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31.
目的 探讨大型密闭系统中几种共培养植物的光合效率等特性,为开展人与植物的物质交换实验提供基础数据.方法 利用受控生态生保系统集成实验平台植物舱开展常压下生菜等4种共培养色拉型蔬菜的光合效率研究.植物共培养面积为36.0 m2;采用Hoagland营养液培养;光源为90%红+10%蓝LED组合光源,光照强度为450μmol·m-2·s-1PPF,光照周期为24 h;根据植物不同生长阶段调节CO2浓度,控制范围为0.2% ~0.8%.结果 系统运行平稳,环境参数控制状态良好,植物生长状态基本正常;共培养植物产O2量和CO2吸收量平均分别为0.915 kg·d-1和1.204 kg·d-1,植物平均每天能产生约1.1人呼吸所需的O2,同时吸收其排出的CO2.结论 通过该实验,基本掌握植物共培养技术及系统放O2和吸收CO2的能力,可为开展多人多天的受控生态生保系统集成试验研究提供技术支持.  相似文献   
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Introduction The Cognitive Disabilities Model (CDM) is an occupational approach that can allow the classification of the functional-cognitive abilities of persons with addictions. The objective of the study was to explore the applicability of the ACLS-5 to assess a sample of persons undergoing addiction-rehabilitation treatment. Methods A sample of 232 participants was recruited from an outpatient treatment centre in Madrid (Spain). The ACLS-5, the Montreal Cognitive Assessment (MoCA), and the Prefrontal Symptom Inventory (PSI) were administered. Sociodemographic and addiction-related data were also obtained. Results Half of the sample showed serious deficits in functional cognition, which ultimately could be related to problems in their daily performance. Scores of ACLS-5 showed significant correlations with the severity of addiction, with those obtained with the MoCA, and with attentional symptoms on the PSI scale. Conclusions The data suggest the applicability of the ACLS-5 in assessing the degree of functional cognition in subjects treated for addiction, providing evidence to support ecological validity and facilitating the development of well-targeted cognitive rehabilitation programmes from an occupational perspective. The use of occupational-based instruments to assess the functioning of those with addictions is a requirement of occupational therapy professionals working in this general area.  相似文献   
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The metabolite of vitamin D, 1α,25-dihydroxyvitamin D3 (also known as calcitriol), is a biologically active molecule required to maintain the physiological functions of several target tissues in the human body from conception to adulthood. Its molecular mode of action ranges from immediate nongenomic responses to longer term mechanisms that exert persistent genomic effects. The genomic mechanisms of vitamin D action rely on cross talk between 1α,25-dihydroxyvitamin D3 signaling pathways and that of other growth factors or hormones that collectively regulate cell proliferation, differentiation and cell survival. In vitro and in vivo studies demonstrate a role for vitamin D (calcitriol) in modulating cellular growth and development. Vitamin D (calcitriol) acts as an antiproliferative agent in many tissues and significantly slows malignant cellular growth. Moreover, epidemiological studies have suggested that ultraviolet-B exposure can help reduce cancer risk and prevalence, indicating a potential role for vitamin D as a feasible agent to prevent cancer incidence and recurrence. With the preventive potential of this biologically active agent, we suggest that countries where cancer is on the rise—yet where sunlight and, hence, vitamin D may be easily acquired—adopt awareness, education and implementation strategies to increase supplementation with vitamin D in all age groups as a preventive measure to reduce cancer risk and prevalence.  相似文献   
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Integrating the conservation of biodiversity by smallholder farmers with agricultural intensification is increasingly recognized as a leading priority of sustainability and food security amid global environmental and socioeconomic change. An international research project investigated the smallholder agrobiodiversity of maize (corn) in a global hotspot (Bolivia) undergoing significant intensification. Peach-based intensification was pronounced (300–400%) and prolonged (2000–2010) in study areas. Intensification and maize agrobiodiversity were found to co-occur within smallholder landscapes. Interactions of these field systems did not trigger land-change tipping points leading to landrace extirpation. By 2010 maize landraces in the study areas still demonstrated high levels of taxonomic and ecological biodiversity and contributed significantly to this crop’s agrobiodiversity at national (31%) and hemispheric (3%) scales. Social and ecological resilience and in situ conservation of the maize agrobiodiversity by Bolivian smallholders was enabled through robust linkages to off-farm migration; resource access and asset capabilities among both traditional and nontraditional growers; landrace agroecology and food uses; and innovative knowledge and skills. The smallholders’ resilience resulting from these linkages was integral to the conditional success of the in situ conservation of maize agrobiodiversity. Environment–development interactions both enabled smallholders’ agrobiodiversity resilience and influenced the limits and vulnerability of agrobiodiversity. Scientific policy recommendations regarding land-use planning and sustainability analysis are targeted to specific Río+20 priorities for agrobiodiversity.  相似文献   
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The study examined associations between mothers’ upbringing background (kibbutz vs. home) and maternal-sensitive guidance of emotional conversations with their preschool children; children’s cooperation and exploration; and the coherence of their conversations. Using a quasi-experimental design, 112 children and their mothers (72 kibbutz raised, 40 home) completed the Autobiographical Emotional Event Dialogue. We hypothesized that maternal kibbutz upbringing would be associated to lower levels of mothers’ sensitive guidance of the conversations, children’s lower cooperation and exploration, and lower overall coherence. Results showed no upbringing-related differences for the mothers, but significant differences were found for the children, with children of kibbutz-raised mothers showing less cooperation and exploration, and lower levels of coherence for these dyads. The role of maternal background in shaping the interaction with their child is discussed.  相似文献   
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Objective: Ecological momentary assessment (EMA) methods have provided a rich assessment of the contextual factors associated with a wide range of behaviors including alcohol use, eating, physical activity, and smoking. Despite this rich database, this information has not been linked to specific locations in space. Such location information, which can now be easily acquired from global positioning system (GPS) tracking devices, could provide unique information regarding the space-time distribution of behaviors and new insights into their determinants. In a proof of concept study, we assessed the acceptability and feasibility of acquiring and combining EMA and GPS data from adult smokers with attention deficit hyperactivity disorder (ADHD). Methods: Participants were adults with ADHD who were enrolled in a larger EMA study on smoking and psychiatric symptoms. Among those enrolled in the latter study who were approached to participate (N = 11), 10 consented, provided daily EMA entries, and carried a GPS device with them during a 7-day assessment period to assess aspects of their smoking behavior. Results: The majority of those eligible to participate were willing to carry a GPS device and signed the consent (10 out of 11, 91%). Of the 10 who consented, 7 participants provided EMA entries and carried the GPS device with them daily for at least 70% of the sampling period. Data are presented on the spatial distribution of smoking episodes and ADHD symptoms on a subset of the sample to demonstrate applications of GPS data. Conclusions: We conclude by discussing how EMA and GPS might be used to study the ecology of smoking and make recommendations for future research and analysis.  相似文献   
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Abstract   This phenomenological study examined the impact of culture on the lived experience of women who were victims of intimate partner violence (IPV). The analysis of the data, using the method of Colaizzi, yielded three theme clusters: "living in misery", "enduring terror and sadness", and "no happy ending". They revealed the essential structure of living in a violent situation. The women, from diverse cultural backgrounds, had similar individual responses to violence. Although on a societal level, responses to violence are unique, the results revealed that women's responses were very personal and common across cultures, demonstrating their fundamental humanness. This finding underscores the importance of providing caring, individual support when working with victims of IPV, even though various cultures might perceive IPV differently. An ecological model for understanding the responses to IPV includes both individual and group perspectives related to IPV and the factors that influence the behavior of both women and men.  相似文献   
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