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Propensity score-matched study and meta-analysis of cumulative outcomes of day 2/3 versus day 5/6 embryo

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《医学前沿（英文）》 2017年第11卷第4期页码 563-569 doi: 10.1007/s11684-017-0535-6

摘要：

The superiority of the cumulative outcomes of day 5/6 embryo transfer to those of day 2/3 embryo transfer in infertile couples has been debated. This retrospective study included data collected from 1051 patients from July 2011 to June 2014. Multiple maternal baseline covariates were subjected to propensity score matching analysis, and each day 5/6 group woman was matched to one day 2/3 group woman. A systematic meta-analysis was conducted to validate the results. After matching was completed, 217 patients on the day 2/3 group were matched with those on the day 5/6 group, and no significant differences in the baseline characteristics were observed between the two groups. The cumulative pregnancy rate (57.14% vs. 53.46%, OR 1.16, 95% CI 0.79–1.70) and cumulative live birth rate (53.00% vs. 49.77%, OR 1.14, 95% CI 0.78–1.66) of day 5/6 embryo transfers were higher than those of day 2/3 embryo transfers, but this difference was not significant. The mean cycles per live birth and mean days per live birth in the day 5/6 group were significantly lower than those in the day 2/3 group. This study demonstrated that day 5/6 embryo transfer is a more cost-effective and time-efficient policy than day 2/3 embryo transfer to produce a live baby.

关键词： blastocyst embryo transfer cumulative pregnancy rate cumulative live birth rate IVF

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Advancing pediatric care before birth

《医学前沿（英文）》 2023年第17卷第2期页码 352-354 doi: 10.1007/s11684-022-0974-6

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广州市2 046例孕前育龄妇女TORCH检查状况分析

余志衡

《中国工程科学》 2014年第16卷第5期页码 63-66

摘要：

采用酶联免疫吸附试验(ELISA) 对2013 年1 月—2013 年12 月进行孕前筛查和孕早期普查的2 046 例妇女进行TORCH 特异性IgM 和IgG 抗体检测，主要检测RV-IgG、TOXO-IgG、TOXO-IgM、CMVIgG、CMV-IgM 五项。在调查的2 046 例妇女中，TORCH-IgM 总阳性率为0. 88 %，其中以巨细胞病毒(CMV)感染率居高，为0.68%，弓形虫（TOXO）为0. 20%。TORCH－IgG 阳性率以CMV最高，达97.65 %，其次为RV-IgG、TOXO-IgG，分别为85.58 %和4.89 %。广州市孕前和孕早期妇女TORCH感染率较高，应该积极进行监测和宣传，早发现，早干预，提高出生人口素质，减少出生缺陷与残疾发生。

关键词： TORCH 感染率酶联免疫吸附试验出生缺陷孕前检查

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青藏高原多年冻土地带爆破研究

何广沂

《中国工程科学》 2001年第3卷第6期页码 57-64

摘要：

介绍了青藏高原多年冻土地带铁路试验工程中有关爆破方面的研究成果，针对多年冻土的特征，重点论述了爆破方法与工艺及先进实用的聚能爆破技术。

关键词：多年冻土路堑基坑钻孔聚能弹聚能爆破

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Nonlinear cumulative damage model for multiaxial fatigue

SHANG De-guang, SUN Guo-qin, DENG Jing, YAN Chu-liang

《机械工程前沿（英文）》 2006年第1卷第3期页码 265-269 doi: 10.1007/s11465-006-0035-x

摘要： On the basis of the continuum fatigue damage theory, a nonlinear uniaxial fatigue cumulative damage model is first proposed. In order to describe multiaxial fatigue damage characteristics, a nonlinear multiaxial fatigue cumulative damage model is developed based on the critical plane approach. The proposed model can consider the multiaxial fatigue limit, mean hydrostatic pressure and the unseparated characteristic for the damage variables and loading parameters. The recurrence formula of fatigue damage model was derived under multilevel loading, which is used to predict multiaxial fatigue life. The results showed that the proposed nonlinear multiaxial fatigue cumulative damage model is better than Miner s rule.

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displacement caused by seismic liquefaction and performing parametric sensitivity analysis: Considering cumulative

Nima PIRHADI, Xiaowei TANG, Qing YANG, Afshin ASADI, Hazem Samih MOHAMED

《结构与土木工程前沿（英文）》 2021年第15卷第2期页码 506-519 doi: 10.1007/s11709-021-0677-0

摘要： Lateral displacement due to liquefaction ( ) is the most destructive effect of earthquakes in saturated loose or semi-loose sandy soil. Among all earthquake parameters, the standardized cumulative absolute velocity ( ) exhibits the largest correlation with increasing pore water pressure and liquefaction. Furthermore, the complex effect o fine content( ) at different values has been studied and demonstrated. Nevertheless, these two contexts have not been entered into empirical and semi-empirical models to predict This study bridges this gap by adding to the data set and developing two artificial neural network (ANN) models. The first model is based on the entire range of the parameters, whereas the second model is based on the samples with values that are less than the 28% critical value. The results demonstrate the higher accuracy of the second model that is developed even with less data. Additionally, according to the uncertainties in the geotechnical and earthquake parameters, sensitivity analysis was performed via Monte Carlo simulation (MCS) using the second developed ANN model that exhibited higher accuracy. The results demonstrated the significant influence of the uncertainties of earthquake parameters on predicting

关键词： lateral spreading displacement cumulative absolute velocity fine content artificial neural network sensitivity analysis Monte Carlo simulation

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免费孕前优生健康检查对象潜在危险因素接触和妊娠结局分析

车焱,周公望,王彩琴,张焕玲,张建娥,闫立新,陆珍,陆梅,沈洁,朱昊平

《中国工程科学》 2014年第16卷第5期页码 56-59

摘要：

分析并报告上海市静安区免费孕前优生健康检查后待孕夫妇不良妊娠结局潜在影响因素接触情况以及妊娠率和妊娠结局，为免费孕前健康检查政府实施项目效果的评估提供基础数据。对2011 年8 月—2012 年11 月在静安区参加免费孕前优生健康检查的所有对象在其检查结束后的3 个月、6 个月、12 个月进行随访，重点关注不良妊娠结局潜在危险因素接触情况以及妊娠时间和妊娠结局。统计方法为χ2检验、寿命表、Logistic 回归分析。在目标时段内共有1 480 对夫妇参加了免费孕前优生健康检查，其中1 249 对服务对象接受了随访，随访率为84.4 %。截至2013 年4 月，48.7 %的随访对象已经受孕，孕前检查后3 个月调查累积妊娠率为23.9 %，6 个月调查累积妊娠率为45.0 %。365 人完成妊娠结局的随访，结果显示，早产率为3.0 %，低出生体重率为4.3 %，巨大儿发生率为3.3 %。自然流产率为6.3 %。另外，发现出生缺陷1 人，占妊娠妇女数的0.16 %，占有妊娠结局妇女数的0.27 %。烟酒等不良生活习惯丈夫的比例（18 %～20 %）高于妻子（1 %～3 %），77 %的丈夫和妻子接受潜在电磁辐射的时间超过8 h。9 %的夫妇自述生活和工作中接触重金属以及农药、化肥等潜在致畸物。超过10 %的妻子在怀孕以后接触了潜在致畸物。初步分析未发现上述因素与不良妊娠结局的关系。静安区孕前健康检查后半年内妇女妊娠率不到50 %，有必要在上海乃至全国开展免费孕前健康检查的成本效益评估。

关键词：孕前优生健康检查妊娠率累积妊娠率不良妊娠结局危险因素

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确定性疲劳累积损伤理论进展

杨晓华,姚卫星,段成美

《中国工程科学》 2003年第5卷第4期页码 81-87

摘要：

著名的Miner-Palmgren线性累积损伤理论的提出已有70余年，但由于疲劳问题的复杂性，迄今为止还没有一个模型的工程应用价值能与该理论媲美。疲劳累积损伤理论仍在发展与完善中。文章根据疲劳损伤与疲劳累积损伤理论的特点，将确定性疲劳累积损伤理论分成两大类，即线性累积损伤理论和非线性累积损伤理论，并将主要的非线性累积损伤理论分成五类：a. 基于损伤曲线法的非线性累积损伤理论；b. 基于材料物理性能退化概念的非线性累积损伤理论；c. 基于连续损伤力学概念的非线性累积损伤理论；d. 考虑载荷间相互作用效应的非线性累积损伤理论；e. 基于能量法的非线性累积损伤理论。文章分析了每一类模型中有代表性模型的物理背景，回答了模型在疲劳累积损伤理论中存在的主要问题，简要评述了模型的优缺点，讨论了确定性疲劳累积损伤理论的几个关键问题。

关键词：疲劳线性与非线性累积损伤损伤力学能量

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advances in small molecule fluorescent probes for simultaneous imaging of two bioactive molecules in live

Yongqing Zhou, Xin Wang, Wei Zhang, Bo Tang, Ping Li

《化学科学与工程前沿（英文）》 2022年第16卷第1期页码 4-33 doi: 10.1007/s11705-021-2041-2

摘要： The interrelationships and synergistic regulations of bioactive molecules play pivotal roles in physiological and pathological processes involved in the initiation and development of some diseases, such as cancer and neurodegenerative and cardiovascular diseases. Therefore, the simultaneous, accurate and timely detection of two bioactive molecules is crucial to explore their roles and pathological mechanisms in related diseases. Fluorescence imaging associated with small molecular probes has been widely used in the imaging of bioactive molecules in living cells and due to its excellent performances, including high sensitivity and selectivity, noninvasive properties, real-time and high spatial temporal resolution. Single organic molecule fluorescent probes have been successively developed to simultaneously monitor two biomolecules to uncover their synergistic relationships in living systems. Hence, in this review, we focus on summarizing the design strategies, classifications, and bioimaging applications of dual-response fluorescent probes over the past decade. Furthermore, future research directions in this field are proposed.

关键词： bioactive molecules fluorescent probes in living cells and in vivo review

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全球首例猪心脏移植人体手术

Sarah C. P. Williams

《工程（英文）》 2022年第16卷第9期页码 6-8 doi: 10.1016/j.eng.2022.07.006

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An update and cumulative meta-analysis

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《医学前沿（英文）》 2014年第8卷第2期页码 241-249 doi: 10.1007/s11684-014-0328-0

摘要：

Approximately 70% of newly diagnosed bladder tumors are non-muscle invasive bladder cancer (NMIBC). NMIBC accounts for approximately 80% of total bladder cancer cases. Bacillus Calmette-Guérin (BCG) instillation and maintenance is considered as the standard adjuvant treatment for superficial bladder cancer. A number of randomized studies have focused on the benefit of maintenance therapy following initial BCG induction. To provide further insights into the effect of intravesical instillation on recurrence in patients with NMIBC, we analyzed this relationship by conducting an updated detailed meta-analysis. Evidence suggested that adjuvant intravesical BCG with maintenance treatment is significantly effective for the prophylaxis of tumor recurrence in patients with NMIBC.

关键词： non-muscle invasive bladder cancer bacillus Calmette-Guérin (BCG) meta-analysis

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Comparison of birth weight and umbilical and placental characteristics of cloned and artificial insemination-derived

Zheng AO, Chengfa ZHAO, Yanmin GAN, Xiao WU, Junsong SHI, Enqin ZHENG, Dewu LIU, Gengyuan CAI, Zhenfang WU, Zicong LI

《农业科学与工程前沿（英文）》 2019年第6卷第1期页码 54-60 doi: 10.15302/J-FASE-2018249

摘要：

Somatic cell nuclear transfer (SCNT)-derived piglets have significantly higher stillbirth rate and postnatal mortality rate than artificial insemination (AI)-generated piglets. The question whether the low survival rate of SCNT piglets was related to birth weight, umbilical cord or placenta development was investigated. In this study, stillbirth rate, neonatal death rate, birth weight, umbilical cord status, placental parameters and placental gene expression patterns were compared between SCNT and AI piglets. Results showed that mortality rates at birth and during the neonatal stage of SCNT piglets were significantly higher than those of AI piglets. The incidence of abnormal umbilical cord in SCNT and SCNT-liveborn (SCNT-LB) piglets was significantly higher than in AI and AI-liveborn (AI-LB) piglets. Birth weight, placental weight, placental surface area and placental efficiency in SCNT and SCNT-LB piglets were significantly lower than those of AI and AI-LB piglets. Placental expression profiles of imprinting, angiopoiesis and nutrient transport-related genes were defective in SCNT-LB piglets compared with those in AI-LB piglets. Thus, the low survival rate of SCNT piglets may be associated with abnormal umbilical cord and placenta development. These characteristics may have resulted from aberrant expression of angiogenesis, nutrient transport, and imprinting-related genes in the placentas.

关键词： cloned pig death placenta SCNT umbilical cord

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The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

《环境科学与工程前沿（英文）》 2021年第15卷第6期 doi: 10.1007/s11783-021-1411-9

摘要：

• Actual SAORs was determined using MLVSS and temperature.

关键词： Specific ammonia oxidation rate Sequencing batch reactor Biomass Temperature coefficient Model simulation

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Use of float consumption rate in resource leveling of construction projects

Atilla DAMCI, Gul POLAT, Firat Dogu AKIN, Harun TURKOGLU

《工程管理前沿（英文）》 2022年第9卷第1期页码 135-147 doi: 10.1007/s42524-020-0118-0

摘要： The management of resources has been claimed to be as important as scheduling methods. Inefficiency in managing resources may bring about severe delays and cost overruns caused by resource shortages in some cases and/or idle resources in others. Therefore, resources should be utilized efficiently to prevent project failures. Resource leveling is one of the approaches that are used for the management of resources. It aims to minimize fluctuations, peaks, and valleys in resource utilization without changing the completion time of a project and the number of resources required. Although the main principle behind traditional resource leveling is achieving an even flow of resources while the original project duration remains unchanged, the literature supports the need to develop an efficient model that discriminates among the activities that are selected for participation in resource leveling. For this purpose, this study has developed a model that considers the float consumption rates of activities in resource leveling. The float consumption rate is the percentage that is set to determine the maximum amount of float which will be consumed to shift the start time of the activity. The proposed model allows a scheduler to assign float consumption rates to each activity that can be used during the resource leveling procedure. When the required information is inputted, the proposed model automatically changes the required daily resources as it shifts the noncritical activities along their available total float times. The proposed model is expected to minimize the likelihood of severe delays and cost overruns. The model is demonstrated by constructing a network and its resource utilization histograms.

关键词： resource management resource leveling float consumption rate scheduling

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RR1 and RR2 gene deletion affects the immunogenicity of a live attenuated pseudorabies

Shijun YAN,He YAN,Chaolin ZHANG,Tongyan WANG,Qingyuan YANG,Zhe SUN,Yan XIAO,Feifei TAN,Xiangdong LI,Kegong TIAN

《农业科学与工程前沿（英文）》 2016年第3卷第1期页码 81-86 doi: 10.15302/J-FASE-2016088

摘要： As virulence-determining genes, and encode the small subunit and large subunit of viral ribonucleotide reductase (RR) in pseudorabies virus which have been extensively studied in mice. However, their role in pigs has not been adequately investigated. In this study, we deleted and genes based on a / / triple gene-deleted pseudorabies virus and tested its efficacy in pigs as a vaccine candidate. The rescued virus showed similar growth properties and plaque size as its parent strain. In an animal study, the virus could elicit humoral immune responses shown by generation of gB-specific antibodies and virus neutralizing antibodies. However, vaccination could not provide protection against virulent pseudorabies virus challenge since vaccinated pigs showed clinical pseudorabies-specific syndromes. The deficiency in protection may due to the generation of late and low levels of gB antibodies and virus neutralizing antibodies.

关键词： pseudorabies virus RR1 and RR2 ribonucleotide reductase vaccine candidate