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993.
There is strong evidence indicating that inflammatory bowel disease (IBD) is increasing among black and minority ethnic (BME) communities. Despite this rise in prevalence, there is a paucity of research relating to ethnicity and IBD outside the USA. Furthermore, the symptoms of IBD are reported to start during childhood or adolescence in 20–25% of people with the condition. It is therefore important that young people's experiences of diagnosis, treatment and living with IBD are fully understood to ensure effective services and information provision. The study reported on in this paper was commissioned by a UK charity (Crohn's and Colitis UK) with the aim of increasing understanding of the specific issues and service needs of young people with IBD from BME communities. Empirical research entailed in‐depth semi‐structured interviews with 20 young people from BME groups accessed through gastroenterology departments at three collaborating NHS hospitals in England serving ethnically diverse populations. Interviews were carried out from June to December 2010 and sought to capture young people's views with IBD. A thematic analysis of their experiences identified many commonalities with other young people with IBD, such as the problematic route to formal diagnosis and the impact of IBD on education. The young people also experienced tensions between effective self‐management strategies and cultural norms and practices relating to food. Moreover, the ability of parents to provide support was hampered for some young people by the absence of culturally competent services that were responsive to the families’ communication needs. The findings highlight the need for more culturally appropriate information concerning IBD, and improved responsiveness to young people with IBD within primary care and the education system, as well as culturally competent messaging relating to the specific nature of the condition among the wider South Asian and black communities.  相似文献   
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995.
In the present study, we compared phenotypic differences in behavioral and neurophysiological responses to acute ethanol administration among six inbred rat strains. Genetic variation was found both for ataxia, as measured by loss of righting response (sleep time) after a hypnotic dose of ethanol, and for the depressant action of ethanol on the spontaneous discharge of cerebellar Purkinje neurons. Results from an analysis of covariance of these phenotypes, measured among the inbred strains, provided strong evidence for a high genetic correlation between sleep time and inhibition of cerebellar Purkinje neuron discharge in response to acute ethanol administration. However, ethanol metabolism was also found to correlate with the behavioral sensitivity of rats to ethanol. Preliminary data from the third generation of replicate lines of rats currently being selectively bred for high and low acute sensitivity to ethanol shows a trend toward divergence of both ethanol sleep time and neuronal sensitivity to acute ethanol. The conclusion from these data supports the hypothesis that the cerebellum is an important locus of ethanol action, and suggests that neuronal sensitivity to ethanol will continue to diverge between these rat lines as selection for the sleep time phenotype progresses.  相似文献   
996.
Bone marrow transplantation for Fanconi anemia   总被引:8,自引:6,他引:8  
Fanconi anemia is a genetic disorder associated with diverse congenital abnormalities, progressive bone marrow failure, and increased risk of leukemia and other cancers. Affected persons often die before 30 years of age. Bone marrow transplantation is an effective treatment, but there are few data regarding factors associated with transplant outcome. We analyzed outcomes of HLA-identical sibling (N = 151) or alternative related or unrelated donor (N = 48) bone marrow transplants for Fanconi anemia performed between 1978 and 1994 and reported to the International Bone Marrow Transplant Registry. Fanconi anemia was documented by cytogenetic studies in all cases. Patient, disease, and treatment factors associated with survival were determined using Cox proportional hazards regression. Two-year probabilities (95% confidence interval) of survival were 66% (58% to 73%) after HLA-identical siblings transplants and 29% (18% to 43%) after alternative donor transplants. Younger patient age (P .0001), higher pretransplant platelet counts (P = .04), use of antithymocyte globulin (P = .005), and use of low-dose (15 to 25 mg/kg) cyclophosphamide plus limited field irradiation (P = .009) for pretransplant conditioning and cyclosporine for graft-versus-host disease prophylaxis (P = .002) were associated with increased survival. Bone marrow transplants are effective therapy for Fanconi anemia. The adverse impact of increasing age and lower pretransplant platelet count on transplant outcome favors earlier intervention, especially when there is an HLA-identical sibling donor.  相似文献   
997.
Essential fatty acids (EFAs) are major structural components of the brain and through their effects on membrane properties can influence nerve conduction, transmitter release, and transmitter action. Prostaglandins (PGs) derived from EFAs have profound behavioral effects and are also able to modify conduction and transmitter function. Effects of alcohol on EFAs and PGs are therefore good candidates for explaining at least some of the actions of alcohol on brain function. Ethanol has three main known actions on EFA and PG metabolism: it reduces blood linoleic acid levels and induces or exaggerates EFA deficiency states; it blocks metabolism of linoleic acid to EFA metabolites which are known to be important in brain structure; and it enhances conversion of the linoleic acid metabolite, dihomo-gamma-linolenic acid, to PGE1. This review demonstrates that some of the short-term behavioral effects of ethanol and some of its long-term adverse effects on brain, liver, and other tissues may be partly explicable in terms of ethanol actions on EFA and PG metabolism. Modification of such metabolism by dietary and other means has already been shown to influence the effects of alcohol and alcohol withdrawal in both humans and animals. This promises to be a fruitful source of investigation with substantial implications for the understanding and treatment of alcoholism.  相似文献   
998.
During 24 weeks of hydroxyurea treatment, we monitored red blood cell (RBC) parameters in three patients with sickle cell disease, including F-cell and F-reticulocyte profiles, distributions of delay times for intracellular polymerization, sickle erythrocyte adherence to human umbilical vein endothelial cells in a laminar flow chamber, RBC phthalate density profiles, mean corpuscular hemoglobin concentration and cation content, reticulocyte mean corpuscular hemoglobin concentration, 1H-nuclear magnetic resonance transverse relaxation rates of packed RBCs, and plasma membrane lateral and rotational mobilities of band 3 and glycophorins. Hydroxyurea increases the fraction of cells with sufficiently long delay times to escape the microcirculation before polymerization begins. Furthermore, high pretreatment adherence to human umbilical vein endothelial cells of sickle RBCs decreased to normal after only 2 weeks of hydroxyurea treatment, preceding the increase in fetal hemoglobin levels. The lower adhesion of sickle RBCs to endothelium would facilitate escape from the microcirculation before polymerization begins. Hydroxyurea shifted several biochemical and biophysical parameters of sickle erythrocytes toward values observed with hemoglobin SC disease, suggesting that hydroxyurea moderates sickle cell disease toward the milder, but still clinically significant, hemoglobin SC disease. The 50% reduction in sickle crises documented in the Multicenter Study of Hydroxyurea in Sickle Cell Disease is consistent with this degree of erythrocyte improvement.  相似文献   
999.
Glial S-100 protein, soluble protein, and DNA were quantitatively studied in brains of gerbils chronically exposed to ethanol in a nutritionally complete fluid diet. Eight different brain areas were studied. After exposure to ethanol for 3 months followed by a 4-month post-treatment ethanol-free period, increased amounts of S-100 protein per wet weight were found in the frontal cerebral cortex, the sensory-motor cerebral cortex, the posterior cerebellar vermis, and the brainstem. The increase of S-100 in the posterior cerebellar vermis was paralleled by an increase in DNA per wet weight, which was also increased in the anterior cerebellar vermis. However, a decreased content of DNA was observed in the frontal cerebral cortex, despite the increase of S-100 protein, suggesting a cell loss affecting cells other than astroglial in this area. In the cerebellar vermis, elevated concentrations of soluble proteins per wet weight were found, whereas a decreased amount was found in the anterior cerebellar hemispheres. It is suggested that the S-100 protein acts as a marker for astroglial cell volume and that a concomitant increase of S-100 protein and DNA might indicate an increase in the number of astroglial cells. Thus, our results obtained after ethanol exposure and subsequent ethanol abstinence are compatible with changes consisting of astroglial hypertrophy in the cortex areas and brainstem, as well as astroglial hypertrophy and/or proliferation in the posterior cerebellar vermis, a clear sign of the preceding noxae.  相似文献   
1000.
Neutrophils incubated with 20 mM F- express a respiratory burst without degranulating or performing phagocytosis. After 60 min of F- treatment, the burst is exhausted and cannot be restarted. Neutrophils so treated have a microbicidal defect similar to that of chronic granulomatous disease (CGD): they kill Str. mitis at a nearly normal rate, but show a marked impairment in the destruction of S. aureus. They differ from CGD neutrophils in that they also display a defect in motility. This defect, however, is not so severe as to seriously impair their ability to kill bacteria by mechanisms that are independent of endogenously generated microbicidal oxidants.  相似文献   
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