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51.
目的:探讨β-catcnin在早期胃癌中的表达及其意义。方法:用免疫组织化学方法检测39例早期胃癌患者胃癌组织中β-catenin的表达情况。结果:39例早期胃癌中有20例存在β-catenin的异常表达,表现为细胞膜的表达缺失及细胞质和细胞核中表达增强。早期胃癌中β-catenin表达阳性率为51.28%。结论:在早期胃癌中存在β-catenin的异常表达,β-catenin的异常表达可能在早期胃癌的发生、发展中发挥重要的作用,可能是胃癌发生的一个早期事件。  相似文献   
52.
BACKGROUND: Myocardial perfusion single photon emission computed tomography (SPECT) occasionally fails to detect coronary stenosis in patients with coronary artery disease (CAD). We evaluated coronary flow reserve (CFR) using oxygen 15-labeled water in areas with and without ischemia on technetium 99m tetrofosmin stress perfusion SPECT in patients with angiographically documented CAD. METHODS AND RESULTS: Twenty-seven patients with CAD and eleven age-matched normal subjects were studied. Baseline myocardial blood flow (MBF) and MBF during hyperemia induced by intravenous adenosine triphosphate infusion (0.16 mg. kg(-1). min(-1)) were determined with the use of O-15-labeled water positron emission tomography, and the CFR was calculated. Tc-99m tetrofosmin stress/rest SPECT was performed for comparison. On the basis of the results of coronary angiography and SPECT, coronary segments were divided into 3 types: segments with coronary stenosis and a perfusion abnormality on stress SPECT imaging (group A, n = 16), segments with coronary stenosis without a perfusion abnormality (group B, n = 42), and remote segments with no coronary stenosis or perfusion abnormality (group C, n = 18). Baseline MBF values were similar among the 3 groups. CFR in group A was lower (1.82 +/- 0.54) than in group B (2.22 +/- 0.87, P <.05), in group C (2.92 +/- 1.21, P <.01), and in normal segments (3.86 +/- 1.24, P <.001). CFR in group B was lower than in group C (P <.02) and in normal segments (P <.001). CFR in group C was lower than in normal segments (P <.02). CONCLUSIONS: Areas with a perfusion abnormality on stress SPECT had reduced CFR. In the areas without a perfusion abnormality and with coronary stenosis, lowering of CFR was intermediate between the areas with a perfusion abnormality and remote segments. Moreover, CFR was slightly, but significantly, lower in remote segments in patients with CAD compared with normal segments.  相似文献   
53.
To clarify the genetic aberrations involved in the development and progression of hepatitis C virus-associated hepatocellular carcinoma (HCV-HCC), we investigated DNA copy number aberrations (DCNAs) in 19 surgically resected HCCs by conventional CGH and array CGH. Conventional CGH revealed that increases of DNA copy number were frequent at 1q (79% of the cases), 8q (37%), 6p (32%), and 10p (32%) and that decreases were frequent at 17p (79%), 16q (58%), 4q (53%), 13q (42%), 10q (37%), 1p (32%), and 8p (32%). In general, genes that showed DCNAs by array CGH were usually located in chromosomal regions with DCNAs detected by conventional CGH analysis. Increases in copy numbers of the LAMC2, TGFB2, and AKT3 genes (located on 1q) and decreases in copy numbers of FGR/SRC2 and CYLD (located on 1p and 16q, respectively) were observed in more than 30% of tumors, including small, well-differentiated carcinomas. These findings suggest that these genes are associated with the development of HCV-HCC. Increases of MOS, MYC, EXT1, and PTK2 (located on 8q) were detected exclusively in moderately and poorly differentiated tumors, suggesting that these alterations contribute to tumor progression. In conclusion, chromosomal and array CGH technologies allow identification of genes involved in the development and progression of HCV-HCC.  相似文献   
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55.
Background Although there have been reports dealing with ventricular diverticulum (VD) analyzed by cisternography and computed tomography (CT), those focusing on magnetic resonance imaging (MRI) or neuroendoscopic findings are rare. Case report We present a case of noncommunicating hydrocephalus caused by aqueductal stenosis with cystic lesion located in supracerebellar region. Third ventriculostomy was performed on this case. The conventional CT and MRI were compatible with usual VD, but neuroendoscopic examination suggested otherwise. The endoscopic view inside of the cystic lesion demonstrated passing veins and no membrane. We diagnosed this cystic lesion as a unique subtype of advanced VD mimicking spontaneous ventriculostomy. Endoscopic observation of the cyst was very useful for accurate diagnosis and safe treatment.  相似文献   
56.
Preface     
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58.
Skull metastasis of thyroid carcinoma is rare. The majority of skull metastases of thyroid carcinoma are of the follicular subtype, rather than thyroid papillary carcinoma. In this report, a 55-year-old woman with skull metastasis from thyroid papillary carcinoma is presented. The metastatic lesion of the skull was hypervascular and osteolytic, and the bleeding was profuse during resection. There have been only four reports of skull metastasis from thyroid papillary carcinoma. The mean period from the initial diagnosis of thyroid carcinoma until the detection of skull metastasis is 23.3 years, whereas in this patient, it was about 2 years. Therefore, in the clinical course of thyroid papillary carcinoma, skull metastasis should be considered, and the patient should be meticulously followed up.  相似文献   
59.
In order to estimate the diagnostic validity of chemical fecal occult blood tests, i.e. orthotolidine (Shionogi A) and guajac (Shionogi B) slides for detecting cancers of the esophagus, stomach and colorectum, the authors followed up all the examinees (n=3,449) of comprehensive medical check-ups at the Center for Adult Diseases, Osaka, by means of record linkage to the Osaka Cancer Registry's files. Then, diagnostic validity was calculated based on the results of two years' follow-up. Sensitivity for the respective cancers was 20.0%, 11.8% and 62.5% for Shionogi A, and 20.0%, 5.9% and 43.8% for Shionogi B slides. Likelihood ratio for the respective cancers was 1.4, 0.8 and 4.5 for Shionogi A, and 3.3, 1.0 and 7.5 for Shionogi B. Specificity was analogous among the three cancer sites, being 86% for Shionogi A and 94% for Shionogi B. These results suggest that the diagnostic validity of chemical occult blood tests for detecting cancers of the esophagus and the stomach is very poor, and therefore imply that close examinations of these sites for screening positives is unnecessary in mass screenings for colorectal cancer.  相似文献   
60.
The purpose of this study was to investigate the intestinal hemodynamics and gut glutamine metabolism during endotoxemia, and their correlation with altered intestinal absorptive capacity and permeability. Seventeen Sprague-Dawley rats were used in the study. The endotoxin group (ENDO) recieved endotoxin (10 mg/kg intraperitoneally,n=9), while the control group (CONT,n=8) received saline injection. Twelve hours later, D-xylose (0.5 g/kg) and fluorescein isothiocyanate-dextran (FITC-dextran, 750 mg/kg) were given by oral gavage. One hour later abdominal aortic (AA) blood flow, superior mesenteric venous (SMV) flow, mean arterial pressure (MAP), central venous pressure (CVP), and SMV pressure (SMVP) were also measured. The MAP, AA, and SMV blood flow decreased (P<0.05), while the CVP and SMVP increased (P<0.05) in the ENDO group as compared with the CONT group. The ENDO group showed significant decreases for both intestinal glutaminase activity and net intestinal glutamine uptake (P<0.05). The D-xylose concentration in SMV decreased significantly (P<0.05) in the ENDO group as compared with the CONT group. However, the plasma FITC-dextran concentration showed no significant difference between the groups. Endotoxin produced a hypodynamic effect in rats 12h after intraperitoneal administration in association with both a decreased intestinal glutamine metabolism and an absorptive capacity.  相似文献   
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