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1.
The pharmacokinetics of 1-(tetrahydro-2-furanyl)-5-fluorouracil (FT) and its conversion into 5-fluorouracil (FUra) in liver tissue were studied in ten patients with hepatocellular carcinoma (HCC). The plasma concentration of FT after its intravenous injection (dosage: 800 mg) was computerfitted to a bi-exponential function (C = Ae-alpha t + Be-beta t), indicating a two-compartment disposition. The pharmacokinetic parameters did not significantly differ between the five patients with, and the five without cirrhosis of the liver. The plasma concentrations of FUra likewise showed no significant difference between the two groups. The rates of FT degradation in the liver tissue homogenate were similar for four of the patients with cirrhosis (0.10 +/- 0.05 mumol/g liver protein/30 min) and four of those without it (0.13 +/- 0.05). The rates of cytochrome P-450-dependent FUra formation in the microsomal fraction of liver tissue from two patients (1.1 and 1.3 nmol/mg microsomal protein/30 min) were dramatically reduced to less than half of those of two control subjects (2.4 and 2.7). The estimated rates of FUra formation in the soluble fraction (105,000 X g supernatant fraction) from the two patients (0.1 and 0.13 nmol/mg protein/30 min) were almost identical to those from the controls (0.12 and 0.14), suggesting that the rate in the soluble fraction from HCC patients may not be as strongly affected as the rate in the microsomal fraction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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In this review article, we demonstrate the mucin expression profile in normal tissue, invasive ductal carcinoma (IDC), two subtypes of intraductal papillary–mucinous neoplasm (IPMN dark cell type and IPMN clear cell type), pancreatic intraepithelial neoplasia (PanIN), and mucinous cystic neoplasm (MCN) of the pancreas. In MUC1, there are various glycoforms, such as poorly glycosylated MUC1, sialylated MUC1, and fully glycosylated MUC1. IDCs showed high expression of all the glycoforms of MUC1. IPMNs dark cell type showed no expression or low expression of all the glycoforms of MUC1. IPMNs clear cell type showed low expression of poorly glycosylated MUC1, but expression of sialylated MUC1 and fully glycosylated MUC1. Expression of MUC2 was negative in IDCs, high in IPMNs dark cell type and low in IPMNs clear cell type. MUC5AC was highly expressed in IDCs, IPMNs dark cell type, and IPMNs clear cell type. MUC6 expression was higher in IPMNs clear cell type than in IDCs and IPMNs dark cell type. Our recent study demonstrated that high expression of MUC4 in IDCs is correlated with a poor outcome for patients. In PanINs, expression of both MUC5AC and MUC6 are an early event, whereas up-regulation of MUC1 is a late event. MCNs do not look as if they will show a specific mucin expression profile according to the literature review.  相似文献   
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ABSTRACT: Human leukocyte antigen (HLA) genes are candidates for susceptibility genes in insulin-dependent diabetes mellitus (IDDM). Recently, the association of DR and DQ with IDDM has been reported, but the role of HLA-DP genes remains uncertain. To address the question, we analyzed the DPB1 gene of 20 Japanese IDDM patients and 30 control subjects using a combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis (PCR-RFLP method). DPB1*0501 was the most frequent allele both in Japanese patients and control subjects. There was no appreciable association between IDDM and the DPB1 allele in Japanese. The absence of association between IDDM and DP, in spite of the known association between this disease and both DR and DQ, suggests that the HLA locus (loci) telomeric to DP encodes susceptibility to IDDM.  相似文献   
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Lipoprotein metabolism was analyzed in a patient with marked hyper-HDL-cholesterolemia. A 50 year old male with no symptom of ischemic heart disease or xanthoma had a serum cholesterol level between 293 and 410 mg/dl, and a markedly elevated, HDL-cholesterol level (160-190 mg/dl). The cholesterol content of ultracentrifugally separated HDL2 was exclusively increased, while it was normal in the HDL3 fraction. Analytical ultracentrifugation and HPLC revealed that HDL particles became remarkably larger than the control and, on the contrary, LDL particles became smaller. LPL and LCAT activities were higher in this case, but H-TGL activity was normal. Agarose gel electrophoresis of lipoproteins showed an abnormal broad band which was located between alpha and pre beta band. Serum levels of apolipoprotein A-I, A-II, C-II, C-III and E were higher, while apolipoprotein B level was slightly lower than the control. Cholesteryl ester transfer protein (CETP) activity was demonstrated to be completely deficient in this case, as determined in 10 microliters serum using [3H] CE-labeled HDL3 as donor and VLDL + LDL fraction as acceptor. Since CETP was considered to catalyze the cholesteryl ester transport from HDL to VLDL and LDL, the deficiency of this activity might be the cause of the marked hyper-HDL-cholesterolemia in this patient.  相似文献   
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Using the surgically extirpated specimens from 9 patients with colorectal carcinoma, fucosyltransferase activities in the carcinoma tissue and the normal mucosa were measured and were compared with the hlstochemical findings of glycoconjugates which were shown by staining with lectins reacting with blood group antigens and related substances. The fucosyltransferase activities of the carcinoma tissue were well correlated with the overall findings of lectin stainings after neuraminidase treatment. The more intense the carcinoma tissue was stained, the higher the fucosyltransferase activity was shown. However, there were marked differences in the fucosyltransferase activities by the portions measured, depending upon the relative amount of carcinoma tissue and Interstitial tissue; in the invasive portion with less carcinoma tissue, the activity was generally low in comparison with that in the surface area where carcinoma tissue was rather abundant. Thus, the morphological and lectin hlstochemical finding are of paramount importance for the eveluation of glycosyltransferase activity in human colorectal carcinoma.  相似文献   
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Tubuloreticular inclusions (TRI) and paired cisternae (PC) were induced in lymphocytes of normal individuals after incubation with Staphylococcus aureus Cowan 1. TRI were initially detected in lymphoid cells on day 2 (48-h culture). The frequency of TRI-positive cell sections on day 5 increased about twofold over those on days 2-4. On day 7, TRI were predominantly seen in lymphoplasmacytoid cells or plasmacytoid cells, with an incidence of up to 18% of sections. The regions in these cells were most extensive and anastomosed with the cisternae of adjacent well-developed rough endoplasmic reticulum (RER). TRI formation appears not to be essential for mitogen-induced B-cell differentiation to plasmacytoid cells, because pokeweed mitogen (PWM) failed to induce TRI. The diverse expressions of TRI induction between these two mitogens may be due to a difference in B-cell activation mechanisms. Paired cisternae were observed in a great majority of mitotic cells at various stages. These were encountered most frequently on day 4. PC were also seen in the PWM-stimulated culture. Our observations suggest that PC formation may be related to new formation of RER as well as to reconstruction of the nuclear envelope.  相似文献   
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A new ex vivo method for assaying adhesion of cancer cells to the greater omentum has been developed using mouse greater omentum and [3H]labelled human gastric and mouse colorectal cancer cells. Since the adhesion rates were found to increase up to 18 h and labelled cells seemed to be stable during the period, the present method could be useful for investigating adhesion of cancer cells to the greater omentum, which must occur at the first step of the peritoneal dissemination. The adhesion of cancer cells to the greater omentum was inhibited by a series of chemically synthesized oligosaccharides and Galβ1,3[3OMeGalβ1,4GlcNAcβ1,6]αBn was found to be the best inhibitor. The anti-tumor effect of this novel tetrasaccharide in vivo was shown in preliminary experiments using Balb/c mice and colon26 cells.  相似文献   
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