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1.
BackgroundPrior reports demonstrate the expression of estrogen and progesterone receptors in high-grade gliomas (HGGs), but the relationship between hormone receptor-positive disease and risk of HHGs in patients with breast cancer (BC) remains uncharacterized.MethodsUsing the SEER 18 registries (2000–2017), we examined the temporal trend of the incidence of HGGs and BC. The standardized incidence ratio was calculated to assess the risk of subsequent HGG in BC patients.ResultsDuring the study period, the incidence of BC and HGGs remained comparable for men and women. Among 976,134 patients with BC, we found a decreased incidence of HGGs in females, but not in males. Female BC patients with hormone receptor-positive disease were at a lower risk of developing glioblastoma and anaplastic astrocytoma.ConclusionOur study findings allude to the protective role of hormone exposure in the development of HGGs, which may lead to the development of therapies targeting hormonal pathways.  相似文献   
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Sex estimation by various forensic anthropology approaches is a crucial factor for identification of human skeletal remains. However, inexpensive, uncomplicated and reliable methods are still required, especially in a remote crime scene and a high crime incidence area. Here, we examined 13 sacral parameters from 78 independent skeletons derived from deceases found in Central Thailand (male, n = 46; female, n = 32) using simple standard anthropometric techniques for sex allocation. Discriminant analysis exhibited that anterior-posterior diameter of S1 vertebra corpus (APS) is the most accurate sacral parameter for sex determination in our study with 82.1% of correct discrimination rate. The accuracy could be improved up to 97.4% when additional three sacral variables including the length of sacrum measured from the medial anterior-superior sacral promontory to the medial anterior-inferior S5 vertebra (ASL), alar index (ALI), and the maximum anterior breadth of sacrum measured across sacral alar (ABS) were computed together with APS. These encourage the use of sacral morphometrics for sex assessment of human sacrum remains in Central Thailand. However, further investigation with broadening sacral morphometric data across the country might provide a promising sex determination equation from a sacral skeleton for Thai population.  相似文献   
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Adolescent males and females differ in their responses to social threat. Yet, threat processing is often probed in non-social contexts using the error-related negativity (ERN; Flanker EEG Task), which does not yield sex-specific outcomes. fMRI studies show inconsistent patterns of sex-specific neural engagement during threat processing. Thus, the relation between threat processing in non-social and social contexts across sexes and the effects perceived level of threat on brain function are unclear. We tested the interactive effect of non-social threat-vigilance (ERN), sex (N = 69; Male=34; 11–14-year-olds), and perceived social threat on brain function while anticipating feedback from ‘unpredictable’, ‘nice’, or ‘mean’ purported peers (fMRI; Virtual School Paradigm). Whole-brain analyses revealed differential engagement of precentral and inferior frontal gyri, putamen, anterior cingulate cortex, and insula. Among males with more threat-vigilant ERNs, greater social threat was associated with increased activation when anticipating unpredictable feedback. Region of interest analyses revealed this same relation in females in the amygdala and anterior hippocampus when anticipating mean feedback. Thus, non-social threat vigilance relates to neural engagement depending on perceived social threat, but peer-based social contexts and brain regions engaged, differ across sexes. This may partially explain divergent psychosocial outcomes in adolescence.  相似文献   
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Background. It has been reported that gender differences in cardiovascular outcomes found in adults also are present in children who undergo surgical repair for congenital heart disease. Methods. California statewide hospital discharge data 1989–99 were used to study outcomes in children <18 years undergoing cardiac surgery. Hospital discharge data were linked to death registry data to study postdischarge death within 30 days of discharge. We used logistic regression to evaluate the effect of gender on mortality controlling for age, race and ethnicity, type of insurance, household income, date and month of surgery, type of admission, hospital case volume, and various types of procedures. Results. There were 25 402 cardiac surgery cases with 1505 in‐hospital deaths (mortality rate of 5.92%). An additional 37 deaths occurred within 30 days after hospital discharge. Crude mortality rates for males (5.99%) and females (5.84%) were not significantly different. However, fewer neonates were female and females underwent a higher proportion of low‐risk procedures than males. Logistic regression revealed that females, compared with males, had a significantly higher odds ratio (OR) for in‐hospital mortality (OR = 1.18, P < .01) and overall (up to 30 days post discharge) mortality (OR = 1.18, P < .01). The risk‐adjusted length of hospital stay was similar between females and males while charges per hospital day were slightly higher in females than males. The prevalence of Down syndrome, pulmonary hypertension, and failure to thrive were higher in females. Conclusions. Female gender is associated with an 18% higher in‐hospital and 30‐day postdischarge mortality as compared with male gender. There was no difference in length of hospital stay between males and females. The mechanism by which female gender acts as a risk factor requires further investigation.  相似文献   
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关于抑制素的回顾与展望   总被引:1,自引:0,他引:1  
吴惠梅  李慕军 《医学综述》2006,12(10):579-581
1923年,随着生殖腺反馈调节垂体功能的概念的提出,关于抑制素的研究开始了。抑制素是一种非类固醇类物质,能够抑制垂体细胞的活性。1932年,这种物质在水状的睾丸提取物中得到证实,并被命名为抑制素。又经过了50多年的研究,到1985年,抑制素才被纯化和克隆。而直到化验技术的进步使人和动物的循环浓度得以分析,抑制素的生理活性的揭示才得以完成。本文综述抑制素的历史、生理作用及其在辅助生殖技术中的最新的应用和研究。  相似文献   
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Our previous work demonstrated that the hormone response to stress and the negative feedback inhibition to these hormones are sex-dependently altered by prenatal morphine exposure in adult rats. An alteration in the glucocorticoid negative feedback inhibition is mediated by glucocorticoid receptors (GR) that are distributed throughout the brain, and mineralocorticoid receptors (MR) localized mainly in the hippocampus and involved in a tonic influence of brain functions. Therefore, the present study examined the binding characteristics of MR and GR in young adult male and female rats exposed prenatally (E11-E18) to morphine (10 mg/kg/2 x /day), saline or no treatment at all (controls). At 60-90 days of age, animals were adrenalectomized (ADX) 24 h prior to decapitation. The hippocampus and hypothalamus were dissected for saturation binding assays. The data demonstrate that prenatal stress due to maternal saline injections up-regulates MR and GR binding in the hippocampus of adult male rats and this effect is prevented by prenatal morphine exposure. There is no effect of prenatal morphine exposure on GR binding in the hypothalamus of males. In female rats, prenatal morphine exposure does not affect the binding of MR and GR in the hippocampus or GR in the hypothalamus relative to controls; however, they are affected by ovarian hormone fluctuation. Moreover, prenatal stress decreases MR binding in the hippocampus of diestrous females and GR binding in the hypothalamus of estrous females. Both decreases are prevented by prenatal morphine exposure. Thus, the present study demonstrates that: (1) prenatal stress due to maternal saline injections alters MR and GR binding of adult male and female rats and is prevented by prenatal morphine exposure; (2) the MR and GR binding in adult female rats are affected by ovarian hormone fluctuations.  相似文献   
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The results of cardiovascular autonomic reflex tests on 224 healthy, randomly selected subjects were analysed to study possible sex differences in the autonomic responses. The heart rate response to the Valsalva manoeuvre (Valsalva ratio) was greater in females over 50 years than in males of the same age (1.58 ± 0.34 vs. 1.44 ± 0.30,p < 0.05). The heart rate response to deep breathing (E/I ratio) was higher in females under 50 years than in males under 50 years (1.37 ± 0.17 vs. 1.34 ± 0.18,p < 0.001). The diastolic blood pressure response to isometric handgrip was higher in males under 50 years than in females of the same age (p < 0.05). Although there were sex differences in the magnitude of the responses, the effect of age was similar in males and females and accelerated attenuation of the autonomic responses could not be demonstrated with increasing age. It can be concluded that significant sex differences exist in cardiovascular autonomic responses. The implication of such differences need consideration.  相似文献   
10.
The incidence of lower urinary tract dysfunction increases during the climacteric, and there is embryological, biochemical and epidemiologic evidence to suggest that depleted estrogen status is at least partially responsible. Twelve climacteric women underwent full assessment before and 1 year after treatment with a 50 mg subcutaneous estradiol implant +5 mg norethisterone for 7 days per month. Assessment consisted of a symptoms questionnaire, midstream urine sample, uroflowmetry, videocystourethrography with pressure flow studies, and urethral pressure profilometry. Subjectively, only the symptom of nocturia significantly improved. There was no change in flow variables but there was a significant decrease in residual urine and the degree of bladder base descent. Cystometric capacity was slightly but significantly decreased, and two patients developed genuine stress incontinence whilst on treatment. Nonetheless, there was a significant improvement in urethral pressures at rest but not under stress. This effect was predominantly in the proximal urethra. These data do not support the contention that estrogen replacement therapy is beneficial for lower urinary tract dysfunction during the climacteric.  相似文献   
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