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21.
22.
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   
23.
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   
24.
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   
25.
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   
26.
27.

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   
28.
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   
29.

BACKGROUND.

The ThinPrep Imaging System (TIS) has been approved by the U.S. Food and Drug Administration for use to decrease the number of false‐negative results in ThinPrep (TP) gynecologic specimens and increase cytotechnology productivity. Although the increased detection of squamous abnormalities using the TIS has been well documented, to the authors' knowledge, data regarding the impact of the TIS in the detection of glandular abnormalities is limited. The goal of the current study was to evaluate the effectiveness of the TIS in detecting glandular abnormalities in cervicovaginal specimens.

METHODS.

TIS evaluated TP tests with histologic confirmation of adenocarcinoma involving the gynecologic system were included in the current study. Two cytotechnologists independently reviewed the cases for the presence or absence of atypical glandular cells. Review results were correlated with initial cytologic and histologic diagnoses.

RESULTS.

A total of 124 cases met the criteria for inclusion in the current study. Seventy of these cases (56%) were found to contain atypical glandular cells on the TP slide. TIS was able to identify atypical cells in 97% of these cases (68 of 70 cases). Nine cases initially reported as benign were found to contain atypical glandular cells on secondary review. All but 1 of these cases contained atypical glandular cells detected by the TIS. The majority of these false‐negative cases (6 of 9 cases) derived from endometrial adenocarcinoma. No cytologic evidence of a glandular abnormality was found in the 54 remaining cases.

CONCLUSIONS.

The TIS was found to be effective in identifying atypical glandular cells in specimens containing malignant glandular cells, leading to a full review of the slide. Cancer (Cancer Cytopathol) 2008. © 2007 American Cancer Society.  相似文献   
30.
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