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121.
Major Depressive Disorder (MDD) in adolescents is characterized by alterations in positive emotions and reward processing. Recent investigations using functional magnetic resonance imaging (fMRI) find depression-related differences in reward anticipation. However, it is unknown whether feedback influences subsequent reward anticipation, which may highlight the context of reward processing. Ten youth with MDD and 16 youth with no history of MDD completed an fMRI assessment using a reward task. Reward anticipation was indexed by blood oxygen level dependent signal change in the striatum following winning, losing, non-winning, and non-losing outcomes. A significant interaction between diagnostic status and outcome condition predicted reward anticipation in the caudate. Decomposition of the interaction indicated that following winning outcomes, depressed youth demonstrated reduced reward anticipation relative to healthy youth. However, no significant differences between depressed and healthy youth were found after other outcomes. Reward anticipation is altered following winning outcomes. This finding has implications for understanding the developmental pathophysiology of MDD and suggests specific contexts where altered motivational system functioning may play a role in maintaining depression.  相似文献   
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Loneliness has been shown to have direct effects on one’s personal well-being. Specifically, a greater feeling of loneliness is associated with negative mental health outcomes, negative health behaviors, and an increased likelihood of premature mortality. Using the neuroendocrine hypothesis, we expected social inclusion to predict decreases in both blood glucose levels and low-density lipoproteins (LDLs) and increases in high-density lipoproteins (HDLs). Fifty-two healthy adults provided self-report data for social inclusion and blood samples for hematological tests. Results indicated that higher social inclusion predicted lower levels of blood glucose and LDL, but had no effect on HDL. Implications for theory and practice are discussed.  相似文献   
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We developed a sensitive and specific sodB-based quantitative PCR assay to detect Ehrlichia spp. The assay''s limit of detection was 5 copies/reaction, and it did not amplify nonspecific DNA. Compared with a 16S rRNA gene PCR target, the sodB target may offer an improved molecular diagnostic assay to detect Ehrlichia spp.  相似文献   
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We examined whether the addition of community-based accompaniment to Rwanda’s national model for antiretroviral treatment (ART) was associated with greater improvements in patients’ psychosocial health outcomes during the first year of therapy. We enrolled 610 HIV-infected adults with CD4 cell counts under 350 cells/μL initiating ART in one of two programs. Both programs provided ART and required patients to identify a treatment buddy per national protocols. Patients in one program additionally received nutritional and socioeconomic supplements, and daily home-visits by a community health worker (“accompagnateur”) who provided social support and directly-observed ingestion of medication. The addition of community-based accompaniment was associated with an additional 44.3 % reduction in prevalence of depression, more than twice the gains in perceived physical and mental health quality of life, and increased perceived social support in the first year of treatment. Community-based accompaniment may represent an important intervention in HIV-infected populations with prevalent mental health morbidity.  相似文献   
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ABSTRACT: BACKGROUND: Recreational facilities are an important community resource for health promotion because they provide access to affordable physical activities. However, despite their health mandate, many have unhealthy food environments that may paradoxically increase the risk of childhood obesity. The Alberta Nutrition Guidelines for Children and Youth (ANGCY) are government-initiated, voluntary guidelines intended to facilitate children's access to healthy food and beverage choices in schools, childcare and recreational facilities, however few recreational facilities are using them. METHODS: We used mixed methods within an exploratory multiple case study to examine factors that influenced adoption and implementation of the ANGCY and the nature of the food environment within three cases: an adopter, a semi-adopter and a non-adopter of the ANGCY. Diffusion of Innovations theory provided the theoretical platform for the study. Qualitative data were generated through interviews, observations, and document reviews, and were analysed using directed content analysis. Set theoretic logic was used to identify factors that differentiated adopters from the non-adopter. Quantitative sales data were also collected, and the quality of the food environment was scored using four complementary tools. RESULTS: The keys to adoption and implementation of nutrition guidelines in recreational facilities related to the managers' nutrition-related knowledge, beliefs and perceptions, as these shaped his decisions and actions. The manager, however, could not accomplish adoption and implementation alone. Intersectoral linkages with schools and formal, health promoting partnerships with industry were also important for adoption and implementation to occur. The food environment in facilities that had adopted the ANGCY did not appear to be superior to the food environment in facilities that had not adopted the ANGCY. CONCLUSIONS: ANGCY uptake may continue to falter under the current voluntary approach, as the environmental supports for voluntary action are poor. Where ANGCY uptake does occur, changes to the food environment may be relatively minor. Stronger government measures may be needed to require recreational facilities to improve their food environments and to limit availability of unhealthy foods.  相似文献   
129.
Prenatal exposure to chlorpyrifos (CPF), an organophosphorus insecticide, has long been associated with delayed neurocognitive development and most recently with decrements in working memory at age 7. In the current paper, we expanded the previous work on CPF to investigate how additional biological and social environmental factors might create or explain differential neurodevelopmental susceptibility, focusing on main and moderating effects of the quality of the home environment (HOME) and child sex. We evaluate how the quality of the home environment (specifically, parental nurturance and environmental stimulation) and child sex interact with the adverse effects of prenatal CPF exposure on working memory at child age 7years. We did not observe a remediating effect of a high quality home environment (either parental nurturance or environmental stimulation) on the adverse effects of prenatal CPF exposure on working memory. However, we detected a borderline significant interaction between prenatal exposure to CPF and child sex (B (95% CI) for interaction term=-1.714 (-3.753 to 0.326)) suggesting males experience a greater decrement in working memory than females following prenatal CPF exposure. In addition, we detected a borderline interaction between parental nurturance and child sex (B (95% CI) for interaction term=1.490 (-0.518 to 3.499)) suggesting that, in terms of working memory, males benefit more from a nurturing environment than females. To our knowledge, this is the first investigation into factors that may inform an intervention strategy to reduce or reverse the cognitive deficits resulting from prenatal CPF exposure.  相似文献   
130.
Nematodes as bioindicators of soil degradation due to heavy metals   总被引:1,自引:0,他引:1  
The effect of distance from a heavy metal pollution source on the soil nematode community was investigated on four sampling sites along an 4?km transect originating at the Kovohuty a.s. Krompachy (pollution source). The soil nematode communities were exposed to heavy metal influence directly and through soil properties changes. We quantified the relative effects of total and mobile fraction of metals (As, Cd, Cr, Cu, Pb, and Zn) on soil ecosystem using the nematode community structure (trophic and c-p groups,) and ecological indices (Richness of genera, H′, MI2-5, etc.). Pollution effects on the community structure of soil free living nematodes was found to be the highest near the pollution source, with relatively low population density and domination of insensitive taxa. A decrease in heavy metals contents along the transect was linked with an increase in complexity of nematode community. The majority of used indices (MI2-5, SI, H′) negatively correlated (P?<?0.05 or P?<?0.01) with heavy metals content and were sensitive to soil ecosystem disturbance. Contamination by heavy metals has negatively affected the soil environment, which resulted in nematode community structure and ecological indices changes. Results showed that the free-living nematodes are useful tools for bioindication of contamination and could be used as an alternative to the common approaches based on chemical methods.  相似文献   
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