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Effect of leptin on oocyte maturation and subsequent pregnancy rate of cloned embryos reconstructed by somatic cell nuclear transfer in pigs 总被引:1,自引:0,他引:1
Hengxi Wei Qiuyan Li Jun Li Yan Li Yunping Dai Yufang Ma Kai Xue Ning Li 《自然科学进展(英文版)》2008,18(12):1583-1588
Cloning pigs by somatic cell nuclear transfer (SCNT) has wide applications in basic research, human medicine and agricultural production. To improve cloning efficiency, the effect of two basic maturation media, NCSU-23 and TCM199, was compared, and TCM199 was selected for the following experiments with leptin. We systematically studied the effects of leptin supplementation on oocytes in vitro maturation (IVM), in vitro development of parthenogenetically activated (PA) and SCNT embryos and in vivo development of SCNT embryos after embryo transfer (ET). The results showed that supplementation of 100 or 200 ng/ml leptin into the maturation medium did not greatly affect nuclear maturation of oocytes, or cleavage rates of PA and SCNT (P 〉 0.05). Blastocyst rates of PA and SCNT embryos were significantly improved when 100 or 200 ng/ml leptin was added to maturation medium, and the number of cells in PA blastocysts was also improved (P 〈 0.05). The number of cells in blastocyst of SCNT was improved, when 100 ng/ml leptin was added (P 〈 0.05). Furthermore, supplementation of 100 or 200 ng/ml leptin to the IVM medium may improve pregnancy rate and the delivery rate inpig cloning. 相似文献
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如果你还没有怀孕,不要那么快地下结论认为自己不育。下面这10个习惯,可能会使你面临不能怀孕的困扰。1、没有足够的性生活这是一个很简单的道理,发生性关系的次数越多,怀孕的机会便会越多。很多夫妇想要宝宝时,两周有1~2次性生活,甚至每周一次,但即使这样可能仍然是不够的。 相似文献
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平素电视、报刊、杂志处处可见“意外怀孕”怎么办?
当今社会,医学伴随着科技不断进步,不断完善,但却永无止境,比如:早期妊娠的终止由刮宫术改进为吸宫术,药物流产进而发展为目前最受患者青睐的“无痛人流”,“无痛人流”确实是无痛,但人们有没有思考过:“无痛人流”是怎样的手术?它与一般人工流产有何不同?对身体有没有伤害? 相似文献
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将采自屠宰母牛卵巢的未成熟卵子在含有促进性腺激素和胎牛血清的TCM199培养基内培养成熟后,使用以钙离子载体Ionophore A23187诱导获能的牛精子进行授精处理.在受精卵发育用培养基中添加了谷氨酰胺,并以此与无添对照进行了对比,探索了培养基内谷氨酰胺的存在与否对胚胎发育的影响.另外,在发育用培养基内还分别添加了胎牛血清(FCS),阉牛血清(NSS)以及发情母牛血清(OCS)以观察其培养效果,结果表明,谷氨酰胺对胚胎的发育有极大的促进作用,添加谷氨酰胺的处理组与对照组中发育为桑椹胚、囊胚的胚胎比例分别为23.4%和6.6%,具有极显著的整异.而在含有FCS、NSS和OCS的TCM199培养基内培养的卵子中分别有81.4%,70.7%和82.9%发育为二细胞期胚胎,将胚胎继续培养至授精后第8天时,三个处理组中发育为桑椹胚、囊胚的胚胎比例分别为30.0%,40.2%和47.1%,以OCS的培养效果为最佳.本研究的结果证明,谷氨酰胺和发情母牛血清对牛体外受精卵的体外发育具有良好的促进作用. 相似文献
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采用CDJ—8711型兽医用超声多普勒检测仪对3917头黄牛进行了早期怀孕诊断,并与直肠检查法相比较,其符合率高,最早测出宫血音、胎心音、胎血音的时间分别为20天、54天、58天。宫血音诊断与直肠检查法诊断其符合率在配种后20~30天、31~60天分别为97.91%(2624/2680)、100%(1001/1001),在配种后未怀孕的母牛为100%(236/236)。试验结果证明:检测到宫血音的时间比胎心音、胎血音早34~38天,与直肠检查法相比较,其符合率高;与血浆孕酮含量水平相比较,其符合率是一致的。因此,检测宫血音可作为黄牛的早期怀孕诊断的主要依据。 相似文献