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61.
Cultured muscle fibers (CMF) from a patient with inclusion-body myositis (IBM) and cardiac amyloidosis associated with the transthyretin (TTR) Val122Ile mutation contained aspects of the IBM phenotype: vacuolation, congophilic inclusions, and clusters of immunocolocalizing amyloid beta-peptide (Abeta) and TTR accumulations. These abnormalities are never present in normal human CMF. These perturbations were greatly increased after Abeta precursor protein gene transfer. The TTR mutation may be a genetic predisposition factor for the patient's IBM. 相似文献
62.
RATIONALE AND OBJECTIVES: The authors performed this study to investigate the causes of interscan variability of coronary artery calcium measurements at electron-beam computed tomography (CT). MATERIALS AND METHODS: Two sets of electron-beam CT scans were obtained in 298 consecutive patients who underwent electron-beam CT to screen for coronary artery calcium. Interscan variations of coronary artery calcium characteristics and the effects of heart rate, electrocardiographic (ECG) triggering method, image noise, and coronary motion on interscan variability were analyzed. RESULTS: The interscan mean variabilities were 21.6% (median, 11.7%) and 17.8% (median, 10.8%) with the Agatston and volumetric score, respectively (P < .01). Variability decreased with increasing calcification score (34.6% for a score of 11-50 and 9.4% for a score of 400-1,000, P < .0001). The absolute difference in Agatston score between scans was 44.1 +/- 95.6. The correlation coefficient between the first and second sets of scans was 0.99 (P < .0001). Lower interscan variability was found in younger patients (<60 years), patients with stable heart rates (heart rate changing less than 10 beats per minute during scanning), patients with no visible coronary motion, and those with an optimal ECG triggering method (P < .05 for all). Results of multivariate logistic analysis showed that changes in calcium volume, mean attenuation, and peak attenuation were significant predictors of interscan variability and caused the interscan variations of the coronary artery calcium measurements (r2 = 0.83, P < .0001). CONCLUSION: Coronary calcification at electron-beam CT varies from scan to scan. Volumetric scoring and optimal ECG triggering should be used to reduce interscan variability. Baseline calcium score and interscan variability must be considered in the evaluation of calcium progression. 相似文献
63.
Gould DA Edwards RD McWilliams RG Rowlands PC Martin J White D Fear S Bakran A Brennan J Gilling-Smith G Harris PL 《Cardiovascular and interventional radiology》2000,23(5):358-363
Purpose: To investigate the incidence, significance, and mechanism of stent-graft distortion after endovascular repair (EVR) of abdominal
aortic aneurysm.
Methods: EVR of abdominal aortic aneurysm was performed in 51 cases (49 modular, bifurcated; 2 tube). Thirty-two patients were followed
for 6 or more months and had equivalent baseline and follow-up images which could be used to determine changes in graft configuration.
Sac dimensions were measured using computed tomographic (CT) images and graft-related complications were recorded.
Results: Amongst 32 patients evaluated on follow-up, there was graft distortion in 24. Distorted grafts were significantly (p= 0.002) associated with sac diameter reduction (mean 5 mm) and sac length reduction (mean 8.1 mm). All graft-related complications
occurred in the limbs of eight distorted grafts, with a mean reduction of sac length in this group of 7.8 mm on reformatted
CT images.
Conclusion: There was a highly significant association between graft distortion and limb complications, and reduced sac dimensions. 相似文献
64.
Bruce A Teitelbaum Daniel K Roberts Janis Ecklund Winters David D Castells Cathy Clark Alexander 《Optometry》2005,76(11):653-656
BACKGROUND: The adequate control of blood pressure in patients with diabetes mellitus (DM) is important to limit the ocular and systemic complications of the disease. Hypertension in African Americans is among the highest in the world. This cross-sectional study reports the level of blood pressure control in a small sample of African American patients with DM at an urban eye care facility using the criteria defined by the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC VII). METHODS: Five attending faculty members of the Illinois College of Optometry identified 234 African American patients with a diagnosis of DM over a period of 16 months. Blood pressure readings were recorded once at the time of their visit and were classified as controlled or uncontrolled based on the JNC VII cutoff of blood pressure less than 130/80 mmHg. RESULTS: Among the 234 African American patients in this study, 174 (74.4%) reported having DM and hypertension, and 60 (25.6%) reported having DM without hypertension. Of the patients with DM and a self-reported diagnosis of hypertension, 13.2% were controlled. Of the patients with diabetes without a self-reported diagnosis of hypertension, 26.7% were found to be adequately controlled. For the pooled data of 234 patients with diabetes, 16.7% met the JNC VII guidelines. CONCLUSION: The inadequate control of blood pressure in the African American population with DM is associated with increased disability and death from cardiovascular and renal disease. The results of this small cross-sectional study are consistent with those of other studies that show poor control of blood pressure in African American patients who have DM. Preventable blindness secondary to accelerated diabetic retinopathy from uncontrolled hypertension is a concern to all eye care practitioners. 相似文献
65.
Thirty patients were selected to bleach their maxillary teeth. Vacuum-formed trays were fabricated for the maxillary arch so that only one quadrant of bleaching tray had reservoirs. Nupro Gold 10% carbamide peroxide gel was given to patients. They were instructed to place a drop of gel in each tooth area and wear the trays twice a day for two-hour periods. After 10 days the patients were evaluated for shade changes in each quadrant. No clinical difference was observed in the after-shade match of the two quadrants. It appears that the addition of blockout spacers to create reservoirs does not increase the success of home bleaching. 相似文献
66.
Niedhammer I Siegrist J Landre MF Goldberg M Leclerc A 《Revue d'épidémiologie et de santé publique》2000,48(5):419-437
BACKGROUND: Two main models are currently used to evaluate psychosocial factors at work: the Job Strain model developed by Karasek and the Effort-Reward Imbalance model. A French version of the first model has been validated for the dimensions of psychological demands and decision latitude. As regards the second one evaluating three dimensions (extrinsic effort, reward, and intrinsic effort), there are several versions in different languages, but until recently there was no validated French version. The objective of this study was to explore the psychometric properties of the French version of the Effort-Reward Imbalance model in terms of internal consistency, factorial validity, and discriminant validity. METHODS: The present study was based on the GAZEL cohort and included the 10 174 subjects who were working at the French national electric and gas company (EDF-GDF) and answered the questionnaire in 1998. A French version of Effort-Reward Imbalance was included in this questionnaire. This version was obtained by a standard forward/backward translation procedure. RESULTS: Internal consistency was satisfactory for the three scales of extrinsic effort, reward, and intrinsic effort: Cronbach's Alpha coefficients higher than 0.7 were observed. A one-factor solution was retained for the factor analysis of the scale of extrinsic effort. A three-factor solution was retained for the factor analysis of reward, and these dimensions were interpreted as the factor analysis of intrinsic effort did not support the expected four-dimension structure. The analysis of discriminant validity displayed significant associations between measures of Effort-Reward Imbalance and the variables of sex, age, education level, and occupational grade. CONCLUSION: This study is the first one supporting satisfactory psychometric properties of the French version of the Effort-Reward Imbalance model. However, the factorial validity of intrinsic effort could be questioned. Furthermore, as most previous studies were based on male samples working in specific occupations, the present one is also one of the first to show strong associations between measures of this model and social class variables in a population of men and women employed in various occupations. 相似文献
67.
David W. Kennedy Janis L. Abkowitz 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(25):14944-14949
The goal of this study was to identify the circulating cell that is the immediate precursor of tissue macrophages. ROSA 26 marrow mononuclear cells (containing the β-geo transgene that encodes β-galactosidase and neomycin resistance activities) were cultured in the presence of macrophage colony-stimulating factor and flt3 Ligand for 6 days to generate monocytic cells at all stages of maturation. Expanded monocyte cells (EMC), the immature (ER-MP12+) and more mature (ER-MP20+) subpopulations, were transplanted into irradiated B6/129 F2 mice. β-gal staining of tissue sections from animals 15 min after transplantation demonstrated that the donor cells landed randomly. By 3 h, donor cells in lung and liver were more frequent in animals transplanted with ER-MP20+ (more mature) EMC than in animals transplanted with unseparated EMC or fresh marrow mononuclear cells, a pattern that persisted at 3 and 7 days. At 3 days, donor cells were found in spleen, liver, lung, and brain (rarely) as clusters as well as individual cells. By 7 and 14 days, the clusters had increased in size, and the cells expressed the macrophage antigen F4/80, suggesting that further replication and differentiation had occurred. PCR for the neogene was used to quantitate the amount of donor DNA in tissues from transplanted animals and confirmed that ER-MP20+ EMC preferentially engrafted. These data demonstrate that a mature monocytic cell gives rise to tissue macrophages. Because these cells can be expanded and manipulated in vitro, they may be a suitable target population for gene therapy of lysosomal storage diseases. 相似文献
68.
69.
Comparison of coronary artery calcium screening image quality between C-150 and e-Speed electron beam scanners 总被引:2,自引:0,他引:2
Budoff MJ Shinbane JS Oudiz RJ Child J Carson S Chau A Tseng P Gao Y Mao S 《Academic radiology》2005,12(3):309-312
RATIONALE AND OBJECTIVE: The newest generation of electron beam tomographic scanner (e-Speed) has increased spatial and temporal resolution compared with the C-150 XP scanner. The aim of this study was to evaluate coronary artery calcium screening image quality between the e-Speed and C-150 scanners (GE Imatron, San Francisco, CA). MATERIALS AND METHODS: Studies from 41 patients (14 women and 27 men) who underwent serial coronary artery calcium screening with the C-150 (first study) and the e-Speed (second study) were analyzed. Individual computed tomography (CT) slices were assessed for coronary artery motion artifacts, and CT Hounsfield units (HU) and noise values (CT HU standard deviation) at 16 discrete cardiac sites were measured and averaged. RESULTS: With the e-Speed scanner, there were significant decreases in right coronary artery motion artifacts compared with the C-150 scanner (0.3% versus 1.8%, P < .001) as well as decreased noise values (24.3 versus 32.0 HU, P < .001). CONCLUSION: Image quality is significantly improved with use of the e-Speed scanner, due to its improved temporal and spatial resolution, compared with the C-150 scanner. 相似文献
70.