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BACKGROUND: Early color M-mode Doppler flow propagation (Ep) through the left ventricle (LV) has been proposed as a useful noninvasive index for assessing LV relaxation, whereas data concerning late velocity propagation (Ap) is lacking. METHODS: We studied 51 patients with delayed relaxation (group I) and 50 with pseudonormal filling pattern (group II). Another 51 aged-matched healthy persons served as the control group. RESULTS: Patients showed increased left atrial dimensions, atrial wave of the pulmonary vein flow, and Ap, and reduced LV ejection fraction, Ep, and Ep/Ap ratio compared with the control group. Patients in group II revealed increased left atrial dimensions (P =.001), atrial wave of the pulmonary vein flow (P <.001), and Ep/Ap ratio (P <.001), and reduced LV ejection fraction and Ap (P <.001) compared with group I. Regression analysis showed that the strongest independent variable distinguishing normal from pseudonormal filling pattern was the Ep/Ap ratio. CONCLUSION: Ap evaluation offers a new diagnostic diastolic index, especially in the field of the pseudonormal pattern where the separation from normal is difficult.  相似文献   
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One of the major limitations of the use of adenoviruses as gene therapy vectors is the existence of preformed immunity in various populations. Recent studies have linked failure of adenoviral gene therapy trials to the presence of antiadenoviral neutralizing antibodies (NAb). Understanding the distribution and specificity of such antibodies will assist in the design of successful recombinant adenoviral gene therapies and vaccines. To assess the prevalence of NAb to adenovirus serotypes 5 and 35 (Ad5 and Ad35), we analyzed serum samples from adult immunocompetent individuals living in The Gambia, South Africa, and the United States by using a neutralization assay. Serum samples were incubated with A549 lung carcinoma cells and adenoviruses encoding enhanced green or yellow fluorescent proteins; results were analyzed by fluorescence microscopy and flow cytometry. Using this technique, we found a high prevalence of NAb against Ad5 in Gambian, South African, and U.S. subjects at both low and high titers. Conversely, all subjects displayed a low prevalence of NAb to Ad35; when present, anti-Ad35 NAb were seen at low titers. Because of the ability of adenoviruses to elicit systemic and mucosal immune responses, Ad35 with its low NAb prevalence appears to be an attractive candidate vector for gene therapy applications.  相似文献   
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A 32-year-old man was admitted to the emergency department of our hospital after experiencing a peripheral arterial embolism. Investigation of the possible embolic sources in an otherwise asymptomatic patient revealed the existence of a left ventricular diverticulum. The left ventricular diverticulum is a rare congenital anomaly, either isolated or as a part of a syndrome including other congenital malformations. The treatment of choice, especially in symptomatic patients, is surgical resection, while in asymptomatic patients anticoagulation therapy is indicated.  相似文献   
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BACKGROUND AND AIMS: Initiation of a fibrotic process has been suggested as part of the intestinal response to chronic inflammation in inflammatory bowel disease. YKL-40 has been proposed as a new serum marker of fibrosis. We studied compared the serum levels of YKL-40 in patients with ulcerative colitis or Crohn's disease with inflammatory and healthy controls. PATIENTS AND METHODS: YKL-40 serum levels were measured in 179 patients with inflammatory bowel disease (94 ulcerative colitis, 85 Crohn's disease), in 23 with intestinal inflammation of other causes, and 70 matched healthy controls using a commercially available enzyme-linked immunosorbent assay. YKL-40 levels were assessed in terms of disease activity, type and localization. RESULTS: Mean serum YKL-40 levels were 102.6+/-82.7 ng/ml in ulcerative colitis patients and 112.2+/-83.7 ng/ml in Crohn's disease patients, significantly higher than in healthy controls (64.1+/-21.4 ng/ml) but not significantly different from inflammatory controls (77.8+/-23.1 ng/ml). Disease activity and C-reactive protein levels were significantly correlated with YKL-40 levels in both ulcerative colitis and Crohn's disease. Crohn's disease patients with ileum localization had significantly higher YKL-40 levels than those with ileocolonic or colonic disease. Patients with stenotic disease had mean YKL-40 levels not significantly different than those with nonstenotic disease. CONCLUSION: Serum levels of YKL-40 are increased in patients with inflammatory bowel disease, and this is associated with the inflammatory process rather than with the degree of fibrosis.  相似文献   
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Clinical estimation of the combined effect of several risk factors is unreliable and this resulted in the development of a number of risk estimation systems to guide clinical practice. Here, after defining general principles of risk estimation, the authors describe the evolution of the European Society of Cardiology’s (ESC) Systematic COronary Risk Evaluation (SCORE) risk estimation system and some learnings from the data. They move on to describe the establishment of the ESC’s Cardiovascular Risk Collaboration and outline its proposed research directions. First among these is the evolution of SCORE 2, which provides updated, calibrated risk estimates for total cardiovascular events for low, moderate, high, and very high-risk regions of Europe. The authors conclude by considering that the future of risk estimation may be to express risk as years of exposure to a cardiovascular risk factor profile rather than risk over a fixed time period, such as 10 years, and how advances in genetics may permit individualized lifetime risk estimation from childhood on.  相似文献   
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AIMS: Left ventricular (LV) and biventricular (BiV) pacing are potentially superior to right ventricular (RV) apical pacing in patients undergoing atrioventricular (AV) junction ablation and pacing for permanent atrial fibrillation. METHODS AND RESULTS: Prospective randomized, single-blind, 3-month crossover comparison between RV and LV pacing (phase 1) and between RV and BiV pacing (phase 2) performed in 56 patients (70+/-8 years, 34 males) affected by severely symptomatic permanent atrial fibrillation, uncontrolled ventricular rate, or heart failure. Primary endpoints were quality of life and exercise capacity. Compared with RV pacing, the Minnesota Living with Heart Failure Questionnaire (LHFQ) score improved by 2 and 10% with LV and BiV pacing, respectively, the effort dyspnoea item of the Specific Symptom Scale (SSS) changed by 0 and 2%, the Karolinska score by 6 and 14% (P<0.05 for BiV), the New York Heart Association (NYHA) class by 5 and 11% (P<0.05 for BiV), the 6-min walked distance by 12 (+4%) and 4 m (+1%), and the ejection fraction by 5 and 5% (P<0.05 for both). BiV pacing but not LV pacing was slightly better than RV pacing in the subgroup of patients with preserved systolic function and absence of native left bundle branch block. Compared with pre-ablation measures, the Minnesota LHFQ score improved by 37, 39, and 49% during RV, LV, and BiV pacing, respectively, the effort dyspnoea item of the SSS by 25, 25, and 39%, the Karolinska score by 39, 42, and 54%, the NYHA class by 21, 25, and 30%, the 6-min walking distance by 35 (12%), 47 (16%), and 51 m (19%) and the ejection fraction by 5, 10, and 10% (all differences P<0.05). CONCLUSIONS: Rhythm regularization achieved with AV-junction ablation improved quality of life and exercise capacity with all modes of pacing. LV and BiV pacing provided modest or no additional favourable effect compared with RV pacing.  相似文献   
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AIMS: The association between stress-induced ST elevation and functional recovery following revascularization after myocardial infarction remains unclear. We assessed the relative accuracy of dobutamine- and exercise-induced ST elevation in Q wave leads in predicting functional recovery following revascularization, and we investigated the relationship of ST elevation to different wall motion responses to dobutamine. METHODS AND RESULTS: Thirty-nine patients underwent dobutamine stress echo and exercise test 8+/-2 days after Q wave myocardial infarction. All patients underwent angiography and subsequent revascularization. Follow-up echocardiograms were obtained 7+/-4 weeks after revascularization. Functional recovery was assessed by the difference between the baseline and the follow-up asynergy index. Nineteen patients (48%) developed dobutamine- and exercise-induced ST elevation. There was significant agreement between the tests (k=0.58, P<0.001). We found a significant correlation between dobutamine and exercise-induced ST elevation with functional recovery following revascularization (r=0. 45, P<0.005 and r=0.7, P<0.001, respectively). The parameters with the highest predictive value for functional recovery were: (a) the biphasic response during dobutamine infusion, (b) the development of ST elevation in both tests, and (c) the development of exercise-induced ST elevation in more than three leads. CONCLUSION: There is a strong association between dobutamine- and exercise-induced ST elevation with functional recovery following revascularization. Exercise-induced ST elevation in more than three leads and a biphasic response during dobutamine infusion accurately predict functional recovery.  相似文献   
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