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991.
Dimeric inhibins, activins, and follistatin (FS) were all initially characterized as reproductive endocrine hormones that regulate follicle-stimulating hormone (FSH) secretion. This model, however, has expanded under the weight of current medical evidence. Activin appears to play a central auto/paracrine role in reproductive and nonreproductive tissues. Inhibin and FS each have important counterregulatory functions in activin signaling. With reproductive aging, inhibin B declines along with the follicular pool and disturbs the dynamics of the normal menstrual cycle of midreproductive age. The loss of inhibin restraint of FSH secretion appears to be the initiating endocrine event that leads to menstrual cycle shortening and some of the hormonal unpredictability of the late reproductive years. It may also be related to the decline in fertility that occurs in reproductive aging. In men, inhibin B is an excellent marker for gonadal competence, and the decline of inhibin B with age reflects decreased gonadal reserve in both sexes. Circulating activin increases with aging, but its effect on reproduction in women and men is not clear. FS does not appear to change greatly with aging in men or women. The age-related fluctuations in this delicately balanced regulatory triad influence reproductive capacity and the sequelae of chronological aging. Elucidation of the molecular pathways responsible for the action of these hormones may allow closer integration with their current conceptual roles in aging. 相似文献
992.
AIMS: While hydralazine is commonly used as monotherapy in animal studies, its potential side effects are seldom acknowledged. Purported side effects occur from sympathetic and renin-angiotensin system activation, and include tachycardia, oedema, and nausea. We hypothesized that these side effects would alter body composition by increasing body water and/or decreasing body fat. METHODS: Female New Zealand White rabbits were divided into lean and obese control and hydralazine-treated groups. Lean rabbits ate a maintenance diet for 12 weeks; obese rabbits ate an ad lib high fat diet. Hydralazine was administered at 6 and 10-14 mg kg(-1) day(-1) for lean and obese hydralazine groups, respectively. Body composition was determined using triplicate 2-3 g samples of whole body homogenate, and analysed using 2 x 2 ANOVA for diet vs. hydralazine effects. RESULTS: Hydralazine-treated animals had lower body fat (15.7 +/- 1.1 and 21.8 +/- 1.0%, respectively) and higher body water (59.8 +/- 0.8 and 55.4 +/- 0.6%, respectively) compared with controls. While obese controls were heavier than obese hydralazine-treated animals (5.12 +/- 0.09 vs. 4.73 +/- 0.11 kg, respectively) and had greater overall feed consumption (13.5 +/- 0.4 vs. 11.8 +/- 0.4 kg, respectively), a subsequent analysis using subsets that did not differ in body weight or feed consumption yielded the same conclusions. Plasma adrenaline and noradrenaline did not differ between control and hydralazine-treated groups. CONCLUSIONS: Use of hydralazine to control blood pressure alters body composition. Direct or indirect effects of hydralazine may impact physiological systems under study. Alterations in adipose tissue may be of particular concern because of its endocrine function. 相似文献
993.
994.
995.
Congenital heart disease is one of the most common congenital malformations diagnosed in liveborns. As more women undergo prenatal diagnosis, the need for screening fetal echocadiography increases. The fetal, maternal, and familial indications for fetal echocadiography are outlined in order to improve the identification of women in greatest need for this screening modality. 相似文献
996.
997.
Ying MS Fuller J Young J Marcus DM 《Journal of pediatric ophthalmology and strabismus》2004,41(6):358-360
We report a congenital neurosensory retinal detachment associated with an optic nerve coloboma with subsequent spontaneous reattachment. This represents the earliest reported case of such a clinical situation. An observation period is recommended for infants with this clinical course to allow for the opportunity of spontaneous reattachment. 相似文献
998.
999.
Taha TE Kumwenda N Kafulafula G Kumwenda J Chitale R Nkhoma C Katundu P Mukiibi J Chen S Hoover D Broadhead R 《Annals of tropical paediatrics》2004,24(4):301-309
We assessed the safety of short-term antiretroviral prophylaxis to prevent mother-to-child transmission (MTCT) of HIV by monitoring haematological changes in children up to the age of 18 months. Babies of HIV-infected women were randomised at birth to receive a single dose of nevirapine (NVP) alone or with zidovudine (ZDV) twice daily for a week. Based on the time of presentation to the labour ward, mothers of these babies might or might not have received intrapartum NVP. Complete blood counts were performed at birth and at 1.5, 3, 6, 9, 12, 15 and 18 months. Babies' HIV status was determined by HIV-1 RNA testing. A total of 1755 babies were included in the study. Age-specific mean haemoglobin levels and prevalence of anaemia (haemoglobin < 10 g/dL) were not significantly different in cases where only the babies received a single dose of NVP and cases where NVP was given to mother/infant pairs or additional ZDV to the baby. Among HIV-infected children compared with uninfected children, the age-specific frequency of anaemia was significantly greater, anaemia started earlier and recovery to normal levels was slower and prolonged. A reversible granulocytopenia was observed in all children between 1.5 and 3 months of age. HIV infection significantly increased the children's risk of death. Antiretroviral prophylaxis appeared to protect against anaemia and child death. Short regimens of antiretrovirals to prevent MTCT of HIV are not associated with long-term adverse haematological changes. 相似文献
1000.
Shah SS Metlay JP 《Archives of pediatrics & adolescent medicine》2004,158(10):1018; author reply 1018