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31.
Robert Terkeltaub Andrea J. Tenner Franklin Kozin Mark H. Ginsberg 《Arthritis \u0026amp; Rheumatology》1983,26(6):775-783
Using 2-dimensional O'Farrell gel electrophoresis, we have mapped the proteins from undiluted plasma and serum which bind to monosodium urate (MSU) crystals. More than 30 crystal-associated polypeptides were visualized, including anionic and cationic species. Proteins increased on the crystals relative to plasma included C1q, C1r, C1s, fibronectin, fibrinogen, and kininogen. Crystal-bound polypeptides derived from IgG, albumin, and transferrin were recovered in decreased amounts relative to plasma. Direct evidence for activation of the complement and coagulation systems in plasma was provided by the identification of crystal-associated activation fragments of C1 and kininogen. Plasmas deficient in selected proteins (e.g., C1q and IgG) were used to define the role of these proteins in such activation events and confirmed activation of C1 in immunoglobulin-deficient plasma by MSU crystals. In summary, we have described a high resolution, semi-quantitative approach to analyze protein binding to crystals, have documented the complexity of crystal-plasma protein interaction, and have provided direct evidence for the binding of coagulation system proteins and binding and activation of complement by MSU crystals, in whole plasma and IgG-deficient plasma. 相似文献
32.
运动性心律失常是指发生于机体剧烈运动期间或之后的心律失常。临床表现不一,从心悸、头晕、晕厥、心绞痛、急性心肌梗死和充血性心力衰竭,甚至到心脏性猝死。运动性心律失常可见于心肌缺血,如患有动脉粥样硬化性心脏病以及患有原发性或继发性心肌病的患者。然而,也可能发生在似乎健康的个体。在后一组人群中,运动性心律失常可以是良性的,但也可以是获得性(如药物诱发)或先天性(如先天性长QT综合征或致心律失常性右室发育不良)心电活动或结构的异常而呈恶性。这种潜在病理生理学机制的复杂性,使运动性心律失常的诊断和治疗成为临床医学上的… 相似文献
33.
Cytopathological and immunocytochemical findings of pancreatic anaplastic carcinoma with ZEB1 expression by means of touch imprint cytology 下载免费PDF全文
Yoshiki Naito MD PhD Akihiko Kawahara CFIAC PhD Tomoki Taira CT Yorihiko Takase CT Kazuya Murata CT PhD Yusuke Ishida MD PhD Yoshinobu Okabe MD PhD Masahiko Tanigawa MD Yutaro Mihara MD Masamichi Nakayama MD PhD Kazuhide Shimamatsu MD PhD Hirohisa Yano MD PhD Jun Akiba MD PhD 《Diagnostic cytopathology》2018,46(2):198-203
Pancreatic anaplastic carcinoma (PAC) is rare and has an aggressive clinical course. We report an autopsy case of PAC focusing on the cytopathological characteristics of the tumor and immunocytochemical staining for vimentin, E‐cadherin, and zinc finger E‐box binding homeobox 1 (ZEB1), which markers are associated with epithelial markers of epithelial‐mesenchymal transition (EMT). A 50‐year‐old woman presented to our hospital with a chief complaint of jaundice. A pancreatic head tumor and multiple liver nodules were detected on abdominal computed tomography. Biliary cytology under endoscopic retrograde cholangiopancreatography suggested ductal adenocarcinoma. Three months after admission, she died of multiorgan failure. At autopsy, touch imprint cytology using squash preparation of the pancreatic tumor identified two different cell types; numerous isolated malignant cells with large and pleomorphic nuclei and a few clusters showing irregularly overlapped nuclei and irregular contours within the necrotic background. Immunocytochemically, isolated cells were positive for vimentin and ZEB1, and negative for E‐cadherin. Conversely, clusters were negative for vimentin and ZEB1, and positive for E‐cadherin. Histologically, the tumor was composed of sarcomatous cells with small foci of adenocarcinoma, which were consistent with a diagnosis of PAC. Immunohistochemical staining of the adenocarcinoma and sarcomatous cells corresponded to those of the clusters and isolated malignant cells, respectively. Immunostaining of these EMT markers is useful to distinguish sarcomatous cells from adenocarcinoma and can contribute to the accurate diagnosis of pancreatic tumors with EMT. 相似文献
34.
实时灰阶超声造影和螺旋CT诊断肝肿瘤的比较研究 总被引:26,自引:2,他引:26
目的比较实时超声造影和螺旋CT显示肝肿瘤血流信号的特点.方法对29例肝肿瘤(原发性肝癌16例,转移性肝癌2例,血管瘤6例和肝局灶性结节增生5例)分别进行超声造影和CT检查.结果超声造影显示肝恶性肿瘤的整体型、血管瘤的周边型及局灶性结节增生的中央型出现率显著高于其他病变(P<0.01).CT示恶性肿瘤中94.4%(17/18) 动脉期强化、门脉期低密度;血管瘤中83.3%(5/6)呈结节状强化;肝局灶性结节增生动脉期均明显强化.超声造影和CT鉴别肝肿瘤的能力无显著差异.结论超声造影和CT都能敏感地显示不同肝肿瘤的血供特征. 相似文献
35.
螺旋CT肝脏双期扫描及门静脉血管三维重建在小肝癌诊断的临床应用 总被引:3,自引:0,他引:3
目的 探讨螺旋CT肝脏双期扫描及门静脉血管三维重建在小肝癌诊断中临床应用价值。方法 25例直径≤3cm小肝癌行螺旋CT肝脏双期扫描及门静脉血管三维重建。三维重建方法采用最大强度投影(MIP)。结果 (1)CT平扫,18例病灶呈低密度,7例病灶呈等密度。肝动脉期,25例病灶强化呈高密度,强化类型分为均匀一致性,斑点状及环状强化。门静脉期25例病灶均呈低密度。(2)门静脉血管MIP三维重建能较好显示小肝癌病灶与肝内门静脉血管关系,肝内门静脉血管分支于病灶处稀少,部分中断或被轻度推移,肿瘤内无门静脉分支血管。结论 螺旋CT肝脏双期扫描及门静脉血管三维重建是诊断和评价小肝癌的有效方法,提高了小肝癌的检出率及诊断正确率,可较好显示病灶与门静脉的关系,为其外科手术提供导向。 相似文献
36.
目的:评价螺旋CT在诊断肺动脉栓塞中的作用。方法:16例肺动脉栓塞患者行螺旋CT肺动脉造影 (SCTA)检查,层厚3mm,扫描时间0.8s,对比剂注射速度3.5ml/s,总量100ml,扫描延迟时间15s。结果:16例 共644支,其中134支肺动脉及分支显示了栓塞,占20.8%。228支肺段肺动脉中,有56支显示肺动脉栓塞,占分 析肺动脉支的24.5%。204支亚段肺动脉中37支显示肺动脉栓塞,占分析肺动脉支15.4%。肺动脉栓塞的CT形 态:①直接征象为不同程度的肺动脉分支内充盈缺损。中心型充盈缺损17支,偏心型充盈缺损44支,附壁血栓型 34支,完全阻塞型39支。②间接征象胸膜下肺梗死灶,内乳动脉一侧增粗,肺纹理稀少,胸水,肺动脉高压。结论: 螺旋CT肺动脉造影是诊断肺动脉栓塞的快速、有效、无创伤的诊断方法。 相似文献
37.
38.
Michael Thrall MD Klint Kjeldahl CT H. Evin Gulbahce MD Stefan E. Pambuccian MD 《Cancer cytopathology》2007,111(4):217-223
BACKGROUND.
In addition to the reporting of atypical glandular cells (AGC) and adenocarcinoma (ADCA), the 2001 Bethesda System requires the reporting of benign‐appearing endometrial cells in women aged >40 years (BAEMC). In this study, the authors evaluated the contribution of each of these reporting categories to the sensitivity and specificity of a liquid‐based Papanicolaou test for endometrial carcinoma or hyperplasia.METHODS.
Over the 3‐year study period, in the setting of a large, multihospital health care system, the authors analyzed the results from liquid‐based Papanicolaou tests that were performed within the 6 months that preceded a histologic diagnosis of endometrial carcinoma or hyperplasia and that were reported according to the 2001 Bethesda System.RESULTS.
Two hundred seventy‐two women had a histologic diagnosis of endometrial hyperplasia (n = 199) or malignancy (n = 73) within 6 months after a Papanicolaou test. In total, 188,594 Papanicolaou tests (91,385 from women aged >40 years) were interpreted during the study period and resulted in 3810 diagnoses of BAEMC, 326 diagnoses of AGC, and 30 diagnoses of ADCA. Only 28 of 73 women (38.4%) with endometrial carcinoma had cytologically AGC or ADCA reported on a previous Papanicolaou test. The reporting of BAEMC increased this sensitivity by only 5.5% (4 additional tests) but decreased the specificity of the Papanicolaou test for endometrial malignancy from 99.8% to 96%. For endometrial hyperplasias, the sensitivity of the Papanicolaou test was even lower (39 of 198 tests; 19.7%), but BAEMC represented the majority of endometrial‐type cells reported (36 of 39 tests).CONCLUSIONS.
The reporting of BAEMC led to an only marginal increase in sensitivity that had to be weighed against the significant loss in specificity of the Papanicolaou test for endometrial neoplasia. Cancer (Cancer Cytopathol) 2007. © 2007 American Cancer Society. 相似文献39.
目的着重探讨45例缺血性肠病患者的病因、CT检查技术及其影像表现。资料与方法45例缺血性肠病均经螺旋CT扫描。26例经过手术证实,14例经过治疗痊愈,5例急性死亡。结果其中肠系膜动脉缺血24例,肝固有动脉缺血4例,肠系膜静脉缺血17例。结论严格掌握CT检查技术,根据CT影像表现并密切结合临床,对缺血性肠病患者可以作出确定诊断。 相似文献
40.
Maria A. Friedlander MPA CT CMIAC Dorota Rudomina MBA CT Oscar Lin MD PhD 《Cancer cytopathology》2008,114(1):7-12