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41.
Purpose. To assess the accuracy of different MR sequences for the detection of articular cartilage abnormalities in rheumatoid arthritis. Design and patients. Ten metacarpophalangeal joints and 10 metatarsophalangeal joints (specimens from arthritis patients undergoing ablative joint surgery) were examined with a fat-suppressed (FS) 3D FLASH, a FS 3D FISP, a FS 2D fast spin-echo T2-weighted, and a 2D FS spin-echo T1-weighted sequence. Each cartilage lesion and each cortical lesion was graded from 0 to 4 (modified Outerbridge staging system). Subsequently, the results of each sequence were compared with the macroscopic findings and statistically tested against each other. Results. The study shows that 3D gradient-echo sequences with fat suppression were best for imaging and grading of cartilage lesions in arthritis of the small joints of the hands and feet. Using 3D techniques, all grade 2, grade 3, and grade 4 lesions of cartilage or cortical bone were detected. Conclusion. FS 3D gradient-echo techniques were best for the detection and grading of hyaline cartilage and subchondral bone lesions in rheumatoid arthritis. MRI has a great potential as an objective method of evaluating cartilage damage and bone erosions in rheumatoid arthritis.  相似文献   
42.
Localised agenesis of the scalp is the most frequent patern in aplasia cutis congenita (ACC), a congenital absence of the skin and occasionally of deeper layers. Several clinical groups are characterised by the location and pattern of skin defects, associated malformations and the mode of inheritance. Death occurs in 20% of cases, secondary to the associated anomalies, to infections or to haemorrhage from ulceration of the sagittal sinus when there is also a defect of the underlying skull. In this latter case, we close the defect by two rotational scalp flaps (Orticochea technique) at birth. A three-dimensional CT study is useful for showing the extent of the skull defect and the deformity of the craniofacial complex and the changes in the bone after treatment.  相似文献   
43.
建立模拟功能状态下的下颌骨三维有限元模型   总被引:16,自引:0,他引:16  
本文在三维影像重建和三维有限元分析技术的基础上,建立了正常人和颞下颌关节疾病患者正中咬合时下颌骨的三维有限元模型。下颌骨螺旋CT和有限元模型三维重建影像的几何相似性良好,加载方式符合生理状况,比较真实地反映和模拟了功能状态下颞下颌关节与牙合的受力情况。为对颞下颌关节在各种状况下的生物力学行为进行分析和研究创造了条件。  相似文献   
44.
Three-dimensional recording of the surface of the human body or of certain anatomical areas has gained an ever increasing importance in recent years. When recording living surfaces, such as the human face, not only has a varying degree of surface complexity to be accounted for, but also a variety of other factors, such as motion artefacts. It is of importance to establish standards for the recording procedure, which will optimise results and allow for better comparison and validation. In the study presented here, the faces of five male test persons were scanned in different experimental settings using non-contact 3D digitisers, type Minolta Vivid 910). Among others, the influence of the number of scanners used, the angle of recording, the head position of the test person, the impact of the examiner and of examination time on accuracy and precision of the virtual face models generated from the scanner data with specialised software were investigated. Computed data derived from the virtual models were compared to corresponding reference measurements carried out manually between defined landmarks on the test persons' faces. We describe experimental conditions that were of benefit in optimising the quality of scanner recording and the reliability of three-dimensional surface imaging. However, almost 50% of distances between landmarks derived from the virtual models deviated more than 2mm from the reference of manual measurements on the volunteers' faces.  相似文献   
45.
 We present a rare case of a 27-year-old man sustaining a bilateral fracture dislocation of the sacroiliac joints without disruption of the anterior pelvis, following a fall from a height. Reconstructed images in the coronal plane and three-dimensional CT images were invaluable in the diagnosis and assessment of this injury.  相似文献   
46.
牟鑫 《医疗设备信息》2003,18(11):34-35
近年来,超声定量检查技术在临床的应用为心血管疾病患者的心功能评估提供了量化的依据,本文介绍了超声诊断仪的使用部分最新定量检查技术。  相似文献   
47.
为解决骨盆不稳定性骨折固定难,易产生并发症的难题,结合骨盆的特征进行研究,设计出一种新型骨盆骨折固定器,经62例骨盆不稳定性骨折的治疗观察,随访6个月~2年零6个月,治疗前后X线检查及临床疗效评定:治愈50例,好转12例,认为该固定器设计合理,操作简便,固定牢靠,有加压、撑开、纠正旋转等多项功能结合干一体,仅通过四枚4mm螺纹针,穿入髂骨的髂前上棘处,是一种治疗骨盆不稳定性骨折比较新颖和理想的外固定器。  相似文献   
48.
将一种快速、灵敏、可靠、简便的抗癌活性微量测定技术——~3H—TdR前体掺入技术用于复方中药抗癌制剂制备工艺筛选,短期内即拟定出较合理的工艺,经临床及14项生物学指标综合评定,该制剂疗效好,无明显的毒副作用。表明把一些快速、灵敏的医学检测技术引入药物制备工艺、质量标准及稳定性研究,可克服由于活性成分不清楚带来的一些困难,拓宽了研究途径,提高了研究水平。  相似文献   
49.
The retino-collicular neuron terminals containing type A monoamine oxidase (MAO-A) in the stratum griseum superficiale of the rat superior colliculus were analyzed to provide a morphologic basis for the physiologic role of these neurons in the visual pathway. A computer-assisted, three-dimensional re-construction of the terminal complex associated with the MAO-A-positive terminals was performed. MAO-A-positive terminals originated in the retina and terminated in the stratum griseum superficiale. This was confirmed by tract tracing and enucleation experiments. The terminals were densely grouped in clusters of irregularly shaped swellings. Electron microscopy revealed that the MAO-A-positive terminals were located in a glomerulus-like structure. In this terminal complex, a significant proportion of the axonal profiles (42.96%) synapsed with the MAO-A-positive terminals. Most of the profiles (24.16%) resembled presynaptic dendrites, which represent intermediate elements between the retinal terminals and conventional dendrites. Unlike the glomerulus in the dorsal lateral geniculate body, the MAO-A-positive terminal swellings were not located in the central part of the terminal complex. The terminals had an irregular shape and were located in the complex. The terminal complex was partially ensheathed by glial processes. Furthermore, the membrane surfaces exhibiting synaptic specializations were very small compared with the total surface of the terminal swellings. The membrane length of the synaptic specialization was 5.38% of the total perimeter of the MAO-A-positive terminals.  相似文献   
50.
Taking as its point of departure the medicalization thesis and its limitations, this paper provides a critical discussion of certain more recent theoretical perspectives on life in contemporary society, and their relevance for understanding the relationship between modern medicine and the lay populace. In particular, attention is paid to the contours and existential parameters of life in ‘late’ modernity in terms of the following four key themes: (i) modernity as a ‘reflexive’ social order; (ii) ‘risk’ and the dialectic of scientific and social rationality; (iii) the ‘mediation’ of contemporary experience; and (iv) lay ‘re-skilling’ and the ‘life political’ agenda. On the basis of this, it is argued that far from being simply passive and dependent, a ‘critical distance’ is beginning to emerge between modern medicine and the lay populace; a situation which resonates with broader social trends and currents within society at large.  相似文献   
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