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71.
目的:研究核磁共振扫描和超声诊断子宫腺肌症的价值。方法按照随机分号法将该院2013年1月-2014年12月间诊治的100例子宫腺肌症患者均分为两组,对单号组患者进行核磁共振扫描(观察组),对双号组患者进行超声诊断(对照组),对比观察二者的临床诊断价值。结果观察组患者的诊断准确率、误诊率及漏诊率分别为74.00%、16.00%、10.00%,对照组患者分别为56.00%、20.00%、24.00%,前者均优于后者,差异有统计学意义(P<0.05);在患者满意度方面,观察组为98.00%,明显高于对照组患者的86.00%,差异有统计学意义(P<0.05)。结论核磁共振扫描与超声诊断子宫腺肌症均具有重要价值,但前者的诊断准确率较高,误诊率和漏诊率均低于后者,且患者满意度较高,值得临床推广使用。  相似文献   
72.

Objective:

The aim was to compare 2 disposable insulin pens, FlexTouch® (Novo Nordisk, insulin aspart) and SoloSTAR® (Sanofi, insulin glulisine), according to new ISO 11608-1:2012 requirements for dosing accuracy.

Methods:

Sixty pens of each type were tested at 1, 40, and 80 U doses. Following the new ISO requirements, each dose was delivered from the front, middle, and rear one-third of the pen. Statistical analysis was performed using Student’s t test.

Results:

Both pens delivered all doses within ISO limits. The difference between the average measured dose and the target dose was significantly smaller for SoloSTAR than FlexTouch at 40 U (P = .009) and 80 U (P = .008), but not at 1 U (P = .417).

Conclusion:

Both insulin pens fulfilled the dosing accuracy requirements defined by ISO 11608-1:2012 at all 3 dosage levels.  相似文献   
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目的:探讨射波刀治疗床可修正值与六维颅骨(6D Skull)靶区追踪总体精度的关系.方法:通过影像引导将治疗床移至所需修正位置进行6D Skull球方模型定位精度测试,将测试结果与修正值为0相比较及分析.结果:治疗床3个平移方向修正值为0、3、6、10 mm,靶区追踪总体精度分别为0.23、0.32、0.53、0.55 mm;治疗床3个旋转方向修正值为(0.3、0.3、1°)、(0.6、0.6、2.)、(1、1、3°),靶区追踪总体精度分别为0.12、0.99、0.78 mm;治疗床3个平移方向和3个旋转方向修正值为(3、3、3 mm,0.3、0.3、1°)、(6、6、6mm,0.6、0.6、2°)、(10、10、10 mm,1、1、3°),靶区追踪总体精度分别为0.08、0.8、1.4 mm.结论:射波刀6D Skull靶区追踪总体精度随着治疗床3个平移方向或(和)3个旋转方向修正值的增加而增大,日常治疗摆位时应尽可能地减小治疗床的修正值.  相似文献   
78.
BackgroundCarotid and femoral plaque burden is a recognized biomarker of cardiovascular disease risk. A new electronic-sweep 3-dimensional (3D)–matrix transducer method can improve the functionality and image quality of vascular ultrasound atherosclerosis imaging.ObjectivesThis study aimed to validate this method for plaque volume measurement in early and intermediate–advanced plaques in the carotid and femoral territories.MethodsPlaque volumes were measured ex vivo in pig carotid and femoral artery specimens by 3-dimensional vascular ultrasound (3DVUS) using a 3D-matrix (electronic-sweep) transducer and its associated 3D plaque quantification software, and were compared with gold-standard histology. To test the clinical feasibility and accuracy of the 3D-matrix transducer, an experiment was conducted in intermediate–high risk individuals with carotid and femoral atherosclerosis. The results were compared with those obtained using the previously validated mechanical-sweep 3D transducer and established 2-dimensional (2D)–based plaque quantification software.ResultsIn the ex vivo study, the authors assessed 19 atherosclerotic plaques (plaque volume, 0.76 µL-56.30 μL), finding strong agreement between measurements with the 3D-matrix transducer and the histological gold-standard (intraclass correlation coefficient [ICC]: 0.992; [95% CI: 0.978-0.997]). In the clinical analysis of 20 patients (mean age 74.6 ± 4.45 years; 40% men), the authors found 64 (36 carotid and 28 femoral) of 80 scanned territories with atherosclerosis (measured atherosclerotic volume, 10 μL-859 μL). There was strong agreement between measurements made from electronic-sweep and mechanical-sweep 3DVUS transducers (ICC: 0.997 [95% CI: 0.995-0.998]). Agreement was also high between plaque volumes estimated by the 2D and 3D plaque quantification software applications (ICC: 0.999 [95% CI: 0.998-0.999]). Analysis time was significantly shorter with the 3D plaque quantification software than with the 2D multislice approach with a mean time reduction of 46%.Conclusions3DVUS using new matrix transducer technology, together with improved 3D plaque quantification software, simplifies the accurate volume measurement of early (small) and intermediate–advanced plaques located in carotid and femoral arteries.  相似文献   
79.

Objectives

This study sought to compare the diagnostic accuracy of visual and quantitative analyses of myocardial perfusion cardiovascular magnetic resonance against a reference standard of quantitative coronary angiography.

Background

Visual analysis of perfusion cardiovascular magnetic resonance studies for assessing myocardial perfusion has been shown to have high diagnostic accuracy for coronary artery disease. However, only a few small studies have assessed the diagnostic accuracy of quantitative myocardial perfusion.

Methods

This retrospective study included 128 patients randomly selected from the CE-MARC (Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease) study population such that the distribution of risk factors and disease status was proportionate to the full population. Visual analysis results of cardiovascular magnetic resonance perfusion images, by consensus of 2 expert readers, were taken from the original study reports. Quantitative myocardial blood flow estimates were obtained using Fermi-constrained deconvolution. The reference standard for myocardial ischemia was a quantitative coronary x-ray angiogram stenosis severity of ≥70% diameter in any coronary artery of >2 mm diameter, or ≥50% in the left main stem. Diagnostic performance was calculated using receiver-operating characteristic curve analysis.

Results

The area under the curve for visual analysis was 0.88 (95% confidence interval: 0.81 to 0.95) with a sensitivity of 81.0% (95% confidence interval: 69.1% to 92.8%) and specificity of 86.0% (95% confidence interval: 78.7% to 93.4%). For quantitative stress myocardial blood flow the area under the curve was 0.89 (95% confidence interval: 0.83 to 0.96) with a sensitivity of 87.5% (95% confidence interval: 77.3% to 97.7%) and specificity of 84.5% (95% confidence interval: 76.8% to 92.3%). There was no statistically significant difference between the diagnostic performance of quantitative and visual analyses (p = 0.72). Incorporating rest myocardial blood flow values to generate a myocardial perfusion reserve did not significantly increase the quantitative analysis area under the curve (p = 0.79).

Conclusions

Quantitative perfusion has a high diagnostic accuracy for detecting coronary artery disease but is not superior to visual analysis. The incorporation of rest perfusion imaging does not improve diagnostic accuracy in quantitative perfusion analysis.  相似文献   
80.
Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy among other endocrine tumors, and BRAF V600E is a frequent genetic mutation occurring in the disease. Although different molecular techniques, most importantly sequencing has been widely recognized as a gold standard but molecular diagnosis remains an expensive, laborious, and time‐intensive process. Recently, immunohistochemistry (IHC) with anti‐BRAF V600E (VE1) antibody has increased practical utility and implemented clinically for the detection of BRAF V600E mutation. Therefore, the study aimed to evaluate diagnostic accuracy of VE1 IHC for detecting the BRAF V600E mutation frequency and clinical implementation in diagnostic laboratories. In this study, 72 formalin fixed paraffin‐embedded tissues (FFPE) were used to determine the BRAF V600E mutation status using IHC and Sanger sequencing. The mutation was found in 29% and 28% cases using IHC and Sanger sequencing, respectively. Furthermore, the results showed 100% sensitivity, 98.07% specificity, 95.2% positive predictive value, and 100% negative predictive value. Notably, significant associations were found between BRAF V600E status and tumor stage, tumor focality, and extrathyroidal extensions, respectively. VE1 IHC was found to be a highly sensitive, specific, and diagnostically accurate method in this cohort. Therefore, BRAF V600E detection through IHC has been considered as the best tailored technique for routine pathology laboratories.  相似文献   
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