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61.
The tumour microenvironment is complex containing not only neoplastic cells but also a variety of host cells. The heterogeneous infiltrating immune cells include subsets of cells with opposing functions, whose activities are mediated either directly or through the cytokines they produce. Systemic delivery of cytokines such as interleukin‐2 ( IL‐2) has been used clinically to enhance anti‐tumour responses, but these molecules are generally thought to have evolved to act locally in a paracrine fashion. In this study we examined the effect of local production of IL‐2 on the growth and the immune response to B16 melanoma cells. We found that the local production of IL‐2 enhances the number of interferon‐γ‐expressing CD8 T and natural killer cells in the tumour, as well as inducing expression of vascular cell adhesion molecule 1 on tumour vessels. These responses were largely absent in interferon‐γ knockout mice. The expression of IL‐2 in the tumour microenvironment decreases tumour growth despite also enhancing Foxp3+ CD4+ regulatory T cells and anti‐inflammatory cytokines such as IL‐10. Higher levels of IL‐2 in the tumour microenvironment eliminated the progressive growth of the B16 cells in vivo, and this inhibition was dependent on the presence of either T cells or, to a lesser extent, natural killer cells. Surprisingly however, the B16 tumours were not completely eliminated but instead were controlled for an extended period of time, suggesting that a form of tumour dormancy was established.  相似文献   
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Community Mental Health Journal - The mortality disparity for persons with schizophrenia spectrum disorders (SSDs) due to cardiovascular disease is a devastating problem. Many risk factors are...  相似文献   
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Despite the evidence suggesting that all treatments intended to be therapeutic are equally efficacious, the conjecture that one form of treatment, namely cognitive-behavioral therapy (CBT), is superior to all other treatment persists. The purpose of the current study was to (a) reanalyze the clinical trials from an earlier meta-analysis that compared CBT to ‘other therapies’ for depression and anxiety (viz., Tolin, 2010) and (b) conduct a methodologically rigorous and comprehensive meta-analysis to determine the relative efficacy of CBT and bona fide non-CBT treatments for adult anxiety disorders. Although the reanalysis was consistent with the earlier meta-analysis' findings of small to medium effect sizes for disorder-specific symptom measures, the reanalysis revealed no evidence for the superiority of CBT for depression and anxiety for outcomes that were not disorder-specific. Following the reanalysis, a comprehensive anxiety meta-analysis that utilized a survey of 91 CBT experts from the Association of Behavioral and Cognitive Therapists (ABCT) to consensually identify CBT treatments was conducted. Thirteen clinical trials met the inclusion criteria. There were no differences between CBT treatments and bona fide non-CBT treatments across disorder-specific and non-disorder specific symptom measures. These analyses, in combination with previous meta-analytic findings, fail to provide corroborative evidence for the conjecture that CBT is superior to bona fide non-CBT treatments.  相似文献   
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The influence of early relational experience on later social understanding has evoked rich theoretical discussion but relatively little empirical inquiry. Enlisting data from the NICHD Study of Early Child Care and Youth Development, measures of the security of attachment in infancy, toddlerhood, and early childhood, together with measures of parenting quality (maternal sensitivity and depressive symptoms) gathered longitudinally throughout infancy and early childhood, were used to predict differences in children's thoughts and feelings about peers (i.e., social problem solving, negative attributional biases, aggressive solutions to ambiguous social situations, and self-reported loneliness) when children were 54 months and in first grade. Relational experiences, especially before 36 months, were significantly predictive of later peer-related representations. Attachment security at 24 and 36 months was associated with enhanced social problem-solving skills and less loneliness, but security of attachment at 15 months was nonpredictive. Early maternal sensitivity was positively associated with later social problem-solving and negatively with aggressive responses, and early maternal depressive symptoms were positively associated with children's negative attributions. Concurrent parenting quality was also associated with children's thoughts and feelings about peers, but less consistently. These findings shed new light on how early relational experiences may contribute to social information processing with peers at the end of the preschool years, and that the timing of relational influences may be crucial.  相似文献   
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Deciding to test for HIV is necessary for receiving HIV treatment and care among those who are HIV-positive. This article presents a systematic review of quantitative studies on relationships between psychological (cognitive and affective) variables and HIV testing. Sixty two studies were included (fifty six cross sectional). Most measured lifetime testing. HIV knowledge, risk perception and stigma were the most commonly measured psychological variables. Meta-analysis was carried out on the relationships between HIV knowledge and testing, and HIV risk perception and testing. Both relationships were positive and significant, representing small effects (HIV knowledge, d = 0.22, 95 % CI 0.14–0.31, p < 0.001; HIV risk perception, OR 1.47, 95 % CI 1.26–1.67, p < 0.001). Other variables with a majority of studies showing a relationship with HIV testing included: perceived testing benefits, testing fear, perceived behavioural control/self-efficacy, knowledge of testing sites, prejudiced attitudes towards people living with HIV, and knowing someone with HIV. Research and practice implications are outlined.  相似文献   
69.
PPT1 and PPT2 encode two lysosomal thioesterases that catalyze the hydrolysis of long chain fatty acyl CoAs. In addition to this function, PPT1 (palmitoyl-protein thioesterase 1) hydrolyzes fatty acids from modified cysteine residues in proteins that are undergoing degradation in the lysosome. PPT1 deficiency in humans causes a neurodegenerative disorder, infantile neuronal ceroid lipofuscinosis (also known as infantile Batten disease). In the current work, we engineered disruptions in the PPT1 and PPT2 genes to create "knockout" mice that were deficient in either enzyme. Both lines of mice were viable and fertile. However, both lines developed spasticity (a "clasping" phenotype) at a median age of 21 wk and 29 wk, respectively. Motor abnormalities progressed in the PPT1 knockout mice, leading to death by 10 mo of age. In contrast, the majority of PPT2 mice were alive at 12 mo. Myoclonic jerking and seizures were prominent in the PPT1 mice. Autofluorescent storage material was striking throughout the brains of both strains of mice. Neuronal loss and apoptosis were particularly prominent in PPT1-deficient brains. These studies provide a mouse model for infantile neuronal ceroid lipofuscinosis and further suggest that PPT2 serves a role in the brain that is not carried out by PPT1.  相似文献   
70.
Dietary cholesterol regulation of cholesterol 7alpha-hydroxylase (Cyp7a1), the rate-limiting enzyme in the classical pathway of bile acid synthesis, has been implicated in plasma cholesterol responsiveness. In the current study, the effects of 0.0% and 0.5% cholesterol diets were examined in Cyp7a1 knockout (KO), heterozygous Cyp7a1 KO (Het), and human Cyp7a1 transgenic mice on the mouse Cyp7a1 KO background (Tg+KO). We confirmed previous findings that dietary cholesterol increased mouse Cyp7a1 activity in Het mice but decreased human Cyp7a1 activity in Tg+KO mice. However, in both Het and Tg+KO mice, dietary cholesterol increased bile acid pool size (36% and 72%, respectively) and fecal bile acid excretion (2.2- and 3.6-fold, respectively). The expression of cholesterol 27-hydroxylase (Cyp27), the major enzyme of the alternative pathway of bile acid synthesis, was not significantly different in cholesterol-fed KO, Het, or Tg+KO mice. Furthermore, dietary cholesterol had comparable effects on total plasma cholesterol and non-high-density lipoprotein cholesterol in KO, Het, and Tg+KO mice. Thus, in Tg+KO mice, dietary cholesterol regulates bile acid pool size, fecal bile acid excretion, and plasma cholesterol independently of Cyp7a1 activity. These results challenge the notion that dietary cholesterol regulation of Cyp7a1 is a major determinant of plasma cholesterol responsiveness.  相似文献   
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