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861.
862.
The effects of amiloride on basal and hormone-stimulated protein phosphorylation were studied in isolated rat hepatocytes labeled with 32P-phosphate. Two types of effect on basal phosphorylation were detected: 1. an increase in labeling of two proteins with molecular weights 93,000 and 18,000; 2. a decrease in labeling of proteins with molecular weights 46,000, 34,000, 22,000 and 13,000. All these effects were dose-dependent (maximum with 0,8-to 1 mM) and reached a maximum after 30 to 40 min treatment of the cells with the drug. Amiloride inhibited specifically all insulin effects whereas glucagon specific effects were largely unaffected. In pulse-chase experiments, amiloride increased and insulin decreased the rate of dephosphorylation of the same proteins (Mr 46,000, 34,000 and 22,000). The data support the conclusion that in hepatocytes insulin increases the degree of phosphorylation of proteins by inhibiting an amiloride-sensitive phosphatase.  相似文献   
863.
Although alveolar echinococcosis (AE) can cause a serious disease with high mortality and morbidity similar to malign neoplasms. A 62-year-old woman admitted to a hospital located in Sivas, Turkey, with the complaints of fatigue and right upper abdominal pain. On contrast abdominal CT, a 54×70×45 mm sized cystic lesion was detected in the left lobe of the liver that was seen to extend to the posterior mediastinum and invade the diaphragm, esophagus, and pericardium. The cystic lesion was seen to be occluding the inferior vena cava and left hepatic vein at the level where the hepatic veins poured into the inferior vena cava. Bilateral pleural effusion was also detected. We discussed this secondary Budd-Chiari Syndrome (BCS) case, resulting from the AE occlusion of the left hepatic vein and inferior vena cava, in light of the information in literature.  相似文献   
864.
Gallic acid, a polyphenyl class natural product from gallnut and green tea, is known to be antioxidant, anti‐inflammatory and radical scavenger. In this study, we aimed to investigate the possible protective effects of gallic acid on paraoxonase and arylesterase activities in liver exposed to acute alcohol intoxication. Paraoxonase and arylesterase activities in liver tissue and serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were measured. Histological investigations were also made. In our study, we observed a significant increase of serum alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, which are indicators of liver damage after acute ethanol consumption. Gallic acid therapy has significantly reduced the increase in these biomarkers, indicating a possible hepatoprotective effect of gallic acid. Ethanol consumption caused a significant decrease in liver paraoxonase activity (P < 0.001). Gallic acid treatment partly restored this decreased paraoxonase activity, which resulted from ethanol administration. A gallic acid dose of 100 mg/kg was observed as highest restoring effect for paraoxonase activity (P < 0.05). The activity of arylesterase was decreased in the ethanol group as compared with the control group, but this was not significant. However, 50 mg/kg of gallic acid treatment restored the loss of this activity due to ethanol exposure (P < 0.001). We observed that gallic acid ameliorates the liver damage caused by excessive alcohol consumption in a dose‐dependent way. Our results in this study showed that gallic acid might have a protective effect against alcoholic liver disease. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
865.
Hakan Isik 《Science activities》2018,55(3-4):149-155
Lab activities have been innovated and progressed to fulfill the purpose that students need to experience physics concepts through hands-on and minds-on interactions. However, student-centered and conceptual activities in physics labs are challenged with time and material constraints that degrades the merits of the learning environment. This study adopts a pedagogical design, “learning by preparing to teach”, to address the challenges with conducting a satisfactory number of activities in physics labs and therefore promoting student hands-on and minds-on experiences with the activities. Eight activities covering the conceptual variables of thermal conduction in a two-hour lab session were studied by freshmen students at a university. To implement the pedagogical design, the students were arranged into the learning and teaching groups that paved way to a lab design that student was first learners and then teachers. Lab activities were configured that each group studied a certain set of activities. Upon completing the activities, members of the learning groups were designated to the teaching groups in which students cooperated to achieve conceptual objectives of the lab. The results showed that a usual lab duration becomes effective to cover numerous activities.  相似文献   
866.
867.
Biological Trace Element Research - Ischemia/reperfusion (I/R) injury is associated with a strong inflammatory and oxidative stress response to hypoxia and reperfusion that impair organ function....  相似文献   
868.
Temporal variations in the endothelium-dependent relaxant effects of acetylcholine (ACh) in mice and histamine (HA) in rat thoracic aorta have been studied. The relaxations induced by higher concentrations of ACh and HA were significantly dependent on the time the tissues were obtained. However, neither EC 50 (the concentration inducing half of the maximum response) values for ACh and HA, nor K B (antagonist dissociation constant) values for atropine and diphenhydramine were found to be statistically significant depending upon the time of obtaining aorta preparations. These results show that the in vitro responsiveness of mice and rat thoracic aortas to endothelium-dependent relaxant effects of ACh and HA, respectively, changes over a 24-h period. These variations might be dependent on a temporal rhythm in post-receptor events, i.e., guanylate cyclase-cGMP-phosphodiesterase system which mediates responses to endothelium-derived relaxing factor(s).  相似文献   
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