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41.
BACKGROUND: Uncoupling proteins (UCPs) reduce ATP generation with concomitant increased release of heat. The activities of UCPs have been related to obesity and energy metabolism. METHODS: We investigated the association of the commonly observed UCP2 Ala55Val (V) polymorphism with diabetes mellitus and impaired fasting glucose (IFG) among 3684 participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study. RESULTS: The V frequency was approximately 45% in blacks and 42% in whites. Those with the Val/Val (VV) genotype had a higher incidence of diabetes than those having the Ala/Ala (AA) genotype (5.8% vs 3.3%; P = 0.02). Similarly, the incidences of diabetes in participants without abdominal obesity were 2.8% and 1.0% (P = 0.03) in the VV and AA groups, and 12.4% and 8.3% (P = 0.15) in participants with abdominal obesity. The incidence of IFG was higher in VV vs AA only in those without abdominal obesity (12.9% vs 9.2%). These trends persisted in minimally and fully adjusted models, and in strata of blacks and whites and men and women. The homeostasis model assessment for insulin resistance was highest in VV in the combined group of those with IFG or untreated diabetes, but not in those with normal fasting glucose. CONCLUSION: The VV genotype of the UCP2 polymorphism was positively related to diabetes. It may involve increased insulin resistance in those with impaired glucose homeostasis.  相似文献   
42.

Background  

The objective of this study was to assess the status of oxidative stress in term small for gestational age (SGA) newborn infants born to undernourished mothers by estimating levels of erythrocyte superoxide dismutase (SOD), catalase, reduced glutathione, and serum malondialdehyde (MDA) in cord blood and comparing them to healthy appropriate for gestational age (AGA) controls. This was done in a case control design at a tertiary level teaching hospital.  相似文献   
43.
44.
BACKGROUND: False-positive, false-negative, and indeterminate fine-needle aspiration (FNA) biopsy results complicate the management of patients with thyroid nodules. METHODS: Thyroid FNA results from 240 consecutive patients (seen 1991 to 2002) were categorized into four groups: positive for malignancy, negative for malignancy, indeterminate for malignancy, and nondiagnostic. Indeterminate results included follicular neoplasm, Hürthle cell neoplasm, and suspicious for papillary carcinoma. The FNA results were compared with histopathologic analysis after thyroidectomy. RESULTS: The FNA results were 76 (32%) positive for malignancy, 53 (22%) negative for malignancy, 100 (42%) indeterminate for malignancy, and 11 (5%) nondiagnostic. There were 3 (4%) false-positive and 2 (4%) false-negative FNA results. Among the 100 indeterminate FNA results, carcinoma was found in 11 (15%) of 73 follicular neoplasms, 2 (20%) of 10 Hürthle cell neoplasms, and 14 (82%) of 17 suspicious for papillary carcinoma. For the 73 patients with follicular neoplasms, nodule diameter >2 cm was associated with an increased risk of malignancy (P <0.03). CONCLUSIONS: False-negative FNA results are uncommon, supporting the practice of observation in most of these patients. Among those with indeterminate biopsy results, high-risk subgroups include patients with FNA results suspicious for papillary carcinoma and follicular neoplasms >2 cm.  相似文献   
45.
46.
Background Schizophrenia is a common mental illness with an incidence of 15 new cases per 100,000 population per year. Aim To review evidence for current neurodevelopmental models of the aetiology of schizophrenia. Methods We performed a literature search using Medline and PsychINFO. We evaluated the relevance of each article and tracked other relevant articles through references. Results There is considerable evidence to support neurodevelopmental models of the aetiology of schizophrenia. One or more aetiological events occur between conception and birth that disturb central nervous system (CNS) development, leading to persisting alterations in brain structure and function. These early events, acting in concert with genetic loading and later influences or insults, predispose to the development of schizophrenia in early adulthood. Conclusions There have been considerable advances in schizophrenia research over the past 20 years. Future study of indices of neural development will help advance our understanding of this common, disabling mental illness.  相似文献   
47.
Radiofrequency ablation of solid tumors is produced by frictional heating caused when ions in the tissue attempt to follow the changing directions of a high-frequency alternating current. The radiofrequency probe is typically placed under ultrasound guidance, and the ablation is performed with real-time ultrasound monitoring. Radiofrequency ablation has been demonstrated to be effective in the treatment of unresectable hepatic tumors, and promising results have also been obtained in tumors of the lung, bone, brain, kidney, prostate gland, and pancreas. Most recently, radiofrequency ablation has been tested in the treatment of invasive breast tumors. A preliminary study reported that intraoperative radiofrequency ablation causes invasive breast cancer cell death in patients with locally advanced breast cancer. An ongoing study is investigating the use of radiofrequency ablation for the treatment of breast tumors 2 cm or less in diameter.  相似文献   
48.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns.  相似文献   
49.
B D Fornage  O Toubas  M Morel 《Cancer》1987,60(4):765-771
Clinical, mammographic, and sonographic preoperative size measurements were correlated with the values obtained at pathologic examination in a series of 31 patients with pathologically T1 (n = 23) and T2 (n = 8) breast carcinomas. Sonographic measurements demonstrated the highest correlation coefficient (r = 0.84), with the lowest residual standard deviation calculated in relation to the regression line. As a result, real-time sonography yielded the most accurate determination of breast cancer size in this series. Sonographic tumor size determination has proved valuable when mammography failed to delineate the tumor, particularly in patients with dense breasts. It may also be recommended in the evaluation of tumor response to nonsurgical conservative treatment.  相似文献   
50.
Myocardial tagging in polar coordinates with use of striped tags   总被引:1,自引:0,他引:1  
Bolster  BD  Jr; McVeigh  ER; Zerhouni  EA 《Radiology》1990,177(3):769-772
Regional deformation abnormalities in the heart wall provide a good indicator of ischemia. Myocardial tagging with magnetic resonance imaging is a new method of assessing heart wall motion during contraction. Current methods of myocardial tagging either do not provide two-dimensional information or lack a coordinate system well adapted to the morphology of the heart. In this article, the authors describe a new tagging method that provides a true polar coordinate system, with both radial and angular dimensions. This is accomplished with use of a section-selective version of spatially modulated magnetization resulting in striped tags (STAGs). These STAG planes are placed in the myocardium in a star pattern so that they intersect on the long axis of the heart and stripes appear through the width of the heart wall. In the short-axis view during contraction, rotation around the long axis yields angular information such as shear and twist, while separation of the stripes within the myocardium permits measurement of radial thickening. Therefore, this method provides a coordinate system for calculating two-dimensional strain that is adapted to the morphology of the left ventricle.  相似文献   
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