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排序方式: 共有491条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2020,38(32):4940-4943
To determine the duration of immunity provided by the Hepatitis A vaccination (HepA), we evaluated a cohort of participants in Alaska 20 years after being immunized as infants. At recruitment, participants received two doses of inactivated HepA vaccine on one of three schedules. We conducted hepatitis A antibody (anti-HAV) testing for participants at the 20-year time-point. Seventy-five of the original 183 participants (41%) were available for follow-up. The overall anti-HAV geometric mean concentration was 29.9 mIU/mL (95% CI 22.4 mIU/mL, 39.7 mIU/mL) and 50 participants (68%) remained seropositive (titer ≥ 20 mIU/mL). Using a fractional polynomial model, the predicted percent seropositive at 25 years was 55.3%, 49.8% at 30 years and 45.7% at 35 years, suggesting that the percent sero-positive could drop below 50% earlier than previously expected. Further research is necessary to understand if protection continues after seropositivity diminishes or if a HepA booster dose may become necessary.  相似文献   
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The Journal of Behavioral Health Services & Research - Mental health (MH) disorders are associated with HIV-related risk and health outcomes. Primary care providers (PCPs) conducting MH...  相似文献   
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PurposeFarm youth continue to experience high rates of injury and deaths as a result of agricultural activities. Farm machinery, especially tractors, is the most common cause of casualties to youth. A Roll-Over Protection Structure (ROPS) along with a fastened seatbelt can prevent almost all injuries and fatalities from tractor overturns. Despite this knowledge, the use of seatbelts by farmers on ROPS tractors remains low. This study treats farm safety as a family issue and builds on the central role of parents as teachers and role models of farm safety for youth.MethodsThis research study used a longitudinal, repeated-measures, randomized-control design in which youth 10–19 years of age were randomly assigned to either of two intervention groups (parent-led group and staff-led group) or the control group.ResultsFathers in the parent-led group were less likely to operate ROPS tractors without a seatbelt compared with other groups. They were more likely to have communicated with youth about the importance of wearing seatbelts on ROPS tractors. Consequently, youth in the parent-led group were less likely to operate a ROPS tractor without a seatbelt than the control group at post-test.ConclusionsThis randomized control trial supports the effectiveness of a home-based, father-led farm safety intervention as a promising strategy for reducing youth as well as father-unsafe behaviors (related to tractor seatbelts) on the farm. This intervention appealed to fathers' strong motivation to practice tractor safety for the sake of their youth. Involving fathers helped change both father as well as youth unsafe tractor-seatbelt behaviors.  相似文献   
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《Vaccine》2016,34(30):3443-3446
We compared ≥4-fold increases in antibody titers by hemagglutination inhibition assay to RT-PCR results among 42 adults with PCR-confirmed influenza A virus illnesses. Serologic sensitivity was higher among unvaccinated (69%, 95% confidence interval [CI] = 48–90%) than vaccinated healthcare personnel (38%, 95% CI = 29–46%) in a 2010–11 prospective cohort.  相似文献   
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目的 分析河南省MSM人群HIV感染流行趋势,为河南省艾滋病防治政策与策略制定提供科学依据。方法 分析2008-2013年艾滋病病例报告系统中同性性传播HIV/AIDS病例的变化趋势,利用MSM人群艾滋病综合防治专项调查数据分析该人群HIV感染率及危险行为变化。结果 2008-2013年河南省同性性传播病例构成从1.3%上升到17.1%,呈现快速增长趋势;专项调查数据显示,MSM人群HIV感染率呈现快速上升趋势,从2008年的4.69%增至2013年的8.33%(趋势χ2=39.24,P<0.001).单因素分析结果显示,年龄(χ2=21.03,P<0.001)、文化程度(χ2=31.66,P<0.001)、职业(χ2=14.59,P=0.01)、最近1次肛交行为安全套使用情况(χ2=134.97,P<0.001)、最近6个月同性性行为安全套使用情况(χ2=97.15,P<0.001)、最近1年性病症状(χ2=67.21,P<0.001)以及梅毒感染(χ2=163.60,P<0.001)均为感染HIV的影响因素。多因素分析结果显示,年龄、性病症状史、感染梅毒与艾滋病防治知识不知晓为感染HIV的危险因素。结论 河南省MSM人群中HIV感染呈不断上升趋势,男男同性性传播已经成为主要感染途径,该人群不安全性行为普遍存在,亟需采取有效措施控制HIV在该人群中的传播。  相似文献   
8.
《Vaccine》2015,33(32):3887-3893
ObjectivesTo estimate the predictive value of self-reported hepatitis A vaccine (HepA) receipt for the presence of hepatitis A virus (HAV) antibody (anti-HAV) from either past infection or vaccination, as an indicator of HAV protection.MethodsUsing 2007–2012 National Health and Nutrition Examination Survey data, we assigned participants to 4 groups based on self-reported HepA receipt and anti-HAV results. We compared characteristics across groups and calculated three measures of agreement between self-report and serologic status (anti-HAV): percentage concordance, and positive (PPV) and negative (NPV) predictive values. Using logistic regression we investigated factors associated with agreement between self-reported vaccination status and serological results.ResultsDemographic and other characteristics varied significantly across the 4 groups. Overall agreement between self-reported HepA receipt and serological results was 63.6% (95% confidence interval [CI] 61.9–65.2); PPV and NPV of self-reported vaccination status for serological result were 47.0% (95% CI 44.2–49.8) and 69.4% (95% CI 67.0–71.8), respectively. Mexican American and foreign-born adults had the highest PPVs (71.5% [95% CI 65.9–76.5], and 75.8% [95% CI 71.4–79.7]) and the lowest NPVs (21.8% [95% CI 18.5–25.4], and 20.0% [95% CI 17.2–23.1]), respectively. Young (ages 20–29 years), US-born, and non-Hispanic White adults had the lowest PPVs (37.9% [95% CI 34.5–41.5], 39.1% [95% CI, 36.0–42.3], and 39.8% [36.1–43.7]), and the highest NPVs (76.9% [95% CI 72.2–81.0, 78.5% [95% CI 76.5–80.4)], and 80.6% [95% CI 78.2–82.8), respectively. Multivariate logistic analyses found age, race/ethnicity, education, place of birth and income to be significantly associated with agreement between self-reported vaccination status and serological results.ConclusionsWhen assessing hepatitis A protection, self-report of not having received HepA was most likely to identify persons at risk for hepatitis A infection (no anti-HAV) among young, US-born and non-Hispanic White adults, and self-report of HepA receipt was least likely to be reliable among adults with the same characteristics.  相似文献   
9.

Background and aim

The exact constellation of body composition characteristics among metabolically unhealthy obese (MUO) and nonobese (MUNO) children and adolescents remains unclear. The purpose of this study was to identify the major body composition determinants of metabolically unhealthy phenotypes among Chinese children and adolescents.

Methods and results

We used data from a cross-sectional survey in 2015 that included 1983 children and adolescents aged 6–18 years. Subjects were classified into two phenotypes based on a combination of body mass index (BMI) and metabolic syndrome components. Body composition was measured by dual-energy X-ray absorptiometry (DXA). Among all boys and among adolescent boys, those with MUNO phenotypes displayed significantly higher indices of body composition except for fat mass (FM) percentage and trunk-to-legs FM ratio compared with the metabolically healthy nonobese phenotype (all P < 0.05). MUO individuals had higher arm FM, lean body mass (LBM), and trunk lean mass compared to metabolically healthy obese individuals (all P < 0.05). Visceral fat mass (VFM) and BMI were the major independent determinants of MUNO (VFM, 6- to 9-year-old boys, OR = 1.02, 95% CI = 1.00–1.03, P = 0.021; BMI, 6- to 9-year-old girls, OR = 1.90, 95% CI = 1.31–2.84, P = 0.001; and adolescent boys, OR = 1.34, 95% CI = 1.23–1.44, P < 0.001). LBM was the major independent predictor of MUO among adolescent boys (OR = 1.90, 95% CI = 1.03–1.17, P = 0.003).

Conclusions

Among children and adolescents, the metabolically unhealthy phenotype was associated with excess of body composition, but with significant differences observed based on age and sex. VFM and LBM derived by DXA can predict the metabolically unhealthy phenotype effectively in specific sex and age groups.  相似文献   
10.
Infection with human immunodeficiency virus (HIV) disrupts the balance among γδ T cell subsets, with increasing Vδ1+ cells and substantial depletion of circulating Vδ2+ cells. Depletion is an indirect effect of HIV in CD4-negative Vδ2 cells, but is specific for phosphoantigen-responsive subpopulations identified by the Vγ2-Jγ1.2 (also called Vγ9-JγP) T cell receptor rearrangement. The extent of cell loss and recovery is related closely to clinical status, with highest levels of functional Vδ2 cells present in virus controllers (undetectable viremia in the absence of antiretroviral therapy). We review the mechanisms and clinical consequences for Vδ2 cell depletion in HIV disease. We address the question of whether HIV-mediated Vδ2 cell depletion, despite being an indirect effect of infection, is an important part of the immune evasion strategy for this virus. The important roles for Vδ2 cells, as effectors and immune regulators, identify key mechanisms affected by HIV and show the strong relationships between Vδ2 cell loss and immunodeficiency disease. This field is moving toward immune therapies based on targeting Vδ2 cells and we now have clear goals and expectations to guide interventional clinical trials.  相似文献   
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