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101.
Consumption of wild boar linked to cases of hepatitis E   总被引:9,自引:0,他引:9  
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Verapamil is widely used for the termination of paroxysmal supraventricular tachycardia (PSVT) with little proarrhythmic effect. We describe two cases of PSVT that changed to non-sustained polymorphic ventricular tachycardia after administration of verapamil. Electrophysiological study revealed atrioventricular nodal reentrant tachycardia in the first case, and atrioventricular reentrant tachycardia due to a concealed left lateral accessory pathway in the second case. Catecholamine-induced automaticity was one of the possible mechanisms of VT in the first case, but the mechanism is unknown in the second case.  相似文献   
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Background:  Autoreactive T cells that proliferate in response to autoantigens are found in both autoimmune diseases and controls but have important qualitative differences in relative activation states, costimulation signal requirements and pathogenetic significance.
Methods:  To understand the differences between autoreactive T cells in PBC versus controls, we have developed autoreactive T-cell clones (TCC) from patients with PBC and healthy controls, and have used a peptide corresponding to the CD4 major autoantigen (Ag) to define the relative proliferative response. Peripheral blood mononuclear cells (PBMC) from PBC respond to the Ag in a costimulation-independent manner, but PBMC from controls respond to the Ag in a costimulation-dependent manner. Next, we established nine autoreactive TCC from patients with PBC and eight from healthy controls.
Results:  Among 17 TCC, eight were the costimulation-dependent type and nine were independent. In addition, costimulation-dependent autoreactive TCC became anergic after stimulation in the presence of APC that did not provide costimulatory signals. Finally, we observed that anergic TCC exhibit regulatory functions.
Conclusions:  In the case of regulatory dendritic cells, we could not induce TCC anergy. On the other hand, when using peptide analog in a costimulation-deficient manner, we could induce TCC anergy, even though these TCC were costimulation independent.  相似文献   
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ABSTRACT— To clarify the relationship between angiogenesis and hepatocarcinogenesis on progression of hepatocellular carcinoma (HCC), we quantitatively evaluated angiogenesis by CD34 immunohistochemistry in liver cirrhosis (LC), adenomatous hyperplasia (AH), and HCC, and proliferative activity estimated by Ki-67 immunohistochemistry. Angiogenesis was evaluated by CD34 immunohistochemistry using monoclonal antibody HPCA-2, and tumor proliferative activity was evaluated using monoclonal antibody MIB-1. We used an image analysis system to assess the microvessel density as the area percentage of the endothelial area. Angiogenesis was generally observed in HCC and there was no significant difference among all clinical stages and histological grades of HCC. On the other hand, the staining of CD34 was partly observed in sinusoids of AH, although no positive staining was seen in any sinusoids of LC. The proliferative activity was significantly correlated with the clinical stage and histological grade of HCC. Our results indicate that the quantitation of angiogenesis does not provide significant prognostic information in HCC, but that it may have diagnostic value in distinguishing HCC from non-HCC. Meanwhile, AH, which is not morphologically diagnosed as cancer, shows positive staining for CD34, suggesting that some portion of AH contains cancerous characteristics.  相似文献   
106.
BACKGROUND/AIMS: The presence of antibodies to the 210-kDa glycoprotein of the nuclear pore complex (gp210) is highly indicative of primary biliary cirrhosis (PBC). However, the significance of anti-gp210 antibody titers for monitoring PBC remains unresolved. METHODS: We used an ELISA with a gp210 C-terminal peptide as an antigen to assess serum antibody titers in 71 patients with PBC. RESULTS: Patients were classified into three groups: Group A in whom anti-gp210 titers were sustained at a high level, Group B in whom anti-gp210 status changed from positive to negative under ursodeoxycholic acid (UDCA) therapy, Group C in whom anti-gp210 antibodies were negative at the time of diagnosis. The rate of progression to end-stage hepatic failure was significantly higher in group A (60%) as compared to groups B (0%) and C (4.2%). The sustained antibody response to gp210 was closely associated with the severity of interface hepatitis. The significance of anti-gp210 antibody was confirmed by National Hospital Organization Study Group for Liver Disease in Japan. CONCLUSIONS: The serial quantitation of serum anti-gp210-C-terminal peptide antibodies is useful for monitoring the effect of UDCA and for the early identification of patients at high risk for end-stage hepatic failure.  相似文献   
107.

The effects of the water extract of Sinomeni Caulis et Rhizoma (SCR-WE) and its major constituents, sinomenine (SIN) and magnoflorine (MAG), on moderate hemolysis induced by lysophosphatidylcholine (LPC) were investigated in rat erythrocytes and compared with the anti-hemolytic effects of lidocaine (LID) and propranolol (PRO) as reference drugs. LPC caused hemolysis at concentrations above the critical micelle concentration (CMC), and the concentration of LPC producing moderate hemolysis (60 %) was approximately 10 μM. SCR-WE at 1 ng/mL–100 μg/mL significantly inhibited the hemolysis induced by LPC. SIN and MAG attenuated LPC-induced hemolysis in a concentration-dependent manner from very low to high concentrations (1 nM–100 μM and 10 nM–100 μM, respectively). In contrast, the inhibiting effects of LID and PRO on LPC-induced hemolysis were observed at higher concentrations (1–100 μM) but not at lower concentrations (1–100 nM). Neither SIN nor MAG affected micelle formation of LPC, nor, at concentrations of 1 nM–1 μM, did they attenuate the hemolysis induced by osmotic imbalance (hypotonic hemolysis). Similarly, SCR-WE also did not modify micelle formation or hypotonic hemolysis, except at the highest concentration. These results suggest that SIN and MAG potently protect the erythrocyte membrane from LPC-induced damage and contribute to the beneficial action of SCR-WE. The protective effects of SIN and MAG are mediated by some mechanism other than prevention of micelle formation or protection of the erythrocyte membrane against osmotic imbalance.

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Mycotic aneurysm is a rare but life-threatening disease that warrants an integrated therapeutic approach involving surgical intervention and prolonged antibiotic use. However, the causative organisms are often unidentified because antibiotics started empirically render blood and tissue cultures negative. Molecular diagnosis has been reported to be useful in such culture-negative cases. We report a case of a culture-negative mycotic aortic aneurysm due to Haemophilus influenzae, diagnosed by direct 16S rRNA polymerase chain reaction (PCR) and sequencing of the resected aneurysm tissue. PCR for serotype revealed type b, and PCR and sequencing of the ftsI gene revealed alterations in penicillin-binding protein 3, suggesting resistance to ampicillin. Multilocus sequence typing demonstrated that the isolate belonged to sequence type 54.  相似文献   
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