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91.
To evaluate the usefulness of FDG-PET as a predictor of prognosis, 34 patients with untreated malignant lymphoma in the head and neck region were studied. After FDG-PET and treatment, they were observed from 15 to 50 months. Tumors which were aggressive and resistant to treatment tended to show high uptake of FDG. The survival rate of patients with high uptake of FDG, DAR > 8, was lower than the rate of the other patients. It is considered to be useful to add FDG uptake of the tumor to other prognostic factors for predicting the prognosis.  相似文献   
92.
BACKGROUND: After chemotherapy for metastatic testicular tumors, masses may remain, often in the metastatic sites. This study analyses the role of resections for the residual masses. METHODS: Seventy-seven patients with advanced (stage II, III) testicular tumors were treated. Of these, 38 patients, including eight with seminoma and 30 patients with non-seminomatous germ cell tumors, underwent resection of residual masses after chemotherapy and have been followed for a median of 41.5 months (range 2-138) after the resection. RESULTS: Residual masses were necrosis/fibrosis in 19 patients, mature teratoma in 11 and cancer in eight. The ratio of cancer in stage III (41.2%) was significantly higher than that in stage II (4.8%). Ten of 38 (26.3%) patients experienced recurrences in sites other than the resected sites, and five of 10 patients have died of cancer. Most recurrences (80%) occurred within two years. Recurrences after resection were detected in 4.8% of stage II patients, 52.9% of stage III, 16.7% of necrosis/fibrosis and mature teratoma, and 62.5% of cancer. The survival rate of patients with cancer was significantly lower in spite of adjuvant chemotherapy after surgery. CONCLUSIONS: Resection for residual masses after chemotherapy in metastatic testicular tumors was useful in confirming the tissue and in controlling the metastatic sites. Recurrences were often found in patients with cancer in the residual mass and the prognosis of patients with cancer was poor, therefore the development of more effective therapy for patients with cancer is required to improve the prognosis.  相似文献   
93.
Renal excreted angiotensin converting enzyme (ACE) inhibitor captopril, and renal.hepatic bile excreted ACE inhibitor temocapril, were compared by monitoring serum ACE and renal ACE expression (protein and mRNA) in streptozotocin-induced diabetic rats. Serum ACE levels did not change in untreated diabetic rats or in those treated with temocapril, compared with normal control rats. However, serum ACE levels significantly increased in diabetic rats treated with captopril after 3 months (153.8 +/- 23.0 vs. 43.5 +/- 5.5 IU/l/37 degrees C, p < 0.01) and 6 months (113.6 +/- 9.3 vs. 36.9 +/- 2.9 IU/l/37 degrees C, p < 0.01) compared with normal control rats. Compared with normal control rats (3.6 +/- 0.4), proximal tubular ACE protein expression significantly (p < 0.01) decreased in untreated diabetic rats (1.6 +/- 1.1), but significantly (p < 0.01) increased in diabetic rats treated with captopril (3.7 +/- 0.3) and temocapril (3.5 +/- 0.4). Renal ACE mRNA levels decreased in untreated diabetic rats (125.5 +/- 20.3 vs. 313.3 +/- 53.4, p < 0.01) compared with normal control rats for 6 months. Renal ACE mRNA levels tended to increase in diabetic rats treated with captopril (184.4 +/- 51.2 vs. 125.5 +/- 20.3) and temocapril (165.4 +/- 43.2 vs. 125.5 +/- 20.3) compared with untreated diabetic rats for 6 months. In conclusion, diabetic rats had lower proximal tubular ACE protein expression and lower renal ACE mRNA levels compared with normal control rats. Furthermore, both ACE inhibitors increased renal ACE protein and mRNA expression, but differed in their effect on serum ACE levels.  相似文献   
94.
A 59-year-old man with a history of the thoraco-abdominal esophagus resection with retrosternal gastric tube reconstruction for esophageal cancer complicated by anastomosis leakage and purulent pericarditis was admitted for aortic regurgitation due to infective endocarditis. Floppy vegetation and worsening cardiac failure indicated aortic valve replacement. In a median sternotomy approach, the thickest adhesion between the cervical esophagus and posterior surface of the manubrium sternae was freed using an ultrasonic osteotome. Severe adhesions in the pericardium due to purulent pericarditis were found. Median sternotomy enabled minimal exposure of the aortic root, upper right atrium, and right superior pulmonary vein for instituting extracorporeal circulation and replacing the aortic valve. The patient’s postoperative course was uneventful. For cardiac surgery in patients with a retrosternal gastric tube, left anterior or right thoracotomy may be considered to avoid gastric tube injury. Median sternotomy, however, is an alternative enabling safe heart exposure, and the ultrasonic osteotome was very useful in incising the sternum without injuring the cervical esophagus, which had no serosa.  相似文献   
95.
Roles of CD4+ and CD8+ T cells in discordant skin xenograft rejection   总被引:8,自引:0,他引:8  
An essential role of murine CD4+ T cells in immune reactivity and skin graft rejection in discordant xenogeneic combinations have been reported. Our study was conducted to further clarify the roles of CD4+ and CD8+ T cells in discordant skin xenograft rejection, by using CD4 and CD8 knockout [C57BL/6 Cr Slc (B6; H-2b) background] mice. When human skins were grafted on CD8 knockout mice or B6 mice, both hosts rejected human skin grafts within 12 days after grafting. By contrast, survival of human skin grafts was significantly prolonged in CD4 knockout mice (mean survival times=19.3+/-(SD) 1.6 days; median 19 days). Fully allogeneic C3H/He Slc (H-2k) skin grafts were rejected within 14 days in CD4 knockout mice, suggesting that non-CD4+ T cells in CD4 knockout mice were immunocompetent for allograft rejection. In spleens of these recipient mice, CD8+ T cells seemed to be activated 10 days after human skin grafting. Immunohistological analysis revealed the infiltration of CD8+ T cells at the site of transplanted human skin on CD4 knockout mice. To further examine the role of CD8+ T cells in CD4 knockout mice, human skin grafting was performed on day 0 followed by administration of anti-CD8 monoclonal antibody on days 0, 5, and 14. The administration of anti-CD8 monoclonal antibodies caused the significant prolongation of human skin graft survival. These results indicate the following two conclusions: (1) CD4+ T cells have an essential role in rejecting discordant human skin xenografts rapidly and (2) however, CD8+ T cells also are capable of rejecting discordant human skin xenografts.  相似文献   
96.
Purpose: To evaluate the effects of bare stents and covered stents on the aortic wall, especially the vasa vasorum. Methods: Eight bare stents and nine covered stents were placed in the infrarenal aorta of nine dogs. The dogs were euthanized at 4–45 weeks after stent placement. The vasa vasorum was evaluated by microstereoscopy with vascular casting, and the histopathology of the aortic wall was examined by light microscopy. Results: In the unstented normal aorta, vasa vasorum nourished the adventitia and the outer media, and the intima and inner media were avascular. In the stented segment, vascular dilatation and proliferation of vasa vasorum, medial atrophy, and intimal hyperplasia were observed, more prominent for covered stents than for bare stents. Conclusion: Intravascular stent placement caused not only medial atrophy and intimal hyperplasia but also proliferation of the vasa vasorum, probably due to hypoxia in the aortic wall. Received: 0/00/00/Accepted: 0/00/00  相似文献   
97.
Rigor mortis is an important phenomenon to estimate the postmortem interval in forensic medicine. Rigor mortis is affected by temperature. We measured stiffness of rat muscles using a liquid paraffin model to monitor the mechanical aspects of rigor mortis at five temperatures (37, 25, 10, 5 and 0 °C). At 37, 25 and 10 °C, the progression of stiffness was slower in cooler conditions. At 5 and 0 °C, the muscle stiffness increased immediately after the muscles were soaked in cooled liquid paraffin and then muscles gradually became rigid without going through a relaxed state. This phenomenon suggests that it is important to be careful when estimating the postmortem interval in cold seasons.  相似文献   
98.
An 80-year-old asymptomatic man presented with ST-segment elevation in leads V1 to V5. Coronary CT angiography showed that microfistulae arising from multiple arteries may have led to myocardial infarction from intracoronary thromboembolism within the dilated left anterior descending (LAD).  相似文献   
99.
In August 1997, a 68-year-old man presented with right pelvic pain. Pelvic computed tomography (CT) and bone scintigraphy showed a huge tumor of the right iliac bone. No other lesion was detected, in spite of a high serum carcinoembryonic antigen level (CEA, 963ng/ml). In October 1997, the iliac bone tumor was widely resected, and thereafter was diagnosed to be a metastatic adenocarcinoma of unknown origin. After a resection, the serum CEA level dropped as low as 6.4ng/ml, but gradually went up to 80ng/ml in October 1999. Next, a lung tumor in the left upper lobe was detected by routine chest CT. In January 2000, a left upper lobectomy was performed, and based on not only the pathological findings but also on an immunohistochemical analysis for napsin A expression, the tumor was diagnosed to be lung adenocarcinoma. The histological and immunohistochemical findings in the previously resected bone lesion were completely compatible with those in the pulmonary tumor, which was finally regarded as M1 lung cancer. In October 2002, the patient was alive without any symptoms, although the serum CEA level was elevated again. We consider this case worthy of presentation because of its unique clinical course as well as the successful long-term survival after surgical treatment alone, for both the primary and metastatic lesions.  相似文献   
100.
MR imaging in idiopathic portal hypertension   总被引:2,自引:0,他引:2  
Magnetic resonance imaging was performed in four patients with biopsy proven idiopathic portal hypertension (IPH). The MR images show proximity of medium-sized intrahepatic vessels to each other and to the liver surface in all patients. Small vessels running parallel to the second order branches of the intrahepatic portal vein are commonly seen as collateral pathways of portal flow in IPH and were seen in two patients. These findings were clearly demonstrated on gradient-recalled echo images. Intrahepatic periportal abnormal high intensity was seen in all patients on T2-weighted images and may reflect abnormalities in the portal tracts such as fibrous enlargement and increase in the number of vascular channels. Tiny low-intensity nodules sometimes observed in liver cirrhosis were not seen in any patient. Magnetic resonance was a useful noninvasive method in the differentiation of IPH from liver cirrhosis.  相似文献   
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