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We successfully treated three patients using the flexible video cystoscope (CYF-240A, Olympus, Japan) for superficial bladder cancer under local anesthesia and/or spinal anesthesia. The major advantage of this new technique is that surgeons can use digital pictures and high frequency cauterization. This new system provides good quality of life for bladder cancer patients experiencing frequent recurrences.  相似文献   
74.
To investigate autologous antigen recognition, we developed two autoreactive CD4+ T-cell clones, A2 and A10, maintained with non-T cells and IL-2. Autologous non-T-cell stimulation of the T-cell clones resulted in a decrease in cell surface expression of CD4, whereas the expression of CD2, CD3, and WT31 was unchanged. Activation of the autoreactive T-cell clones by cell surface binding anti-CD3 MoAb, as a specific antigen stimulator of the T-cell receptor complex, induced cell surface antigen comodulation of CD3, CD4, and WT31. These data suggest a discrete association of CD3 and CD4 molecules in T-cell stimulation, acting through the autologous mixed lymphocyte reaction and the CD3/T-cell receptor complex. PMA treatment resulted in concomitant down-regulation of CD3 and CD4 but calcium ionophore treatment did not. Thus, it appears that phosphorylation of CD3 leads to the down-regulation of surface antigens of CD4.  相似文献   
75.
Incidence of damage to pacemaker and implantable cardioverter defibrillator leads is an emerging problem that should be prevented. The extrathoracic venipuncture approach has been suggested as a technique for venous access to avoid the problem. This report describes the method of double marker-guided venipuncture of extrathoracic subclavian and/or axillary vein. This approach achieves definite, safe, and speedy extrathoracic venipuncture and may be especially suitable for multiple lead placement for cardiac resynchronization therapy. (PACE 2004; 27[Pt. I]:818–820)  相似文献   
76.
RF catheter ablation was performed in 16 patients with nonreentrant idiopathic VT originating from the RVOT. All documented VT was monomorphic, but subtle morphological variation in the VT-QRS complex was observed in 10 (63%) of 16 patients. Through endocardial mapping, VT origin was determined within a narrow site (< 0.5 ± 0.5 cm) in 4 of the 10 patients with the morphological variation. In the other 6 of 10 patients, the origin extended to an area of > 0.5 ± 0.5 cm. In VT with morphological variation, the local electrogram at the site of VT origin also showed variation in morphology and activation sequence. For VT of narrow origin, RF application to the site eliminated the VT. However, in VT from a wide arrhythmogenic area, RF current had to be delivered to 3–7 distinct sites to cover the possible origin, and specific QRS configuration of VT and/or PVC was ablated at each of the earliest activation site. All but one VT were successfully ablated by RF current. Subtle morphological variation was frequent in this type of VT, and about half were associated with a wide arrhythmogenic area. Precise mapping and analysis of the efficacy of each BF application might be helpful to better understand the relationship between subtle changes of VT-QRS morphology and their origins.  相似文献   
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In order to assess the functional characteristics of the zone of slow conduction of reentrunt VT, rapid pacing was performed to entrain VT. The orthodromic conduction time was measured as the interval between the stimulus and the orthodromically captured electrogram recorded distal to the zone of slow conduction, hut not precisely at the exit point, and its response to rapid pacing was evaluated. In 32 of 33 consecutive patients, rapid pacing was performed to entrain VT. Of these, rapid pacing was repeated in 28 patients at 3–10 cycle lengths in steps of 10 msec before VT was terminated, or rapid pacing produced an acceleration of the rate. A pacing induced prolongation of the orthodromic conduction time (slowed conduction) was observed in 16 (57.1%) patients and in another 12 (42.9%) patients, the conduction time was constant. The pacing induced termination was observed in 93.8% of VT with slowed conduction and in 50% of VT with constant conduction, and the difference was significant (P < 0.05). There was no difference in the cycle length of VT or the shortest paced cycle length between VT with and without slowed conduction. The zone of slow conduction in human VT showed different conductive properties and VT with slowed conduction was associated with an easier and safer terminability with rapid pacing. The fact might be useful in selecting patients for antitachycardia pacing.  相似文献   
79.
We investigated the contribution of T cells in diffuse panbronchiolitis (DPB) by identifying T cell subsets in BALF of 36 patients with DPB, before and after long-term treatment with macrolide antibiotics, and 16 healthy control subjects. The percentages of lymphocytes and CD3+γδ+ cells in BALF of DPB patients and control subjects were similar, but the absolute number of these cells was higher in DPB patients. Treatment resulted in a significant reduction in the absolute number of these cells. A further two-colour analysis of T cell subsets in BALF showed a significantly higher ratio and number of CD8+HLA-DR+ cells in DPB patients. Treatment resulted in a significant reduction of activated T cells. Most BALF CD8+ cells were CD8+CD11b cytotoxic T cells. The number of these cells in BALF of DPB patients (26.69 ± 5.86 × 103/ml) was higher than the control (2.02 ± 0.38 × 103/ml; P< 0.001), and a significant reduction was observed after treatment (7.69 ± 2.59 × 103/ml; P< 0.01). The number of CD4+ cells was also higher in DPB patients than in controls, and most were CD4+CD29+ memory T cells. However, treatment did not influence the number of these cells. The number of lymphocytes, CD3+γδ+, CD8+CD11b, CD8+HLA-DR+, and CD4+CD29+ cells was higher in patients with bacterial infection than in those without bacterial infection, and interestingly, macrolide therapy reduced the number of lymphocytes, CD3+γδ+, CD8+CD11b and CD8+HLA-DR+ cells, irrespective of bacterial infection. In peripheral blood, the percentage of CD8+HLA-DR+ cells was also higher in DPB patients than in healthy subjects, and significantly decreased after treatment. The percentage of CD8+CD11b cells in peripheral blood was similar in DPB patients and normal subjects, and treatment significantly reduced the percentage of these cells. Finally, the expression of the adhesion molecules CD11a/CD18 (α/β-chains of LFA-1) on lung CD3+ cells and CD49d (α-chain of VLA) on lung CD4+ cells was enhanced compared with that on peripheral blood in DPB patients. Our results suggest that elevation of memory T cells and activation of CD8+ cells, mainly cytotoxic T cells, in the airway lumen of DPB patients may contribute to chronic bronchial inflammation, possibly through up-regulation of adhesion molecules. Our findings also indicate that macrolide antibiotics may have a direct or indirect suppressive effect on cytotoxic T cells, and as such, reduce inflammation and improve clinical condition.  相似文献   
80.
We investigated the effects of G-CSF in a granulocytopenic mouse model of Pseudomonas aeruginosa lung infection. The model was prepared by intratracheal instillation of the bacteria, while granulocytopenia was induced by intraperitoneal injection of 4.0 mg of cyclophosphamide (CPA). There was no difference in the survival rate between G-CSF-treated animals and the normal group, and the number of neutrophils in the blood and lung recovered to normal in the former group. However, the phagocytic and killing activities of neutrophils were lower in G-CSF-treated mice than in controls. Interestingly, the mortality rate increased significantly when anti-TNF-α antibody was combined with G-CSF, although it was intermediate between CPA alone and CPA–G-CSF-treated mice. However, the improved mortality was not associated with a change in the number of neutrophils in the circulation and lung. Administration of anti-TNF-α antibody resulted in a significant suppression of TNF-α in bronchoalveolar lavage fluid and of enhanced alveolar macrophage function (phagocytic and bactericidal activity) against P. aeruginosa in G-CSF-treated granulocytopenic mice. We showed also increased TNF-α mRNA expression and TNF-α production in vitro using G-CSF-pretreated alveolar macrophages compared with control untreated macrophages. Our results are the first evidence to suggest that G-CSF provides a synergistic protective effect against lethal P. aeruginosa lung infection in the granulocytopenic host. This effect is probably due to enhancement of alveolar macrophage function through endogenous TNF-α production, in addition to increasing the number of circulating neutrophils.  相似文献   
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