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21.
针对蓄电池生产线包封工序中存在大量手工上料,铅粉危害操作人健康,提出了极板自动上料的方案,分析比较 各方案的优缺点,设计了极板上料装置。极板上料装置投入运用后,解决了极板包片机上料的瓶颈,降低了工人劳动强 度,提高了劳动生产率  相似文献   
22.
我国生猪生产效率及补贴政策评价   总被引:7,自引:0,他引:7  
文章采用数据包络分析方法(DEA)分别对我国生猪生产效率进行了区域差异和规模比较。研究表明,生猪生产效率呈现出明显的地区差异,与西部地区比较,东部更有效率,但呈现规模不经济的状况;规模养殖比散养有较高的经济效率,但散养生猪仍具有较灵活的成本优势。根据研究结论,认为中国实施区域差别化的生猪补贴扶持政策有一定的合理性,但应有侧重,东部应侧重效率导向,中西部地区应以规模导向为主;同时在发展规模化养殖过程中也应注意差异化,对不同规模养殖户实行差别的补贴政策;生猪补贴政策还应充分考虑生产和消费布局等。  相似文献   
23.
目的探讨改良鼻饲法对老年危重症患者胃肠内营养并发症的影响。方法采用传统鼻饲法(对照组)与改良鼻饲法(试验组)进行老年危重症患者胃肠内营养支持,对并发症比较。试验组采用能全力营养素接输血管持续滴注方法鼻饲,对照组采用传统方法鼻饲(营养液同试验组),比较两组鼻饲后胃肠道并发症(呕吐和返流、误吸、腹胀、腹泻、消化道出血、便秘)发生率。结果鼻饲后胃肠道并发症发生率试验组明显低于对照组(P〈0.05)。结论能全力营养素液持续滴注鼻饲法可安全用于老年危重症患者,且对维持胃肠道结构和功能、减少并发症、促进营养状态和改善预后有显著临床意义,能明显提高护理工作效率。  相似文献   
24.
ProblemSome women who intend to breastfeed experience a breastfeeding aversion response (BAR) while breastfeeding.BackgroundLittle is known about the experience of those who have feelings of aversion while breastfeeding.AimThis study aimed to investigate the experiences of women who have an aversion response to breastfeeding while their infant is latched at the breast. This is the first study that aims to understand this breastfeeding aversion response (BAR) as described by women who experience this phenomenon.MethodsInterpretative phenomenological analysis (IPA) was used to conduct and analyse ten semi-structured in-depth interviews with women who self-identified as experiencing BAR.FindingsFour overarching themes were identified: (1) Involuntary, strong sensations of aversion in response to the act of breastfeeding, (2) Internal conflict and effects on maternal identity, (3) The connection between BAR and relationships with others, and (4) Reflections on coping with BAR and building resilience.DiscussionSome women who intend to breastfeed can experience BAR, and this negative sensation conflicts with their desire to breastfeed. BAR can impact on maternal wellbeing. Those who experience BAR may benefit from person-centred support that directly addresses the challenges associated with BAR to achieve their personal breastfeeding goals.ConclusionThe experience of BAR is unexpected and difficult for mothers. If support is not available, BAR can have detrimental effects on maternal identity, mother–child bonds, and intimate family relationships.  相似文献   
25.
辽宁生猪生产:30年波动分析与发展建议   总被引:2,自引:0,他引:2  
辽宁省生猪养殖业作为畜牧业的重要组成部分,已经发展成为农业和农村的支柱产业。依据辽宁省30年生猪生产的历史数据,以生产波动的相关理论,运用回归分析对猪肉产量进行时间趋势拟合,得出辽宁生猪生产波动特征:长期表现为总量增长,短期呈明显周期性波动。生猪价格、利润周期、疫病发生的不确定性和农户饲养规模是产生短期波动的主要因素。结合周期波动分析,提出建立生猪期货市场,实现生猪规模化饲养,健全完善生猪疫病防控体系,加强宏观政策引导等辽宁生猪生产发展建议。  相似文献   
26.
本文主要介绍在数控铣削加工沟槽时,如何利用刀具半径补偿功能,使刀具偏离工件沟槽轮廓一定距离,实现利用一个程序完成沟槽内、外轮廓粗、精加工,以及选用合适的下刀方式进行沟槽加工质量控制,并用宏指令进行编程。  相似文献   
27.
The costs and benefits of a HIV/AIDS PMTCT program in a Mozambican city were calculated. The provision and non-provision of infant feeding formula were considered, along with voluntary counselling and testing, and anti-retroviral treatment with Nevirapine. Costs were calculated in monetary units and benefits as deaths averted and disability-adjusted life years. The UNAIDS cost-effectiveness tool for evaluating ARV drug and substitute feeding interventions was used. The costs of the program were compared with the costs of treating HIV-infected children. With no infant feeding formula, there would be a total savings of US$5242 and a negative cost per DALY of US$1.53 without infant feeding formula. With formula, net annual costs would be US$141,268 and cost per DALY US$38.69. Citywide, each year 132 infant deaths would be averted by use of Nevirapine and eight averted by the breastmilk replacement program. All program options have reasonable cost-effectiveness ratios.  相似文献   
28.
本文对抚州地区12种农田两栖动物进行了食性分析,对泽蛙胃内容物的检查表明;其捕食种类达4门7纲16目33种以上,且以膜翅目,鞘翅目,鳞翅目的昆虫和蜘蛛为主,有益多数达60.14%,其他11种多以农业害虫为食,其中饰纹姬蛙,小弧斑姬蛙以蚂蚁为主食,这些结果表明,这12种两栖类是农业的效益,应加保护。  相似文献   
29.
Data from a human feeding trial with healthy men were used to develop a dose-response model for 13 strains of Salmonella and to determine the effects of strain variation on the shape of the dose-response curve. Dose-response data for individual strains were fit to a three-phase linear model to determine minimum, median, and maximum illness doses, which were used to define Pert distributions in a computer simulation model. Pert distributions for illness dose of individual strains were combined in an Excel spreadsheet using a discrete distribution to model strain prevalence. In addition, a discrete distribution was used to model dose groups and thus create a model that simulated human feeding trials. During simulation of the model with @Risk, an illness dose and a dose consumed were randomly assigned to each consumption event in the simulated feeding trial and if the illness dose was greater than the dose consumed then the model predicted no illness, otherwise the model predicted that an illness would occur. To verify the dose-response model predictions, the original feeding trial was simulated. The dose-response model predicted a median of 69 (range of 43-101) illnesses compared to 74 in the original trial. Thus, its predictions were in agreement with the data used to develop it. However, predictions of the model are only valid for eggnog, healthy men, and the strains and doses of Salmonella used to develop it. When multiple strains of Salmonella were simulated together, the predicted dose-response curves were irregular in shape. Thus, the sigmoid shape of dose-response curves in feeding trials with one strain of Salmonella may not accurately reflect dose response in naturally contaminated food where multiple strains may be present.  相似文献   
30.
This paper describes the results of two studies concerning a programme to prevent mother-to-child transmission of HIV in Botswana. The programme included VCT, provision of oral AZT to the HIV infected mothers and to the infant, infant feeding counselling and support, and free provision of formula for infants of HIV infected mothers who opted not to breastfeed. The study evaluating the pilot phase of the programme concluded that the programme should be scaled up. After the programme expanded, a follow-up evaluation of infant feeding practices was conducted. Infant feeding practices differed significantly between intervention and non-intervention sites and between mothers of unknown HIV status, non-infected mothers and HIV-infected mothers. Among the infected mothers who chose exclusive formula feeding, 96% maintained this up to the time of interview. Health workers' knowledge about HIV transmission was weak. Counselling on feeding needs to be improved in many areas.  相似文献   
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