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Energy expenditure was measured during pregnancy in seven primigravid women at 12-15, 25-28, and 34-36 weeks and after the cessation of lactation. On each occasion the resting metabolic rate and the increase in metabolic rate after ingestion of a liquid test meal were measured by indirect calorimetry. In absolute terms the resting metabolic rate increased steadily during pregnancy but when expressed per unit of body weight no change was found. The energetic response to a mixed constituent meal was significantly reduced by 28% in the middle trimester of pregnancy. These findings suggest a possible maternal adaptation to increase energetic efficiency at a time when the energy demands of the fetus are high. 相似文献
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J Howie 《BMJ (Clinical research ed.)》1987,294(6575):820-821
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J.H. Kennedy M.A. Quinn P.W. Howie A.A. Calder 《Prostaglandins & other lipid mediators》1978,15(1):169-173
A viscous suspension of prostaglandin E2 was introduced endocervically to induce labor in patients with favourable induction features. The method was found to be effective and compared favourably with the conventional practices of amniotomy and intravenous oxytocin infusion or oral prostaglandin therapy. Several advantages were found including a high degree of patient acceptability. 相似文献
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OBJECTIVE--To evaluate the effectiveness of biochemical screening of individual pregnancies for Down''s syndrome risk. DESIGN--Retrospective determination of risk. SETTING--Obstetric and cytogenetic services in Tayside, Scotland. SUBJECTS--3436 pregnant women who had screening for neural tube defects in the second trimester during November 1988 to March 1990 and whose pregnancies were dated by ultrasonography. Three women with pregnancies associated with Down''s syndrome reported later in 1990. MAIN OUTCOME MEASURES--Individual risk calculated from age at estimated date of delivery; chorionic gonadotrophin and alpha fetoprotein concentrations in serum samples obtained at precisely determined gestational ages in second trimester. Results of karyotype determination and outcome of pregnancy. RESULTS--During November 1988 to March 1990 karyotypes were determined for 5% of pregnancies for reasons of maternal age and genetic history and one of the eight affected fetuses was detected. Individual risk could not be calculated for 347 pregnancies, but screening on this basis would have detected five of the cases and required screening in 194 out of 3089 (6.3%) pregnancies; all three affected pregnancies reported later in 1990 would also have been detected, giving a success rate of 73% (95% confidence interval 39% to 94%). The age distribution of women according to individual risk suggests that women over 35 would be screened effectively. CONCLUSION--Screening based on individual risk would use resources more effectively than screening based on maternal age and genetic history without affecting detection rates in older women. 相似文献
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J W Howie 《BMJ (Clinical research ed.)》1979,2(6202):1411-1412