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11.
Jefferson骨折复位钢板的设计、改良及初步临床应用   总被引:1,自引:0,他引:1       下载免费PDF全文
 目的介绍Jefferson骨折复位钢板系统(Jefferson-fracture reduction plate, JeRP)及其相关参数,评估其改良前后的临床疗效。方法对Jefferson骨折患者应用螺旋CT三维重建排除寰椎横韧带断裂后,采用原型JeRP系统进行手术治疗,分析其初步临床应用的疗效及出现的问题。根据应用中的不足,通过寰椎三维重建模型,进行应用解剖学研究并测量相关解剖数据,重新确定寰椎侧块上、下位螺钉的最佳进钉点和长度,根据该数据设计、改良JeRP钢板并予以临床应用。术后采用颈椎过伸、过屈位X线片评估是否存在寰枢椎不稳,应用CT扫描观察骨折愈合情况。结果8例Jefferson骨折患者行经口咽寰椎骨折复位、原型JeRP钢板内固定术,术后平均随访6.3个月,所有患者术后枕颈部疼痛逐渐改善,咽后壁切口愈合良好,未见感染,骨折均达到解剖复位及骨性愈合,术后随访未见寰枢椎失稳,但其中3例患者因寰椎侧块上位螺钉穿破寰枕关节而导致颈椎活动受限。针对此问题,并通过应用解剖学测量,模拟置钉显示寰椎侧块外1/3平分线与寰椎上、下关节面交点所形成线段的中点作为寰椎侧块上位螺钉的进钉点,可保证JeRP钢板侧块上位螺钉不穿透上关节面,同时可保证足够空间置入下位螺钉,具备临床可行性。根据此结果设计出改良JeRP钢板,应用于4例Jefferson骨折患者,术后影像学检查证实所有螺钉均位于寰椎的侧块中。结论原型JeRP初步应用显示较好的疗效,但仍存在寰椎侧块上位螺钉穿透寰枕关节的可能;改良后钢板的设计更加符合寰椎的解剖结构,基本可以保证螺钉位于侧块中。  相似文献   
12.
The nucleus of the solitary tract (NST) processes gustatory and related somatosensory information rostrally and general viscerosensory information caudally. To compare its connections with those of other rodents, this study in the C57BL/6J mouse provides a subnuclear cytoarchitectonic parcellation (Nissl stain) of the NST into rostral, intermediate, and caudal divisions. Subnuclei are further characterized by NADPH staining and P2X2 immunoreactivity (IR). Cholera toxin subunit B (CTb) labeling revealed those NST subnuclei receiving chorda tympani nerve (CT) afferents, those connecting with the parabrachial nucleus (PBN) and reticular formation (RF), and those interconnecting NST subnuclei. CT terminals are densest in the rostral central (RC) and medial (M) subnuclei; less dense in the rostral lateral (RL) subnucleus; and sparse in the ventral (V), ventral lateral (VL), and central lateral (CL) subnuclei. CTb injection into the PBN retrogradely labels cells in the aforementioned subnuclei; RC and M providing the largest source of PBN projection neurons. Pontine efferent axons terminate mainly in V and rostral medial (RM) subnuclei. CTb injection into the medullary RF labels cells and axonal endings predominantly in V at rostral and intermediate NST levels. Small CTb injections within the NST label extensive projections from the rostral division to caudal subnuclei. Projections from the caudal division primarily interconnect subnuclei confined to the caudal division of the NST; they also connect with the area postrema. P2X2‐IR identifies probable vagal nerve terminals in the central (Ce) subnucleus in the intermediate/caudal NST. Ce also shows intense NADPH staining and does not project to the PBN. J. Comp. Neurol. 522:1565–1596, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
13.
The relationship between structure and function is an invaluable context with which to explore biological mechanisms of normal and dysfunctional hearing. The systematic and topographic representation of frequency originates at the cochlea, and is retained throughout much of the central auditory system. The cochlear nucleus (CN), which initiates all ascending auditory pathways, represents an essential link for understanding frequency organization. A model of the CN that maps frequency representation in 3D would facilitate investigations of possible frequency specializations and pathologic changes that disturb frequency organization. Toward this goal, we reconstructed in 3D the trajectories of labeled auditory nerve (AN) fibers following multiunit recordings and dye injections in the anteroventral CN of the CBA/J mouse. We observed that each injection produced a continuous sheet of labeled AN fibers. Individual cases were normalized to a template using 3D alignment procedures that revealed a systematic and tonotopic arrangement of AN fibers in each subdivision with a clear indication of isofrequency laminae. The combined dataset was used to mathematically derive a 3D quantitative map of frequency organization throughout the entire volume of the CN. This model, available online ( http://3D.ryugolab.com/ ), can serve as a tool for quantitatively testing hypotheses concerning frequency and location in the CN. J. Comp. Neurol. 521:1510–1532, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
14.
目的探讨椎弓根内壁显露在寰枢椎椎弓根固定的临床应用价值。方法通过显露寰椎椎弓根内壁和枢椎椎弓根内上壁,共置入椎弓根螺钉219枚,其中寰椎107枚,枢椎112枚。结果一次性置钉成功198枚,术后X线和CT检查螺钉均位于椎弓根内,上倾及内倾角度良好,无置钉有关的并发症。结论术中显露寰椎椎弓根内壁和枢椎椎弓根内上壁,可以提高寰枢椎椎弓根螺钉的置钉准确率,减少透视次数,减少出血量,节约手术时间,适合临床推广使用。  相似文献   
15.
Completion of the Human Genome Project and recent developments in proteomics make it possible to systematically generate affinity reagents to a large portion of the proteome. Recently an antibody-based human protein atlas covering many organs including four areas of the brain has been released (www.proteinatlas.org). Due to the heterogeneity, size, and availability of tissue a more thorough analysis of the human brain is associated with considerable difficulties. Here we applied 120 antibodies raised against 112 human gene products to the smaller rat brain, a rodent animal model, where a single section represents a 'superarray' including many brain areas, and consequently allowing analysis of a huge number of cell types and their neurochemicals. Immunoreactive structures were seen in the investigated brain tissue after incubation with 56 antibodies (46.6%), of which 25 (20.8%) showed a clearly discrete staining pattern that was limited to certain areas, or subsets of brain cells. Bioinformatics, pre-adsorption tests and Western blot analysis were applied to identify non-specific antibodies. Eleven antibodies, including such raised against four 'ambiguous' proteins, passed all validation criteria, and the expression pattern and subcellular distribution of these proteins were studied in detail. To further explore the potential of the systematically generated antibodies, all 11 antibodies that passed validation were used to analyze the spinal cord and lumbar dorsal root ganglia after unilateral transection of the sciatic nerve. Discrete staining patterns were observed for four of the proteins, and injury-induced regulation was found for one of them. In conclusion, the study presented here suggests that a significant portion (10%) of the antibodies generated to a human protein can be used to analyze orthologues present in the rodent brain and to produce a protein-based atlas of the rodent brain. It is hoped that this type of antibody-based, high throughput screening of brain tissue from various rodent disease models will provide new information on the brain chemical neuroanatomy and insights in processes underlying neurological pathologies.  相似文献   
16.
目的观察正常人的上颈椎椎管后缘弧线形态、寰椎后结节位置,确定寰枕枢角(∠AOA)、寰枢椎比值(RAA)的正常值及其临床意义。方法200例正常成人和9例寰椎发育过小者上颈椎侧位片,用数码相机输入计算机,采用Coreldrew10图像分析软件进行统计学分析,确定正常成人的正常值,并将9例先天性寰椎过小畸形者的变化值与之比较。结果正常成人的上颈椎椎管后缘弧线平滑、自然,寰椎后结节位置为正值,各测量指标呈正态分布,∠AOA为(151.48±5.75)°,RAA为(1.94±0.11),SAC为(24.13±2.47)mm;寰椎发育过小者的寰椎前结节位于正常位置,后结节前移,上颈椎椎管后缘弧线弧度不自然,在寰椎后结节处发生转折,9例中8例寰椎后结节位置为负值;∠AOA(133.14±5.78)°,与正常组比较差异有非常显著性(P<0.01);RAA(1.72±0.06)、SAC(19.14±1.46)mm,与正常组比较差异均有显著性(P<0.05)。结论正常成人的上颈椎椎管后缘弧线弧度自然,寰椎后结节位置为正值,∠AOA≥142.02°,RAA≥1.76;寰椎发育过小者的寰椎前结节位置正常,而后结节前移,上颈椎椎管后缘弧线在该处发生转折,寰椎后结节位置为负值,∠AOA和RAA明显变小。上述指标对确定寰椎发育过小有一定意义。  相似文献   
17.
18.
脑模板是能代表一个群体的大脑模型,包含大脑结构及分区标签等信息,在脑神经影像学分析领域具有重要作用。脑模板可为群体分析提供标准归一化空间,将先验知识如分割图谱和解剖标识映射到新图像上进行分析。构建脑模板包括图像预处理、图像配准和模板构建三步。随着脑影像学处理和分析技术的提高,脑模板的质量逐渐提升、应用范围逐渐扩大。本文对人脑模板的构建方法和应用进展进行综述。  相似文献   
19.
Constructing an atlas from a population of brain images is of vital importance to medical image analysis. Especially in neuroscience study, creating a brain atlas is useful for intra‐ and inter‐population comparison. Research on brain atlas construction has attracted great attention in recent years, but the research on pediatric population is still limited, mainly due to the limited availability and the relatively low quality of pediatric magnetic resonance brain images. This article is targeted at creating a high quality representative brain atlas for Chinese pediatric population. To achieve this goal, we have designed a set of preprocessing procedures to improve the image quality and developed an intensity and sulci landmark combined groupwise registration method to align the population of images for atlas construction. As demonstrated in experiments, the newly constructed atlas can better represent the size and shape of brains of Chinese pediatric population, and show better performance in Chinese pediatric brain image analysis compared with other standard atlases. Hum Brain Mapp 35:3880–3892, 2014. © 2014 Wiley Periodicals, Inc .  相似文献   
20.
目前三叉神经的纤维跟踪成像过程中普遍存在人工依赖性问题,主要包括人工绘制感兴趣区域(ROI)及手动筛选目标纤维束,导致结果的不确定性和数据误差。针对此类问题,提出一种数据驱动的三叉神经纤维自动分割算法。利用多组大脑样本的纤维数据,建立数据驱动的纤维聚类图谱,实现新样本纤维数据的自动分割,直接得到三叉神经纤维束。在实验中,选择25组青年健康人的数据作为样本数据。首先,利用FSL软件分割工具提取脑干作为ROI,进行确定性纤维跟踪。其次,通过对20组纤维数据进行多样本配准和谱聚类,创建数据驱动的纤维聚类图谱。根据三叉神经细小的特点,在建立纤维图谱过程中,通过对脑干纤维束进行二次分类来标注三叉神经纤维束。最后,选择5组青年健康人的新样本数据,将其脑干纤维数据应用纤维图谱自动分割得到三叉神经纤维束,并计算同一样本数据的自动分割结果与手动分割结果之间的加权Dice系数。结果显示,所提出的方法成功分割5组数据的三叉神经纤维束,而传统人工方法成功识别4组三叉神经纤维束,两者结果之间的加权Dice系数分别为0.865,0.939,0.824,0.942。该方法可以有效避免人为因素的影响,提高神经外科医生与颅神经研究者的工作效率。  相似文献   
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