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目的 探讨肺癌侵犯中央肺动脉继发肺低灌注的CT特征及其诊断价值。方法 对2 0例手术及病理证实的肺癌侵犯中央肺动脉 (cancerousinvasionofcentralpulmonaryarteriesinlungcancer,CICPA)患者术前肺血管DSA及增强螺旋CT(含高分辨率CT ,即HRCT)征象行前瞻性对照研究。根据DSA和CT胸膜下末梢肺动脉分布和数量变化 ,即肺血管征、肺毛细血管充盈度和肺实质强化后密度及时间 密度曲线变化 (即肺实质征 ) ,行两者间的盲法对照 ,统计学分析CT与DSA征象及其一致性 ,评估CT对CICPA继发肺低灌注的诊断价值。结果 2 0例手术病理证实的CICPA病例中 ,共3 0支肺叶动脉受累 ,DSA显示 90 % (2 7/3 0 )出现肺叶低灌注征象 ,CT诊断肺低灌注敏感度为 78%(2 1/2 7) ,特异度 10 0 % (3 /3 ) ,准确度 80 % (2 4/3 0 )。肺低灌注与CPA狭窄程度无明显相关性 (rs=0 40 ,P =0 0 73 )。CT与DSA的肺血管征一致性较好 (Kappa =0 69,P <0 0 0 1) ,而肺实质征一致性稍差 (Kappa =0 3 7,P =0 0 11)。结论 肺低灌注是肺癌侵犯中央肺动脉的常见表现 ,CT对其定性诊断具有重要价值 ,而定量判断有一定限度 相似文献
54.
多孔β-TCP/rhBMP-2人工骨在小鼠体内的诱导成骨和早期降解行为的研究 总被引:1,自引:0,他引:1
目的 将多孔β—磷酸三钙和重组人的骨形成蛋白—2复合物,植入小鼠肌肉内,观察复合物的骨诱导能力和早期降解行为。方法 将多孔β—磷酸三钙/人骨形成蛋白—2复合物植入25只小鼠右侧大腿后侧肌肉内,单纯多孔β—磷酸三钙植入左侧为对照,分别于72h、1、2、3、4周取材,进行组织学和扫描电镜观察。结果 72h可见幼稚软骨,1周见成熟软骨,2周见编织骨和少量板层骨,3周和4周成熟的板层骨生成,对照组则无骨或软骨生成。2周开始间充质细胞和纤维组织长入材料,3~4周将材料包裹分割,同时可见多核巨细胞反应及吞噬现象,这些是降解早期组织学改变。结论 多孔β—TCP/rhBMP—2复合人工骨显示了良好的生物相容性,有强大的骨诱导能力,有希望作为新型骨移植替代材料用于临床。 相似文献
55.
Japanese encephalitis after a two-week holiday in Bali 总被引:2,自引:0,他引:2
W B Macdonald A R Tink R A Ouvrier M A Menser L M de Silva H Naim R A Hawkes 《The Medical journal of Australia》1989,150(6):334-6, 339
Japanese encephalitis is described in a 10-year-old girl after a short holiday in Bali. Four days after returning to Australia the patient presented with a high fever, stupor and rapidly-developing focal neurological signs. Recovery occurred gradually over a period of three months and she has returned to school. Japanese encephalitis viral infection was confirmed by a marked rise in specific haemagglutination-inhibition antibodies and the presence of immunoglobulin M antibodies to the flavivirus group. It is important to be aware of the possibility of arboviral infection in patients with encephalitis. In view of the recent outbreaks of Japanese encephalitis in Asia, travellers to the region should be warned to protect themselves from mosquito-bites. 相似文献
56.
Ana Cecília Montes Gil Raquel Lorenzetti Gun Bergsten Mendes André Moreno Morcillo Adyléia Aparecida Dalbo Contrera Toro Marcos Tadeu Nolasco da Silva Maria Marluce dos Santos Vilela 《Revista paulista de medicina》2007,125(4):205-209
CONTEXT AND OBJECTIVE: Adverse drug reactions are a significant problem in patients on antiretroviral therapy (ART). We determined liver enzyme elevation frequencies in HIV-infected children and adolescents receiving ART, and their association with risk factors. DESIGN AND SETTING: Cross-sectional study, at the Pediatrics Immunodeficiency Division, University Hospital, Universidade Estadual de Campinas. METHODS: Medical records of 152 children and adolescents (54.6% male; median age 7.48 years) were analyzed, with a mean of 2.6 liver enzyme determinations per patient. Clinically, patients were classified in categories N (6), A (29), B (78) and C (39). Serum levels of aspartate aminotransferase and alanine aminotransferase were evaluated. Hepatotoxicity was scored as grade 1 (1.1-4.9 times upper limit of normality, ULN), grade 2 (5.0-9.9 times ULN), grade 3 (10.0-15.0 times ULN) and grade 4 (> 15.0 times ULN). To assess hepatotoxicity risk factors, odds ratios (OR) and adjusted odds ratios (aOR) for age, gender, TCD4+ cell count, viral load and medication usage were calculated. RESULTS: We observed grade 1 hepatotoxicity in 19.7 % (30/152) patients. No cases of grade 2, 3 or 4 were detected. There was a significant association between hepatotoxicity and use of sulfonamides (OR, 3.61; 95% confidence interval (CI), 1.50-8.70; aOR, 3.58; 95% CI, 1.44-8.85) and antituberculous agents (OR, 9.23; 95% CI, 1.60-53.08; aOR, 9.05; 95% CI, 1.48-55.25). No toxicity was associated with ART. CONCLUSIONS: One fifth of patients experienced mild hepatotoxicity, attributed to antituberculous agents and sulfonamides. Our results suggest that ART was well tolerated. 相似文献
57.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
58.
Liviana Da Dalt Silvia Callegaro Silvia Carraro Barbara Andreola Massimo Corradi Eugenio Baraldi 《Pediatric allergy and immunology》2007,18(2):100-104
Respiratory syncytial virus (RSV) bronchiolitis is a very common infection in infants and, after the acute phase, a number of patients develop a reactive airway disease that lasts for years. Although the pathogenesis of the lung damage after RSV bronchiolitis is still largely unknown, previous studies suggest that leukotrienes may play an active part in it. The aim of this study was to measure leukotriene levels in the nasal lavage fluid (NLF) collected in infants during RSV bronchiolitis and 1 month later. Cysteinyl leukotrienes (Cys-LTs) and leukotriene B(4) (LTB(4)) were measured in the NLF of 22 infants with their first episode of RSV bronchiolitis and 16 healthy infants. A second NLF sample was collected to measure leukotriene levels 1 month after the acute disease. NLF Cys-LT levels were significantly higher in infants with RSV bronchiolitis than in healthy controls [950 pg/ml (285.5-2155.9) vs. 110.5 pg/ml (66.5-451.3), p = 0.01], and they remained so a month after the acute infection (p = 0.02). A subanalysis showed no difference in Cys-LTs concentrations, either between bronchiolitis infants with and without a family history of atopy, or between those with and without passive exposure to cigarette smoke. No significant difference was found between the LTB(4) levels measured in the bronchiolitis cases and the control children. Cys-LTs are significantly increased in the NLF of infants with acute RSV bronchiolitis, and remain so at 1-month follow-up, suggesting a possible role of these eicosanoids in the pathogenesis of the disease. 相似文献
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A total of 192 samples of serum from 113 Sri Lankan patients with clinical dysentery was examined for antibodies of the IgM class to the lipopolysaccharides (LPSs) of Shigella dysenteriae-1 and Escherichia coli O157:H7. By means of ELISA and immunoblotting, 59 patients were found to have serum antibodies to the LPS of S. dysenteriae-1 only. Four samples from one patient were found to contain serum antibodies to the LPSs of both S. dysenteriae-1 and E. coli 0157: H7. Antibodies to the LPS of S. dysenteriae-1 were also detected in 16 samples from 25 children, from Sri Lanka, with no previous history of dysentery; one of these children also had antibodies to the LPS of E. coli 0157: H7. Analysis of 16 samples from apparently healthy children in the U.K. showed that only one serum contained antibodies to the LPS of S. dysenteriae-1. This patient had a history of recent travel to Pakistan. The isolation of S. dysenteriae-1 remains the preferred test for the diagnosis of bacillary dysentery. The use of serology as a means of providing evidence of infection with S. dysenteriae-1, however may prove to be a useful adjunct to cultural techniques but needs to be validated in an area where this organism is endemic. 相似文献