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101.

Considered in this paper is a broad range of evidence bearing on the calcium absorption hypothesis that has been advanced to explain high frequencies of the gene for persistence of lactase activity (PLA) among adults in northern Europe. According to that hypothesis, lactase‐sufficient individuals in early northern Europe enjoyed a selective advantage over lactase‐deficient ones that led to high incidences of PLA in adults of the region. Northern Europeans, the hypothesis goes, suffered from a dietary shortage of vitamin D and, in addition, were unable to synthesize adequate vitamin D from the sun's ultraviolet radiation because of northern Europe's cloudiness and its location in higher latitudes. This led to chronic vitamin D deficiency along with a reduced ability to absorb calcium from milk and lactose‐rich dairy products. As a result, the deficiency diseases rickets—which affects infants and children and can leave a child with bowlegs and other bone defects—and osteomalacia—which weakens and deforms the bones of adults—were common in early northern Europe, and represented powerful selective forces that contributed to development of the highly depigmented skin that is typical of the region's peoples. In addition, the hypothesis goes, calcium absorption was enhanced by a process independent of vitamin D. Such enhancement, found especially or solely among lactase‐sufficient individuals, was brought on by ingestion of lactose in milk and milk products. Thus, persons who enjoyed high lactase activity through life were favored in the struggle for survival, which ultimately led northern European peoples to have among the highest incidences of PLA in the world.

In this article, evidence, much of it recent, is presented to show that lactase‐deficient humans are able to absorb calcium from milk as readily, or nearly as readily, as lactase‐sufficient humans. Evidence is also presented that rickets and osteomalacia occur in parts of the world that have an abundance of sunshine, whether originating from customs that limit exposure to sunshine or otherwise; that heavy cloud cover and high latitude need not result in vitamin D deficiency, rickets, and osteomalacia; that, indeed, osteological evidence from archeological sites in northern Europe indicates that rickets and osteomalacia were quite rare in antiquity; that those conditions appear to have become common in northern Europe only with the advent of the Industrial Revolution, too short a time to have been a significant factor in bringing on the high incidences of PLA that prevail today; and that, indeed, the calcium absorption hypothesis is not confirmed by historical, osteoarcheological, or bio‐medical evidence.  相似文献   
102.
Abstract

Within an observational open study on the effects of a scheduled dosage of biscuits with iron, children with juvenile idiopathic arthritis were either supplemented with biscuits supplying iron fumarate (median 3.6?mg per day) or left to their customary dietary habits. After 4 months, supplemented children showed a more favourable percentage change of blood haemoglobin, while ferritin levels (markers of inflammation) remained stable. We conclude that the supply of iron with available dietary products may contribute to an adequate iron status in children with chronic inflammatory disorders in a stable situation.  相似文献   
103.
Abstract

To review health and safety practice s and to determine the occupational health status of dam workers in the Lesotho Highlands, a health and safety audit and a health study of 258 workers was undertaken. The workers were administered respiratory health questionnaires and underwent chest x-rays and lung function and audiometric testing. The audit revealed a low level of aware ness of health and safety issues at all levels of management and a lack of occupational medicine an d industrial hygiene systems. Noise-induced hearing loss occurred among 92% of the study subjects. Among the 158 dam construction workers, 5.4% had pneumoconiosis. With poorly developed laws and regulatory bodies, unsophisticated trade unions, and little client supervision, health and safety had a low priority in this construction project. Recommendations are made that are pertinent to health and safety management where international companies are operating in developing countries.  相似文献   
104.
《Global public health》2013,8(10):1170-1184
Abstract

Few studies have assessed if Sweden's injury prevention work has been equally effective for children of different socio-economic backgrounds. The goal of this paper is to review the country's injury rates for children over time, stratified by socio-economic status (SES), to see if the effects are similar across SES levels. This study employs a retrospective case-control study design, using data from the hospitalisation records of 51,225 children, which were linked to family socio-economic data. Children and adolescents in families receiving social welfare benefits, and those living with single parents and mothers with less education had higher risks of injuries leading to hospitalisation. The population-based safety work over the past decades seems to have had only minor effects on reducing the impact of socio-economic based difference in injury risks to younger Swedes.  相似文献   
105.
Contemporary research indicates promising anticonvulsant effect of curcumin. However, its poor oral bioavailability is a major hindrance toward its pharmacological action. Thus, this study was carried out to evaluate the acute effect of liposome‐entrapped curcumin on increasing current electroshock seizures (ICES) test, pentylenetetrazole (PTZ)‐induced seizures, and status epilepticus in mice. Liposome‐entrapped curcumin in doses 25 and 50 mg/kg demonstrated significant increase in seizure threshold current and latency to myoclonic and generalized seizures in ICES test and PTZ‐induced seizures, respectively. Similarly, liposomal‐entrapped curcumin also increased the latency to the onset and decreased the duration of seizures during status epilepticus in mice. To conclude, liposomal‐entrapped curcumin possesses anticonvulsant activity against status epilepticus in mice.  相似文献   
106.
107.
新疆褐牛是新疆自主培育而成的乳肉兼用品种,为新疆养牛业主打品种之一,深受广大农牧民喜爱,自育成以来为农牧民的增收致富做出了积极贡献。本文对新疆褐牛的种群现状、种群存在与发展的重要性与必要性进行了阐述,对种群发展所面临的一系列问题进行了深入分析,结合实际提出了发展对策。  相似文献   
108.
目的探讨不同层次护理人员对举证责任倒置制度(下称制度)的紧张状况是否存在差异.方法采用自编量表对1 826名护士进行问卷测试,比较不同年龄、工龄、职称、学历和不同等级医院护士对制度的紧张水平、紧张反应和应对能力.结果不同年龄、工龄、职称护士对制度的紧张水平和应对能力比较,差异有显著性意义(均P<0.01),高年资护士对制度的紧张水平和应变能力相对高于低年资护士;二级甲等医院护士对制度的紧张水平高于三级甲等医院.结论建议各医疗机构加强低年资护士的法律知识教育,提高其自我保护意识和应变能力,采取有效措施从容应对举证.  相似文献   
109.
Oliver CW  Burke C 《Injury》2004,35(10):1025-1030
The centenarian population is increasing yet there is little about their morbidity and mortality rates following hip fracture. The aim was to review centenarians treated for proximal femoral fractures in Edinburgh describing treatment outcomes in relation to mortality, walking ability and residential status comparing centenarians with a the more typical hip fracture population. In this retrospective review, 18 centenarians sustaining hip fractures in Edinburgh between 1998 and 2002 were compared to 18 randomly selected "normal" hip fracture patients aged 75-83 years. Centenarian in-hospital, 1 and 4 month mortality was 11.1, 33.3 and 50%, respectively, versus 0, 0 and 5.6% in the normal group. Centenarian 4 month mortality was significantly greater than that of the normal group (Fisher's Exact Test, P = 0.00723). A total of 22.2% of centenarians regained pre-fracture walking ability compared to 58.8% of the normal patients. A total 28.6% of centenarians could continue living independently post-fracture compared to 69.2% of the normal group.  相似文献   
110.
Chemotherapy‐induced peripheral neuropathy (CIPN) is a frequent adverse event. Nutritional status can become impaired in cancer patients, potentially contributing to neuropathy's evolution. Our aim was to evaluate serum micronutrients and prealbumin in a cohort of 113 solid‐cancer patients receiving platinum and taxane compounds during the development and recovery of neuropathy, up to 1 year after finishing treatment. CIPN was graded according to Total Neuropathy Score© and NCI.CTCv3 at T0 (baseline), T1 (1–3 months), and T12 (12 months) after chemotherapy. CIPN was classified as asymptomatic (< grade 2) or symptomatic (≥2). CIPN recovery was defined as ≥1 grade improvement at T12. Symptomatic CIPN developed in 52% of patients. Symptomatic patients presented a higher increase in TNSc (p < 0.001), in TNSr© (p < 0.001), and decrease in sural (p < 0.001) and radial nerve conduction (p < 0.001). No significant differences with any of the micronutrients were observed along T0‐T1 period between severity or chemotherapy groups. By T12, symptomatic patients without recovery had a decrease in vitamin E levels (p = 0.019) and prealbumin (p = 0.062) compared with those symptomatic that improved. A correlation between the variation of vitamin E and prealbumin at T0‐T1 (r = 0.626, p = 0.001) and T1‐T12 (r = 0.411, p = 0.06) was observed. After chemotherapy treatment, the improvement of patients displaying symptomatic neuropathy is related to vitamin E and prealbumin serum levels. Our results suggest that nutritional status can play a role in CIPN recovery.  相似文献   
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