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1.
In vitro binding affinities of various progestins to cytosol and nuclear progesterone receptors of rabbit uterus were determined and correlated with the biological potency of these steroids. In addition, cytosol and nuclear progesterone receptor levels were measured after a 5-day administration of different progestins (0.5 mg/kg daily) with variable biologic activites. The receptor levels were compared with the bilological response; the induction of uteroglobin synthesis. Cytosol and nuclear progesterone receptors had identical steroid binding properties (r = 0.98). The correlation between the in vitro binding affinity (cytosol or nuclear) and the in vivo biologic activity of the steroids was good (r = 0.73). After a 5-day treatment with progestins, the nuclear receptor concentration correlated in an inverse manner (r = ?0.84) with the uterine fluid unteroglobin concentration. A similar, but slightly weaker correlation (r = ?0.81) was also found for the cytosol receptor content and uteroglobin secretion. These data indicate that not only nuclear, but also cytosol progesterone receptor levels decrease in the rabbit uterus during chronic hormone action. Decline in the nuclear progesterone receptor content seemed to occur during treatment with all progestational steroids, while onlyi progestins with high biological potency were capable of decreasing the cytosol receptor content.  相似文献   
2.
The interaction of estrogen with its receptor from rabbit uterus was studied using the affinity labeling technique. An affinity labeling reagent, 3-hydroxy-17β-(p-nitrophenyldithio)-1,3,5(10)-estratriene (Reagent A) was synthesized. The compound was designed to meet two requirements: (1) it binds specifically to the steroid-binding site of the receptor; (2) it has functional group capable of forming a covalent bond with an amino acid residue at or near the binding site. The first requirement was demonstrated by competitive binding assay and sedimentation analysis. If the binding affinity of 17β-estradiol is defined as 100, that of Reagent A is found to be 0.05. It was shown that the binding was specific for the estradiol receptor. The second requirement was examined by extraction of Reagent A with simple model compounds. 10 μM Reagent A gave rise to approx. 1.3 μM p-nitrothiophenol in the presence of a large excess of l-cysteine or reduced l-glutathione under the experimental conditions employed, indicating that a covalent bond was formed between Reagent A and the model compounds. Furthermore, I have presented evidence by using polyacrylamide gel electrophoresis that 3H-labeled Reagent A is linked covalently to the estrogen-binding site on the receptor of rabbit uterus. The experiment also fulfilled the first requirement. These results indicate that the thiol group present at the binding site is directly involved in the estradiol-receptor binding.  相似文献   
3.
目的:探讨宫腔镜手术对子宫黏膜下肌瘤患者卵巢功能、免疫功能及炎症因子水平的影响。方法:选取2017年1月~2018年4月期间我院收治的子宫黏膜下肌瘤患者107例为研究对象。根据不同的手术治疗方式将患者分为腹腔镜组(n=55,行腹腔镜子宫肌瘤切除术)和宫腔镜组(n=52,行宫腔镜子宫肌瘤切除术),比较两组患者围术期指标;比较两组术前、术后3个月卵巢功能[促卵泡生长素(FSH)、雌二醇(E2)、黄体生成素(LH)、窦卵泡数量(AFC)]、细胞免疫指标(CD3+、CD4+、CD8+)、体液免疫指标(Ig G、Ig A、Ig M)水平;比较两组术前、术后7 d炎症因子[白介素-2(IL-2)、白介素-6(IL-6)、C反应蛋白(CRP)]指标水平;记录两组术后并发症发生情况。结果:两组患者手术时间、术中出血量比较差异无统计学意义(P0.05);宫腔镜组术后下床时间、肛门排气时间、住院时间以及抗生素使用时间均短于腹腔镜组(P0.05)。两组患者术后3个月E2、LH、AFC比较差异无统计学意义(P0.05);腹腔镜组术后3个月FSH水平高于术前及宫腔镜组(P0.05)。腹腔镜组患者术后3个月细胞免疫指标低于术前及宫腔镜组(P0.05),但体液免疫指标与术前比较差异无统计学意义(P0.05);宫腔镜组术后3个月各项免疫指标与术前比较差异无统计学意义(P0.05)。两组患者术后7d IL-2、IL-6以及CRP水平均升高,但宫腔镜组低于腹腔镜组(P0.05)。腹腔镜组术后并发症发生率为10.91%(6/55),与宫腔镜组的9.62%(5/52)比较差异无统计学意义(P0.05)。结论:宫腔镜子宫肌瘤切除术对子宫黏膜下肌瘤患者卵巢功能、免疫功能影响较轻,同时可降低炎性因子水平,未出现严重并发症,具有一定的临床应用价值。  相似文献   
4.
目的:探究阴式子宫全切除术与腹腔镜辅助下阴式子宫切除术治疗子宫良性病变的临床效果。方法:选择2011年10月~2013年9月我院收治的子宫良性病变的患者120例,其中行腹腔镜辅助下阴式子宫切除术80例(研究组)和行阴式子全宫切除术40例(对照组),观察并分析两组的临床指标及手术并发症。结果:研究组住院费用明显高于对照组(P0.05),手术时间、术中出血量及住院时间均低于对照组(P0.05);研究组无邻近脏器损伤,对照组输尿管损伤2例(5.00%),研究组患者出现手术损伤率明显低于对照组,差异存在统计学差异(x2=3.968,P=0.046);对两组患者术后随访1年,两组患者均无出现再手术情况;两组患者术后阴道残端均愈合较好,未出现阴道残端漏,患者无大小便困难及其他不适。结论:腹腔镜辅助下阴式子宫切除术治疗子宫良性病变疗效优于阴式子宫全切术,其手术时间、术中出血量及住院时间均较低,创伤小,更有利于患者恢复健康,在临床上值得应用推广。  相似文献   
5.
Evidence indicates that inflammatory response is significant during the physiological process of human parturition; however, the specific signaling pathway that triggers inflammation is undefined. Toll-like receptors (TLRs) are key upstream gatekeepers that control inflammatory activation before preterm delivery. Our previous study showed that TLR4 expression was significantly increased in human pregnancy tissue during preterm and term labor. Therefore, we explore whether TLR4 plays a role in term labor by initiating inflammatory responses, therefore promoting uterine activation. The results showed that expression of TLR4, interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), CC chemokine ligand 2 (CCL-2), and uterine contraction-associated proteins (CAPs) was upregulated in the human and mice term labor (TL) group compared with the not-in-labor (TNL) group, and the TLR4 level positively correlated with CAP expression. In pregnant TLR4-knockout (TLR4−/−) mice, gestation length was extended by 8 hr compared with the wild-type group, and the expression of IL-1β, IL-6, TNF-α, CCL-2, and CAPs was decreased in TLR4−/− mice. Furthermore, nuclear factor-κB (NF-κB) and P38MAPK activation is involved in the initiation of labor but was inhibited in TLR4−/− mice. In uterine smooth muscle cells, the expression of inflammatory cytokines and CAPs decreased when the NF-κB and P38MAPK pathway was inhibited. Our data suggest that TLR4 is a key factor in regulating the inflammatory response that drives uterine activation and delivery initiation via activating the NF-κB/P38MAPK pathway.  相似文献   
6.
目的:探讨不同分娩方式对产妇产后心理和生理的影响.方法:随机选择2011年1月~2011年12月在苏大附一院分娩的初产妇400例,其中剖宫产、阴道自然分娩各200例,对两组产妇产后42天心理状况、恶露持续时间、泌乳情况进行调查.结果:两种分娩方式对产妇产后42天发生焦虑和抑郁心理的影响无明显差别(P>0.05);阴道自然分娩组产后恶露持续时间短于剖宫产组,差异有显著意义(P<0.01).有抑郁、焦虑情绪的产妇泌乳始动时间显著长于正常产妇,24h泌乳量显著少于正常产妇(P<0.01).结论:剖宫产对产妇身体生理创伤大过阴道自然分娩,应严格控制剖宫产的适应症,鼓励阴道自然分娩.  相似文献   
7.
Duvatrienediol is a diterpene specifically occurred in tobacco plants and thought to be a precursor of tobacco aroma. Green tobacco leaves contained 0.2~1% of duvatrienediol per dry weight and it was corresponded to 30~60% of leaf surface lipid. Leaves on upper stalk position contained more of leaf surface lipid and duvatrienediol. In leaves on each stalk position, leaf surface lipid and duvatrienediol contents increased with leaf growth and decreased by over-maturation. Production of leaf surface lipid and duvatrienediol was affected by soil conditions or applied amount of nitrogen fertilizer. Both leaf surface lipid and duvatrienediol were decreased during curing of tobacco leaves, but the change in the latter was more drastic. Comparing to leaf surface lipid, changes in cytoplasmic lipid were less during growth and senescence of tobacco leaves.  相似文献   
8.
Continuous production of the E7 protein from different types of high risk human papilloma virus (HPV) is required for progression of malignancy. We developed antibodies against HPV type 16 E7 and E2 proteins to evaluate their utility as markers for diagnosis during early stages of cervical cancer. Forty biopsies from uterine cervices were diagnosed as low grade intraepithelial lesion (LSIL), high grade intraepithelial lesion (HSIL), squamous carcinoma (SC), in situ adenocarcinoma (ISA) and invasive adenocarcinoma (AC), all of which were infected with HPV 16. Immunohistochemistry was used to investigate the expressions of E7 and E2 (both from HPV 16) and p16. P16 was expressed in eight of 12 LSILs, in all HSILs, in 16 of 18 SC and in all ACs. E2 was expressed in six of 12 LSILs. E7 was positive in eight of 12 LSILs and in all HSIL and carcinomas. The expressions of E2 and E7 of HPV16 related to p16 expression confirmed the value of the viral oncogenic proteins as complementary to histology and support the carcinogenic model of the uterine cervix, because HPVDNA integration into cellular DNA implies the destruction of the gene encoding E2, which suppresses the expression of the E6 and E7 oncoproteins. E2 from HPV16 could be marker for LSILs, while E7 could be a marker for progression of LSILs to HSILs in patients infected by HPV16, because viral typing has little positive predictive value.  相似文献   
9.
胚泡着床窗口的分子调控   总被引:5,自引:0,他引:5  
着床窗口是指当胚胎发育到胚泡阶段时,子宫也增殖和分化到可接受状态,二者相互作用使胚泡着床的短暂时间.雌激素和孕酮是该过程的综合调控分子,它们通过多种局部信号分子的介导,使子宫中的各种细胞类型增殖、分化,为着床窗口的开放做出相互协调的反应.子宫与胚胎在着床窗口通过前列腺素、组织胺、降钙素、多种细胞因子和生长因子的旁分泌作用进行分子对话,使胚泡滋养层与子宫内膜上皮发生附着反应.着床窗口一旦开放,即自动向非接受态转化.  相似文献   
10.
胚胎着床是处于活化状态的胚泡与处于接受态的子宫相互作用,最后导致胚胎滋养层与子宫内膜建立紧密联系的过程。已证实白血病抑制因子(LIF)在哺乳动物胚胎着床过程中起着十分重要的调节作用。LIF通过其受体及信号传递亚单位gp130发挥其生物学功能。LIF对胚胎发育到胚泡阶段及以后内细胞团和滋养层细胞的生长和分化有明显的促进作用。 在小鼠中,LIF及其受体和gp130在着床期小鼠子宫内表达量最高,因此LIF可能在小鼠胚胎着床过程中起重要作用。在人中,LIF在子宫内膜中的表达与人胚胎着床的时间一致,提示LIF可能与人的胚胎着床紧密相关。此外,LIF在猪、羊、水貂、兔和臭鼬等动物胚泡着床前和着床期的子宫中也都有表达,并在着床期出现峰值。因此,LIF也可能在这些动物的胚胎发育和着床过程中有重要作用。LIF受体基因敲除小鼠表现为胎盘发育不全,这说明LIF对小鼠胎盘形成和胎盘的功能维持起重要作用。 小鼠子宫中LIF的表达可能受雌激素而上调。美洲长尾猴(绒)及兔子宫中LIF的表达则呈孕酮依赖性。然而孕酮可抑制人着床期子宫内膜腺上皮和蜕膜组织内LIF的表达。在不同种类的动物中,LIF在子宫中的表达有不同的调节机制。 胚泡在LIF基因敲除的雌鼠子宫内不能着床的原因并不是由于胚泡发育异常,而是由于雌鼠不能表  相似文献   
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