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81.
目的 对 12例患者的CT引导下经肋间隙穿刺活检操作方法和临床价值进行总结。方法 选择 2 0 0 0年 1月至 2 0 0 2年 6月 12例CT引导下经肋间隙穿刺患者 ,并经病理细胞学及组织学证实。结果 所有 12例患者在CT引导下穿刺均获得成功 ,11例取得较满意的细胞学及组织学材料 ;有 1例发生并发症。结论 CT引导下经肋间隙穿刺活检准确率较高 ,并发症较低 ,安全、可靠 ,是一种先进科学的检查方法  相似文献   
82.
实验性脑脓肿影像学改变的病理基础研究   总被引:16,自引:0,他引:16  
目的:明确不同时期动物脑脓肿的影像学特征及其相应的病理学改变。方法:制备脑脓肿狗动物模型14只,采用CT、MRI检查结合多项病理学观测进行动态分析。结果:脑炎期MRI对炎症坏死区及水肿范围的显示较CT扫描更为清晰准确。包膜形成期:CT上脑脓肿包膜强化是炎症区血脑屏障破坏和新生血管形成所致;MRIT2加权成像上包膜的低信号“暗带”与包膜上的巨噬细胞堆积有关,延迟扫描和MRI均能有效地区分脑脓肿的急性脑炎期和包膜形成期,但MRI更加准确、迅速。结论:脑脓肿的MRI特征与其临床分期及病理学变化的相关性较好,能更加准确、简便、迅速地区别脓肿的脑炎期和包膜形成期,可作为临床诊治脑脓肿的有力参考。  相似文献   
83.
Mucins have a polypeptide backbone, oligosaccharide side-chains and peripheral structures that include sialic acids. Several pathogens have specific receptors for sialic acids, including human strains of influenza A virus which preferentially recognise and bind α2-6 linked rather than α2-3 linked sialic acids.1 1 NElson J., COuceiro S.S., PAulson J.C. & BAum L. (1993) Influenza virus strains selectively recognise sialyloligosaccharides on human respiratory epithelium; the role of the host cell in selection of haemagglutinin receptor specificity. The aim of this study was to identify possible disease-related changes in the expression of sialic acids in nasal mucins. Nasal mucosal samples were placed in organ culture. Metabolically-labelled mucins were purified by gel filtration, blotted on to nitrocellulose membranes and probed with the sialic acid-binding lectins Sambucus nigra and Maackia amurensis. Ninety-five mucosal samples were collected (49 turbinates, 31 nasal polyps, 15 samples from FESS). Lectin binding, expressed as optical density, showed significantly increased binding of S. nigra to cellular (P = 0.02; Kruskal–Wallis) and secreted (P = 0.045) mucin from allergic mucosa compared to non-allergic mucosa. No significant differences were found in the binding patterns of M. amurensis. This study has demonstrated increased expression of α2-6 linked sialic acids in the mucins synthesised and secreted by allergic compared to non-allergic nasal mucosa. This may cause a change in the way mucins and pathogens interact in allergic rhinitis, leading to altered susceptibility to upper respiratory tract infection.  相似文献   
84.
Although endoscopic procedures with tissue biopsy are the mainstay in the evaluation of laryngeal lesions, radiological imaging studies remain important. Computerized tomography (CT), magnetic resonance imaging (MRI) and ultrasound (US) are the most reliable methods, especially for deep laryngeal compartments, cartilage, extralaryngeal structures and neck nodes. However, the larynx is a difficult organ for radiological imaging because respiration and swallowing can cause several artifacts and distort image. In this report we studied the role of a spiral CT technique and compared this with conventional CT in 32 patients. We used the Hitachi W950SRBT machine and took both conventional and spiral sections of the larynx and neck in all 32 patients. The scans were taken with a 5-mm table motion and 5-mm section thickness in both studies. In the spiral technique the raw data acquired were used retrospectively for 2-mm and 5-mm reconstructions. Anatomic details, motion artifacts and vascular enhancements were compared by a scoring system. The mean values were then analyzed statistically by the paired t-test. The average examination time was 3 min 18 s for conventional CT and 28 s for spiral CT. Anatomic detail scores were better in the 2-mm section spiral CT studies compared to 5-mm section spiral and conventional CT groups. Motion artifact scores were better in the 2-mm and 5-mm spiral CT groups compared to the 5-mm conventional CT group. Vascular enhancement scores were better in the spiral CT group. Overall, the thinner (2-mm) sections of the spiral CT studies further improved image quality regarding both anatomic details and motion artifacts. Scanning time for spiral CT was very short, motion artifacts were less, and vascular enhancement and anatomic details were better. Volumetric data could also be reconstructed for thinner sections in all planes retrospectively for further evaluation. Our findings showed that spiral CT was a better method than conventional CT for evaluating laryngeal lesions. Received: 4 December 1996 / Accepted: 18 August 1997  相似文献   
85.
We present a 70-year-old woman with pre-B acute lymphoblastic leukemia in whom serial imaging studies showed the development of multiple vertebral collapse, and communicating superior and inferior Schmorl’s nodes creating a longitudinal channel (”tunneling” Schmorl’s nodes) through the anterior aspect of T12 to L3 vertebral bodies of her osteoporotic thoracolumbar spine. This was observed after achieving complete remission of the disease and during maintenance therapy. The finding is felt to be secondary to iatrogenic exacerbation of osteoporosis. Received: 26 May 2000 Revision requested: 23 June 2000 Revision received: 10 July 2000 Accepted: 13 July 2000  相似文献   
86.
目的:研究基因CT120在胶质瘤组织中的表达及其与胶质瘤组织病理学的关系。方法:应用免疫组织化学方法检测50例胶质瘤手术切除标本、3例正常脑组织中CT120蛋白的表达:应用半定量RT—PCR检测20例胶质瘤、3例正常脑组织中CT120mRNA的表达。结果:免疫组织化学检测发现正常脑组织中CT120蛋白无表达.50例胶质瘤组织中CT120蛋白表达阳性率为50.9%,不同级别胶质瘤中的表达无显著差异(χ^2=2.99,P〉0.05);半定量RT—PCR检测正常脑组织中CT120 mRNA呈弱表达,不同病理级别胶质瘤CT120 mRNA表达无显著差异(χ^2=3.25.P〉0.05)。结论:基因120在胶质瘤有表达,但在胶质瘤发生发展中作用不明显。  相似文献   
87.
The aim of this study was to evaluate the accuracy of dynamic CT in the preoperative staging of gastric cancer. One hundred seven patients affected by gastric cancer diagnosed by endoscopic biopsy were prospectively staged by dynamic CT prior to tumor resection. After an oral intake of 400–600 ml of tap water and an intravenous infusion of a hypotonic agent, 200 ml of non-ionic contrast agent were administered by power injector using a biphasic technique. The CT findings were prospectively analyzed and correlated with the pathological findings at surgery. The accuracy of dynamic CT for tumor detection was 80 and 99 % in early and advanced gastric cancer, respectively, with overall detection rate of 96 % (103 of 107). Three early (pT1) and one advanced (pT2) cancers were undetected. Tumor stage as determined by dynamic CT agreed with pathological findings in 83 of 107 patients with an overall accuracy of 78 %. The accuracy of CT in detecting increasing degrees of depth of tumor invasion when compared with pathological TNM staging was 20 % (3 of 15) and 87 % (80 of 92) in early and advanced cancer, respectively. The sensitivity, specificity, and accuracy of CT in the preoperative staging (pT3–pT4 vs pT1–pT2) was 93, 90, and 91.6 %, respectively. The sensitivity, specificity, and accuracy of CT in assessing metastasis to regional lymph nodes was 97.2, 65.7, and 87 %, respectively. Computed tomography correctly staged liver metastases in 105 of 107 patients with an overall sensitivity of 87.5 % and specificity of 99 %. The sensitivity of peritoneal involvement was 30 % when ascites or peritoneal nodules were absent. Our findings show that dynamic CT can play a role in the preoperative definition of gastric cancer stage. The results can be used to optimize the therapeutic strategy for each individual patient prior to surgery, thus avoiding unnecessary intervention and allowing careful planning of extended surgery in eligible patients. Received: 29 June 1999, Revised: 20 October 1999, Accepted: 22 May 2000  相似文献   
88.
After we incidentally found on CT extensive esophageal fat accumulations in a patient with long-term use of steroids, we prospectively evaluated during a 6-month period all CT studies of the chest for esophageal lipomatosis and related the findings to the possible use of steroids. The diagnosis of esophageal fat on CT was made by density measurements or if too small for reliable density measurements by comparison with mediastinal fat. In 21 of 1320 exclusively older male patients the diagnosis of esophageal lipomatosis was definite in 7 and likely in 14 patients. All fat accumulations were located in the upper third of the esophagus (mean length 22 ± 6 mm) and presented ring-like (n = 10), irregular (n = 3), or as a horseshoe sparing the posterior border (n = 8). In 20 patients there was an unequivocal history of steroid treatment. Associated centripetal fat infiltration was found in 11 patients. None of the patients had swallowing problems. Prolonged use of steroids, either orally or inhalationally administered, is associated with esophageal lipomatosis. The predisposition for the upper esophagus might be related to the presence of striated muscle cells in this part of the esophagus; moreover, inhalational steroid therapy may adversely affect the upper esophagus. Received: 3 April 2000; Accepted: 2 May 2000  相似文献   
89.
Computed tomography scans, including thin-section high-resolution computed tomography (HRCT), occasionally fail to differentiate between small non-cancerous nodules from lung cancers. We describe nine such lesions ( < 20 mm in diameter) initially identified through our screening program for lung cancer using CT scanning. Pathological diagnoses included nodular fibrosis (n = 4), granuloma (n = 1), cryptococcoma (n = 1), localised organising pneumonia (n = 1), inflammatory pseudo-tumour (n = 1) and sclerosing haemangioma (n = 1). High-resolution CT findings, together with MRI findings with contrast-enhanced dynamic studies, were retrospectively evaluated. Additional cases should be identified and radiologically characterised in order to reduce the number of non-cancerous tumours that are treated by unnecessary surgery. Received: 28 February 2000; Accepted: 29 February 2000  相似文献   
90.
Imaging of blunt chest trauma   总被引:13,自引:0,他引:13  
In western European countries most blunt chest traumas are associated with motor vehicle and sport-related accidents. In Switzerland, 39 of 10,000 inhabitants were involved and severely injured in road accidents in 1998. Fifty two percent of them suffered from blunt chest trauma. According to the Swiss Federal Office of Statistics, traumas represented in men the fourth major cause of death (4 %) after cardiovascular disease (38 %), cancer (28 %), and respiratory disease (7 %) in 1998. The outcome of chest trauma patients is determined mainly by the severity of the lesions, the prompt appropriate treatment delivered on the scene of the accident, the time needed to transport the patient to a trauma center, and the immediate recognition of the lesions by a trained emergency team. Other determining factors include age as well as coexisting cardiac, pulmonary, and renal diseases. Our purpose was to review the wide spectrum of pathologies related to blunt chest trauma involving the chest wall, pleura, lungs, trachea and bronchi, aorta, aortic arch vessels, and diaphragm. A particular focus on the diagnostic impact of CT is demonstrated. Received: 29 November 1999; Accepted: 28 January 2000  相似文献   
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