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1.
子宫肌瘤患者及接受UAE治疗后血清性激素水平分析   总被引:2,自引:0,他引:2  
目的:探讨性激素在子宫肌瘤发病中的意义。方法:采用化学发光技术检测正常对照61例(对照组)、子宫肌瘤患6l例(患组)以及44例子宫肌瘤接受子宫动脉栓塞治疗(UAE)后的患,血清促卯泡成熟激素(FSH)、促黄体生成激素(LH)、雌激素(E2)、垂体泌乳素(PRL)、睾酮(T)水平。结果:子宫肌瘤患组的血清FSH、LH、PRL、T水平均明显高于对照组;血清E2水平与对照组无显差异。其中44例接受UAE治疗的子宫肌瘤患术后血清LH、E2、PRL、T水平均比术前明显降低,FSH与术前无显差异;术后血清FSH、PRL、T水平均明显高于对照组,LH、E2水平明显低于对照组。结论:PRL、T是子宫肌瘤的发病因素。  相似文献   
2.
目的 测定颅内动脉瘤破裂出血患者血清泌乳素 (PRL)、生长激素 (GH)的含量变化 ,探讨其与病情演变的关系。方法 对 3 5例颅内动脉瘤破裂出血患者发病后 1~ 3d ,发病后 7~ 9d ,发病后 13~ 15d血清PRL、GH进行动态观察 ,用TCD检测大脑中动脉血流速度 (VMCA)。结果 颅内动脉瘤破裂出血患者血清PRL、GH发病后 1~ 3d、发病后 7~ 9d各均值明显高于对照组 (P <0 .0 5 ) ,尤以发病后 7~ 9d变化最明显 ;术前、术后有脑血管痉挛组和非脑血管痉挛组也有明显差异 (P <0 .0 5 )。结论 血清GH、PRL含量与蛛网膜下腔出血 (SAH)的病情演变、脑血管痉挛 (CVS)有关  相似文献   
3.
抗肌萎缩蛋白基因是迄今发现的人类最大基因,长约2300 kb,含有75个外显子。对该巨大基因的研究是近年来医学分子生物学研究的一个热点。虽然抗肌萎缩蛋白基因HindⅢ片段排序后就知道第51号外显子位于3.lkb的第40号HlndⅢ片段中,由于抗肌萎缩蛋白基因组DNA至今未被克隆,233bP的第51号外显子在3.lkp HindⅢ片段中的部位并不知道,也不知道它两侧的DNA结构。51号外显子  相似文献   
4.
早吸吮勤吸吮对早泌乳的影响   总被引:2,自引:0,他引:2  
为了探讨产后半小时内早吸吮、勤吸吮对早泌乳的影响。选择116例足月妊娠孕产妇,分别在第二产程及产后半小时抽取母亲静脉血,采用放射免疫双抗法(DARIA)测定胎儿娩出前、吸吮后和未吸吮时,母亲血清垂体催乳素(PRL)值。结果表明:第二产程时两组血清PRL值无显著差异。而产后半小时早吸吮的母亲体内血清中PRL水平明显高于未吸吮的血清PRL值。早吸吮的母亲泌乳早。  相似文献   
5.
探讨孕早期血清妊娠相关蛋白-A(PAPP-A) 和整合素-金属蛋白酶12分泌期蛋白(ADAM12-s)、催乳素(PRL)和孕酮(P)水平变化及其与胚停育的相关性。应用时间分辨荧光免疫分析法测定患者血清中 PAPP-A、ADAM12-s、PRL和孕酮P表达水平,并对测定结果及孕妇妊娠结局进行统计分析。与正常妊娠组孕妇PAPP-A、ADAM12-s、PRL和孕酮P水平相比,胚胎停育组患者PAPP-A、ADAM12-s、PRL和孕酮P平均中位数水平显著降低,差异具有统计学意义(P<0.05)。正常妊娠组和胚胎停育组孕妇血清内PAPP-A、ADAM12-s、PRL和孕酮P水平与患者的孕周数存在显著的直线相关关系,Person相关系数为正值,(P<0.05)。孕早期孕妇血清 PAPP-A、ADAM12-s、PRL和孕酮(P)含量随孕周数增加而显著上升,可以作为预测胚胎停育的有效临床指标。  相似文献   
6.
We have studied the relationship between the prolaction (PRL) release induced by thyroliberin (TRH) and theophylline and the formation and inactivation of adenosine 3', 5'-cyclic monophosphate (cyclic AMP) in cultured rat-pituitary cells (GH3 cells). TRH, which stimulated prolactin release, increased cyclic AMP formation and stimulated transiently both the low- and high-Km cyclic phosphodiesterases. The maximal effect on the phosphodiesterase was observed at 30 mM TRH. The stimulatory effect of TRH on the activity of the cyclic AMP phosphodiesterases was duplicated by incubation of the cells with cyclic AMP (2-10 mM). In washed particulate GH3 cell fractions, TRH increased the adenylyl cyclase activity up to 180%. Treatment of GH3 cells with theophylline stimulated the release of PRL and inhibited cyclic AMP degradation probably leading to the measured increase in cellular concentrations of the nucleotide. The effects of TRH and theophylline on cellular cyclic AMP concentrations and on PRL release were additive. There was a positive correlation between PRL release and cellular cyclic AMP concentration (r = 0.97). The elevations observed in cellular cyclic AMP concentration after TRH treatment are due to increased formation which in turn leads to phosphodiesterase activation. Therefore, cyclic AMP formation appears to be an intermediary step in the stimulus-secretion coupling caused by the tripeptide.  相似文献   
7.
In the turkey, exogenous serotonin (5-hydroxytryptamine, 5-HT) increases prolactin (PRL) secretion by acting through the dopaminergic (DAergic) system. In the present study, infusion of the 5-HT2C receptor agonist, (R)(−)-DOI hydrochloride (DOI), into the third ventricle stimulates PRL secretion, whereas the 5-HT1A receptor agonist, (+/−)-8-OH-DPAT hydrobromide (DPAT), inhibits PRL secretion. Using the immediate-early gene, c-fos, as an indicator of neuronal activity, in situ hybridization histochemistry showed preferential c-fos co-localization within tyrosine hydroxylase immunoreactive neurons (the rate limiting enzyme in DA synthesis) in the areas of the nucleus preopticus medialis (POM) and the nucleus premammillaris (PMM), in response to DPAT and DOI, respectively. To clarify the involvement of 5-HT1A and 5-HT2C receptors in PRL regulation, their mRNA expression was determined on hypothalamic tissue sections from birds in different reproductive stages. A significant difference in 5-HT1A receptor was observed, with the POM of hypoprolactinemic short day and photorefractory birds showing the highest expression. 5-HT2C receptors mRNA did not change during the reproductive cycle. The data presented support the notion that DA neurons in the PMM and POM mediate the stimulatory and inhibitory effects of 5-HT, respectively, on PRL secretion and the 5-HTergic system can both stimulate and inhibit PRL secretion.  相似文献   
8.
Somatostatin is a peptide with a potent and broad antisecretory action, which makes it an invaluable drug target for the pharmacological management of pituitary adenomas and neuroendocrine tumors. Somatostatin receptors (SSTR1, 2A and B, 3, 4 and 5) belong to the G protein coupled receptor family and have a wide expression pattern in both normal tissues and solid tumors. Investigating the function of each SSTR in several tumor types has provided a wealth of information about the common but also distinct signaling cascades that suppress tumor cell proliferation, survival and angiogenesis. This provided the rationale for developing multireceptor-targeted somatostatin analogs and combination therapies with signaling-targeted agents such as inhibitors of the mammalian (or mechanistic) target of rapamycin (mTOR). The ability of SSTR to internalize and the development of rabiolabeled somatostatin analogs have improved the diagnosis and treatment of neuroendocrine tumors.  相似文献   
9.
The contents of a purified somatotroph and mammotroph secretory granule fraction isolated from rat anterior pituitaries were solubilized in 4 M urea and analyzed by PAGE. In gels electrophoresed under a variety of conditions and stained with Coomassie Blue only two major bands, identified as GH and PRL, were present. In gels stained with Stains-All (which stains anionic substances), several additional bands were detected. When quarter pituitaries were labeled with a [3H]amino acid mixture, GH and PRL accounted for greater than 95% of the radioactivity incorporated into the granules. After labeling with [35S]sulfate, two classes of radiolabeled sulfated components were detected in the granules: a class of trypsin-sensitive macromolecular components which were coincident with two of the bands seen after Stains-All, and a class of low molecular weight components. In order to examine the distribution of the two classes of sulfated components within somatotroph and mammotroph granules, granules were suspended in 0.4% (w/v) Lubrol PX at pH 4.0, a treatment which has been shown to selectively solubilize somatotroph granule contents leaving mammotroph granule cores intact. This treatment was found to solubilize greater than 95% of the GH and greater than 99% of the radiolabeled, low molecular weight sulfated components; in contrast, there was virtually no solubilization of either PRL or macromolecular sulfated components. The findings indicate (a) that [35S]sulfate is incorporated into both somatotroph and mammotroph granules, and (b) that the low molecular weight sulfated components are associated with somatotroph granules whereas the macromolecular sulfated components are associated with mammotroph granules.  相似文献   
10.
Prolactin (PRL) is a polypeptide hormone with a wide range of physiological functions, and is critical for female reproduction. PRL exerts its action by binding to membrane bound receptor isoforms broadly classified as the long form and the short form receptors. Both receptor isoforms are highly expressed in the ovary as well as in the uterus. Although signaling through the long form is believed to be more predominant, it remains unclear whether activation of this isoform alone is sufficient to support reproductive functions or whether both types of receptor are required. The generation of transgenic mice selectively expressing either the short or the long form of PRL receptor has provided insight into the differential signaling mechanisms and physiological functions of these receptors. This review describes the essential finding that both long and short receptor isoforms are crucial for ovarian functions and female fertility, and highlights novel mechanisms of action for these receptors.  相似文献   
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