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941.
942.
Tc-99m sestamibi gated SPECT in patients with left bundle branch block   总被引:4,自引:0,他引:4  
PURPOSE: The purpose of this study was to assess the diagnostic role of a Tc-99m sestamibi gated SPECT technique in patients with left bundle branch block (LBBB) without known coronary artery disease. MATERIALS AND METHODS: Twenty consecutive patients with constant complete LBBB were included. A same-day rest-stress protocol was used, and dipyridamole stress (14 patients) or treadmill exercise (6 patients) was applied. Electrocardiograph (ECG)-gated SPECT images were acquired 15 minutes after the administration of 0.31 mCi/kg Tc-99m sestamibi at peak stress. Regional myocardial perfusion was analyzed in relation to the cardiac cycle. RESULTS: Eleven of 14 patients who underwent a dipyridamole stress test had hypoactivity in the left anterior descending (LAD) artery territory in the ungated (summed) stress-rest images (abnormality ratio, 78%). On the ungated images, the abnormality was completely reversible in one patient (9%), partially reversible in five patients (46%), irreversible in two patients (18%), and reverse perfusion was identified in three patients (27%). Abnormality ratios of end-systolic and end-diastolic data were 93% and 29%, respectively. Conversely, the ungated rest-stress and end-systolic images of all the patients who performed treadmill exercise were abnormal despite the presence of normal or nearly normal end-diastolic myocardial perfusion. The angiographic findings correlated best with those of end-diastolic images. In 13 patients without coronary artery disease, normal or nearly normal regional perfusion was observed on end-diastole, but four patients with abnormal end-diastolic perfusion, which involved the LAD territory in all but one, had substantial coronary artery disease. The number of the involved segments was similar on the end-systolic and ungated data. Most of these artifactual defects were localized to the anteroseptal, septal, and inferoseptal segments. CONCLUSIONS: These preliminary data indicate that end-diastolic images can significantly reduce artifactual defects in patients with LBBB. The resolution of an LBBB pattern on end-diastolic data would significantly improve the diagnostic role of myocardial perfusion studies in these patients.  相似文献   
943.
PURPOSE: In this study, changes in antioxidant systems due to free radicals were investigated in short distance (100-m) and long-distance (800-m) swimmers, within whom the anaerobic and aerobic metabolisms dominate, respectively. METHODS: For this study, swimmers aged between 15 and -21 yr swam 800 m (N = 10) and 100 m (N = 9). Venous blood samples were taken before swimming, and at 1-, 20-, and 40-min intervals after swimming. Lactate, catalase (CAT), glutathione peroxidase (GPx), and reduced glutathione (GSH) levels were determined in the blood samples. RESULTS: The increase of lactate levels was statistically significant in the swimmers, both after the 100- and 800-m distances as compared with the preswimming levels (P < 0.001, P < 0.001). Catalase activity was increased in the first minute postswimming as compared with preswimming levels. Catalase activity then decreased at the 20- and 40-min intervals as compared with the 1-min postswimming interval, at both 100- and 800-m distances (P < 0.01, P < 0.001). GPx activity was also increased in the first minute after swimming as compared with preswimming levels. GPx activity then decreased at the 20- and 40-min intervals when compared with the 1-min postswimming level. This occurred in both 100- and 800-m swimmers (P < 0.001, P < 0.001). GSH activity was decreased in the first minute after swimming, compared with the preswimming levels. GSH activity then increased at the 20- and 40-min postswimming intervals, as compared with the first-minute level. Again, this occurred in both the 100- and 800-m swimmers (P < 0.001, P < 0.01). CONCLUSION: We concluded that both long-distance and particularly short-distance (100-m) swimming increased the activities of antioxidant defense enzymes.  相似文献   
944.
An unusual case is reported of a 53-year-old woman presenting with spinal tuberculosis involving cervical, thoracic and lumbar vertebrae. The patient originally presented with progressive quadriparesis, fever, night sweats and weight loss. Imaging studies demonstrated vertebral body destruction with and without paraspinal and/or intraspinal abscess in cervical, thoracic and lumbar regions. The laboratory studies confirmed the diagnosis of Pott's disease and the patient was placed on anti-tuberculosis chemotherapy. The anterior approach was used for removal of the infected necrotic material, bone grafting and instrumentation, in both cervical and thoracic vertebrae. The postoperative course was uneventful and the patient made an excellent neurological recovery. The present report is of the first published case of an extensive spinal tuberculosis involving cervical, thoracic and lumbar spine.  相似文献   
945.
Breast cancer metastatic to the cervix and uterus in the absence of extrapelvic foci is a rare finding in the medical literature. Signet ring breast carcinoma is also an unusual neoplasm. We present an asymptomatic 71-year-old woman 2 years status-post modified radical mastectomy for signet ring carcinoma who was found to have metastatic lesions to the cervix and endometrium at the time of a routine gynecological examination. Bone scan as well as computerized tomography of the chest, abdomen, and pelvis failed to locate other metastatic sites. We believe this to be the only reported case of signet ring breast carcinoma metastatic solely to the uterus and cervix. The patient's lack of recent pelvic examination highlights the need for continued gynecological evaluation in patients with breast cancer.  相似文献   
946.
947.
Eosinophilic fasciitis--progression to linear scleroderma: a case report   总被引:1,自引:0,他引:1  
Eosinophilic fasciitis is a rare disease in children. Although changes similar to linear scleroderma have been reported, the outcome is usually good. In this report, a 10-year-old boy who developed eosinophilic fasciitis without a good response to steroids is presented. He progressed to linear scleroderma within months. Our case reinforces the hypothesis that eosinophilic fasciitis may be an early manifestation or a variant of localized scleroderma similar to the other cases in the literature.  相似文献   
948.
OBJECTIVE: The object of this study was to determine the prevalence of otitis media with effusion (OME) in first and second grade primary school students, to analyze the causes of the difference in the prevalence, to define the effect of OME on the academic performance of the children and to investigate a correlation between the prevalence of OME and Bacillus Calmette-Guerin (BCG) vaccination. STUDY PLAN AND METHODS: The study was conducted during the September-November, 2002 period in Elazig. A total of 3675 clinically healthy primary school children attending primary schools in the central district of Elazig, living in the same region and of a similar socioeconomic status and age group were included in the study. Of the 3675 children, 2042 were in their first and 1633 in their second grade of primary school. The routine ear-nose and throat examinations of the children were carried out at their schools by the same medical team. The tympanometric test was performed in children diagnosed with OME following otoscopic examination. A scale measuring the academic performance of the children was developed. This scale was filled in by the student's teachers prior to physical examination. RESULTS: OME was diagnosed in 64 out of 2042 (3.1%) first grade and in 25 out of 1633 (1.5%) second grade students. The difference between the percentages of OME in first and second grade students was statistically significant (P < 0.05). The frequency of other ear-nose and throat pathologies accompanying OME was similar to those in children without OME. There was no statistically significant difference between the academic performances of children with and without OME (P > 0.05). CONCLUSION: The analysis of risk factors for OME revealed no difference between first and second grade students. The reason for the difference in the prevalence of OME between first and second grade students may be the positive effect on the immune system of the BCG vaccine which had been administered to the second grade students 4 months previously.  相似文献   
949.
950.
We intended to study the effect of swimming exercise on the brain, liver and heart malondialdehyde (MDA) levels which are the last product of oxidation, and to compare them with the brain, liver and heart MDA levels of controls. The experiments were carried out on 20 Wistar rats which were fed with a standard laboratory chow diet ad libitum. Rats were distributed in two groups, control group (n = 10) and exercise group (n = 10). The exercise group rats were exposed to swimming exercise for 30 minutes. After this animals in each group were sacrificed by decapitation, their brain, liver and heart tissues were quickly removed. MDA levels of the brain, liver and heart were determined according to the method in which MDA reacts with thiobarbituric acid. Results were evaluated by the Mann-Whitney U test. The liver and heart MDA levels in the exercise group were (29.59+/-6.73 and 10.49+/-1.90 nmol/g tissue, respectively) significantly higher than in the control group (21.78+/-3.46 and 8.86+/-1.25 nmol/g tissue, p<0.01 and p<0.05, respectively). However, the brain MDA levels were similar in both groups (exercise group 19.37+/-5.50 nmol/g tissue and control group 16.58+/-2.44 nmol/g tissue; p=0.325). It is concluded that swimming exercise might cause oxidative stress.  相似文献   
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