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91.
92.
The influence of oocyte maturity and embryo quality on pregnancy rate in a program for in vitro fertilization-embryo transfer 总被引:6,自引:0,他引:6
G A Hill M Freeman M C Bastias B J Rogers C M Herbert K G Osteen A C Wentz 《Fertility and sterility》1989,52(5):801-806
An important factor influencing the pregnancy rate after in vitro fertilization-embryo transfer (IVF-ET) appears to be the number of embryos transferred to the uterus. In this study, the influence of oocyte maturity and embryo quality on pregnancy rate was assessed in patients undergoing IVF-ET. Ovarian hyperstimulation was performed by human menopausal gonadotropin (hMG [n = 29]), clomiphene citrate (CC)/hMG (n = 81), and hMG/follicle-stimulating hormone (FSH [n = 13]) protocols. Oocyte maturity was graded on a scale from 1 to 5 based on the morphology of the ooplasm, cumulus mass, corona radiata, and membrana granulosa cells. Embryos were graded according to the symmetry of the blastomeres and the presence or absence of fragmentation. Mature preovulatory oocytes yielded the highest fertilization rates. No differences were found among the protocols in terms of fertilization rate, embryo quality, or pregnancy rate. When all protocols were combined, patients who conceived had a significantly higher number of embryos transferred than those who did not conceive (3.6 +/- 0.1 [mean = SEM] versus 2.7 +/- 0.1). When embryo quality was compared, there was no difference in the number of "B" embryos transferred between patients who conceived and those who did not (1.2 +/- 0.2 versus 1.2 +/- 0.1), but the patients who conceived had significantly more "A" embryos transferred (1.6 +/- 0.3 versus 0.8 +/- 0.1). These data suggest that the treatment protocol did not determine embryo quality. Furthermore, the increase in pregnancy rates seen with an increase in embryos transferred is the result of the transfer of more "A" embryos. 相似文献
93.
94.
Ehab Samuel Ahmed M. Nabawy Agnes M. Samuel Herbert W. Doty Victor Songmene Fawzy H. Samuel 《Materials》2022,15(13)
The present work investigated the effect of aging treatment on the microstructure and tensile properties of an Al-2%Cu base alloy containing various additions of Zr and other alloying elements. Aging was carried out at temperatures of 180–300 °C for different aging times at each temperature. The tensile properties indicated that Zr additions improved the strength of the base alloy, especially at high Zr levels at 180 °C. At the 220 °C aging temperature, however, while Zr addition did not have a beneficial effect on the alloy strength, the ductility was found to improve. Zr-Ti combined additions had a significant effect on the microstructure of the base alloy, as the morphology of the α-Al grains transformed into a non-dendritic morphology, and the grain size decreased sharply. These effects were at their maximum at 180 °C and 0.5 wt% Zr addition. Moreover, the Zr-containing alloys aged at higher temperatures, such as 220 °C and 240 °C, maintained a noticeably higher level of strength over the base alloy aged at the same temperatures. Quality index charts based on the tensile test data also reflected an improvement in alloy quality and strength with Zr-Ti combined additions. 相似文献
95.
96.
Herbert Schwiegk 《Journal of molecular medicine (Berlin, Germany)》1951,29(41-42):710-710
97.
Journal of Molecular Medicine - Es wird über einen 59jährigen Landwirt berichtet, der seit 4 Jahren wegen einer isolierten aplastischen Anämie in Behandlung ist. Während dieser... 相似文献
98.
Ohne Zusammenfassung 相似文献
99.
Herbert M. Evans Miriam E. Simpson Paul R. Austin 《The Journal of experimental medicine》1933,57(6):897-906
The increased gonadotropic effect obtained by combining prolan with hypophyseal extracts can be secured equally well by the use of preparations which contain high amounts of the growth or of the gonad-stimulating hormone. In hypophyseal extracts containing the growth hormone, the synergistic effects do not parallel the content of growth-promoting substance. Similarly, in hypophyseal extracts containing the gonad-stimulating hormone, the synergistic effects do not parallel the content in the gonadotropic factor. The hypophyseal substance involved has been prepared sufficiently free of the growth and gonad-stimulating hormones to make it inadmissible to consider either of these substances as responsible for the reaction. 相似文献
100.