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排序方式: 共有330条查询结果,搜索用时 46 毫秒
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72.
Jianjun Hu Carl Lessard Charles Longstaff Marilyn O'Brien Kristina Palmer Laura Reinholdt John Eppig John Schimenti Mary Ann Handel 《Molecular reproduction and development》2019,86(4):416-425
Given attention to both contraception and treatment of infertility, there is a need to identify genes and sequence variants required for mammalian fertility. Recent unbiased mutagenesis strategies have expanded horizons of genetic control of reproduction. Here we show that male mice homozygous for the ethyl‐nitroso‐urea‐induced ferf1 (fertilization failure 1) mutation are infertile, producing apparently normal sperm that does not fertilize oocytes in standard fertilization in vitro fertilization assays. The ferf1 mutation is a single‐base change in the Dnah1 gene, encoding an axoneme‐associated dynein heavy chain, and previously associated with male infertility in both mice and humans. This missense mutation causes a single‐amino‐acid change in the DNAH1 protein in ferf1 mutant mice that leads to abnormal sperm clumping, aberrant sperm motility, and the inability of sperm to penetrate the oocyte's zona pellucida; however, the ferf1 mutant sperm is competent to fertilize zona‐free oocytes. Taken together, the various mutations affecting the DNAH1 protein in both mouse and human produce a diversity of phenotypes with both subtle and considerable differences. Thus, future identification of the interacting partners of DNAH1 might lead to understanding its unique function among the sperm dyneins. 相似文献
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74.
Thomas Jensen Sarah E. Jamieson Isabel Castro Brett Gartrell John F. Cockrem Barbara Durrant 《Zoo biology》2019,38(3):316-320
In brown kiwi (Apteryx mantelli), the male is the primary incubator, a trait that is relatively rare among birds. The maintenance of avian incubation behavior is controlled by the protein hormone prolactin (PRL). Although steroid hormone concentrations in both wild and captive kiwi have previously been reported, this study is the first to report levels of PRL in captive and wild male and female kiwi through the prebreeding and breeding seasons, and to directly compare testosterone (T) concentrations between captive and wild males during the breeding and incubation periods. Female PRL concentrations increased at the time of oviposition, whereas male PRL concentrations rose gradually between the prebreeding and incubation periods. Although males are considered the main incubator, an increase in PRL levels could help females maintain behaviors such as nest guarding, or to take over incubation the event of mate loss. A gradual increase in PRL allows the male to be ready for incubation during the long breeding season. Interestingly, T concentrations in captive males did not decrease during incubation and was significantly higher than in wild males. Continual elevated T could have an impact on sperm production through negative feedback, thereby contributing to the low egg fertility seen in captive kiwi. Therefore, determining the underlying reason for the differences in hormone levels could be significant, if not vital, for improving the success of captive kiwi breeding programs. 相似文献
75.
Ana Kolarevic Aleksandra Pavlovic Aleksandra Djordjevic Jelena Lazarevic Sasa Savic Gordana Kocic Marko Anderluh Andrija Smelcerovic 《化学与生物多样性》2019,16(5)
DNase I inhibitory potential of water extract of nine Hypericum species (H. umbellatum, H. barbatum, H. rumeliacum, H. rochelii, H. perforatum, H. tetrapterum, H. olympicum, H. hirsutum, H. linarioides) and the most important Hypericum secondary metabolites (hypericin, hyperforin, quercetin, and rutin) was investigated. All examined Hypericum extracts inhibited DNase I with IC50 below 800 μg/ml, whereby H. perforatum was the most potent (IC50=391.26±68.40 μg/ml). Among the investigated Hypericum secondary metabolites, rutin inhibited bovine pancreatic DNase I in a non‐competitive manner with IC50 value of 108.90±9.73 μm . DNase I inhibitory ability of rutin was further confirmed on DNase I in rat liver homogenate (IC50=137.17±16.65 μm ). Due to the involvement of DNase I in apoptotic processes the results of this study indicate the importance of frequent rutin and H. perforatum consumption in daily human nutrition. Rutin is a dietary component that can contribute to male infertility prevention by showing dual mechanism of sperm DNA protection, DNase I inhibition and antioxidant activity. 相似文献
76.
《Reproductive biology》2019,19(3):299-302
We conducted a single-center cross-sectional study to determine whether scrotal-testicular tissue oxygen saturation (S-T StO2) measured by finger-mounted near-infrared spectroscopy is useful for the evaluation of testicular function. S-T StO2 was significantly higher in patients with nonobstructive azoospermia (NOA, p< 0.05), and showed a positive correlation with luteinizing hormone levels (LH) even in participants without NOA (r = 0.34, p< 0.05), suggesting that elevated S-T StO2 is associated with a reduction in testicular function. 相似文献
77.
摘要 目的:探讨与评价全氟显子宫输卵管四维超声造影(4D-HyCoSy)与经阴道三维超声输卵管造影(3D-HyCoSy)对输卵管性不孕症患者的诊断效果。方法:选择2018年8月到2021年11月选择在本院诊治的女性不孕症患者84例作为研究对象,都给予全氟显4D-HyCoSy与3D-HyCoSy诊断,记录图像质量与不良反应发生情况。金标准为腹腔镜检查,判断诊断效果。结果:在84例患者中,全氟显4D-HyCoSy的图像质量优良率为100.0 %,高于3D-HyCoSy的92.9 %(P<0.05)。全氟显4D-HyCoSy诊断为输卵管通畅14例,输卵管通而不畅23例,输卵管阻塞47例。3D-HyCoSy诊断:22例输卵管通畅,21例输卵管通而不畅,41例输卵管阻塞。腹腔镜诊断:15例输卵管通畅,21例输卵管通而不畅,48例输卵管阻塞。全氟显4D-HyCoSy、3D-HyCoSy对输卵管性不孕症患者的诊断敏感性为100.0 %(36/36)、97.2 %(35/36),特异性为97.9 %(47/48)、83.3 %(40/48)。84例患者在全氟显4D-HyCoSy、3D-HyCoSy检查期间发生的不良反应主要为阴道出血、恶心呕吐、腹部疼痛等,不良反应发生率对比无差异(P>0.05)。全氟显4D-HyCoSy对输卵管性不孕症患者的诊断敏感性与3D-HyCoSy对比无差异(P>0.05),诊断特异性高于3D-HyCoSy(P<0.05)。结论:相对于3D-HyCoSy,全氟显4D-HyCoSy在输卵管性不孕症患者的应用能提高图像质量优良率,具有很好的安全性,还具有更好的诊断特异性。 相似文献
78.
Sperm are particularly prone to oxidative damage because they generate reactive oxygen species (ROS), have a high polyunsaturated fat content and a reduced capacity to repair DNA damage. The dietary compounds vitamin E and beta-carotene are argued to have antioxidant properties that help to counter the damaging effects of excess ROS. Here in, we tested the post-copulatory consequences for male crickets (Teleogryllus oceanicus) of dietary intake of these two candidate antioxidants. During competitive fertilisation trials, vitamin E, but not beta-carotene, singularly enhanced sperm competitiveness. However, the diet combining a high vitamin E dose and beta-carotene produced males with the most competitive ejaculates, possibly due to the known ability of beta-carotene to recycle vitamin E. Our results provide support for the idea that these two common dietary compounds have interactive antioxidant properties in vivo, by affecting the outcomes of male reproductive success under competitive conditions. 相似文献
79.
80.
Inhorn MC 《Medical anthropology quarterly》2006,20(1):94-120
In the Sunni Muslim world, religious mandates prohibit both adoption and gamete donation as solutions to infertility, including in the aftermath of in vitro fertilization (IVF) failures. However, both of these options are now available in two Middle Eastern countries with significant Shi'ite Muslim populations (Iran and Lebanon). On the basis of fieldwork in multisectarian Lebanon, I examine in this article attitudes toward both adoption and gamete donation among childless Muslim men who are undertaking IVF with their wives. No matter the religious sect, most Muslim men in Lebanon continue to resist both adoption and gamete donation, arguing that such a child "won't be my son". However, against all odds, some Muslim men are considering and undertaking these alternatives to family formation as ways to preserve their loving marriages, satisfy their fatherhood desires, and challenge religious dictates, which they view as out of step with new developments in science and technology. Thus, in this article I examine the complicated intersections of religion, technology, marriage, and parenthood in a part of the world that is both poorly understood and negatively stereotyped, particularly in the aftermath of September 11, 2001. 相似文献