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991.
目的:探讨磁共振成像(MRI)对确定阻塞性睡眠呼吸暂停低通气综合征(OSAHS)病人阻塞部位的作用。方法:通过对35例OSAHS男性患者行多导睡眠仪、MRI及纤维喉镜检查配合Muller’s运动检查(FEMM)、同时对30例男性健康人的上呼吸道进行MRI检查,将两者检查结果进行比较,判定OSAHS患者上呼吸道狭窄的部位及狭窄程度,客观评价MRI对检查OSAHS患者的应用价值。结果:OSAHS患者的上呼吸道截面积明显小于健康人,轻度OSAHS患者多存在腭咽平面狭窄;中重度组OSAHA患者大部分所有平面都存在狭窄,但中度组以腭咽狭窄较明显,而重度组所有平面均存在较明显的狭窄,这种狭窄主要是由于口咽部周围软组织增生及软腭过长、肥厚及舌根宽大、肥厚所致。结论:MRI检查可判定OSAHS患者上呼吸道狭窄的部位及狭窄程度,有助于治疗方案的选择,对预估手术疗效具有重要的意义。 相似文献
992.
A. N. Chalazonitis MD Ph.D D. Koumarianos RT J. Tzovara MD P. Chronopoulos MD 《Journal of digital imaging》2003,16(2):216-229
Over the past decade, the technology that permits images to be digitized and the reduction in the cost of digital equipment allows quick digital transfer of any conventional radiological film. Images then can be transferred to a personal computer, and several software programs are available that can manipulate their digital appearance. In this article, the fundamentals of digital imaging are discussed, as well as the wide variety of optional adjustments that the Adobe Photoshop 6.0 (Adobe Systems, San Jose, CA) program can offer to present radiological images with satisfactory digital imaging quality. 相似文献
993.
目的 探讨磁共振成像及氧化铁粒子标记在干细胞治疗脑卒中模型中的应用价值.方法 线栓法建立9只大鼠大脑中动脉缺血模型,进行神经行为学评分、磁共振影像学和病理学评价,并对上述3项指标进行相关性分析.用超顺磁性氧化铁体外标记骨髓间充质干细胞,并另筛选18只脑缺血大鼠,分别接受缺血对侧皮层(n.6)、缺血同侧纹状体(n=6)的标记干细胞移植,并设对照组(n=6).分别在脑缺血后1 d、细胞移植后第1天、第7天及第14天进行磁共振扫描,观察各时间点的标记干细胞显示情况,并对各组之间梗死体积的变化进行统计学分析.结果 神经行为学评分、磁共振影像学和病理学评价对大鼠脑缺血模型评价的相关性好.磁共振各序列均可显示局部移植的标记干细胞,梯度回波序列最敏感,T2像空间分辨力高.磁共振成像可显示局部移植标记干细胞随时间推移而产生的分布变化.干细胞治疗各组之间脑梗死体积变化无明显差异.结论 磁共振成像是大鼠脑缺血模型评价的理想工具,配合氧化铁粒子标记干细胞可活体状态下了解干细胞移植后的分布变化. 相似文献
994.
Fibre optic confocal imaging (FOCI) of keratinocytes, blood vessels and nerves in hairless mouse skin in vivo 总被引:1,自引:0,他引:1
L. J. BUSSAU L. T. VO P. M. DELANEY G. D. PAPWORTH D. H. BARKLA R. G. KING 《Journal of anatomy》1998,192(2):187-194
Fibre optic confocal imaging (FOCI) enabled subsurface fluorescence microscopy of the skin of hairless mice in vivo. Application of acridine orange enabled imaging of the layers of the epidermis. The corneocytes of the stratum corneum, the keratinocytes in the basal layers and redundant hair follicles were visualised at depths greater than 100 μm. Cellular and nuclear membranes of keratinocytes of the skin were visualised by the use of acridine orange and DIOC5(3). Imaging of the skin after injection of FITC-dextran revealed an extensive network of blood vessels with a size range up to 20 μm. Blood cells could be seen moving through dermal vessels and the blood circulation through the dermal vascular bed was video-taped. The fluorescent dye 4-di-2-ASP showed the presence of nerves fibres around the hair follicles and subsurface blood vessels. Comparison was made between images obtained in vivo using FOCI and in vitro scanning electron microscopy and conventional histology. FOCI offers the potential to study dynamic events in vivo, such as blood flow, skin growth, nerve regeneration and many pathological processes, in ways which have not previously been possible. 相似文献
995.
Traditionally, radiology has been conceived as a support department providing patient scanning services to the other clinical
departments in a hospital. However, recent advancements in networking technology and related information systems such as picture
archiving and communication system (PACS) and radiology information system (RIS) provide new opportunities for inventing different
types of diagnostic imaging businesses such as teleradiology. In this article, we examined the business processes of currently
operating imaging centers and proposed a prototype of an information system that can facilitate their workflows in a more
efficient way. The principal component of our proposed system is a report management module built on extensible markup language
(XML) technologies that allows much flexibility and convenience for both imaging technicians and radiologists. 相似文献
996.
物理学对医学的贡献是巨大的,物理学与医学等学科的交叉碰撞在医学领域中产生了许多丰硕成果,现代的医学影像就是其中的成果之一。本文阐述了物理学在现代四大医学影像中的应用。 相似文献
997.
Akisue T Matsumoto K Yamamoto T Kizaki T Fujita I Yoshiya S Kurosaka M 《Pathology international》2002,52(11):730-733
This report presents a case of neural fibrolipoma arising from the superficial peroneal nerve in the ankle. A 28-year-old woman was referred with a soft tissue mass in the anterior aspect of the right ankle, which had been gradually enlarging for the past 10 years. Magnetic resonance imaging showed a mass lesion, measuring approximately 8 x 3 x 2 cm, with high to partially low signal intensity on both T1- and T2-weighted images. A band of low signal intensity within the lesion, which is indicative of coexistence with the tumor and the superficial peroneal nerve, could be detected on both T1- and T2-weighted images. The patient underwent an excisional biopsy. The specimen microscopically consisted of nerve bundles and fibro-fatty proliferation with abundant collagen fibers. Immunoreactivity for CD34 antigen antibody was detected in fibrous spindle cells. This is the first report to present an immunohistochemical profile of neural fibrolipoma. Neural fibrolipoma should be considered as a differential diagnosis when a lipomatous lesion is encountered in the foot or ankle as well as in the upper extremities. 相似文献
998.
GD Cramer DJ Allen LJA DiDio W Potvin R Brinker 《Surgical and radiologic anatomy : SRA》1990,12(4):287-290
Summary Accurate volume determination of the encephalic ventricles is of importance in several clinical conditions, including Alzheimer's presenile dementia, schizophrenia, and benign intracranial hypertension. Previous studies have investigated the accuracy with which magnetic resonance imaging (MRI) can be used in clinical practice to evaluate the encephalic ventricles. However, adequate evaluation of pathological conditions depends on a sufficient amount of morphometric data from normal subjects. To begin establishing this data base for normal subjects, we evaluated the MRI scans of 38 subjects found to have no apparent pathology and calculated the ventricular volume in each case by using methods previously developed in our laboratory. The results were then compared with published volumes determined from studies that used either ventricular casts or computerized tomographic scans. The average total ventricular volume for all 38 subjects was 17.4 cm3, while that for males was 16.3 cm3 and that for females was 18.0 cm3. A small but significant correlation was found between age of subject and ventricular volume, with ventricular size increasing with age.
Evaluation du volume des ventricules cérébraux à partir des images obtenues en résonance magnétique nucléaire chez 38 sujets humains
Résumé La détermination exacte du volume des ventricules cérébraux est importante en clinique comme par exemple dans la démence présénile d'Alzheimer, la schizophrénie et l'hypertension intracrânienne bénigne. Des études antérieures ont étudié la fiabilité de la résonance magnétique nucléaire en pratique clinique pour évaluer le volume des ventricules cérébraux. Toutefois une évaluation correcte dans les conditions pathologiques implique une bonne connaissance des données morphométriques du sujet normal. Pour établir ces données sur « le sujet normal », nous avons étudié les coupes obtenues en IRM chez 38 sujets apparemment indemnes de toute pathologie; nous avons calculé le volume ventriculaire dans chaque cas en utilisant des méthodes mises au point auparavant dans notre laboratoire. Les résultats ont été ensuite comparés avec ceux obtenus par d'autres études utilisant soit des moules ventriculaires, soit des coupes tomographiques computérisées. Le volume ventriculaire total moyen chez 38 sujets est de 17,4 cm3, mais il est chez les sujets masculins de 16,3 cm3 et chez les sujets de sexe féminin de 18 cm3. Une corrélation faible mais significative a été trouvée entre l'âge du sujet et le volume ventriculaire, étant entendu que la taille du ventricule augmente avec l'âge.相似文献
999.
Heng-Shuen Chen Fei-Ran Guo Chien-Tsai Liu Yue-Joe Lee Jye-Horng Chen Chia-Chin Lin Sheng-Mou Hou Bor-Shen Hsieh 《International journal of medical informatics》1998,50(1-3):59-68
National Taiwan University College of Medicine (NTUCM) introduced small groups of teaching and basic-clinical integrated courses for medical students in 1992. By using computer network and multimedia techniques, this study tried to overcome barriers to learning in small group teaching. The Department of Medical Informatics of NTUCM established campus networking and computer classrooms and provided Internet and intranet network services including mail, netnews, bulletin board systems (BBS), world wide web (WWW), gopher, ftp and local file servers. To implement an interactive learning environment, the authors first tried mail lists, newsgroups and BBS. Next an integrated learning system prototype on the WWW was developed to provide functions including online syllabus, discussion boards simulated to BBS, online talk, interactive case studies, virtual classroom with video on demand (VOD) and Internet medical resources. The results showed that after the medical students completed the required course of medical informatics and had good network access using a network to communicate with each other became a daily practice. In the future, the system will extend to the tutoring of clinical practice and continuing medical education. The authors expect a national medical education network and more international cooperation and exchange. 相似文献
1000.
A PC-AT based program for conversion of magnetic resonance imaging (MRI) scans into coordinate input for finite element mesh generation is presented. The program is written in Borland C + +3.1 and is compatible with every general-use personal computer, permitting the use of MS-DOS 3.0 or higher with a Microsoft mouse. The program is menu driven and does not demand specialised knowledge from the user. The system and memory requirements are minimal -- 640 kB RAM -- and it runs as a stand-alone program. A second program allows the construction of a three-dimensional representation of the limb sub-structure and generation of the FE mesh from the converted cross-sectional scans. The capabilities of the program are demonstrated using cross-sectional scans of the upper arm; the fat, muscle and bone contours were obtained to a very high level of precision (0.4 mm). 相似文献