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11.
Metabolic Brain Disease - As feared and deadly human diseases globally, Rabies virus contrived mechanisms to escape early immune recognition via suppression of the interferon response. This study,...  相似文献   
12.

Background  

The number of potential life years lost due to accidents and injuries though poorly studied has resulted in tremendous economic and social loss to Nigeria. Numerous socio-cultural, economic and political factors including the current epidemic of ethnic and religious conflicts act in concert in predisposing to and enabling the ongoing catastrophe of accident and injuries in Nigeria.  相似文献   
13.
We assessed the association between prenatal smoking and respiratory distress syndrome (RDS) among triplets using a population-based retrospective cohort of 12,169 triplet live births in the United States between 1995 and 1997. Analysis was conducted using the generalised estimating equation framework to adjust for intra-cluster correlations. A total of 938 cases of RDS were reported comprising 35 among smoking (7.2%) and 903 among non-smoking gravidas (7.7%). The likelihood of RDS was comparable in both smoking categories [adjusted odds ratio (OR) = 0.93; 95% confidence interval (CI) = 0.65-1.32]. The risk for RDS due to smoking diminished with declining birth weight albeit non-significantly: low birth weight (OR = 0.99; 95% CI = 0.40-2.42), very low birth weight (OR = 0.85; 95% CI = 0.39-1.86), and extremely low birth weight (OR = 0.69; 95% CI = 0.30-1.58). In conclusion, among triplet neonates, smoking during pregnancy was not associated with respiratory distress syndrome.  相似文献   
14.
The purpose of this study is to investigate the association between maternal alcohol intake in pregnancy and the occurrence of early stillbirth using a retrospective cohort analysis of singleton births in Missouri that occurred in the period 1989 through 1997 (N=655,979). We used Cox proportional hazards regression to generate adjusted risk estimates for total, early, and late stillbirth associated with maternal alcohol intake and used the Robust Sandwich Estimator to adjust for intracluster correlations among sibships. Overall, a total of 3,508 counts of stillbirth were identified, yielding a stillbirth rate of 5.3 per 1,000. Among mothers who consumed alcohol during pregnancy, the stillbirth rate was 8.3 per 1,000. Mothers who consumed alcohol while pregnant were 40% more likely to experience stillbirth as compared with nondrinking mothers (adjusted hazards ratio=1.4, 95% confidence interval: 1.2-1.7). A dose-response relationship was evident; mothers who consumed five or more drinks per week during pregnancy experienced a 70% elevated risk of stillbirth compared with nondrinking mothers (adjusted hazards ratio=1.7; 95% confidence interval: 1.0-3.0). The risk of early stillbirth was 80% higher among drinking mothers compared with abstainers (adjusted hazards ratio=1.8; 95% confidence interval: 1.3-2.3). The elevated risks for both early and late stillbirth did not reach statistical significance when broken down by level of alcohol intake. In conclusion, maternal drinking during pregnancy is associated with an increased risk of early stillbirth. These findings underscore the need to reinforce current counseling strategies toward pregnant women and women who intend to conceive on the detrimental effects of alcohol use in pregnancy.  相似文献   
15.
OBJECTIVE: We investigated whether an association existed between single motherhood and neonatal mortality among twins and whether such a linkage varied by race. STUDY DESIGN: Retrospective cohort analysis on 446,570 twin live births (between 24-44 gestational weeks inclusive) in the United States from 1995 through 1998. Neonatal survival was compared between twins of single and those of married mothers for blacks and whites separately using Cox proportional hazards regression that adjusted for the confounding effects of education, parity, adequacy of prenatal care and maternal smoking during pregnancy. The Robust Sandwich Estimator was employed to adjust for intracluster correlation. RESULTS: The rates for neonatal mortality among blacks were 34.9 per 1,000 among married and 43.4 per 1,000 among single mothers. Among whites, the rates were 20.6 per 1,000 for married and 28.9 per 1,000 for unmarried mothers. Neonatal mortality was significantly elevated among white twins of single mothers (Hazard Ratio (HR) = 1.23; 95% Confidence Interval (CI) = 1.14-1.31) and among black twins of single mothers (HR = 1.12; 95% CI = 1.01-1.25). However, when gestational age was adjusted for, the association between single motherhood and neonatal mortality disappeared. CONCLUSION: Single motherhood was a risk factor for neonatal mortality among twins, and the disparity in survival was more accentuated among whites. The association between single motherhood and neonatal mortality was explained by the preponderance of preterm births among twins of unmarried gravidas. Our findings reinforce the importance of future research to develop and test interventions that will decrease the incidence of preterm birth.  相似文献   
16.
OBJECTIVE: The purpose of this study was to evaluate the association of parity with stillbirth and neonatal and infant death among triplets. STUDY DESIGN: This was a retrospective cohort study of 15,930 triplets who were delivered in the United States between 1995 and 1997. Infants of nulliparous mothers were compared with infants of multiparous mothers. Adjusted relative risks for death by parity were computed with the use of the generalized estimating equations framework. RESULTS: The likelihood for stillbirth (odds ratio, 3.40; 95% CI, 2.20-5.26) was significantly greater among nulliparous mothers. Neonatal (odds ratio, 1.17; 95% CI, 0.95-1.43) and infant mortality rates (odds ratio, 1.10; 95% CI, 0.92-1.32) were comparable, however. With an increase in parity, there was a consistent declining trend in the risk for stillbirth (P<.0001). CONCLUSION: Nulliparity more than triples the risk for intrauterine fetal death among triplets. This parity-related disparity underscores the need for care providers to be particularly concerned about triplet gestations among nulliparous mothers.  相似文献   
17.
OBJECTIVE: We investigated the relationship between low maternal age and neonatal survival among extremely preterm twins. METHODS: This was a retrospective cohort study on live births of extremely preterm twins delivered to teenaged mothers (aged 15-19 years) in the United States within the period 1995 through 1998. Overall neonatal and early and late neonatal mortality in this category was compared with that of a similar group of twins born to young adult mothers (aged 20-29 years). We used the generalized estimating equation framework in computing relative risks after adjusting for intracluster correlations. RESULTS: Analysis involved 2,290 extremely preterm liveborn twins of teenaged mothers and 8,709 born to young adult mothers. Overall, neonatal mortality was 29% higher among the extremely preterm twins born to teenaged mothers (adjusted odds ratio [OR] 1.29; 95% confidence interval [CI] 1.04%, 1.59%). The disparity in neonatal survival was chiefly in the early neonatal period (adjusted OR 1.34; 95% CI 1.07%, 1.67%), while late neonatal mortality was comparable (adjusted OR 0.91; 95% CI 0.58%, 1.42%). In addition, twins of teenaged mothers had significantly higher level of mortality, except for the birth weight category of 1,000-1,499 g. CONCLUSION: Low maternal age was found to be associated with elevated risk of neonatal death among extremely preterm twins. The preponderance of deaths among extremely preterm twins of teenaged mothers in the early neonatal period appeared to be responsible for the disparity in survival. This information may be useful for targeted interventions aimed at enhancing survival of extremely preterm twins born to teenagers, as well as for instituting optimal management options in the clinical setting. LEVEL OF EVIDENCE: II-2  相似文献   
18.
We sought to determine the impact of advanced paternal age on the birth outcomes of triplets in a retrospective cohort study on 15,156 triplets born in the United States from 1995 to 1997. The study group comprised fathers aged > or = 40 years. Two control groups consisting of mature (30 to 39 years) and younger (20 to 29 years) fathers were constructed for comparison of main end points. We applied the generalized estimating equation framework to obtain relative risk estimates after capturing the effect of sibling correlations within triplet clusters. Stillbirths were 35% and 26% higher among triplets of mature and older men, respectively, whereas neonatal mortality was 28% and 23% lower among infants of mature and older fathers, respectively, using younger fathers as the referent category. Although only the relative risk for neonatal mortality comparing triplets of mature and younger fathers was statistically significant, these results constitute high indices that represent an important burden of excess early mortality at the population level. Our findings demonstrate a "shifting phenomenon" whereby a higher level of intrauterine demise was compensated by a higher rate of extrauterine survival among triplets born to older fathers.  相似文献   
19.
We set out to estimate the association between smoking among pregnant women aged at least 40 years and pregnancy outcome by analyzing singleton live births in the United States between 1995 and 1997. The study group consisted of deliveries to mothers aged 40 years and older with two maternal age categories (20 to 29 and 30 to 39 years) as control. Although risks varied with maternal age, smoking was associated with a higher-than-expected risk for infant mortality in all maternal age categories. The highest rate of infant mortality associated with smoking after adjusting for confounding was among mothers aged 20 to 29 (hazard ratio [HR], 1.49; 95% confidence interval [CI], 1.28 to 1.75), while the lowest was among pregnant mothers in the 40 and above age category (HR, 1.03; 95% CI, 0.87 to 1.23). In utero fetal demise was highest among older smoking mothers (>/=40 years) and declined with decreasing age (p for trend <0.0001). In conclusion, the relationship between maternal smoking and pregnancy outcomes is modified by the age of the mother.  相似文献   
20.
The HIV epidemic is currently in its third decade without any sign of abating. Tuberculosis (TB) is responsible for a third of all AIDS deaths, 99% of which occur in developing countries. The two epidemics fuel each other, together making up the leading infectious causes of mortality worldwide. Tuberculosis-HIV coinfection presents special diagnostic and therapeutic challenges and constitutes an immense burden on the health care systems of heavily infected countries. Despite major gains that have been made in the past two decades, important questions still remain. To cope with the challenge of TB-HIV coinfection, further research in the design of diagnostic tests for tuberculosis, detection of drug resistant Mycobacterium tuberculosis strains in HIV-positive people, as well as development of more effective therapeutic agents and vaccines are urgently needed. It has become evident that this dual epidemic will persist unless comprehensive measures are instituted through the provision of sufficient funding in addition to expanding and strengthening current control strategies adopted by governments and international organizations.  相似文献   
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