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排序方式: 共有526条查询结果,搜索用时 15 毫秒
1.
Robert Willer Farinazzo Vitral Carlos de Souza Telles Marcelo Reis Fraga Roberto Sotto Maior Fortes de Oliveira Orlando Motohiro Tanaka 《American journal of orthodontics and dentofacial orthopedics》2004,126(1):48-52
Thirty persons with Class II Division 1 subdivision malocclusions, ranging in age from 12 years 8 months to 42 years, underwent computed tomography of the temporomandibular joints. The images obtained from sagittal slices were used to assess the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, the condyle-fossa relationship, and the concentric position of the condyles associated with this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations (r) were determined after measurements on both Class I and Class II sides were obtained. No statistically significant asymmetries were found in the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, or the condyle-fossa relationship. However, a statistically significant (P <.05) anterior positioning of the condyles was observed. 相似文献
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Fredrik Nyberg Antonio Agudo Paolo Boffetta Cristina Fortes Carlos A. Gonzalez Göran Pershagen 《Cancer causes & control : CCC》1998,9(2):173-182
Objectives: The purpose of this study was to validate, in a case-control study, the reporting by lung cancer cases and controls of their own lifetime smoking habits and of the smoking habit of the spouse. Methods: In a multicenter (Sweden, Spain, Italy) case-control study of environmental tobacco smoke (ETS) and lung cancer, subjects were screened by repeated probing to exclude regular smokers of one cigarette/day or more for one year or more, and to quantify any occasional smoking. We then performed a short validation interview with next-of-kin in three centers. Results: Only five of 408 index subjects who had never smoked regularly (1.7 percent) were reported by next-of-kin to be former regular smokers. These subjects had a cumulative lifetime consumption of cigarettes below 1.1 pack years. Among 351 subjects with quantitative smoking information from both sources who reported ever smoking 400 cigarettes or less (the definition of never-smoker used in the multicenter ETS study), nine subjects (2.6 percent) had smoked more than this amount occasionally according to next-of-kin. Misclassification was not higher for cases than controls. Relative risks for lung cancer associated with indicators of ETS exposure were not substantially altered by excluding the nine possibly misclassified subjects. The reports from 223 pairs of index subjects and next-of kin regarding the cumulative amount smoked by the spouse agreed quite well (Spearman's rank correlation 0.75 for reported smokers, 0.92 for all subjects). Only one index subject failed to report a spouse who had smoked regularly (99 percent sensitivity). Conclusions: Smoking status and exposure to spousal ETS as reported by lung cancer cases and controls agreed strongly with reports by next-of-kin. Overall, our results suggest that bias from smoker misclassification is likely to be insignificant, and they contribute to the evidence linking exposure to ETS with an increased risk of lung cancer. 相似文献
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Carolina Gasparinho Maria Helena Gonalves Assucênio Chissaque Giovani L. Silva Filomeno Fortes Luzia Gonalves 《Nutrients》2022,14(11)
Undernutrition, anemia, and intestinal parasitic infections are public health problems in Angola, especially in pre-school children. We analyzed binary data from a longitudinal four-arm randomized parallel trial conducted in Bengo Province, northern Angola, over the course of two years, with seven follow-up assessments to explore the effects of four interventions (deworming and a test-and-treat approach for intestinal parasites, at both the individual and household levels) on wasting and stunting, and to understand their indirect benefits for anemia, malaria, diarrhea, and vomiting. A total of 121 children with intestinal parasitic infections received baseline treatment, and were allocated to the four arms (1:1:1:1). Using continuous outcome variables of height-for-age (HAZ) and weight-for-height (WHZ) statistical approaches did not reveal a clear benefit of any particular arm (Pathogens 2021, 10, 309). Next, HAZ and WHZ were transformed into binary variables of stunting and wasting, respectively, considering their mild-to-severe (Z-score < −1) and moderate-to-severe degrees (Z-score < −2). Original clinical data (on anemia, diarrhea, vomiting, and malaria) were also analyzed. From a binary longitudinal analysis with different dependence structures, using the R package bild, fitted models revealed the potential benefit of a test-and-treat approach at the individual level for wasting compared with annual albendazole at the individual level, especially considering mild-to-severe forms (ORadj = 0.27; p = 0.007). All arms showed similar effects on stunting, compared with annual albendazole, at a 5% significance level. Time and age at baseline presented favorable effects in the percentage of stunting using both severity degrees. Results showed a decreased chance of having anemia and diarrhea over time, although with no significant differences between arms. Data from longitudinal studies are essential to study the direct and indirect effects of interventions, such as deworming, and to explore additional approaches aiming at better understanding the temporal structure of nutrition and health outcomes in children. 相似文献
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Adri Ramírez Mena Ndeye Fatou Ngom Judicaël Tine Kine Ndiaye Louise Fortes Ousseynou Ndiaye Maguette Fall Assietou Gaye Daye Ka Moussa Seydi Gilles Wandeler 《Viruses》2022,14(8)
Hepatitis B virus (HBV) infection is the first cause of liver cirrhosis and cancer in West Africa. Although the exposure to additional environmental and infectious risk factors may lead to the faster progression of liver disease, few large-scale studies have evaluated the determinants of HBV-related liver fibrosis in the region. We used transient elastography to evaluate the prevalence of liver fibrosis and assessed the association between HBV markers and significant liver fibrosis in a cohort of people living with HBV in Dakar, Senegal. The prevalence of significant liver fibrosis was 12.5% (95% confidence interval [CI] 9.6%–15.9%) among 471 people with HBV mono-infection (pwHBV) and 6.4% (95% CI 2.6%–12.7%) in 110 people with HIV/HBV co-infection (pwHIV/HBV) on tenofovir-containing antiretroviral therapy (p = 0.07). An HBV viral load > 2000 IU/mL was found in 133 (28.3%) pwHBV and 5 (4.7%) pwHIV/HBV, and was associated with significant liver fibrosis (adjusted odds ratio (aOR) 1.95, 95% CI 1.04–3.66). Male participants (aOR 4.32, 95% CI 2.01–8.96) and those with elevated ALT (aOR 4.32, 95% CI 2.01–8.96) were especially at risk of having significant liver fibrosis. Our study shows that people with an HBV viral load above 2000 IU/mL have a two-fold increase in the risk of liver fibrosis and may have to be considered for antiviral therapy, independent of other disease parameters. 相似文献
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Franco Mdo C Akamine EH Di Marco GS Casarini DE Fortes ZB Tostes RC Carvalho MH Nigro D 《Cardiovascular research》2003,59(3):767-775
OBJECTIVE: We previously reported that intrauterine undernutrition increased the oxidative stress by decreasing superoxide dismutase activity. In the present study, we tested whether NADPH oxidase, xanthine oxidase, cyclooxygenase or nitric oxide synthase are responsible for the increased O(2)(-) generation observed in rats submitted to intrauterine undernutrition. In addition, we investigated the effect of angiotensin II (ANG II) on O(2)(-) production via activation of NADPH oxidase. METHODS: Female pregnant Wistar rats were fed either normal or 50% of the normal intake diets, during the whole gestational period. At 16 weeks of age, the rats were used for the study of intravital fluorescence microscopy; microvascular reactivity, local ANG II concentration and AT(1), p22(phox) and gp91(phox) gene expression. In this study only the male offspring was used. RESULTS: Treatment of mesenteric arterioles with the xanthine oxidase inhibitor oxypurinol, the nitric oxide synthase inhibitor L-NAME or the cyclooxygenase inhibitor diclofenac did not significantly change superoxide production. Thus, these vascular sources of superoxide were not responsible for the increased superoxide concentration. In contrast, treatment with the NADPH oxidase inhibitor apocynin significantly decreased superoxide generation and improved vascular function. On the other hand, intrauterine undernutrition did not alter the gene expression for p22(phox) and gp91(phox). The fact that the local ANG II concentration was increased and the attenuation of oxidative stress by blocking AT(1) receptor with losartan, led us to suggest that ANG II induces O(2)(-) generation in intrauterine undernourished rats. CONCLUSION: Our study shows that NADPH oxidase inhibition attenuated superoxide anion generation and ameliorated vascular function in rats submitted to intrauterine undernutrition. Although it is not clear which mechanisms are responsible for the increase in NADPH oxidase activity, a role for ANG II-mediated superoxide production via activation of NADPH oxidase is suggested. 相似文献
9.
乐胃煎逆转胃癌前病变AgNOR及细胞图像分析 总被引:3,自引:0,他引:3
目的研究乐胃煎逆转胃癌前病变不完全结肠型肠化和/或中度异型增生的疗效.方法胃镜病理证实为不完全结肠型肠化和/或中度异型增生46例.治疗组30例用乐胃煎,对照组16例用德诺(De_Nol).治疗前后胃镜活检胃窦固定部位粘膜标本作AgNOR染色及细胞图像分析.结果乐胃煎对不完全结肠型肠化及中度异型增生总有效率均高于De_Nol,分别为72%比25%(P<005)和895%比444%(P<005).乐胃煎治疗前后,AgNOR计数分别为730±116和481±150(P<001),De_Nol组为773±092和705±102(P<001).两组治疗前后AgNOR计数差值均数相比,统计学上也有显著性差异,分别为252±154和069±048(P<001).乐胃煎组中20例作细胞图像分析,治疗后各参数(长轴、短轴、核浆比、结构异型指数等)均有不同程度的降低,有显著性差异.结论乐胃煎确有较好地逆转胃癌前病变的功效. 相似文献
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