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181.
A registry of the rural population in the Altai region exposed to fallout from nuclear tests at the Semipalatinsk test site (STS) was established more than four decades after the first Soviet nuclear explosion on August 29, 1949. Information about individuals living in an exposed and a control area was collected using all available local sources, such as kolkhoz documentation, school registries, medical treatment records and interviews with residents. As a result, a database comprising an exposed group of 39 179 individuals from 53 Altai region villages, 6769 external and 3303 internal controls was compiled. For several settlements, effective dose estimates reached the level of 1.5 Sv, while the average effective dose estimate in the exposed group was 340 mSv. Dosimetric data, vital status information and health records gathered at rayon and village medical facilities are held in the registry. Cause-of-death information for deceased residents is obtained from death registration forms archived at the Altai region vital statistics office. At present, a follow-up of approximately 40% of the population exposed in 1949 has been done. More will be added by searching for migrants to the larger towns of the Altai region, i.e. Barnaul, Rubtsovsk and Biisk. In order to assess the influence of radiation exposure, analytical studies with a case-control design for stomach and lung cancer are currently being prepared. The number of known cases is sufficient to detect an odds ratio of 1.5 at the 95% confidence level. Epidemiological studies in populations affected by fallout from STS may be equally important to the atomic bomb survivors’ study for the direct quantification of radiation effects. The range of exposure rates experienced will extend the acute high-dose-rate findings from Hiroshima/Nagasaki towards acute and protracted lower exposures, which are more relevant for radiation protection issues. Received: 3 March 1999 / Accepted in revised form: 8 June 1999  相似文献   
182.
Symptoms of psychological distress and disorder have been widely reported in people under quarantine during the COVID-19 pandemic; in addition to severe disruption of peoples’ daily activity and sleep patterns. This study investigates the association between physical-activity levels and sleep patterns in quarantined individuals. An international Google online survey was launched in April 6th, 2020 for 12-weeks. Forty-one research organizations from Europe, North-Africa, Western-Asia, and the Americas promoted the survey through their networks to the general society, which was made available in 14 languages. The survey was presented in a differential format with questions related to responses “before” and “during” the confinement period. Participants responded to the Pittsburgh Sleep Quality Index (PSQI) questionnaire and the short form of the International Physical Activity Questionnaire. 5056 replies (59.4% female), from Europe (46.4%), Western-Asia (25.4%), America (14.8%) and North-Africa (13.3%) were analysed. The COVID-19 home confinement led to impaired sleep quality, as evidenced by the increase in the global PSQI score (4.37 ± 2.71 before home confinement vs. 5.32 ± 3.23 during home confinement) (p < 0.001). The frequency of individuals experiencing a good sleep decreased from 61% (n = 3063) before home confinement to 48% (n = 2405) during home confinement with highly active individuals experienced better sleep quality (p < 0.001) in both conditions. Time spent engaged in all physical-activity and the metabolic equivalent of task in each physical-activity category (i.e., vigorous, moderate, walking) decreased significantly during COVID-19 home confinement (p < 0.001). The number of hours of daily-sitting increased by ~2 hours/days during home confinement (p < 0.001). COVID-19 home confinement resulted in significantly negative alterations in sleep patterns and physical-activity levels. To maintain health during home confinement, physical-activity promotion and sleep hygiene education and support are strongly warranted.  相似文献   
183.
研究从生长、健康和营养价值方面评估了高水平的双低菜粕替代饲料鱼粉对大黄鱼潜在的危害。在鱼粉含量60%的基础饲料(FM)上按照质量分数用双低菜粕分别替代15%(CM15)、30%(CM30)、60%(CM60)和100%(CM100)的鱼粉,配制成5种实验饲料。每种饲料投喂5个网箱的大黄鱼[初重(135.38±1.02)g],即每个处理5个重复,进行12周的养殖实验。结果表明,当双低菜粕替代水平在15%和30%时,大黄鱼的生长及饲料系数并没有受到显著性的影响。然而,当替代水平高于30%时,大黄鱼的末重和特定生长率均显著降低,而饲料系数显著升高(P < 0.05)。当替代水平达到100%时,大黄鱼摄食率达到最高值而肥满度达到最低值(P < 0.05)。在组织形态方面,大黄鱼摄食双低菜粕替代的饲料后肠道绒毛的弯曲程度减少并且排列更加不规则,而肝细胞则呈现出圆形空泡状并伴随着细胞核的偏移。对大黄鱼骨骼进行X-射线扫描发现,摄食双低菜粕的大黄鱼椎体和头部出现了畸形。在营养价值方面,双低菜粕替代鱼粉并未显著影响大黄鱼背肌的脂肪含量、蛋白含量和氨基酸组成,然而脂肪酸组成受到了显著影响,即N-6系列脂肪酸含量显著升高,而DHA与EPA含量显著降低(P < 0.05)。根据欧洲食品安全局(EFSA)的相关标准,这些营养价值的变化并没有影响大黄鱼作为健康食品的功能。由此可见,高水平(60%和100%)的双低菜粕替代鱼粉对大黄鱼的负面影响主要表现为降低大黄鱼的生长性能、改变肠道和肝脏组织形态,以及影响大黄鱼的骨骼健康。然而,双低菜粕替代鱼粉养殖大黄鱼的肌肉仍然符合人类的膳食要求。因此,双低菜粕替代鱼粉并没有影响大黄鱼作为食用鱼的营养价值。  相似文献   
184.
李国锋 《人类学学报》2016,35(3):458-468
为了揭示中国东西部汉族小学生体质发育差异的动态变化,应用文献资料法和数理统计法,将中国学生体质与健康1985年和2010年两次调研中有关东部和西部汉族小学生体质数据进行统计和对比分析。结果表明:东部小学生体质持续优于西部小学生且总体上差异具有统计学意义(P<0.05),东西部小学生的身体形态、身体机能及城市小学生体育素质呈拉大的趋势,东西部乡村小学生的体育素质呈缩小的趋势;东西部小学生身体形态发育处于增长的长期趋势;东西部小学生肺活量全面下降具有统计学意义(P<0.05),西部小学生下降速度快于东部小学生;东西部小学生耐力跑全面下降而斜身引体全面提高且具有统计学意义(P<0.05);东西部小学生体育素质发展差异的特征比较明显,东部小学生体育素质项目提高数量、幅度和速度高于西部小学生而下降的数量、幅度和速度低于西部小学生。  相似文献   
185.
Orthoptera were monitored on field edge public footpaths on the east (leeward) and west (windward) side of hedgerows in Chelmsford, UK, in 2006. A total of 6 species were recorded from footpaths on the leeward side of hedgerows probably due to the shelter from the prevailing westerly winds provided by the trees and shrubs. On the windward side of hedgerows species richness and abundance of Orthoptera were reduced (only 4 species were recorded). It is suggested that shelter from the wind and the exposure to early morning sunlight for Orthoptera on the east side of hedgerows are important factors governing their occurrence on farmland. Many replicates had Environmental Stewardship (ES) scheme field margins adjacent but they did not affect Orthoptera species richness or abundance.  相似文献   
186.
The dependence of health and physical fitness on the socio-economic factors of rural families in southern Ethiopia is investigated, with particular emphasis on the role of inequality. This paper contributes to our knowledge of the effect of inequality on health in several ways: it compares the results of objective and subjective health measures, it distinguishes between wealth inequality and nutrition inequality, and it evaluates the impact of nutrition inequality both at the village level and at the household level. The subjective health measures are the number of days respondents were ill during the last month, their ability to walk distances, their ability to carry heavy loads, and their ability to work in the field. The objective health measure is having Body Mass Index (BMI) lower than 18.5. Males are healthier than females. Height has a positive and significant effect on health and fitness and the same is true for per-capita wealth measured at the village level. Availability of satisfactory health facilities has a negative effect on morbidity. Per-capita wealth inequality is positively associated with morbidity and with a low BMI. Within-household nutrition inequality has a complex effect on health and physical fitness: the effect is negative, but only for household members whose nutritional status is above the household mean. The results indicate a clear positive effect of economic well-being on health and physical fitness. The role of inequality is less clear, and certainly deserves further analyses at both the theoretical and empirical levels.  相似文献   
187.
Indigenous medicine is important to rural livelihoods, but lay knowledge and use of medicinal plants has not been extensively studied. Research in KwaZulu-Natal, South Africa, showed that medicinal plants were frequently used by villagers and contributed to their ability to cope with health problems. Knowledge of plants and household remedies was extensive and varied in that households often held different knowledge. Villagers mainly relied on common species, and were generally aware of alternative species for a certain ailment. People were flexible in their use of indigenous and western health care, which were both perceived as beneficial. Improved cooperation between health care systems could improve health standards. Extraction of medicinal plants has been described as unsustainable in the region—a situation not found in the study area. It is argued that conservation policies aimed to restrict access should be differential and potentially not include local consumption, since this may be ecologically unnecessary and entail local hardships.  相似文献   
188.
Knowledge of the plasma selenium levels associated with optimised concentration or activity of specific selenoproteins can provide considerable insights from epidemiological data on the possible involvement of those selenoproteins in health, most notably with respect to cancer. For cohort studies, if selenoproteins such as glutathione peroxidase and selenoprotein P are relevant to cancer, one might only expect to see an effect on risk when the concentrations in the cohort range from below, to above, the level needed to optimise the activity or concentration of these enzymes. Similarly, trials would only show a beneficial effect of supplementation if selenium status were raised from below, to above, the optimal concentration for the selenoproteins likely to be implicated in cancer risk, as occurred in the NPC trial but not in SELECT. The most powerful evidence for the involvement of selenoproteins in human health comes from epidemiological studies that have related single nucleotide polymorphisms in selenoproteins to disease risk. The totality of the evidence currently implicates GPx1, GPx4, SEPS1, Sep15, SEPP1 and TXNRD1 in conditions such as cardiovascular disease, pre-eclampsia and cancer. Future studies therefore need to determine not only selenium status, but genotype, both in selenoproteins and related pathways, when investigating the relationship of selenium with disease risk.  相似文献   
189.
In the United States, the racial and ethnic statistics published by the National Center for Health Statistics (NCHS) assume that each member of the U.S. population has a race and ethnicity and that if a member is black or white with respect to his risk of one disease, he is the same race with respect to his risk of another. Such an assumption is mistaken. Race and ethnicity are taken by the NCHS to be an intrinsic property of members of a population, when they should be taken to depend on interest. The actual or underlying race or ethnicity of members of a population depends on the risk whose variation within the population we wish to describe or explain.
Michael RootEmail:
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190.
In this paper, I examine the mastery of mothering skills and satisfaction with associated health services in women who had recently given birth in Montreal (n = 33). I compare experience between women of two distinct ethnocultural groups: Anglophone Euro-Canadian and Anglophone Afro-Caribbean. The overall aim is to discern differentials in the mastery of mothering skills and associated satisfaction with maternal and child health services. The study is framed by neo-Weberian social theory suggesting that modernization and bureaucratization increasingly eviscerate everyday skills and knowledge. These processes also lead to changes regarding what is considered credible ‘authoritative knowledge.’ I found that older Anglophone Euro-Canadians expressed the greatest skill deficits. They attempted to redress these deficits through consultation of professionally authored books, medical Web sites and health professionals. Older Anglophone Euro-Canadians saw these resources as sources of ‘authoritative knowledge.’ They also expressed dissatisfaction with related health services. In contrast, Anglophone Afro-Caribbeans and younger lower-income Anglophone Euro-Canadians expressed satisfaction with their skills. This derived from widespread previous experience with children and more extensive and readily available kith and kin networks. These were considered sources of ‘authoritative knowledge’ in this group. This group expressed less dissatisfaction with health services, as they did not need, or expect, these services to redress skill deficits.
Rob WhitleyEmail:
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