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1.
Our knowledge of the radiological spectrum of myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) is growing rapidly. An update on the radiological features of the disease, and its evolution is thus necessary. Magnetic resonance imaging (MRI) has an increasingly important role in the differential diagnosis of MOGAD particularly from aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD), and multiple sclerosis (MS). Differentiating these conditions is of prime importance because the management is different between the three inflammatory diseases, and thus could prevent further attack-related disability. Therefore, identifying the MRI features suggestive of MOGAD has diagnostic and prognostic implications. We herein review optic nerve, spinal cord and the brain MRI findings from MOGAD adult patients, and compare them to AQP4-NMOSD and MS.  相似文献   
2.
Soft tissue sarcomas (STS) are rare tumours presenting as soft tissue lumps. Ultrasound is often the primary modality for the initial assessment, with MRI the mainstay for lesion characterisation. PET/CT along with other emerging MRI sequences are used in certain situations as an adjunct and problem solving tool in STS staging and assessment of disease recurrence. Recent advances include the promise of whole body MRI, hybrid PET/MRI, diffusion weighted imaging, dynamic contrast enhanced MRI and advances in artificial intelligence. This article discusses current concepts in extremity STS imaging and highlights recent advances.  相似文献   
3.
《Neuro-Chirurgie》2022,68(2):239-242
IntroductionIndocyanine green (ICG) is commonly used to visualize cerebral vasculature, particularly in the management of cerebral aneurysms. There have also been attempts to use ICG for visualization of tumors. Injection of ICG followed by immediate fluorescence microscopy is limited by the short time window for imaging and administration and restricted depth of imaging. Second Window Indocyanine Green (SWIG) addresses these issues by allowing for longer contrast times and the imaging of deeper regions of brain tissue. Biopsy of spinal cord lesions is often difficult for a variety of reasons, including the delicate nature of the tissue and differentiating normal from lesional tissue visually, especially in lesions with heterogeneous enhancement.MethodsIn this case report, we describe the use of second window ICG to facilitate the visualization of a spinal cord lesion and subsequent biopsy of the lesion.ResultsThis patient is a 24-year-old female who had recurrence of a suprasellar germinoma. An MRI of the rest of the neuraxis was performed to assess for the presence of drop metastases. The spinal cord from C2-5 was expanded with areas of patchy enhancement; however, this lesion was asymptomatic. The patient's oncologist requested a biopsy of this lesion to help direct subsequent care of her recurrent germinoma. The day before surgery, the patient had an intravenous injection of ICG dye. She then underwent a C3-5 laminectomy for biopsy of her cervical intramedullary lesion. After opening of the dura, no visible abnormality of the spinal cord could be identified. A Stryker endoscope showed an area of ICG uptake in the cord at approximately the C3-4 level. A midline myelotomy was centered over the ICG demarcated area and several samples were taken for pathology. Final biopsy results determined the lesion to be spinal cord parenchyma with perivascular and intraparenchymal lymphocytes – not consistent with spinal cord tumor or germinoma.ConclusionSecond Window ICG is effective in visualizing otherwise visually unremarkable spinal cord lesions. This technology can facilitate biopsy of these lesions and possibly their surgical resection.  相似文献   
4.
5.
Nanotechnology offers several advantages for drug delivery. However, there is the need for addressing potential safety concerns regarding the adverse health effects of these unique materials. Some such effects may occur due to undesirable interactions between nanoparticles and the immune system, and they may include hypersensitivity reactions, immunosuppression, and immunostimulation. While strategies, models, and approaches for studying the immunological safety of various engineered nanoparticles, including metal oxides, have been covered in the current literature, little attention has been given to the interactions between iron oxide-based nanomaterials and various components of the immune system. Here we provide a comprehensive review of studies investigating the effects of iron oxides and iron-based nanoparticles on various types of immune cells, highlight current gaps in the understanding of the structure–activity relationships of these materials, and propose a framework for capturing their immunotoxicity to streamline comparative studies between various types of iron-based formulations.  相似文献   
6.
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al.  相似文献   
7.
OBJECTIVE: This study evaluated the feasibility of a high frequency ultrasound scan to examine the 3D morphology of Streptococcus mutans biofilms grown in vitro. METHODS: Six 2-day S. mutans biofilms and six 7-day biofilms were grown on tissue culture membranes and on bovine dentine discs. A sterile growth medium on the membrane and disc were used as controls. Surfaces were rinsed and then immersed in sterile saline. High-frequency ultrasound imaging system was used to scan these surfaces at 55MHz, and a computer program calculated the average thickness of the biofilm layer from the 3D images. RESULTS: 3D pictures of the biofilm layers were obtained. Different cross-sections and plains are easily demonstrated. The average thickness of the 7-day biofilm was significantly bigger than the 2-day on both the membranes and dentinal discs. No structures were observed on the sterile membrane or disc. CONCLUSION: Three-dimensional structural imaging in situ is possible without damaging the biofilm layer in a quick and easy manner and can therefore be used to evaluate biofilms longitudinally as a function of time.  相似文献   
8.
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   
9.
目的 使用新研制的非接触式三维图像检测系统对健康人牙齿咬合面的磨损情况进行定量测定。方法 选择 32名牙列完整的健康中老年人 5年前后的牙颌模型 ,用统一方法确定个体参照平面和上颌第一恒磨牙测量范围 ,用非接触式三维图像检测系统测量研究对象 5年内上颌第一恒磨牙咬合面的磨损量和平均磨损速度。结果  5年内上颌第一恒磨牙咬合面的磨损情况 :以高度平均值变化为指标 ,平均磨损量为 0 2 93mm ,平均每年磨损速度为 0 0 5 9mm ;以体积变化为指标 ,平均磨损量为 97 881mm3 ,平均磨损速度为 19 5 76mm3 /年。结论 非接触式三维图像检测系统及相关的必要设置 ,可作为测量健康人牙齿磨损情况的有效工具。其个别设置条件尚待进一步改进  相似文献   
10.

Background

Both MRI and breast-specific gamma imaging are tools for surgical planning in newly diagnosed breast cancer. Breast-specific gamma imaging (BSGI) is used less frequently although it is of similar utility and lower cost. We compared the diagnostic and cost efficacy of BSGI with MRI.

Methods

Retrospective review of 1,480 BSGIs was performed in a community breast health center, 539 had a new diagnosis of cancer, 75 patients having both MRI and BSGI performed within 2 months of each other. Institutional charges for BSGI ($850) and MRI ($3,381) were noted.

Results

BSGI had a sensitivity of 92%, specificity of 73%, positive predictive value of 78%, and negative predictive value of 90%. This compared favorably with MRI that had sensitivity of 89%, specificity 54%, positive predictive value 67%, and negative predictive value 83%. The accuracy of BSGI was higher at 82% vs MRI at 72%. Total cost of MRI imaging was $253,575 vs BSGI at $63,750.

Conclusions

BSGI is a cost-effective and accurate imaging study for further evaluation of dense breast tissue and new diagnosis of cancer.  相似文献   
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