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OBJECTIVE: The aim of the present study is to figure out the immunohistochemical expression of transforming growth factor-alpha (TGF-alpha), epidermal growth factor (EGF), and vascular endothelial growth factor (VEGF) in hyperstimulated rat ovaries. METHODS: Twenty Wistar-Albino adult female rats (250-300 g) were taken into the study. The animals were randomly divided into two groups, each containing 10 rats: (i) stimulation group and (ii) control group. In the stimulation group, a stimulation regimen was administered to induce follicular maturity and ovarian hyperstimulation syndrome (OHSS) at the end using a 30-IU follicle-stimulating hormone that was administered subcutaneously for 4 consecutive days, followed by a 30-IU human chorionic gonadotropin on day 5 to induce ovulation. The rats, in the control group, received 0.2 ml of 0.9% NaCl for 5 consecutive days to mimic the conditions of the study animals. At the end of the treatment period, all rats underwent ovariectomy and the sections of ovaries were stained for the TGF-alpha, EGF, and VEGF. RESULTS: The expression of TGF-alpha, EGF, and VEGF in the endothelium, the stroma, the granulosa cells, and the corpus luteum was found to be significantly higher in the stimulated group, compared to that in the control group ( p < 0.05). CONCLUSION: TGF-alpha, EGF, and VEGF are found to have increased in the hyperstimulated ovaries and this finding seems to be involved in the OHSS pathogenesis.  相似文献   
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OBJECTIVE: To investigate the respective roles of the mode of delivery and strength of pelvic floor muscles in the sexual function of women. METHOD: Thirty-two women who were delivered vaginally and 21 women who underwent cesarean delivery at the Celal Bayar University School of Medicine Obstetrics Department were enrolled in the study, and 15 nulliparas were recruited as controls. Sexual function was assessed in all women by a validated questionnaire (the Female Sexual Function Index). Desire, arousal, lubrication, orgasm, satisfaction, and pain were measured separately, and pelvic floor muscle strength was assessed by a perineometer. Sexual function was compared among the 3 groups. The correlation between pelvic floor muscle strength and sexual function was also investigated. RESULTS: Pelvic floor muscle strength was significantly lower in the group vaginally delivered compared with the group delivered by cesarean section and the nulliparous group (P<0.05). There was no difference between the groups regarding sexual function (P>0.05), and there was also no correlation between sexual function and pelvic muscle strength. CONCLUSION: Pelvic floor muscle strength and mode of delivery did not affect sexual function in our study participants. The muscular component of female sexual function should be further investigated.  相似文献   
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MGMT promoter hypermethylation of aggressive pituitary adenomas and pituitary carcinomas and low protein expression are implicated in improved response to treatment with temozolomide (TMZ). The aim of the present study was to investigate MGMT promoter methylation and immunoexpression in an aggressive subset of pituitary adenomas and carcinomas. Our material consisted of 12 silent subtype 3 (SS3) adenomas, 10 primary carcinomas, and 4 disseminated metastases. Two different tissue samples of 7 of the 12 SS3 adenomas and all carcinomas were analyzed for MGMT promoter methylation and immunohistochemical expression of MGMT. Immunoexpression was assessed semi-quantitatively as a percentage of immunoreactive nuclei. Overall 33% of carcinomas exhibited homogenous MGMT methylation in tumor and metastatic specimens. Low immunohistochemical MGMT expression was noted in 50% of carcinomas. Overall, 42% of the SS3 adenomas exhibited MGMT promoter methylation. MGMT immunostaining was predominantly negative (92%), with homogenous immunostaining results across different samples. Whereas all the methylated SS3 adenomas had low MGMT immunoreactivity, five unmethylated adenomas exhibited absent/low MGMT expression. There was no relationship between methylation status and MGMT immunoexpression was not apparent. MGMT methylation and low immunohistochemical expression seen in a subset of carcinomas and SS3 adenomas, suggesting that a subset of tumors may respond to treatment with TMZ. Heterogeneous MGMT methylation status in SS3 adenomas and the lack of concordance between methylation and immunohistochemical expression of MGMT suggest complex regulatory mechanisms, highlighting the need for improved methods in the research on a correlation between MGMT changes and response to TMZ.  相似文献   
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Stress is a multidimensional construct. To accurately represent stress physiology, multiple stress measures across multiple stress-related systems should be assessed. However, associations may be masked given that different systems underlie different time courses. Salivary cortisol and alpha-amylase (sAA) are reliable biological stress markers of the sympathetic nervous system (SNS) and the hypothalamus pituitary adrenal (HPA) axis, respectively. Studies examining the link between sAA and cortisol levels in response to stress have produced inconsistent results. Here, we investigated whether the covariance of stress-induced sAA and cortisol release is dependent on the distinct temporal dynamics of the two stress markers. A total of 50 male participants were exposed to a psychological laboratory stressor with high frequency (2-min interval) saliva sampling in two independent studies. Synchronized time series of sAA and cortisol measures before, during and after stress induction were obtained. Cross-correlation analysis was applied to test for the association of sAA and cortisol levels at various stages relative to the onset of the stressor. Positive and negative cross-correlations between lagged pairs of sAA and cortisol measures were found in both studies. The strongest correlation was found for sAA preceding cortisol release by 13.5 min (r = .27, p < .001). With a smaller effect size cortisol also significantly preceded sAA by 13.5 min (r = -.16, p < .001). We suggest that sAA and cortisol stress responses are reliably associated at various time lags throughout a stressful situation. As a possible connection site between HPA axis and SNS that may underlie sAA-cortisol associations, we discuss CRF neurons of the hypothalamus involved in sympathetic regulation.  相似文献   
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