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91.
Antitumor activity of interleukin-12 against murine bladder cancer   总被引:5,自引:0,他引:5  
PURPOSE: We investigated the antitumor activity of interleukin-12 (IL-12) against MBT-2, a murine bladder carcinoma, to clarify whether or not IL-12 is effective against urothelial tumors. MATERIALS AND METHODS: MBT-2, a murine carcinogen-induced, poorly differentiated transitional cell carcinoma of C3H/He origin, was used. Three or 10 days after the subcutaneous administration of MBT-2 cells, C3H/He mice were injected intraperitoneally with IL-12 five times per wk. for 2 wk. Tumor growth was measured twice weekly. Spleen cells from the C3H/He mice that had rejected MBT-2 after the IL-12 treatment were examined for MBT-2-specific cytolytic T lymphocytes (CTL) activity and cytokine production. RESULTS: Tumor growth and acceptance was obviously suppressed when C3H/He mice were treated with IL-12 from 3 days after the tumor inoculation. In the spleen cells from the C3H/He mice that had rejected MBT-2, MBT-2-specific CTL activity and secretion of IL-2 and interferon (IFN)-gamma were clearly detected. However, the established MBT-2 tumor cells were not rejected when C3H/He mice were given IL-12 from 10 days after the tumor inoculation, although the tumor growth was transiently suppressed during the IL-12 treatment. CONCLUSION: These data demonstrate that IL-12 is considerably effective against murine bladder cancer and suggest the clinical application of IL-12 against human bladder cancer.  相似文献   
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AIM: The aim of the present study was to explore whether heme oxygenase-1 (HO-1) is involved in the hyperthermia-provided protection of the small intestine from ischemia/reperfusion injury in rats. METHODS: Intestinal damage was induced in male Sprague-Dawley rats by clamping both the superior mesenteric artery and the celiac trunk for 30 min, followed by reperfusion. Whole-body hyperthermia was induced in anesthetized rats by placement in a temperature-controlled water bath. Whole-body hyperthermia to a core temperature of 42-43 degrees C for 15 min was followed by passive cooling. We started the hyperthermic treatment 6 h before the vascular clamping. The severity of the mucosal injury was evaluated by several biochemical markers and histological findings. Hyperthermia-induced heat-shock proteins were detected by Western blotting. We also investigated the effect of zinc protoporphyrin IX (an HO-1 inhibitor) on the protective effect of hyperthermia. RESULTS: The rats, which were killed after ischemia/reperfusion, had severe intestinal inflammation. Hyperthermia significantly induced the production of Hsp70 and HO-1 in intestinal mucosa and significantly reduced ischemia/reperfusion-induced mucosal injury. The combination of zinc protoporphyrin IX with hyperthermia extinguished the protective effects of hyperthermia on ischemia/reperfusion injury. CONCLUSION: Hyperthermia protects against ischemia/reperfusion injury in rat small intestine through the expression of heat-shock proteins, especially HO-1.  相似文献   
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We performed a operation using a mini mid-line skin incision for ten-year-old male with funnel chest. The skin incision was made from the level of nipple to the lower end of the xiphoid process. He had sternal elevation as corrective surgery. There was no complication and he discharged at 11th day after surgery. We believe our method is more appropriate in fulfilling the cosmetic needs for the patient of funnel chest.  相似文献   
95.
The activities of Z-Phe-Arg-NMec(ZPA) hydrolase, cathepsin B and cathepsin H and the concentration of endogenous thiol protease inhibitor in fibroblasts from patients with galactosialidosis were found not to be significantly different from those in control fibroblasts. Culture for 5 days with thiol protease inhibitors such as leupeptin, E-64 or Z-Phe-Phe-CHN2 partially restored the beta-galactosidase activity of fibroblasts from patients, but did not affect the beta-galactosidase activity of fibroblasts from control subjects. However, culture with leupeptin, but not other protease inhibitors, increased the ZPA hydrolase and cathepsin B activities of fibroblasts from both patients and controls 2- to 4-fold. Sephadex G-75 chromatography showed that the activity of high molecular weight ZPA hydrolase, which was initially predominant in fibroblasts, decreased markedly during their culture with leupeptin, while the activities of lower molecular weight ZPA hydrolase and cathepsin B increased about 5-fold. These results suggest that high molecular weight ZPA hydrolase, which is presumably cathepsin J, degrades beta-galactosidase, and that the defect in galactosialidosis is impaired protection of beta-galactosidase from degradation.  相似文献   
96.
Background and PurposeAmyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease. Selective deficiency of edited adenosine deaminase acting on RNA 2 (ADAR2), a key molecule in the acquisition of Ca2+ resistance in motor neurons, has been reported in sporadic ALS (sALS) spinal motor neurons. Since ADAR2 activity is positively regulated by prolyl isomerase Protein never in mitosis gene A interacting-1 (Pin1), a known phosphorylation-dependent peptidyl-prolyl cis/trans isomerase, we investigated Pin1 expression in spinal motor neurons in sALS.MethodsSpecimens of the spinal cord were obtained from the lumbar region in eight sALS patients and age-matched five controls after postmortem examinations. The specimens were double stained with anti-Pin1 and anti-TAR DNA-binding protein of 43 kDa (TDP-43) antibodies, and examined under a fluorescence microscope.ResultsThis study analyzed 254 and 422 spinal motor neurons from 8 sALS patients and 5 control subjects, respectively. The frequency of motor neurons with high cytoplasmic Pin1 expression from the spinal cord did not differ significantly between sALS specimens without cytoplasmic TDP-43 inclusions and control specimens. However, in sALS specimens, neurons for which the Pin1 immunoluminescence intensity in the cytoplasm was at least twice that in the background were more common in specimens with cytoplasmic TDP-43 inclusions (p<0.05 in χ2 test).ConclusionsIn sALS, neurons with higher expression levels of Pin1 levels had more TDP-43 inclusions. Despite the feedback mechanism between Pin1 and ADAR2 being unclear, since Pin1 positively regulates ADAR2, our results suggest that higher Pin1 expression levels in motor neurons with TDP-43 pathology from sALS patients represent a compensatory mechanism.  相似文献   
97.
BACKGROUND: Neutrophil infiltration and lipid peroxide accumulation are involved in reperfusion-induced gastric mucosal injury in nitric oxide-depleted rats. AIM: To assess the effect of vitamin E on this injury. METHODS: After ischaemia-reperfusion, the total area of erosions, lipid peroxide contents in gastric mucosa, and gastric neutrophil accumulation were compared between nitric oxide-depleted rats with deficient, normal, and increased vitamin E intake over 8 weeks. Thiobarbituric acid-reactive substances and tissue-associated myeloperoxidase activity were measured in gastric mucosa as indices of lipid peroxidation and neutrophil infiltration. RESULTS: The total area of erosions was significantly increased in the vitamin E-deficient group compared with the sufficient-intake and vitamin-supplemented groups. Both thiobarbituric acid-reactive substances and myeloperoxidase activity also were significantly increased in the vitamin E-deficient group compared with others. The total area of erosions closely paralleled the increases in both thiobarbituric acid-reactive substances and myeloperoxidase activity. CONCLUSION: These results indicate that the inhibition of lipid peroxidation and interference with neutrophil infiltration by vitamin E may be responsible for its cytoprotective effect in ischaemia-reperfusion.  相似文献   
98.
Normal development of the stapes, especially the bilaminar structure of the footplate, in the mouse was investigated histologically. On day 14 of pregnancy, the footplate had an easily distinguishable lamina consisting of two layers. This bilaminar structure was seen clearly as a pale and loose portion composed of mesenchymal cells in the vestibular side adjacent to the original footplate in the stapedial ring. The authors considered this structure to be the same structure as the lamina stapedialis in the developing human stapes. A dualistic theory of the developmental origin of the footplate in the mouse is proposed.  相似文献   
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