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71.
近年来,越来越多的人因为对更高的物质生活追求而承受着巨大的工作压力,从而忽视了健康.大多数人都处于亚健康的状态.从日常生活出发,分析了健康对人类的重要性,以期有助于处于亚健康的人群.  相似文献   
72.
近年来,越来越多的人因为对更高的物质生活追求而承受着巨大的工作压力,从而忽视了健康。大多数人都处于亚健康的状态。从日常生活出发,分析了健康对人类的重要性,以期有助于处于亚健康的人群。  相似文献   
73.
影响池养鳜健康的关键水生态因子   总被引:1,自引:0,他引:1  
赖子尼 《水产学报》2008,32(4):601-607
池塘生态系统是一个动态、多因素、非典型的复杂系统,用单因素统计法难以研究池塘养殖中的生态问题.在16口鳜养殖塘进行试验(总面积为4.7 hm2),每两周采样一次,获取鳜健康指标和pH、铵氮、硝酸盐氮、二氧化碳、总碱度、镁和细菌总数等17项水生态因子的87组监测数据,并对数据进行数理统计,研究探讨用权重因子、偏回归平方和、F检验值和相关系数等统计量优化进入鳜健康模型的因子.在满足一定准确度条件下,优选出用pH、铵氮、硝酸盐氮、二氧化碳、总碱度、镁浓度和细菌总数等7项因子为自变量,利用回归技术,求出它们与鳜健康指标(y)的关系模型为的非线性模型,模型的预报准确率为92.4%.借助所得模型进一步推导出对鳜健康指标影响由大到小的因子是细菌总数、二氧化碳、pH、铵氮,他们的最佳取值范围依次为(13~27)×104 cfu·L-1、小于3 mL·L-1、7.5~8.0、0.5 mL·L-1.  相似文献   
74.
Miang茶是泰国北部地区居民一类传统日常食用的腌茶,是一种将茶树鲜叶通过腌制发酵的方法制得的食品.文章回顾了该茶的历史,论述了该茶的采摘与加工工艺,简述了亚洲相关国家如中国、日本、老挝、缅甸等地的腌茶,论述了Miang茶在泰国北部悠久的历史和重要的经济价值.探讨了这种天然的发酵类茶的化学成分和微生物种类及相关菌群对人体健康的益处.最后论述了该茶所面临的挑战,以期为Miang茶的进一步深入研究提供指导.  相似文献   
75.
In high-income countries depression and cardiovascular diseases were predicted to be the two leading causes of DALYs in the year 2030. Private-life stress fosters both kinds of diseases. Scientific findings already show that forest exposure has stress-reducing effects. Particularly in Japan, people have practiced forest bathing to improve their health. The German population also has a strong connection to its forests, and forest law allows forest access, regardless of ownership structure. Hence, the question arises of whether forest exposure could be used in Germany as a kind of stress-coping strategy. To a certain degree, the success of such a strategy in Germany would require the participation of the stakeholders that are active in both the health and the forestry sectors. Therefore, it seems necessary to gain insight into German forest and health professionals' understanding and attitude concerning forest-related health benefits. For this reason, in this pilot study, guideline interviews with professionals of both sectors and with professionals standing in between these professions were conducted, recorded and transcribed. On the one hand, each professional’s presumptions regarding the health-fostering effects of forests were investigated, derived from their subjective certainty that forest exposure has health-fostering effects. In addition, a thought experiment was used to estimate the level of willingness to cooperate with each other in order to motivate people to be physically active in forests. For analysis, Mayring’s qualitative content analysis and a frequency analysis (MaxQDA) were applied. Findings show that most of the interviewed professionals presume forests to have health-fostering effects. Furthermore, something derived from the statements within the context of the thought experiment was that most professionals seem to be willing to cooperate with the other sector. Hence, it might be conceivable that forest exposure may be part of a German stress-coping strategy.  相似文献   
76.
AIM: To investigate whether metformin enhances the sensitivity of human breast cancer MDA-MB-231 cells to tamoxifen by down-regulating c-Myc. METHODS: The cell viability, colony formation, apoptosis, and migration and invasion abilities of MDA-MB-231 cells were detected by CCK-8 assay, colony formation experiment, flow cytometry and Transwell assay. The expression level of c-Myc was quantified by Western blot and immunohistochemical analysis. The antitumor effects of metformin and tamoxifen were investigated in vivo in a MDA-MB-231 triple-negative breast cancer xenograft model in the SCID mice. RESULTS: Metformin in combination with tamoxifen exerted synergistic effects on inhibition of the viability, colony formation, migration and invasion, and induced the apoptosis compared with the controls and either agent treatment alone in the MDA-MB-231 cells. The levels of c-Myc was down-regulated in vitro by treatment with metformin and/or tamoxifen (P<0.01). Moreover, metformin or in combination with tamoxifen also reduced the growth of MDA-MB-231 breast cancer tumors in the SCID mice by down-regulation of c-Myc in vivo. CONCLUSION: Metformin in combination with tamoxifen exerts synergistic effects on inhibition of the proliferation, migration, invasion and tumor growth of human triple-negative breast cancer MDA-MB-231 cells by down-regulating c-Myc expression, suggesting that metformin in combination with tamoxifen merits further evaluation as a target.  相似文献   
77.
《兽医公共卫生学》是动物医学专业的核心课程之一。为了提高教学质量,提升学生的学习兴趣,适应新型兽医人才培养要求。以《兽医公共卫生学》课程为例,对云南农业大学2届学生进行案例教学的实践与探索。结果表明,案例教学能显著地提高期末卷面成绩,学生对案例教学满意度较高,案例式教学能激发学生学习兴趣、增强学生现场认知感,提高学生综合能力,有利于提升《兽医公共卫生学》教学效果,为课程案例库建设提供依据。  相似文献   
78.
为探究学校供餐计划对人力资本积累的影响,采用文献综述方法,系统回顾和梳理学校供餐计划的国际研究进展,阐明学校供餐计划的概念和理论基础,重点分析其对人力资本积累的短期影响、长期效果以及溢出效应。在此基础上,探究学校供餐计划的方案设计和国际经验,进一步分析现阶段中国农村义务教育学生营养改善计划取得的成效和可能的不足,并提出相应完善建议。结果表明:学校供餐计划对人力资本积累具有重要影响,中国需要进一步构建项目监督和激励机制,结合其他益贫政策,发挥营养健康教育的协同作用,进而提高人力资本和促进乡村振兴。本研究的梳理总结有助于加深对学校供餐计划的认识,同时为我国有效实施营养干预项目,促进儿童人力资本积累和减少贫困代际转移提供借鉴和思考。  相似文献   
79.
Yield levels in smallholder farming systems in semi-arid sub-Saharan Africa are generally low. Water shortage in the root zone during critical crop development stages is a fundamental constraining factor. While there is ample evidence to show that conservation tillage can promote soil health, it has recently been suggested that the main benefit in semi-arid farming systems may in fact be an in situ water harvesting effect. In this paper we present the result from an on-farm conservation tillage experiment (combining ripping with mulch and manure application) that was carried out in North Eastern Tanzania from 2005 to 2008. Special attention was given to the effects of the tested treatment on the capacity of the soil to retain moisture. The tested conservation treatment only had a clear yield increasing effect during one of the six experimental seasons (maize grain yields increased by 41%, and biomass by 65%), and this was a season that received exceptional amounts of rainfall (549 mm). While the other seasons provided mixed results, there seemed to be an increasing yield gap between the conservation tillage treatment and the control towards the end of the experiment, and cumulatively the yield increased with 17%. Regarding soil system changes, small but significant effects on chemical and microbiological properties, but not on physical properties, were observed. This raises questions about the suggested water harvesting effect and its potential to contribute to stabilized yield levels under semi-arid conditions. We conclude that, at least in a shorter time perspective, the tested type of conservation tillage seems to boost productivity during already good seasons, rather than stabilize harvests during poor rainfall seasons. Highlighting the challenges involved in upgrading these farming systems, we discuss the potential contribution of conservation tillage towards improved water availability in the crop root zone in a longer term perspective.  相似文献   
80.
基于物元分析法的土地健康评价——以湖北省枣阳市为例   总被引:1,自引:0,他引:1  
王菲  杨乐  马才学 《农业工程》2012,2(2):72-77
针对综合指数评价法存在的信息遗漏及主观等问题,该文采用物元分析法对湖北省枣阳市土地健康水平进行评价。在诠释土地生态安全概念的基础上,基于“生态—经济—社会”模式和层次分析法构建土地健康评价的指标体系,运用物元分析方法构建土地健康评价的综合评判模型,并以湖北省枣阳市为例进行了实证研究。研究结果表明:吴店镇和七方镇土地处于健康状态,新市镇和太平镇土地处于不健康状态,其他8乡镇土地处于亚健康状态。根据评价结果,该文提出相关政策建议,从而为枣阳市土地的健康、可持续利用提供指导。   相似文献   
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