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Aging is a normal physiological process involving changes in the respiratory system, thereby causing an increased incidence of pulmonary infections such as hospital-acquired pneumonia (HAP). The primary aim of this study was to investigate the role of acute-phase reactants and inflammation-based biomarkers in predicting 90-day mortality in patients aged over 65 years who were hospitalized in the intensive care unit (ICU) due to HAP. Clinical records of patients aged ≥65 years who were diagnosed as having HAP and were followed up in ICU were retrospectively evaluated. One hundred and fifteen ICU patients (67.8% male, mean age 76.81 ± 7.480 years) were studied. Ninety-day mortality occurred in 43 (37.4%) patients. Red cell distribution (RDW, %), mean platelet volume (MPV, f/L), white blood cell count (WBC, 103/μL), C-reactive protein (CRP, mg/L), and procalcitonin (PCT, ng/mL) median values were 18.2 (13.7–35.6), 7.42 (5.66–11.2), 14.3 (3.21–40), 9.58 (0.12–32), 0.41 (0.05–100) in the group with 90-day mortality. In the Receiver Operator Characteristics Curve analysis, a WBC value 18.2 × 10ˆ3/μL predicted 90-day independent mortality with a sensitivity of 90.70% and specificity of 31.94% (P = .029). The results indicated that serum WBC level can be used for predicting long-term mortality and prognosis in HAP patients aged over 65 years. High WBC value was statistically significant in predicting 90-day independent mortality (P < .05). 相似文献
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Left ventricular (LV) apical thrombus formation is a well described and clinically important complication of acute myocardial infarction (MI) with a substantial risk of thromboembolism. Alterations in the inflammatory status may contribute to this complication. The aim of this study was to evaluate the predictive role of the systemic immune-inflammation index (SII) in identifying high risk patients who will develop an apical thrombus formation during the acute phase of anterior transmural infarction. Consecutive 1753 patients (mean age: 61.5 ± 9.6 years; male: 63.8 %) with first acute anterior MI who underwent primary percutaneous coronary intervention were assessed. Patients were divided into 2 groups according to the presence of apical thrombus. SII was calculated using the following equation: neutrophil (N) × platelet (P) ÷ lymphocyte (L). LV apical thrombus was detected on transthoracic echocardiogram in 99 patients (5.6%). Patients with an apical thrombus had lower LV ejection fraction, prolonged time from symptoms to treatment, higher rate of post-percutaneous coronary intervention thrombolysis in myocardial infarction flow ≤1 and significantly higher mean high-sensitivity C-reactive protein, and SII values and lower lymphocyte than those without an apical thrombus. Admission SII level was found to be a significant predictor for early LV apical thrombus formation complicating a first-ever anterior MI. This simple calculated tool may be used to identify high-risk patients for LV thrombus and individualization of targeted therapy. 相似文献
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In vivo depletion of CD11c+ dendritic cells abrogates priming of CD8+ T cells by exogenous cell-associated antigens 总被引:21,自引:0,他引:21
Jung S Unutmaz D Wong P Sano G De los Santos K Sparwasser T Wu S Vuthoori S Ko K Zavala F Pamer EG Littman DR Lang RA 《Immunity》2002,17(2):211-220
Cytotoxic T lymphocytes (CTL) respond to antigenic peptides presented on MHC class I molecules. On most cells, these peptides are exclusively of endogenous, cytosolic origin. Bone marrow-derived antigen-presenting cells, however, harbor a unique pathway for MHC I presentation of exogenous antigens. This mechanism permits cross-presentation of pathogen-infected cells and the priming of CTL responses against intracellular microbial infections. Here, we report a novel diphtheria toxin-based system that allows the inducible, short-term ablation of dendritic cells (DC) in vivo. We show that in vivo DC are required to cross-prime CTL precursors. Our results thus define a unique in vivo role of DC, i.e., the sensitization of the immune system for cell-associated antigens. DC-depleted mice fail to mount CTL responses to infection with the intracellular bacterium Listeria monocytogenes and the rodent malaria parasite Plasmodium yoelii. 相似文献
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Gullu H Erdogan D Caliskan M Tok D Yildirim E Ulus T Turan Sezgin A Muderrisoglu H 《Echocardiography (Mount Kisco, N.Y.)》2006,23(10):835-842
BACKGROUND: In this study, we searched for a correlation between transthoracic coronary flow reserve (CFR) and well-established surrogates of coronary atherosclerosis. METHODS: The study was conducted on 136 healthy subjects (mean age: 39.9 +/- 7.3 years) who were free of coronary risk factors. Transthoracic echocardiography was used to measure the aortic stiffness index (AoSI), aortic distensibility (AoD), and aortic elastic modulus (AoEM). High-resolution ultrasound was used to measure brachial artery endothelium-dependent and independent vasomotion and carotid intima-media thickness (IMT). In addition, transthoracic second harmonic Doppler echocardiography was used to measure CFR. RESULTS: All of the parameters significantly correlated with each other except brachial endothelium-independent dilation. CFR correlated significantly with brachial endothelium-dependent dilation (EDD) (r = 0.302, P < 0.01), carotid IMT (r =-0.388, P < 0.01), brachial artery diameter (r = 0.340, P < 0.01), AoD (r = 0.275, P < 0.01), AoS (r =-0.299, P < 0.01), and AoEM (r =-0.30,7 P < 0.01). Carotid IMT correlated significantly with brachial EDD and modestly with brachial artery diameter, AoD, AoS, and AoEM.In multivariate analysis, carotid IMT (beta=-0.323, P < 0.0001) and brachial artery diameter (beta = -0.259, P = 0.001) were significant independent predictors of CFR. The left ventricular mass index (beta= 0.371, P < 0.0001), brachial EDD (beta = -0.232, P = 0.002), and CFR (beta = -0.228, P = 0.003) were significant predictors for IMT. CONCLUSION: Transthoracic CFR correlated significantly with well-established noninvasive predictors of atherosclerosis, and we suggest that it can be used as a surrogate for coronary atherosclerosis. 相似文献