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51.
RATIONALE: Although involuntary exposure to maternal smoking during the in utero period and to secondhand smoke are associated with occurrence of childhood asthma, few studies have investigated the role of active cigarette smoking on asthma onset during adolescence. OBJECTIVES: To determine whether regular smoking is associated with the new onset of asthma during adolescence. METHODS: We conducted a prospective cohort study among 2,609 children with no lifetime history of asthma or wheezing who were recruited from fourth- and seventh-grade classrooms and followed annually in schools in 12 southern California communities. Regular smoking was defined as smoking at least seven cigarettes per day on average over the week before and 300 cigarettes in the year before each annual interview. Incident asthma was defined using new cases of physician-diagnosed asthma. MEASUREMENTS AND MAIN RESULTS: Regular smoking was associated with increased risk of new-onset asthma. Children who reported smoking 300 or more cigarettes per year had a relative risk (RR) of 3.9 (95% confidence interval [95% CI], 1.7-8.5) for new-onset asthma compared with nonsmokers. The increased risk from regular smoking was greater in nonallergic than in allergic children. Regular smokers who were exposed to maternal smoking during gestation had the largest risk from active smoking (RR, 8.8; 95% CI, 3.2-24.0). CONCLUSIONS: Regular smoking increased risk for asthma among adolescents, especially for nonallergic adolescents and those exposed to maternal smoking during the in utero period.  相似文献   
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OBJECTIVE: The cardinal indication for surgical treatment of gallstones is pain attacks. However, following cholecystectomy, 20% of patients remain symptomatic. It is unclear to what extent post-cholecystectomy symptoms can be ascribed to persistence of preoperative symptoms or to new pathology. The pain and digestive pattern in gallstone patients has not been defined in a recent setting with ultrasonography as the diagnostic method. The aim of this study was to characterize a pain pattern that is typical for gallstone disease and to describe the extent of associated dyspepsia. MATERIAL AND METHODS: A total of 220 patients with symptomatic gallstone disease including complicated disease (acute cholecystitis and common bile duct stones) were interviewed using detailed questionnaires to disclose pain patterns and symptoms of indigestion. RESULTS: All patients had pain in the right upper quadrant (RUQ) including the upper midline epigastrium. The pain was localized to the right subcostal area in 20% and to the upper epigastrium in 14%, and in the rest (66%) it was more evenly distributed. An area of maximal pain could be defined in 90%. Maximal pain was located under the costal arch in 51% of patients and in the epigastrium in 41%, but in 3% behind the sternum and in 5% in the back. The pain was referred to the back in 63% of the patients. The mean visual analogue scale (VAS) score was very high: 90 mm on a 0-100 scale. A pattern of incipient or low-grade warning pain with a subsequent relatively steady state until subsiding in the same fashion was present in 90% of the patients. An urge to walk around was experienced by 71%. Pain attacks usually occurred in the late evening or at night (77%), with 85% of the attacks lasting for more than one hour and almost never less than half an hour. Sixty-six percent of the patients were intolerant to at least one kind of food, but only 48% to fatty foods. Symptoms of functional indigestion (gastroesophageal reflux, dyspepsia or irritable bowel symptoms) were seen in the vast majority in association with attacks. CONCLUSIONS: Gallstone-associated pain follows a certain pattern in the majority of patients. The pain is located in a defined area with a point of maximum intensity, is usually referred, and occurs mainly at night with duration of more than one hour. The majority of patients experience functional indigestion, mainly of the reflux type or dyspepsia.  相似文献   
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Background: Exposure to per- and polyfluoroalkyl substances (PFAS), a prevalent class of persistent pollutants, may increase the risk of type 2 diabetes.Objective: We examined associations between PFAS exposure and glucose metabolism in youth.Methods: Overweight/obese adolescents from the Study of Latino Adolescents at Risk of Type 2 Diabetes (SOLAR; n=310) participated in annual visits for an average of 3.3±2.9y. Generalizability of findings were tested in young adults from the Southern California Children’s Health Study (CHS; n=135) who participated in a clinical visit with a similar protocol. At each visit, oral glucose tolerance tests were performed to estimate glucose metabolism and β-cell function via the insulinogenic index. Four PFAS were measured at baseline using liquid chromatography–high-resolution mass spectrometry; high levels were defined as concentrations >66th percentile.Results: In females from the SOLAR, high perfluorohexane sulfonate (PFHxS) levels (2.0 ng/mL) were associated with the development of dysregulated glucose metabolism beginning in late puberty. The magnitude of these associations increased postpuberty and persisted through 18 years of age. For example, postpuberty, females with high PFHxS levels had 25-mg/dL higher 60-min glucose (95% CI: 12,39mg/dL; p<0.0001), 15-mg/dL higher 2-h glucose (95% CI: 1,28mg/dL; p=0.04), and 25% lower β-cell function (p=0.02) compared with females with low levels. Results were largely consistent in the CHS, where females with elevated PFHxS levels had 26-mg/dL higher 60-min glucose (95% CI: 6.0,46mg/dL; p=0.01) and 19-mg/dL higher 2-h glucose, which did not meet statistical significance (95% CI: 1,39mg/dL; p=0.08). In males, no consistent associations between PFHxS and glucose metabolism were observed. No consistent associations were observed for other PFAS and glucose metabolism.Discussion: Youth exposure to PFHxS was associated with dysregulated glucose metabolism in females, which may be due to changes in β-cell function. These associations appeared during puberty and were most pronounced postpuberty. https://doi.org/10.1289/EHP9200  相似文献   
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Prevalence and outcomes of sexual violence among high school students   总被引:2,自引:0,他引:2  
A cross sectional, school-based survey using self administered anonymous questionnaire was conducted in Addis Ababa and Western Shoa among high school students to determine the prevalence, and reported outcomes of sexual violence. A total of 1401 female students were involved in the study. The prevalence of completed rape and attempted rape among female students was 5% and 10% respectively. The age range of completed rape was between 12-23 years and 61/72 (85%) of the rape victims were under 18 years of age. No significant linear trend was observed among the different age intervals (Chi Square for linear trend = 1.18; p-value = 0.27). Of the total respondents 78%, believed that rape was a major problem. Sexual harassment was reported in 74% of female students. Among the seventy two girls who reported to be raped 17(24%) had vaginal discharge and 12(17%) became pregnant. Social isolation, fear and phobia, hopelessness and suicide attempt were reported in 33%, 19%, 22%, 6% of rape victims, respectively. It is concluded that the prevalence of sexual violence among high school students is a serious problem and concern. Awareness creation to adolescents and the family need to be introduced and schools should also devise appropriate sex education regarding damaging effect of rape and educate youth on sexuality and responsible sexual decision making.  相似文献   
59.
BACKGROUND: One of the countries where measles remains endemic is Ethiopia. Previously, sequence data from Measles Viruses (MV) circulating in Ethiopia were obtained from clinical specimens. Now the Ethiopian Health and Nutrition Research Institute (ENHRI) has implemented cell culture techniques to isolate measles virus and molecular epidemiologic studies can be generated more easily. OBJECTIVE: To characterize the strains of Measles Virus circulating in Ethiopia during measles outbreaks in 2006 using viral isolates, and compare the results to previously identified Ethiopian strains. METHODS: A case study and convenience sampling method were conducted on five measles outbreak cases tb identify the circulating measles virus genotype in Addis Ababa and Amhara regions of Ethiopia in 2006. RESULTS: Three isolates were obtained from five specimens collected in two regions (1 from Amhara: Bahir Dar, and 2 from Addis Ababa: Addis Ketema and Kolefe Keranio subcities) in Ethiopia during 2006. The viral isolates were analyzed using standard genotyping protocols and were classified as genotype B3, identical to the strain circulating widely in West Africa and imported into Europe (Britain, Netherlands, Germany) and America (Mexico, USA, Canada). CONCLUSION: The conserved sequences among three isolates, covering a 3-month period, suggest that this B3 strain was circulating in Addis Ababa, Bahir Dar and possibly elsewhere in Ethiopia. To interrupt the transmission and circulation of MV, Ethiopia needs a strong national program of epidemiological surveillance, with characterization of circulating MV performed in a timely manner.  相似文献   
60.
To investigate the effects of 12 monthly average air pollution levels on monthly prevalence of respiratory morbidity, the authors examined retrospective questionnaire data on 2034 4th-grade children from 12 Southern California communities that were enrolled in The Children's Health Study. Wheezing during the spring and summer months was associated with community levels of airborne particulate matter with a diameter < or = 10 microm (PM10) (odds ratio (OR) = 2.91; 95% confidence interval (CI) = 1.46-5.80), but was not associated with community levels of ozone, nitrogen dioxide, PM2.5 (diameter < or = 2.5), nitric acid, or formic acid. Logistic regression was performed on data stratified into two seasonal groups, spring/summer and fall/winter. Among asthmatics, the monthly prevalence of asthma medication use was associated with monthly levels of ozone, nitric acid, and acetic acid (OR = 1.80 [95%CI = 1.19-2.70]; OR = 1.80 [95%CI = 1.23-2.65]; OR = 1.57 [95% CI = 1.11-2.21]; respectively). Asthma medication use was more prevalent among children who spent more time outdoors--with consequential exposure to ozone--than among children who spent more time indoors (OR = 3.07 [95%CI = 1.61-5.86]; OR = 1.31 [95%CI = 0.47-2.71]; respectively). The authors concluded that monthly variations in some ambient air pollutants were associated with monthly respiratory morbidity among school children.  相似文献   
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