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81.
In a prospective hospital based study, during the period from Jan 95 to Dec 96, 3100 consecutively delivered live newborns were studied for the incidence of low birth weight neonates and to evaluate the associated risk factors. One thousand fourteen newborns were classified as low birth weight babies. The incidence expressed per 1000 live births was 327 (32.7%). Of these, 815 (80.4%) were small for gestational age neonates and 199 (19.6%) were preterm neonates. Five hundred seventy small for gestational age neonates (70%) were weighing between 2001 to 2500 gms. Mothers belonging to the age group of 19-25 years delivered the maximum number of low birth weight babies (618/1014) and of these 82.8% were small for gestational age neonates. There were 48 neonates with low birth weight born to mothers below the age of 18 years. Primiparous mothers were found to contribute higher number of low birth weight neonates (414/1014). Spacing as a factor did not show any major difference. Two hundred sixty two low birth weight neonates were born to mothers with significant obstetrical problems such as pregnancy induced hypertension, bad obstetrical history and premature rupture of membranes. The incidence of 32.7% of low birth weight babies is high enough to ring alarm bells.  相似文献   
82.
We analyzed baseline and 12-month follow-up interview data from 98 women who had volunteered to use an experimental intracervical device (ICD) and from 155 women who had been randomly assigned to two control groups, the levonorgestrel-releasing intrauterine device (LNG-IUD; N = 86) and the copper Nova-T IUD (N = 69). All participants were clinic patients in Helsinki, Finland. Initial analysis of 12-month discontinuation data indicated that a significantly higher percent of ICD users (22.4) discontinued their device than did either LNG-IUD (7.0) or Nova-T (8.7) users. However, we were no longer able to detect significant differences in discontinuation after controlling for baseline variables that assessed predisposition to be dissatisfied with contraception in general. Adjusted probabilities of discontinuing the ICD, LNG-IUD, and Nova-T were 11.8%, 6.2% and 7.9%, respectively. These data indicate that the ICD is likely to be acceptable to Helsinki clinic patients; moreover, they suggest a definite place for hormonal intrauterine devices in the contraceptive armamentarium. Most importantly, the methodology used here can be generalized to acceptability studies of other contraceptive devices and drugs undergoing Phase I and early Phase II clinical trials (in situations where randomization may not be feasible) in order to identify and control for the bias introduced by nonrandom assignment procedures.  相似文献   
83.
Low serum albumin and low serum cholesterol levels are among the most consistent predictors of mortality in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Hypoalbuminemia is often interpreted as a marker of poor nutrition, but serum albumin and cholesterol levels can also be low as part of a cytokine-mediated acute-phase reaction to acute or chronic inflammation. Here we report the results from a 900-day prospective study designed to determine whether tumor necrosis factor-alfa (TNF-alpha) and interleukin-6 (IL-6) predict serum albumin and cholesterol levels and mortality in a group of 90 ambulatory, adult hemodialysis patients with no acute infection, hospitalization or surgery, and no known acquired immunodeficiency syndrome (AIDS), malignancy, or liver disease. Measurable levels of TNF-alpha and/or IL-6 were found in 89 of 90 patients. Significant relationships were found between TNF-alpha and IL-6 and the degree of hypoalbuminemia and dyslipoproteinemia. IL-6 was the strongest predictor of mortality in univariate and multivariate analysis, followed by age, albumin level, and body mass index (BMI). Although the cause of hypercytokinemia was not addressed in this study, the data support the view that hypoalbuminemia and hypocholesterolemia are negative acute-phase responses to inflammatory stimuli. These results suggest that efforts to identify the nature of the stimuli for cytokine production and to lower cytokine levels in hemodialysis patients might be effective in improving the survival of patients undergoing hemodialysis.  相似文献   
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Magnetocardiographic mapping was performed on a 2-year-old boy who suffered from the Wolff-Parkinson-White syndrome in association with a complex congenital heart defect. The pre-excitation site was determined noninvasively from the measured cardiac magnetic fields. The location was in the same anatomic region as found by intraoperative epicardial mapping. This result shows that magnetocardiography can be helpful for determining an accessory pathway also in patients with grossly abnormal cardiac anatomy.  相似文献   
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Abstract: Hamster stomach strips or isolated rat colons were superfused by the effluent from isolated hamster or rat lungs, respectively. Cigarette smoke ventilation of the lungs caused a decrease in the contractile responses of hamster stomach strips to prostaglandin E2 and of rat colons to angiotensin II, when Krebs buffer was used as perfusion medium. On rat colons, diluted blood was as effective carrier of the inhibitory compounds as was the buffer solution.  相似文献   
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90.
Contraceptive vaginal rings (CVR) releasing levonorgestrel and estradiol were used for contraceptive purposes in eight women. They were instructed to remove the CVR for five days only, in the case of bleeding. Three selected subjects were followed by plasma sampling during the first 60 days of treatment. Plasma concentrations of levonorgestrel, progesterone, estradiol and gonadotropins were determined. All subjects kept bleeding records and were controlled clinically in the course of treatment. The subjects were protected an average of 163 days by the CVR. Three subjects used the CVR 170--180 days without removing it and two subjects had to remove the CVR only once. Two subjects experienced quite regular bleedings, and metrorrhagic bleeding was present in one case. No pregnancies were observed during the follow-up period of 1304 days. Clinical examination revealed no pathological findings. The vaginal mucosa tolerated the treatment well. Out of those subjects who were followed by plasma sampling, pituitary suppression was more marked in the subject with continuous use of CVR.  相似文献   
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