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31.
The mechanisms of tumor metastasis to the sentinel lymph nodes are poorly understood. Vascular endothelial growth factor (VEGF)-A plays a principle role in tumor progression and angiogenesis; however, its role in tumor-associated lymphangiogenesis and lymphatic metastasis has remained unclear. We created transgenic mice that overexpress VEGF-A and green fluorescent protein specifically in the skin, and subjected them to a standard chemically-induced skin carcinogenesis regimen. We found that VEGF-A not only strongly promotes multistep skin carcinogenesis, but also induces active proliferation of VEGF receptor-2-expressing tumor-associated lymphatic vessels as well as tumor metastasis to the sentinel and distant lymph nodes. The lymphangiogenic activity of VEGF-A-expressing tumor cells was maintained within metastasis-containing lymph nodes. The most surprising finding of our study was that even before metastasizing, VEGF-A-overexpressing primary tumors induced sentinel lymph node lymphangiogenesis. This suggests that primary tumors might begin preparing their future metastatic site by producing lymphangiogenic factors that mediate their efficient transport to sentinel lymph nodes. This newly identified mechanism of inducing lymph node lymphangiogenesis likely contributes to tumor metastasis, and therefore, represents a new therapeutic target for advanced cancer and/or for the prevention of metastasis.  相似文献   
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33.

Purpose

Occlusal trauma, resulting in the destruction of alveolar bone, is a form of periodontal disease caused by excessive mechanical stress (MS) during hyperocclusion. Previously, we showed that CC chemokine ligand (CCL) 2/CCR2 receptor axis plays a crucial role in MS-dependent osteoclastogenesis. However, in the previous work, we were unable to precisely measure changes in alveolar bone profiles. In the present study, we sought to establish a precise method for evaluating alveolar bone resorption induced by hyperocclusion using micro-computed tomography.

Methods

Under anesthesia, a stainless steel wire was attached to the molars of 5-week-old C57/BL6 wild-type (WT) mice, CCL2?/? mice, and CCR2?/?mice to induce occlusal force overload. At days 0 and 7, hard tissue samples were harvested and analyzed by micro-computed tomography.

Results

In the WT mice, bone mineral density of the alveolar bone was significantly decreased at day 7 as compared with day 0, with marked alveolar bone resorption observed. Similarly, significant alveolar bone resorption was observed in the CCL2?/? and CCR2?/? mice at day 7 as compared with day 0.

Conclusions

Micro-computed tomographic images can be used to measure changes in bone mineral density in a mouse model of hyperocclusion. This method may be useful for further investigating bone changes in other periodontal disease research fields.  相似文献   
34.

Purpose

To evaluate 18F-fluorodeoxyglucose (FDG) uptake to predict the malignant nature and analyze the correlation between FDG uptake and expression of glucose transporter 1 (Glut-1) and hexokinase II (HK-II) in thymic epithelial tumors.

Materials and methods

Eleven patients with a thymic epithelial tumor who underwent FDG PET/CT before therapy were reviewed. The thymic tumors were classified by the WHO histological classification and Masaoka clinical staging. Comparison of maximum standardized uptake value (SUVmax) of the lesion was made between the low-risk (Type A, AB and B1) and high-risk {Type B2, B3 and C (thymic cancer)} groups and among clinical stages. Expression of Glut-1 and HK-II was analyzed immunohistochemically.

Results

All 11 tumors showed FDG uptake visually. SUVmax was significantly higher in the high-risk group (n = 5, 5.24 ± 2.44) than the low-risk group (n = 6, 3.05 ± 0.55) (P = 0.008). Staining scores of both Glut-1 and HK-II were significantly higher in the high-risk group than in the low-risk group (Glut1: P = 0.034 and HK-II: P = 0.036). There were no significant differences in SUVmax (P = 0.11), Glut-1 (P = 0.35) and HK-II scores (P = 0.29) among clinical stages. SUVmax was significantly correlated to each of the staining scores of Glut-1 (ρ = 0.68, P = 0.031) and HK-II (ρ = 0.72, P = 0.024).

Conclusion

These preliminary results support the previously published view that SUVmax may be useful to predict the malignant nature of thymic epitherial tumors and suggest that the degree of FDG uptake in the thymic epitherial tumors is closely related to the amount of Glut-1 and HK-II in the tumor.  相似文献   
35.
36.
The FRhL-2 cell line, a diploid line derived from the lung of a fetal rhesus monkey, was used to prepare a potent rabies vaccine by adapting the Kissling strain of rabies virus to FRhL-2 cells, growing the virus in quantity, inactivating the virus with beta-propiolactone, and concentrating the virus by adsorption to aluminum phosphate. High levels of antibody to rabies virus, induced by the vaccine in both guinea pigs and humans at 14 days after immunization, were determined to be IgG. Data from postexposure protocols with guinea pigs and simulated postexposure protocols in humans showed protection and antibody response even when rabies immune globulin was administered at the time of vaccination.  相似文献   
37.
OBJECTIVE: To visualize and quantitatively analyze spatiotemporal dynamics of individual living monocytes during transendothelial migration (TEM). METHODS AND RESULTS: We developed an in vitro new experimental system using confocal laser scanning microscope with following two improvements: (1) ultra thin collagen gel layer (30-50 microm thick) constructed under human umbilical vein endothelial cell layer for three-dimensional observation with high magnification; (2) appropriate fluorescent labeling of living monocytes and endothelial cells to keep highest cell activity. Individual monocytes behaved quite diversely. Approximately 70% of adhered monocytes directionally crawled to intercellular junction, and started invasion. Time from adhesion to start of invasion was 8.6 +/- 5.4 min (mean +/- S.D., n=61 monocytes). Approximately 80% of such invading monocytes completed TEM, but remaining 20% of once invading monocytes hesitated transmigration, and returned onto the endothelial surface. Time from start to finish of invasion was 6.3 +/- 3.2 min (mean +/- S.D., n=53 monocytes). CONCLUSIONS: Using our collagen gel-based newly-developed system, we visualized and quantitatively analyzed detailed spatiotemporal, three-dimensional dynamics of individual living monocytes during TEM. We revealed that monocytes encountered at least two hurdles, at starting invasion, and leaving endothelium, to achieve complete TEM. Approximately 56% (80% of 70% of adhered monocytes) passed both hurdles.  相似文献   
38.
Right ventricular (RV) outflow tract obstruction (RVOTO) is an uncommon complication of lung transplantation in patients with pulmonary hypertension (PH) and both medical management and surgical intervention are required. A 28-year-old female with primary PH was referred and because she did not respond to medical treatment, living-donor lobar lung transplantation was performed. The operation was successful, but dyspnea and exercise intolerance developed during rehabilitation and transthoracic echocardiography revealed RVOTO. Intravenous disopyramide during cardiac catheterization reduced the pressure gradient from 35 mmHg to 16 mmHg without decreasing RV systolic pressure. However, electrical and hemodynamic parameters were adversely affected by disopyramide and thus, after cardiac catheterization, administration of fluid and a low dose of atenolol was started, and her symptoms improved. Transthoracic echocardiography showed improvement in the RVOTO. This case suggests that disopyramide should be avoided for patients with RVOTO following lung transplantation and that other negative inotropic agents, such as beta-blockers, are more effective for relief of RVOTO.  相似文献   
39.
Background The prognosis of elderly patients with chronic total occlusion (CTO) and diabetes mellitus (DM) treated with percutaneous coronary intervention (PCI) is not known. Objective To investigate the effect of diabetes on long-term follow-up of CTO after PCI in elderly patients. Methods A total of 153 elderly patients (age > 65 years old) with CTO lesions which were successfully treated with PCI were enrolled. Fifty one patients with diabetes and 102 without diabetes were compared for long-term outcomes (mean follow up: 36 ? 12 months). Major adverse cardiac events (MACE) which include death, myocardial infarction or target lesion revascularization (TLR) were considered as a combined endpoint. Results The combined endpoint occurred in 29.4% of diabetes patients, and 11.3% of the patients without diabetes (P < 0.05). The Cox proportional hazards model identified: drug eluting stent (DES) or bare metal stent (BMS) (HR: 0.13, 95% confidence interval (95% CI): 0.03–0.62, P = 0.004), DM (HR: 6.69, 95% CI: 1.62–15.81, P = 0.01) and final minimal lumen diameter (MLD) (HR: 0.37, 95% CI: 0.13–0.90, P = 0.03 ) as independent predictors of MACE, DM with renal impairment (HR: 6.64, 95% CI: 1.32–33.36, P = 0.02), HBA1C on admission (HR: 1.79, 95% CI: 1.09–2.94, P = 0.02), as independent predictors of MACE at long term follow-up. Conclusions相似文献   
40.
We report herein the case of a male neonate with a giant cystic lymphangioma confined to the bilateral anterior mediastinum. He developed very severe respiratory distress on the 8th day of life due to the mediastinal mass, and almost total excision of the bilateral mass was performed on the 12th day of life through a right axillar thoracotomy. The pathological diagnosis was cystic lymphangioma. Postoperatively, right phrenic nerve dysfunction was evident, for which diaphragmatic plication could only be performed 5 weeks after the initial surgery due to the prolonged respiratory support. In the 4 years since undergoing surgery the child has shown no sign of recurrence and has not experienced any further respiratory problems.  相似文献   
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