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11.
E Franco L Villa T Rohan A Ferenczy M Petzl-Erler G Matlashewski 《Pan American journal of public health》1999,6(4):223-233
This article reports on a large longitudinal study, begun in 1993, of the natural history of human papillomavirus (HPV) infection and cervical neoplasia in a population of low-income women in S?o Paulo, Brazil, a city with one of the highest risks worldwide for cervical cancer. Known as the Ludwig-McGill cohort study, the epidemiological investigation focuses on persistent infection with oncogenic HPV types as the precursor event leading to cervical neoplasia. The objectives of this study are to: 1) study the epidemiology of persistent cervical HPV infection in asymptomatic women, 2) investigate whether persistent HPV infection increases risk of low-grade and high-grade cervical lesions, 3) search for determinants of persistent HPV infection, 4) search for molecular variants of HPV that may be associated with an increased risk of lesions, 5) investigate whether viral burden is correlated with persistent infections and with lesion risk, 6) study the antibody response to HPV as a predictor of persistence and lesion progression, and 7) examine the role of HLA typing and codon 72 p53 gene polymorphism in mediating HPV persistence and lesion severity. The study accrued 2,528 female subjects through March 1997. Subjects were followed up every 4 months in the first year, with twice-yearly return visits to take place in subsequent years. Participants undergo a questionnaire-based interview, have a cervical specimen taken for Pap cytology and HPV testing, and have a blood sample drawn for HPV antibody testing. A cervicography is performed once in the first year and every two years thereafter. In this article we describe the design and methods of the study, provide baseline cohort characteristics, and present a preliminary assessment of the prognostic value of baseline HPV status. 相似文献
12.
PURPOSE: Questionnaires provide a practical approach to measuring physical activity in children and adolescents, particularly for large-scale epidemiological studies. The purpose of the present study was to compare four habitual physical activity questionnaires and to assess their long-term reliabilities. METHODS: Subjects were female, aged 7-15 yr (and their parents), who participated in a cohort study in which predictors of the onset of menarche were being investigated. Questionnaires consisted of three single-item and one multi-item habitual physical activity questions and were sent to the 640 participants. Test-retest reliability of the questionnaires was assessed on 100 randomly selected participants 11 months later. RESULTS: The Spearman's correlation coefficient was highest (r = 0.40) between the Godin-Shephard Score and the Perspiration Score and was lowest (r = 0.10) between the Stairs Score and the Specific Activity Score. The correlation coefficients were higher when the questionnaires were reported to have been completed by the parents alone, rather than by parents with the assistance of their daughters. The test-retest reliabilities were r = 0.44 for the Perspiration Score, r = 0.59 for the Stairs Score, r = 0.48 for the Godin-Shephard Score, and r = 0.53 for the Specific Activity Score. The reliabilities were higher when the retest was reported to have been completed by the parents alone. CONCLUSIONS: This study suggests that the Perspiration Score, the Godin-Shephard Score, and the Specific Activity Score may provide simple and practical measures of habitual physical activity for children and adolescents. 相似文献
13.
Neck soft tissue and fat distribution: comparison between normal men and women by magnetic resonance imaging 总被引:9,自引:0,他引:9 下载免费PDF全文
BACKGROUND: Obesity and increased neck circumference are risk factors for the obstructive sleep apnoea/hypopnoea syndrome (SAHS). SAHS is more common in men than in women, despite the fact that women have higher rates of obesity and greater overall body fat. One factor in this apparently paradoxical sex distribution may be the differing patterns of fat deposition adjacent to the upper airway in men and women. A study was therefore undertaken to compare neck fat deposition in normal men and women. METHODS: Using T1 weighted magnetic resonance imaging, the fat and tissue volumes in the necks of 10 non-obese men and 10 women matched for age (men mean (SE) 36 (3) years, women 37 (3) years, p = 0.7), body mass index (both 25 (0. 6) kg/m2, p>0.9), and Epworth Sleepiness Score (both 5 (1), p = 0.9) were assessed; all denied symptoms of SAHS. RESULTS: Total neck soft tissue volume was greater in men (1295 (62) vs 928 (45) cm3, p<0. 001), but the volume of fat did not differ between the sexes (291 (29) vs 273 (18) cm3, p = 0.6). The only regions impinging on the pharynx which showed a larger absolute volume of fat in men (3.2 (0. 7) vs 1.1 (0.3) cm3, p = 0.01) and also a greater proportion of neck fat in men (1.3 (0.3)% vs 0.4 (0.1)%, p = 0.03) were the anterior segments inside the mandible at the palatal level. CONCLUSIONS: There are differences in neck fat deposition between the sexes which, together with the greater overall soft tissue loading on the airway in men, may be factors in the sex distribution of SAHS. 相似文献
14.
OBJECTIVE: Motor vehicle collisions are a leading cause of death and disability in pregnant women. The purpose of this study was to examine current restraint practices by pregnant women. Additionally, the beliefs and knowledge of pregnant women about restraint laws and effectiveness were studied. METHODS: From May of 1997 to January of 1998, women were surveyed at initial prenatal visit at four obstetrical clinics. Data collected included age, gravida, ethnicity, educational level attained, payor source, restraint use, and knowledge of effectiveness of restraint use. RESULTS: A total of 807 women completed surveys. Most always wore restraints before pregnancy, but increased restraint use during pregnancy (79% vs. 86%, chi2, p = 0.02). Only 52% used restraints properly. Significantly fewer women believed restraints were beneficial to mother and fetus in late pregnancy compared with early pregnancy. Only 21% of women were educated on proper restraint use during pregnancy. Comparison by payor mix showed no difference in use or education received. CONCLUSIONS: Most women use restraints and continue to do so during pregnancy, but they use them improperly. Pregnant women are familiar with mandatory restraint laws but are less informed about restraint use in pregnancy. Few women receive education from health care providers about proper restraint use. This study highlights the need for aggressive educational efforts to improve car restraint use in pregnant women, thereby reduce maternal and fetal injury and death. 相似文献
15.
Endoscopic dacryocystorhinostomy without silicone stenting 总被引:1,自引:0,他引:1
Mortimore S Banhegy GY Lancaster JL Karkanevatos A 《Journal of the Royal College of Surgeons of Edinburgh》1999,44(6):371-373
Fifteen endoscopic dacryocystorhinostomies (DCRs) were performed without the use of silicone stents. These patients were followed up for an average of eight months. This procedure was successful in 87% of cases as measured by patients' relief of symptoms and endoscopic visualisation of a middle meatal ostium draining the lacrimal sac. Endoscopic DCR without silicone stenting compares favourably with other techniques described in the literature which use silicone stents. It does not have the disadvantage of complications associated with these stents. 相似文献
16.
Dietary carotenoids and risk of lung cancer in a pooled analysis of seven cohort studies. 总被引:5,自引:0,他引:5
Satu M?nnist? Stephanie A Smith-Warner Donna Spiegelman Demetrius Albanes Kristin Anderson Piet A van den Brandt James R Cerhan Graham Colditz Diane Feskanich Jo L Freudenheim Edward Giovannucci R Alexandra Goldbohm Saxon Graham Anthony B Miller Thomas E Rohan Jarmo Virtamo Walter C Willett David J Hunter 《Cancer epidemiology, biomarkers & prevention》2004,13(1):40-48
Intervention trials with supplemental beta-carotene have observed either no effect or a harmful effect on lung cancer risk. Because food composition databases for specific carotenoids have only become available recently, epidemiological evidence relating usual dietary levels of these carotenoids with lung cancer risk is limited. We analyzed the association between lung cancer risk and intakes of specific carotenoids using the primary data from seven cohort studies in North America and Europe. Carotenoid intakes were estimated from dietary questionnaires administered at baseline in each study. We calculated study-specific multivariate relative risks (RRs) and combined these using a random-effects model. The multivariate models included smoking history and other potential risk factors. During follow-up of up to 7-16 years across studies, 3,155 incident lung cancer cases were diagnosed among 399,765 participants. beta-Carotene intake was not associated with lung cancer risk (pooled multivariate RR = 0.98; 95% confidence interval, 0.87-1.11; highest versus lowest quintile). The RRs for alpha-carotene, lutein/zeaxanthin, and lycopene were also close to unity. beta-Cryptoxanthin intake was inversely associated with lung cancer risk (RR = 0.76; 95% confidence interval, 0.67-0.86; highest versus lowest quintile). These results did not change after adjustment for intakes of vitamin C (with or without supplements), folate (with or without supplements), and other carotenoids and multivitamin use. The associations generally were similar among never, past, or current smokers and by histological type. Although smoking is the strongest risk factor for lung cancer, greater intake of foods high in beta-cryptoxanthin, such as citrus fruit, may modestly lower the risk. 相似文献
17.
Marie-Claude Rousseau Michal Abrahamowicz Luisa L Villa Maria Cecilia Costa Thomas E Rohan Eduardo L Franco 《Cancer epidemiology, biomarkers & prevention》2003,12(10):1029-1037
Women infected with multiple human papillomavirus (HPV) types seem to be at higher risk of cervical intraepithelial neoplasia, although there is controversy about whether coinfections are associated with lower or higher grades of dysplasia. There is no established risk factor profile for infection with multiple HPV types. We analyzed data from a prospective cohort of 2,075 Brazilian women to identify determinants of HPV coinfection. Cervical specimens were collected for cytology and HPV DNA detection. Data on baseline and time-dependent putative risk factors were obtained by interview. Baseline predictors of HPV coinfection included younger age, greater number of recent sexual partners, a history of condyloma but not of other sexually transmitted diseases, and younger age at first sexual intercourse. In repeated measures analyses, there was a weak positive association between the number of sexual partners in the time interval between two study visits and the risk of coinfection. Our results suggest that the risk factor profile for HPV coinfection among HPV-infected women shares several similarities with risk factors for any HPV infection. 相似文献
18.
Another Advanced Test of Theory of Mind: Evidence from Very High Functioning Adults with Autism or Asperger Syndrome 总被引:19,自引:0,他引:19
Simon Baron-Cohen Therese Jolliffe Catherine Mortimore Mary Robertson 《Journal of child psychology and psychiatry, and allied disciplines》1997,38(7):813-822
Previous studies have found a subgroup of people with autism or Asperger Syndrome who pass second-order tests of theory of mind. However, such tests have a ceiling in developmental terms corresponding to a mental age of about 6 years. It is therefore impossible to say if such individuals are intact or impaired in their theory of mind skills. We report the performance of very high functioning adults with autism or Asperger Syndrome on an adult test of theory of mind ability. The task involved inferring the mental state of a person just from the information in photographs of a person's eyes. Relative to age-matched normal controls and a clinical control group (adults with Tourette Syndrome), the group with autism and Asperger Syndrome were significantly impaired on this task. The autism and Asperger Syndrome sample was also impaired on Happe's strange stories tasks. In contrast, they were unimpaired on two control tasks: recognising gender from the eye region of the face, and recognising basic emotions from the whole face. This provides evidence for subtle mindreading deficits in very high functioning individuals on the autistic continuum. 相似文献
19.
Studies have shown family planning adoption is likely to be more effective for women when men are actively involved. The transtheoretical model of behavior change was used to examine men's involvement in general contraception and intrauterine device (IUD) use by their wives. The study was carried out in rural Vietnam with 651 eligible participants. Cons of IUD use for men in precontemplation and contemplation/preparation were significantly higher than those in the action/maintenance stages, whereas the reverse was true for pros of IUD. The self-efficacy for convincing wife to have IUD in precontemplation was significantly lower than for those in higher stages. Women's education and ages, spontaneous recall of modern contraceptive method, cons for IUD, and self-efficacy for contraception and for convincing wives to get IUD inserted (or continue use) were significant predictors of men's readiness to accept IUD. Interventions are targeted to reduce cons and increase self-efficacy for IUD use. 相似文献
20.
Gaurav Garg Pradeep Venkatesh Rohan Chawla Brijesh Takkar Shreyas Temkar Sourav Damodaran 《Indian journal of ophthalmology》2022,70(5):1657
Purpose:To determine and validate retinal vascular caliber measurements by using the confocal scanning laser ophthalmoscopy system. Retinal vasculature changes are often regarded as clinical markers for systemic disease.Methods:It was a prospective observational study conducted on 600 eyes of 300 normal subjects with no systemic or ocular illness from January 1, 2016 to June 30, 2017 in a tertiary referral eye center. Non-mydriatic infrared reflectance, blue reflectance, and blue peak blue autofluorescence fundus imaging were done on the confocal scanning laser ophthalmoscopy system. The dimensions of the retinal vessels were measured using inbuilt calipers at 1800 mm from the center of the optic disc. Internal and external dimensions were measured. Observer variation and its comparison using Image J software were assessed.Results:The median age was 29 years (18–50 years). Mean internal and external diameters for arterioles were 85.1 ± 12.4 mm and 105.0 ± 12.0 mm, and for venules were 133.8 ± 16.6 mm and 145.4 ± 16.1 mm, respectively. The mean internal and external wall thicknesses were 19.7 ± 8.0 mm and 11.0 ± 5.6 mm, and wall thickness-to-lumen ratios were 0.3 ± 0.1 and 0.1 ± 0.1, respectively. Arteriolar-to-venular ratio for lumen and vessel was 0.66 ± 0.1 and 0.74 ± 0.1, respectively. There was no statistically significant difference between age groups. Both inter- and intra-observer reproducibility was >95%. The Bland–Altman plot showed that the difference between measurements using both confocal scanning laser ophthalmoscopy and Image J software lies within the limits of agreement approximately 95% of the time.Conclusion:This is the first effort to develop a normative database by using a simple non-invasive confocal scanning laser ophthalmoscopy system with high observer reproducibility. 相似文献