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981.
The neural precursor cell-specific marker nestin is expressed in fetal and adult pancreas, but its role is not fully understood. Using nestin-enhanced green fluorescent protein (EGFP) transgenic mice and fluorescence activated cell sorter, we characterized nestin-positive cells in adult mice pancreas. EGFP mRNA- and protein-positive cells expressed amylase, a pancreatic exocrine marker. Interestingly, EGFP mRNA-negative and protein-positive cells expressed insulin, glucagon, somatostatin and pancreatic polypeptide, pancreatic endocrine markers. These findings demonstrate that nestin-positive cells comprise a portion of pancreatic exocrine cells and suggest that they can be differentiated into pancreatic endocrine cells.  相似文献   
982.
983.
We performed molecular analysis of complement components (C3, C4, and factor B) in human bile by sodium dodecyl sulfate-polyarylamide gel electrophoresis (SDS-PAGE) and immunoblotting. Complement C3 was detected as a molecule composed of a 115-kDa α-chain linked to a 70-kDa β-chain by disulfide bonds, and C3 levels ranged from 45 to 650μg/ml (n=15). C4 was detected as a triple chain (98-kDa α-chain, 73-kDa β-chain, and 33-kDa γ-chain) molecule linked by disulfide bonds, and C4 levels ranged from 2.5 to 60μg/ml. Factor B, a component of the alternative pathway, was also detected, as an intact form. Factor B levels ranged from 0.3 to 8.0μg/ml. The sizes and subunit structures of complement components in human bile were compatible with those reported in human serum. The results of a hemolytic assay indicated that complement molecules in human bile were functionally active. These molecules may participate in local immune and inflammatory responses in the biliary tract.  相似文献   
984.
A recently developed method to quantitate prothrombin in plasma uses the carinactivase-1 (CA-1) method. The present study was designed to establish the reference value by the CA-1 method in the neonatal period and to explore the effect of gestational age, birth weight, concurrent diseases, and vitamin K administration on the prothrombin levels. We enrolled 78 consecutive neonates. The gestational ages ranged from 28 to 41 weeks, and the birth weight ranged from 850 to 3750 g. Twenty-nine infants had concurrent diseases, and the others (n = 49) were healthy. A 300 microL blood sample was drawn into a plastic syringe containing 60 U freeze-dried buffered heparin. Prothrombin levels did not differ between appropriate-for-date (AFD) and light-for-date (LFD) babies (p = 0.090) or between groups with and without concurrent diseases (p = 0.210). In healthy AFD babies, prothrombin levels correlated with gestational age (r = 0.465, p = 0.003) and birth weight (r = 0.458, p = 0.003). In healthy low-birth-weight infants (n = 14) and those with concurrent diseases (n = 17), the changes after vitamin K administration were not significant. The CA-1 method is of clinical use in monitoring coagulation during the early neonatal period.  相似文献   
985.
986.
Cholangiographic findings of early-stage extrahepatic bile duct carcinoma   总被引:1,自引:0,他引:1  
BACKGROUND: To clarify the cholangiographic findings of early-stage (T1, tumor confined to the mucosal or fibromuscular layer) extrahepatic bile duct carcinoma. METHODS: Cholangiographic images were retrospectively analyzed without other information in 55 patients with extrahepatic bile duct carcinoma who underwent surgical treatment. Tumor stages were T1 (n = 10). T2 (n = 17), and T3 (n = 28). Cholangiographic findings were classified as "diffuse sclerosis," "stenosis," "papillary polypoid filling defect," or "nodular polypoid filling defect". "Papillary polypoid filling defect" was the term used when the width of the base was smaller than the width of the polypoid filling defect. RESULTS: T1 patients showed papillary polypoid filling defects (n = 8) or nodular polypoid filling defects (n = 2) on cholangiography. When cholangiography showed papillary polypoid filling defects, 8 of the 14 resected patients showed T1 stage tumor histologically. CONCLUSIONS: In this study, 57% (8/14) of resected patients with papillary polypoid filling defects showed T1 stage tumor. No T1 stage tumor showed stenosis or diffuse sclerosis.  相似文献   
987.
A 72-year-old man with acute myelocytic leukemia (AML) suffered relapsing massive bleeding from gastric angiodysplasia. He was referred to our hospital in February 2000 because of anemia and thrombocytopenia. He had hypercellular (nucleated cell count 42 x 10(4)/microl) bone marrow with 90% myeloblasts, and AML (FAB: M1) was diagnosed. Remission induction therapy by BHAC/DM regimen failed. While considering subsequent regimens, massive hematemesis from a solitary gastric angiodysplasia developed. In April, after re-remission induction by CAG regimen, hematemesis from the same lesion reccurred. Hemostasis was achieved by topical transendoscopic injection of polidocanol. After achievement of complete remission by CAG therapy, he was treated on an outpatient basis. In July, his AML relapsed and he was treated mainly by transfusion therapy. In September, hematemesis recurred resulting in hemostasis with the same procedure. In the course of endoscopic injections, his mucosal lesion became difficult to observe. Gastric angiodysplasia is occasionally observed in the elderly, but massive bleeding is a rare complication. In this case, topical injection of polidocanol was an effective procedure for the massive bleeding from it even in an elderly patient with the complication of thrombocytopenia due to AML.  相似文献   
988.
The etiopathogenesis of extrahepatic manifestations including vasculitis in the context of HCV infection is still unknown. We report a case with lethal extrahepatic manifestations due to chronic hepatitis C virus (HCV) infection. The patient presented leukocytoclastic vasculitis, sensorimotor neuropathy and membranoproliferative glomerulonephritis with positive rheumatoid factor but lacked cryoglobulin. Hypocomplementaemia and deposition of IgM and C3 in the vascular lesion and glomeruli suggested that immune complex disease played a role in the pathogenesis of extrahepatic manifestations independent of cryoglobulin. Although HCV was successfully eliminated by treatment with interferon alpha, she died of cryptococcal infection.  相似文献   
989.

Background

IgG4 production is regulated by type 2 (IL-4 and IL-13) and regulatory (IL-10) cytokines involved in the pathophysiology of chronic rhinosinusitis (CRS). We sought to determine the pathophysiological characteristics of IgG4-positive cells in sinonasal tissues in CRS, especially eosinophilic CRS (ECRS).

Methods

IgG4-positive cells in uncinate tissues (UT) and nasal polyps (NP) were examined by immunohistochemistry. Associations between the number of IgG4-positive cells and clinicopathological factors were analyzed. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of IgG4-positive cells in tissue that can predict the post-operative course.

Results

IgG4 was mainly expressed in infiltrating plasma and plasmacytoid cells, and the number of IgG4-positive cells was significantly higher in NP, especially those from severe ECRS patients, than in UT. In CRS patients, the number of IgG4-positive cells significantly and positively correlated with blood and tissue eosinophilia, radiological severity, and serum level of total IgE. The number of infiltrating IgG4-positive cells was significantly higher in patients with a poor post-operative course (sustained sinus shadow 6 months after surgery) than in those with a good one. The number of IgG4-positive cells in NP could discriminate patients with a good or a poor post-operative course (area under the curve: 0.769). Also, 73.3% sensitivity and 82.5% specificity were achieved when the cut-off value was set at 17 cells/high-power field.

Conclusions

Our results suggest that the local expression of IgG4 on cells may be used as a biomarker that reflects the pathophysiology of CRS, including the post-operative course.  相似文献   
990.
The present study was conducted to examine the effect of eicosapentaenoic acid supplements on pulse wave velocity (PWV) in patients with dyslipidemia as a prospective open-labeled study. Eicosapentaenoic acid supplements (1,800 mg/day) were prescribed to 40 patients, and diet therapy in consultation with a nutritionist was conducted in 44 patients as a control group. These interventions were continued for 12 months, and PWV and blood examinations were performed at the start and end of these interventions. PWV increased in the control group but not in the eicosapentaenoic acid group. After adjustment for age, gender, the initial PWV, and the changes in mean blood pressure during the study period, a general linear model univariate analysis post hoc comparison demonstrated that the change in PWV during the period of study was significantly larger in the control group (42 +/- 20 cm/s) than in the eicosapentaenoic acid group (-9 +/- 19 cm/s) (p<0.05). Thus, this preliminary study suggested that eicosapentaenoic acid supplements attenuate age-related increases in arterial stiffness in patients with dyslipidemia. A further study with a larger number of subjects is proposed to confirm this beneficial effect of eicosapentaenoic acid supplements on arterial stiffness.  相似文献   
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