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11.
人卵丘细胞与卵母细胞发育及成熟的关系 总被引:1,自引:0,他引:1
卵丘细胞与卵母细胞共处于同一个卵泡液微环境中,卵丘细胞与卵母细胞之间复杂的"对话机制"调控着卵母细胞的成熟和卵丘细胞的增殖延伸。在窦卵泡阶段,卵丘细胞由颗粒细胞分化而来,通过缝隙连接与卵母细胞共同形成一个结构和功能上的合胞体。卵泡发育不同时期,卵丘细胞对卵母细胞的代谢调控主要表现为:在窦卵泡期,卵丘细胞为卵母细胞发育提供必需的营养,而卵母细胞分泌的信号因子亦调控着卵丘细胞的增殖和延伸;在排卵前卵泡中,卵丘细胞主要通过调控卵母细胞中cAMP水平,促使卵母细胞恢复减数分裂;在排卵后卵泡中,卵丘细胞亦影响着精-卵结合及胚胎发育的过程。另外,伴随卵泡内微环境的变化,卵丘细胞与卵母细胞间发生着复杂的信号传递,从而对卵母细胞的发育实现分子水平的调控,其中部分基因可能作为卵母细胞发育成熟、胚胎发育及妊娠结局的分子标志物。 相似文献
12.
Ning Zhang Cuifang Hao Xiaoyan Liu Shouxin Zhang Fengrong Zhang Lili Zhuang 《Gynecological endocrinology》2017,33(2):113-118
Objective: To identify the quantitative profiling of adiponectin and its receptors (AdipoR1, AdipoR2, and T-cadherin) in cumulus cells (CCs) and to evaluate their roles in the early embryo development of polycystic ovary syndrome (PCOS) patients, in part, with obesity.Methods: Fifty-five subjects were divided into two groups according to the body mass index. Oocytes were further inseminated and only mature and normal fertilized oocytes (2PN) were included in this research. Real-time PCR and western blot were performed to identify adiponectin and its receptors in CCs.Results: Adiponectin and receptors were ubiquitously expressed in CCs of PCOS and non-PCOS patients. The level of AdipoR2 in CCs from the oocytes yielding blastocyst after 5/6 days in vitro culture was markedly higher than in those from oocytes could not develop to blastocyst stage after Day 6, for non-obese or obese PCOS patients (0.1647?±?0.0161 versus 0.0783?±?0.0385, 0.1948?±?0.0307 versus 0.1057?±?0.0236, respectively, p?0.05). In addition, only in patients with PCOS and concurrent obesity the AdipoR1 in CCs was considerably increased in CC-B+ compared with CC-B? subgroup (0.5162?±?0.0371 versus 0.2448?±?0.0333, p?0.01).Conclusion: The development of early embryo was associated with the up-regulation of AdipoR1 and AdipoR2 in PCOS patients. Our results suggested that adiponectin could positively modulate embryo development in humans. Further investigations should be carried out to unlock the crucial role that adiponectin plays in embryo development. 相似文献
13.
目的:研究人卵巢颗粒细胞叉头框(forkhead box,Fox)基因和卵泡刺激素受体(follicle stimulating hormone receptor,FSHR)的表达及相关性。方法接受体外受精-胚胎移植(in vitro fertilization-embryo transfer, IVF-ET)不孕症患者126例,按照妊娠结果分为妊娠组63例,未妊娠组63例。回顾性分析取卵日成熟卵泡壁颗粒细胞 FoxO1、FoxO3a 和 FSHR mRNA 的表达,并对 FoxO1、FoxO3a、FSHR 之间及与血清促黄体生成素(luteotropic hormone,LH)、雌二醇(estradiol,E2)、孕酮(progesterone,P)进行相关性分析。结果妊娠组血清 E2水平高于未妊娠组(P<0.01);妊娠组优质胚胎数多于未妊娠组(P<0.01);2组 LH、P、获卵数差异无统计学意义(P>0.05)。妊娠组 FoxO1 mRNA表达高于未妊娠组(P<0.01);2组 FoxO3a及 FSHR mRNA差异无统计学意义(P>0.05)。FoxO1和 FoxO3a与FSHR的相关性系数分别为0.881、0.999(P<0.01i)。结论 FoxO1和FoxO3a参与卵母细胞质量的调节,其功能与 FSHR有密切关系。 相似文献
14.
The continuing quest for cost-effective and complex shaped aluminum castings with fewer defects for applications in the automotive industries has aroused the interest in rheological high pressure die casting (R-HPDC). A new machine, forced convection mixing (FCM) device, based on the mechanical stirring and convection mixing theory for the preparation of semisolid slurry in convenience and functionality was proposed to produce the automotive shock absorber part by R-HPDC process. The effect of barrel temperature and rotational speed of the device on the grain size and morphology of semi-solid slurry were extensively studied. In addition, flow behavior and temperature field of the melt in the FCM process was investigated combining computational fluid dynamics simulation. The results indicate that the microstructure and pore defects at different locations of R-HPDC casting have been greatly improved. The vigorous fluid convection in FCM process has changed the temperature field and composition distribution of conventional solidification. Appropriately increasing the rotational speed can lead to a uniform temperature filed sooner. The lower barrel temperature leads to a larger uniform degree of supercooling of the melt that benefits the promotion of nucleation rate. Both of them contribute to the decrease of the grain size and the roundness of grain morphology. 相似文献
15.
16.
为了了解矩形腔内非Boussinesq流体自然对流换热的特有现象和规律,利用有限容积法对矩形腔内的冷水自然对流进行了一系列数值模拟,得到了不同宽深比、Rayleigh数下的流场和温度场,并对不同条件下的壁面传热特性进行了比较与分析。计算结果表明:随着宽深比的增大,流动逐渐增强,流胞数逐渐增多,壁面平均Nusselt数逐渐增大,并趋于某一定值;随着Rayleigh数的增加,换热能力也会增强,而且流动结构的转变会在更小的宽深比下发生。采用逐步线性回归方法,得到了关于热壁平均Nusselt数的传热关联式。 相似文献
17.
目的:探讨降钙素基因相关肽(calcitonin gene-related peptide, CGRP) 对小鼠卵母细胞体外成熟的影响。方法:6 周龄雌性昆明小鼠腹腔注射孕马血清促性腺激素(pregnant mare serum gonadotropin, PMSG)10 U 48 h 后处死, 取出卵巢收集卵母细胞以30~40 枚/ 孔的密度接种于培养板内, 以不同浓度CGRP(0, 10-10, 10-9, 10-8 mol/L) 处理24 h后检测生发泡破裂(germinal vesicle breakdown, GVBD) 率和第一极体(polarbody I, PBI) 排出率;收集、培养人卵巢颗粒细胞, 以不同浓度CGRP(0, 10-10, 10-9, 10-8 mol/L) 处理24 h 后测定颗粒细胞内cAMP 浓度。结果:外源性CGRP处理小鼠卵母细胞可浓度依赖性地降低GVBD 率及PBI 排出率;外源性CGRP 处理人颗粒细胞, 可浓度依赖性地增高细胞内cAMP 浓度。结论:CGRP 抑制小鼠卵母细胞成熟可能与其增加颗粒细胞内cAMP 浓度有关。 相似文献
18.
Natural Convection Heat Transfer in a Porous Cavity with Sinusoidal Temperature Distribution Using Cu/Water Nanofluid: Double MRT Lattice Boltzmann Method 下载免费PDF全文
Hasan Sajjadi Amin Amiri Delouei Rasul Mohebbi Mohsen Izadi & Sauro Succi 《Communications In Computational Physics》2021,29(1):292-318
In this study, natural convection flow in a porous cavity with sinusoidal
temperature distribution has been analyzed by a new double multi relaxation time
(MRT) Lattice Boltzmann method (LBM). We consider a copper/water nanofluid filling a porous cavity. For simulating the temperature and flow fields, D2Q5 and D2Q9
lattices are utilized respectively, and the effects of different Darcy numbers (Da) (0.001-0.1) and various Rayleigh numbers (Ra) ($10^3$-$10^5$) for porosity ($ε$) between 0.4 and 0.9
have been considered. Phase deviation ($θ$) changed from 0 to $π$ and the volume fraction
of nanoparticles (Ø) varied from 0 to 6%. The present results show a good agreement
with the previous works, thus confirming the reliability the new numerical method
proposed in this paper. It is indicated that the heat transfer rate increases at increasing
Darcy number, porosity, Rayleigh number, the volume fraction of nanoparticles and
phase deviation. However, the most sensitive parameter is the Rayleigh number. The
maximum Nusselt deviation is 10%, 32% and 33% for Ra=$10^3$, $10^4$ and $10^5$, respectively, with $ε = 0.4$ to $ε = 0.9$. It can be concluded that the effect of Darcy number on
the heat transfer rate increases at increasing Rayleigh number, yielding a maximum
enhancement of the average Nusselt number around 12% and 61% for Ra=$10^3$ and
Ra=$10^5$, respectively. 相似文献
19.
Effect of cumulus cell mass and follicle quality on in-vitro maturation of cynomolgus monkey oocytes
Lefevre Brigitte; Gougeon A.; Peronny Huguette; Testart J. 《Human reproduction (Oxford, England)》1988,3(7):891-893
Cynomolgus monkey oocytes were recovered from healthy or atreticfollicles > 1000 µm in diameter at day 8 of gonadotrophinstimulated cycles and cultured in vitro, cumulus enclosed orcumulus free, for 2 days. Germinal vesicle breakdown (GVBD)occurred in 26.7% of healthy cumulus enclosed oocytes (n= 60)compared to 52.6% of atretic cumulus enclosed oocytes (n = 38).The mechanical removal of the cumulus cell mass increased theGVBD rate of the healthy oocytes (56.5%, n = 23) and acceleratedthe passage of the atretic oocytes (n = 23) from metaphase I(4.3%) to metaphase II (47.8%). In the healthy primate follicle,the dktyate stage could be maintained by aninhibitory substancesecreted by the cumulus; foUicular atresia could either decreasethe synthesis of this substance and/or induce the metabolismof a stimulatory substance. 相似文献
20.
Human sperm chemotaxis: both the oocyte and its surrounding cumulus cells secrete sperm chemoattractants 总被引:5,自引:0,他引:5
Sun F Bahat A Gakamsky A Girsh E Katz N Giojalas LC Tur-Kaspa I Eisenbach M 《Human reproduction (Oxford, England)》2005,20(3):761-767
BACKGROUND: Human sperm chemotaxis to pre-ovulatory follicular fluid is well established in vitro. However, it is not known whether the female's oocyte-cumulus complex secretes sperm chemoattractants subsequent to ovulation (for enabling sperm chemotaxis within the Fallopian tube) and, if so, which of these cell types--the oocyte or the cumulus oophorus--is the physiological origin of the secreted chemoattractant. METHODS: By employing a directionality-based chemotaxis assay, we examined whether media conditioned with either individual, mature (metaphase II) human oocytes or the surrounding cumulus cells attract human sperm by chemotaxis. RESULTS: We observed sperm chemotaxis to each of these media, suggesting that both the oocyte and the cumulus cells secrete sperm chemoattractants. CONCLUSIONS: These observations suggest that sperm chemoattractants are secreted not only prior to ovulation within the follicle, as earlier studies have demonstrated, but also after oocyte maturation outside the follicle, and that there are two chemoattractant origins: the mature oocyte and the surrounding cumulus cells. 相似文献