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101.
This review describe the effect of manganese on the heart and blood vessels. The interaction between manganese and redox systems and manganese contribution to atherosclerosis development were also investigated. The results of the experimental studies on animals, on isolated blood vessels in vitro and on people professionally exposed to manganese were presented.  相似文献   
102.
Abnormalities in monoamine neurotransmission have been implicated in the pathogenesis of alcoholism, mood disorders and schizophrenia. Murine norepinephrine transporter gene (NET) has been mapped to a region on chromosome 8 where a quantitative trait locus for ethanol sensitivity. Therefore we tested whether norepinephrine transporter (NET) gene variants confer susceptibility to either alcohol dependence or severe alcohol withdrawal symptoms. There is a highly polymorphic silent G1287A mutation in the NET gene. In our study 157 alcoholics and 185 healthy unrelated matched control subjects were analyzed for a silent G1287A mutation. No significant differences in allele and genotype distribution between control subjects f(A)=0.33 and alcoholics f(A)=0.29 were found. No significant results were found in more homogenous subgroups, i.e. alcoholics with severe alcohol withdrawal (seizures, delirium), early onset age<26 nor dependent patients with positive familial history of alcoholism. These results suggest that the NET gene polymorphism in exon 9 accession number: mRNA: NM_001043, genomic contig.: NT_019610, is unlikely to be involved in the susceptibility to alcoholism and severe alcohol withdrawal.  相似文献   
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Rehabilitation by sport is of importance in regard to champions and also to the every-day life of ill and crippled people.

The value of sport, on the one hand, as a part of the rehabilitation of amputees and, on the other hand, in satisfying the need for movement in the blind has been repeatedly demonstrated. However, thorough study is required to improve training methods and to enable the disabled to practice the particular sport events.

Skiing is of special importance in the rehabilitation of disabled people.

In 1956 the first ski courses for amputees were organized in Poland and showed that those who had undergone a limb amputation are able to practice this event in rehabilitation.

  相似文献   
106.
BACKGROUND: Increasing evidence points to the role of the extracellular Calcium Sensing Receptor (CaSR) as a multimodal receptor responding to diverse physiologic stimuli, such as extracellular divalent and polyvalent cations, amino acids, and ionic strength. Within the kidney, these stimuli converge on the CaSR to coordinate systemic calcium and water homeostasis. In this process, the impact of urinary pH changes on the activity of the CaSR has not yet been defined. We therefore performed the present study to analyze the pH sensitivity of the CaSR. METHODS: To assess the activation state of the CaSR, we developed a new method based on the functional coupling between CaSR activity and gating of calcium sensitive potassium currents mediated by SK4 potassium channels. Two-electrode voltage clamping was used to determine whole cell currents in Xenopus oocytes heterologously expressing rat CaSR and rat SK4 potassium channels. RESULTS: Coexpression of CaSR and SK4 gave rise to potassium currents that were dependent on CaSR-mediated intracellular calcium release, and thereby corresponded to the activation state of the CaSR. In presence of extracellular calcium, ambient alkalinization above pH 7.5 increased CaSR activity. Evaluation of the CaSR calcium sensitivity at various ambient proton concentrations revealed that this effect was due to a sensitization of the CaSR towards extracellular calcium. CONCLUSION: Coexpression with SK4 potassium channels provides a fast and sensitive approach to evaluate CaSR activity in Xenopus oocytes. As disclosed by this novel technique, CaSR activity is regulated by extracellular pH.  相似文献   
107.
This study focuses on glutathione (GSH) level in red blood cells, as well as on glutathione peroxidases (GSH-Px) activities in red blood cells and in plasma of chronic renal failure (CRF) patients following renal transplantation. We want to focus our main attention on plasma GSH-Px, the selenoenzyme that is synthesized primarily in the kidney. In CRF patients, activity of this enzyme is significantly reduced, and the reduction decreases with the progress of the disease, reaching in the end-stage 20% to 30% of the activity of healthy patients. We have shown that following renal transplantation the activity of plasma GSH-Px is restored very rapidly, and 2 weeks after surgery it reached the value of the control group. Red blood cell GSH level is significantly higher in CRF patients, and following transplantation, no significant changes were observed. Red blood cell GSH-Px activity before transplantation was the same as in healthy patients and did not change significantly after surgery.  相似文献   
108.
Exposure to fuel from cooking and heating has not been studied in Europe, where lung cancer rates are high and many residents have had a long tradition of burning coal and unprocessed biomass. Study subjects included 2,861 cases and 3,118 controls recruited during 1998-2002 in the Czech Republic, Hungary, Poland, Romania, Russia, Slovakia, and the United Kingdom. The odds ratio of lung cancer associated with solid fuel use was 1.22 (95% confidence interval (CI): 1.04, 1.44) for cooking or heating, 1.37 (95% CI: 0.90, 2.09) for solid fuel only for cooking, and 1.24 (95% CI: 1.05, 1.47) for solid fuels used for both cooking and heating. Risk increased relative to the percentage of time that solid fuel was used for cooking (p(trend) < 0.0001), while no risk increase was detected for solid fuel used for heating. The odds ratio of lung cancer in whole-life users of solid cooking fuel was 1.80 (95% CI: 1.35, 2.40). Switching to nonsolid fuels resulted in a decrease in risk. The odds ratio for the longest duration of time since switching was 0.76 (95% CI: 0.63, 0.92). The data suggest a modest increased risk of lung cancer related to solid-fuel use for cooking rather than heating.  相似文献   
109.
It is important for the prevention of DNA changes caused by environment to understand the biological consequences of DNA damages and their molecular modes of action that lead to repair or alterations of the genetic material. Numerous genotoxicity assay systems have been developed to identify DNA reactive compounds. The available data show that plant bioassays are important tests in the detection of genotoxic contamination in the environment and the establishment of controlling systems. Plant system can detect a wide range of genetic damage, including gene mutations and chromosome aberrations. Recently introduced molecular cytogenetic methods allow analysis of genotoxicity, both at the chromosomal and DNA level. FISH gives a new possibility of the detection and analysis of chromosomal rearrangements in a great detail. DNA fragmentation can be estimated using the TUNEL test and the single cell gel electrophoresis (Comet assay).  相似文献   
110.
Synthetic antitumor anthracenedione drugs, in contrast to anthracycline antibiotics, are ineffective in free radical formation in NADH dehydrogenase system. Our results have indicated that neither the reduction potential nor the side chain conformation and the energies of border orbitals (HOMO and LUMO) determine the ability of anthracenediones to stimulate reactive oxygen species formation in NADH dehydrogenase system. It was shown that the distribution of the molecular electrostatic potential (MEP), around the quinone system was crucial for this ability. We have found for non-stimulating anthracenediones that the clouds of positive MEP cover the quinone carbon atoms while for agents effective in stimulating reactive oxygen species formation the clouds of negative MEP cover continuously the aromatic core together with the quinone system.  相似文献   
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