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81.
Thyroid hormone (TH) receptors are present in the myocardium and vascular tissue, and minor alterations in TH concentration can affect cardiovascular (CV) physiology. The potential mechanisms that link CV disease with thyroid dysfunction are endothelial dysfunction, changes in blood pressure, myocardial systolic and diastolic dysfunction, and dyslipidemia. In addition, cardiac disease itself may lead to alterations in TH concentrations (notably, low triiodothyronine syndrome) that are associated with higher morbidity and mortality. Experimental data and small clinical trials have suggested a beneficial role of TH in ameliorating CV disease. The aim of this review is to provide clinicians dealing with CV conditions with an overview of the current knowledge of TH perturbations in CV disease.  相似文献   
82.

Background

Electrical storm (ES), characterized by unrelenting recurrences of ventricular arrhythmias, is observed in approximately 30% of patients with implantable cardioverter-defibrillators (ICDs) and is associated with high mortality rates.

Objectives

Sympathetic blockade with β-blockers, usually in combination with intravenous (IV) amiodarone, have proved highly effective in the suppression of ES. In this study, we compared the efficacy of a nonselective β-blocker (propranolol) versus a β1-selective blocker (metoprolol) in the management of ES.

Methods

Between 2011 and 2016, 60 ICD patients (45 men, mean age 65.0 ± 8.5 years) with ES developed within 24 h from admission were randomly assigned to therapy with either propranolol (160 mg/24 h, Group A) or metoprolol (200 mg/24 h, Group B), combined with IV amiodarone for 48 h.

Results

Patients under propranolol therapy in comparison with metoprolol-treated individuals presented a 2.67 times decreased incidence rate (incidence rate ratio: 0.375; 95% confidence interval: 0.207 to 0.678; p = 0.001) of ventricular arrhythmic events (tachycardia or fibrillation) and a 2.34 times decreased rate of ICD discharges (incidence rate ratio: 0.428; 95% CI: 0.227 to 0.892; p = 0.004) during the intensive care unit (ICU) stay, after adjusting for age, sex, ejection fraction, New York Heart Association functional class, heart failure type, arrhythmia type, and arrhythmic events before ICU admission. At the end of the first 24-h treatment period, 27 of 30 (90.0%) patients in group A, while only 16 of 30 (53.3%) patients in group B were free of arrhythmic events (p = 0.03). The termination of arrhythmic events was 77.5% less likely in Group B compared with Group A (hazard ratio: 0.225; 95% CI: 0.112 to 0.453; p < 0.001). Time to arrhythmia termination and length of hospital stay were significantly shorter in the propranolol group (p < 0.05 for both).

Conclusions

The combination of IV amiodarone and oral propranolol is safe, effective, and superior to the combination of IV amiodarone and oral metoprolol in the management of ES in ICD patients.  相似文献   
83.
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85.
Compromised sleep and increased sympathetic nervous system (SNS) activity are implicated in the pathogenesis of, and disparities in, cardiovascular disease. Parasympathetic dominance during sleep may be important for cardiovascular health. Sleep and autonomic balance influence immune activity, which impacts atherogenesis. We evaluated relationships between autonomic balance during sleep and morning levels of the immune activating cytokines, C‐reactive protein (CRP) and interleukin (IL)‐6. Ninety‐four (59 female) young adult African Americans without medical conditions and substance use disorders spent 2 consecutive nights in a clinical research unit for sleep recordings and blood drawing on awakening. Cardiac tracings from the second sleep recording were analysed for heart rate variability (HRV). Body mass index was the only non‐HRV measure correlated with cytokine levels. Indicators of SNS activity for the presleep, and first non‐rapid eye movement (REM) and REM sleep periods were correlated independently with morning IL‐6 levels. Altered autonomic balance during sleep may be a modifiable factor that influences immune activation.  相似文献   
86.

Objectives

The aim of this study was to develop a new scoring system based on thoracic aortic calcification (TAC) to predict 1-year cardiovascular and all-cause mortality.

Background

A calcified aorta is often associated with poor prognosis after transcatheter aortic valve replacement (TAVR). A risk score encompassing aortic calcification may be valuable in identifying poor TAVR responders.

Methods

The C4CAPRI (4 Cities for Assessing CAlcification PRognostic Impact) multicenter study included a training cohort (1,425 patients treated using TAVR between 2010 and 2014) and a contemporary test cohort (311 patients treated in 2015). TAC was measured by computed tomography pre-TAVR. CAPRI risk scores were based on the linear predictors of Cox models including TAC in addition to comorbidities and demographic, atherosclerotic disease and cardiac function factors. CAPRI scores were constructed and tested in 2 independent cohorts.

Results

Cardiovascular and all-cause mortality at 1 year was 13.0% and 17.9%, respectively, in the training cohort and 8.2% and 11.8% in the test cohort. The inclusion of TAC in the model improved prediction: 1-cm3 increase in TAC was associated with a 6% increase in cardiovascular mortality and a 4% increase in all-cause mortality. The predicted and observed survival probabilities were highly correlated (slopes >0.9 for both cardiovascular and all-cause mortality). The model’s predictive power was fair (AUC 68% [95% confidence interval [CI]: 64% to 72%]) for both cardiovascular and all-cause mortality. The model performed similarly in the training and test cohorts.

Conclusions

The CAPRI score, which combines the TAC variable with classical prognostic factors, is predictive of 1-year cardiovascular and all-cause mortality. Its predictive performance was confirmed in an independent contemporary cohort. CAPRI scores are highly relevant to current practice and strengthen the evidence base for decision making in valvular interventions. Its routine use may help prevent futile procedures.  相似文献   
87.

Background

Patients with gout are at an increased risk of cardiovascular (CV) disease including myocardial infarction (MI), stroke, and heart failure (HF).

Objectives

The authors conducted a cohort study to examine comparative CV safety of the 2 gout treatments—probenecid and allopurinol—in patients with gout.

Methods

Among gout patients ≥65 years of age and enrolled in Medicare (2008 to 2013), those who initiated probenecid or allopurinol were identified. The primary outcome was a composite CV endpoint of hospitalization for MI or stroke. MI, stroke, coronary revascularization, HF, and mortality were assessed separately as secondary outcomes. The authors estimated the incidence rate and hazard ratio of the primary and secondary outcomes in the 1:3 propensity score–matched cohort of probenecid and allopurinol initiators.

Results

A total of 9,722 probenecid initiators propensity score–matched to 29,166 allopurinol initiators with mean age of 76 ± 7 years, and 54% males were included. The incidence rate of the primary composite endpoint of MI or stroke per 100 person-years was 2.36 in probenecid and 2.83 in allopurinol initiators with a hazard ratio of 0.80 (95% confidence interval: 0.69 to 0.93). In the secondary analyses, probenecid was associated with a decreased risk of MI, stroke, HF exacerbation, and mortality versus allopurinol. These results were consistent in the subgroup analyses of patients without baseline CV disease or those without baseline chronic kidney disease.

Conclusions

In this large cohort of 38,888 elderly gout patients, treatment with probenecid appears to be associated with a modestly decreased risk of CV events including MI, stroke, and HF exacerbation compared with allopurinol.  相似文献   
88.

Background

Multi-slice computed tomography (MSCT) allows non-invasive assessment of the coronary arteries and simultaneously can provide measurement of left ventricular ejection fraction (LVEF). The accuracy of newer MSCT generations (64-slice or more) for assessment of LVEF compared with magnetic resonance imaging (MRI) and two-dimensional transthoracic echocardiography (TTE) has not been evaluated in a meta-analysis.

Purpose

To evaluate, via a systematic literature review and meta-analysis, whether MSCT can assess LVEF with high accuracy compared with MRI and TTE.

Methods

Electronic databases and reference lists for relevant published studies were searched. Twenty-seven eligible studies provided mean LVEF% with its standard deviation (SD) measured by MSCT versus MRI and TTE. Meta-analysis of weighted mean difference (WMD) and Bland–Altman method were used to quantify the mean difference and agreement between MSCT compared with MRI and TTE.

Results

The results of combining 12 studies showed no significant difference in LVEF% between MSCT and MRI with a WMD of −0.11 (−1.48, 1.26, 95% CI), p = 0.88. Bland–Altman analysis showed excellent agreement between MSCT and MRI with a bias of 0.0 (−3.7, 3.7 ± 1.96SD) with 95% CI. The results of combining 15 studies showed no significant difference in LVEF between MSCT versus TTE measurements with a WMD of 0.19 (−1.13 to 1.50; 95% CI), p = 0.87. Bland–Altman analysis showed excellent agreement between MSCT and TTE with a bias of 0.3 (−4.7, 5.7 ± 1.96SD) with 95% CI.

Conclusion

The newer MSCT generations can provide accurate LVEF measurement compared to MRI and TTE. MSCT represents a valid technique for the combined evaluation of LVEF and coronary artery disease.  相似文献   
89.

Background

Clinical and ethical issues persist in determining candidacy for advanced heart failure (HF) therapies in elderly patients. Selection takes many factors into account, including “activation” (engagement and ability to self-manage).

Objective

To investigate effects of age, activation, and depression/anxiety on selection and 6-month survival of participants considered for therapy.

Methods

Consecutive people referred for advanced HF therapy completed the Patient Activation Measure and Hospital Anxiety and Depression Scale. We analyzed data from participants by age (≥65 vs. <65 years), stratified by approval for therapy.

Results

Among 168 referred, 109 were approved, with no difference in activation between age groups (88% highly activated). Similarly, activation was not associated with age among those not approved. Activation was related to anxiety in older, approved participants, but not to depression.

Conclusions

Concerns regarding reduced self-management in the elderly may not be valid. Age alone should not disqualify a candidate for advanced HF therapy.  相似文献   
90.
INTRODUCTION AND OBJECTIVES: Measurement of N-terminal pro-B-type natriuretic peptide (NTproBNP) helps in diagnosing heart failure (HF). The test's usefulness may be greatest in patients with severe dyspnea of uncertain origin. However, NTproBNP has not been evaluated specifically in this setting. PATIENTS AND METHOD: This prospective emergency department study included 70 patients with shortness of breath at rest as their chief complaint. In the attending physician's opinion, both HF and a non-cardiac cause were equally probable. Blinded NTproBNP measurement was carried out in blood samples collected on admission. Patients were monitored and their final diagnoses were based on clinical findings, therapeutic responses, and cardiac and noncardiac tests performed during hospitalization. RESULTS: The NTproBNP level was higher in the 49 patients (70%) with a final diagnosis of HF (P = .006); the area under the ROC curve was 0.72 (0.60-0.82). The optimum diagnostic cut-off value was 900 pg/mL, which had an accuracy of 87%, a sensitivity of 98%, and a negative predictive value of 92%. The NTproBNP level was significantly higher in the 6 patients (9%) who died during hospitalization (P = .009); the area under the ROC curve was 0.87 (0.76-0.93) and the optimum cut-off value for predicting death was 5500 pg/mL, which had an accuracy of 77%, a sensitivity of 100%, and a positive likelihood ratio of 4.2. CONCLUSIONS: In patients with severe dyspnea and an uncertain diagnosis of HF, an NTproBNP level < 900 pg/mL helps exclude the presence of HF, whereas a NTproBNP level > 5500 pg/mL identifies patients at an increased risk of death.  相似文献   
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