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71.
72.
The investigated data shows that arsenic (As) in drinking water is associated with increased mortality from different types of cancers including liver cancer. In this study, blood and scalp hair samples of male liver cancer patients and healthy referents belonging to As exposed areas of Sindh Pakistan were analyzed for As contents. The As levels in drinking water of understudy area showed that sections of this population was exposed to 3-15-folds higher concentrations of As than permissible limit. For comparative purposes, blood and scalp hair samples of matched cancerous patient as referent patients belonging to big city (Hyderabad) who have used municipal treated water with low As levels <10?μg/L were also collected. The results of this study showed that the average As concentration was higher in the blood and scalp hair of exposed and non-exposed referent cancer patients as compared to referents (p?相似文献   
73.
The pathogenesis of some cardiovascular diseases (CVDs) has been altered with changes in the balance of certain trace and toxic elements. The aim of the present study was to assess the role of zinc (Zn) and cadmium (Cd) in smoker and nonsmoker male CVD patients (n = 457) of two age groups (31–45) and (46–60). The both elements were determined in biological samples (scalp hair, blood, and urine) of CVD patients and healthy referents for comparison purpose. The concentrations of Zn and Cd were measured by atomic absorption spectrophotometer prior to microwave-assisted acid digestion. It was observed that the mean values of Cd were significantly higher in the biological samples of smokers CVD as compared to nonsmoker CVD patients, while the level of Zn was lower in both smoker and nonsmoker patients. The concentrations of Zn in whole blood and scalp hair samples were lower in CVD patients as compared to referents (p > 0.001). Results showed significant changes of levels of Cd and Zn in blood and scalp hair samples of CVD patients when compared with healthy referents, while reverse in the case of urine samples. It was observed that low Zn levels were associated with both smoker and nonsmoker CVD patients, while increased cadmium accumulation was observed in smoker patients as compared to nonsmoker patients (p > 0.025).  相似文献   
74.
云南地方猪种随机群体与选育群的遗传差异(英文)   总被引:3,自引:0,他引:3  
Qu KX  Wu GS  Gou X  Yan DW  Lian LS  Baig M  Zhang YP 《动物学研究》2011,32(3):255-261
为估计随机群体与选育群间的遗传差异,测定了云南地方猪种102个个体438bp的线粒体DNA D-loop片段,涉及4个随机群体、1个保种群和1个核心群。检测的16个多态位点界定了20个单倍型,撒坝猪核心群和版纳微型猪保种群的单倍型数量仅为3个和1个,而4个随机群体的单倍型数量都在6个以上,4个随机群体的单倍型多态度极显著高于这两个选育群(h=0.732对0.425和0.000,exact test,P≤0.0036)。结果发现,选育会导致遗传多样性过低, 尽管在随机群体中有较高的遗传多样性,基于此,及早干预和合理的育种计划将会有效地阻止核心群和选育群的遗传多样性下降。否则,选育甚至会在短短几年内使遗传多样性程度急剧下降, 表明育种、保种与遗传多样性保存之间存在着尖锐冲突。该文还讨论了几个群体的遗传关系。  相似文献   
75.
N-methyl-D-aspartic acid receptor-dependent long term potentiation (LTP), a model of memory formation, requires Ca2+·calmodulin-dependent protein kinase II (αCaMKII) activity and Thr286 autophosphorylation via both global and local Ca2+ signaling, but the mechanisms of signal transduction are not understood. We tested the hypothesis that the Ca2+-binding activator protein calmodulin (CaM) is the primary decoder of Ca2+ signals, thereby determining the output, e.g. LTP. Thus, we investigated the function of CaM mutants, deficient in Ca2+ binding at sites 1 and 2 of the N-terminal lobe or sites 3 and 4 of the C-terminal CaM lobe, in the activation of αCaMKII. Occupancy of CaM Ca2+ binding sites 1, 3, and 4 is necessary and sufficient for full activation. Moreover, the N- and C-terminal CaM lobes have distinct functions. Ca2+ binding to N lobe Ca2+ binding site 1 increases the turnover rate of the enzyme 5-fold, whereas the C lobe plays a dual role; it is required for full activity, but in addition, via Ca2+ binding site 3, it stabilizes ATP binding to αCaMKII 4-fold. Thr286 autophosphorylation is also dependent on Ca2+ binding sites on both the N and the C lobes of CaM. As the CaM C lobe sites are populated by low amplitude/low frequency (global) Ca2+ signals, but occupancy of N lobe site 1 and thus activation of αCaMKII requires high amplitude/high frequency (local) Ca2+ signals, lobe-specific sensing of Ca2+-signaling patterns by CaM is proposed to explain the requirement for both global and local Ca2+ signaling in the induction of LTP via αCaMKII.  相似文献   
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77.
Foam cell formation is a hallmark event during atherosclerosis. The current paradigm is that lipid uptake by a scavenger receptor in macrophages initiates necrosis core formation that characterizes atherosclerosis. We report that NOS1-derived nitric oxide (NO) facilitates low-density lipoprotein (LDL) uptake by macrophages independent of the inflammatory response. LDL uptake could be dramatically suppressed by NOS1 specific inhibitor 1-(2-trifluoromethylphenyl) imidazole (TRIM). Importantly, the notion that NOS1 can mediate uptake of lipoproteins suggests that the foam cell formation is regulated by NOS1-derived NO-mediated mechanism. This is a novel study involving NOS1 as a critical player of foam cell formation and reveals much about the key molecular proteins involved in atherosclerosis. Targeting NOS1 would be a useful strategy in reducing LDL uptake by macrophages and hence dampening the atherosclerosis progression.  相似文献   
78.
Worldwide, food waste is one of the prime issues threatening food security and the Kingdom of Saudi Arabia (KSA) is not an exception. With 427 kg of food wasted per capita per year, the country ranks among the top food wasters. Ironically, the Kingdom has limited arable lands and scarce water resources to support mass-scale agriculture and to feed its increasing population, KSA relies heavily on imports and subsidized food to meet needs. Yet, food is wasted at restaurants, caterers, cafeterias and, especially, by households such that food waste is the single-largest component of the landfills. The review article is based on the grey and scientific literature published in the English and Arabic languages on the issue of food waste in Saudi Arabia. Information sources like Web of knowledge, online resources and the databases available through the King Saud University, Saudi Arabia were accessed and used to collect information on food waste, its social, cultural, economic and environmental impacts and related topics. Since food items and groceries are abundantly available to all living in KSA and they are highly subsidized, the residents take food for granted. According to a recent survey, about 78% of food purchased in KSA is discarded each week in order to make room for new groceries. The factors responsible for food waste include: lack of awareness; and insufficient and inappropriate planning when shopping. Food waste in restaurants, celebrations, social events and occasions are enormous. Waste is common in festivals and special events where the customs is to provide more food than required. There is a need to change society’s food culture, particularly among the women and the youth, as they are largest segment of the society and the prime food wasters. The analysis of the factors responsible for food waste, identified in this article suggests a “Stop Wasting Food” campaign should be launched. It is also recommended to determine and activate the role of extension education to reduce food waste in the KSA through vibrant capacity building programs for youth and women, in particular, and society in general.  相似文献   
79.
PurposeInappropriate application of pesticides is quite common in the study area, causing health issues and in some cases fatalities. The intent of the current study is to gauge the farmers’ level of knowledge on the safe usage of pesticides and biosafety to keep the famers healthy through the focused extension programs.MethodologyThe study is carried out in 41 union councils of Tehsil Sahiwal, District Sahiwal, Punjab, Pakistan. Data are collected through a cluster sampling technique by conducting face-to-face interviews. Statistical analysis is used to determine relationships and interpret them.ResultsThe findings show that the majority of farmers (87.2%) earn their livelihoods from farming and 2.1% are traders. More than half of the respondents (51.8%) own small land-holdings with an area of 4–8 ha, with only 16.4% having a land area of more than 12 ha. The results also reveal that the majority of respondents obtain information from private agents and only about one third (34.4%) respondents get information on the safe usage of pesticides from the Department of Agriculture (Extension). The internet has emerged as a fast and reliable source of information in the new paradigm; however, only 14.4% of the respondents take advantage of this economical and fast information tool/medium. The findings also reveal that the farmers employ unhealthy and poor practices by not following the recommendations regarding the safe usage of pesticides. The study also reveals that more than half of the farmers (54.4%) use unsafe storage practices on their farms, and about 48.2% do not follow the instructions.ConclusionsInappropriate application of pesticides can have negative effects on human health and the adoption safety measures are necessary to avoid the harmful effects of pesticides. Due to high illiteracy in the area, farmers mainly seek advice of neighboring farmers, having ignorance on the biosafety issues. Variables like education level, land ownership, total land size and the trainings on safe pesticide usage significantly influence the knowledge level of farmers on the safe usage of pesticides.RecommendationsFarmers do not follow the recommendations of the extension department or the instructions printed on pesticide bottles/containers, therefore educational (formal and informal) and training programs are necessary on the safe pesticide usage to upgrade their skills and expertise on safe usage of pesticides and the importance of biosafety.  相似文献   
80.
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