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21.
Age at menarche in a Chuvashian rural population   总被引:1,自引:0,他引:1  
OBJECTIVES: The secular trend and familial influences on age at menarche among a rural Chuvashian population was examined in a cross-sectional community-based study. SUBJECTS AND METHODS: The cohort included 617 females aged 18-80 years, with age at menarche ranging from 10 to 24 years (mean 15.4 +/- 2.1). Statistical analyses included simple linear regression, maximum likelihood estimation and a whiskers plot. RESULTS: Women born during the second through the fourth decade of the 20th century showed increasing mean values of age at menarche from 15.4 (second decade) up to 16.5 (fourth decade). Women born after the fourth decade showed a decrease in mean values from 15.5 (fifth decade) to 13.0 (ninth decade). The highest peak of age at menarche was in women born in 1932. Significant familial correlations were observed between adjusted to year of birth age at menarche in mothers and daughters r = 0.195, p<0.01 and sisters and sisters r = 0.404, p<0.01. CONCLUSION: Our study demonstrated the certain secular trends of age at menarche in Chuvashian women who matured after World War II. Periods of socio-economic disasters such as war and famine disrupt the secular trend. Our findings also confirm the hypothesis of significant familial influences on menarcheal age.  相似文献   
22.
Height is a highly heritable and classic polygenic trait. Recent genome-wide association studies (GWAS) have revealed that at least 180 genetic variants influence adult height. However, these variants explain only about 10% of the phenotypic variation in height. Genetic analysis of short individuals can lead to the discovery of novel rare gene defects with a large effect on growth. In an effort to identify novel genes associated with short stature, genome-wide analysis for copy number variants (CNVs), using single-nucleotide polymorphism arrays, in 162 patients (149 families) with short stature was performed. Segregation analysis was performed if possible, and genes in CNVs were compared with information from GWAS, gene expression in rodents'' growth plates and published information. CNVs were detected in 40 families. In six families, a known cause of short stature was found (SHOX deletion or duplication, IGF1R deletion), in two combined with a de novo potentially pathogenic CNV. Thirty-three families had one or more potentially pathogenic CNVs (n=40). In 24 of these families, segregation analysis could be performed, identifying three de novo CNVs and nine CNVs segregating with short stature. Four were located near loci associated with height in GWAS (ADAMTS17, TULP4, PRKG2/BMP3 and PAPPA). Besides six CNVs known to be causative for short stature, 40 CNVs with possible pathogenicity were identified. Segregation studies and bioinformatics analysis suggested various potential candidate genes.  相似文献   
23.
Localization of vital components of neurological functioning has to be performed before epilepsy surgery can be considered in children with intractable epilepsy. This study reports the experience with the Wada procedure in very young children and/or developmentally delayed children with an a priori considerable chance of failing the procedure. The aim of this study was to indicate the applicability of this procedure in this patient group. The Wada procedure is described in 16 children under 10 years of age and/or have intelligence quotient scores below 50 and/or are critically ill and/or are behaviourally disturbed. Information on motor, language and memory functioning is obtained in respectively 13/15, 9/13, and 5/11 children. Nine children underwent epilepsy surgery without postoperative impairment of neurological functioning. In five children epilepsy surgery was not performed because of the results of the Wada procedure or the lack of information during the Wada procedure. One child became seizure-free before surgery. Even in very young, developmentally delayed or behaviourally disturbed children, the Wada test can provide important information with respect to the decision pro or contra epilepsy surgery.  相似文献   
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Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration.  相似文献   
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Comparisons of the seroepidemiology of genital herpes simplex virus (HSV) infection within and between countries are hampered by variations in tests, methods and populations sampled. Differences in seroprevalence may partly reflect variability in diagnostic efforts and healthcare awareness, expectations and utilization. To allow comparison between surveys and to improve their performance, seroepidemiological studies should use validated HSV type-specific tests, report age-specific or age-adjusted prevalence and define the period of time over which samples were collected. Despite the difficulty of comparing studies, the prevalence of HSV-2 infection varies between developed countries. Among healthy adult populations, HSV-2 seroprevalence is higher in the USA than in Europe. Furthermore, HSV-2 seroprevalence varies widely among European countries. For example, in 1989 HSV-2 seroprevalence among pregnant women was reported to be 33% in Sweden compared with 8.3% in Germany. In some, but not all, countries, HSV-2 seroprevalence appears to be increasing. In the USA, the National Health and Nutrition Examination Surveys found that HSV-2 seroprevalence increased by almost one third from 16.4% to 21.8% from 1976 to 1994 in people over 12 years old. The incidence of HSV infection is a measure of primary infection. HSV incidence is difficult to quantify, partly due to unrecognized or asymptomatic infections. However, estimates of incidence in North American and European populations range from 5 to 24 per 100 people per year. Prevention programmes should recognize that HSV-2 seroprevalence increases rapidly in early adult life. The proportion of genital herpes infections caused by HSV-1 is increasing in the developed world, possibly due to changes in oral-genital sexual behaviour and lower rates of HSV-1 acquisition in childhood.  相似文献   
29.
OBJECTIVES: In July 1997, the National Reference Center for Sexually Transmitted Diseases of Bangui, Central African Republic (CAR), was expanded by the creation of an anonymous and voluntary counseling and testing (VCT) unit for HIV infection, the Anonymous Surveillance Unit (Unité de Dépistage Anonyme [UDA]). The goal of the UDA was to initiate and promote voluntary HIV testing in the general adult population of Bangui. We carried out an observational and comprehensive survey over a 4-year period to document and analyze the experience of VCT in the UDA, with special attention to risk factors associated with HIV infection. METHODS: All clients for VCT were given adequate pretest counseling by trained counselors focused on knowledge about HIV infection and sexually transmitted infections, individual risks of acquiring HIV, and anticipation of the client's attitude about test results. After consent was obtained, a blood sample was drawn and tested for HIV by two ELISAs in parallel. The client paid a standard cost of $1.20 at the initial visit. After a week, test results were given to the client during the posttest visit, at which time HIV-seropositive individuals received emotional support and were referred to specific social or medical structures. Seronegative clients received reinforcement of prevention messages and were asked to come back for serologic follow-up free of charge after 3 (M3) and 12 (M12) months. RESULTS: From July 1997 to March 2001, 5686 individuals aged 14 to 65 years (mean age, 27 years) had an initial visit for VCT (V1). Peaks of UDA visitation (250-450 clients) were observed on the annual AIDS Day in the CAR, at which time HIV serologic testing was offered free of charge. A total of 5060 (89%) clients came back for a second visit (V2) to receive test results. Among those, 18.3% were infected with HIV type 1. Multivariate analysis of risk factors demonstrated marked association of HIV seropositivity with age, female gender, widowed/divorced women, poor or low education level, occupations such as civil servants or merchants, presence of symptoms of sexually transmitted infections, and lack of systematic condom use. Single young women were at higher risk for HIV infection compared with men of the same age (OR = 7.7 for women aged 15-24 years, 95% CI: 4.0-14.0; OR = 2.8 for women aged 25-34 years, 95% CI: 1.7-4.5). Widowed women older than 44 years of age were more likely to be HIV-seropositive than men (OR = 10.0; 95% CI: 1.7-83.6). A total of 885 (21%) HIV-seronegative individuals returned for follow-up at 3 months (M3; 0.45% rate of seroconversion). Seventy-nine (9%) individuals returned at 12 months (M12), without any new cases of HIV infection. HIV-negative clients consulting at M3 and M12 showed a significant reduction in unprotected intercourse with occasional sexual partners. CONCLUSION: This experience demonstrates that VCT for HIV infection is feasible in Central Africa.  相似文献   
30.
Using commercially available herpes simplex virus (HSV) type-specific serological diagnostic tests, HSV type 2 (HSV-2) antibody prevalence was assessed in two parallel prospective studies including 534 human immunodeficiency virus type 1 (HIV-1)-infected outpatients living in two areas of northern France. In the first cohort of 434 subjects, 223 (51%) individuals demonstrated a positive HSV-2 serological status while 66 (66%) of 100 subjects in the second cohort were seropositive for HSV-2 (51 versus 66%; P = 0.08). Among the 223 HSV-2-seropositive subjects identified in the first study cohort, only 22 (10%) had suffered from recurrent anogenital lesions during the past 12 months while 154 (69%) had no clinical history of herpesvirus infection. Our findings demonstrate high proportions of subclinical and undiagnosed HSV-2 infection in HIV-1-infected individuals and suggest that HSV type-specific serological testing in the French HIV-1-infected subpopulation could be an efficient strategy to diagnose clinically asymptomatic HSV-2 infections.  相似文献   
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