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We present array comparative genomic hybridization (aCGH) characterization of an unbalanced X-autosome translocation with an Xq interstitial segmental duplication in a 16-year-old girl with primary ovarian failure, mental retardation, attention deficit disorder, learning difficulty and facial dysmorphism. aCGH analysis revealed an Xq27.2–q28 deletion, an 11q24.3–q25 duplication, and an inverted duplication of Xq22.3–q27.1. The karyotype was 46,X,der(X)t(X;11)(q27.2;q24.3) dup(X)(q27.1q22.3). We discuss the genotype–phenotype correlation in this case. Our case provides evidence for an association of primary amenorrhea and mental retardation with concomitant unbalanced X-autosome translocation and X chromosome rearrangement.  相似文献   
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The objective of this work was to evaluate the associations between levels of endogenous sex hormones in women at midlife and lipoprotein subclasses. One hundred and twenty women (68 late peri-/postmenopausal and 52 pre-/early perimenopausal) from the Study of Women’s Health Across the Nation (Pittsburgh site) were included. Lipoprotein subclasses were quantified using NMR spectroscopy. Participants (57.5% White and 42.5% Black) were 50.4 ± 1.9 years old. Adjusting for age, race, cycle day of blood draw, BMI, physical activity, and alcohol consumption, a negative correlation was found between estradiol (E2) and medium-small LDL particle (LDL-P) concentration (ρ = −0.19, P = 0.04). Further, E2 was positively correlated with HDL particle (HDL-P) size (ρ = 0.22, P = 0.02). For sex hormone binding globulin (SHBG), independent negative correlation was found with total small LDL-P concentration. SHBG was also positively correlated with LDL-P and HDL-P sizes (P < 0.05 for all). For free androgen index (FAI), positive correlations were found with concentrations of total VLDL particles, total LDL-Ps, and total small LDL-Ps. Additionally, FAI was negatively correlated with large HDL-P concentration, and HDL-P and LDL-P sizes (P < 0.05 for all). Lower levels of E2 and SHBG, and higher levels of FAI were associated with a more atherogenic profile of lipoprotein subclasses. Sex hormone levels at midlife may increase women’s risk of coronary heart disease.  相似文献   
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雌二醇对豚鼠心室肌细胞L型钙通道的抑制作用   总被引:3,自引:1,他引:2  
目的和方法:采用全细胞膜片钳技术,研究不同浓度(1μmol/L、10μmol/L、100μmol/L)雌二醇(estradiol,EST)对豚鼠心室肌细胞L型钙电流(ICa.L)的影响。结果:①EST明显抑制ICa.L,1μmol/L、10μmol/L、100μmol/LEST分别使峰值ICa.L降低30.5%,50.0%(P〈0.01)和68%(P〈0.01),该作用具有浓度依赖性;②EST对I  相似文献   
67.
Estrogenic regulation of cholecystokinin (CCK) and its receptors is correlated with the initiation and termination of lordosis behavior. To understand the effect of circulating estrogen concentration on the temporal aspects of CCK mRNA expression in the posterodorsal medial amygdaloid nucleus (MeApd) and the central part of the medial preoptic nucleus (MPNc) of the limbic-hypothalamic circuit, ovariectomized female rats were treated with a 10 mm Silastic™ capsule filled with estradiol, a bolus injection of 50 μg estradiol benzoate or 2 μg estradiol benzoate every 4 days for five “cycles.” In situ hybridization was used to compare the relative changes of CCK mRNA levels at 0 h to levels measured at 6, 12, 24, 48, 72, or 96 h after estrogen administration. In the MPNc and the MeApd, the 10-mm capsule significantly increased and maintained CCK mRNA levels from 6 to 96 h. The range of the increase was 3.0–5.1-fold in the MPNc and 2.8–5.0 in the MeApd. The 50-μg injections significantly increased and maintained CCK mRNA levels in the MPNc from 12 to 96 h (range of the increase 2.4–4.1-fold) and in the MeApd from 24 to 96 h (range of the increase 2.2–2.8-fold). The repeated administration of 2 μg estrogen induced a significant increase of message levels in the MPNc at 12 and 24 h that were 4.2- and 4.7-fold, respectively. In the MeApd this estrogen treatment did not significantly increase CCK mRNA. These studies demonstrate that small doses (2 μg) of estrogen that mimic the pattern and circulating levels of estrogen dramatically stimulate CCK mRNA levels in the limbic-hypothalamic circuit. To further study this steroid stimulation, ovariectomized female rats were implanted with estradiol-filled cannulae into the bed nucleus of the stria terminalis or MeA. Estrogen elevated CCK mRNA levels locally in each nucleus. Implants in the bed nucleus also elevated CCK mRNA levels in the MeApd indicating that physiologic estrogen stimulation of CCK in the MeApd is the result of both local and distal transsynaptic elevation of CCK mRNA levels. The site-specific induction of CCK mRNA levels within the limbic-hypothalamic nuclei provides another important facet of estrogenic modulation of CCK induction. © 1996 John Wiley & Sons, Inc.  相似文献   
68.
This study tested the hypothesis that the relative proportion of neurons that are hormone sensitive in avian song control nuclei is related to the basic motor ability to sing, whereas the absolute number of such neurons is related to the complexity of song behavior. Either [3H]testosterone (T) or estradiol (E2) was injected into male and female rufous and white wrens (Thryothorus rufalbus), a tropical species in which females sing duets with males but have smaller song repertoires than males. Autoradiographic analysis indicated that there were no sex differences in the proportions of T or E2 target cells in two song nuclei: the high vocal center (HVC) and the lateral portion of the magnocellular nucleus of the anterior neostriatum (IMAN). The density of labeled cells per unit volume of tissue did not differ between the sexes in either song nucleus. Males have larger song nuclei, however, which is consistent with their more complex song behavior, and therefore have a greater total number of hormone-sensitive neurons in these regions than do females. Comparison of these results with measures of hormone accumulation in zebra finches, canaries, and bay wrens supports the hypothesis presented. © 1996 John Wiley & Sons, Inc.  相似文献   
69.
We have compared three competitive chemiluminescent immunoassays (CLIA) for estradiol (E2) using an N-functionalized acridinium ester (AE). The assays were a standard competitive assay using immobilized antibody and directly labeled antigen (type A), an immobilized antibody and indirectly labeled antigen (type B), and an immobilized antigen and labeled antibody (type C). In an antibody-immobilized system, the assay using both AE- and E2-labeled thyroglobulin as a tracer (type B) was more sensitive than that using AE directly coupled with E2 (type A). Subsequently, a comparison of the antibody-immobilized system (type B) and an antigen-immobilized system (type C) showed that the latter was slightly more sensitive than the former. The sensitivity of the CLIA (type C) was similar or superior to commercially available CLIA or radioimmunoassays for E2. Thus, the N-functionalized AE proved to be a useful labeling reagent for a competitive CLIA with high sensitivity.  相似文献   
70.
Triploidy is a viable condition in teleosts. However, in many salmonids, the triploid condition in the female results in sterility as gametogenesis appears to be disrupted. Although the underlying mechanisms regulating the gonadal development of teleosts have not been clearly elucidated, the reversal of phenotypic sex by the administration of the appropriate exogenous steroid during early development supports the argument that gonadal steroids play a pivotal role in sexual differentiation and subsequent gonad development in these fish. To determine whether the failure of normal ovarian development in triploid female rainbow trout (Oncorhynchus mykiss) is due to an absence or reduction of endogenous sex steroids, ovarian morphology was compared between diploid and triploid juvenile rainbow trout treated with exogenous estradiol-17β (E2). The ovaries of both untreated and E2 treated diploid fish, at 145 days post-fertilization, contained synchronously developing oocytes in the perinucleolar stage, whereas ovaries from untreated and estradiol-treated triploid fish of the same age were considerably smaller and devoid of developing oocytes. No differences in the ovaries of triploid untreated fish and triploid fish treated with E2 were observed. It is reported that exposure to exogenous E2 during the period of gonadal differentiation is not sufficient to induce oocyte development in triploid rainbow trout. © 1996 Wiley-Liss, Inc.  相似文献   
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