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991.
Nuclear factor-kappaB: is it a therapeutic target for the adjuvant treatment of sepsis? 总被引:2,自引:0,他引:2
Fink MP 《Critical care medicine》2003,31(9):2400-2402
992.
Canuso R 《Journal of community health nursing》2003,20(1):37-49
This article describes 7 low-income mothers' experiences of attending a motivational event that combined peer and professional support in a baby-shower luncheon. The event provided a group context that reinforced health-enhancing messages presented by nurses and other professional staff in home visits. Important themes that emerged in qualitative analysis include reduction of isolation and promotion of bonding; information sharing and modeling to others; and enhancement of self-esteem. A discussion of how community health nurses can use these strategies in caring for pregnant women is presented. 相似文献
993.
Da Silva TR De Freitas JR Silva QC Figueira CP Roxo E Leão SC De Freitas LA Veras PS 《Infection and immunity》2002,70(10):5628-5634
The virulence of different isolates of Mycobacterium has been associated with two morphologically distinguishable colonial variants: opaque (SmOp) and transparent (SmTr). In this report we used an in vitro assay to compare macrophage (Mphi) responses to SmOp and SmTr Mycobacterium fortuitum variants, taking advantage of the fact that these variants were derived from the same isolate. Cells preactivated or not with gamma interferon (IFN-gamma) were infected with SmOp or SmTr M. fortuitum. We showed that SmOp and SmTr induced different levels of nitric oxide (NO) production by IFN-gamma-stimulated Mphi. Indeed, the amount of IFN-gamma-induced NO production by J774 cells was 4.8 to 9.0 times higher by SmOp (23.1 to 37.7 micro M) compared to SmTr infection (3.9 to 4.8 micro M) (P = 0.0332), indicating that virulent SmTr bacilli restricted NO production. In addition, IFN-gamma-induced NO production by Mphi was higher when correlated with reduction of only avirulent SmOp bacillus viability. SNAP (S-nitroso-N-acetyl-DL-penicillamine)-induced NO production did not modify SmTr viability, indicating its resistance to nitrogen radicals. Electron microscopy studies were performed to evaluate the capacity of phagosomes to fuse with lysosomes labeled with bovine serum albumin-colloidal gold particles. By 24 h postinfection, 69% more phagosome-containing SmOp variant had fused with lysosomes compared to the SmTr-induced phagosomes. In conclusion, these data indicate that virulent SmTr bacilli may escape host defense by restricting IFN-gamma-induced NO production, resisting nitrogen toxic radicals, and limiting phagosome fusion with lysosomes. 相似文献
994.
Role transition is never easy, but is complicated by the experienced neonatal nurse's frustration with reverting to a student role and becoming a novice practitioner, sometimes after years of developing a reputation as an expert nurse. This article discusses this transition, focusing on the skills needed to move successfully from nurse to nurse practitioner. Common to all advanced practice transitions are stages similar to those Benner identifies in her novice-to-expert theory of nursing practice. Feelings of frustration and inadequacy are common during the first year as an NNP. Studies focusing on role transition and role development suggest that a strong nursing identity is important for success in the NNP practice environment. Strategies to enhance the transition are discussed. 相似文献
995.
996.
Corbalán R Miñana MD Del Olmo JA Serra MA Rodrigo JM Felipo V 《Journal of molecular medicine (Berlin, Germany)》2002,80(2):117-123
Studies of animal models suggest that the activation of soluble guanylate cyclase by nitric oxide is altered in liver disease. We studied 77 patients with liver disease and 17 controls, to investigate whether the activation of soluble guanylate cyclase is altered in lymphocytes from patients with liver disease. The basal content of guanosine 3',5'-cyclic monophosphate (cGMP) in lymphocytes was decreased both in patients with liver cirrhosis (by 52%) and in patients with chronic hepatitis (by 62%). Activation of soluble guanylate cyclase by nitric oxide was higher in lymphocytes from patients with cirrhosis (3100+/-1000% of basal) or with hepatitis (5200+/-2500% of basal) than in lymphocytes from controls (1200+/-500% of basal). cGMP in plasma was increased in patients with liver disease. Successful (but not unsuccessful) treatment with interferon of patients with hepatitis due to virus C reversed all the above alterations. Altered modulation of soluble guanylate cyclase by nitric oxide in liver disease may play a role in the hemodynamic alterations found in these patients. 相似文献
997.
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1000.
Acid suppression therapy may not alter malignant progression in Barrett's metaplasia showing p53 protein accumulation 总被引:4,自引:0,他引:4
Carlson N Lechago J Richter J Sampliner RE Peterson L Santella RM Goldblum JR Falk GW Ertan A Younes M 《The American journal of gastroenterology》2002,97(6):1340-1345
OBJECTIVES: Several previous studies have shown that malignant progression in Barrett's metaplasia (BM) occurs even in patients treated with fundoplication or acid suppression therapy (AST). The aim of this study was to test the hypothesis that AST may not alter malignant progression in BM if key genes involved in DNA repair and cell cycle control, particularly p53, are defective. METHODS: Initial and follow-up biopsies from 21 patients with BM treated with AST and observed for 1-13 yr were entered in the study. All biopsies were graded for dysplasia and evaluated for p53 protein accumulation and oxidative DNA damage by immunohiostochemistry, using antibodies to p53 and to 8-hydroxydeoxyguanosine, respectively. DNA ploidy was determined using image analysis. Statistical analysis was performed using Kaplan-Meier curves, log rank test, and multivariate regression. RESULTS: Patients with p53 positive initial biopsies were more likely to have progression in dysplasia grade (p = 0.022) and DNA ploidy status (p = 0.023) than those with p53 negative biopsies. In eight patients AST resulted in significant reduction in oxidative DNA damage in the five patients with p53-negative initial biopsies, but not the three with p53 positive ones (p = 0.0007). CONCLUSIONS: We conclude that failure of AST to alter malignant progression in BM may be due, at least in part, to defects in DNA repair and cell cycle control resulting from p53 gene mutation, present before AST treatment. Although AST may be effective in preventing further DNA damage, it is unlikely to alter progression in genetically unstable cells. 相似文献