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Blood flow directions of the portal trunk, splenic vein, and superior mesenteric vein were studied using an ultrasonic Doppler duplex system in 146 healthy adults, 132 patients with liver cirrhosis, 76 with hepatocellular carcinoma, 32 with idiopathic portal hypertension, 134 with chronic hepatitis, 18 with acute hepatitis, and 142 with other diseases. Spontaneous hepatofugal flow in one or more of the three vessels examined was detected in 14 patients. Spontaneous hepatofugal flow in the portal trunk was detected in three patients with liver cirrhosis. In two of these three patients, the hepatofugal flow in the portal trunk disappeared after medication. This is interesting, since hepatofugal flow may, in fact, be more common than we suspected in patients who, because of the severity of their disease, are not able to undergo invasive examination. Postoperative hepatofugal flow in the portal system was detected in 20 of 71 cases: 15/17 patients after interposition mesocaval shunting, 2/17 after distal splenorenal shunting, 2/31 after splenectomy, and 1/6 after splenic artery occlusion with steel coils. In more than half the cases of interposition mesocaval shunting (9/17 patients), blood flow in the portal trunk was hepatofugal. However, hepatopetal blood flow in the portal trunk was maintained in most cases of distal splenorenal shunting (13/17), showing the merits of this technique as a selective portosystemic shunt operation.  相似文献   
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The development of accurate, minimally invasive continuous glucose monitoring (CGM) devices has been the subject of much work by several groups, as it is believed that a less invasive and more user-friendly device will result in greater adoption of CGM by persons with insulin-dependent diabetes. This article presents the results of preliminary clinical studies in subjects with diabetes of a novel prototype microneedle-based continuous glucose monitor. In this device, an array of tiny hollow microneedles is applied into the epidermis from where glucose in interstitial fluid (ISF) is transported via passive diffusion to an amperometric glucose sensor external to the body. Comparison of 1396 paired device glucose measurements and fingerstick blood glucose readings for up to 72-hour wear in 10 diabetic subjects shows the device to be accurate and well tolerated by the subjects. Overall mean absolute relative difference (MARD) is 15% with 98.4% of paired points in the A+B region of the Clarke error grid. The prototype device has demonstrated clinically accurate glucose readings over 72 hours, the first time a microneedle-based device has achieved such performance.  相似文献   
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The reliability of a loop-mediated isothermal amplification (LAMP) method for the detection of human herpesvirus 8 (HHV-8) DNA was evaluated. Although LAMP products were produced with the DNA sample extracted from BCP-1 cells, LAMP products were not produced with the DNAs from seven other human herpesviruses. The detection limit of the HHV-8 LAMP method was 100 copies of target sequence/tube. To determine whether the HHV-8 LAMP method could be used to quantify viral DNA, threshold times, which are defined as the time (in s) it takes to reach the threshold turbidity level (0.1), were measured for the amplification of serial dilutions of a DNA plasmid containing the target sequence. The standard curve possessed a correlation coefficient of 0.9428 with a slope of -84.079 and y-intercept value of 1936.2. Additionally, an attempt was made to detect viral DNA in 17 specimens collected from Kaposi's sarcomas and two cell lines obtained from primary effusion lymphomas. HHV-8 DNA was detected in 14 of the 17 Kaposi's sarcoma tissue samples and both of the primary effusion lymphoma cell lines. Viral DNA was not detected in HHV-8 LAMP-negative samples using the real-time PCR method.  相似文献   
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Background/Objectives: Identifying reliable pretreatment imaging biomarkers for pancreatic neuroendocrine neoplasm (PanNEN) is a key imperative. Extracellular volume (ECV) fraction quantified with equilibrium contrast-enhanced CT can be easily integrated into routine examinations. This study aimed to determine whether ECV fraction with equilibrium contrast-enhanced computed tomography (CECT) could predict long-term outcomes in patients with PanNEN.MethodsThis study was a retrospective observational study of 80 patients pathologically diagnosed with PanNEN at a single institution. ECV fraction of the primary lesion was calculated using region-of-interest measurement within PanNEN and the aorta on unenhanced and equilibrium CECT. The impact of clinical factors and tumor ECV fraction on progression-free survival (PFS) and overall survival (OS) was assessed with univariate and multivariate analyses using Cox proportional hazards models. The correlation between WHO classification and tumor ECV fraction was evaluated using Kendall rank correlation coefficients.ResultsPFS and OS rates were estimated as 93.4% and 94.6%, 78.7% and 86.2%, 78.7% and 77.0%, and 78.7% and 66.6% at 1, 3, 5, and 10 years, respectively. Multivariate analysis revealed that Union for International Cancer Control (UICC) stage (hazard ratio [HR] = 3.95, P = 0.003), WHO classification (HR = 12.27, P = 0.003), and tumor ECV fraction (HR = 11.93, P = 0.039) were independent predictors of PFS. Patient age (HR = 1.11, P < 0.001), UICC stage (HR = 3.14, P = 0.001), and tumor ECV fraction (HR = 5.27, P = 0.024) were independent significant variables for predicting OS. Tumor ECV fraction had a weak inverse relationship with WHO classification (P = 0.045, τ = ?0.178).ConclusionsECV fraction determined by equilibrium CECT and UICC stage may predict survival in patients with PanNEN.  相似文献   
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Costimulation of T cells by B7-H2, a B7-like molecule that binds ICOS   总被引:23,自引:1,他引:23       下载免费PDF全文
Wang S  Zhu G  Chapoval AI  Dong H  Tamada K  Ni J  Chen L 《Blood》2000,96(8):2808-2813
This report describes a new human B7-like gene designated B7-H2. Cell surface expression of B7-H2 protein is detected in monocyte-derived immature dendritic cells. Soluble B7-H2 and immunoglobulin (Ig) fusion protein, B7-H2Ig, binds activated but not resting T cells and the binding is abrogated by inducible costimulator Ig (ICOSIg), but not CTLA4Ig. In addition, ICOSIg stains Chinese hamster ovary cells transfected with B7-H2 gene. By suboptimal cross-linking of CD3, costimulation of T-cell proliferation by B7-H2Ig is dose-dependent and correlates with secretion of interleukin (IL)-2, whereas optimal CD3 ligation preferentially stimulates IL-10 production. The results indicate that B7-H2 is a putative ligand for the ICOS T-cell molecule. (Blood. 2000;96:2808-2813)  相似文献   
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Cholangiographic findings of early-stage extrahepatic bile duct carcinoma   总被引:1,自引:0,他引:1  
BACKGROUND: To clarify the cholangiographic findings of early-stage (T1, tumor confined to the mucosal or fibromuscular layer) extrahepatic bile duct carcinoma. METHODS: Cholangiographic images were retrospectively analyzed without other information in 55 patients with extrahepatic bile duct carcinoma who underwent surgical treatment. Tumor stages were T1 (n = 10). T2 (n = 17), and T3 (n = 28). Cholangiographic findings were classified as "diffuse sclerosis," "stenosis," "papillary polypoid filling defect," or "nodular polypoid filling defect". "Papillary polypoid filling defect" was the term used when the width of the base was smaller than the width of the polypoid filling defect. RESULTS: T1 patients showed papillary polypoid filling defects (n = 8) or nodular polypoid filling defects (n = 2) on cholangiography. When cholangiography showed papillary polypoid filling defects, 8 of the 14 resected patients showed T1 stage tumor histologically. CONCLUSIONS: In this study, 57% (8/14) of resected patients with papillary polypoid filling defects showed T1 stage tumor. No T1 stage tumor showed stenosis or diffuse sclerosis.  相似文献   
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