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Adrenergic signalling between rat taste receptor cells   总被引:2,自引:0,他引:2  
In taste buds, synaptic transmission is traditionally thought to occur from taste receptor cells to the afferent nerve. This communication reports the novel observation that taste receptor cells respond to adrenergic stimulation. Noradrenaline application inhibited outward potassium currents in a dose-dependent manner. This inhibition was mimicked by the β agonist isoproterenol and blocked by the β antagonist propranolol. The α agonists clonidine and phenylephrine both inhibited the potassium currents and elevated intracellular calcium levels. Inwardly rectifying potassium currents were unaffected by adrenergic stimulation. Experiments using the RT-PCR technique demonstrate that lingual epithelium expresses multiple α (α1a, α1b, α1c, α1d, α2a, α2b, α2c) and β (β1, β2) subtypes of adrenergic receptors, and immunocytochemistry localized noradrenaline to a subset of taste receptor cells. Collectively, these data imply strongly that adrenergic transmission within the taste bud may play a paracrine role in taste physiology.  相似文献   
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T cell immune response c-DNA (TIRC7) is up-regulated during the early stages of T-cell activation in response to alloantigens. In this study, we analyzed the effects of newly developed monoclonal antibodies (mAb) against TIRC7 in acute cardiac allograft rejection. Fully vascularized heterotopic allogeneic heart transplantation was performed in mice across a full-mismatch barrier (C57Bl/10 into CBA). Recipients received seven injections (day 0-7) of a novel anti-TIRC7 mAb or remained untreated. Graft survival, histology and ex vivo lymphocyte functions were tested. Targeting of TIRC7 with an anti-TIRC7 mAb diminishes lymphocyte infiltration into grafts resulting in delay of morphological graft damage and prolongation of allograft survival. The lymphocytes from anti-TIRC7 mAb-treated animals exhibit hypo-responsiveness without evidence of lymphocyte depletion against the donor allo-antigens. Proliferation and expression of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) were down-regulated while interleukin-4 (IL-4) and IL-10 expression were spared. Moreover, anti-TIRC7 mAb enhanced up-regulation of CTLA-4 expression but suppressed up-regulation of CD25 on stimulated lymphocytes in vitro and in vivo. Ligation of TIRC7 has important effects on the regulation of co-stimulatory signaling pathways associated with suppressing of T-cell activation. Targeting of TIRC7 may therefore provide a novel therapeutic approach for modulating T cell immune responses during organ transplantation.  相似文献   
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Methods: Second primary cancers constitute approximately 9–10% of malignancies diagnosed in the United States. We aimed to show the risk and incidance of second primary tumor occuring associated to urologic tumors and show the distrubution of tumors in Tracia region. We retrospectively examined the patients' files with the diagnosis of malignant disease between the years 1985–2000. Hazard function analysis was performed to estimate the relative risk of secondary malignancy occuring. Age, sex and tumor number were examined to find out if they affect on mortality rate. Results: A total number of 25 MPMNs were diagnosed. In 52 percent of the cases the second primary neoplasm developed within six months. The relative risk of development of a second neoplasm is found as increasing 1.111 times per month. The incidence of secondary malignancy occuring in the patients with one tumor was found as 6.31%. Age (p < 0.001) and tumor number (p < 0.001) are found as statistically effective predictor on mortality rate where the sex is not. Conclusions: In the patients with a primary tumor not only the metastasis must be investigated but also second primary tumors should be taken in to consideration. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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A 42-year-old man with ataxic tetraparesis is reported. Computerized tomography showed bilateral and symmetrical lacunar infarcts at the junctions of the posterior limb of the internal capsule and the corona radiata. Previously this clinical syndrome had been reported only with a lesion in the pons.  相似文献   
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Objective: To investigate whether pentoxifylline could play a role in attenuation of the hazardous effects of ischemia/reperfusion on corporeal tissue in a rat model of veno-occlusive priapism (VOP). Materials and methods: Placebo and pentoxifylline were given to eight groups of rats prior to priapism being induced by a vacuum constrictive device for durations of 6 and 12 h, respectively. Half of the groups of rats that underwent the same duration of priapism (ischemic) were subjected to 1 h of detumescence after band removal (reperfusion). One group underwent no manipulation and no drug administration and served as a baseline determination (control). Corporeal homogenates were examined for lipid peroxidation (LP) derived malondialdehyde (MDA) accumulation via thiobarbituric acid assay. Results: MDA concentration differed significantly between VOP rats and controls (P < 0.001) but did not differ significantly between ischemic-only groups and reperfused groups (P > 0.05). In the pentoxifyllinepretreated groups, although MDA accumulation tended to be slightly lower than in the placebo groups, the difference was not statistically significant (P > 0.05) either in the 6- or 12-h duration priapic groups. Conclusions: LP, an indicator of radical oxygen metabolite (ROM) induced injury, occurs in rat corporeal tissue during and after abolishment of VOP. Single-dose pentoxifylline pretreatment failed to exert a protective effect on corporeal tissue in a rat model of VOP in terms of attenuation of LP.  相似文献   
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Background and Purpose:   

Management of rib fractures constitutes a major part of the trauma workload of any unit. Rib fractures result in disrupted chest wall mechanics and ventilatory insufficiency. The ability of a lung injury scoring system to predict the degree of respiratory dysfunction after rib fractures was evaluated.  相似文献   
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Between the years 1968-1988 30 patients with primary carcinoma of the fallopian tube were treated in the Department of Obstetrics and Gynecology of the University of Kiel. In 27 cases the initial treatment consisted of total abdominal hysterectomy and bilateral salpingo-oophorectomy. In 3 cases where the patients had undergone surgical treatment in another hospital a second operation for completion was performed. 2 patients received no further treatment after surgery. Postoperative radiotherapy was given to 20 patients and a combined treatment with radiation and polychemotherapy was implemented in 5 cases. Postoperative treatment in 3 patients was poly-chemotherapy alone. The 5-year-survival rate taking all tumor stages and modes of therapy employed into consideration was 36.7%. In analysing the survival rate for small numbers as directly related to postoperative treatment a 5-year-survival rate for radiotherapy of 35% (7/20) and for radiation therapy plus poly-chemotherapy of 40% (2/5) was found. After operative treatment followed by poly-chemotherapy alone one of three patients survived after 5 years.  相似文献   
10.
Abstract Fructosamine assay, which is used in diagnosing and monitoring diabetic patients, is compared with the hemoglobin and plasma glucose assays in children and adolescent insulin-dependent diabetes mellitus patients. We demonstrated that the gingival index scores were correlated with fructosamine values in insulin-dependent diabetes mellitus patients but not in non-diabetic controls. We also found that there was no correlation between gingivitis scores and fasting plasma glucose and HbAlc values. Periodontitis was found to be rare in diabetic children and adolescents.  相似文献   
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