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11.
High-fidelity anatomical models can be produced with three-dimensional (3D) scanning techniques and as such be digitally preserved, archived, and subsequently rendered through various media. Here, a novel methodology—digital body preservation—is presented for combining and matching scan geometry with radiographic imaging. The technique encompasses joining layers of 3D surface scans in an anatomical correct spatial relationship. To do so, a computed tomography (CT) volume is used as template to join and merge different surface scan geometries by means of nonrigid registration into a single environment. In addition, the use and applicability of the generated 3D models in digital learning modalities is presented. Finally, as computational expense is usually the main bottleneck in extended 3D applications, the influence of mesh simplification in combination with texture mapping on the quality of 3D models was investigated. The physical fidelity of the simplified meshes was evaluated in relation to their resolution and with respect to key anatomical features. Large- and medium-scale features were well preserved despite extensive 3D mesh simplification. Subtle fine-scale features, particular in curved areas demonstrated the major limitation to extensive mesh size reduction. Depending on the local topography, workable mesh sizes ranging from 10% to 3% of the original size could be obtained, making them usable in various learning applications and environments.  相似文献   
12.
Radiative imaging of combustion flame in furnace of power plant plays an increasingly important role in combustion diagnosis. This paper presents a new method for calculating the radiative imaging of three-dimensional (3D) combustion flame based on Monte Carlo method and optical lens imaging. Numerical simulation case was used in this study. Radiative images were calculated and images obtained can not only present the energy distribution on the charge-coupled device (CCD) camera target plane but also reflect the energy distribution condition in the simulation furnace. Finally the relationships between volume ele- ments and energy shares were also discussed.  相似文献   
13.
提出一种可见光域的相干衍射成像方法.该方法在待测样品面引入一个已知的标准物体作为先验信息,并通过控制激光光束的照明范围得到2幅不同输入信息下的衍射图.依据这2幅衍射图和已知的先验信息,使用本文提出的相位恢复算法,在计算机数值模拟和光学实验中重建待测样品的复振幅信息.该方法仅需2幅衍射图即可进行无透镜成像,因此其成像过程较为简便,具有一定的实用价值.  相似文献   
14.
物体的成像规律及作图方法贯穿几何光学的始终,在折射或反射、特别是在光具组的成像过程中,往往会出现虚物的作图求像,而教材又没有具体阐明相应的内容,针对这种情况,在近轴条件下,用平行于主光轴的入射光线的性质阐明虚物在各光学元件中的成像规律,并对主光轴上虚物点的作用给出一般的方法。  相似文献   
15.
“医学影像物理学”是医药院校医学影像学专业的一门专业基础课,学生普遍反映课程内容繁多且难以融会贯通。为提高“医学影像物理学”课程的教学质量,通过分析“医学影像物理学”的课程特点及学生特点,在中医药院校“医学影像物理学”的授课中应用思维导图法,融合引导式教学方法,分别从课前导学、章末总结、对比归纳学习易混淆概念等维度进行课程教学设计。结果表明,思维导图引导式教学模式,可以帮助学生提高自主学习积极性,锻炼知识整合和逻辑思维能力,学生对课程设计整体评价较高,对其他影像学专业课程教学具有一定的参考意义。  相似文献   
16.
贵州因煤炭开采形成大面积的采空区,很多采空区积水水患灾害严重。高密度电法是贵州煤矿采空区积水勘探最常用方法,通过分析其制约因素,总结该种勘探技术方法的工程特征,对高密度电法在勘探贵州煤矿采空区积水有一定的指导意义。  相似文献   
17.
兽医影像学是临床兽医师诊疗疾病所需要的重要课程。为激发学生的学习兴趣,培养学生的读片能力,提高教学质量,将基于病例的学习模式引入影像学的教学中,观察该方法对教学的影响。实践证实,该模式有效提高了学生的学习兴趣和教学质量,值得在临床教学中进行推广。  相似文献   
18.
Marmosets are highly social non-human primates that live in families. They exhibit rich vocalization, but the neural basis underlying this complex vocal communication is largely unknown. Here we report the existence of specific neuron populations in marmoset A1 that respond selectively to distinct simple or compound calls made by conspecific marmosets. These neurons were spatially dispersed within A1 but distinct from those responsive to pure tones. Call-selective responses were markedly diminished when individual domains of the call were deleted or the domain sequence was altered, indicating the importance of the global rather than local spectral-temporal properties of the sound. Compound call-selective responses also disappeared when the sequence of the two simple-call components was reversed or their interval was extended beyond 1 s. Light anesthesia largely abolished call-selective responses. Our findings demonstrate extensive inhibitory and facilitatory interactions among call-evoked responses, and provide the basis for further study of circuit mechanisms underlying vocal communication in awake non-human primates.  相似文献   
19.
In recent years, there has been a growing interest in white matter anatomy of the human brain. With advances in brain imaging techniques, the significance of white matter integrity for brain function has been demonstrated in various neurological and psychiatric disorders. As the demand for interpretation of clinical and imaging data on white matter increases, the needs for white matter anatomy education are changing. Because cross‐sectional images and formalin‐fixed brain specimens are often insufficient in visualizing the complexity of three‐dimensional (3D) white matter anatomy, obtaining a comprehensible conception of fiber tract morphology can be difficult. Fiber dissection is a technique that allows isolation of whole fiber pathways, revealing 3D structural and functional relationships of white matter in the human brain. In this study, we describe the use of fiber dissection in combination with plastination to obtain durable and easy to use 3D white matter specimens that do not require special care or conditions. The specimens can be used as a tool in teaching white matter anatomy and structural connectivity. We included four human brains and show a series of white matter specimens of both cerebrum and cerebellum focusing on the cerebellar nuclei and associated white matter tracts, as these are especially difficult to visualize in two‐dimensional specimens and demonstrate preservation of detailed human anatomy. Finally, we describe how the integration of white matter specimens with radiological information of new brain imaging techniques such as diffusion tensor imaging tractography can be used in teaching modern neuroanatomy with emphasis on structural connectivity. Anat Sci Educ. 7: 47–55. © 2013 American Association of Anatomists.  相似文献   
20.
目的:研究近红外荧光分子探针,Cy5.5葡萄糖胺(Cy5.5-2DG),能否在活体水平上对小鼠诱导性关节炎(CIA)炎症进行显像。方法:对患有CIA的小鼠注射18F-脱氧葡萄糖(18F-FDG),1h后,进行Micro PET成像。在18F-FDG放射性衰变以后,通过尾静脉对小鼠注射Cy5.5-2DG。Cy5.5-2DG对关节炎组织的靶向性和保留性通过Xenogen IVIS 200光学成像仪进行评估和量化分析。患病小鼠体内的炎症组织通过18F-FDG-Micro PET扫描清晰可见,从该小鼠体内的Cy5.5-2DG的近红外荧光成像可以看出Cy5.5-2DG在关节组织的分布模式和18F-FDG极其相似;定量分析进一步表明关节炎组织在1 h后对18F-FDG的摄取量和Cy5.5-2DG在不同时刻的摄取量有很好的相关性(r2〉0.65)。结果:18FFDG的摄取量和Cy5.5-2DG累积量之间良好的相关性,为进一步研究Cy5.5-2DG用于评估药物消炎治疗提供了依据。结论:NIRF葡萄糖衍生物Cy5.5-2DG可以检测小鼠手掌的关节炎组织,更重要的是Cy5.5-2DG在关节炎组织中的累积程度与18F-FDG摄取量有很大的正相关。  相似文献   
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