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1.
INTRODUCTION: A 16-year-old Arab boy had suffered from a severe head injury including an intracranial haematoma. Despite replantation of the bone flap later on, the cosmetic result was very unfavourable due to partial resorption of the reinserted bone and atrophy of the right temporalis muscle. AIM: For contour reconstruction of both soft and hard tissues the boy was transferred from Saudi Arabia. METHOD: A spiral CT was obtained and the contour was reconstructed using a new algorithm for surface generation. RESULT: The resulting titanium implant was inserted without complications or the need for revision. The cosmetic result was good and corresponded to the preoperative digital planning. CONCLUSION: Techniques of computer-assisted implant prefabrication and surgery may include special algorithms for considering soft tissues including contour deficits of the temporalis muscle.  相似文献   
2.

Objective

To investigate the expression of antigen processing-1 (Tap-1) and Tapasin in oral squamous cell carcinoma (OSCC), and observe the immune response against OSCC by use of IFN-γ-antigen induced dendritic cells (DCs) in vitro and in vivo.

Design

Expression of Tap-1 and Tapasin in different cell lines was analysed. CAL27 cells were treated with IFN-γ. Antigen from the treated cells was presented by DCs. Pulsed DC was then co-cultivated with CD8+ T lymphocyte to induce antigen specific cytotoxic lymphocytes (CTLs). The immune response elicited by CTLs against OSCC was observed.

Results

A significant lower expression of Tap-1 and Tapasin was observed in OSCC cell lines. IFN-γ exerted time-dependent effect for increasing the expression of these genes. Antigen from the treated CAL27 cells was presented by DCs. CTLs were induced and generated a strong immune response in vitro and in vivo.

Conclusions

Tap-1 and Tapasin were downregulated in OSCC. IFN-γ increased the expression of these genes. Use of IFN-γ-antigen induced DCs could induce stronger immune response in vitro and in vivo.  相似文献   
3.
The aim of this study was to compare detection of non-cavitated approximal caries lesions in images from seven solid-state intraoral digital receptors, with particular focus on two task-specific enhancement filters. One hundred and sixty approximal non-cavitated surfaces were radiographed under standardized conditions using the following seven intraoral solid-state digital receptors: two CMOS systems, Schick CDR-APS, and Kodak RVGui; and five CCD systems: Visualix, VistaRay, Dixi2, Sidexis, and Dr. Suni Plus. The Kodak RVGui digital images were captured with two task-specific, predefined enhancement filters ("dento-enamel" and "periodontal"). Eight observers examined the digital images for the presence or absence of approximal carious lesions. The teeth were subsequently sectioned for histological analysis, which served as the "gold standard" for the radiographic examination and allowed for a calculation of sensitivity, specificity, and overall accuracy. Both RVG modalities obtained the highest sensitivity values, which were significantly higher than with Visualix, Sidexis, and VistaRay images (all P 0.05).  相似文献   
4.
5.
目的 分析颌面部巨大血管畸形的临床特点及治疗方法,探讨放疗在血管畸形治疗中的可行性.方法 回顾分析2000年1月至2008年1月浙江大学医学院附属第二医院施行三维立体定向适形放射治疗的颌面部巨大血管畸形6例的临床资料,并主要根据影像检查与临床体检结果判断疗效.结果 6例患者在术中、术后无严重并发症,均对治疗后面部外形满意,MRI示病变范围缩小,甚至消失.随访0.5~9年,6例患者均无明显复发迹象.无一例出现视器损伤、张口受限等放疗并发症.结论 三维立体定向适形放疗可以作为一种安全有效治疗颌面部巨大血管畸形的方法.
Abstract:
Objective To discuss the clinical use of radiotherapy in the treatment of giant vascular malformation. Methods Six patients with giant vascular malformation in oral and maxillofacial region were treated by three dimensional radiation therapy in Department of Stomatology, The Second Affiliated Hospital,School of Medicne, Zhejiang University in the last ten years and the cilinical data were reviewed. The treatment results were evaluated by clinical examination and radiology. Results No complication was observed during and after the radiotherapy. All patients were satisfied with the aesthetic results. The lesions in MRI were all reduced and even disappeared. There was no sign of recurrence during the follow-up period.Conclusions Three dimensional radiotherapy is safe and effective for oral and maxillofical vascular malformation.  相似文献   
6.
It is of clinical interest to record the amplitudes of temporomandibular joint (TMJ) sounds. The aim was to test the hypothesis that sealing the meatus, when placing a microphone in the ear canal affects such recording by increasing the sound pressure level (SPL). Bilateral recordings of 249 TMJ clickings were made from three subjects, using sampling rates of 48 or 96 kHz and 24 bits A/D conversion, with and without the ear canals sealed by Silicone putty. The peak-to-peak equivalent sound pressure level (peSPL) was higher (P < 0.001) when the ear canal was sealed (range of mean differences was 8.3-24.9 dB peSPL). This means that the signal to noise ratio can be improved by sealing the meatus because the electronic noise level is not increased. Most important is that the dynamic range of the clicking sounds was 62 dB that is larger than the effective dynamic range of a 16 bits sound card. Future studies are needed to establish normative peSPL values. However, cards with at least 24 bits A/D conversion will be required, especially in patients with suspected disc displacement with reduction, where the difference in loudness between opening and closing clicking often is large.  相似文献   
7.
目的:建立下颌前牙不同程度牙槽骨吸收后的釉质、牙本质、牙骨质、牙周膜、松质骨、皮质骨等组织的三维有限元模型。方法:利用薄层CT扫描技术与Ansys软件相结合,对层厚为1mm的CT断层影像进行分析处理。结果:模型具有良好的几何相似性,共有单元约13万个,节点约19万个,数据量约130MB,可以根据要求任意旋转、缩放、透视、剖开,进行多种方式观察;并可以按照不同研究目的和要求,对模型进行简单的修改和调整,模拟牙槽骨吸收、联冠修复等临床治疗所需的几何形态,考查各种约束和加载条件下前牙的力学反应;讨论了约束的处理和载荷的施加方式。结论:薄层CT扫描技术与Ansys软件相结合建立的三维有限元模型,能较精确地模拟实际情况,为进一步研究下颌前牙牙槽骨吸收和联冠修复奠定了良好的基础。  相似文献   
8.
The objective of this study was to investigate empirically the image layer characteristics of the PC 1000 Mark II. Radiographs were taken of a lead resolution grid positioned at 1 mm increments along angular intervals of the projected x-ray beam. The receptor was T-Mat G film combined with Lanex Regular Screens. The path of the effective rotation center was determined using a film positioned horizontally at right angles to the slit beam. The vertical magnification factor, horizontal magnification and Distortion Index, corrected for the position of the tomographic layer, were calculated using a reference object placed at various resolution limits of the image layer. The beam projection angle was compared to the average dental arch shape and proximal contact angle. The maximum resolution observed at the central plane of the image layer was 4 lp · mm−1. The image layer width at the 1.5 lp · mm−1 resolution contour varied from 12 mm anteriorly to 41 mm posteriorly. The vertical magnification factor within the image layer showed a linear increase along the beam path from 1.21 to 1.36. The horizontal magnification varied from 1.07 to 1.71, and the Distortion Index from 0.85 to 1.15. The beam projection angulations to the average arch shape ranged from 90° anteriorly to 115° in the premolar segments and 105° in the molar regions. The empirically derived image layer of the PC 1000 Mark II conforms to the shape of the average dental arch and that found using MTF analysis. The spatial resolution attained using a standard receptor is within the acceptable range.  相似文献   
9.
应用结构光三维扫描技术重建面部软组织形态的初步研究   总被引:2,自引:2,他引:2  
目的评价结构光三维扫描技术对面部软组织形态三维重建的可行性。方法应用基于格雷码和相位移动技术原理的结构光三维扫描技术,对1名志愿者面部及其面部石膏模型进行扫描,通过Imageware和Geomagic软件对获取的三维点云信息进行去噪、精简、平滑、三角化等数字化处理,重建面部和石膏模型的三维图像。比较三维重建图像测量项目结果和面部实际测量结果的差异。结果结构光三维扫描技术可完整重建志愿者面部的软组织形态,能较好地还原面部实际情况。结论基于格雷码和相位移动技术原理的结构光三维扫描技术能准确地重建面部软组织形态,可为面部缺损的三维重建奠定基础。  相似文献   
10.
The clinical use of imaging modalities in dentistry has so far been limited to hospitals affiliated with dental schools in Japan. The recent advances in digital radiology in dentistry, however are expected to help close the gap. Digital images are easy to transmit with its related informtion by telecommunications between the general practitioner and hospitals, among the hospitals and between the department of oral and maxillofacial radiology and the other clinical departments within the hospital. Digital radiography also is expected to help make radiographic information more accessible to general practitioners in Japan. Therefore, the demand for precise interpretation of images and the proper use of ionizing radiation in dentistry will be greater than ever, increasing the demand for specialists in oral and maxillofacial radiology. Furthermore, oral radiologists have to have enough experience and skill to meet the demand for consultaion and discussion from other departments and general practitioners across national borders and fields of specialty.  相似文献   
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