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101.
Clinical Rheumatology - The associations between fatigue and disease activity in patients with rheumatoid arthritis (RA) have not been defined. The present objectives were to explore in RA patients...  相似文献   
102.
Summary The induction of lupus-like syndromes with the appearance of single-stranded DNA antibodies is a well-known complication of drug therapy. In this report we present a patient with an erosive seropositive rheumatoid arthritis developing the clinical and serological features of systemic lupus erythematosus including the occurrence of double-stranded DNA antibodies under sulfasalazine treatment.  相似文献   
103.
PURPOSE: To measure common femoral artery (CFA) diameters in infants and children referred for cardiac catheterization and investigate if CFA diameters can be predicted upon the basis of age, body mass index (BMI), and height. METHODS: CFA diameters were measured in 84 infants and children (50 boys; age range 1- 220 months) referred for diagnostic or therapeutic cardiac interventions. Sonographic measurements were made in a supine position utilizing a 7.5-MHz linear transducer; diameters were defined as the intima to intima distance. Age was described in months and height in centimeters. The Spearman correlation coefficient (rho) was used to test the similarity of diameters between sides; the Pearson correlation coefficient (r) was used to analyze the influence of age, height, and BMI on CFA diameter. RESULTS: Diameters of the right and left CFA were similar (rho=0.951). Age and height were highly correlated (rho=0.956), but not BMI and height (rho=0.279). The best model was CFA diameter = -0.838 + 0.031 height + 0.046 BMI. Height was the most relevant determinant for CFA diameter (p<0.0001, 90% CI 0.027 to 0.036; BMI: p=0.093, 90% CI 0.001 to 0.090, and the intercept: p=0.032, 90% CI-1.475 to-0.200). CONCLUSIONS: Common femoral artery diameter can be sufficiently predicted from height and BMI of infants and children prior to femoral catheterization or surgical reconstruction.  相似文献   
104.
AIMS: To compare the predictive value of inflammatory biomarkers and lipids for vascular and non-vascular mortality in older men. METHODS AND RESULTS: The relevance of inflammatory biomarkers and lipids for vascular and non-vascular mortality was assessed in a prospective study of 5360 men (mean age 77 years) followed for 7 years. Vascular mortality was positively associated with log C-reactive protein (lnCRP), fibrinogen and total/HDL-C (high-density lipoprotein cholesterol), and inversely associated with albumin [age adjusted hazard ratio (HR) per 2-SD higher usual level (approximately the difference between the top and the bottom thirds of the distribution): 2.09 for lnCRP; 1.70 for fibrinogen; 0.50 for albumin and 1.45 for total/HDL-C]. The associations with the inflammatory markers were attenuated after adjustment for established risk factors, including lipids [adjusted HRs: 1.86 (lnCRP); 1.44 (fibrinogen); 0.51 (albumin)], and further attenuated (and, for fibrinogen, no longer predictive) after adjustment for each other [fully adjusted HRs: 1.60 (lnCRP); 1.01 (fibrinogen); 0.61 (albumin)]. Higher CRP and lower albumin levels were also associated with significantly raised non-vascular mortality independently of other characteristics [fully adjusted HRs: 1.62 (lnCRP); 0.65 (albumin)]. CONCLUSION: In this cohort of older men, higher CRP and lower albumin levels strongly predicted both vascular and non-vascular mortality, independently of other characteristics.  相似文献   
105.
106.
CONTEXT: Dehydroepiandrosterone (DHEA) mainly exerts indirect action via downstream conversion toward sex steroids within peripheral target cells including immune cells. In vitro DHEA has been shown to enhance IL-2 release from T lymphocytes, whereas it inhibits IL-6 secretion. Conversely, aging is associated with a decline in both DHEA and IL-2, whereas IL-6 increases. OBJECTIVE: The objective of the study was to investigate age-related differences in expression and functional activity of steroidogenic enzymes involved in downstream conversion of DHEA in peripheral blood mononuclear cells (PBMCs). DESIGN: This study was cross-sectional. PARTICIPANTS/SETTING: Healthy young men (n = 8; age range, 23-29 yr) and healthy middle-aged men (n = 8; age range, 52-66 yr) were studied in an academic setting. MEASURES: mRNA expression of steroidogenic enzymes in PBMCs was measured by qualitative and quantitative RT-PCR analysis and enzyme activity assays after incubation of PBMCs with radiolabeled DHEA, 4-androstene-3,17-dione (androstenedione), and testosterone. RESULTS: RT-PCR analysis showed expression of all enzymes required for DHEA conversion toward active androgens and to the immune-stimulatory metabolite androstenediol. Steroid conversion patterns indicated a particularly increased activity of 17beta-hydroxysteroid dehydrogenase type 5 (17beta-HSD5) in the older men, demonstrated by significantly higher conversion rates of DHEA to androstenediol and of androstenedione to testosterone (all P < 0.05). By contrast, conversion of DHEA to androstenedione via 3beta-HSD occurred at a similar rate. Quantitative RT-PCR analysis revealed increased expression of 17beta-HSD 5 mRNA in PBMCs from the older men. CONCLUSIONS: Our results provide evidence for significant changes in sex steroid metabolism by human PBMCs with aging, which may represent an endocrine link to immune senescence.  相似文献   
107.
NK cells are innate lymphocytes that play a key role in the control of various viral infections. Recent studies indicate that NK cells may acquire some features of adaptive immune cells, including the formation of long‐lived memory cells. A large and growing body of data indicates that NK cells regulate the adaptive immune response as well. The function and the activation status of NK cells are tightly regulated by signals induced by a broad range of inhibitory and activating cell surface receptors and cytokines released by other immune cells. Here, we review the function of mouse NK‐cell receptors involved in virus control and in the regulation of the adaptive immune response. In addition, we discuss viral strategies used to evade NK‐cell‐mediated control during infection. Finally, the role of several activating Ly49 receptors specific for mouse cytomegalovirus (MCMV), as well as some controversial issues in the field, will be discussed.  相似文献   
108.

Background

Changes in circulatory aminopeptidases [dipeptidyl-peptidase-IV (DPP-IV), Prolyl-oligopeptidase (POP) and Leucine aminopeptidase (LAP)] activities have been found to be associated with psychiatric illnesses and inflammatory diseases.

Methods

The discriminatory indices of aminopeptidases activities were assessed by enzymatic assays in plasma samples from 240 unipolar depression (UD) patients and 264 matched controls. In addition the relationship between soluble and cellular DPP-IV activity was determined in plasma and blood cells from healthy subjects.

Results

Greater than 95% of the plasma DPP-IV activity could be blocked by inhibitors, demonstrating the specificity of the assay. Also, DPP-IV protein and activity levels were strongly correlated. In contrast, only 50% of the membrane-bound activity in blood cells was inhibited, which suggested that other similar peptidases may be present in these cells. UD patients had decreased plasma levels of DPP-IV and POP activities compared to healthy controls with a concomitant increase in LAP activity. Finally, testing of the LAP/DPP-IV ratio resulted in good discrimination of UD patients from controls with an area under the curve—receiver operating characteristic of 0.70.

Limitations

Further biological validation studies using different cohorts are warranted.

Conclusions

The finding that plasma DPP-IV activity was decreased and LAP activity was increased in UD patients suggests the potential value for testing the levels of these enzymes for improved classification of patients. In addition, the changes in these enzymes, suggests that the proteolytic maturation of their proneuropeptide and prohormone subtrates may also be affected in UD, resulting in altered production of the associated bioactive peptides.  相似文献   
109.
Low-frequency repetitive transcranial magnetic stimulation (rTMS) of the auditory cortex has been shown to significantly reduce tinnitus severity in some patients. There is growing evidence that a neural network of both auditory and non-auditory cortical areas is involved in the pathophysiology of chronic subjective tinnitus. Targeting several core regions of this network by rTMS might constitute a promising strategy to enhance treatment effects. This study intends to test the effects of a multisite rTMS protocol on tinnitus severity. 45 patients with chronic tinnitus were treated with multisite stimulation (left dorsolateral prefrontal, 2,000 stimuli, 20 Hz; left temporoparietal, 1,000 stimuli, 1 Hz; right temporoparietal, 1,000 stimuli, 1 Hz). Results were compared with a historical control group consisting of 29 patients who received left temporal stimulation (2,000 stimuli, 1 Hz). Both groups were treated on ten consecutive working days. Tinnitus severity was assessed at three time points: at baseline, after the last treatment session (day 12) and after a follow-up period of 90 days. A change of tinnitus severity over time was tested using repeated measures ANOVA with the between-subjects factor treatment group. Both groups improved similarly from baseline to day 12. However, there was a difference on day 90: the multisite stimulation group showed an overall improvement whereas patients receiving temporal stimulation returned to their baseline level of tinnitus severity. These pilot data suggest that multisite rTMS is superior to temporal rTMS and represents a promising strategy for enhancing treatment effects of rTMS in tinnitus. Future studies should explore this new protocol with respect to clinical and neurobiological effects in more detail.  相似文献   
110.
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