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The goal of this study was to develop and subsequently evaluate the internal construct and criterion-related validity of the Preschool Imitation and Praxis Scale (PIPS). Different task characteristics were selected considered to be important as unravelled in research in apraxic adults to tap a broad range of possible imitation mechanisms. Participants included 498 children without disabilities (1–4.9 years) and 47 children with autism spectrum disorders (ASD) (1.9–4.5 years). Exploratory factor analysis disclosed 4 dimensions in the scale, labelled: goal directed versus non-goal directed procedural imitation and single versus sequential bodily imitation. Internal consistency for the PIPS scale (α = .97) and subscales was high (α ranged from .79 to .96). In both samples, the PIPS scale score was strongly related to age (r = .78, respectively r = .56). Significant relationships between the PIPS score and mental, language, motor ages in the ASD sample supported criterion-related validity (r ranged from .59 to .74). The PIPS appears to have fundamentally sound psychometric characteristics, although more research is needed.  相似文献   
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Oral anticoagulant therapy, which is used for prophylaxis and management of thrombotic disorders, causes similar reductions in plasma levels of vitamin K-dependent procoagulant and anticoagulant clotting factor zymogens. When we measured levels of circulating activated protein C, a physiologically important anticoagulant and anti-inflammatory agent, in patients on oral anticoagulant therapy, the results unexpectedly showed that such therapy decreases levels of activated protein C substantially less than levels of protein C, prothrombin, and factor X, especially at lower levels of prothrombin and factor X. Thus, we suggest that oral anticoagulant therapy results in a relatively increased expression of the protein C pathway compared with procoagulant pathways not only because there is less prothrombin to inhibit activated protein C anticoagulant activity, but also because there is a disproportionately higher level of circulating activated protein C.  相似文献   
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Background  The study of vitamin D status at population level gained relevance since vitamin D deficiency was recently suggested to trigger chronic disease. Aim of the study  We aimed to describe vitamin D status, its association with bone and mineral metabolism and risk factors for deficiency in adults over 40 years in Belgium. Methods  We conducted a cross-sectional survey in a stratified random sample of 401 subjects aged between 40 and 60 years living in Brussels, and drawn from 4 different ethnic backgrounds: autochthonous Belgian, Moroccan, Turkish and Congolese. 25-Hydroxyvitamin D (25OHD), parathyroid hormone (PTH), osteocalcin, C-telopeptide and bone mineral density was measured. Results  Three-hundred and six subjects (77%) showed 25OHD concentrations below 50 nmol/l,135 (34%) below 25 nmol/l and 18 (5%) below 12.5 nmol/l. The proportion of subjects with vitamin D deficiency was four times greater amongst those of Moroccan or Turkish descent compared with those of Congolese or Belgian descent. Moroccan subjects showed a significant higher PTH and bone marker concentrations compared to Belgian. Ethnicity, season and sex were independently associated with vitamin D deficiency in multivariate analysis. Conclusion  The prevalence of vitamin D deficiency is very high amongst the adult population of Brussels but immigrants are at greater risk. Given the established link between population health and adequate vitamin D status, a policy of vitamin D supplementation should be considered in these risk groups.  相似文献   
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In vivo inoculation of a low metastatic BW 5147 derived T-cell lymphoma variant into syngeneic mice, had led to the generation of a highly metastatic variant. The shift towards a more metastatic phenotype is accompanied by an increase in major histocompatibility class I H-2Dk antigen expression. This suggests that H-2Dk antigens may control the metastatic potential of BW T lymphoma cells. Our present findings indicate that H-2Dk expression is directly correlated with the metastatic potential of BW cells. We have confirmed such correlation by specifically altering the level of H-2Dk expression by: I) FACS analysis, 2) IFN-γ treatment, 3) H-2Dk gene transfection. Cells sorted for low H-2Dk expression had a significantly reduced metastatic potential. Induction of H-2Dk expression on these cells by either IFN-γ treatment or H-2Dk gene transfection concomitantly led to increased metastasis. We also assessed metastatic potential of BW cells in irradiated, immunocompromised recipients. Our results show that the immune system is implicated and we further tested which immune effectors are involved, In vivo depletion of natural killer (NK) and CD8+ T-cells revealed that the difference in metastatic potential of the H-2Dk variants relies upon an NK-dependent mechanism, whereas CD8+ T-cells are not implicated. Our observations suggest that highly metastatic cells, expressing a high level of H-2Dk antigens are more resistant to NK-cell-mediated cytotoxicity in vivo. We have confirmed our in vivo results by in vitro cytotoxicity assays using poly I:C induced NK and IL-2 activated LAK cells. We conclude that a NK-dependent mechanism accounts for the association between differential H-2Dk antigen expression and metastasis.  相似文献   
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ObJECTIVE: To assess the knowledge, attitudes and practices with regard to female genital mutilation (FGM) among gynaecologists in Flanders, Belgium. METHODS: A questionnaire-based survey was sent to 724 Flemish gynaecologists and trainees. RESULTS: Three-hundred-and-thirty-four questionnaires were returned. The survey revealed gaps in the knowledge of FGM and the provision of care by Flemish gynaecologists to women who had been mutilated. It also appeared that FGM was not properly addressed in the basic and specialized medical training in Flanders, that little was known about codes of conduct issued by the hospitals when these were not lacking altogether, and that knowledge about legislation concerning FGM was deficient. There was much confusion whether re-infibulation is authorized, and what its legal status is. Some respondents considered cosmetic vaginal surgery as a form of FGM and many were in favour of the medicalization of FGM. Gynaecologists were most commonly confronted with complaints related to sexual problems caused by FGM. Finally, the study also showed that only about a third of the gynaecologists were discouraging women from having their daughters excised. CONCLUSION: There is a need for a thorough discussion among all those concerned of the ethical and legal aspects of re-infibulation, medicalization of FGM and cosmetic vaginal surgery.  相似文献   
78.
The PCR-ELISA represents a promising advance for diagnosis of visceral leishmaniasis (VL) in blood samples. However, the method has been validated mostly with HIV-positive patients who are known to have high levels of parasitaemia. We developed a new PCR-ELISA assay for specific detection of Leishmania in patients' blood and validated it in Nepalese subjects with clinically suspected VL, almost all of whom were HIV-negative. For blood samples, PCR-ELISA was more sensitive (83.9%) than conventional PCR (73.2%), and demonstrated 100% and 87.2% specificity when using healthy controls who had never travelled to a VL-endemic area and controls from a VL-endemic area as references, respectively. We have demonstrated the ability of PCR-ELISA to detect parasites in blood of HIV-negative patients. The method could be used for epidemiological as well as clinical purposes, as it reduces the need for traumatic bone marrow sampling and risky spleen aspiration.  相似文献   
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BACKGROUND: Cardiac arrest and cardiopulmonary resuscitation may result in multiorgan damage after global hypoxia due to neutrophil recruitment. Patients display all signs of a systemic inflammatory response syndrome. Reducing neutrophil recruitment may thus preserve organ function. METHODS: Mice were subjected to cardiac arrest and resuscitation. CD18/CD11b expression on circulating neutrophils was assessed by flow cytometry. Intercellular adhesion molecule-1 expression was analyzed by Western blot and immunofluorescence. Neutrophil recruitment was quantified by immunohistochemistry. Neurologic function was assessed by a balance test. For liver and kidney function, plasma alanine aminotransferase activity and creatinine concentrations were determined. To reduce neutrophil recruitment, mice received 100 microg anti-intercellular adhesion molecule-1 antibody intraperitoneally. RESULTS: Resuscitation led to severe hypoxia, acidosis, and hypercarbia. Adhesion molecule expression and neutrophil recruitment were increased in the liver, kidney, and brain. Neurologic performance was impaired 24 h after cardiac arrest. Creatinine and alanine aminotransferase concentrations were significantly increased. Immunoneutralization of intercellular adhesion molecule-1 attenuated neutrophil influx in the liver along with alanine aminotransferase activity, whereas creatinine concentrations and neutrophil influx in the kidney remained unchanged. Neurologic function was improved in the treatment group. CONCLUSIONS: Global hypoxia induces activation of the endothelium in the brain, liver, and kidney. The resulting damage to the brain and liver are due to infiltration of neutrophils, whereas kidney damage is not, because reduction of neutrophil recruitment after cardiopulmonary resuscitation improves recovery of neurologic and hepatic but not renal function. Inhibition of intercellular adhesion molecule-1 after global hypoxia may be beneficial in patients experiencing cardiac arrest and resuscitation.  相似文献   
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