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191.
192.
PURPOSE: Many studies have shown a positive association between cigarette smoking and oral diseases. Few studies, however, have focused on the relationship between passive smoking exposure and oral health in adults. We investigated the association of active and passive smoking exposure with tooth loss in Japan. METHODS: Study subjects were 1002 pregnant women. Tooth loss was defined as previous extraction of one or more teeth. Adjustment was made for age, gestation, parity, family income, education, and body mass index. RESULTS: Of the 1002 subjects, 256 women had lost one or more teeth. Current light smoking was independently related to an increased prevalence of tooth loss, showing a significant exposure-related association with smoking status. A significant positive association of 8 or more pack-years of smoking with the prevalence of tooth loss was observed. Also, a significant positive relationship was found between current heavy passive smoking at home and tooth loss, but not with pack-years of passive smoking at home. No measurable association between passive smoking exposure at work and tooth loss was indicated. CONCLUSIONS: The present findings suggest that passive as well as active smoking may be associated with an increased prevalence of tooth loss in Japanese young adult women.  相似文献   
193.
OBJECTIVE: 76 patients who underwent laminoplasty for cervical spondylotic myelopathy were investigated regarding the impact of preoperative and postoperative degenerative spondylolisthesis on their neurologic outcome. METHODS: Radiographs were obtained 1 year postoperatively to investigate range of motion (ROM), lordotic curvature, and postoperative spondylolisthesis. RESULTS: By 1 year after surgery, 85% of those spondylolistheses present preoperatively had either resolved or improved on neutral lateral radiographs. The cross-sectional area of the spinal cord at the site of spondylolisthesis was measured using preoperative computed tomography myelography. Clinical results were evaluated by the recovery rate using Japanese Orthopaedic Association score. Patients with posterior spondylolisthesis showed a significantly poorer postoperative recovery rate. Intervertebral ROM in patients with preoperative spondylolisthesis was reduced, whereas cervical alignment had not deteriorated after laminoplasty. The group with posterior spondylolisthesis showed a significant reduction in the cross-sectional area of the spinal cord at the site of spondylolisthesis. Postoperative spondylolisthesis appeared in 15 patients, 10 of whom had preoperative spondylolisthesis at an adjacent site. CONCLUSION: The cause of poorer surgical results of those patients with preoperative posterior spondylolisthesis appears to be related to a higher degree of spinal cord compression than with preoperative anterior spondylolisthesis.  相似文献   
194.
Objective: This study was undertaken to review our experience of mitral valve replacement in children under 3 years of age. Methods: Between January 1990 and May 2004,18 patients under 3 years of age underwent a total of 20 mitral valve replacements using a bileaflet mechanical prosthetic valve. There were 9 males and 11 females. The age at surgery ranged from 3 months to 3 (mean=1.02±0.72) years and body weight varied between 3.4 and 13.2 (mean=7.08±2.74) kg. Results: There were 4 early and 2 late deaths, and these occurred in severe cases aged less than 1 year of age. Re-replacement of mitral valve was required in 3 patients (valve thrombosis in 2 and pannnus formation in 1). Orifice size of the implanted prosthesis (OS) as compared with the predicted normal size of the mitral valve (NS) was well correlated with maximum transprosthetic flow velocity estimated by Doppler echocardiography. In this study, the OS/NS>0.65 was maintained in all patients, and none required re-replacement because of prosthesis-patient mismatch. Conclusion: Patients less than 1 year of age had significant mortality and morbidity. The results were satisfactory in the remainder (1–3 years). During this follow-up period, none required re-replacement due to somatic growth, but it will be an unavoidable problem in the future. The OS/NS, which can be checked with a regular physical examination, may serve as a guide to determine the most appropriate timing for the second surgery.  相似文献   
195.
196.
The influence of the intravenous injection of ranitidine (50 mg) on hepatic hemodynamics was investigated in normal subjects and patients with chronic liver disease. Using the organ-reflectance spectrophotometer, the regional hepatic blood hemoglobin concentration (delta Er569-650), an indicator of the regional hepatic blood flow, and the oxygen saturation of hemoglobin in the regional hepatic tissue (So2) were measured in patients with chronic liver disease after ranitidine injection under peritoneoscopy. With the pulse-Doppler ultrasonic flowmeter, the portal blood flow was measured in patients with chronic liver disease and normal subjects. There were no significant changes in the regional hepatic blood flow, the oxygen saturation of hemoglobin, and the portal blood flow after the intravenous injection of ranitidine. Thus, it is concluded that usual dose of ranitidine has no significant influence on the hepatic blood flow and that it can be prescribed without reducing the hepatic blood flow.  相似文献   
197.
Olfactory transmission of neurotropic viruses   总被引:2,自引:0,他引:2  
Olfactory receptor neurons are unique in their anatomical structure and function. Each neuron is directly exposed to the external environment at the site of its dendritic nerve terminals where it is exposed to macromolecules. These molecules can be incorporated into by olfactory receptor neurons and transported transsynaptically to the central nervous system. Certain neurotropic pathogens such as herpes simplex virus and Borna disease virus make use of this physiological mechanism to invade the brain. Here the authors review the olfactory transmission of infectious agents and the resulting hazards to human and animal health.  相似文献   
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Hama Y  Kusano S 《Military medicine》2005,170(8):713-714
OBJECTIVES: To assess the students' perceptions and evaluations of radiology lectures and to determine the factors correlating with performance on examinations. METHODS: Sixty-three nursing students were asked to submit their opinions regarding the lecture at the end of each lecture, and they were asked to evaluate the lectures as a whole at the end of the course. Relationships between each of the survey items (student curiosity, overall understanding, usefulness of the lecture, difficulty level, incentive to study, and total number of opinions regarding the lecture) and the final examination score were examined with Spearman correlation analysis. RESULTS: Statistically significant positive correlations were found between student curiosity and the final examination score (n = 62, rs = 0.281, p < 0.028) and between the total number of opinions and the final examination score (n = 63, rs = 0.273, p < 0.032). However, the other variables did not reach statistical significance. CONCLUSIONS: Our results suggest that lectures enhancing student curiosity and eliciting feedback from students may be related to high performance on examinations.  相似文献   
200.
Visualization of the lower cranial nerves by 3D-FIESTA   总被引:5,自引:0,他引:5  
MR cisternography has been introduced for use in neuroradiology. This method is capable of visualizing tiny structures such as blood vessels and cranial nerves in the cerebrospinal fluid (CSF) space because of its superior contrast resolution. The cranial nerves and small vessels are shown as structures of low intensity surrounded by marked hyperintensity of the CSF. In the present study, we evaluated visualization of the lower cranial nerves (glossopharyngeal, vagus, and accessory) by the three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) sequence and multiplanar reformation (MPR) technique. The subjects were 8 men and 3 women, ranging in age from 21 to 76 years (average, 54 years). We examined the visualization of a total of 66 nerves in 11 subjects by 3D-FIESTA. The results were classified into four categories ranging from good visualization to non-visualization. In all cases, all glossopharyngeal and vagus nerves were identified to some extent, while accessory nerves were visualized either partially or entirely in only 16 cases. The total visualization rate was about 91%. In conclusion, 3D-FIESTA may be a useful method for visualization of the lower cranial nerves.  相似文献   
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