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81.
From a cohort of women treated for preterm labor at the Swedish Hospital Medical Center for a 1-year period, 58 patients were identified as receiving one or more tocolytic agents. Twenty-seven of the 58 patients met study criteria for the determination of the effects of tocolytic therapy on amniotic fluid volume both before and during treatment by means of ultrasound examination. Fourteen of 17 patients (82.3%) treated with nonsteroidal anti-inflammatory drugs demonstrated a decrease in amniotic fluid, whereas none of the 10 patients treated with other tocolytic agents experienced a decrease in fluid volume. Decreased amniotic fluid associated with nonsteroidal anti-inflammatory drug treatment was reversible in seven of eight patients when treatment was discontinued and ultrasound examinations were performed after treatment.  相似文献   
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The potential utility of screening for femur length shortening in prenatal detection of Down syndrome (trisomy 21) was evaluated by comparing 49 consecutive fetuses with Down syndrome with 572 chromosomally normal fetuses before genetic amniocentesis. Ratios of measured femur length/predicted femur length and biparietal diameter/femur length were calculated for each fetus. The predicted femur length was calculated from a regression equation relating the biparietal diameter and femur length derived from a sample control group. With this normal regression equation, 7 of 49 (14.3%) fetuses with Down syndrome had short femur lengths (measured femur length/predicted femur length ratio of less than or equal to 0.91) compared with 35 of 572 (6.1%) fetuses with a normal karyotype (p less than 0.05). However, the maximum positive predictive value for identification of Down syndrome based on short femur lengths was only 0.93% for a high-risk population (prevalence of Down syndrome, 1:250) and 0.33% for a low-risk population (prevalence of Down syndrome, 1:700). We conclude that ultrasonographic screening of short femur length is less effective for prenatal detection of Down syndrome than initially suggested.  相似文献   
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Urban air pollution and lung cancer in Stockholm   总被引:31,自引:0,他引:31  
We conducted a population-based case-control study among men 40-75 years of age encompassing all cases of lung cancer 1985-1990 among stable residents of Stockholm County 1950-1990. Questionnaires to subjects or next-of-kin (primarily wives or children) elicited information regarding smoking and other risk factors, including occupational and residential histories. A high response rate (>85%) resulted in 1,042 cases and 2,364 controls. We created retrospective emission databases for NOx/NO2 and SO2 as indicators of air pollution from road traffic and heating, respectively. We estimated local annual source-specific air pollution levels using validated dispersion models and we linked these levels to residential addresses using Geographical Information System (GIS) techniques. Average traffic-related NO2 exposure over 30 years was associated with a relative risk (RR) of 1.2 (95% confidence interval 0.8-1.6) for the top decile of exposure, adjusted for tobacco smoking, socioeconomic status, residential radon, and occupational exposures. The data suggested a considerable latency period; the RR for the top decile of average traffic-related NO2 exposure 20 years previously was 1.4 (1.0-2.0). Little association was observed for SO2. Occupational exposure to asbestos, diesel exhaust, and other combustion products also increased the risk of lung cancer. Our results indicate that urban air pollution increases lung cancer risk and that vehicle emissions may be particularly important.  相似文献   
84.
The aim of this study was to measure plasma atrial natriuretic peptide in preterm infants with a patent ductus arteriosus before and after closure with indomethacin. Atrial natriuretic peptide was measured in 28 preterm infants with clinical and echocardiographic evidence of a patent ductus arteriosus and in eight preterm infants who did not develop clinical evidence of a patent ductus arteriosus. Plasma concentration of atrial natriuretic peptide was measured by radioimmunoassay. In 18 infants the patent ductus arteriosus closed after one course of indomethacin; atrial natriuretic peptide levels decreased from median 1240 pg/ml (range 201-5483 pg/ml) to 266 pg/ml (range 62-1108 pg/ml). In four infants the patent ductus arteriosus closed after two courses of indomethacin and two infants had surgical ligation after indomethacin treatment failed. The patent ductus arteriosus closed spontaneously in four infants (atrial natriuretic peptide median level 152 pg/ml, range 61-495 pg/ml). In the eight infants without patent ductus arteriosus, atrial natriuretic peptide level was median 224 pg/ml (range 38-876 pg/ml). Measurement of plasma atrial natriuretic peptide concentration has a role in predicting when indomethacin treatment is indicated.  相似文献   
85.
Upper respiratory tract infection (URTI) is a common cause of deterioration of asthma in children. We investigated if inhaled steroids (budesonide), started early after URTI, could reduce asthma. Thirty-one children, 3-10 years of age, with deterioration during URTI participated. The study design was double-blind, crossover and placebo-controlled. Peak-expiratory flow (PEF) and symptom scores were recorded. Four treatment periods of 9 days, two with budesonide and two with placebo, were planned. Treatment was started at the first sign of URTI. Budesonide/placebo was given by Turbuhaler at 0.2 mg qid for 3 days, tid for 3 and bid for the last 3 days. Twenty-two children completed 67 periods. Eleven visited the emergency room, only three during budesonide therapy. Five received oral steroids and two where admitted to hospital, all receiving placebo. Symptom scores were not significantly lower during budesonide treatment. PEF, both morning and evening, was significantly higher during budesonide than placebo (p = 0.015 and p = 0.022). Inhaled budesonide can attenuate exacerbation of URTI-induced asthma. Asthma, budesonide, infection, inhaled steroids, intermittent, prophylactic
J Svedmyr, Department of Paediatrics, Falu Hospital, S-791 82 Falun, Sweden  相似文献   
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PURPOSE/METHODS: Serpiginous choroiditis is a rare, chronic, progressive, and recurrent bilateral disorder primarily involving the choriocapillaris and the retinal pigment epithelium. Progression typically occurs as pseudopodia extensions away from the optic discs and usually infringes upon the macula and foveal region. RESULTS/CONCLUSIONS: We studied three cases of geographic choroidopathy, showing the ophthalmoscopic picture and the fluorescein angiographic of the fundus oculi, characterised by typical disease lesions. Finally, some considerations in differential diagnosis between pigment epithelium inflammatory diseases will be reported.  相似文献   
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