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81.
目的:应用CT技术对成年实验猕猴全身进行断层扫描,探讨CT技术对猕猴疾病的临床诊断意义,建立正常成年猴CT影像图谱,为CT技术在猕猴解剖学的研究、疾病的诊断及科学实验方面的应用,提供影像学的基础资料。方法:(1)选择实验猕猴10只,雌雄各半,年龄6~10岁,进行全身CT断层扫描。(2)试验猴全身麻醉后,置于CT诊断床上,取头前尾后仰卧位,采用平扫及增强扫描技术,进行容积数据采集,获取正常猕猴全身CT影像图片。(3)利用CT图像后处理技术对扫描获得的容积数据进行2D或3D图像重组处理。结果:(1)获得实验猕猴活体结构CT连续断层图像数据集。(2)从扫描和重建图像中精选具有解剖意义的图像,编辑建立实验猕猴CT影像图谱。文中展示4幅代表性扫描图片和5幅三维重建图像。(3)从比较解剖学的角度,阐述猕猴结构特点及与人类的区别。结论:(1)CT影像能够较好显示及分辨猕猴的组织器官结构,骨骼、大血管界面清晰;但软组织、神经、肌肉组织等显示不够清晰。(2)试验获得了正常成年猕猴全身的影像学基础资料,为CT技术在猕猴影像学研究、解剖学研究、疾病的临床诊断及科学实验方面的应用,提供了参考。(3)在猕猴CT影像学方面做了初步摸索,对猕猴进行CT扫描的技术参数选择及猕猴各器官组织定量统计数据的建立等有待进一步总结和完善。  相似文献   
82.
This article describes the importance of detecting grain deviation caused by knots and reviews the main methods used in measuring grain orientation surrounding knots. It discusses the potential of using Diffusion Tensor Magnetic Resonance Imaging to track and map the grain deviation caused by knots.  相似文献   
83.
情态表达在英语中十分丰富,人们常常研究其主观性和客观性。文章从情态表达的理解和作用出发,通过分析其主观性和客观性之分的模糊之处,提出英语话语中情态表达选用的理据:感念推理、事实推理、理论推理和语用推理。  相似文献   
84.
A method combining fluorescence fingerprint (FF) measurement with an imaging technique was developed to visualize the distributions of gluten and starch in dough. The fluorescence images of dough at the under-, optimum- and over-mixing stages were acquired in multiple excitation and emission wavelengths constructing the FF. This data containing the FF data of each pixel in the sample image was colored according to the similarity of the FF of each pixel and the FF of gluten or starch. Furthermore, the areas corresponding to air bubbles in the dough were masked in black. The resulting image, referred to as the FF pseudocolor image, showed the distributions of gluten and starch in the dough with the incorporated bubbles. Quantitative parameters concerning gluten and starch distributions and bubble area were extracted from the dough images at each mixing stage, showing the homogenization of gluten and starch and the incorporation of bubbles with mixing. This imaging method is suggested to have an advantage over conventional imaging methods since there is no need to preprocess the sample, and any constituent in the sample can be visualized as long as there is information about the FF of the pure target constituent.  相似文献   
85.
陈华  林淑玲  沈浩 《安徽农业科学》2010,38(30):16751-16754
[目的]薇甘菊(Mikania micrantha)不同叶位对田野菟丝子(Cuscuta campestris Yuncker)的寄生行为会产生不同的寄生效应。[方法]连续3d从野外取样,采用叶绿素成像技术和分光光度计,测定寄生影响。[结果]寄生显著降低了薇甘菊第4、5片叶PSⅡ的最大光化学效率(Fv/Fm),对低光诱导下的qP和NPQ均无显著影响,却显著降低了第8、9片叶子的光合电子传递相对速率(ETR)。寄生也改变了寄主叶片的均质性。寄生非显著地降低了寄主薇甘菊第4~9片叶的叶绿素总量和类胡萝卜素含量,显著地降低了第6、7、9片叶的叶绿素a/b值。田野菟丝子茎内的色素含量均非常低,叶绿素a/b却保持与寄主薇甘菊相似的水平。[结论]田野菟丝子的寄生对寄主产生的胁迫直接影响寄主的光化学中心的活性,从而影响其光合进程。  相似文献   
86.
A review of advanced techniques for detecting plant diseases   总被引:4,自引:0,他引:4  
Diseases in plants cause major production and economic losses in agricultural industry worldwide. Monitoring of health and detection of diseases in plants and trees is critical for sustainable agriculture. To the best of our knowledge, there is no sensor commercially available for real-time assessment of health conditions in trees. Currently, scouting is most widely used mechanism for monitoring stress in trees, which is an expensive, labor-intensive, and time-consuming process. Molecular techniques such as polymerase chain reaction are used for the identification of plant diseases that require detailed sampling and processing procedure. Early information on crop health and disease detection can facilitate the control of diseases through proper management strategies such as vector control through pesticide applications, fungicide applications, and disease-specific chemical applications; and can improve productivity.The present review recognizes the need for developing a rapid, cost-effective, and reliable health-monitoring sensor that would facilitate advancements in agriculture. It describes the currently used technologies that can be used for developing a ground-based sensor system to assist in monitoring health and diseases in plants under field conditions. These technologies include spectroscopic and imaging-based, and volatile profiling-based plant disease detection methods. The paper compares the benefits and limitations of these potential methods.  相似文献   
87.
不同形态饲料对养殖水体中氮磷含量及饲料溶失率的影响   总被引:2,自引:0,他引:2  
用配方相同的膨化、硬颗粒和粉状配合饲料分别饲喂斑点叉尾鲴,通过测定养殖水体中总氮(TN)、总磷(TP)、有机物耗氧量(C()D)、氨氮(NH3-N)和饲料中总氮与总磷溶失率的变化来说明不同形态饲料对养殖水体中氮磷含量的影响.结果表明:在同一时间内,粉料养殖水体中的COD、TP、TN、NH3-N含量均要高于颗粒料和膨化料养殖水体中的C()D、TP、TN、NH3-N含量,由高到低依次为:粉料>颗粒料>膨化料.饲料中总氮和总磷的溶失率因不同的饲料加工工艺而有较大的差异.粉料组与颗粒料组的总氮和总磷溶失率差异不显著;而此2组与膨化料组的总氮和总磷溶失率差异都极显著,并且粉料的最高,颗粒料的其次,而膨化料的最低.  相似文献   
88.
The technical feasibility of performing magnetic resonance imaging (MRI) in domestic pigeons was investigated. Imaging was performed with a 1.5 Tesla magnet using a human knee surface coil. The head and coelomic cavity of isoflurane-anesthetized birds were imaged in the dorsal, sagittal, and transverse planes to produce T1-weighted, T2-weighted, and contrast-enhanced T1-weighted images. The birds were then euthanatized, formalin perfused, frozen, and sectioned in the corresponding anatomic planes. The anatomy defined by MRI was correlated with gross anatomic sections made from the same birds. The following CNS structures were identified: cerebral hemispheres, cerebellum, optic chiasm, optic lobes, brain stem, and cranial spinal cord. The cornea, lens, and vitreous were also well differentiated in dorsal section MRI's. The abdominal organs identified included proventriculus, ventriculus, intestines, cloaca, liver, kidneys, spleen, testes, and ovary. The hepatic and renal vasculature were well defined.  相似文献   
89.
HOSPITAL, RADIOLOGY, AND PICTURE ARCHIVING AND COMMUNICATION SYSTEMS   总被引:1,自引:1,他引:0  
Images generated during the course of patient evaluation and management are an integral part of the medical record and must be retained according to local regulations. Digital Imaging and Communications in Medicine (DICOM) makes it possible for images from many different imaging modalities to be distributed via a standard internet network to distant viewing workstations and a central archive in an almost seamless fashion. The DICOM standard is a truly universal standard for the dissemination of medical images. Picture Archive and Communication System (PACS) refers to the infrastructure that links modalities, workstations, the image archive, and the medical record information system into an integrated system, allowing for efficient electronic distribution and storage of medical images and access to medical record data. This paper discusses the important elements to a successful PACS implementation in a practice, including how it interacts with other practice computing systems.  相似文献   
90.
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