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A mutation in exon 4 of the human alpha-synuclein gene was reported recently in four families with autosomal dominant Parkinson's disease (PD). In order to examine whether mutations in this exon or elsewhere in the gene are common in familial PD, all seven exons of the alpha- synuclein gene were amplified by PCR from index cases of 30 European and American Caucasian kindreds affected with autosomal dominant PD. Each product was sequenced directly and examined for mutations in the open reading frame. No mutations were found in any of the samples examined. We conclude that the A53T change described in the alpha- synuclein gene is a rare cause of PD or may even be a rare variant. Mutations in the regulatory or intronic regions of the gene were not excluded by this study.   相似文献   
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Naccache  PH; Jean  N; Liao  NW; Bator  JM; McColl  SR; Kubes  P 《Blood》1994,84(2):616-624
The control of the adhesive properties of human neutrophils is an essential element of their defense function. One level at which this control is exerted involves the upregulation of the surface expression of beta 2-integrins. In this study, we have examined the potential involvement of tyrosine phosphorylation in the latter process. Two inhibitors of tyrosine kinases with differing modes of action, erbstatin and herbimycin A, were found to inhibit the expression of CD11b and CD18 stimulated by chemotactic factors (fMet-Leu-Phe or leukotriene B4) or growth factors (tumor necrosis factor alpha). This inhibition was not shared by an inactive analog of erbstatin or by the protein kinase C inhibitor Ro 31-8330. Erbstatin also inhibited the unveiling of activation-specific neoepitopes detected by antibody CBRM1/5. Pretreatment of neutrophils (but not of endothelial cells) with erbstatin inhibited the stimulation of neutrophils' adherence to endothelial cells induced by fMet-Leu-Phe. Augmentation of tyrosine phosphorylation by inhibiting tyrosine phosphatases using hydroperoxyvanadate led to an increased surface expression of CD11b and CD18 and enhanced the adhesion of neutrophils to endothelial cells. Finally, the leumedin NPC 15669, which had previously been shown to inhibit stimulated CD11b expression and neutrophil adherence to endothelial cells and to exhibit anti-inflammatory properties in various in vivo models of inflammation, inhibited the stimulation of tyrosine, phosphorylation induced by fMet-Leu-Phe. Taken together, these data establish a strong correlation between tyrosine phosphorylation and integrin upregulation in stimulated human neutrophils.  相似文献   
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目的:观察经介入途径移植自体骨髓单个核细胞在股骨头坏死治疗中的应用,并评价其疗效。方法:选择2004-07/2005-11在解放军四六三院细胞治疗中心住院的,具有完整随访资料的股骨头坏死确诊患者共54例91髋。纳入确诊股骨头坏死,有关节疼痛、功能障碍等症状患者,性别、年龄不限;排除有严重心力衰竭、严重肾功能异常等不能耐受手术者。符合纳入标准54例,男45例,女9例,12~68岁。按ARCO分期Ⅱ期42髋,Ⅲ期47髋,Ⅳ期2髋。实验对象对治疗的相关内容知情同意并签知情同意。干预措施:抽取患者髂后上嵴骨髓进行单个核细胞悬液的制备。在DSA监视下将采集的单个核细胞混悬液经股动脉行Seldinger法穿刺,穿刺成功后,置入4F动脉鞘,经动脉鞘置入Cobra导管,将导管超选择至闭孔动脉及旋股内外侧动脉,平均注入单个核细胞悬液。术后定期随访症状变化情况,1年后复查X射线或CT,随访疼痛、关节活动度等情况。实验评估:①疼痛指数:无疼痛症状为3分,Harris髋关节评分疼痛分级A级;时有隐痛2分,Harris髋关节评分疼痛B级;轻度疼痛为1分,Harris髋关节评分疼痛C级;中度疼痛为0分,Harris髋关节评分疼痛D级。②功能指数:髋关节屈、伸、展、收、旋转度评分达Harris髋关节活动范围评分4~5分为3分;3~4分为2分;2~3分为1分;小于2分为0分。③X射线平片指数:股骨头形态无变化,应力骨小梁清晰,坏死区明显缩小为3分;坏死区略缩小为2分;治疗前后无明显变化为1分;坏死区扩大为0分。④血管指数:治疗后旋股内、外侧动脉及其分支增粗、增多,延长1cm以上者3分;1~0.5cm者2分;小于0.5cm者1分,无变化者0分。结果:54例患者均完成疼痛症状、关节功能及影像学随访1年。①术后12个月复查疼痛消失9髋,缓解61髋,无缓解21髋,缓解率为76.9%。②关节功能缓解33髋,无缓解58髋,缓解率为36.3%。③1年后X射线平片或CT、MRI示股骨头区可见不同程度的股骨头坏死区骨质密度改变,坏死区有吸收、缩小,股骨头形态变圆滑规整,改善28髋,无缓解或加重63髋,缓解率为30.1%。④12例24髋完成术后12个月复查股骨头供血动脉数字减影血管造影,好转18髋,好转率为72.2%。结论:经介入途径移植自体骨髓单个核细胞治疗股骨头坏死损伤小,可缓解临床相关症状。  相似文献   
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Green tea and black tea inhibit colon carcinogenesis in rats exposed to the cooked meat mutagen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). In the present investigation, green tea, black tea and (-)-epigallocatechin gallate (EGCG) were shown to block the production of oxygen free radicals derived from IQ in the presence of NADPH-cytochrome P450 reductase. In kinetic studies using IQ as tbe substrate and DMPO as a free radical spin trap, EGCG increased the Km of the reaction without altering Vmax, suggesting competitive enzyme inhibition (Ki=9.% mUM). This was confirmed in spectrophotometric studies using cytochrome c as the substrate, in which EGCG acted as a competitive inhibitor of NADPH-cytochrome P450 reductase (Ki=9.7 μM). These results suggest that the inhibitory activities of green tea and black tea in electron spin resonance assays using IQ as the substrate for the rednctase are related to an indirect effect on the enzyme rather than via direct scavenging of the free radicals. The possible implications of these findings are discussed in the context of pathways involved in the activation and detoxification of IQ in the colon.  相似文献   
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Airway and body surface sensors for triggering in neonatal ventilation   总被引:1,自引:0,他引:1  
Failure of neonatal patient triggered ventilation may reflect a delay in delivery of flow relative to the inspiratory effort of the infant. Transmission of diaphragmatic contraction to the sensor site (patient delay) and further transmission to and within the sensing device (device delay) both contribute to the delay in triggering. Patient and device delays were studied for different sensing systems in 36 infants, 24 of whom were intubated. Device delay was long (<40 ms) with a conventional apnoea monitor compared with sensors placed at the airway opening (2 ms), the inspiratory (12 ms) and expiratory (3 ms) pressure transducers of the ventilator, the Graseby capsule (8 ms), strain gauges (3 ms) and oesophageal pressure (6 ms). In near normal infants, the sum of patient and device delays for the latter sensors was less than 20 ms and a minor component of the total delay. However, in severe lung disease the total delay may be more than 100ms even for airway sensors.  相似文献   
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OBJECTIVE: Surgical aortic valvotomy has a long history of providing excellent palliation for aortic stenosis in infancy and childhood. The fate of aortic valve repairs for dominant aortic regurgitation in this same age group is considerably less clear. METHODS: From 1990 to 2000, a total of 21 patients underwent aortic valve repair for aortic regurgitation at our institution. Seventeen patients were younger than 17 years at the time of repair (3-17 years, mean 8.1 +/- 3.7 years). Of these 17 children, 6 (35%) had bicuspid valves and 11 (65%) had tricuspid valves. Type of repair varied with valve type, but repair generally consisted of commissure resuspension, partial commissure closure, triangular resection of redundant leaflets, or some combination. RESULTS: There were no deaths. Follow-up ranged from 1 to 11 years (mean 5.3 +/- 2.4 years). At present 3 of 17 (17.6%) have mild aortic regurgitation according to echocardiography and 6 (35.2%) have moderate aortic regurgitation. In 8 of 17 cases (47.1%) the repair clearly failed, requiring reoperation from 0.5 to 73 months after the original operation (mean 18.9 months). Reoperation consisted of 6 Ross procedures and 2 mechanical aortic valve replacements. There were no deaths at the secondary operation. CONCLUSION: Aortic valve repair in children with a dominant feature of aortic insufficiency tended to fail progressively and at a high rate. Leaflet thickening was associated with higher risk of repair failure in this series. The threshold for aortic valve replacement should remain low.  相似文献   
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