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71.
利用静电场提高IVF小鼠胚胎发育率的研究   总被引:3,自引:0,他引:3  
本研究首先用静电场处理小鼠2细胞期胚胎,通过观察其发育率筛选了最佳处理剂量(场强和时间),在此基础上探讨了不同细胞期的静电刺激对小鼠胚胎发育的影响。结果表明:用静电场处理小鼠2细胞期胚胎,能显著提高胚胎的发育能力,最佳处理剂量的囊胚率从42.4%提高到64.5%,囊胚孵化率从20.0%提高到44.8%,与对照组存在极显著差异(P<0.01)。不同细胞期胚胎对静电刺激的敏感性不同,其中1细胞(授精后6h)和2细胞期(授精后24h)胚胎对电场刺激较为敏感。  相似文献   
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Although the pig is considered an important model of human disease and an ideal animal for the preclinical testing of cell transplantation, the utility of this model has been hampered by a lack of genuine porcine embryonic stem cells. Here, we derived a porcine pluripotent stem cell (pPSC) line from day 5.5 blastocysts in a newly developed culture system based on MXV medium and a 5% oxygen atmosphere. The pPSCs had been passaged more than 75 times over two years, and the morphology of the colony was similar to that of human embryonic stem cells. Characterization and assessment showed that the pPSCs were alkaline phosphatase (AKP) positive, possessed normal karyotypes and expressed classic pluripotent markers, including OCT4, SOX2 and NANOG. In vitro differentiation through embryonic body formation and in vivo differentiation via teratoma formation in nude mice demonstrated that the pPSCs could differentiate into cells of the three germ layers. The pPSCs transfected with fuw-DsRed (pPSC-FDs) could be passaged with a stable expression of both DsRed and pluripotent markers. Notably, when pPSC-FDs were used as donor cells for somatic nuclear transfer, 11.52% of the reconstructed embryos developed into blastocysts, which was not significantly different from that of the reconstructed embryos derived from porcine embryonic fibroblasts. When pPSC-FDs were injected into day 4.5 blastocysts, they became involved in the in vitro embryonic development and contributed to the viscera of foetuses at day 50 of pregnancy as well as the developed placenta after the chimeric blastocysts were transferred into recipients. These findings indicated that the pPSCs were porcine pluripotent cells; that this would be a useful cell line for porcine genetic engineering and a valuable cell line for clarifying the molecular mechanism of pluripotency regulation in pigs.  相似文献   
74.
Summary Spanish families (n = 75) with at least one affected cystic fibrosis (CF) child were typed for restriction fragment length polymorphisms (RFLPs) by the probes XV2c, KM19, and pMP6d-9. These families were also studied at the 508 mutation site by the polymerase chain reaction method. We have studied the linkage disequilibrium between these markers and the CF mutations, the probable number of independent secondary CFX (non-ΔF508) mutations, and the genetic differences between Spain and Western Europe.  相似文献   
75.
A Boué  J Boué  S Cure  C Deluchat  N Perraudin 《In vitro》1975,11(6):409-413
During a cytogenetic study of human spontaneous abortions, attempts were made to initiate cell lines from tissues of embryos with chromosomal anomalies. The rate of success of these attempts and the life-span of the cell cultures is correlated with the development attained by these aneusomic embryos.  相似文献   
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Chromosomal analysis of two consecutive abortuses in each of 43 women   总被引:2,自引:0,他引:2  
J Boué  A Boué 《Humangenetik》1973,19(3):275-280
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79.
The request for prenatal diagnosis of cystic fibrosis has been evaluated by an interview during a visit at a cystic fibrosis clinic among 32 couples whose one or several children are affected. Six couples resorted to the procedure between June 1984 and October 1985. In all the cases, in these families the only child (or children) alive was affected. The diagnosis of the disease in the first affected child reduces the number of children planned by the family. The significant use of the test, since its availability points to the existence of a real demand from the parents.  相似文献   
80.
The preparation fo five monoclonal antibodies specific of important human renal histologic structures both functionally and organogenetically has permitted to identify the repartition of the corresponding antigens in the vertebrate phylum. For three of them, appeared a clear cut histologic identity in intensity and localization between the mammals studied and man. For the two others a phylogenic and histologic dispersion was observed. It may be supposed, in the latter case, that the evolution and the biotope have acted in different manners on renal function and organogenesis according to the vertebrate classes or species investigated.  相似文献   
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