首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Although the adverse effects of maternal aging on reproductive outcomes have been investigated widely, there is no consensus on the impact of paternal age. Therefore, we investigated the effect of paternal age on reproductive outcomes in a retrospective analysis of 9,991 in vitro fertilization (IVF) cycles performed at the Reproductive Medicine Center of the Third Affiliated Hospital of Guangzhou Medical University (China) between January 2007 and October 2013. Samples were grouped according to maternal age [<30 (3,327 cycles), 30–34 (4,587 cycles), and 35–38 (2,077 cycles)] and then subgrouped according to paternal age (<30, 30–32, 33–35, 36–38, 39–41, and ≥42). The groups did not differ in terms of fertilization rate, numbers of viable and high-quality embryos and miscarriage rate when controlling maternal age (P >0.05). Chi-squared analysis revealed that there were no differences in implantation and pregnancy rates among the different paternal age groups when maternal age was <30 and 35–38 years (P >0.05). However, implantation and pregnancy rates decreased with paternal age in the 31–34 y maternal age group (P <0.05). Our study indicates that paternal age has no impact on fertilization rate, embryo quality at the cleavage stage and miscarriage rate. For the 30–34 y maternal age group, the implantation rate decreased with increased paternal age, with the pregnancy rate in this group being significantly higher in the paternal <30 y and 30–32 y age groups, compared with those in the 36–38 y and 39–41 y groups.  相似文献   

2.
3.
小鼠卵母细胞体外成熟、体外受精的效果观察   总被引:2,自引:0,他引:2  
目的 研究不同培养条件对小鼠卵母细胞体外成熟及体外受精率的影响。方法 小鼠卵母细胞分别在含有FSH、BSA和胰岛素的培养液中体外成熟,在Whitten 氏液中体外受精,比较体外成熟率、体外受精率。结果 1- 裸卵(DO) 的体外成熟率、体外受精率(81-4% ,31-0 % ) 均高于卵丘卵母细胞复合体(COC)(48-6 % ,27-1% ) 。2- 在培养液中添加FSH、胰岛素和BSA,卵母细胞的体外成熟率为77-9 % ,82-3% 、60-7% ;体外受精率为77-2 % 、72-6 % 、26-7% ;2 - 细胞率为49-2 % 、34-2 % 、10-0% 。胰岛素组的卵母细胞IVM 率最高,但IVF率、2 - 细胞率低于FSH 组。3- 添加BSA的两组的体外受精率只有26-7 % 、25-8 % ,显著低于其他组,其体外成熟率也较添加FSH 和胰岛素的组成。4- 排出第一极体(PbI) 的卵母细胞的体外受精率和2 - 细胞率(85-9 % ,22-4% ) 均高于GV期卵母细胞(71-1 % ,12-9 % ) 。结论 1- 卵丘卵母细胞(COC) 较裸卵(DO) 的体外成熟率、体外受精率都低,差异显著(P成熟< 0-01;P受精< 0-05) 。2-FSH 和胰岛素均能提高小鼠卵母细胞的体外成熟率、体外受精率。3-BSA可以降低小鼠卵母细胞体外受精率,差异极显著。4-GV 期卵母细胞的体外受精率显著低于体外培养的排出第一极体的卵母细胞(P2 - cell < 0-05,P受精<0-05)  相似文献   

4.
猪卵母细胞的体外受精及多精受精   总被引:4,自引:0,他引:4  
对用于猪体外受精(IVF)的研究方法和技术,如传统的液滴IVF、透明带下注射精子受精(SUZI)、卵母细胞质内单精注射受精(ICSI)及细管IVF等进行了简述。与其它动物相比,进行猪卵的体外受精研究,多精受精现象特别明显。大量的研究表明,猪卵的多精受精不但与其品种特性有关,而且与卵母细胞成熟的程度、透明带的异常、受精时获能精子的浓度、输卵管分泌物、受精液蛋白添加成分、NaHCO3浓度、咖啡因、pH值以及温度等因素密切相关。  相似文献   

5.
牛卵母细胞体外受精及体外发育的研究   总被引:3,自引:0,他引:3  
本研究利用从屠宰场收集到的牛卵巢,获取卵母细胞,经体外成熟后进行体外受精,其受精率为73±2%。受精卵分别用发育培养基TCM—199+10%FCS(MA)、颗粒细胞单层(MB)和卵管上皮单层(MC)进行培养,其8—16细胞的发育率分别为52%、54%和61%;而囊胚的发育率分别为20%、28%和42%。相比较而言,MB和MC培养基内突破8—16细胞阻断发育到囊胚的发育率优于MA。  相似文献   

6.
Parental care is widespread among animals and many studies have investigated how environmental conditions influence parental care strategies. However, few studies have coupled observations of the frequency and form of parental care with manipulative studies on the function of care across multiple seasons. To address this gap, we made field observations and conducted male removal experiments in a glass frog with paternal egg attendance from the island of Tobago, West Indies. To test the hypothesis that seasonality impacts the frequency, form, and function of parental care, field observations and male removal experiments were undertaken three times, twice during the rainy season, and once in the dry season. We found seasonal differences in the frequency of egg attendance with males increasing the frequency of this behavior in the dry season, likely in response to a greater risk of clutch desiccation. We also found that clutches in which the male was removed had strongly reduced survivorship compared with controls and this pattern did not change seasonally. However, sources of mortality were strongly influenced by season. Arthropod predation was the primary source of mortality during the wet season, but in the dry season, desiccation was more important. Together, these results suggest that seasonal variation is both impacting care function as well as shaping the form that parental care takes.  相似文献   

7.
我国被子植物体外受精研究—十年回顾   总被引:3,自引:1,他引:3  
简要回顾了十余年来我国被子植物体外受精领域的研究历程和主要成就。我国科学家在性细胞的分离 ,尤其是生活胚囊和雌配子的分离方面走在国际前列。在一定程度上我国科学家的开拓性工作引起了国际同行的广泛兴趣和重视 ,推动了该领域的迅速发展 ,为实现被子植物真正意义的体外受精做出了独特的贡献。十年来 ,我国已建立了自己独特的被子植物离体受精实验技术系统并利用该系统与国际同行合作进行了一系列研究 ,尤其在探讨配子相互作用、卵细胞激活、避免多精入卵的机制等方面做出了创新性工作 ,为正确认识体外受精系统的优越性与局限性 ,也为深入探讨受精机制提供了有价值的新资料。目前正以体外受精操作系统结合细胞生物学和分子生物学等多种手段对受精过程中的一些重要事态与机理做进一步探讨  相似文献   

8.
简要回顾了十余年来我国被子植物体外受精领域的研究历程和主要成就.我国科学家在性细胞的分离, 尤其是生活胚囊和雌配子的分离方面走在国际前列. 在一定程度上我国科学家的开拓性工作引起了国际同行的广泛兴趣和重视, 推动了该领域的迅速发展, 为实现被子植物真正意义的体外受精做出了独特的贡献.十年来, 我国已建立了自己独特的被子植物离体受精实验技术系统并利用该系统与国际同行合作进行了一系列研究, 尤其在探讨配子相互作用、卵细胞激活、避免多精入卵的机制等方面做出了创新性工作, 为正确认识体外受精系统的优越性与局限性, 也为深入探讨受精机制提供了有价值的新资料.目前正以体外受精操作系统结合细胞生物学和分子生物学等多种手段对受精过程中的一些重要事态与机理做进一步探讨.  相似文献   

9.
It has been hypothesized that in maternal mouthbrooding cichlids the conspicuous markings on the male's anal fin function as “egg-dummies” by fooling the female into snapping at them, thereby inhaling sperm and assuring fertilization of the eggs in the mouth. I show experimentally in Pseudocrenilabrus multicolor, an East African maternal mouthbrooder, that indeed oral fertilization takes place. Nevertheless, external fertilization plays a significant role, too.  相似文献   

10.
11.
Solitary male and female Texas cichlids, Cichlasoma cyanoguttatum employ different tactics when defending their offspring. Males emphasize the lateral display against an intruder and make infrequent return visits to the young while the intruder is present. The female is more likely to attack, attempting to bite the intruder and also making frequent return visits to the offspring. These differences disappear with increasing age of the offspring as the male becomes more like the female with more violent attacks. Both defense systems appear effective, in the short term, against intruders.  相似文献   

12.
13.
Kranz E  Lorz H 《The Plant cell》1993,5(7):739-746
We demonstrate here the possibility of regenerating phenotypically normal, fertile maize plants via in vitro fertilization of isolated, single sperm and egg cells mediated by electrofusion. The technique leads to the highly efficient formation of polar zygotes, globular structures, proembryos, and transition-phase embryos and to the formation of plants from individually cultured fusion products. Regeneration of plants occurs via embryogenesis and occasionally by polyembryony and organogenesis. Flowering plants can be obtained within 100 days of gamete fusion. Regenerated plants were studied by karyological and morphological analyses, and the segregation of kernel color was determined. The hybrid nature of the plants was confirmed.  相似文献   

14.
15.
During the colonization of hosts, bacterial pathogens are presented with many challenges that must be overcome for colonization to occur successfully. This requires the bacterial sensing of the surroundings and adaptation to the conditions encountered. One of the major impediments to the pathogen colonization of the mammalian gastrointestinal tract is the antibacterial action of bile. Salmonella enterica serovar Typhimurium has specific mechanisms involved in resistance to bile. Additionally, Salmonella can successfully multiply in bile, using it as a source of nutrients. This accomplishment is highly relevant to pathogenesis, as Salmonella colonizes the gallbladder of hosts, where it can be carried asymptomatically and promote further host spread and transmission. To gain insights into the mechanisms used by Salmonella to grow in bile, we studied the changes elicited by Salmonella in the chemical composition of bile during growth in vitro and in vivo through a metabolomics approach. Our data suggest that phospholipids are an important source of carbon and energy for Salmonella during growth in the laboratory as well as during gallbladder infections of mice. Further studies in this area will generate a better understanding of how Salmonella exploits this generally hostile environment for its own benefit.  相似文献   

16.
The effects of different media and cultural methods on cotton pollen germination were compared. Pollen germination was successful on the improved Taylor solid medium in which the extracts of the stigmata and petals of the original species, and the comprehensive amino acids were added, respectively. The germinating pollens were viable, and active protoplasmic streaming was observed within the pollen tube. It was found that low temperature pretreatment could increase the pollen germination rate. The reasons that low temperature pretreatment stimulated pollen germination and castor oil caused abortive germination of cotton pollens were discussed. In vitro fertilization between two species of Gossypium can be promoted by smearing the stigmata with the improved Taylor medium.  相似文献   

17.
Nitric oxide (NO) is a molecule involved in many reproductive processes. Its importance during oocyte in vitro maturation (IVM) has been demonstrated in various species although sometimes with contradictory results. The objective of this study was to determine the effect of NO during IVM of cumulus oocyte complexes and its subsequent impact on gamete interaction in porcine species. For this purpose, IVM media were supplemented with three NOS inhibitors: NG-nitro-L-arginine methyl ester (L-NAME), NG-monomethyl-L-arginine (L-NMMA) and aminoguanidine (AG). A NO donor, S-nitrosoglutathione (GSNO), was also used. The effects on the cumulus cell expansion, meiotic resumption, zona pellucida digestion time (ZPdt) and, finally, on in vitro fertilization (IVF) parameters were evaluated. The oocyte S-nitrosoproteins were also studied by in situ nitrosylation. The results showed that after 42 h of IVM, AG, L-NAME and L-NMMA had an inhibitory effect on cumulus cell expansion. Meiotic resumption was suppressed only when AG was added, with 78.7% of the oocytes arrested at the germinal vesicle state (P<0.05). Supplementation of the IVM medium with NOS inhibitors or NO donor did not enhance the efficiency of IVF, but revealed the importance of NO in maturation and subsequent fertilization. Furthermore, protein S-nitrosylation is reported for the first time as a pathway through which NO exerts its effect on porcine IVM; therefore, it would be important to determine which proteins are nitrosylated in the oocyte and their functions, in order to throw light on the mechanism of action of NO in oocyte maturation and subsequent fertilization.  相似文献   

18.
The theoretical underpinnings of the mechanisms of sociality, e.g. territoriality, hierarchy, and reciprocity, are based on assumptions of individual recognition. While behavioural evidence suggests individual recognition is widespread, the cues that animals use to recognise individuals are established in only a handful of systems. Here, we use digital models to demonstrate that facial features are the visual cue used for individual recognition in the social fish Neolamprologus pulcher. Focal fish were exposed to digital images showing four different combinations of familiar and unfamiliar face and body colorations. Focal fish attended to digital models with unfamiliar faces longer and from a further distance to the model than to models with familiar faces. These results strongly suggest that fish can distinguish individuals accurately using facial colour patterns. Our observations also suggest that fish are able to rapidly (≤ 0.5 sec) discriminate between familiar and unfamiliar individuals, a speed of recognition comparable to primates including humans.  相似文献   

19.
This study investigated the risk factors and early predictors for heterotopic pregnancy (HP) after in vitro fertilization and embryo transfer (IVF-ET). From January 2008 to January 2013, 41 cases of HP and 72 cases of intrauterine twin pregnancy after IVF-ET were recruited and retrospectively analyzed. Compared with intrauterine twin pregnancy group, the HP group had a lower basal luteinizing hormone (LH) level (P = 0.005) and more cases had a history of hydrosalpinx (P = 0.008). After 14 days of IVF-ET, the serum β-HCG (β-human chorionic gonadotropin), E2 (Estradiol) and P (Progesterone) levels were lower in HP group (P<0.001, respectively). Moreover, vaginal bleeding and abdominal pain were the significant features of HP before diagnosis (P<0.001, respectively). Further by logistic regression, serum β-hCG, P levels on the 14th day after ET, and vaginal bleeding were identified as the independent factors of HP. These results indicate that when two or more embryos transferred in IVF procedure, β-hCG, P levels on the 14th day after ET, and vaginal bleeding could be taken as predictors for HP.  相似文献   

20.
Abstract Cecropins and other natural antimicrobial peptides are widely distributed in animals from insects to mammals. These proteins have been shown to be major constituents of the innate immune systems of animals for nonspecific defense of the host against various bacteria and parasites. Therefore, exploitation of this natural innate defense system may lead to the development of effective methods for protecting fish from invasion by microbial pathogens. Recently, we have demonstrated that the introduction of cecropin transgenes into Japanese medaka (Oryzias latipes) conferred resistance to infection by fish bacterial pathogens. Aside from a few reports documenting the antiviral effect of antimicrobial peptides including cecropins against mammalian viruses, there is no evidence for the effect of these peptides against fish viruses. In this article we present results of in vitro characterization of native cecropin B and a synthetic analogue, CF17, against several important fish viral pathogens—namely, infectious hematopoietic necrosis virus (IHNV), viral hemorrhagic septicemia virus (VHSV), snakehead rhabdovirus (SHRV), and infectious pancreatic necrosis virus (IPNV). Upon coincubation of these peptides and viruses, the viral titers yielded in fish cells were reduced from several fold to 104-fold. Direct disruption of the viral envelope and disintegration of the viral capsids may be involved in the inhibition of viral replication by the peptides. Results of our studies demonstrate the potential of manipulating antimicrobial peptide genes by transgenesis to combat viral infection in fish.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号