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91.
分析了60例垂体腺瘤的CT表现。1例垂体微腺瘤缺乏特异性征象,59例大腺瘤大多数表现典型,诊断依据为肿瘤位置和蝶鞍改变。垂体腺瘤的形态学表现无特异性。应加强对垂体瘤卒中和侵袭征象的认识。对成人鞍区肿瘤的鉴别诊断进行了简短讨论。  相似文献   
92.
A S9-2 computerized gait analysis system developed by us is reported. The advantages of the system are: synchronous measurement of the forces, angles and time parameters; high efficiency, accuracy and good repeatability; low cost and easy to operate. A three dimensional analysis of the foot-ground reaction forces of 41 normal subjects during level walking was carried out by the S9-2 system and a series of normal values of parameters and characteristic curves were obtained. The mechanism of formation of the parameters and curves and the sex influence were investigated and discussed. In old subject, before the development of "cautious gait", most values of the parameters did not differ significantly from those of the young subjects, except that the centre of gravity of the body crossing the hip earlier with a slight decrease in the medio-lateral balance capacity.  相似文献   
93.
Poorly differentiated adenocarcinoma of the nasopharynx is not rare. It comprises 5% of all nasopharyngeal carcinomas. In this paper, specimens of 41 cases of poorly differentiated adenocarcinoma of the nasopharynx were studied. The microscopic findings have the tendency to form glandular or duct-like structures, or a specific "cerebriform" appearance, AB-PAS stain was positive. In addition to the common features of adenocarcinoma (cancer cells vary in size, with large, round central nuclei, enlarged conspicuous nucleoli), a specific feature that the nuclei of cancer cells were 1-2 times larger than those of normal cells was seen in smear. Electron microscopic observation revealed that the cytoplasm of the cancer cells contained numerous mitochondria, RER, developed Golgi apparatus and some secretory granules. Immunocytochemical studies proved that it was moderately positive for immunostain of low molecular weight keratin protein (K10,11), but was negative for keratin (K) it is different from poorly differentiated squamous cell carcinoma and vesicular nuclear cell carcinoma, of which were strongly positive or partially positive for keratin. The main points of differential diagnosis for these carcinomas are elucidated.  相似文献   
94.
目的 研究血清甲状腺球蛋白(Tg)、甲状腺球蛋白抗体(TgAb)对甲状腺癌根治术联合131I治疗后随访期间复发/转移的评估价值。方法 回顾性分析2018年6月—2020年6月中国贵航集团三〇二医院收治的106例分化型甲状腺癌患者的临床资料,患者均接受甲状腺癌根治术治疗,术后均采用131I进行清除残留的甲状腺组织(清甲)治疗。随访24个月,将患者分为复发转移组(21例)和未复发转移组(85例)。比较两组临床资料、131I治疗情况及血清促甲状腺激素(TSH)、Tg、TgAb。绘制受试者工作特征(ROC)曲线分析血清Tg、TgAb检测对甲状腺癌根治术联合131I治疗后复发/转移的预测价值。采取非条件一般Logistic回归模型进行多因素分析。结果 与未复发转移组比较,复发转移组原位肿瘤T4分期、手术方式为腺叶切除或近全切、残余甲状腺质量≥1 g、手术至131I治疗时间> 3个月、24 h摄131I率≤ 20%患者的占比均较高(P <0.05);复发转移组血清Tg和TgAb水平均较高(P <0.05);ROC曲线分析结果显示:血清Tg预测甲状腺癌根治术联合131I治疗后复发或转移的最佳截断值为1.674 μg/L,AUC为0.803(95% CI:0.721,0.884),敏感性为81.1%(95% CI:0.724,0.898),特异性为63.8%(95% CI:0.585,0.691);血清TgAb预测的最佳截断值为44.19 3 IU/mL,AUC为0.911(95% CI:0.859,0.963),敏感性为89.2%(95% CI:0.813,0.971),特异性为72.5%(95% CI:0.674,0.774)。非条件Logistic一般回归分析结果显示:原位肿瘤T4分期[O^R=2.916(95% CI:1.325,6.417)]、腺叶切除或近全切[O^R=3.243(95% CI:2.174,4.838)]、残余甲状腺质量≥ 10 g[O^R=1.835(95% CI:1.514,2.224)]、手术至131I治疗时间> 3个月[O^R=1.962(95% CI:1.371,2.808)]、24 h摄131I率≤ 20%[O^R=2.638(95% CI:1.219,5.709)]、血清Tg ≥ 1.674 μg/L[O^R=2.503(95% CI:1.430,4.360)]、血清TgAb≥ 44.193 IU/mL[O^R=2.944(95% CI:2.016,4.299)]可能是甲状腺癌根治术联合131I治疗后复发或转移的危险因素(P <0.05);风险因素预测模型预测甲状腺癌根治术联合131I治疗后复发/转移的ROC曲线下面积为0.961(95% CI:0.935,0.987),标准误为0.010,临界值为73.162,敏感性为91.9%(95% CI:0.863,0.957),特异性为88.2%(95% CI:0.845,0.922)。结论 甲状腺癌根治术联合131I治疗后出现复发/转移的患者血清Tg、TgAb水平明显升高,Tg、TgAb对预测复发/转移具有较好的价值,联合其他危险因素建立风险因素预测模型可进一步提高预测价值。  相似文献   
95.
Knudson's two-hit hypothesis postulates that genetic alterations in both alleles are required for the inactivation of tumor-suppressor genes. Genetic alterations include small or large deletions and mutations. Over the past years, it has become clear that epigenetic alterations such as DNA methylation are additional mechanisms for gene silencing. Restriction Landmark Genomic Scanning (RLGS) is a two-dimensional gel electrophoresis that assesses the methylation status of thousands of CpG islands. RLGS has been applied successfully to scan cancer genomes for aberrant DNA methylation patterns. So far, the majority of this work was done using NotI as the restriction landmark site. Here, we describe the development of RLGS using AscI as the restriction landmark site for genome-wide scans of cancer genomes. The availability of AscI as a restriction landmark for RLGS allows for scanning almost twice as many CpG islands in the human genome compared with using NotI only. We describe the development of an AscI-EcoRV boundary library that supports the cloning of novel methylated genes. Feasibility of this system is shown in three tumor types, medulloblastomas, lung cancers, and head and neck cancers. We report the cloning of 178 AscI RLGS fragments via two methods by use of this library.  相似文献   
96.
97.
98.
基于Client/Server结构的医院图像处理系统   总被引:1,自引:0,他引:1  
作者介绍了一种医院图像处理系统,可将医院的各种设备所产生的医疗图象资料,动用先进的可读写光盘为存储介质有效地进行存储,再通过通信网络及时地传送到医院的各个部门,辅助医生进行临床诊断及科研,提高有关科室及整个医院的工作效率及经济效益。  相似文献   
99.
8例胶质瘤病例,标本分别取自同一病例的瘤体,瘤周水肿区和邻近脑组织。瘤体和瘤周水肿区血脑屏障超微结构变化无明显差异,内皮肿胀,毛细血管腔狭小,腔面有稀疏的绒毛样突起,内皮为无孔型,胞质内胞饮泡较多,内皮紧密连接增长,细胞连接间隙增宽,基膜完整,基膜完整,胶质膜缺损。  相似文献   
100.
Kim J  Yin FF  Zhao Y  Kim JH 《Medical physics》2005,32(4):866-873
A rigid body three-dimensional/two-dimensional (3D/2D) registration method has been implemented using mutual information, gradient ascent, and 3D texturemap-based digitally reconstructed radiographs. Nine combinations of commonly used x-ray and computed tomography (CT) image enhancement methods, including window leveling, histogram equalization, and adaptive histogram equalization, were examined to assess their effects on accuracy and robustness of the registration method. From a set of experiments using an anthropomorphic chest phantom, we were able to draw several conclusions. First, the CT and x-ray preprocessing combination with the widest attraction range was the one that linearly stretched the histograms onto the entire display range on both CT and x-ray images. The average attraction ranges of this combination were 71.3 mm and 61.3 deg in the translation and rotation dimensions, respectively, and the average errors were 0.12 deg and 0.47 mm. Second, the combination of the CT image with tissue and bone information and the x-ray images with adaptive histogram equalization also showed subvoxel accuracy, especially the best in the translation dimensions. However, its attraction ranges were the smallest among the examined combinations (on average 36 mm and 19 deg). Last the bone-only information on the CT image did not show convergency property to the correct registration.  相似文献   
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