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Human cognitive ability shows consistent, positive associations with fitness components across the life-course. Underlying genetic variation should therefore be depleted by selection, which is not observed. Genetic variation in general cognitive ability (intelligence) could be maintained by a mutation–selection balance, with rare variants contributing to its genetic architecture. This study examines the association between the total number of rare stop-gain/loss, splice and missense exonic variants and cognitive ability in childhood and old age in the same individuals. Exome array data were obtained in the Lothian Birth Cohorts of 1921 and 1936 (combined N = 1596). General cognitive ability was assessed at age 11 years and in late life (79 and 70 years, respectively) and was modelled against the total number of stop-gain/loss, splice, and missense exonic variants, with minor allele frequency less than or equal to 0.01, using linear regression adjusted for age and sex. In both cohorts and in both the childhood and late-life models, there were no significant associations between rare variant burden in the exome and cognitive ability that survived correction for multiple testing. Contrary to our a priori hypothesis, we observed no evidence for an association between the total number of rare exonic variants and either childhood cognitive ability or late-life cognitive ability.  相似文献   
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We have standardized a method to assess the total effective xenoestrogen burden (TEXB) in human placentas by the extraction and separation by high-performance liquid chromatography of two fractions containing lipophilic xenoestrogens (alpha) and endogenous hormones (beta), followed by assessing their estrogenicity in MCF-7 breast cancer cell-based E-Screen and Yeast Estrogen Screen (YES) bioassays. The means of TEXB alpha concentrations (in estradiol equivalent (Eeq) units) were 1.32 and 0.77 Eeq pM g?1 placenta in the E-Screen and YES, respectively; TEXB beta concentrations were 6.97 and 11.56 Eeq pM g?1 placenta, respectively. The interclass correlation coefficient was low and a fair level of agreement was observed after kappa test correction. According to the E-Screen and YES, TEXB alpha was ≥LOD in 70.0 and 55.0% of the placentas and 92.5 and 82.5% in beta, respectively. Although both bioassays can be recommended for assessing TEXB, there is greater experience with the use of the E-Screen for estrogenic assessment after extensive extraction of complex human matrices.  相似文献   
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《Anthrozo?s》2013,26(4):519-533
ABSTRACT

Studies in human medicine show that care of chronically ill family members can affect the caregiver's life in several ways and cause “caregiver burden.” Companion animals are offered increasingly advanced veterinary treatments, sometimes involving home care. Owners choosing such treatments could thus face similar challenges when caring for their animals. This qualitative study uncovers impacts on an owner's life, when attending to the care of an aged or chronically ill dog and reflects on the differing roles of caregivers with animal and human patients. Twelve dog owners were selected for in-depth interviews based on the dogs' diagnoses, and the choice of treatments and care expected to affect the owner's life. Interviews were recorded, transcribed, and analyzed qualitatively. The dog owners reported several changes in their lives due to their dog's condition: practicalities like extra care, changes in use of the home, and restrictions relating to work, social life, and finances. These were time-consuming, tough, and annoying, but could often be dealt with through planning and prioritizing. Changes in the human–dog relationship and activities caused sadness and frustration, which in turn led to feelings of guilt, and in some cases created a feeling of loss. Also, concerns about the progress of the dog's condition, it's welfare, and euthanasia brought emotional distress and many doubts. The owners did, however, respond to the changes differently and as a result experienced different effects on their own life. This study confirms that the situations of caregivers with human and animal patients are in some ways similar, yet the study also identifies and reflects on some of the differences. These include the caregiver role and the options of assistance as well as euthanasia. Veterinary staff are urged to inform owners about possible impacts on their lives when considering careconsuming treatments, and to be aware of the need for support during treatment as well as in decisions about euthanasia.  相似文献   
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Percentage of forests saved due to establishment of protected areas is an important piece of information for government institutions and, therefore, is the goal of this study. However, non random location selection bias makes such information directly unobservable. To overcome this problem, propensity score matching was applied. Unlike in previous studies, impact of buffer zone management was assessed by estimating avoided deforestation in buffer zones and park edges. The study area is the state of Pará. Overall results revealed that park protection saved 0.72% of protected surface from deforestation during 2000–2004 year period (∼2900 km2 of forests). The highest percentage of avoided deforestation was recorded in protected areas, situated near deforestation hotspots: central part of Eastern Pará, alongside Trans-Amazonian highway and on the banks of Amazon River. The findings also suggest that buffer zones tend to reduce deforestation where pressure on forests is lower, but substitution effect takes over in areas of high deforestation pressure (since loggers are prevented from deforesting within conservation units, deforestation in surrounding areas increases). Finally, the study does not find evidence of edge effects in the state of Pará.  相似文献   
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BackgroundOropharynx is the anatomical site with the highest human papillomavirus (HPV) infection in head and neck. Many studies on HPV prevalence and p16INK4a positivity in oropharyngeal cancer have been published in recent years. We aimed to update the global burden estimates of oropharyngeal cancer attributable to HPV with the latest data and estimate global burden of tonsillar cancer and base of tongue cancer attributable to HPV by region and country.MethodsWe calculated the number of new cancer cases using the Cancer Incidence in Five Continents Volume XI (CI5XI) and country-specific population in 2012 issued by the United Nations. Estimates of HPV prevalence and p16INK4a positivity were obtained from literature search and pooled analyses where necessary.ResultsGlobally the number of oropharyngeal cancer and tonsillar cancer attributable to HPV were 42,000 and 20,000 in 2012, corresponding to AFs of 42.7% and 52.7%. The number of cancer cases attributable to HPV among males was about 4-fold greater than that among females. For both oropharyngeal cancer and tonsillar cancer, AFs were higher in more developed countries. Among HPV positive oropharyngeal cancer cases, 86.7%, 87.8%, and 92.5% could have been prevented by bivalent (2v), quadrivalent (4v), and nonavalent (9v) HPV vaccines.ConclusionsIt is worth considering the inclusion of HPV immunization in males, especially in the regions where oropharyngeal cancer is highly prevalent.  相似文献   
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In a methodological contribution, Dieffenbach & Stein (DS) (The Journal of Nutrition, 142(4), 771–773.) concluded that the double burden of malnutrition (DBM), represented by stunted child – overweight mother pairs (SCOM), is a statistical artifact, meaning that SCOM does not describe a unique phenomenon because the observed rates of SCOM across a number of countries were not strongly different from the product of observed rates of maternal overweight (OM) and child stunting (SC), which DS referred to as the expected rate of SCOM. However, a growing literature continues to use SCOM as an indicator of the DBM. This study shows that the analysis by DS is not sufficient to conclude that SCOM can be explained by the co-occurrence of OM and SC due to chance alone because the analysis by DS was conducted at the country level, but applied to SCOM, which is a household-level variable. Using Demographic and Health Surveys data from 202 country-year data sets, we do not confirm important implicit assumptions that are required for the claim by DS to be supported. We also outline that comparing the expected to the observed rate of SCOM is primarily informative when putting it in relation to factors that influence the supply and demand of food consumed by households. When considering these factors, we find further evidence that it is misleading to consider SCOM as a statistical artifact, as the difference between the observed and the expected rate of SCOM significantly differs by household wealth. Recognizing that SCOM is a distinct phenomenon is important for policymakers who develop double-duty strategies that address malnutrition, and for researchers who need useful indicators to study the determinants of malnutrition at the household level.  相似文献   
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目的:研究老年性白内障患者生活质量与自我效能感、自我感受负担和社会关系质量的相关性。方法:纳入我院于2018年8月~2020年12月期间接收的老年性白内障患者116例作为研究组,另选取同期来我院检查眼睛视力的100例志愿者作为对照组,两组均填写中文版低视力者生活质量量表(CLVQOL)、自我感受负担量表(SPBS)、一般自我效能感量表(GSES)、社会关系质量量表等评分量表。经Pearson线性相关分析CLVQOL评分与SPBS、GSES和社会关系质量的关系。结果:共发放问卷216份,收回有效问卷212份,回收率为98.15%。研究组的身体机能、精神心理、症状与视功能、社会活动、总分低于对照组,组间对比差异有统计学意义(P<0.05)。研究组身体因素、情感因素、经济因素、总分高于对照组(P<0.05)。研究组个体对环境挑战的认知、个体对自我的认知、个体对控制感的认知以及总分低于对照组(P<0.05)。研究组家庭承担、家庭亲密度、朋友关系、总分低于对照组(P<0.05)。Pearson线性相关分析结果显示,CLVQOL评分与GSES和社会关系质量呈正相关,而与SPBS呈负相关(P<0.05)。结论:老年性白内障患者生活质量较差,与自我效能感、自我感受负担和社会关系质量密切相关,应重视上述相关因素的改善,以提高患者生活质量。  相似文献   
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