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61.
本文设计了一种心脏冠脉狭窄程度的客观评估方法,并自行开发了工具软件对图像数据进行自动处理和计算。此后,本文采用该方法对四组心脏动态体模冠脉狭窄成像的数据进行了分析,对该客观评估方法各方面的特性进行了检验和评定。  相似文献   
62.
详细分析了参数记录数据在Tracerlab FX-FDG上的合成过程,以及造成合成故障的确切原因,从而得出正确的结论,即:对液体的添加过程是否正常,数据记录可提供准确信息,是解决问题可依赖的分析手段。  相似文献   
63.
颅面部的 CT扫描检查主要包括颅脑面部上、下颌骨、中耳、内耳、鼻窦、眼眍、眼球及颞骨茎突等部位的扫描检查 ,上述部位的扫描检查的位置的摆法 ,层面的厚度、间距 ,扫描时间及螺距等参数的选择及扫描后图像的后处理工作对检查结果的诊断至关重要。上述参数任意一个选择不当及  相似文献   
64.
 Infantile myofibromatosis is a mesenchymal tumor most commonly seen in infancy. The tumors have a variable appearance on CT/MR and often simulate a more aggressive neoplasm. This report describes CT/MR findings in cases of infantile myofibromatosis with pathologic correlation. Discussion into the success of imaging in suggesting the correct diagnosis is also addressed. Infantile myofibromatosis is a mesenchymal disorder of infancy characterized by the presence of tumorous nodules in the skin, subcutaneous tissue, muscle, viscera, and bone. Cases of solitary and multiple lesions have been described. We present the clinical, histologic, and radiographic findings of one case of the solitary form of infantile myofibromatosis that was recently diagnosed at our hospital.  相似文献   
65.
A 9-year-old boy presented with a subacute history of optic neuritis followed by brainstem involvement, with fever and a lymphocytic pleocytosis in the cerebrospinal fluid. Gadolinium-enhancing ring lesions were demonstrate in the white matter of the cerebrum, brainstem and cerebellum on day 17 of the illness, all appearing simultaneously as part of a monophasic illness. A parietal lesion exerted mass effect. Needling and biopsy yielded no evidence of a pyogenic lesion, tumour or tuberculosis and showed vasculitis. There was insufficient material for myelin staining. Dexamethasone therapy lead to rapid improvement of the radiological lesions: MRI and CT on day 34 of the illness showed complete clearing of the lesions except for residual abnormality at the biopsy site.  相似文献   
66.
SM6是我国检测E1Tor霍乱弧菌是否带有溶源性噬菌体的指示菌株。江苏的6株E1Tor霍乱弧菌和SM6都属于噬菌体-生物分型的1d型,而在噬菌体分型中SM6为1/2型,江苏的6株菌株则为1/2/3型;霍乱毒素(CT)基因测定也表明两者的不同,SM6不含CT基因,江苏的6株都含有CT基因,显示噬菌体分型可将噬菌体-生物分型的型别进一步划分,SM6的特性也为霍乱的进一步研究提供了资料。  相似文献   
67.
目的:探讨螺旋CT血管造影(Spiral CT angiography,SCTA)技术,以期提高SCTA造影的质量。材料与方法:采用Somatom Plus 4螺旋CT扫描系统对10例病人行腹部SCTA检查。扫描技术和造影剂参数按病变范围和性质而定,三维重建采用最大强度投影法(MIP)或表面阴影显示法(SSD)或弯曲平面重建法(CPR)。结果:SCTA检查技术能可靠地显示血管形态和病变,评价腹部肿瘤与邻近血管关系。结论:SCTA是无创伤性的血管成像术,在很大范围可替代创伤性的血管造影。  相似文献   
68.
Twenty-nine patients with diffuse liver disease were examined by ultrasound, CT and MRI. MRI was performed using T1- and T2-weighted spin-echo sequences as well as fast gradient-echo-sequences. The paramagnetic contrast agent Gd-DTPA was applied intravenously (0.1 mmol/kg). in patients with hepatitis, MRI could be used in guiding liver biopsies as inflammatory changes were clearly delineated. CT and ultrasound were superior to MRI in the detection of focal or diffuse fatty degeneration. On the other hand MRI was more helpful in differentiating fatty changes and neoplasm. In liver cirrhosis, fibrotic changes were most clearly demonstrated by MRI. In patients suffering from hemochromatosis MRI offers advantages over CT and ultrasound in the diagnosis and follow up due to the paramagnetic properties of iron, resulting in a reduction in signal intensity. In patients with Wilson's disease a characteristic pattern of parenchymal changes was seen. Administration of Gd- DTPA contributes additional information about perfusion conditions in the liver parenchyma, however this information was not of diagnostic relevance in the cases we studied. Correspondence to: T.J. Vogl  相似文献   
69.
Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and cranial CT parameters were examined at the end of the 3 months interval on each pressure level.The patients improved within the first 3 months inspite of an unchanged mean intracranial pressure and remained in a stable clinical condition during the rest of the study period. The intracranial pressure was significantly reduced at 9 months. The ventricular index, Evans index, temporal horn and third ventricle width were reduced 3 months post-operatively and did not change significantly during the rest of the study. The pre-operative third ventricle width was correlated to high psychometric test results after shunt surgery. Reduction in ventricular index, Evans index and third ventricle width after surgery correlated to improvement in psychometric scoring.The clinical improvement after shunt surgery for normal pressure hydrocephalus is seen within 3 months and is independent of the adjusted valve pressure.  相似文献   
70.
本文报告了两例脊髓萎缩,并结合文献复习讨论了该病的好发部位、病因、临床表现、诊断和治疗。脊髓萎缩的病因多为继发性,也可为特发性。根据临床表现结合脊髓CT造影及MRI检查,可以明确诊断。  相似文献   
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