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91.
The putative factor IX gene promoter in hemophilia B Leyden   总被引:11,自引:0,他引:11  
Hemophilia B Leyden is characterized by low levels of factor IX antigen and activity before the age of 15, whereas after puberty factor IX levels rise at a rate of about 5% per year. A single base substitution (-A----T) at position -20 was identified in the putative promoter of the gene cloned from a patient with hemophilia B Leyden. This nucleotide change was confirmed in a second patient from the same pedigree and was also found in a patient from a second Dutch pedigree with the same hemophilic phenotype. The results indicate that the two Dutch kindreds are related and point to the functional significance of the -20 position for the expression of the human factor IX gene.  相似文献   
92.
Gay  JC; Beckman  JK; Zaboy  KA; Lukens  JN 《Blood》1986,67(4):931-936
The role of platelet activating factor (PAF) as a regulator of human neutrophil superoxide (O2-) generation in response to soluble and particulate stimuli was examined. At concentrations greater than 10(-7) mol/L, PAF alone induced a brief burst of O2- production. When cells were exposed to PAF and either the chemotactic peptide n-formyl- methionyl-leucyl-phenylalanine (FMLP 10(-7) mol/L) or the tumor promoter phorbol myristate acetate (PMA 10 ng/mL), a marked synergistic augmentation of O2- release was noted when compared to control cells stimulated with FMLP or PMA alone. Mean percentage of enhancement by 10(-5) mol/L of PAF was 297% +/- 35% (n = 9) of control responses to FMLP and 185% +/- 16% (n = 3) of control responses to PMA. Consistent enhancement occurred with PAF concentrations of as low as 10(-9) mol/L. Enhancement could be demonstrated when neutrophils were exposed to PAF either at the same time as, or up to 60 minutes prior to, the second stimulus, and was neither reversed by removal of PAF from the medium prior to addition of FMLP or PMA nor dependent on the presence of extracellular divalent cations. Continuous recordings revealed that the enhancement was due to an increased maximal rate of O2- production. In contrast, PAF concentrations up to 10(-5) mol/L had only a minimal effect on the response to neutrophils to opsonized zymosan. Analysis of the enhancing properties of lipids structurally related to PAF revealed that the critical moiety was the saturated fatty acid at position 1. These results indicate the presence of a PAF-mediated positive feedback loop whereby the oxidative burst induced by some soluble stimuli is augmented. Modulation of neutrophil O2- production by PAF may serve to amplify neutrophil oxidative responses at sites of inflammation.  相似文献   
93.

Objectives

The European Association for the Study of the Liver (EASL) treatment recommendations for hepatitis C no longer discriminate between HIV/hepatitis C virus (HCV)‐coinfected and HCV‐monoinfected patients. However, recent data from Spain are questioning these recommendations on the basis of the findings of higher relapse rates and lower cure rates in HIV/HCV‐infected subjects. The aim of our study was to compare HCV cure rates in monoinfected and coinfected patients from Germany.

Methods

Data acquired from the Deutsches Hepatitis C‐Registry were analysed. A total of 5657 HCV‐monoinfected subjects and 488 HIV/HCV‐coinfected patients were included in the study. Rates of sustained virological response 12 weeks after the scheduled end of therapy (SVR12) were collected in both subgroups and in cirrhotic and noncirrhotic patients.

Results

HIV/HCV‐coinfected patients were more frequently male (84.6% vs. 56.4%, respectively; < 0.001) and younger than HCV‐monoinfected subjects (46.5 ± 9 vs. 53.8 ± 12.5 years, respectively; P < 0.001). The CD4 blood cell count was > 350 cells/μL in 63.1% of HIV‐positive subjects and 88.7% were on antiretroviral therapy. SVR12 rates were 90.3% (5111 of 5657) in our HCV‐monoinfected cohort and 91.2% (445 of 488) in our coinfected patients. Liver cirrhosis was confirmed in 1667 of 5657 (29.5%) monoinfected patients and 84 of 488 (17.2%; P < 0.001) coinfected patients. SVR12 rates did not differ between HCV‐monoinfected and HIV/HCV‐coinfected patients with liver cirrhosis (87.8% vs. 89.3%, respectively; = 0.864). A treatment duration of 8 weeks did not reduce the percentage of patients with SVR12 in either subgroup (93.7% in both groups).

Conclusions

We found high SVR12 rates in monoinfected as well as coinfected individuals. No differences were detected between the two subgroups regardless of whether there was accompanying liver cirrhosis or a shortened treatment duration.
  相似文献   
94.
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96.
We present the first analytical approach to demonstrate the in situ imaging of metabolites from formalin‐fixed, paraffin‐embedded (FFPE) human tissue samples. Using high‐resolution matrix‐assisted laser desorption/ionization Fourier‐transform ion cyclotron resonance mass spectrometry imaging (MALDI‐FT‐ICR MSI), we conducted a proof‐of‐principle experiment comparing metabolite measurements from FFPE and fresh frozen tissue sections, and found an overlap of 72% amongst 1700 m/z species. In particular, we observed conservation of biomedically relevant information at the metabolite level in FFPE tissues. In biomedical applications, we analysed tissues from 350 different cancer patients and were able to discriminate between normal and tumour tissues, and different tumours from the same organ, and found an independent prognostic factor for patient survival. This study demonstrates the ability to measure metabolites in FFPE tissues using MALDI‐FT‐ICR MSI, which can then be assigned to histology and clinical parameters. Our approach is a major technical, histochemical, and clinicopathological advance that highlights the potential for investigating diseases in archived FFPE tissues. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
97.

Purpose

Volumetric assessment of the liver regularly yields discrepant results between pre- and intraoperatively determined volumes. Nevertheless, the main factor responsible for this discrepancy remains still unclear. The aim of this study was to systematically determine the difference between in vivo CT-volumetry and ex vivo volumetry in a pig animal model.

Material and Methods

Eleven pigs were studied. Liver density assessment, CT-volumetry and water displacement volumetry was performed after surgical removal of the complete liver. Known possible errors of volume determination like resection or segmentation borders were eliminated in this model. Regression analysis was performed and differences between CT-volumetry and water displacement determined.

Results

Median liver density was 1.07 g/ml. Regression analysis showed a high correlation of r2 = 0.985 between CT-volumetry and water displacement. CTvolumetry was found to be 13% higher than water displacement volumetry (p < 0.0001).

Conclusion

In this study the only relevant factor leading to the difference between in vivo CT-volumetry and ex vivo water displacement volumetry seems to be blood perfusion of the liver. The systematic difference of 13 percent has to be taken in account when dealing with those measures.  相似文献   
98.

Objective

This study was performed to investigate the impact of HAART versus no HAART and nucleoside free versus nucleoside containing HAART on the efficacy and safety of pegylated interferon and ribavirin therapy for the treatment of chronic HCV infection in HIV/HCV co-infected patients. In addition a control group of HCV mono-infected patients undergoing anti-HCV therapy was evaluated.

Methods

Multicenter, partially randomized, controlled clinical trial. HIV-negative and -positive patients with chronic HCV infection were treated with pegylated interferon alfa-2a and ribavirin (800 - 1200 mg/day) for 24 - 48 weeks in one of four treatment arms: HIV-negative (A), HIV-positive without HAART (B) and HIV-positive on HAART (C). Patients within arm C were randomized to receive open label either a nucleoside containing (C1) or a nucleoside free HAART (C2).

Results

168 patients were available for analysis. By intent-to-treat analysis similar sustained virological response rates (SVR, negative HCV-RNA 24 weeks after the end of therapy) were observed comparing HIV-negative and -positive patients (54% vs. 54%, p = 1.000). Among HIV-positive patients SVR rates were similar between patients off and on HAART (57% vs. 52%, p = 0.708). Higher SVR rates were observed in patients on a nucleoside free HAART compared to patients on a nucleoside containing HAART, though confounding could not be ruled out and in the intent-to-treat analysis the difference was not statistically significant (64% vs. 46%, p = 0.209).

Conclusions

Similar response rates for HCV therapy can be achieved in HIV-positive and -negative patients. Patients on nucleoside free HAART reached at least equal rates of sustained virological response compared to patients on standard HAART.  相似文献   
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100.
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