellent antibacterial activity indicated by the reactive oxygen species(ROS)generation,outer membrane(OM)and inner membrane(IM)permeabilization change,adenosine triphosphate(ATP)decrease,and intracellular compounds(DNA/RNA)***,the regulation effects of TNT-ZO coating modified titanium substrates on the RAW264.7-MSCs crosstalk could induce the anti-inflammatory and osteogenic microenvironment via multiple paracrine signaling of Runx2,BMP2,VEGF,and TGF-β*** promoted effects of coating structure were investigated in vivo,including antibacterial effect,osteogenic differentiation of mesenchymal stem cells,and anti-inflammation of RAW264.7 cells,as well as infected bone regeneration and repair in bone defect transplantation *** results demonstrated that MRSA was effectively eliminated by the hydrolysis of ZIF-67 nanoparticles on TNT-ZO ***,the excellent osseointegration of peri–implants was realized simultaneously by modulating the crosstalk of *** study could provide a novel approach to designing a multifunctional coating on the Ti implants for infected bone regeneration in orthopedic applications.

关键词： Titanium implants Osteogenic growth peptide Anti-inflammatory Antibacterial activity Osteoimmunomodulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Distribution of phosphorylated Elk-1 in rat brain after Y-maze active avoidance training in a temporal manner

引用

Neural Regeneration Research 2006年第3期1卷 193-196页

作者： Xuhong chen Siyun Shu Zhenjiang Liang Xinmin Bao lixue chen Yongming Wu Research Room of Neurobiology. Second Affiliated Hospital of Southern Medical University. Guangzhou 510282 Guangdong Province China Department of Otolaryngology Shenzhen Children＇s Hospital Shenzhen 518026 Guengdong Province China

BACKGROUND： Elk-1 mRNA distributes extensively in the neurons of mice, rat and human brains, and the Elk-1 expression may be correlated with the synaptic plasticity, learning and memory. OBJECTIVE： To observe the distribution of phosphorylated Elk-1 （pEIk-1） in whole brain of rats received Y-maze active avoidance training and the changes of pEIk-1 expression at different time points after training. DESIGN ： A randomized controlled study SETTING ： Research Room of Neurobiology, the Second Affiliated Hospital of Southern Medical University MATERIALS ： Fifty-five male clean-degree SD rats of 3-4 months old, weighing 200-250 g, were provided by the Experimental Animal Center of Southem Medical University. The rabbit anti-monoclonal pEIk-1 antibody was purchased from Cell Signal Transduction Company, and ABC kit from Vector Company. METHODS ： The experiments were carried out in the Research Room of Neurobiology, Second Affiliated Hospital of Southern Medical University from September 2004 to February 2005. ① Grouping： The rats were randomly divided into training group （n = 25）, sham-training group （n = 25） and normal control group （n = 5）, and the training and sham-training groups were observed at 0, 1, 3, 6 and 24 hours after training, which represented the five phases in the process of leaming and memory. ② Y-maze training： The rats were preconditioned in the electrical Y-maze apparatus, 20 minutes a day for 3 days continuously, and training began from the 4^th day. In the training group, the rats were trained with the combination of light and electddty. Each rat repeated for 60 times in each training, and the correct times were recorded, those correct for less than 25 times were taken as unqualified, and excluded from the training group, and supplemented by other rats in time. In the sham-training group, there was no fixed correlation between the application of light and electricity. The rats in the normal contrel group were given not any training. ③Detection of pEIk-

关键词： Distribution of phosphorylated Elk-1 in rat brain after Y-maze active avoidance training in a temporal manner

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Hybrid Optical-Electronic Implementation of Morphological Edge Detection

引用

Chinese Journal of Lasers 1994年第1期B3卷 83-90页

作者： YUAN Shifu ZHANG Xueru ZHAO Shijie LI Yan chen lixue(Department of Applied Physics,Harbin Institute of Technology,Harbin 150001,China) Harbin Inst of Technology Harbin China

ＨｙｂｒｉｄＯｐｔｉｃａｌ－ＥｌｅｃｔｒｏｎｉｃＩｍｐｌｅｍｅｎｔａｔｉｏｎｏｆＭｏｒｐｈｏｌｏｇｉｃａｌＥｄｇｅＤｅｔｅｃｔｉｏｎ￥ＹＵＡＮＳｈｉｆｕ；ＺＨＡＮＧＸｕｅｒｕ；ＺＨＡＯＳｈｉｊｉｅ；ＬＩＹａｎ；ＣＨＥ... 详细信息

ＨｙｂｒｉｄＯｐｔｉｃａｌ－ＥｌｅｃｔｒｏｎｉｃＩｍｐｌｅｍｅｎｔａｔｉｏｎｏｆＭｏｒｐｈｏｌｏｇｉｃａｌＥｄｇｅＤｅｔｅｃｔｉｏｎ￥ＹＵＡＮＳｈｉｆｕ；ＺＨＡＮＧＸｕｅｒｕ；ＺＨＡＯＳｈｉｊｉｅ；ＬＩＹａｎ；ＣＨＥＮＬｉｘｕｅ（Ｄｅｐａｒｔｍｅｎｔ...

关键词： edge detection morphological transformation optical information processing

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：