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101.
目的探讨三维超声评估胆囊功能及胆囊胆汁动力时相的临床意义。方法利用三维超声对50例正常体检者(正常组)和50例胆囊结石患者(胆石组)进行脂餐试验,记录餐前、餐后每隔10 min的胆囊容积,共计380 min,计算胆囊最大收缩率(GBEF_(max))和最大收缩时间(Tmax),并绘制胆囊容积变化曲线图。结果正常组餐前胆囊容积为(16.75±7.14)mL,餐后90 min胆囊容积最小为(1.90±0.98)mL,GBEF_(max)为(88.61±10.39)%,Tmax为(90.34±12.36)min,360 min胆囊容积恢复到餐前水平。与正常组比较,胆石组餐前胆囊体积(19.06±6.93)mL明显增大(P0.05),GBEF_(max)(67.27±7.26)%明显降低(P0.05),Tmax(110.85±10.33)min明显延长,餐后约360 min胆囊容积恢复到餐前水平。依据胆囊胆汁动力相变化,胆囊胆汁排出相为餐后0~90 min,胆囊胆汁充盈相为餐后90~360 min,胆囊胆汁浓缩相为餐后360 min。结论三维超声等影像学只需检测餐前和餐后90 min胆囊容积即可达到评估胆囊功能,胆囊胆汁动力时相的变化可能更全面体现胆囊功能,对临床手术方式及时机的选择有较高实用价值。  相似文献   
102.
103.
Left atrial appendage (LAA) has unique anatomical and physiological properties, which make it a common site for thrombus formation in many cardiovascular and systemic diseases. Assessment of LAA for thrombus thus becomes important in many clinical situations and two-dimensional transesophageal echocardiography (2D TEE), which allows excellent quality images of LAA because of its close proximity to esophagus is routinely used for this purpose. However, it is a semiinvasive procedure, requires more time and involves some degree of patient discomfort. With some training and experience, two-dimensional transthoracic echocardiography (2D TTE) can visualize LAA in most patients with good acoustic windows. A disadvantage of both 2D TTE and 2D TEE is that they provide only a thin slice or section of cardiac structures at any given time limiting their utility in comprehensively assessing the LAA for thrombus. On the other hand, live/real time three-dimensional (3D) TTE overcomes this limitation of both 2D TTE and 2D TEE because of its ability to encompass whole of the LAA in three-dimensions in the acquired data set, which can then be cropped and sectioned systematically at any desired angulation to more definitively look for clot. 3D TTE is also useful in differentiating a clot from pectinate muscles in the LAA, which can mimic a thrombus resulting in patient mismanagement. In addition, 3D TTE is helpful in sectioning a clot for lysis, which has implications in clot resolution. We reviewed the existing literature comparing the relative advantages and disadvantages of 3D TTE versus 2D TEE and found that in patients with good acoustic windows 3D TTE had similar efficacy for detecting LAA thrombus. (Echocardiography 2012;29:112-116)  相似文献   
104.
105.
Accurate determination of left ventricular mass, volume, ejection fraction, and wall motion is important for clinical decision making. Currently, M-mode and two-dimensional echocardiography (2DE) have been routinely used for this purpose. Although these 1D or 2D modalities provide excellent diagnostic and prognostic information, they have a number of technical limitations including the time required to perform the procedure and operator-dependent image acquisitions. In addition, they are inherently limited by geometric assumption of three-dimensional (3D) left ventricular structures based on 2D slices. With the improvement in transducer technology and software development, 3D echocardiography (3DE) has become widely available. Left ventricular quantitation by 3DE has been demonstrated to be accurate by multiple studies that compared 3DE with reference techniques. In addition, 3DE measurements were found to be more reproducible and less variable than 2DE. Real time 3DE imaging has potential advantages in stress echocardiography including rapid acquisition, unlimited number of planes, avoidance of foreshortening, and precise segment matching. This is a major step forward in our diagnostic armamentarium for the evaluation of ischemia. In this review, we summarized the current evidence of 3DE for left ventricular evaluation. (Echocardiography 2012;29:66-75)  相似文献   
106.
We report an adult patient with a left ventricular pseudoaneurysm following an acute myocardial infarction in whom three-dimensional (3-D) transesophageal echocardiography (TEE) delineated clearly not only the location but also the size and shape of the rupture site. The size of the rupture site measured by 3-D TEE correlated well with the surgical measurements. Three-dimensional images also showed a localized superior distortion of the lateral aspect of the mitral annulus and left atrial wall produced by the pseudoaneurysm. The resulting severe mitral regurgitation practically disappeared after repair and decompression of the pseudoaneurysm.  相似文献   
107.
Objective To evaluate the efficacy of the combination of gynecologic imaging reporting and data system (GI-RADS) ultrasonographic stratification and 3D contrast-enhanced ultrasonography (3D-CEUS) in identifying malignant lesions from benign ovarian masses. Methods Both of 2D ultrasound (2D-US) and 3D-CEUS were performed on 102 patients with ovarian masses. The perfusion characteristics of ovarian masses were observed with 3D-CEUS,and the 2D-US features of ovarian masses were analyzed based on GI-RADS. Simple and multiple Logistic regression analysis were used to investigate whether the independent risk predictors in differential diagnosis of benign and malignant ovarian could be confirmed. In addition, ROC curves were drawn. The diagnostic efficacy of GI-RADS combined with 3D-CEUS scoring system was evaluated and compared with that of only GI-RADS. Results Simple and multiple Logistic regression analysis confirmed that there were 8 independent predictors of malignant masses, including large papillary projections (≥ 7 mm), separated or wall thickness ≥ 3 mm, central blood flow, the proportion of solid part ≥ 50%, combination of ascites, high level enhancement, uneven distribution of contrast media in enhanced solid part and the vascular with characteristics as dense, tortuous and anfractuous. When using 4 points as the cut-off, the area under the curve (AUC) of GI-RADS combined with 3D-CEUS scoring system in identifying malignant ovarian masses was 0.969, higher than that of only GI-RADS (0.839; Z=1.64, P=0.029). Furthermore, the scoring system showed higher sensitivity, specificity, positive predictive value, negative predictive value and accuracy (all P<0.001). Conclusion The combination of GI-RADS with 3D-CEUS can be more effective to distinguish malignant lesions from benign ovarian masses.  相似文献   
108.
目的探讨3D全胸腔镜不停跳房间隔缺损(ASD)修补术的学习曲线及安全性。方法 ASD患者206例,完成3D全胸腔镜ASD修补及三尖瓣成形术44例(腔镜组)。累积和(CUSUM)法确定3D胸腔镜ASD修补术的学习曲线。并与传统开胸手术(开胸组)行倾向性评分匹配(PSM),分析腔镜组学习期间手术的安全性。结果 CUSUM学习曲线显示手术失败率、手术时间、体外循环时间、术后并发症发生率分别在第34、21、29及39例患者后低于可接受水平。匹配后两组术前特征不存在系统差异。腔镜组体外循环时间长于开胸组(P=0.000);手术时间、呼吸机辅助时间、ICU住院时间、术后并发症及总住院费用两组比较差异无统计学意义(P0.05)。腔镜组术后引流量明显少于开胸组(P=0.000)。结论 3D胸腔镜不停跳ASD修补术使手术更简化,更安全,不增加术后并发症及住院费用,并能在39例后快速跨越学习曲线。  相似文献   
109.
Patient-specific 3D models obtained by the segmentation of volumetric diagnostic images play an increasingly important role in surgical planning. Surgeons use the virtual models reconstructed through segmentation to plan challenging surgeries. Many solutions exist for the different anatomical districts and surgical interventions. The possibility to bring the 3D virtual reconstructions with native radiological images in the operating room is essential for fostering the use of intraoperative planning. To the best of our knowledge, current DICOM viewers are not able to simultaneously connect to the picture archiving and communication system (PACS) and import 3D models generated by external platforms to allow a straight integration in the operating room. A total of 26 DICOM viewers were evaluated: 22 open source and four commercial. Two DICOM viewers can connect to PACS and import segmentations achieved by other applications: Synapse 3D® by Fujifilm and OsiriX by University of Geneva. We developed a software network that converts diffuse visual tool kit (VTK) format 3D model segmentations, obtained by any software platform, to a DICOM format that can be displayed using OsiriX or Synapse 3D. Both OsiriX and Synapse 3D were suitable for our purposes and had comparable performance. Although Synapse 3D loads native images and segmentations faster, the main benefits of OsiriX are its user-friendly loading of elaborated images and it being both free of charge and open source.  相似文献   
110.
Objectives: To compare two-dimensional with three-dimensional ultrasound evaluation of the fetal nasal bone in the second trimester.

Methods: A prospective, non-interventional study was conducted, in 55 singleton fetuses, between 18 and 24 weeks’ gestation. Fetal nasal bone length was measured in the midsagittal plane by two-dimensional imaging and in the midsagittal and coronal plane with three-dimensional ultrasound. All three measurements were compared with one another using one-way repeated samples-measures ANOVA and paired samples t-test.

Results: The average fetal nasal bone length (mean?±?SD) as determined by the three methods was 7.01?±?0.94?mm for the two-dimensional midsagittal, 6.96?±?1.34?mm for the three-dimensional midsagittal, and 6.98?±?1.32?mm for the three-dimensional coronal plane; comparisons between one another were not statistically significant. Unilateral hypoplasia and bifid shape of the fetal nasal bone were detected in 8.2% and 20.4% of cases, respectively, by three-dimensional ultrasound, whereas all cases evaded detection with two-dimensional ultrasound (p?<?0.001 and p?=?0.001, respectively).

Conclusions: Fetal nasal bone length measured with two-dimensional ultrasound does not differ significantly from three-dimensional measurements. However, three-dimensional ultrasound is superior in detecting unilateral nasal bone hypoplasia or absence and in assessing fetal nasal bone shape. Hence, fetal nasal bone examination in the second trimester should include three-dimensional ultrasound evaluation.  相似文献   

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