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61.
A cohort of 1163 pregnant women in two small towns in South Wales, UK, was identified and followed until the children born to them were five years of age. Growth in these children is described and a number of determinants identified. Social-class differences were very small at birth but differences in height became clear by the age of two years and in head circumference before this. In height the differences were largely accounted for by greater growth in social class I, but there was a gradient in head circumference throughout all the social classes. The social class effects gradually increased as the children became older. Parity of the mothers had a small effect on size at birth but age of the mother had no effect once parity was allowed for. Data on illnesses in the children were collected but no effect on growth could be detected. By far the most important determinant of growth which could be controlled is maternal smoking. About 40% of the women smoked, about 17% heavily (15 or more cigarettes per day) and the prevalence of smoking altered little during pregnancy. There was a graded effect of smoking on growth up to a 9% deficit in birth-weight, a 2% deficit in length at birth and a 1.5% deficit in head circumference in the babies born to the mothers who smoked most heavily (25 or more cigarettes per day) compared with non-smokers. There effects decreased with age but there were still residual effects at age five years. 相似文献
62.
After admission to hospital for bed rest, 200 women with multiple pregnancies were randomly allocated to receive either 4 mg of salbutamol orally five times daily, or to receive no drug. After an average of 6 weeks treatment, no difference between the experimental groups could be detected with respect to duration of gestation, birthweight or any other of the outcomes of pregnancy observed. 相似文献
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P M Doraiswamy K R Krishnan O B Boyko M M Husain G S Figiel V J Palese P R Escalona S A Shah W M McDonald W J Rockwell 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(3):351-356
1. The frequent occurrence of hypothalamo-pituitary dysfunction in patients with eating disorders as well as prior reports that nutritional and endocrine status influence pituitary morphology, led us to hypothesize that pituitary size and shape may be altered in patients with eating disorders. 2. Magnetic resonance imaging (MRI) does not use ionizing radiation and is currently one of the most feasible modalities available to study the pituitary gland in vivo. Using MRI, we have previously reported in a preliminary study that female patients with eating disorders had significantly smaller pituitary glands than controls. In addition MRI excluded any pituitary mass lesions. 3. In this report, we confirm our previous MRI findings and provide further evidence of pituitary abnormalities in an expanded sample of eating disorder patients. Preliminary data on pituitary volume estimates from MRI scans are provided for a subset of patients and controls. 相似文献
67.
This paper is an attempt to assess the relevance of the inhibitors of fibrinolysis for clot lysis in selected disease states and to discuss the mechanisms leading to acquired abnormal levels of such inhibitors. When compared to 20 control subjects the 30 hypertriglyceridemic patients (14 with type IIb and 16 with type IV) displayed significantly (p less than 0.001) increased plasma plasminogen activator inhibitor (PAI) activity (221 +/- 88% and 290 +/- 104% respectively; mean +/- SD), moderately (p less than 0.01) increased alpha 2 antiplasmin (alpha 2AP) level (112 +/- 11% and 115 +/- 16%) and accordingly an obviously prolonged dilute blood clot lysis time (DBCLT). Neither PAI activity and alpha 2AP level nor DBCLT were significantly different from controls in the 10 patients with hyperlipoproteinemia type IIa. The 18 patients with severe hepatic cirrhosis had low alpha 2AP level (59 +/- 19.7%) and accelerated clot lysis, while mean PAI activity (160 +/- 87%) was slightly (p less than 0.05) increased. In the 17 nephrotic patients alpha 2AP was increased (115 +/- 12%) while PAI activity was similar to controls and DBCLT rather shorter. Two liver secretion enzymes, namely serum cholinesterase and plasma protein C, were found to be decreased in cirrhotic patients, similar to control values in hyperlipoproteinemia type IIa and obviously increased in nephrotic patients as well as in hypertriglyceridemic subjects. The relevance of PAI and alpha 2AP for clot lysis was considered in relation to data in the literature concerning the behaviour of t-PA and factor XIII.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Assessment of caffeine exposure: caffeine content of beverages, caffeine intake, and plasma concentrations of methylxanthines 总被引:4,自引:0,他引:4
The caffeine content of all tea or coffee beverages consumed by 17 healthy adults over 24 hours was measured. Plasma caffeine, theophylline, theobromine, and paraxanthine concentrations were determined over the same 24 hours. The average caffeine content per drink was 60.4 +/- 21.8 mg for instant coffee (14-fold range), 80.1 +/- 19.2 mg for brewed coffee (2.8-fold range), and 28.8 +/- 13.7 mg for tea (5.5-fold range). The number of drinks of coffee and tea consumed was a poor index of actual caffeine intake (r2 = 0.42). Caffeine intake correlated poorly with the 24-hour average caffeine concentration (r2 = 0.41), but there was a very good correlation between a single plasma caffeine concentration measured at 5 PM and the 24-hour average concentration (r2 = 0.94). The same was true for paraxanthine (r2 = 0.86). Paraxanthine accounted for 67.3% of the total dimethylxanthines in plasma, while theobromine and theophylline accounted for 24.4% and 8.3%, respectively. Mean caffeine clearance was 1.2 +/- 0.3 ml/min/kg. Plasma caffeine concentration before the first drink in the morning correlated very poorly with caffeine clearance (r2 = 0.07), even when adjusted for caffeine intake (r2 = 0.21). 相似文献
70.