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31.
We report a case of a free-floating left atrial thrombus in a patient with severe mitral stenosis diagnosed by cross-sectional echocardiography. The Doppler technique was very useful in explaining some peculiar auscultatory and clinical aspects present in this rare complication of mitral valvar stenosis.  相似文献   
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The aim of this observational study was to identify factors influencing the control of blood pressure (i.e., <140/90 mmHg, or <130/80 mmHg in diabetic patients) and low-density lipoprotein (LDL) cholesterol level (<100 mg/dL) in 1223 patients with cardiovascular disease. Overall, 70.2% of patients were men, and their mean age was 66.4 years. Blood pressure was poorly controlled in 50.9% (95% confidence interval [CI], 46.9%-54.8%) and the LDL cholesterol level was poorly controlled in 60.1% (95% CI, 56.3%-63.9%). Determinants of poor blood pressure control were diabetes, hypertension, no previous diagnosis of heart failure, previous diagnosis of peripheral artery disease or stroke, obesity, and no lipid-lowering treatment. Determinants of poor LDL cholesterol control were no lipid-lowering treatment, no previous diagnosis of ischemic heart disease, no antihypertensive treatment, and dyslipidemia. The factors affecting blood pressure control were different from those affecting LDL cholesterol control, an observation that should be taken into account when implementing treatment recommendations for achieving therapeutic objectives in secondary prevention.  相似文献   
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The vena contracta and effective regurgitant orifice area (EROA) are currently used for the clinical assessment of mitral regurgitation (MR) from 2-D color Doppler imaging. In addition to being highly user dependent and having low repeatability, these methods do not represent accurately the anatomic regurgitant orifice (ARO), which affects the adequate assessment of MR patients. We propose a novel method for semi-automatic detection and quantitative assessment of the 3-D ARO shape from 3-D transesophageal echocardiographic images. The algorithm was tested on a set of 25 patients with MR, and compared with EROA for validation. Results indicate the robustness of the proposed approach, with low variability in relation to different settings of user-defined segmentation parameters. Although EROA and ARO exhibited a good correlation (r = 0.8), relatively large biases were measured, indicating that EROA probably underestimates the real shape and size of the regurgitant orifice. Along with the higher reproducibility of the proposed approach, this highlights the limitations of current clinical approaches and underlines the importance of accurate assessment of the ARO shape for diagnosis and treatment in MR patients.  相似文献   
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We sought to review echocardiographic incidence of anomalous images (AI) as false tendons and trabeculations of the left ventricle (LV) in light of recent advancements in echocardiographic evaluation of heart anatomy. In 1580 patients the presence of false tendons, trabeculations, or thrombi was evaluated with transthoracic echocardiography and correlated to clinical characteristics and echocardiographic parameters. Incidence of AI was 46.7% (75% false tendons, 23% trabeculations, 2% thrombi), slightly higher in pathologic (48.9%) than in normal hearts (40.8%). AI were more frequent in male patients (52%) than in female patients (39.7%) and associated with LV dilatation, hypertrophy, and systolic dysfunction. False tendons and trabeculations were not related to age. Male sex was the most significant independent predictor of AI. In 2 patients, isolated LV noncompaction of myocardium was diagnosed and confirmed by magnetic resonance imaging. This study shows a high prevalence of AI for patients with and without pathologic hearts suggesting the need of updating LV echocardiographic anatomy. It also emphasizes the necessity for an awareness of these anatomic variants when evaluating patients for mural thrombi and cardiomyopathies.  相似文献   
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BACKGROUND: The steroidal aromatase inactivator exemestane has demonstrated activity after prior failure of non-steroidal aromatase inhibitors (including third-generation inhibitors letrozole and anastrozole) in postmenopausal women with advanced breast cancer. If exemestane is used as first anti-aromatase agent, however, it is unclear whether patients can still benefit from letrozole or anastrozole after progression. PATIENTS AND METHODS: Postmenopausal patients with advanced, hormone receptor-positive or -unknown breast cancer were eligible for this study. Patients with no prior exposure to anti-aromatase drugs received exemestane, 25 mg daily, as first anti-aromatase agent. At the time of progression, patients were crossed-over to anastrozole or letrozole if further endocrine therapy was considered appropriate. Patients with prior exposure to anti-aromatase agents were also included in the study, and were given anastrozole or letrozole if they had previously received exemestane, or exemestane if they had previously received anastrozole or letrozole. The primary endpoint of the study was the clinical benefit rate (complete response + partial response + stabilization of disease for >or=24 weeks). RESULTS: Forty patients received exemestane 25 mg daily as first anti-aromatase agent, with a CB rate of 67.5% (95% CI 52.9-82.0%) and a median time to progression (TTP) of 9.6 months. In 18 patients, letrozole (n = 17) or anastrozole (n = 1) were used after failure of exemestane: the CB rate was 55.6% (95% CI 32.6-78.5%) with a median TTP of 9.3 months. In 23 patients, exemestane was used after failure of letrozole or anastrozole: the CB rate was 43.5% (95% CI 23.2-63.7%) with a median TTP of 5.1 months. CONCLUSIONS: Our study confirms that exemestane is active after prior failure of letrozole or anastrozole. We have also shown that patients can receive exemestane as their first anti-aromatase agent and still benefit from letrozole or anastrozole after progression. This suggests that the partial non-cross resistance between steroidal and non-steroidal anti-aromatase agents is independent of the sequence employed.  相似文献   
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In this study, the potential of lecithin/chitosan nanoparticles (NPs) as colloidal nanosystem for transdermal melatonin delivery was investigated. Mean diameter and zeta-potential of NPs differing in lecithin type (Lipoid S45 and S100) and chitosan content ranged between 113.7 and 331.5?nm and 4.6 and 31.2?mV, respectively. Melatonin loadings were up to 7.2%. The potential of lecithin/chitosan NPs to enhance transdermal melatonin delivery was investigated by determining the drug flux across dermatomed porcine skin and its skin deposition. Lecithin/chitosan NPs provided 1.3-2.3-fold higher flux compared to melatonin solution. The highest flux, 9.0?±?0.21?μg/cm2/h, was observed for S45 lecithin/chitosan NPs with lecithin/chitosan weight ratio of 20:1. NP possible cytotoxicity in vitro was evaluated using human skin keratinocytes and fibroblasts. It was demonstrated that lecithin/chitosan NPs can be applied to skin cells at concentrations up to 200?μg/mL without inducing plasma membrane damage or cell viability decrease.  相似文献   
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