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61.
目的 :通过对 2 3例顽固性室性早搏 (简称室早 )的射频消融分析 ,探讨室早的心电图特点、消融方法及效果 .方法 :男性 16例 ,女性 7例 ,均为频发、药物难治、症状明显的顽固性单形性室早患者 ,年龄(4 4 4± 9 6 )岁 .采用起搏标测和激动顺序标测 ,前者以起搏时与室早QRS波形态完全相同点为消融靶点 ,后者以早搏时最早心室激动点为消融靶点 .2 3例中 17例室早起源于右室 ,4例起源于左室 .消融即刻成功率86 9% ,累积放电 (930 4± 72 5 )s,成功者行动态心电图检查记录消融前后室早数为 (5 6 71± 2 4 36 )次 / 2 4h和 (39± 5 2 )次 / 2 4h (P <0 0 1) .随访 (2 3 2± 12 3)月 ,未服任何抗心律失常药 ,无 1例复发及并发症发生 .结论 :射频消融可有效而安全地消除单形性室早 ,采用粗标激动顺序、精标起搏图形 ,多点、长时间、高功率放电可提高成功率 ,降低复发率 ,可作为症状严重、药物无效或不能耐受患者的治疗选择  相似文献   
62.
目的观察高迁移率族蛋白B1(HMGB1)对树突状细胞(dendritic cells,DC)表面共刺激分子表达的影响,并对其机制进行初步探讨。方法分离正常Wistar大鼠脾脏DC后置于96孔培养板(1×10~5/孔),采用HMGB1刺激,观察HMGB1刺激与DC表面共刺激分子CD80、CD86和主要组织相容性复合物(MHC)Ⅱ表达的时间-效应关系及剂量-效应关系。结果HMGB1刺激后,DC表面共刺激分子CD80、CD86和MHCⅡ表达分别于24~72 h明显上调(P<0.05,0.01),其中以作用48 h后DC表面共刺激分子表达上调尤为显著(P<0.01);0.1μg/ml、1μg/ml、10μg/ml的HMGB1刺激均可诱导DC表面共刺激分子CD80、CD86和MHCⅡ表达增强(P<0.05,0.01),其中HMGB1的浓度在1μg/ml时,大鼠DC表面共刺激分子CD80、CD86和MHCⅡ的表达增强最明显(P<0.01)。结论HMGB1能诱导DC表面共刺激分子表达增强,HMGB1可能是诱导DC成熟的免疫刺激信号。  相似文献   
63.
用McAb和ABC法测定了38例慢性再生障碍性贫血(CAA)患者外周血T淋巴细胞亚群(简称T亚群)。与健康人相比,CAA的Ts明显增高(P<0.001),Th/T5明显降低(P<0.001)。并发现外周血Hb水平、病程、疗效及中医证型与T亚群相关。按气血两虚肾阳虚、肾阴虚、肾阴阳两虚的顺序,患者Th逐渐降低,Ts逐渐升高,Th/Ts明显降低。后两组比前两组Th/Ts下降更显著(P<0.01),提示阳损及阴时机体免疫机能发生更大的改变,从T亚群水平揭示了中医证型特别是肾阳虚、肾阴虚的内涵。  相似文献   
64.
The subcellular localization of the inositol 1,4,5-trisphosphate receptor protein, P400, was studied in the vestibular complex, an area to which Purkinje cells project, as well as in neurons of the dorsal cochlear nucleus and in ectopic Purkinje cells of adult rat brain. The receptor was demonstrated by electron microscopical immunocytochemistry using the avidin-biotin peroxidase complex procedure, with the monoclonal antibody 4C11 raised against mouse cerebellar inositol 1,4,5-trisphosphate receptor protein. Immunoreactivity was found in preterminal fibres and terminal boutons in the nuclei of the vestibular complex, generally associated with the subsurface systems and stacks or fragments of smooth endoplasmic reticulum. Ectopic Purkinje cells and cartwheel cells of the dorsal cochlear nucleus also displayed immunoreactivity, but this was much less intense in the latter. The results of the present study suggest that this receptor protein, involved in the release of Ca2+, is located in sites that enable it to influence the synthesis, transport and release of neurotransmitters.  相似文献   
65.
We have studied the ability of synthetic analogs of lipid A to mimic lipopolysaccharide (LPS) for activation of 70Z/3 pre-B cells (expression of surface Igs) or to antagonize this effect. The results indicate that the presence of glucosamine (mono- or disaccharide) as a 'backbone' for the attachment of fatty acids is not necessary for activation of cells of the B lineage. Phosphate groups are not necessary either. Other structural features such as the configuration of particular asymmetric carbons, and the distance between an anionic group and an N-acyl chain, seem to be much more critical parameters for activation of B cells. Among the synthetic lipids which were unable to activate 70Z/3 cells, one compound, consisting of N,N-acylated and bisphosphorylated 2,3-dideoxy-2,3-diamino-D-glucose, behaved as a specific LPS antagonist and blocked also the activation triggered by the other synthetic inducers. The influence of the synthetic lipids on the entry of mature mouse B lymphocytes into the G1A phase of the cell cycle (cell enlargement) was also investigated. A high correlation was observed between the potency to activate pre-B cells and the ability to induce blast formation in mature B cells.  相似文献   
66.
Long-term clinical and functional outcomes for patients undergoing foot and ankle amputations are not well documented. We attempted to document long-term outcomes for patients who required lower extremity amputations as a result of wounds suffered during wartime. For this study, 27 Iranian soldiers who had wounds requiring amputation of the foot and ankle were selected for follow-up. The participants' wartime medical records were reviewed, a clinical examination was performed, and each participant completed a questionnaire. Postamputation follow-up averaged 17.5 years. The most prevalent (66.6%) cause of injury was a land mine. The prevalences of different clinical symptoms reported by the amputees at the time of the last follow-up were as follows: 11 (40.7%) with phantom sensation, 6 (22.2%) with phantom pain, 12 (44.4%) with stump pain, 12 (44.4%) with back pain, 9 (33.3%) with contralateral knee pain, and 4 (14.8%) with ipsilateral knee pain; 20 (74%) reported treatment for psychological conditions. In regard to social conditions, 13 (48.1) were currently employed, or had been employed, for a number of years after the amputation; 26 (96%) had children, and all of the patients were married. The results of this observational study indicate that individuals have significant long-term pain and discomfort after war-related lower extremity amputation. Although all 27 (100%) of the amputees were able to maintain satisfactory family functioning, only 13 (48.1%) of the study participants were able to remain productively employed after undergoing amputation, and 20 (74%) reported long-term psychological problems in addition to their physical pain.  相似文献   
67.
BACKGROUND: Suprasphincteric fistulae remain the most difficult to cure. OBJECTIVES: The purpose of this study was to evaluate the healing rate of suprasphincteric anal fistula treated by ano-cutaneous advancement flap repair, and the impact of this procedure on continence and quality of life. METHOD: Sixteen patients with complex, recurrent or chronic suprasphincteric fistulae associated with significant tissue damage (necrotizing fasciitis, keyhole deformity and anal stenosis) or who had failed previous surgical procedures were treated by ano-cutaneous flap closure. They were assessed pre and postoperatively by the treating surgeon for wound healing and fistula recurrence and later followed up by phone interview using the St Mark's Hospital incontinence score and the Perianal Disease Activity Index (PDAI) as indicators of treatment outcome. RESULTS: Fifteen patients had successful healing of their fistula with the cutaneous flap, with recurrence in only one. The most common short-term complications were minor graft site wound separation, which healed in all cases without intervention, and wound pain, which settled over time and was not associated with recurrence. Continence improved for almost 70% of the patients, with a significant reduction in St Mark's incontinence scores (t = 2.62, 15 d.f., P = 0.02). PDAI also decreased significantly (t = 7.55, 15 d.f., P < 0.001), demonstrating improvement in quality of life for most patients. CONCLUSION: Ano-cutaneous flap can achieve healing of complex and recurrent suprasphincteric anal fistula in patients who had previously failed at other forms of treatment thus improving their quality of life and continence.  相似文献   
68.
69.
Tritium was introduced into the new orally active, selective phosphodiesterase type V (PDE V) inhibitor vardenafil (Levitra®), by reduction of a suitable amide precursor with freshly prepared lithium aluminum tritide. A specific activity of 52.7 Ci/mmol (1.95 TBq/mmol) was achieved. In order to overcome the usual technical difficulties during the preparation of complex tritides a new and easy labeling technique which has considerable potential for various tritia‐tion procedures, was developed. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
70.
Despite the fact that both H-2K and D molecules are up-regulated in the central nervous system (CNS) following Theiler's murine encephalomyelitis virus (TMEV) infection, resistance in this virus model of multiple sclerosis maps exclusively to D. To address this paradox, we examined the ability of the K and D molecules to present viral antigens to cytotoxic T lymphocytes (CTL). Whereas no virus-specific CTL were detected in the CNS of susceptible B10.Q and B10.S mice 7 days post-infection, D-restricted CTL were identified readily in the CNS of resistant B10 animals. There was no evidence of K-restricted CTL in the CNS of B10 mice at day 7 post-infection. The presence of both K- and D-restricted virus-specific CTL in the spleen of immunized B10 mice demonstrates that the exclusive use of D molecules by CTL in the CNS of mice 7 days post-infection is not due to the inability of the K molecules to present viral peptides to lymphocytes. We conclude that the prominent role of the D locus in determining resistance or susceptibility to TMEV-induced demyelination is determined by factors governing the regulation of the immune response, and not by the presence or absence of CTL precursors capable of recognizing viral peptides presented by the K and D antigen-presenting molecules, or by differences in the ability of the K and D molecules to present viral peptides.  相似文献   
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