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BACKGROUND: Combined multichannel intraluminal impedance and esophageal manometry (MII-EM) is a clinically available tool that assesses the functional defect of various manometric abnormalities. The aim of our study was to evaluate esophageal bolus transit in patients with manometrically defined distal esophageal spasm (DES). METHODS: Patients referred for esophageal function testing underwent combined MII-EM studies including 10 liquid and 10 viscous swallows. Individual swallows were classified using previously published manometric and impedance criteria. DES is traditionally defined as > or =20% simultaneous contractions in the distal esophagus. Diagnosis of esophageal transit abnormalities was defined by the presence of > or =30% incomplete liquid or > or =40% incomplete viscous swallows. RESULTS: Data from 71 patients (43 female, mean age 57 yr, range 16-85) with a manometric diagnosis of DES were analyzed. During liquid swallows, patients with chest pain had higher (p < 0.05) distal esophageal amplitudes (202.3 +/- 34.5 mmHg) and a higher (p < 0.05) percentage of swallows with complete bolus transit (89%+/- 3%) compared to patients presenting with dysphagia (amplitude 117.8 +/- 8.7 mmHg; percentage of complete transit 69%+/- 5%) and patients with reflux symptoms (amplitude 116.4 +/- 12.7 mmHg; percentage of complete transit 74%+/- 5%). Fifty-one percent of the DES patients had a normal bolus transit for liquid and viscous, 24% abnormal bolus transit for one substance, and 25% abnormal bolus transit for liquid and viscous. CONCLUSION: Pressure and bolus transit information in patients with manometrically defined DES points toward heterogenicity of this group of patients. Outcomes data are warranted to evaluate whether stratifying DES patients based on pressure and bolus transit information may improve the clinical approach.  相似文献   
103.

Purpose

B-type natriuretic peptide is one of the most sensitive and specific biohumoral markers of heart failure. We hypothesized that B-type natriuretic peptide changes during treatment of heart failure may provide independent information on disease progression and outcome in patients enrolled in the Val-HeFT trial.

Methods

Patients were divided into four groups according to concentrations of B-type natriuretic peptide at baseline versus 4 months (n = 3740) or 12 months (n = 3343), with respect to the baseline median (97 pg/mL): low→low (stable below median, 44%-46%), high→high (stable above median, 32%-37%), high→low (above to below median, 12%-14%), and low→high (below to above median, 6%-9%). Cox multivariate regression analysis was used to assess the risk of death and morbidity, with adjustment for baseline B-type natriuretic peptide concentrations.

Results

Patients who improved their B-type natriuretic peptide at 4 months (high→low) had a similar risk for mortality (hazard ratio = 1.191, 95% confidence interval [CI] 0.870-1.631, P =.2746) compared with the low→low patients. Conversely, patients who worsened in their B-type natriuretic peptide (low→high) had a risk for mortality (hazard ratio 2.578, CI, 1.861-3.571, P <.0001) higher than patients in the low→low group, and indistinguishable from the high→high group. Worsening of B-type natriuretic peptide (low→high) was associated with 0.03 cm/m2 increase in left ventricular end-diastolic diameter, whereas it decreased by 0.10 cm/m2 in high→low and low→low groups (P <.001).

Conclusions

Changes in B-type natriuretic peptide over time with respect to a threshold value of 97 pg/mL convey an independent and additional prognostic value compared with a single determination of B-type natriuretic peptide in a large population of patients with chronic symptomatic heart failure and might be helpful in the management of these patients.  相似文献   
104.
BACKGROUND: Almost 40% of patients with heart failure (HF) have preserved left ventricular (LV) ejection fraction (EF) and prognosis similar to those with reduced EF. Data on prognostic markers in such patients are limited. We analyzed the prevalence and prognostic value of left atrial (LA) size in this condition. METHODS: 89 normal subjects (Group I), 38 asymptomatic hypertensive patients (Group II) and 183 HF patients with preserved EF (EF >45%) (Group III) were studied. LA diameter (LAD), LV diastolic (LVD) and systolic (LVS) dimensions and mass (LVmass) and EF were measured. E and A wave velocities and E/A were measured. The primary end point was all cause mortality in group III patients. RESULTS: Groups did not differ in age, gender or EF. Group III patients had larger LAD (4.6+-1.0 cm) compared with both Group I (3.7+/-0.6) and Group II (3.7+/-0.5 cm) (p<0.0001). A markedly enlarged (arbitrarily defined as LAD higher or equal 5 cm) had an odds ratio of 34 (95% CI 8-144) in distinguishing HF patients from normals. After a mean follow-up period of 29+/-27 months, 40 patients (21.9%) died. In Cox univariate analysis, NYHA class (HR 2.8 95% C.I. 1.8-4.3; p<0.0001), diastolic blood pressure (DBP) (HR 0.92 95% C.I. 0.88-0.96; p<0.0001), age (HR 1.059 95% C.I. 1.01-1.11; p=0.02) and LAD (HR 1.72 95% C.I. 1.27-2.3; p=0.0005) were predictors of mortality. LAD predicted survival independently of other variables. CONCLUSION: The left atrium is frequently dilated in HF patients compared with controls despite similar EF. LAD showed powerful prognostic value independent of clinical variables.  相似文献   
105.
ABSTRACT

Introduction: Seabuckthorn (SBT) has received worldwide attention for therapeutic, nutraceutical and cosmetic purposes. It is used for the treatment of a number of diseases. Hundreds of commercial products containing SBT are available in the market.

Areas covered: This review article covers patents on the therapeutic potential of SBT and its chemical constituents. The therapeutic areas covered in this review include cancer, cardiovascular, diabetes, inflammation, anti-oxidant, and anti-microbial. The patents were searched through Sci-finder, Espacenet, Google Patent, and US Patent.

Expert opinion: Plant-based drugs have played an important role in the modern drug industry. Since ancient times, SBT has been used to cure several ailments. SBT has emerged as an important plant, which has been investigated for numerous pharmacological properties and shown to be beneficial in a number of therapeutic areas. Several clinical trials have demonstrated the therapeutic potential of SBT for the treatment of many diseases including cardiovascular, inflammation, diabetes, platelet inhibition, etc. There is huge potential for developing standardized herbal products from different parts of SBT.  相似文献   
106.
Percutaneous coronary revascularization was introduced over 30 years ago by Dr Andreas Grüntzig. This event catapulted adult invasive cardiology from a diagnostic entity to a therapeutic modality, which has since become the most frequently performed coronary revascularization procedure worldwide. This success has been built on several key concepts—problem identification, targeted solutions, applied technology, populations-based testing, postmarket surveillance, and education. These concepts will continue to be of paramount importance as novel percutaneous innovations and strategies are brought to bear on an increasingly broader group of patients with cardiovascular disease. In this review, we trace the history, review current practices, and also provide insight into future potential innovations, as it pertains to percutaneous coronary revascularization.  相似文献   
107.
The corpus callosum is the largest white matter tract, important for interhemispheric communication. The aim of this study was to investigate and compare corpus callosum size, shape and diffusion characteristics in 106 very preterm infants and 22 full-term infants. Structural and diffusion magnetic resonance images were obtained at term equivalent. The corpus callosum was segmented, cross-sectional areas were calculated, and shape was analyzed. Fractional anisotropy, mean, axial and radial diffusivity measures were obtained from within the corpus callosum, with additional probabilistic tractography analysis. Very preterm infants had significantly reduced callosal cross-sectional area compared with term infants (p=0.004), particularly for the mid-body and posterior sub-regions. Very preterm callosi were more circular (p=0.01). Fractional anisotropy was lower (p=0.007) and mean (p=0.006) and radial (p=0.001) diffusivity values were higher in very preterm infants' callosi, particularly at the anterior and posterior ends. The volume of tracts originating from the corpus callosum was reduced in very preterm infants (p=0.001), particularly for anterior mid-body (p=0.01) and isthmus tracts (p=0.04). This study characterizes callosal size, shape and diffusion in typically developing infants at term equivalent age, and reports macrostructural and microstructural abnormalities as a result of prematurity.  相似文献   
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