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51.
OBJECTIVE: The effect of hormone replacement therapy (HRT) on cardiovascular risk is intensely debated. The aim of this study was to investigate the long-term effects of HRT given for a few years on all-cause and cardiovascular mortality and the severity of atherosclerosis. METHODS: This analysis was based on a cohort of 1,458 postmenopausal women (55.8 +/- 6.1 years old) who previously participated in a number of randomized, placebo-controlled, clinical trials assessing the efficacy of 2-3 years of therapy with various estrogen plus progestin combinations for preventing bone loss. Women were followed on average for 9.8 years and came for a follow-up visit. Outcome variables were all-cause and cardiovascular mortality and the severity of atherosclerosis, as estimated by semi-quantitative scoring of vascular calcification in the lumbar aorta on lateral radiographs. RESULTS: A total of 174 women died during the observation period. All-cause mortality was decreased by 30% in the HRT+ group compared with the HRT- group (hazard ratio (HR) 0.70; 95% confidence interval (CI) 0.50-0.97) after adjusting for age, body mass index and smoking. Under the same conditions, similar results characterized mortality from cardiovascular disease (n = 61 deaths; 35.1% of all deaths) and coronary heart disease (n = 39 deaths; 22.4% of all deaths), which were decreased by 46% (HR 0.54, 95% CI 0.29-0.98, p = 0.045) and 53% (HR 0.47, 95% CI 0.21-1.03, p = 0.062), respectively. Furthermore, the mean severity score of aortic calcification at follow-up was significantly lower in hormone-treated compared to non-treated women (p < 0.0001). CONCLUSION: Women who receive 2-3 years of HRT after menopause do not have increased all-cause mortality, and results of the present study suggest relative cardiovascular benefits compared to those who had not used hormones.  相似文献   
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BACKGROUND: Leptin is a key regulator of satiety; and the serum concentration is considered to reflect nutritional status. Expressed predominantly by the adipocytes, leptin is also expressed in placenta, which is a major source of both leptin and the leptin receptor in pregnancy serum. As a placenta protein, leptin serum concentrations may be perturbed in Down syndrome (DS) pregnancies as seen for pregnancy-associated plasma protein-A (PAPP-A) and human chorionic gonadotrophin-beta (hCGbeta). We examined whether leptin is a maternal serum marker for foetal DS in the first trimester. MATERIALS AND METHODS: Serum samples from 44 pregnant women with a DS foetus, and 135 control pregnant women in week 8 to 14 had the leptin concentration determined by immunoassay and the concentrations were converted into multiples of the median (MoM) of controls based on log-regression analysis. The distributions of log10 MoM leptin was compared in DS and control pregnancies. RESULTS: Serum leptin increased significantly with gestational age in controls (p = 0.02). The mean log10 MoM in controls was - 0.0486, with a median empirical MoM of 0.89, and - 0.0618, with a median empirical MoM of 0.80, in DS pregnancies. This difference was not significant. The log10 MoM leptin values in DS pregnancies did not change with gestational age (p = 0.32). CONCLUSION: Leptin is not a first-trimester marker for foetal DS.  相似文献   
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OBJECTIVE: To establish the relationship between the first-trimester screening markers [pregnancy-associated plasma protein A (PAPP-A), free human chorionic gonadotrophin-beta (beta-hCG), nuchal translucency (NT)], the Down syndrome (DS) risk estimate, and the adverse outcomes such as low birth weight, small for gestational age (SGA) and pre-term delivery. METHODS: A retrospective cohort study including 1,734 non-selected singleton pregnancies consecutively enrolled into the programme of first-trimester combined screening for DS in a 12-month period at a single centre. Data from the Prenatal Patient Registry in ASTRAIA were combined with the Danish National Newborn Screening Registry and Danish Birth Registry. RESULTS: There was a significant relation between low PAPP-A MoM, low beta-hCG MoM, increased risk estimate for DS and low birth weight and SGA. Low PAPP-A MoM and increased NT showed a significant relation to pre-term and spontaneous pre-term delivery. Low PAPP-A MoM showed a significant relation to early pre-term delivery. CONCLUSION: First-trimester screening markers exhibited a significant relation to low birth weight, SGA and to some extent, to pre-term and early pre-term delivery. The screening performance of individual markers was poor.  相似文献   
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BACKGROUND: First-trimester maternal serum screening for Down syndrome (DS) can be improved by the use of additional serum markers. We examined whether progesterone (P), synthesized by placenta, might be a first-trimester maternal serum marker for fetal DS. MATERIALS AND METHODS: P was quantified in first-trimester maternal serum from 42 DS, six trisomy 18 and two trisomy 13 pregnancies and 115 controls. Log-regression of P versus gestational age in days was used to convert P concentrations into multiples of the median (MoM). RESULTS: The P concentrations in controls increased with gestational age (p = 9.5 x 10(-7)). The log10MoM P distribution in DS pregnancies was not significantly different from that in controls. However, from day 58-67, the log10MoM P was elevated in DS pregnancies (n = 10) with a mean (SD) of 0.1040 (0.0956), compared to a mean (SD) of - 0.0109 (0.1661) in controls (n = 24) (p = 0.05). Five out of six trisomy 18 and both trisomy 13 pregnancies had a P MoM < 1. CONCLUSION: P is not a useful marker for DS in first trimester, except perhaps in a narrow gestational age window from day 58 to 67. P is a trisomy 18/13 marker.  相似文献   
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Examinations of 83 patients and 13 healthy subjects with the augmented histamine test and gastric biopsy show that a maximal acid secretion lower than 10 mEq HCl/hour signifies a diffuse gastritic lesion, the type of which can be verified by a single gastric biopsy. Detailed investigations of the nature and clinical course of gastritis, however, require repeated tests of gastric function and multiple gastric biopsies.  相似文献   
60.
Decreased uroporphyrinogen decarboxylase (UROD) activity is a characteristic feature of the most common of the porphyrias, porphyria cutanea tarda (PCT). A subgroup of the clinically overt PCT cases is associated with mutations in the gene encoding UROD and inherited as an autosomal-dominant trait. In this study, DNAs from 53 Danish PCT patients were subjected to genetic analysis for UROD mutations using denaturing gradient gel electrophoresis. Eleven genetic variations, seven of which are possible disease causing, were identified. All but one of these mutations were previously unknown, lending further support to the assumption that PCT is a heteroallelic disease. Only 11% of the examined patients were previously recognized as familial PCT cases. However, possible disease-related UROD mutations were identified in 24% of the examined patients, indicating that genetic analysis of PCT patients may improve differentiation between familial and sporadic PCT cases.  相似文献   
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