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1.
New techniques are proposed for differentiating each type of gastric epithelial cell in the same tissue section. The techniques combine the following stains: paradoxical concanavalin A staining (PCS) to identify mucous neck cells, periodic acid Schiff-concanavalin A staining to distinguish mucous neck cells from surface mucous cells, and a modified Bowie's stain to demonstrate zymogen granules of chief cells. Feulgen hydrolysis preceding the Bowie stain was found to remove most of the nonspecific coloration encountered with the original Bowie method. The results obtained by the new sequences were as follows: Feulgen hydrolysis-PCS-Bowie staining: mucous neck cells stained brown and chief cell zymogen granules deep blue. The other mucin-secreting cells remained unstained; Feulgen hydrolysis-PAS-concanavalin A-Bowie staining: mucous neck cells stained brown, zymogen granules stained deep blue to purplish blue and surface mucous cells stained purplish red.  相似文献   
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Summary This study was undertaken, employing the immunoenzyme method, to confirm the presence of retinol-binding protein in human pancreatic islets, and to compare its distribution with that of prealbumin, insulin, glucagon, somatostatin and pancreatic polypeptide. It was found that most islet cells contained retinol-binding protein, although centrally located cells showed stronger reactivity than those in the peripheral region. The distribution of each of the five polypeptides differed from that of retinolbinding protein, indicating that these peptides did not cross-react with anti-retinol-binding protein antibody. Islet cells which contained prealbumin, on the other hand, were mostly classified as A cells. Further studies are necessary to confirm whether the islet cells produce retinol-binding protein or only store it.  相似文献   
3.
A new technique to eliminate O-glycosidically linked glycoprotein (mucin-type glycoprotein) selectively has been developed. Composite paraffin sections were collodionized before and after alkaline treatment with 0.5 M NaOH in 70% ethanol; the effect of this procedure on mucosubstances was examined using the periodic acid-Schiff reaction. Exposure to alkaline hydrolysis for 72 to 144 hours at 4 C led to a complete loss of periodic acid-Schiff reactivity of epithelial mucins in rat sublingual gland, stomach and small intestine, but that of fuzzy coat, thyroid colloid, collagen fibers and tracheal cartilage was well preserved. These results agreed fairly well with biochemical findings. The present study also revealed that materials prepared by freeze-substitution provided the most satisfactory results.  相似文献   
4.
Epidemiological typing, based on restriction fragment length polymorphism (RFLP) by pulsed-field gel electrophoresis (PFGE), was attempted for the 38 clinical isolates of Moraxella catarrhalis obtained at Shinshu University Hospital during the years 1987 and 1993. Digestion with SmaI or NotI generated well separable, 12 to 5 genomic DNA fragments ranging from 1,000 kb to 30 kb and the strains could be classified into 14 or 13 types, respectively. The electrophoretic profile differed with the strain in most of them and was hence useful to distinguish the each strain. Investigation for their RFLP have, however, suggested that majority of them, including the type strain ATCC25238, may have derived from a common ancestor.  相似文献   
5.
The matrix of some mitochondria in gastric parietal cells of rat and guinea pig evidenced affinity for the high iron diamine method which localizes sulfated complex carbohydrates selectively by light and electron microscopy. Such staining has not been observed elsewhere in the stomach. The high iron diamine reactive mitochondria about equaled in number those which were unreactive, and the two groups were indistinguishable morphologically. The distinction was not apparent either when mitochondria were stained by other cytochemical procedures including dialyzed iron for acidic complex carbohydrates, 3-3' diaminobenzidine-H2O2 at pH 6.0 for cytochrome oxidase, and Kominick's pyroantimonate osmium tetroxide for antimonate precipitable cations. The dialyzed iron method stained acid glycoconjugates in the outer intermembrane space in parietal cell mitochondria. These mitochondria stained more strongly with dialyzed iron than have any others examined heretofore with this method and comprised the only reactive mitochondria in the stomach. Parietal cell mitochondria also stained strongly for cytochrome oxidase but those of other gastric cells failed to evidence this reactivity.  相似文献   
6.
A new apolipoprotein complex designated as the apo(AII-E2-AII) complex was identified in the lipoprotein fractions of human plasma with apoE phenotypes containing apoE2 (E4/E2, E3/E2, and E2/E2). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by an immunoblotting assay using anti-apoE or anti-apoAII antibodies, established that the apo(AII-E2-AII) complex, with a molecular weight of 58,000, was identical to the complex consisting of apoE and apoAII, and that it also dissociated following reduction with beta-mercaptoethanol. This new complex was also demonstrated to be distinct from the apo(E-AII) complex and apoE monomer by isoelectric focusing, in the samples that were not treated with beta-mercaptoethanol. In apoE phenotype E3/E2, the apo(AII-E2-AII) complex was primarily included in the high-density lipoprotein (HDL, 1.063 < d < 1.21 g/ml) fraction, but was also observed in a small quantity in the very-low-density lipoprotein (VLDL, d < 1.006 g/ml) fraction. For further characterization, the apo(AII-E2-AII) complex was isolated by preparative SDS-PAGE, and no contamination of apo(E-AII) complex and apoE monomer was detected by immunoblotting assay using an anti-apoE antibody. It was confirmed by an enzyme-linked immunosorbent assay (ELISA) system that a molecular ratio between apoAII monomer and apoE in the isolated apo(AII-E2-AII) complex was approx. 2, when the apo(E-AII) complex was used as a standard with the ratio of 1:1. It indicates that the apo(AII-E2-AII) complex is formed from two molecules of apoAII monomer and one molecule of apoE.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.  相似文献   
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Natural killer cell responses play a crucial role in virus clearance by the innate immune system. Although the killer immunoglobulin-like receptor (KIR) in combination with its cognate human leukocyte antigen (HLA) ligand, especially KIR2DL3-HLA-C1, is associated with both treatment-induced and spontaneous clearance of hepatitis C virus (HCV) infection in Caucasians, these innate immunity genes have not been fully clarified in Japanese patients. We therefore investigated 16 KIR genotypes along with HLA-B and -C ligands and a genetic variant of interleukin (IL) 28B (rs8099917) in 115 chronic hepatitis C genotype 1 patients who underwent pegylated-interferon-α2b (PEG-IFN) and ribavirin therapy. HLA-Bw4 was significantly associated with a sustained virological response (SVR) to treatment (P = 0.017; odds ratio [OR] = 2.50, ), as was the centromeric A/A haplotype of KIR (P = 0.015; OR 3.37). In contrast, SVR rates were significantly decreased in patients with KIR2DL2 or KIR2DS2 (P = 0.015; OR = 0.30, and P = 0.025; OR = 0.32, respectively). Multivariate logistic regression analysis subsequently identified the IL28B TT genotype (P = 0.00009; OR = 6.87, 95% confidence interval [CI] = 2.62 - 18.01), KIR2DL2/HLA-C1 (P = 0.014; OR = 0.24, 95% CI = 0.08 - 0.75), KIR3DL1/HLA-Bw4 (P = 0.008, OR = 3.32, 95% CI = 1.37 - 8.05), and white blood cell count at baseline (P = 0.009; OR = 3.32, 95% CI = 1.35 - 8.16) as independent predictive factors of an SVR. We observed a significant association between the combination of IL28B TT genotype and KIR3DL1-HLA-Bw4 in responders (P = 0.0019), whereas IL28B TT along with KIR2DL2-HLA-C1 was related to a non-response (P = 0.0067). In conclusion, combinations of KIR3DL1/HLA-Bw4, KIR2DL2/HLA-C1, and a genetic variant of the IL28B gene are predictive of the response to PEG-IFN and ribavirin therapy in Japanese patients infected with genotype 1b HCV.  相似文献   
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