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31.
克罗米酚对血清雌激素和孕激素水平的影响   总被引:1,自引:0,他引:1  
目的探讨克罗米酚(CC)在诱发排卵过程中对雌、孕激素水平的影响。方法采用放射免疫法,测定16例不明原因不孕妇女在自然周期和用药周期的排卵前1天和排卵后10天血清雌二醇(E2)和孕酮(P)浓度。结果排卵前1天和排卵后10天,用药周期的E2、P浓度均高于自然周期(P<0.05)。结论克罗米酚在诱发排卵过程中可导致内源激素平衡紊乱。  相似文献   
32.
随着妇女平均寿命的延长,绝经后的问题日益受到全社会的广泛关注,旨在改善妇女生活质量的激素替代治疗(HRT)所引发的问题也不断涌现。2002年7月,美国国立卫生研究院心脏、肺和血液研究所宣布。妇女健康初始行动(WHI)在健康绝经后妇女中使用雌激素加孕激素的临床试验由于乳腺癌发病相对风险增加26%,且并无总体益处予以提前终止。在上述对HRT弊端新认识的背景下,中医中药面临着前所未有的走向世界的新契机。大量临床和实验研究证明,中医中药对更年期综合征引起的各种症状有较好的治疗效果,而且副作用少,因此中医辨证治疗有望替代或补充雌激素疗法对更年期综合征的治疗作用,最大限度地减少完全用雌激素替代治疗所引起的副作用。  相似文献   
33.
BACKGROUND: At present, there is still lack of effective drugs for chronic spinal cord injury, whereas it is found recently that estrogen has a neuroprotective effect on brain and spinal cord injuries. OBJECTIVE: To observe the effect of estrogen on the apoptosis of nerve cells after gradual chronic spinal cord injury in ovariectomized rats. DESIGN: A randomized controlled animal trial. SETTING: Institute of Orthopaedics, the Second Hospital of Lanzhou University. MATERIALS: Sixty-five female Wistar rats of common degree, weighing 220–250 g, were provided by the experimental animal center of Lanzhou University. The rats were randomly divided into sham-operated group (n =5), estrogen-treated group (n =30) and saline control group (n =30), and the latter two groups were observed at 1, 3, 7, 14, 28 and 60 days respectively, and 5 rats for each time point. METHODS: All the rats were treated with bilateral oophorectomy 2 weeks before the experiment. T10 vertebral lamina was revolved into using plastic screw. The spinal canal impingement was not induced initially. After that, the original incision was opened to expose the screw every 7–10 days. MAIN OUTCOME MEASURES: The apoptosis and Caspase-3 positive cells in the damaged spinal cord were detected using terminal deoxynucleotidal transferase-mediated dUTP-biotin nick end labeling (TUNEL) method and Caspase-3 immunohistochemical staining at 1, 3, 7, 14, 28 and 60 days after chronic spinal cord injury respectively. RESULTS: Totally 65 rats were used, and the deleted ones during the experiment were supplemented by others. Changes of Caspase-3 expression after spinal cord injury: In the sham-operated group, only a small amount of Caspase-3 proteins were observed in the rat spinal cord, mainly located in motor neurons of spinal cord anterior horn. In the estrogen-treated group and saline control group, positive cells expressed occasionally at 1 day postoperatively, began to increase obviously at 7 days after injury, strongly expressed at 14 and 28 days, but decreased at 60 days, mainly located in the neurons of spinal cord gray matter anterior horn, and they expressed fewer in the motor neurons and white matter of ventral horn, and there were obvious differences between the estrogen-treated group and saline control group at 7, 14, 28 and 60 days (P < 0.05). CONCLUSION: Estrogen can reduce the apoptosis of nerve cells and promote the recovery of neurological function following gradual chronic spinal cord injury.  相似文献   
34.
目的:观察不同浓度的尼尔雌醇(NYL)和左炔诺孕酮(LNG)对人成骨肉瘤MG-63细胞株ERα和ERβ表达的作用,探讨旁分泌效应对ERα和ERβ基因表达的影响。方法:人成骨肉瘤MG-63细胞株分为(1)空白对照组:用含1% BSA无血清MEM培养液培养48 h;(2)阳性对照组:培养液中加入10-8 mol/L的17β-estradiol (E2) 培养48 h;(3)药物处理组:培养液中分别加入10-10,10-8,10-6 mol/L的NYL或LNG培养48 h;(4)药物处理+换液组:培养液中分别加入10-10 mol/L的NYL或10-8 mol/L LNG培养48 h,每12 h更换新的含有相应药物的培养液。用半定量RT-PCR检测各组细胞ERα和ERβmRNA的表达。结果:NYL及LNG均能诱导ERα和ERβ亚型mRNA表达上调,诱导ERαmRNA表达的最强作用浓度均为10-6 mol/L。NYL,LNG对ERβ mRNA表达最强作用浓度分别为10-10,10-8 mol/L。每12 h更换干预培养液对ERα表达无影响,但可抑制ERβ的表达。结论:NYL和LNG均可诱导MG-63细胞株ERα和ERβ mRNA表达上调,且2种亚型的表达存在相互制约关系;在NYL和LNG诱导ER亚型表达上调过程中ERβ的表达可能受到旁分泌作用的影响。  相似文献   
35.
Low amplitude pulses of estradiol-17β (E2-17β) are more effective than large single bolus injections or constant exposure to E2-17β in inducing progesterone-facilitated sex behavior in female rats and guinea pigs. The present study examined whether the increased responsiveness to E2-17β is due to an increase in the number of estrogen receptors in the estrogen receptor rich areas of the hypothalamus and amygdala. Initial studies examined the rapid effects (20 min) of a high dose of E2-17β (50 μg) on estrogen receptor immunostaining using either the H222 antibody or the ER 21 antiserum. ER 21 immunostaining was not affected by the E2-17β treatment suggesting that it binds to both occupied and unoccupied estrogen receptors. Therefore the ER 21 antiserum was used to characterize the regulation of estrogen receptor immunoreactivity (ER-IR) by E2-17β. ER-IR was examined for 48 h and serum E2-17β for 24 h following a 2 μg s.c. injection of E2-17β (a dose similar to that used in multiple pulse paradigms). Serum E2-17β peaked 15 to 30 min following the injection and returned to baseline values by 1 h. In all but one area maximal suppression of ER-IR occurred at 12 h. In summary, 1) decreases in estrogen receptor immunoreactivity following E2-17β are consistent with studies in which estrogen receptors were assayed by binding assays and estrogen receptor mRNA was determined by in situ hybridization; 2) the ER 21 antiserum is able to detect both occupied and unoccupied estrogen receptors and 3) H222 immunoreactivity is influenced by the presence of E2-17β, so that the level of H222-IR is a reflection of ligand/receptor binding dynamics. The data suggest that up-regulation of estrogen receptors does not account for the increase in behavioral sensitivity which is observed following multiple pulses of E2-17β.  相似文献   
36.
Inanimate structures cannot detect and repair their fatigue damage or microdamage, so to minimize it they need more structural material and strength. Living bone handles this matter differently. Bone modeling drifts adapt bone architecture and strength to the loads on bones in ways that tend to keep strains from exceeding a “modeling threshold” range. Strains (or equivalent features) above that threshold switch mechanically controlled modeling ON. Where strains stay below that threshold, this modeling goes OFF. Repeatedly loading-deloading a bone causes microdamage in it, and basic multicellular unit (BMU)-based bone remodeling normally repairs it. Where strains stay below an operational “microdamage threshold,” remodeling can repair whatever microdamage happens for as long as it happens. Strains above that threshold can cause too much microdamage to repair completely and lead to fatigue fractures of trabeculae or whole bones. The modeling threshold normally lies comforably below the microdamage threshold. Since modeling normally adjusts bone architecture to keep strains from exceeding the modeling threshold, this keeps strains below the microdamage threshold, too, and voluntary activities do not cause more microdamage than remodeling can repair. Therefore, long-distance runners do not need more bone mass and strength than nonrunners of comparable age, sex, and body size.  相似文献   
37.
雌激素上调LRP16基因表达的研究   总被引:13,自引:4,他引:9  
目的:鉴定LRP16基因的表达调控途径并探讨其可能机制。方法:对LRP16基因进行启动子序列顺式作用元件和信息学角度的SAGE(serial analysis of gene expression)谱分析,提示雌激素对其可能具有转录调控作用。为证实这一作用,构建了LRP16基因启动子序列(2.6kb)调控的荧光素酶报告子(pS0),并与雌激素受体α和β(ERα,ERβ)真核表达载体共转染COS-7和MCF-7细胞,加入雌二醇(β-E2)培养,lueiferase assay方法测定相对荧光素酶活性。结果:报告子pS0与ERα真核表达载体共转染细胞的相对荧光素酶活性较非共转染组及pS0/ERβ表达载体共转染组显著升高,并且在两种细胞中的升高幅度接近。结论:LRP16是受雌激素调控的一个新识别的靶基因,具体调控途径由雌激素变构激活的ERα直接介导,其临床意义有待进一步研究。  相似文献   
38.
用酶联亲合组化法对46例肺肿瘤细胞进行了雌激素受体(ER)和孕激素受体(PR)检测。同时测定14例肺瘤肿患者血清雌二醇(E_2)浓度。结果表明:肺肿瘤 ER 阳性率为36.9%,PR 阳性率为13.0%。阳性率与性别、病理类型及血浆 E_2浓度无关。认为肺癌的发生发展可能与雌激素有依赖关系,提示内分泌疗法可能会成为原发肺肿瘤的一种治疗手段。另用 ABC 法对上述46例肺肿瘤中的29例进行了花生凝集素受体(PNA-R)和麦胚凝集素受体(WGA-R)的检测,PNA-R 在腺癌大都为顶浆型分布,鳞癌和透明细胞癌则多为胞膜型分布。结果提示 PNA-R 是肺癌分化过程中的一种标志,对肺癌分型、预后判断有一定协助作用。同时将29例肺肿瘤 PNA-R 与 ER 状况作对比研究,探讨了二者之间的相关性及可能的发生机制。  相似文献   
39.
Epidermal growth factor receptor (EGFR), determined by the Scatchard curve method, was found in 22 cases of a random series of 100 patients with breast carcinoma. Two groups of patients were identified, one (n = 16) with a low concentration (0–50 fm/mg protein) of EGFR but with a high affinity (Kd = 3.2 nM), and the other (n = 6) with a high concentration (90–210 fm/mg protein) of EGFR but with a lower affinity (Kd = 6.3 nM).A significant inverse relationship was found between the presence of EGFR and receptors for estrogen (p<0.001) and progesterone (p = 0.001). EGFR was found in no (0/8) tumors with Grade I histoprognostic grade, 17% (10/58) Grade II, and 38% (11/29) Grade III (p<0.05). EGFR is present therefore in poorly differentiated tumors and associated with other factors of poor prognosis. Ourin vivo analyses confirm results found in tissue culture derived from human breast carcinoma cells.With the technical assistance of J. Barraque.  相似文献   
40.
目的 研究雌激素联合保妇康栓治疗绝经后宫颈人乳头瘤病毒(HPV)感染的临床疗效。方法 选取2019年2月—2022年7月无锡市第九人民医院收治的89例绝经后宫颈HPV感染患者,按治疗方法不同分为研究组(46例)和对照组(43例)。对照组接受雌激素治疗,研究组在对照组基础上接受保妇康栓治疗。两组均持续治疗3个月。对比两组异常分泌物持续时间、HPV转阴时间、临床疗效、炎症因子、免疫功能、液基薄层细胞学检查(LCT)评分与宫颈炎症评分及不良反应。结果 研究组异常分泌物持续时间、HPV转阴时间均短于对照组(P <0.05)。研究组总有效率高于对照组(P <0.05)。研究组治疗前后白细胞介素-4、γ干扰素、白细胞介素-2、肿瘤坏死因子-α的差值均高于对照组(P <0.05)。研究组治疗前后CD3+、CD19+、CD3+CD8+、CD3-CD56+的差值均高于对照组(P <0.05)。研究组治疗前后LCT评分、宫颈炎症评分的差值均高于对照组(P <0.05)...  相似文献   
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