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61.
Emergent cerclage may be defined as that performed in the setting of advanced cervical dilation with bulging or "hourglass" membranes. During a five year period, 15 patients with bulging or hourglass membranes and marked cervical dilation in the second trimester were treated with emergent cerclage. Included were two triplet gestations. Complications were limited to intraoperative rupture of fetal membranes in two patients and chorioamnionitis either in the early postoperative period (two) or later in pregnancy (three). Pregnancy was prolonged for a sufficient time to deliver viable fetuses in 11 of 15 patients. Eleven of 13 neonates of a gestational age of 24 weeks or more survived. The lack of significant maternal morbidity combined with the results for the fetus-infant supports further efforts in this area.  相似文献   
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The effect of hypertension in pregnant women on fetal maturation is an issue of considerable importance. Because of a possible role of prolactin in fetal adrenal steroidogenesis and in fetal lung maturation, we have investigated the relationship between hypertension in pregnant women and levels of prolactin and dehydroepiandrosterone sulfate in serum of newborn infants. It was found that with the mild-to-moderate form of pregnancy-induced hypertension (PIH), there was little effect on prolactin levels in newborn serum. In newborns of women with severe PIH, however, serum prolactin levels were significantly greater (p less than 0.01) than those in newborns of women with uncomplicated pregnancies. Conversely, umbilical serum concentrations of dehydroepiandrosterone sulfate in newborns of women with severe PIH were significantly less (p less than 0.05) than those in newborns of women with uncomplicated pregnancies. These findings are supportive of the view that pituitary function and adrenocortical function of fetuses of women with PIH are different from those of fetuses of normotensive women. These findings are suggestive that PIH alters the function of the fetal pituitary and adrenal cortex.  相似文献   
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Test and evaluation of exercise-enhanced preoxygenation in U-2 operations   总被引:1,自引:0,他引:1  
BACKGROUND: Preoxygenation to prevent decompression sickness (DCS) during U-2 reconnaissance flights requires considerable time and occasionally does not provide adequate protection. Increasing preoxygenation within a practical period of time provides marginally increased protection and is not always operationally feasible. Including exercise during preoxygenation to increase muscle tissue perfusion, cardiac output, and ventilation can improve the quality of the denitrogenation. METHODS: A pilot, who reported two cases of DCS during his first 25 U-2 high flights involving cabin altitudes of 29,000-30,000 ft, volunteered to test exercise-enhanced preoxygenation. He performed 10 min of strenuous upper and lower body exercise at the beginning of preoxygenation prior to subsequent high flights without increasing total preoxygenation time. RESULTS: The exercise was performed at 75% of maximal oxygen uptake based on the estimated maximal oxygen uptake determined during an Air Force aerobic fitness test and heart rate. The pilot's next 36 high flights, using exercise-enhanced preoxygenation, were completed with no reports of DCS. CONCLUSIONS: This statistically significant operational test reinforced the laboratory studies. Implementation of this procedure for reducing DCS in susceptible U-2 pilots and collecting additional data from the U-2 pilot population is recommended.  相似文献   
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Although renal abnormalities have been described in children with Alagille's syndrome, cystic kidney disease has not often been documented, and then usually only at necropsy. Three children with Alagille's syndrome are described, in two of whom a unilateral multicystic dysplastic kidney was detected by prenatal ultrasound; in the other, a solitary cortical cyst was found later in childhood. All have normal renal function, growth, and liver synthetic function but continue to have clinical and biochemical signs of cholestasis. These cases show that unilateral cystic kidney disease with or without renal dysplasia may be associated with Alagille's syndrome, that the clinical course is not necessarily unfavourable, and that Alagille's syndrome should be included in the differential diagnosis of cystic kidney disorders associated with cholestatic liver disease. Patients with Alagille's syndrome should be evaluated by renal ultrasound.  相似文献   
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This study reports the use of pelvic ultrasound scanning in childhood onset anorexia nervosa. The aim was to determine the weight and weight for height ratio (wt/ht) that would correspond with ovarian and uterine maturity and therefore offer the optimal opportunity for the start or resumption of menstruation. On initial assessment, all children had mean weight, wt/ht, ovarian and uterine volumes significantly below expected. At follow up, half the children had started or resumed menstruation. When compared with those who had persisting amenorrhoea, the recovered children had a significantly higher mean weight (48.4 kg v 43.8 kg), mean wt/ht (96.5% v 87.5%), mean ovarian volume (6.2 ml v 4.9 ml), and mean uterine volume (14.6 ml v 10.8 ml). The study indicates that conventional target weight and wt/ht in anorexia nervosa may be too low to ensure ovarian and uterine maturity, and that pelvic ultrasound, which is well tolerated by this group of children, is a useful addition to their management.  相似文献   
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