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41.

Objective

To compare the clinical utility of the different imaging techniques used for the evaluation of tracheobronchial diseases.

Materials and Methods

Forty-one patients with tracheobronchial diseases [tuberculosis (n = 18), bronchogenic carcinoma (n = 10), congenital abnormality (n = 3), post-operative stenosis (n = 2), and others (n = 8)] underwent chest radiography and spiral CT. Two sets of scan data were obtained: one from routine thick-section axial images and the other from thin-section axial images. Multiplanar reconstruction (MPR) and shaded surface display (SSD) images were obtained from thin-section data. Applying a 5-point scale, two observers compared chest radiography, routine CT, thin-section spiral CT, MPR and SSD imaging with regard to the detection, localization, extent, and characterization of a lesion, information on its relationship with adjacent structures, and overall information.

Results

SSD images were the most informative with regard to the detection (3.95±0.31), localization (3.95±0.22) and extent of a lesion (3.85±0.42), and overall information (3.83±0.44), while thin-section spiral CT scans provided most information regarding its relationship with adjacent structures (3.56±0.50) and characterization of the lesion (3.51±0.61).

Conclusion

SSD images and thin-section spiral CT scans can provide valuable information for the evaluation of tracheobronchial disease.  相似文献   
42.
目的帮助医生进行诊断、术前预测和实际手术操作,提出一种三维重建、测量的方法。方法利用直肠癌患者的CT扫描结果建立骨盆三维模型,回顾性分析97例中低位直肠癌患者的影像资料,最后进行统计学分析。结果经过对测量数据进行多因素分析,找出几组影响中低位直肠癌保肛手术关键性的解剖限制性因素。结论应用骨盆三维模型可以获得传统骨盆测量学没有提出的解剖径线和空间测量数据,能更加客观地评价骨盆的解剖因素对保肛手术乃至盆腔手术的限制性作用。  相似文献   
43.
In order to clarify the complete cytomorphology of cytopathic changes as a consequence of human papillomavirus (HPV) infection, we performed three-dimensional (3D) reconstruction from confocal fluorescent images. After confirming 22 HPV types using a DNA chip, we performed 3D confocal image restoration in human uterine cervical swab samples and corresponding tumor tissues. On restoration of 3D confocal images, the multinucleated feature of koilocytes was revealed to be multilobation of a single nucleus, as opposed to true multinucleation.  相似文献   
44.
[目的]评价多层螺旋CT(MSCT)三维血管成像技术及其在肾动脉相关性疾病中的临床应用价值。[方法]回顾性分析39例肾动脉相关性疾病病人的MSCT造影增强检查,使用GELightspeed Ultra16排CT进行螺旋薄层扫描,扫描条件:层厚1.25mm,螺距1.75:l,转速0.5s,120KV,350~400MA,扫描总时间10~15S。造影剂总量80~100mL,注药速度3.5-4mL/s。在独立工作站上进行三维肾动脉重建,使用不同的旋转轴观察肾动脉的空间解剖细节及其与肿瘤性病变的关系。[结果]全部病例三维肾动脉血管图像能充分显示肾动脉的空间关系与解剖细节,为肾动脉性疾病与畸形病人做出明确诊断,而且能准确、直观地观察肾动脉与肾肿瘤的空间解剖关系,为手术提供较好的术前评价。其中空间结构显示VR最佳,狭窄测量及血管腔内观察2D-MIP最佳。[结论]MSCT三维肾动脉成像能够准确、直观的显示肾动脉的立体解剖特点,为肾动脉相关性疾病的在诊断与治疗提供重要依据。  相似文献   
45.
The aromatization of testosterone into oestrogens plays a key role in the control of many behavioural and physiological aspects of reproduction. In the quail preoptic area (POA), aromatase activity and the number of aromatase-immunoreactive (ARO-ir) cells are sexually differentiated (males > females). This sex difference is implicated in the control of the sexually dimorphic behavioural response of quail to testosterone. We analysed the ontogenetic development of this sex difference by measuring aromatase activity and counting ARO-ir cells in the POA of males and females from day 1 post hatch to sexual maturity. We investigated in parallel another enzyme: tyrosine hydroxylase, the rate limiting step in catecholamine synthesis. Between hatching and 4 weeks of age, aromatase activity levels were low and equal in males and females. Aromatase activity then markedly increased in both sexes when subjects initiated their sexual maturation but this increase was more pronounced in males so that a marked difference in aromatase activity was present in 6 and 8 week-old subjects. Tyrosine hydroxylase activity progressively increased with age starting immediately after hatching and there was no abrupt modification in the slope of this increase when birds became sexually mature. No sex difference was detected in the activity of this enzyme. The number of ARO-ir cells in the POA progressively increased with age starting at hatching. No sex difference in ARO-ir cell numbers could be detected before subjects reached full sexual maturity. The analysis of the three-dimensional organization of ARO-ir cells in the POA revealed that, with increasing ages, ARO-ir cells acquire a progressively more lateral position: they are largely periventricular in young birds but they are found at higher density in the lateral part of the medial preoptic nucleus in adults. These data indicate that aromatase activity differentiates sexually when birds reach sexual maturity presumably under the activating effects of the increased testosterone levels in males. The number of ARO-ir cells, however, begins to increase in a non sexually differentiated manner before the rise in plasma testosterone in parallel with the increased tyrosine hydroxylase activity. Whether this temporal coincidence results from a general ontogenetic pattern or from more direct causal links remains to be established.  相似文献   
46.
三维打印技术在药剂学中的应用   总被引:4,自引:1,他引:4  
检索分析现有各类文献资料,并进行综合、整理与归纳,系统地介绍三维打印技术及其在缓控释给药装置研究和开发中的应用.由于三维打印技术的实用性、灵活性和有效性,在药剂学领域将有广泛的应用前景.  相似文献   
47.
由创伤或其他病因引起的关节软骨病变通常难以自愈,且目前临床上的治疗方法疗效欠佳。脂肪干细胞 (adipose derived stem cells,ADSCs)是一种来自脂肪组织、具有多向分化潜能的干细胞,基于ADSCs成软骨分化能力的 组织工程学疗法为关节软骨缺损的修复再生提供了新的思路。体外诱导ADSCs分化成软骨的方法主要是采用生长因 子和支架材料模拟体内微环境,进而促进ADSCs向软骨细胞分化,其相关应用已取得初步成功。  相似文献   
48.
为探讨实时三维超声心动图(RT-3DE)定量评估心梗患者经皮冠状动脉介入治疗(PCI)术前后左室收缩功能及同步性参数的变化,选取100例接受PCI治疗的心肌梗死患者和100例正常对照组,应用RT-3DE技术对正常对照组和心梗患者PCI术前及术后1个月测量左心室收缩功能及同步性参数并进行比较。心梗患者PCI术前组左心室各功能参数值均劣于正常对照组,而术后1个月左心室各参数值均较术前明显改善。PCI术前、术后应用RT-3DE能够准确定位、定量反映左心室收缩功能及运动同步性,对心肌梗死的临床诊断及疗效评估具有重要价值。  相似文献   
49.
Technical difficulties, poor image quality and reliance on pattern identifications represent some of the drawbacks of two-dimensional ultrasound imaging of spinal bone anatomy. To overcome these limitations, this study sought to develop real-time volumetric imaging of the spine using a portable handheld device. The device measured 19.2?cm?×?9.2?cm?×?9.0?cm and imaged at 5?MHz centre frequency. 2D imaging under conventional ultrasound and volumetric (3D) imaging in real time was achieved and verified by inspection using a custom spine phantom. Further device performance was assessed and revealed a 75-min battery life and an average frame rate of 17.7?Hz in volumetric imaging mode. The results suggest that real-time volumetric imaging of the spine is a feasible technique for more intuitive visualization of the spine. These results may have important ramifications for a large array of neuraxial procedures.  相似文献   
50.
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