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41.
Hepatitis B virus (HBV) recurrence after liver transplantation is significantly reduced by prophylaxis with hepatitis B immune globulins (HBIG) or antiviral drugs in nonreplicating patients and by the combination of both drugs in replicating patients. However, the load of HBV DNA, which defines replicating status in patients undergoing liver transplantation, remains unclear. This study analyzes the correlation between the viral load, tested with a single amplified assay, at the time of liver transplantation, and the risk of hepatitis B recurrence in 177 HBV carriers who underwent transplantation in a single center from 1990 to 2002. Overall, HBV relapsed after surgery in 15 patients (8.5%) with a 5- and 8-year actuarial rate of recurrence of 8% and 21%, respectively. After liver transplantation hepatitis B recurred in 9% of 98 selected subjects treated only with immune globulins and in 8% of 79 viremic patients who received immune globulins and lamivudine (P = NS). A linear correlation was observed between recurrence and viral load at the time of surgery. In transplant patients with HBV DNA higher than 100,000 copies/mL, 200-99,999 copies/mL, and DNA undetectable by amplified assay, hepatitis B recurred in 50%, 7.5%, and 0% of patients, respectively. Overall, a viral load higher than 100,000 copies/mL at the time of liver transplantation was significantly associated with hepatitis B recurrence (P = .0003). In conclusion, spontaneous or antiviral-induced HBV DNA viral load at the time of surgery classifies the risk of HBV recurrence after liver transplantation and indicates the best prophylaxis strategy.  相似文献   
42.
Sir, We are writing to provide some clarifications on the EditorialComment by Drüeke et al. [1]. We would have been happyto provide these very same clarifications had we been fairlyinvited to do so before the publication of the article. First of all, we would like to  相似文献   
43.
Endoscopic treatment of benign tumors of the nose and paranasal sinuses.   总被引:1,自引:0,他引:1  
OBJECTIVE: The endoscopic approach can be successfully employed for the treatment of benign tumors such as fibroosseus and vascular lesions, pleomorphic adenomas, gliomas, and schwannomas. STUDY DESIGN AND SETTING: Nineteen patients diagnosed with benign tumors of the nasal cavity and paranasal sinuses and treated using an endoscopic approach were retrospectively reviewed. The endoscopic approach was used exclusively in 15 cases and was associated with an external approach in 4 cases (due to an intracranial extension of the tumor in 3 patients and its location at the level of the anterior wall of the frontal sinus in the last case). RESULTS: The resection of the lesions was radical in 18 patients and subtotal in 1 case. The mean follow-up was 27 months and only 1 recurrence (5%) was observed in the juvenile angiofibroma group 20 months postoperatively. CONCLUSION: and significance In selected cases, endoscopic surgery can be considered an effective treatment for the resection of benign tumors involving the sinonasal tract.  相似文献   
44.
Right isomerism is characterized by the combination of an obstructed pulmonary outflow tract and a total anomalous pulmonary venous connection (TAPVC), which is obstructed in nearly half of the patients. Fourteen patients less than 2 years of age with right isomerism have been seen in our unit. Thirteen of them underwent palliation consisting of a systemic-pulmonary shunt (10 patients) or a combination of shunt and TAPVC repair (3). There were 7 hospital deaths (54%). The presence of obstructed pulmonary venous drainage was the major risk factor in the surgical treatment of these complex cardiac anomalies (p less than .02). Guidelines for the palliative management of right isomerism are suggested.  相似文献   
45.
46.
Calcitonin (CT) secretion following stimulation was studied in 9 young women suffering from spasmophilia, this having been diagnosed by clinical and electromyographic criteria. The controls were 9 women, matched by age, who responded negatively to the diagnostic tests. After rapid intravenous infusion (60 sec) of 4 mg/kg/lean body mass of calcium (as gluconate), CT concentration increased measurably (p less than 0.0001) in the controls, while remaining unchanged in the spasmophilic. The average increase per cent vs. the baseline values was 225% in the controls and 34% in those with spasmophilia (p less than 0.005). 5 out of 9 of the patients showed a completely flat curve. This finding, due to a diminished CT reserve in spasmophilia, may be considered a possible diagnostic feature as well as a fundamental pathological element in the reduction of the intracellular calcium pool responsible for the neuromuscular hyperexcitability. Moreover, the therapeutic use of the hormone in this condition is to be encouraged.  相似文献   
47.
48.
Endovascular repair for concomitant multilevel aortic disease.   总被引:2,自引:0,他引:2  
OBJECTIVE: Patients with multilevel aortic disease represent a small subgroup with the need for extensive surgical treatment at considerable risk. We present our experience of endovascular exclusion for simultaneous thoracic and abdominal aortic disease in four patients. METHODS: Between January 2002 and January 2005, four patients underwent endovascular repair for simultaneous thoracic and abdominal aortic disease. Mean age was 69+/-10 years (range, 60-81). Thoracic lesions included penetrating aortic ulcer (n=2, ruptured=1), atherosclerotic aneurysm (n=1), and chronic type B dissection (n=1). Abdominal aortic disease included atherosclerotic infrarenal (n=3) and juxtarenal (n=1) aortic aneurysms. Thoracic aortic stent-grafts had been the following: Excluder/TAG (n=3) or Talent (n=1) straight tube devices. Abdominal aortic stent-grafts used were as following: Excluder (n=3) or Zenith (n=1). All patients were followed-up with CT-angiography and chest X-rays 1, 4, 12 months after the procedure, and once per year thereafter. RESULTS: Stent-graft deployment was technically successful in all cases. Intraoperative mortality was not observed. Mean procedure time was 94+/-34 min (range, 70-145). Early postoperative complications occurred in one patient that developed acute renal failure but dialysis was not required. Mean hospitalisation was 8+/-5 days (range, 4-15). Late death occurred in one patient for an undetected ruptured thoracic type 1 endoleak. All three survivors are currently well 16.5 months (range, 3-36) after surgery. No neurological complications developed. CONCLUSION: Simultaneous abdominal and thoracic endovascular repair for multilevel aortic disease is feasible and could be a viable alternative in high-risk patients, who otherwise may not be suitable candidates for conventional repair.  相似文献   
49.
Objective: Increased dimension of the aortic root and proximal aorta is considered a significant risk factor for catastrophic events that involve the ascending aorta. The objective of this study was to determine the possible correlation between pre-dissection aortic diameter and the occurrence of Stanford type A aortic dissection. Methods: Samples of dissected ascending aortas were obtained from 220 patients at the time of their operation. Two groups were identified: patients with connective tissue disorders (Group 1, n = 94) and those without (Group 2, n = 126). Measurements of the true (intimal) lumen were conducted and extrapolated as reliable approximation of pre-dissection aortic diameter. The possible association of intimal diameter with anthropometric and demographic data was analyzed. Results: Median aortic diameter was, respectively, 41.8 and 41.3 mm for patients with and without connective tissue disorders (41.4 mm for the entire cohort). Data analysis indicated that 57% of patients had aortic diameter above 40 mm, while patients with frank aneurysm accounted only for 10%; this proportion was higher in Group 1 compared to Group 2 (17.2% vs 4.7%). Poor or no correlation was demonstrated between aortic size and any of the anthropometric or demographic variables essayed. Significant subgroup differences were found among patients with a history of cigarette smoking, hypertension, diabetes, chronic renal insufficiency, and bicuspid aortic valve. Conclusion: Although aortic diameter remains a strong indication for preventive surgery in patients with inherited connective tissue disorders, acute aortic dissection occurs rarely in the setting of true ascending aortic aneurysms, and despite normal or near-normal aortic size in more than one-third of subjects. Dissection superimposing on small aortic diameters can be regarded as an expression of substantial functional tissue susceptibility to aortic catastrophic events.  相似文献   
50.
Although observational studies suggest that hyperhomocysteinemia may be a risk factor for coronary allograft vasculopathy (CAV), prospective data on homocysteine-lowering interventions and CAV development are lacking. We, therefore, randomized 44 de novo heart transplant (HT) recipients to 15 mg/day of 5-methyl-tetrahydrofolate (n=22), or standard therapy (control group, n=22) to investigate the effect of homocysteine lowering on the change in coronary intimal hyperplasia during the first 12 months after transplant, as detected by intra-vascular ultrasound (IVUS). Although 12 months after HT, homocysteinemia was lower in folate-treated patients (p<0.001), coronary intimal area increased similarly in the two groups (p>0.4). Conversely, hypercholesterolemia and cytomegalovirus infection were both associated with increased intimal hyperplasia (p<0.04), independently from folate intake. Sub-group analysis revealed that folate therapy reduced intimal hyperplasia in patients with hyperhomocysteinemia before randomization (n=19; p=0.02), but increased intimal hyperplasia in patients with normal homocysteine plasma concentrations (p=0.02). This bimodal effect of folate therapy persisted significantly after adjusting for cytomegalovirus infection and hypercholesterolemia. Despite effective in prevent hyperhomocysteinemia after heart transplantation, folate therapy does not seem to affect early CAV onset. However, sub-group analysis suggests that folate therapy may delay CAV development only in patients with baseline hyperhomocysteinemia, while may favor CAV progression in recipients with normal baseline homocysteinemia.  相似文献   
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