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This report describes a 65-year-old woman who developed granulomatous lesions consistent with sarcoidosis during etanercept therapy for rheumatoid arthritis. Hilar and mediastinal lymphadenopathy and multiple nodules in both lung fields developed 21 months after administration of etanercept. Noncaseating epithelioid cell granulomas consistent with sarcoidosis were detected in a lung biopsy specimen and in the parietal pleura obtained via thoracotomy. Diseases showing similar histologic changes were excluded, and a diagnosis of sarcoidosis was made. Etanercept was discontinued, which resulted in symptomatic relief, improvement of oxygenation and radiologic findings. There is substantial evidence of tumor necrosis factor-alpha involvement in the induction and maintenance of granuloma formation; however, we should keep in mind that granulomatous disease, such as sarcoidosis, can develop during treatment with a tumor necrosis factor-alpha blocking agent, such as etanercept.  相似文献   
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OBJECTIVE: Chronic Chlamydia pneumoniae infection has been identified serologically in patients with COPD. The aim of this study was to examine whether the severity of emphysema is related to elevated antibody titres against C. pneumoniae. METHODOLOGY: We measured antibody titres against C. pneumoniae using ELISA, and assessed the severity of emphysema by the percentage of low attenuation area (%LAA) using high resolution (HR) CT in patients with COPD and in non-smoking control subjects. RESULTS: The mean %LAA was 2.2% in non-smoking controls (n = 28) and 13.3% in COPD patients (n = 94). COPD patients with a high IgG antibody index to C. pneumoniae (> or =2.0, n = 42) had a significantly higher %LAA (16.8%) than those with a low IgG index (<2.0, n = 52) (10.6%, P = 0.01). In addition, COPD patients with a high IgA antibody index (> or =2.0, n = 46) had a significantly higher %LAA (15.9%) than those with a low IgA index (<2.0, n = 48) (10.9%, P = 0.048). COPD patients with a high IgA antibody index also had a significantly lower %DLco than that associated with a low IgA index (68.1% and 80.3%, respectively, P = 0.007). There were no significant differences in age, smoking index or FEV(1)/FVC between these groups. CONCLUSION: These results suggest that high antibody titres against C. pneumoniae are linked with the severity of emphysema on high resolution CT and decreased diffusing capacity to carbon monoxide.  相似文献   
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Ceftriaxone‐associated biliary pseudolithiasis is common among children; however, there are only a few reports of pseudolithiasis in adult patients on HD. This retrospective cohort study included 278 adult patients on ceftriaxone therapy from 1 February 2016 to 1 September 2018. Pseudolithiasis was defined as a new development of sludge or stones in the gallbladder within 60 days of ceftriaxone therapy. After excluding patients with preexisting gallstones and a history of cholecystectomy, 113 patients on maintenance HD, and another 98 patients were enrolled as the HD and control group, respectively. Thirteen patients developed pseudolithiasis. Its incidence was significantly higher in the HD group than that in the control group. Multivariate logistic regression analyses showed that development of pseudolithiasis was significantly associated with HD and ceftriaxone dose. Therefore, HD in patients receiving ceftriaxone therapy appears to be associated with a risk of pseudolithiasis. These findings highlight the need for careful follow‐up.  相似文献   
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Hypertensive rat arteries exhibited severe medial smooth muscle cell injury and necrosis. Electron microscopic observations showed the smooth muscle cells of these arteries exhibited characteristics of focal cytoplasmic necrosis forming new cytodemarcating membrane between the healthy cytoplasm and necrotic cytoplasm. When the focal necrotic cytoplasm disappeared from the injured smooth muscle cells, it left it with a moth-eaten leaf-like appearance (moth-eaten necrosis). At an advanced stage of injury, smooth muscle cells changed to islet-like cell bodies with newly formed basement membranes around them, and further islet-like cell bodies and cell debris disappeared leaving lamellar and reticular basement membranes.In hypertensive rats injected with nitroblue tetrazolium (NBT), formazan deposits were observed in the medial cells and nitrotyrosine, a biomarker of peroxynitrite, were immunohistochemically observed in the arterial media. Nick-end positive extranuclear small granular bodies, which might have derived from focal necrotic cytoplasm and nucleus, were detected in the arterial media using DNA nick-end labeling method. Based on electron microscopical and histochemical findings, we conjectured that the focal cytoplasmic necrosis of the smooth muscle cells in the arterial media depended on injury arising from mitochondria-derived oxidants.  相似文献   
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Background: Oxidative stress is believed to play a crucial role in aging and age‐related diseases, and is widely thought to increase morbidity and mortality in the elderly. Assessment of biomarkers of oxidative stress, such as 8‐isoprostane and 8‐hydroxy‐2‐deoxyguanosine, are considered to be useful in predicting disease risks at the population level. Objective: The aim of the present study was to assess the health status of the elderly by comparing their lifestyles and levels of oxidative stress biomarkers. Methods: We carried out a cross‐sectional study where urine samples from a total of 100 elderly men and women were assayed for 8‐isoprostane, 8‐hydroxy‐2‐deoxyguanosine, selenium, cadmium and creatinine. They were asked to answer a questionnaire that included questions about their lifestyle. Results: Most of the participants were prehypertensive, non‐alcohol users and on a rich plant‐based diet. There were no differences in any biomarkers of oxidative stress between men and women. 8‐Isoprostane was found to correlate positively with systolic blood pressure in women, but not in men. There was a slight increase of 8‐isoprostane in participants with a poor intake of vegetables, and a decrease of 8‐hydroxy‐2‐deoxyguanosine in participants who consumed fish. Multiple regression analysis showed that oxidative stress biomarkers were positively associated with cadmium, and negatively associated with selenium and fish intake in all participants, 89% of which were non‐smokers. Conclusion: Results from the present study show that fish intake has the potential of decreasing oxidative stress among elderly persons. Geriatr Gerontol Int 2012; 12: 547–554.  相似文献   
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We investigated the effects of stress‐shielding on both viscoelastic properties and microstructure of collagen fibers in the Achilles tendon by proton double‐quantum filtered (1H‐DQF) NMR spectroscopy. The right hind‐limbs of 20 Japanese white rabbits were immobilized for 4 weeks in a cast with the ankle in plantarflexion. Dynamic viscoelasticity of the Achilles tendons was measured using a viscoelastic spectrometer. Proton DQF NMR signals were analyzed to determine the residual dipolar coupling of bound water molecules in the Achilles tendons. Both the dynamic storage modulus (E′) and dynamic loss modulus (E″) decreased significantly in the Achilles tendons of the stress‐shielding group. The results of the 1H‐DQF NMR examination demonstrated significantly reduced residual dipolar coupling in the Achilles tendons of this same group. The disorientation of collagen fibers by stress‐shielding should contribute to degradation of the dynamic storage and loss moduli. The alterations of the collagen fiber orientation that contributed to the function of tendinous tissue can be evaluated by performing an analysis of 1H DQF NMR spectroscopy. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1708–1712, 2013  相似文献   
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