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51.
52.
This study investigated correlations between American Spinal Injury Association (ASIA) clinical injury motor scores in patients with traumatic cervical cord injury and magnetic resonance (MR) diffusion tensor imaging (DTI) parameters. Conventional imaging and DTI were performed to evaluate 25 patients (age, 39.7±13.9 years; 4 women, 21 men) with blunt spinal cord injury and 11 volunteers (age, 31.5±10.7 years; 3 women, 8 men). Cord contusions were hemorrhagic (HC) in 13 and non-hemorrhagic (NHC) in 12 patients. The spinal cord was divided into three regions to account for spatial and pathological variation in DTI parameters. Comparisons of regional and injury site mean diffusivity (MD), fractional anisotropy (FA), radial diffusivity ( λ(⊥)), and longitudinal diffusivity ( λ(‖)) were made with control subjects. ASIA motor scores were correlated with DTI using linear regression analysis. HC and NHC patients showed significant reduction (p<0.001) in MD and λ(‖) in all three regions. At the injury site, significant decreases in FA and λ(‖) were seen for both injury groups (p<0.001). λ(⊥) values were significantly increased only for patients with NHC (p<0.05). Significant reduction in FA and λ(‖) (p<0.0001) was observed at the whole cord level between the injured (NH and NHC) and control groups. Within the NHC group, strong correlations were observed between ASIA motor scores and average MD, FA, λ(⊥), and λ(‖) at the injury site. However, no correlation was observed within the HC group between any of the DTI parameters and ASIA motor scores. DTI parameters reflect the severity of spinal cord injury and correlate well with ASIA motor scores in patients with NHC.  相似文献   
53.
The purpose of this retrospective study was to determine the CT findings diagnostic of cardiac and pericardial injury, including signs of pericardial tamponade, in patients suffering from blunt and penetrating trauma. A search of the CT radiology database at a level I trauma center was performed to identify cases in which injury to the heart or pericardium was diagnosed, as well as to identify cases of pericardial tamponade. All cases were reviewed to ascertain the specific CT findings, and medical records were reviewed to assess the influence of CT findings on management and to assess for clinical evidence of pericardial tamponade. Eighteen patients had direct CT evidence of cardiac or pericardial injury, including nine cases of pneumopericardium, eight cases of hemopericardium, and one case of intrapericardial gastric herniation. Four of these patients were found to have direct cardiac injuries. Three additional cases with CT evidence of pericardial tamponade were identified, two secondary to cardiac compression by an anterior mediastinal hematoma and one following repair of left ventricular rupture. Of 11 patients with CT evidence of tamponade, only three were suspected clinically. Cardiac and pericardial injuries are usually diagnosed surgically and are often clinically unsuspected, particularly in blunt trauma. As CT is increasingly utilized as a general screening test for thoracic/abdominal trauma, these injuries may be first suspected on the basis of CT findings, and knowledge of the CT findings of cardiac injury or tamponade is crucial.  相似文献   
54.
Portable CT: assessing thoracic disease in the intensive care unit.   总被引:1,自引:0,他引:1  
OBJECTIVE: The objective of this study was to assess the usefulness of a portable CT scanner to evaluate and treat thoracic disease in patients in the intensive care unit. MATERIALS AND METHODS: Fourteen patients who were being treated in the intensive care unit underwent 20 portable CT scans. Twice a CT scan was obtained to guide an interventional chest procedure. The remaining 18 scans were assessed for findings not evident on portable chest radiography and for findings that altered treatment. Image quality was judged in comparison with fixed CT scans. RESULTS: Unsuspected abnormalities, most relating to the pleura or chest wall, were found in 13 of the 17 available portable CT scans. Treatment was affected in four (25%) of the 16 cases in which medical records were available for review. Two interventional procedures were performed successfully using portable CT guidance. Scan quality was judged to be comparable with that of fixed CT for mediastinal windows and somewhat inferior for lung windows. CONCLUSION: Portable CT gives images of diagnostic quality and allows confident guidance during interventional procedures in critically ill patients who therefore need not leave the intensive care unit environment.  相似文献   
55.
We discovered an emerging non-metropolitan mortality penalty by contrasting 37 years of age-adjusted mortality rates for metropolitan versus nonmetropolitan US counties. During the 1980s, annual metropolitan-nonmetropolitan differences averaged 6.2 excess deaths per 100,000 nonmetropolitan population, or approximately 3600 excess deaths; however, by 2000 to 2004, the difference had increased more than 10 times to average 71.7 excess deaths, or approximately 35,000 excess deaths. We recommend that research be undertaken to evaluate and utilize our preliminary findings of an emerging US nonmetropolitan mortality penalty.  相似文献   
56.
Most discussions on the relationships between health and economic conditions have focused on the impact of differences in personal finances or national economic conditions on health. Recently, however, the role of health as an 'economic engine' has been promoted. This paradigm proposes that better health leads to economic development. Evidence from historical, national, and transnational studies have shown that improved health increases economic growth through impacts on micro- and macro-economic factors. In this review, we will summarize the evidence supporting these concepts as a basis for discussing their implications for underdeveloped regions within the United States.  相似文献   
57.
This article emphasizes multirow detector CT (MDCT) technique, the spectrum of findings for diagnosing major thoracic vascular injuries, and the challenges and potential errors that might be encountered. In particular, the role of MDCT data after processing to enhance diagnostic accuracy and convey appropriate and required diagnostic information to the doctors who are managing these vascular injuries are discussed.  相似文献   
58.

Introduction

Cerebral fat embolism syndrome (CFES) mimics diffuse axonal injury (DAI) on MRI with vasogenic edema, cytotoxic edema, and micro-hemorrhages, making specific diagnosis a challenge. The objective of our study is to determine and compare the diagnostic utility of the conventional MRI and DTI in differentiating cerebral fat embolism syndrome from diffuse axonal injury.

Methods

This retrospective study was performed after recruiting 11 patients with severe CFES and ten patients with severe DAI. Three trauma radiologists analyzed conventional MR images to determine the presence or absence of CFES and DAI. DTI analysis of the whole-brain white matter was performed to obtain the directional diffusivities. The results were correlated with clinical diagnosis to determine the diagnostic utility of conventional MRI and DTI.

Results

The sensitivity, specificity, and accuracy of conventional MRI in diagnosing CFES, obtained from the pooled data were 76, 85, and 80 %, respectively. Mean radial diffusivity (RD) was significantly higher and the mean fractional anisotropy (FA) was lower in CFES and differentiated subjects with CFES from the DAI group. Area under the receiver operating characteristic (ROC) curve for conventional MRI was 0.82, and for the differentiating DTI parameters the values were 0.75 (RD) and 0.86 (FA), respectively.

Conclusions

There is no significant difference between diagnostic performance of DTI and conventional MRI in CFES, but a difference in directional diffusivities was clearly identified between CFES and DAI.  相似文献   
59.
Cigarette smoking is a risk factor for development of coronary atherosclerosis. We examined the relationship between smoking and the anatomic location of coronary artery stenosis in 8,705 patients undergoing cardiac catheterization for suspected coronary artery disease (CAD). The smoking history of patients with CAD (greater than or equal to 70 percent stenosis) was compared with that of control subjects (0 percent stenosis) for each of nine anatomic locations (proximal, middle, and distal segments of right [RCA], anterior descending [LAD], and circumflex arteries [LCX]), using a case-control method. The odds ratio (OR) estimate of relative risk of CAD for smokers relative to nonsmokers was 2.8, with a 95 percent confidence interval (CI) of 2.5 to 3.1. Relative risk was greater for RCA stenosis (OR = 5.8; CI = 4.6-7.2) than for LCX (OR = 3.5; CI = 2.7-4.5) or LAD (OR = 2.1; CI = 1.8-2.4) lesions when comparing smokers with nonsmokers. After control for age, gender, history of diabetes mellitus, and serum cholesterol level, the adjusted relative risk for an RCA lesion (Mantel-Haenszel odds ratio [MOR] = 4.9) was significantly elevated (p less than 0.05) compared with the LAD (MOR = 1.9) but not with the LCX (MOR = 3.1). The relative risks of CAD were the same (p greater than 0.05) for the proximal, middle, and distal coronary segments. Thus, smoking increased the risk of all coronary lesions but did so more for the RCA than for other vessels, suggesting a spatial pattern to the increased risk produced by smoking.  相似文献   
60.
Current recommendations for the plain radiographic evaluation of abdominal pain suggest a minimum three-film series including an erect and supine abdominal view and an erect chest study. Three film radiographic abdominal "series" were obtained in 252 consecutive emergency-room patients who presented with abdominal pain. The views were analyzed independently for their relative diagnostic value. Radiologic pathologic findings were present in 20% of the abdominal films and in 13% of the chest radiographs. The supine abdominal view and the erect chest study diagnosed normality or abnormality in 98% of these patients. The elimination of the erect abdominal view from the routine abdominal series could result in financial savings, decreased radiation exposure, and a more efficient use of technician time, without significant loss of diagnostic information.  相似文献   
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