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91.
PURPOSE: Primary non-Hodgkin's lymphoma (LY) and anaplastic carcinoma (AC) of the thyroid gland are rare malignant tumors, and the initial symptoms of these diseases are very similar. The aim of our study was to compare the characteristics of the two diseases using computed tomographic (CT) scans in order to make an accurate differential diagnosis. MATERIALS AND METHODS: Ten patients with LY and 10 with AC were analyzed. Differences in the CT findings of the two diseases were evaluated before treatment and statistically tested with either Student's t-test or the chi-square test. RESULTS: In the analysis of characteristics of CT imaging, the existence of calcification and necrosis, and heterogeneous tumor were dominant findings in AC, and there was a statistically significant difference in frequency between the two diseases (p < 0.01). Calcification detected in AC was usually multiple and/or gross (mean size: phi8.2 mm). All lymphadenopathies were delineated as having the same homogeneous attenuation as the tumors in the thyroid gland in LY, but were shown as irregular rim enhancement in AC. CONCLUSION: The CT features of the two diseases are characteristic in terms of calcification, necrosis, and tumor composition. Evaluation by means of CT imaging is useful in distinguishing between LY and AC.  相似文献   
92.
We report a family in which the father had central core disease and his son had congenital neuromuscular disease with uniform type 1 fibers. This is the first report of such a combination. Although they had no recognized mutation in the ryanodine receptor gene, it is highly likely that the son also had central core disease but without core structures. The absence of cores may be due to the muscle sample or the young age of the patient since core structures have been reported to increase with age. Although the prevalence of core structures in individual muscles is unknown, there is a possibility of sampling error. In some patients, congenital neuromuscular disease with uniform type 1 fibers is closely related to or identical with central core disease.  相似文献   
93.
Tissue plasminogen activator (tPA) has been used to treat acute thrombotic lesions. Roles other than the activation of fibrinolytic pathways have been suggested for tPA in the mature brain. We used the in situ hybridization technique to investigate the changes in tPA mRNA expression within the brain after cortical ablation. We found that expression of tPA mRNA started to increase diffusely in the cortex ipsilateral to the injury 6 h after ablation. This increase had become prominent 24 h after ablation. On d 5, the expression of tPA mRNA had returned to that of the control animals except for the area near the injury. We also found that administration of MK-801 before injury suppressed the increase of tPA mRNA in the ipsilateral cortex. These results suggest that the increase in tPA mRNA is likely to be mediated via activation of NMDA receptors.  相似文献   
94.
95.
Background: Pediatricians use corticosteroids for prolonged periods of time for the treatment of many diseases, including rheumatic disease. The side-effects of corticosteroids, especially cataracts, are widely recognized, but the predictive risk factors for steroid-induced cataracts have not yet been fully characterized.
Methods: The relationship between the formation of cataracts and steroid therapy was evaluated in patients with rheumatic disease.
Results: The initiation of steroid therapy in children under 12 years of age ( P  = 0.041) and i.v. methylprednisone pulse therapy (IVMP) ( P  = 0.046) are significant risk factors for inducing cataracts. In contrast, the cumulative corticosteroid dose, sex, and daily corticosteroid dose were not associated with cataract formation.
Conclusions: Younger children, who need frequent IVMP to treat their rheumatic diseases, should be examined by ophthalmologists frequently to avoid developing amblyopia from cataracts.  相似文献   
96.
A young Japanese man developed localized trichorrhexis nodosa (LTN) of the scalp hair in the winter season. To investigate the roles of shampoo, severe sunlight exposure and/or mechanical injuries, we performed the following studies. Hair was collected from the patient and from a control. The study was performed in two steps. In the first step, hair was put into shampoo, rinsed with saline water, and then exposed to ultraviolet B (UVB) radiation once a day for one week. In the second step, the hair was similarly treated, but each shaft was bent gently with forceps before UVB exposure. Scanning electron microscopic studies revealed cuticular changes when the hair was treated only with shampoo and UVB. When it was treated with shampoo, UVB, and mechanical bending, the patient's hair developed longitudinal and transverse fractures of the hair shafts, while the control hair showed only partial damage to the hair shaft. On the basis on the above findings, we conclude that mechanical bending may damage the hair shaft.  相似文献   
97.
In this study, detection rates of Leishmania parasites from human skin were compared among three different types of specimens, formalin-fixed, ethanol-fixed, and frozen, by polymerase chain reaction (PCR) and Southern blotting. For this purpose, we used biopsy specimens collected from 19 leishmaniasis patients and performed PCR and Southern hybridization with the probe specific for Leishmania (Viannia) braziliensis complex. Among these 19, 16 specimens were from cutaneous leishmaniasis (CL), one, diffuse cutaneous leishmaniasis (DCL) and 2, mucocutaneous leishmaniasis (MCL) and were formalin-fixed and paraffin-embedded. The causative agents for one case of CL and one case of DCL were already identified as L. (Leishmania) complex. Six specimens of CL were preserved in 100% ethanol. Two specimens of MCL were frozen tissues. PCR using the formalin-fixed and paraffin-embedded specimens revealed positive bands at 70bp in 9 (47.4%) out of 19 specimens of CL, MCL and DCL. Southern blotting detected the signals in 12 (63.2%) out of the 19. PCR using the 100% ethanol-fixed specimens revealed positive bands in 4 (66.7%) out of 6, and Southern blotting also detected the signals in 4 (66.7%) out of the 6. PCR and Southern blotting using 2 frozen specimens of MCL were always positive (100%). Although we failed to detect significant differences by Chi-square test between the results from the formalin-fixed, paraffin-embedded specimens and those from 100% ethanol-fixed ones, we concluded that ethanol-fixed specimens, convenient for transportation and storage, would be more useful for diagnosis of leishmaniasis by PCR in a developing country.  相似文献   
98.
99.
Summary Light and electron microscopic study and morphometric analysis were performed on the spinal cords and roots from six cases of acute Werdnig-Hoffmann disease and four control cases, in search of the pathogenesis of the selective motor neuron changes considered primarily responsible for Werdnig-Hoffmann disease. This investigation posits a centrifugal traction mechanism based upon the discovery of cylindrical outgrowths of glial bundles, selective loss of large myelinated fibers, and axonal degeneration in the proximal portion of anterior spinal roots (and to a lesser extent in posterior spinal roots) in all six disease cases. This traction mechanism exerts principally upon anterior spinal nerve roots and can account for morphologic and morphometric data characteristically ascribed to Werdnig-Hoffmann disease.This investigation was done during the tenure of a Research Fellowship of the Muscular Dystrophy Associations of America  相似文献   
100.
BACKGROUND: Scopolamine butylbromide (hyoscine-N-butylbromide, HB) is an anticholinergic drug used as a smooth muscle relaxant, and is used even in some surgical procedures during general anesthesia. HB also causes an increase in heart rate as a side effect. The authors evaluated the efficacy of esmolol on hemodynamic changes induced by HB in major abdominal surgery under inhalation anesthesia. METHODS: Seventeen patients for major abdominal surgery were randomly assigned to control group (C group, n = 9) or to esmolol group (E group, n = 8). Anesthesia was induced with propofol and was maintained with isoflurane-nitrous oxide inhalation and intermittent administration of fentanyl and vecuronium. At the time of bowel anastomosis, 20 mg of HB was administrated as an antispasmodic. In E group, esmolol 0.6 mg x kg(-1) was administered immediately after HB administration. RESULTS: There were no differences in the patient background between the two groups. At 1 to 10 minutes after HB administration, heart rate increased significantly compared with that at pre-administration in C group, while there was no significant change in heart rate in E group. Heart rate in E group was significantly lower than that in C group at 2 and 3 minutes after HB administration. Blood pressure was not significantly changed in both groups during the observation period. CONCLUSIONS: The simultaneous administration of HB and esmolol was useful for heart rate control after HB administration.  相似文献   
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