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OBJECTIVES: To characterize ovarian morphology in a group of ovulatory, non-hirsute women with infertility and normal circulating levels of gonadotropins and sex steroids. METHODS: Thirty-three women with normal physical examinations, regular ovulatory menses, and absence of hirsutism (Ferriman-Gallwey score < or = 7) were studied. No woman had thyroid disease, galactorrhea, polycystic ovary syndrome, 21-hydroxylase deficiency or diabetes. Two-dimensional (2D) transvaginal sonography (TVS) was used to measure follicle size and ovarian volume on menstrual cycle day 5. Three-dimensional (3D) TVS images were stored to determine the number of follicles (measuring 2-10 mm in diameter) in the largest sonographic plane. Fasting blood sampling and oral glucose tolerance testing were performed to assess serum gonadotropin and sex steroid levels as well as glucose tolerance. RESULTS: The median ovarian volume by 2D-TVS imaging was 7.2 (range, 2.3-15.8) cm(3) (n = 64 ovaries). No follicles were > 10 mm in diameter. The median number of follicles by 3D-TVS was 4 (range, 2-8) (n = 63 ovaries) in the largest sonographic plane. Fourteen of 63 ovaries (22%) had six or more small follicles in one plane distributed within normal stroma (multifollicular ovary, MFO). No ovary had 10 or more follicles in one plane located within abundant stroma (polycystic ovary). Of 33 women examined, 20 women (61%) had apparently normal ovaries bilaterally, while 13 (39%) had at least one MFO. There were no significant differences between women with and those without MFO in serum gonadotropin and steroid levels or glucose tolerance. CONCLUSIONS: MFO is a common morphological variant in non-hirsute ovulatory women with normal gonadotropin secretion and ovarian steroidogenesis.  相似文献   
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Subcortical laminar heterotopia (SCLH), or 'double cortex', is a cortical dysgenesis disorder associated with a defect in neuronal migration. Clinical manifestations are epilepsy and mental retardation. This disorder, which mainly affects females, can be inherited in a single pedigree with lissencephaly, a more severe disease which affects the male individuals. This clinical entity has been described as X- SCLH/LIS syndrome. Recently we have demonstrated that the doublecortin gene, which is localized on the X chromosome, is implicated in this disorder. We have now performed a systematic mutation analysis of doublecortin in 11 unrelated females with SCLH (one familial and 10 sporadic cases) and have identified mutations in 10/11 cases. The sequence differences include nonsense, splice site and missense mutations and these were found throughout the gene. These results provide strong evidence that loss of function of doublecortin is the major cause of SCLH. The absence of phenotype-genotype correlations suggests that X-inactivation patterns of neuronal precursor cells are likely to contribute to the variable clinical severity of this disorder in females.   相似文献   
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We have used a mouse model to study the ability of human CFTR to correct the defect in mice deficient of the endogenous protein. In this model, expression of the endogenous Cftr gene was disrupted and replaced with a human CFTR cDNA by a gene targeted 'knock-in' event. Animals homozygous for the gene replacement failed to show neither improved intestinal pathology nor survival when compared to mice completely lacking CFTR. RNA analyses showed that the human CFTR sequence was transcribed from the targeted allele in the respiratory and intestinal epithelial cells. Furthermore, in vivo potential difference measurements showed that basal CFTR chloride channel activity was present in the apical membranes of both nasal and rectal epithelial cells in all homozygous knock-in animals examined. Ussing chamber studies showed, however, that the cAMP-mediated chloride channel function was impaired in the intestinal tract among the majority of homozygous knock-in animals. Hence, failure to correct the intestinal pathology associated with loss of endogenous CFTR was related to inefficient functional expression of the human protein in mice. These results emphasize the need to understand the tissue- specific expression and regulation of CFTR function when animal models are used in gene therapy studies.   相似文献   
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Preimplantation genetic diagnosis was performed in 61 day 3 embryos obtained by in-vitro fertilization from seven patient carriers of haemophilia, Marfan's syndrome, Bloch-Sulzemberg syndrome (incontinentia pigmentosa) or X chromosome-linked immune deficiency, retinitis pigmentosa, and FG syndrome, which is characterized by mental retardation and hypotonia. After multiplex polymerase chain reaction, 16 embryos were diagnosed as being unaffected, and these were transferred to the uterus on the following day (day 4). Of these embryos, six (37.5%) implanted, resulting in the delivery of a singleton and a twin pregnancy, a late second trimester miscarriage (twins at week 20) and a first trimester miscarriage at week 8. All the diagnoses were confirmed by amniocentesis. We report for the first time a late day 4 transfer of biopsied human embryos undergoing preimplantation genetic diagnosis. This transfer schedule allows an extra day to perform genetic analyses on single blastomeres and to monitor any adverse effect of the biopsy procedure.   相似文献   
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