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51.
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This paper presents data on the characteristics, work activities, job-related stress, work satisfaction, and career aspirations of 150 faculty and 595 housestaff physicians who regularly provide continuous primary care in 15 teaching hospital-based group practices. The faculty were young, board-certified generalists; they had been recruited from local training programs and spent the majority of their time seeing patients and supervising housestaff. Job satisfaction among faculty and housestaff was generally high. Dissatisfaction occurred most often with aspects of work over which physicians had little control. Although work-related stress was common, it was not related to job satisfaction. Compared with housestaff in traditional residency programs, housestaff enrolled in special Primary Care Training Programs reported significantly greater job satisfaction. For all housestaff, satisfaction with work in the group practice was consistently associated with decreased interest in subspecialty training. assisted in preparing this report. Received from the Department of Medicine and the School of Public Health, UCLA Center for the Health Sciences. Los Angeles. California. Supported by Grant #59082 from the Robert Wood Johnson Foundation. The views expressed herein do not necessarily represent those of the Robert Wood Johnson Foundation.  相似文献   
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Spinal manipulation for low-back pain.   总被引:8,自引:0,他引:8  
PURPOSE: To review the use, complications, and efficacy of spinal manipulation as a treatment for low-back pain. DATA IDENTIFICATION: Articles were identified through a MEDLINE search, review of articles' bibliographies, and advice from expert orthopedists and chiropractors. STUDY SELECTION: All studies reporting use and complications of spinal manipulation and all controlled trials of the efficacy of spinal manipulation were analyzed. Fifty-eight articles, including 25 controlled trials, were retrieved. DATA ANALYSIS: Data on the use and complications of spinal manipulation were summarized. Controlled trials of efficacy were critically appraised for study quality. Data from nine studies were combined using the confidence profile method of meta-analysis to estimate the effect of spinal manipulation on patients' pain and functional outcomes. RESULTS OF DATA SYNTHESIS: Chiropractors provide most of the manipulative therapy used in the United States for patients with low-back pain. Serious complications of lumbar manipulation, including paraplegia and death, have been reported. Although the occurrence rate of these complications is unknown, it is probably low. For patients with uncomplicated, acute low-back pain, the difference in probability of recovery at 3 weeks favoring treatment with spinal manipulation is 0.17 (for example, increase in recovery from 50% to 67%; 95% probability limits of estimate, 0.07 to 0.28). For patients with low-back pain and sciatic nerve irritation, the difference in probabilities of recovery at 4 weeks is 0.098 (probability limits, -0.016 to 0.209). CONCLUSIONS: Spinal manipulation is of short-term benefit in some patients, particularly those with uncomplicated, acute low-back pain. Data are insufficient concerning the efficacy of spinal manipulation for chronic low-back pain.  相似文献   
55.
OBJECTIVES: To define the utility of transesophageal echocardiography in predicting the likelihood of a successful procedure and residual shunting in patients undergoing transcatheter closure of defects within the oval fossa using the CardioSEAL device. BACKGROUND: Transesophageal echocardiography is used to monitor transcatheter closure of interatrial defects within the the oval fossa, but predictors of successful closure and residual shunting have yet to be determined. METHODS: We reviewed transesophageal echocardiograms obtained from 26 consecutive patients undergoing attempted transcatheter closure of interatrial defects within the oval fossa between January, 1997 and May, 1998. Assessment of the atrial septum, the septal defect, and the rims of the oval fossa bordering the defect was performed in 3 planes: longitudinal, 4-chamber, and basal short-axis. RESULTS: Closure proved successful in 24 patients (92%). The defect was significantly larger, and the anterosuperior rim of the defect smaller, in the 2 patients in whom occlusion was not successful. Residual shunting 24 hrs after closure was detected in 14 patients. Significant predictors of leakage included smaller posterior and superior rims, a larger shunt prior to closure, and herniation of a one left atrial arm of the device into the right atrium. In all cases, the sites of leakage were the superior rim of the defect at the superior cavo-atrial junction, and the anterosuperior rim behind the aortic root. Herniation of a left atrial arm into the right atrium was seen in 7 patients (29%). In all, it was the anterosuperior arm which herniated Doppler color flow was suboptimal in detecting residual leaks, and was enhanced substantially with the use of contrast echocardiography. CONCLUSIONS: Transesophageal echocardiography allows excellent assessment of the oval fossa and deficiencies of its floor in all of their dimensions. It is an important tool for guiding the deployment of the occlusion device in patients undergoing attempted transcatheter closure of defects within the fossa. Contrast echocardiography should be used for optimal detection of residual shunting.  相似文献   
56.
M Aviram  J G Brook 《Artery》1983,11(4):297-305
Platelet aggregation as well as [14C] serotonin release were increased in platelet-rich plasma in comparison to gel-filtered platelet preparation. The addition of red blood cells to platelet-rich plasma enhanced thrombin-induced [14C] serotonin release by 7%, whereas in a gel-filtered platelet preparation free of any plasma constituents a 47% increment was noted. In the presence of white blood cells, no effect could be shown. Purified lipoproteins were incubated (in their normal plasma concentration) with gel-filtered platelets for 30 minutes at 37 degrees C, and the effect on in vitro platelet function was studied. Very low density lipoprotein and low density lipoprotein increased thrombin-induced platelet aggregation and [14C] serotonin release induced by epinephrine, ADP, and thrombin. In contrast, high density lipoprotein inhibited these platelet functions. Lipoprotein-deficient plasma increased platelet aggregation and release reaction. It appears that plasma lipoproteins have a profound effect on in vitro platelet function. Since both platelets and lipoproteins are of importance in atherosclerosis, the platelet-lipoprotein interaction might be of major significance in this process.  相似文献   
57.
A patient manifesting the arthropathy of hemochromatosis without abnormal serum iron studies is described. Hemochromatosis was confirmed by liver biopsy. This case serves to emphasize the diagnostic value of the characteristic arthropathy of hemochromatosis. Our observations in this patient support the hypothesis that the pathogenesis of hereditary hemochromatosis differs from that of acquired iron overload states. The concurrent presence of hypouricemia is explored in this patient and in 18 other patients with hereditary hemochromatosis. Men with hereditary hemochromatosis were found to have lower serum uric acid levels than expected. In our patient, a renal defect in tubular reabsorption of uric acid appears responsible for hypouricemia.The apparent association of hemochromatosis and hypouricemia deserves further investigation.  相似文献   
58.
The importance of timing in melatonin administration in a blind man   总被引:1,自引:0,他引:1  
An 18-year-old blind man suffered from chronic sleep disturbances associated with daytime fatigue and excessive daytime somnolence. After two unsuccessful treatment regimens with 5 mg and 10 mg melatonin administered at bedtime (2200-2230), a third regimen of 5 mg melatonin administered at 2000 for 3 weeks resulted in a successful resolution of his sleep disturbances. We suggest that the efficacy of melatonin in ameliorating sleep disturbances because of alterations in circadian rhythmicity may be dependent on the time of administration.  相似文献   
59.
OBJECTIVE: To investigate the prevalence of subclinical atherosclerosis among patients with psoriatic arthritis (PsA). METHODS: Forty patients with PsA were enrolled. Controls were matched by age, sex, and atherosclerotic risk factors. All patients and controls underwent duplex scan of the carotid arteries. Carotid intima-media thickness (IMT) was evaluated and the presence of atherosclerotic plaques was recorded. The plaques were graded and carotid plaque index was calculated. RESULTS: Patients with PsA had a higher IMT (mean +/- standard deviation, 1.04 +/- 0.35 mm vs 0.88 +/- 0.29 mm in controls; p = 0.03), and had a higher carotid plaque index than did matched controls (2.3 +/- 2.6, compared to 1.12 +/- 2.09; p = 0.03). Multivariate analysis demonstrated that PsA status as well as age and triglyceride levels were associated with the presence of carotid plaque. Other traditional risk factors were more prevalent among patients with PsA; however, they were not statistically significant. CONCLUSION: Our study demonstrates that patients with PsA may have an increased prevalence of subclinical atherosclerosis. These findings may not be solely attributable to traditional risk factors alone. Special attention and strict control of atherosclerotic risk factors in patients with PsA is warranted.  相似文献   
60.
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