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991.
Background We investigated retrospectively the records and tissue samples of patients with primary ovarian transitional cell carcinoma to determine clinical and pathologic features. Methods The records of 3 patients with ovarian transitional cell carcinoma were reviewed using data from several imaging techniques: transvaginal ultrasound, computed tomography, and magnetic resonance imaging. We also determined levels of several tumor marker molecules; and the level of carbohydrate antigen 125 (CA 125), was examined by means of immunohistochemistry. Results The tumors of 2 patients were classified as pure trnasitional cell carcinoma; in the remaining patient, as predominantly transitional cell carcinoma. All tumors were bilateral, and 2 of the 3 tumors formed solid masses. Areas of irregular high intensity signals were seen in magnetic resonance images of the solid parts of the tumors. All 3 tumors tested positive for CA 125; histochemical expression was confined to the tumor cell membrane and/or the cytoplasm in all cases. The tumors of all 3 patients tested negative for carcinoembryonic antigen (CEA), and second-look laparotomies did not reveal any residual neoplasms in any of the patients. The patients have been in a disease-free state for 34, 42, and 14 months, respectively. Conclusion Our results suggest that transitional cell carcinomas tend to arise bilaterally and to form solid tumors. Magnetic resonance imaging was a useful diagnostic modality in these cases. Transitional cell carcinoma was characterized by the presence of CA 125 and the absence of CEA.  相似文献   
992.
目的:探讨食管癌和胃癌MRI检查的价值。方法:对95例食管癌和胃癌的MRI表现进行分析。结果;MRI所见与手术病理符合率以食管癌侵犯胸主动脉为最高。结论:MRI显示脏外生长型食管癌和胃癌具有较大价值;MRI显示病变波及范围、浸润破坏程度、与周围脏器的关系及有无转移等有较大优越性。  相似文献   
993.
目的:探讨肺癌核素显像^99mTc-MIBI滞留分数与P糖蛋白(Pgp)、增殖细胞核抗原(PCNA)和胎盘型谷胱甘肽-S-转移酶(GST-π)的关系。方法:12例肺癌病人术前分别作肺部早期和延迟^99mTc-MIBI断层显像,计算肿瘤部位^99mTc-MIBI滞留分数,与手术后肿瘤标本测定的Pgp、PCNA、GST-π水平作相关分析。结果:^99mTc-MIBI滞留分数与Pgp明显负相关(r=-0  相似文献   
994.
为探讨蝶窦变的像学诊断与垂体功能异常的关系,分析7例垂体功能异常的蝶窦病变的影像学表现;结果示7例垂体功能异常者重体影像均异常,  相似文献   
995.
Electron spectroscopic imaging (ESI) was used to analyze the element content of melanin granules in the stria vascularis seen in ultrathin sections of Spurr-embedded cochleae of the guinea pig. To determine element composition, ESI images were taken at different ionization edges, and non-specific background signals were subtracted digitally by an image processing system. The presence of calcium and nitrogen in the melanin granules could be demonstrated clearly. The calcium identified in the melanin granules was then compared with the spatial distributions of calcium binding sites after the application of an antimonate precipitation method, which was used to localize loosely bound calcium. Despite a high calcium concentration within the granules, only very small single scattered calcium precipitates could be detected between these structures as compared with the amount of calcium precipitates attached to the plasma membrane or located within the cell nuclei. The nearly complete absence of precipitates within the melanin granules after the application of antimonate suggests differences in calcium binding and mobility involved in various physiological processes of ion balance regulation within the stria vascularis. Received: 14 October 1997 / Accepted: 11 February 1998  相似文献   
996.
Primary carcinoma of the fallopian tube is extremely rare and the preoperative diagnosis is often misdiagnosed as an ovarian carcinoma. We report a patient with primary carcinoma of the fallopian tube, strongly suspected preoperatively on the basis of characteristic clinical symptoms, elevated CA125 levels, and transvaginal sonography, computed tomography, and magnetic resonance imaging findings. The histology of fallopian tube carcinoma was demonstrated as transitional cell carcinoma. Extensive review of the literature showed that our case seemed to be the 14th case of primary transitional cell carcinoma of the fallopian tube.  相似文献   
997.
彩色多普勒组织显像在小儿病毒性心肌炎诊断中的应用   总被引:3,自引:0,他引:3  
本文报告用彩色多普勒组织显像(DTI)测定正常小儿173名,病毒性心肌炎40例,发现DTI在正常小儿的规律。病毒性心肌炎二尖瓣环舒张早期运动速度(MVR-DeV)显著低于正常儿童,40例病毒性心肌炎MVR-DeV降低者占72.5%,经过治疗后MVR-DeV90%以上短期内恢复正常。MVR-DeV降低率显著高于心脏解剖、心功能、心脏血流参数、心电图和心肌酶的异常率。因此,MVR-DeV对病毒性心肌炎的诊断、病情了解以及疗效观察均有重要价值。  相似文献   
998.
目的评价MRI在喉癌术前T分期中的价值。方法对59例喉癌的MRI资料进行回顾性分期,并与纤维喉镜及手术病理对照。结果MRI对各期喉癌分期的准确性分别是:T1:95%(20/21),T2:88%(15/17),T3:85%(11/13)T4:100%(8/8)。纤维喉镜分期的准确性是:T1:91%(19/21),T2:88%(15/17),T3:47%(8/13),T4:13%(1/8)。结论MRI能准确判断会厌前间隙(PES)、喉旁间隙(PGS)浸润及软骨破坏,因而可显著提高喉癌术前分期的准确性,对临床治疗方案选择具有重要意义。  相似文献   
999.
目的评价原发性生长激素缺乏症患者的心功能状况,以探讨生长激素对心功能的作用。方法用平衡法核素心血池显像技术及运动试验,对32例儿童期诊断为垂体发育不良所致的生长激素缺乏症患者及10例正常健康儿童进行心功能评价。结果32例患者左心室总体射血分数和左心室舒张末期高峰充盈率明显低于正常健康组小儿;25例(78%)患者局部心室收缩功能降低;15例(47%)患者左心室总体收缩或(和)舒张功能降低;25例(78%)运动试验后出现心率改变、轻度ST段降低及T波改变。结论大部分生长激素缺乏症者在没有生长激素治疗的情况下,存在不同程度的心室收缩和舒张功能损害及心肌缺血和劳损。生长激素缺乏症者应尽早检测心功能、尽早给予生长激素治疗以预防成年后心血管疾病的发生  相似文献   
1000.
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging) in the evaluation of preinvasive and early invasive cancer of the cervix. Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated for tumor detection and compared with results of histologic examination of the surgical specimens. Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging, whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and 5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images. In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic MR imaging. Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced MR imaging.  相似文献   
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