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1.
A case of small fibrolamellar hepatocellular carcinoma (HCC) coexistent with a HCC of common type is herein reported. A 56-year-old man was diagnosed as having multi-nodular type HCC with liver cirrhosis. The serum alpha-fetoprotein (AFP) level was slightly increased. The patient underwent a partial caudate lobectomy and lateral segmentectomy. Histologically, both resected tumors were small HCCs measuring less than 2 cm in diameter. One was a fibrolamellar type located in the caudate lobe, while the other was the common type in the lateral segment of the liver. Positive immunohistochemical staining for AFP was observed in the tumor cells of the HCC of common type but was not observed in the fibrolamellar HCC. We also reviewed previously reported cases of fibrolamellar HCC in Japan, and discussed the clinicopathologic implications of this disease.  相似文献   
2.
To elucidate the mechanism that produces enormous molecular diversity in troponin T (TnT) of fast skeletal muscle, we determined the 5-half genomic sequence of the chicken fast muscle TnT gene. The sequence of ca. 16 kb included seven exons (exons 1, 2, 3, 4, w, 5, and 6), which have been reported previously and presumed by sequencing TnT cDNAs. Additionally we found six 15 nt and one 18 nt sequences in the region between exons 5 and 6 (i.e. the exon x region). They were encompassed by consensus splice donor and acceptor sites and preceded by putative branch sites, and designated herein as exons xa to xg. Our result shows that the sequence derived from exons x1, x2, and x3, the exons presumed previously by cDNA sequencing, is actually encoded by the seven exons xa to xg, establishing the precise gene structure in the exon x region. Based on our data, together with that on the 3-half genomic sequence of the quail fast muscle TnT gene, we conclude that the avian fast skeletal muscle TnT gene includes 27 exons, 16 of which are alternatively spliced.  相似文献   
3.
Nonalcoholic fatty liver disease (NAFLD) is one of the most frequent causes of abnormal liver dysfunction, and its prevalence has markedly increased; however, the mechanisms involved in the pathogenesis of NAFLD have not been thoroughly investigated in humans. In this study, we evaluated the expression of fatty acid metabolism-related genes in NAFLD. Real-time RT-PCR was performed using liver biopsy samples from 12 NAFLD patients. The target genes studied were: acetyl-CoA carboxylase (ACC) 1, ACC2, and fatty acid synthase (FAS) for the evaluation of de novo fatty acid synthesis; carnitine palmitoyltransferase 1a (CPT1a), long-chain acyl-CoA dehydrogenase (LCAD), and long-chain L-3-hydroxyacyl-coenzyme A dehydrogenase alpha (HADHalpha) for beta-oxidation in the mitochondria; peroxisome proliferator-activated receptor- (PPAR-) alpha and cytochrome P450 2E1 (CYP2E1) for oxidation in peroxisomes and microsomes (endoplasmic reticulum) respectively; and diacylglycerol O-acyltransferase 1 (DGAT1), PPAR-gamma, and hormone sensitive lipase (HSL) for triglyceride synthesis and catalysis. In NAFLD, expression of ACC1 and ACC2, but not FAS was increased, indicating that de novo fatty acid synthesis is enhanced in NAFLD. In contrast, expression of CTP1a, a rate-limiting enzyme, was remarkably decreased, indicating that beta-oxidation in the mitochondria was decreased, although the expression of LCAD and HADHalpha was increased. Expression of PPAR-alpha was increased, whereas that of CYP2E1 was reduced. The expression of DGAT1, PPAR-gamma, and HSL was enhanced. These data suggest that in NAFLD, increased de novo synthesis and decreased beta-oxidation in the mitochondria lead to accumulation of fatty acids in hepatocytes, although the extent of oxidation in peroxisomes and microsomes remains unclear.  相似文献   
4.
A 68-year-old man who had been followed at 1-year intervals for a left giant renal cyst was referred to our hospital for left flank pain and fever elevation. Abdominal computed tomographic scan revealed a giant cystic lesion of the left kidney suspected to be communicating with the urinary tract. Percutaneous puncture of this lesion was performed and the fluid was drained. The fluid was yellowish and cloudy, and E. coli was detected by its culture. Injection of contrast medium showed communication between the cyst and the urinary tract. The patient underwent drainage for a ruptured renal cyst. Rupture of a renal cyst is uncommon, and this is the 16th case reported in Japan.  相似文献   
5.
OBJECTIVE: The purpose of this study was to evaluate the prognostic and clinical significance of newly acquired complete right bundle branch block (CRBBB) in airline pilots. PATIENTS: This study included pilots with acquired CRBBB, identified from a group of over 2,700 Japan Airline pilots. When the pilots applied for employment, a past medical history, physical examination, electrocardiogram, and chest radiograph were obtained. The pilots with ECG abnormality including CRBBB were not included in the study because of hiring requirements. RESULTS: Thirty-six pilots with CRBBB were identified between 1983 and 2002. All pilots with CRBBB were evaluated for the presence of ischemic heart disease by treadmill exercise testing, echocardiogram and exercise thallium scintigraphy. Twelve individuals underwent coronary angiography. The mean age of pilots was 44.4 +/- 5.8 years. The mean observation period was 10.9 +/- 5.7 years. For each of the 36 study subjects, Holter electrocardiogram and echocardiogram were obtained every 6 months after the CRBBB was detected. Exercise stress testing was performed every year. Exercise thallium scintigraphy was performed every 2 years to detect ischemic heart disease. During the observation period, two pilots stopped flying temporarily because of frequent ventricular premature beats and one pilot stopped flying permanentaly because of atrial fibrillation. During the follow-up period, no cardiovascular events were observed in pilots with CRBBB who had no underlying ischemic heart disease. CONCLUSION: Acquired CRBBB does not confer a poor prognosis, particularly in young men working as a pilot if there is no evidence of ischemia on exercise stress testing, echocardiography and exercise thallium scintigraphy.  相似文献   
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Purpose

To compare new and conventional versions of model-based iterative reconstruction (MBIR) in reduced-dose computed tomography (CT) in terms of diagnostic performance for hepatic steatosis.

Materials and methods

Images were reconstructed from standard-dose and aggressively reduced-dose (the dose-length product was reduced by 91 %) unenhanced abdominopelvic CT scans of 86 patients using filtered back projection (SD-FBP) and new and conventional versions of MBIR (RD-MBIRn and RD-MBIRc), respectively. The mean CT attenuation of the liver (CT[L]) and the spleen as well as the ratio of these parameters (CT[L/S]) were calculated. CT[L] <48 Hounsfield units (HU) and CT[L/S] <1.1 were applied to SD-FBP (used as the reference standard; the number of positive patients was 12 and 14, respectively), RD-MBIRn, and RD-MBIRc.

Results

CT[L]s in SD-FBP/RD-MBIRn/RD-MBIRc were 56.9/55.9/52.8 HU. The difference in CT[L] between RD-MBIRn and SD-FBP was within ±5.0 HU in most cases. The sensitivity/specificity/accuracy of CT[L] <48 HU in RD-MBIRn and RD-MBIRc were 1.00/0.97/0.98 and 1.00/0.92/0.93, respectively, showing that RD-MBIRn permits significant improvements in specificity and accuracy (P < 0.05, McNemar test). For CT[L/S] <1.1, these values were 0.79/0.97/0.94 and 0.79/0.97/0.94 in RD-MBIRn and RD-MBIRc, respectively.

Conclusion

When CT[L] <48 HU was applied, RD-MBIRn presented a significantly improved hepatic steatosis diagnostic performance compared with RD-MBIRc; indeed, it was almost equivalent to that afforded by SD-FBP.
  相似文献   
9.
A 25-year-old woman was referred to our hospital with persistent upper abdominal pain. Preoperative imaging studies revealed a hilar bile duct stricture with portal venous encasement, and the patient underwent curative resection involving extended left hepatectomy and segmental portal vein resection. The pathological findings demonstrated a well-differentiated tubular adenocarcinoma of the bile duct with regional lymph node metastasis (stage IIIB according to the UICC TNM classification), as well as the overexpression of p53 proteins and the K-ras gene mutation in tumor cells. The patient has shown no evidence of recurrence in the 10 months since the operation. Although there are several reports of relatively young adults with cholangiocarcinoma, the majority of such patients demonstrate either an anomalous arrangement of the pancreaticobiliary duct system or primary sclerosing cholangitis. The absence of any morphological abnormalities in this patient’s biliary system implicates de novo carcinogenesis as the most likely cause of the cholangiocarcinoma.  相似文献   
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