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排序方式: 共有358条查询结果,搜索用时 765 毫秒
71.
子宫异常出血与细菌L型感染的关系   总被引:1,自引:0,他引:1  
通常认为,子宫异常出血由内分泌紊乱、内膜肿瘤和子宫内膜炎引起。通过对471例子宫异常出血内膜组织的细菌学及免疫组化等研究,我们发现绝大多数(85.7%)出血者原因不明,其中376例子宫内膜查见L型菌。本组细菌L型感染率为93.8%。提示子宫异常出血(包括绝经后出血)与细菌L型感染关系也很密切。并认为,子宫内膜细菌L型感染是导致子宫异常出血的重要原因之一。选择作用于细菌胞膜的药物治疗细菌L型感染效果最好。  相似文献   
72.
本文以PNA(花生凝集素)为探针,应用ABC亲和组化技术,对69例原发不育症患者的子宫内膜PNA受体进行了检测.结果表明,原发不育症子宫内膜的增生期、分泌期PNA受体的阳性率均显著低于年龄相似、有生育史的对照组子宫内膜的阳性率.不育症子宫内膜分泌欠佳的PNA受体阳性率显著低于不育症分泌期不同时期子宫内膜的阳性率.提示,这种差异可能与雌孕激素对两组子宫内膜作用水平的不同引起.  相似文献   
73.
Endometriosis: the pathophysiology as an estrogen-dependent disease   总被引:16,自引:0,他引:16  
Endometriosis, defined as the presence of endometrial glands and stroma outside of the uterine cavity, develops mostly in women of reproductive age and regresses after menopause or ovariectomy, suggesting that the growth is estrogen-dependent. Indeed, the lesions contain estrogen receptors (ER) as well as aromatase, an enzyme that catalyses the conversion of androgens to estrogens, suggesting that local estrogen production may stimulate the growth of lesions. The expression patterns of ER and progesterone receptors in endometriotic lesions are different from those in the eutopic endometrium. Moreover, estrogen metabolism, including the expression pattern of aromatase and the regulation of 17β-hydroxysteroid dehydrogenase type 2 (an enzyme responsible for the inactivation of estradiol to estrone), is altered in the eutopic endometrium of women with endometriosis, adenomyosis, and/or leiomyomas compared to that in the eutopic endometrium of women without disease. Immunostaining for P450arom in endometrial biopsy specimens diagnosed these diseases with sensitivity and specificity of 91 and 100%, respectively. This is applicable to the clinical diagnosis of endometriosis. The polymorphisms in the ER- gene, the CYP19 gene encoding aromatase, and several other genes are associated with the risk of endometriosis. Studies of these will lead to better understandings of the etiology and pathophysiology of endometriosis.  相似文献   
74.
七叶树花粉活力和柱头可授性变化的研究   总被引:1,自引:0,他引:1  
李莺  陈鹏涛  樊静静 《广西植物》2012,32(6):816-821
采用花粉离体萌发法研究不同蔗糖浓度、硼酸浓度和不同温度对七叶树花粉萌发的影响及花粉活力测定,用联苯胺-过氧化氢法测定柱头可授性.结果表明:七叶树花粉萌发的最佳培养基是12%蔗糖+30 mg/L硼酸,花粉萌发的最适温度为25℃.雄花在开花当天花粉活力最高达75.69%,并在开花当天的上午10:00时,花粉活力最强,10:00~16:00花粉活力保持较高活力,是最佳授粉时段.两性花的柱头可授期持续时间较长,为8~9 d,开花3d达到最强,开花1~4 d柱头可授性保持较高水平,为授粉的最佳时间段.因此,从七叶树的花部特征、花粉活力与柱头可授性及花粉萌发的条件看,在长期的自然选择下七叶树在花部结构和开花生理上都是相配合的,以保障生殖成功.  相似文献   
75.
Endometriosis is a common condition in reproductive-aged women characterized by ectopic endometrial lesions of varied appearance, including red, white, blue, black or powder burn coloration, which contribute to chronic pain and infertility. The immunoconjugate molecule (Icon) targets Tissue Factor, a transmembrane receptor for Factor VII/VIIa that is aberrantly expressed in the endothelium supporting ectopic endometrial tissue. Icon has been shown to cause regression of endometriosis in a murine model of disease but prior to this study had not been tested in non-human primates. This study evaluated Icon as a novel treatment for endometriosis in non-human primates (Papio anubis) using an adenoviral vector (AdIcon) delivery system. Female baboons (n?=?15) underwent surgical induction of endometriosis. After laparoscopic confirmation of endometriosis lesions 6-weeks post-surgery, the treatment group (n?=?7) received weekly intraperitoneal injections of viral particles carrying the sequence for Icon, resulting in expression of the protein, while the control group (n?=?8) received no treatment. Icon preferentially reduced the number and volume of red vascularized lesions. Icon may present a novel treatment for endometriosis by degrading red vascularized lesions, likely by targeting tissue factor aberrantly expressed in the lesion vasculature.  相似文献   
76.
Extracellular lysophosphatidic acid (LPA) and the G-protein-coupled LPA receptors (LPAR) are involved in cell migration and invasion and found in the human endometrium. However, underlying mechanisms resulting in cellular invasion have been rarely investigated. We used stromal endometrial T-HESC, epithelial endometriotic 12Z, 49Z and Ishikawa cells. Interestingly, proliferation of T-HESC cells was strongly increased after LPA treatment, whereas the epithelial cell lines only showed a moderate increase. LPA increased invasion of 12Z and 49Z strongly and significantly. The LPAR inhibitor Ki16425 (LPAR1/3) attenuated significantly LPA-induced invasiveness of 12Z, which was confirmed by LPAR1 and LPAR3 siRNAs, showing that both LPA receptors contribute to invasiveness of 12Z cells. Investigation of cell invasion with an antibody-based protease array revealed mainly differences in cathepsins and especially cathepsin B between 12Z compared to the less invasive Ishikawa. Stimulation with LPA showed a time- and dose-dependent increased secretion of cathepsin B which was inhibited by the Gq inhibitor YM-254890 and Gi/o inhibitor pertussis toxin in the 12Z cells, again highlighting the importance of LPAR1/3. The activity of intracellular and secreted cathepsin B was significantly upregulated in LPA-treated samples. Inhibition of cathepsin B with the specific inhibitor CA074 significantly reduced LPA-increased invasion of 12Z. Our results reveal a novel role of LPA-mediated secretion of cathepsin B which stimulated invasion of endometriotic epithelial cells mainly via LPAR1 and LPAR3. These findings may deepen our understanding how endometriotic cells invade into ectopic sites, and provide new insights into the role of LPA and cathepsin B in cellular invasion.  相似文献   
77.
In field populations, several male jewel spidersGasteracantha minax Thorell (Araneidae) may be found at the periphery of the orb web of a female, indicating that males may compete for fertilisation success. Laboratory experiments revealed that virgin femaleG. minax readily remate shortly after their first mating. However, they appear to enter a refractory period between 1 and 24 h postmating and respond aggressively to courting males. Males that have mated with a female initially defend her from rival males but cease to do so after the onset of the refractory period. These data can be interpreted within the context of mate-guarding and sperm competition. There is marked size dimorphism in this species, which may be the result of selection for protandry. In contrast with other orb-weaving spiders, this selection pressure does not seem to be counterbalanced by selection for larger male size through either sexual cannibalism or male-male competition.  相似文献   
78.
《Theriogenology》2016,86(9):1635-1643
In this study, we investigated the expression of mucin 1 (MUC1) mRNA and protein in sheep endometrium at different time points during follicular and luteal phases of estrous cycle, and also determined the effect of steroid hormone treatments and interferon tau (IFNτ) on MUC1 mRNA expression in endometrial cell culture in vitro. In experiment one, 15 Welsh mountain ewes were synchronized to a common estrus and killed at precise stages of estrous cycle corresponding to (1) pre-LH peak, (2) LH peak, (3) post-LH peak, (4) early luteal, and (5) mid-luteal. Reproductive tracts were harvested and mRNA was extracted from the endometrial tissues. Parts of the uterine horns were fixed for immunohistochemistry. In experiment two, mixed populations of ovine endometrial cells (from slaughterhouse material collected at the postovulatory stage of the estrous cycle) were cultured to 70% confluence before treatment with (1) progesterone (P4, 10 ng/mL, for 48 hours), (2) estradiol (E2, 100 pg/mL, for 48 hours), or with (3) E2 priming for 12 hours (100 pg/mL) followed by P4 (10 ng/mL) for 36 hours. These were compared with: (4) IFNτ (10 ng/mL, for 48 hours), and (5) basic medium (Dulbecco Modified Eagle Medium /F12) as control. The results showed that MUC1 mRNA and protein expression in sheep endometrium were highest during the midluteal stage and very low during the post-LH period compared with the other stages (P < 0.05). MUC1 immunostaining in the luminal epithelium was apically restricted and was not significantly different across all stages of estrous cycle except at the post-LH peak where it was significantly low. In cell culture, MUC1 mRNA expression was significantly upregulated by both steroids either singly or in combination (P < 0.05), and downregulated in the presence of IFNτ. In conclusion, endometrial MUC1 expression is cyclically regulated by both E2 and P4 in vivo and in vitro, and directly downregulated by IFNτ treatment in vitro.  相似文献   
79.
Summary Three types of transendothelial channels are described in the endothelium of blood capillaries in the endometrium of the rat. It is postulated that they may function as pores draining interstitial fluid to the venous blood.Supported by a grant from the Nationaal Fonds voor Wetenschappelijk Onderzoek — Fonds voor Geneeskundig Wetenschappelijk Onderzoek (Belgium)  相似文献   
80.
Glycosylation alters the molecular and functional features of glycoproteins, which is closely related with many physiological processes and diseases. During “window of implantation”, uterine endometrium transforms into a receptive status to accept the embryo, thereby establishing successful embryo implantation. In this article, we aimed at investigating the role of N-glycosylation, a major modification type of glycoproteins, in the process of endometrial receptivity establishment. Results found that human uterine endometrial tissues at mid-secretory phase exhibited Lectin PHA-E+L (recognizes the branched N-glycans) positive N-glycans as measured by the Lectin fluorescent staining analysis. By utilizing in vitro implantation model, we found that de-N-glycosylation of human endometrial Ishikawa and RL95-2 cells by tunicamycin (inhibitor of N-glycosylation) and peptide-N-glycosidase F (PNGase F) impaired their receptive ability to human trophoblastic JAR cells. Meanwhile, N-glycosylation of integrin αvβ3 and leukemia inhibitory factor receptor (LIFR) are found to play key roles in regulating the ECM-dependent FAK/Paxillin and LIF-induced STAT3 signaling pathways, respectively, thus affecting the receptive potentials of endometrial cells. Furthermore, in vivo experiments and primary mouse endometrial cells-embryos coculture model further verified that N-glycosylation of mouse endometrial cells contributed to the successful implantation. Our results provide new evidence to show that N-glycosylation of uterine endometrium is essential for maintaining the receptive functions, which gives a better understanding of the glycobiology of implantation.  相似文献   
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