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1.
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
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Background Extended trans septal (ETS) approach for mitral valve surgery often divides the artery to the Sino-Atrial node. The clinical implication of this is contentious. We analyzed our early results with ETS approach. Methods Between June 1998 and September 2003 eleven patients underwent mitral valve surgery by ETS approach. Six were females. Age ranged from 19 years to 67 years (median 40 years). Six underwent mitral valve replacement (MVR). Four underwent aortic and mitral (double) valve replacement (DVR). One had mitral valve repair. Three had additional procedures (tricuspid valve repair=1, Coronary artery bypass=1, Aorto bifemoral graft=1). Cardiopulmonary bypass ranged from 64 minutes to 77 minutes (median 72 minutes) for MVR and 112 minutes to 178 minutes (median 140 minutes) for DVR. Aortic cross clamp times ranged from 39 minutes to 52 minutes (median 47 minutes) for MVR and 74 minutes to 120 minutes (median 95 minutes) for DVR. Results There was no mortality or morbidity attributed to the ETS approach. One early death in emergency DVR was due to heart failure. Three patients needed seqeuntial pacing in the immediate post-operative period. Nine out of ten survivors were back to their preoperative rhythms on hospital discharge (6 sinus rhythm; 3 atrial fibrillation). One patient with preoperative trifascicular block who underwent reoperation to fix a paravalvular mitral leak needed a permanent pacemaker (VVI). The follow-up ranged from 1 month to 64 months (median 6 months) and is 100% complete. There was no late death or new arrhythmia. Conclusions Extended trans septal approach is safe. It gives excellent exposure of the mitral valve. division of the sinus node artery is not deleterious in the short to intermediate term. Presented at the 50th Annual Meeting of IACTS. New Delhi, Feb. 2004.  相似文献   
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Fenfluramine, an amphetamine derivative used in the treatment of obesity, has been evaluated in vivo in the bone marrow cells of Swiss albino mice using two cytogenetic endpoints for assessing its genotoxic and clastogenic potentials. Concentrations of 0.75, 1.5, 3.0, and 5.0 mg/kg b.w. were administered orally for the study of sister chromatid exchange frequencies and chromosome aberrations (CA). SCE frequencies showed a positive dose response; 1.5 mg/kg being the minimum effective concentration. Fen caused a prolongation of cell cycle at all concentrations. Except for the minimum therapeutic dose (0.75 mg), all other doses (1.5, 3.0, and 5.0 mg) showed a significant increase in the percentage of damaged cells over that of the vehicle control. The degree of clastogenicity was directly proportional to the dosage used and inversely related with the duration of treatment. A gradual reduction of the clastogenic potential was observed after 12 and 24 hr of exposure, indicating that the maximum effect occurs at the middle or late synthetic phase of the cell cycle. This study, probably the first detailed screening of the drug for its genotoxicity, shows that Fen is moderately clastogenic and a DNA damaging agent in vivo.  相似文献   
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The activities of the enzymes related to glutathione synthesis, degradation, and functions as well as reactive oxygen scavenging enzymes were analyzed in different brain regions, such as cerebral hemisphere, cerebellum, brainstem, thalamus, and hypothalamus after 1 and 3 mo of streptozotocin-induced diabetes in rats. Parallel studies were also made in age-matched control rats and insulin-treated diabetic rats. The content of glutathione (GSH) and its synthesizing enzyme γ-glutamylcystein synthetase and also superoxide dismutase (SOD) and catalase activities (reactive oxygen scavenging enzymes) were significantly decreased from almost all the brain regions studied. However, glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), γ-glutamyl transpeptidase (γ-GTP), and glutamine synthetase (GS) activities were increased in the diabetic rat brain. Insulin treatment to the diabetic rats resulted in partial to full recovery in these enzymes activities. The present results emphasize the potentially serious alterations of brain free radical scavenger system in uncontrolled Type I diabetes.  相似文献   
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Mosaicism for an FMR1 gene deletion in a fragile X female   总被引:2,自引:0,他引:2  
Most cases of fragile X syndrome result from expansion of CGG repeats in the FMR1 gene; deletions and point mutations of FMR1 are much less common. Mosaicism for an FMR1 full mutation with a deletion or with a normal allele has been reported in fragile X males. Here we report on a fragile X female who is mosaic for an FMR1 full mutation and an intragenic deletion. The patient is a 4-year-old girl with developmental delay, autistic-like behaviors, and significant speech and language abnormalities. Southern blotting demonstrated the presence of a methylated full mutation, a normal allele in methylated and unmethylated forms, and an additional fragment smaller than the normal methylated allele. This result indicates that the patient is mosaic for a full mutation and a deletion, in the presence of a normal allele. By DNA sequence analysis, we mapped the 5' breakpoint 63/65 bp upstream from the CGG repeat region and the 3' breakpoint 86/88 bp downstream of the CGG repeats within the FMR1 gene. The deletion removed 210 bp, including the entire CGG repeat region. The full mutation was inherited from a premutation in the patient's mother. The deletion, which remained methylated at the Eag I and Nru I sites, was probably derived from the full mutation allele. Mosaicism of this type is rare in females with a fragile X mutation but should be kept in mind in the interpretation of Southern blots.  相似文献   
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Steatosis is a frequent pathologic stage in alcoholic liver disease (ALD). Although the mechanisms for increased susceptibility of steatotic liver to injury have been postulated, the ability of these hepatocytes to proliferate and withstand injury is unknown. There are conflicting reports on the status of hepatocyte regeneration following chronic alcohol ingestion. Hence, the objective of this study was to investigate the temporal dynamics between the pattern of liver injury and hepatocyte proliferation during the steatosis stage of ALD. Alcoholic steatosis was induced in male Sprague-Dawley rats by feeding an ethanol (EtOH)-containing Lieber-DeCarli liquid diet for a period of 5 weeks. Microvesicular steatosis was evident in H&E sections by three weeks in the EtOH-treated rats, which further developed into panlobular macrovesicular steatosis by 5 weeks. Plasma transaminase activities indicated progressive increase in liver injury peaking at 3 weeks with significant but mild decrease at 4 and 5 weeks. CYP2E1 protein and activity was significantly increased in EtOH-fed rats as measured by Western blot and pNP hydroxylation assay. PCNA analysis of liver sections indicated that EtOH-treated rats had a significantly higher number of cells in S phase of cell division at weeks 1 (3.20 +/- 0.19), 2 (7.03 +/- 0.92), and 3 (4.23 +/- 1.41) when compared to controls (1.5 +/- 0.22). NF-kappaB DNA binding and Cyclin D1 proteins increased significantly in the EtOH-treated rats corresponding with enhanced hepatic proliferation. These data suggest the transient decline in liver injury during alcoholic steatosis is due to enhanced NF-kappaB-dependent hepatocyte proliferation.  相似文献   
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The cytokine tumor necrosis factor was originally identified as a protein that kills tumor cells. So far, 18 distinct members of this family have been identified. All of them regulate cell survival, proliferation, differentiation, and cell death, also called apoptosis. The apoptosis induced by TNF, and other members of the family, for example, FasL, VEGI, and TRAIL is mediated through death receptors. The apoptotic signals by these cytokines are transduced by eight different death domain- (DD) containing receptors (TNFR1, also called DR1; Fas, also called DR2; DR3, DR4, DR5, DR6, NGFR, and EDAR). The intracellular portion of all these receptors contains a region approximately 80 amino acids long referred to as the death domain. Upon activation by its ligand, the DD recruits various proteins that mediate both death and proliferation of the cells. These proteins in turn recruit other proteins via their DDs or death effector domains. The actual destruction of the cell, however, is accomplished by serial activation of a family of proteases referred to as caspases. Cell death is negatively regulated by a family of proteins that includes decoy receptors, silencer of DD, sentrin, cellular FLICE inhibitory protein, cellular inhibitors of apoptosis, and survivin. This review is an attempt to describe how these negative and positive players of cell death perform a harmonious dance with each other.  相似文献   
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