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郭志勤
《中国工程科学》 2000年 第2卷 第3期 页码 12-17
从我国养牛业的现状和存在的主要问题,指出养牛业需要大力发展,当前必须大量引种和繁殖种牛。 而胚胎移植是引种的一种最好手段,具有方法简便、成本低、缩短改良时间、减少疾病传播等优点。同时,进 一步分析了我国胚胎移植技术的研究概况,阐明了胚胎移植的主要技术关键及产业化的必要性和可能性。并根 据我国养牛业的现状,提出奶牛、肉牛业应用胚胎移植技术的措施与办法。
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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
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
Factors affecting early embryonic development in cattle: relevance for bovine cloning
Yanna DANG, Kun ZHANG
《农业科学与工程前沿(英文)》 2019年 第6卷 第1期 页码 33-41 doi: 10.15302/J-FASE-2018228
Female infertility represents a major challenge for improving the production efficiency in the dairy industry. Historically, fertility has declined whereas milk yield has increased tremendously due to intensive genetic selection. evidence reveals about 60% pregnancy loss takes place during the first month following fertilization. Meanwhile, early embryo development is significant for somatic cell nuclear transfer in cattle as a large proportion of cloned embryos fail to develop beyond peri-implantation stage. Oocyte quality is of utmost importance for the early embryo to develop to term for both fertilized and cloned embryos. Epigenetic reprogramming is a key process occurring after fertilization and critical roles of epigenetic modifiers during preimplantation development are now clear. Incomplete epigenetic reprogramming is believed to be a major limitation to cloning efficiency. Treatment of cloned embryos with epigenetic modifying drugs (e.g., Trichostatin A) could greatly improve cloning efficiency in both mice and cattle. Recently, the rapid progress in high-throughput sequencing technologies has enabled detailed deciphering of the molecular mechanisms underlying these events. The robust efficiency of genomic editing tools also presents an alternative approach to the functional annotation of genes critical to early development.
关键词: bovine cloning embryo development somatic cell nuclear transfer X-inactive specific transcript
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《医学前沿(英文)》 2017年 第11卷 第2期 页码 247-252 doi: 10.1007/s11684-017-0519-6
The activity of free radicals in follicular fluid was related to ovarian responsiveness, in vitro fertilization (IVF), and embryo transfer success rate. However, studies analyzing the relationship between the free radical scavenging capacity and embryo quality of infertile women with polycystic ovarian syndrome (PCOS) were lacking. The aim of this study was to evaluate the relationship between the free radical scavenging window of women with PCOS and their embryo quality. The free radical scavenging capacity of follicular fluid from women with PCOS was determined by a,a-diphenyl-b-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) assay, superoxide radical, and reactive oxygen species (ROS) assay. In the DPPH and ROS assays, the follicular fluid from grades I and II embryos was significantly higher than the follicular fluid from grades III and IV embryos. The lower control limit of DPPH radical scavenging capacity and upper control limit of ROS level were 13.2% and 109.0 cps, respectively. The calculated lower control limit and upper control limit were further confirmed in the follicular fluid of embryos of all grades. These cut-off values of free radical scavenging activity of follicular fluid could assist embryologists in choosing the development of embryos in PCOS patients undergoing IVF.
关键词: in vitro fertilization PCOS free radical embryo quality
Embryo-mediated genome editing for accelerated genetic improvement of livestock
Zachariah MCLEAN, Björn OBACK, Götz LAIBLE
《农业科学与工程前沿(英文)》 2020年 第7卷 第2期 页码 148-160 doi: 10.15302/J-FASE-2019305
Selecting beneficial DNA variants is the main goal of animal breeding. However, this process is inherently inefficient because each animal only carries a fraction of all desirable variants. Genome editing technology with its ability to directly introduce beneficial sequence variants offers new opportunities to modernize animal breeding by overcoming this biological limitation and accelerating genetic gains. To realize rapid genetic gain, precise edits need to be introduced into genomically-selected embryos, which minimizes the genetic lag. However, embryo-mediated precision editing by homology-directed repair (HDR) mechanisms is currently an inefficient process that often produces mosaic embryos and greatly limits the numbers of available edited embryos. This review provides a summary of genome editing in bovine embryos and proposes an embryo-mediated accelerated breeding scheme that overcomes the present efficiency limitations of HDR editing in bovine embryos. It integrates embryo-based genomic selection with precise multi-editing and uses embryonic cloning with elite edited blastomeres or embryonic pluripotent stem cells to resolve mosaicism, enable multiplex editing and multiply rare elite genotypes. Such a breeding strategy would enable a more targeted, accelerated approach for livestock improvement that allows stacking of beneficial variants, even including novel traits from outside the breeding population, in the most recent elite genetic background, essentially within a single generation.
关键词: animal breeding cattle cloning CRISPR/Cas9 cytoplasmic injection embryo genome editing germline chimaeras HDR livestock improvement TALENs
Reproductive toxicity study with a novel deoxyguanosine analogue (Metacavir) in pregnant SD rats
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《医学前沿(英文)》 2015年 第9卷 第1期 页码 82-89 doi: 10.1007/s11684-015-0376-0
Our preliminary studies demonstrated that Metacavir has potential to become a new anti-HBV agent. The main targets of the toxic effects of Metacavir, in rhesus monkeys, were gastrointestinal tracts, liver, blood, and kidneys, which were not related to mitochondrial effects. In this study, the maternal toxicity, embryo-fetal developmental toxicity and teratogenicity were studied in pregnant Sprague-Dawley rats after intragastric administration of Metacavir (200, 100, 50, 0 mg/kg body weight) during the first 6–15 days of pregnancy. Slower weight gain was observed in 5 out of 21 rats subjected to a 200 mg/kg dose, as well as 2 out of 20 subjected to a 100 mg/kg dose. Compared with the solvent control group, the calibration weight gain in the 200 mg/kg and 100 mg/kg dosage groups respectively, during first 6–20 pregnant days were significantly different (P<0.01, P<0.05). Significant dose related adverse effects to other reproductive parameters were not seen in F0 and F1, but the number of stillbirths in high dose group showed notably difference compared with the control group (P<0.05), while the litter incidence showed no difference. No Metacavir-associated pathological changes were observed. The present research indicated that at a dose of 200 mg/(kg·d) (i.e., 40 times the effective dose in rats), Metacavir shows some maternal toxicity to SD rats. The embryotoxicity in the 200 mg/kg group encompass decreased fetal body weight, and higher fetal mortality rates, compared with the control group. However, the litter incidence showed no statistical difference. All the treated rats displayed normal bone development, no teratogenicity and without adverse effects on fetal development, thus indicating that below a dose of 200 mg/(kg·d) there is no teratogenic side effects.
关键词: deoxyguanosine analogue Metacavir pregnancy maternal toxicity embryo toxicity teratogenicity
Augmentation of natural convective heat transfer by acoustic cavitation
Jun CAI, Xiulan HUAI, Shiqiang LIANG, Xunfeng LI,
《能源前沿(英文)》 2010年 第4卷 第3期 页码 313-318 doi: 10.1007/s11708-009-0064-3
关键词: heat transfer enhancement augmentation acoustic cavitation acoustic streaming convective heat transfer
Linlin LIANG, Bei XU, Guijin ZHU
《医学前沿(英文)》 2009年 第3卷 第2期 页码 220-226 doi: 10.1007/s11684-009-0037-2
关键词: gonadotropin-releasing hormone ovarian reserve embryo developmental ability ovarian surface epithelium
Effects of DNA damage on oocyte meiotic maturation and early embryonic development
Shen YIN,Junyu MA,Wei SHEN
《农业科学与工程前沿(英文)》 2014年 第1卷 第3期 页码 185-190 doi: 10.15302/J-FASE-2014035
Experimental study of heat transfer coefficient with rectangular baffle fin of solar air heater
Foued CHABANE,Nesrine HATRAF,Noureddine MOUMMI
《能源前沿(英文)》 2014年 第8卷 第2期 页码 160-172 doi: 10.1007/s11708-014-0321-y
关键词: Nusselt number flow rate heat transfer heat transfer coefficient thermal efficiency forced convection
Jizu LV, Minli BAI, Long ZHOU, Jian ZHOU,
《能源前沿(英文)》 2010年 第4卷 第3期 页码 392-401 doi: 10.1007/s11708-009-0066-1
关键词: heat transfer space non-uniformity soot emission in-cylinder diesel
Heat transfer coefficient of wheel rim of large capacity steam turbines
SHI Jinyuan, DENG Zhicheng, YANG Yu, JUN Ganwen
《能源前沿(英文)》 2008年 第2卷 第1期 页码 20-24 doi: 10.1007/s11708-008-0015-4
关键词: convection heat-transfer capacity heat-transfer coefficient bottom transmission
Review of the LNG intermediate fluid vaporizer and its heat transfer characteristics
《能源前沿(英文)》 2022年 第16卷 第3期 页码 429-444 doi: 10.1007/s11708-021-0747-y
关键词: intermediate fluid vaporizer design of structure and intermediate fluid condensation heat transfer
Improving hole transfer of boron nitride quantum dots modified PDI for efficient photodegradation
《化学科学与工程前沿(英文)》 2023年 第17卷 第11期 页码 1718-1727 doi: 10.1007/s11705-023-2319-7
关键词: PDI boron nitride quantum dots photocatalysis hole transfer
Cryopreservation of farm animal gametes and embryos: recent updates and progress
Zhengyuan HUANG, Lei GAO, Yunpeng HOU, Shien ZHU, Xiangwei FU
《农业科学与工程前沿(英文)》 2019年 第6卷 第1期 页码 42-53 doi: 10.15302/J-FASE-2018231
Cryopreservation has undergone tremendous advances and is widely used in animal production based on decades of study of cellular permeability, freezability and empirical generalization. Several improvement are particularly important: the cryopreservation protocol has been continuously refined over the years to achieve greater reproductive performance; cryoprotective agents are more effective and less toxic than previously; there has been significant innovation in advanced cryopreservation systems and carriers. Despite this, there are still problems that urgently require practical solutions, such as remedies for cryodamage and encouraging the use of frozen–thawed porcine sperm in pig production.
关键词: vitrification gametes embryo animal production cryoprotective agent freezability
标题 作者 时间 类型 操作
Propensity score-matched study and meta-analysis of cumulative outcomes of day 2/3 versus day 5/6 embryo
null
期刊论文
Factors affecting early embryonic development in cattle: relevance for bovine cloning
Yanna DANG, Kun ZHANG
期刊论文
Free radical scavenging window of infertile patients with polycystic ovary syndrome: correlation with embryo
null
期刊论文
Embryo-mediated genome editing for accelerated genetic improvement of livestock
Zachariah MCLEAN, Björn OBACK, Götz LAIBLE
期刊论文
Reproductive toxicity study with a novel deoxyguanosine analogue (Metacavir) in pregnant SD rats
null
期刊论文
Augmentation of natural convective heat transfer by acoustic cavitation
Jun CAI, Xiulan HUAI, Shiqiang LIANG, Xunfeng LI,
期刊论文
Effect of repeated gonadotropin stimulation on ovarian reserves and proliferation of ovarian surface epithelium in mice
Linlin LIANG, Bei XU, Guijin ZHU
期刊论文
Effects of DNA damage on oocyte meiotic maturation and early embryonic development
Shen YIN,Junyu MA,Wei SHEN
期刊论文
Experimental study of heat transfer coefficient with rectangular baffle fin of solar air heater
Foued CHABANE,Nesrine HATRAF,Noureddine MOUMMI
期刊论文
Effect of heat transfer space non-uniformity of combustion chamber components on in-cylinder heat transfer
Jizu LV, Minli BAI, Long ZHOU, Jian ZHOU,
期刊论文
Heat transfer coefficient of wheel rim of large capacity steam turbines
SHI Jinyuan, DENG Zhicheng, YANG Yu, JUN Ganwen
期刊论文
Improving hole transfer of boron nitride quantum dots modified PDI for efficient photodegradation
期刊论文