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61.
口服耐受的机制及其在自身免疫病治疗中的应用   总被引:1,自引:0,他引:1  
口服耐受是指口服蛋白引起的一种免疫低反应状态。自Wel1sl911年首先报道这种现象以来,口服耐受引起了广泛关注,大量研究者发现给动物饲服蛋白质或绵羊红细胞后,再次消化道外免疫时,动物对这些抗原不再具有良好的反应性,而对其它抗原的反应正常[1]。免疫...  相似文献   
62.
Hyperekplexia is a rare, autosomal dominant neurological disorder characterized by hypertonia, especially in infancy, and by an exaggerated startle response. This disorder is caused by mutations in the ?1 subunit of the inhibitory glycine receptor (GLRA1). We previously reported two GLRA1 point mutations detected in 4 unrelated hyperekplexia families; both mutations were at nucleotide 1192 and resulted in the replacement of Arg271 by a glutamine (R271Q) in one case and a leucine (R271L) in the other. Here, 5 additional hyperekplexia families are shown to have the most common G-to-A transition mutation at nucleotide 1192. Haplotype analysis using polymorphisms within and close to the GLRA1 locus suggests that this mutation has arisen at least twice (and possibly four times). In 2 additional families, a third mutation is also presented that changes a tyrosine at amino acid 279 to a cysteine (Y279C). Five patients with atypical clinical features and equivocal or absent family history of hyperekplexia and 1 patient with a classical presentation but no family history are presented in whom a mutation in the GLRA1 gene was not detected. Thus, only clinically typical hyperekplexia appears to be consistently associated with GLRA1 mutations, and these affect a specific extracellular domain of the protein.  相似文献   
63.
注射吸毒致破伤风的临床特点及分析   总被引:1,自引:0,他引:1  
目的探讨注射吸毒致破伤风的诊断与治疗。方法回顾性分析了9例注射吸毒者破伤风的临床资料。结果9例注射吸毒致破伤风的病人中,5例治愈,4例死亡,死亡原因:3例因呼吸肌痉挛和分泌物过多阻塞呼吸道窒息死亡,1例因呼吸衰竭死亡。结论注射后皮肤和软组织感染可认为是引起破伤风外伤伤口。注射吸毒破伤风应按重症破伤风处理。及时气管切开或气管插管机械辅助呼吸可降低死亡率。  相似文献   
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本文综述常用抗偏头痛药物的药理学特点及临床应用。新药舒马坦具有理想的选择性抗偏头痛活性,布托啡烷等的经鼻喷雾用药系统为以前不能接受治疗的偏头痛患者提供一种新的给药途径,这些新的或正在 研究中的疗法将给临床医师提供治疗偏头痛患者更广泛的选择手段。  相似文献   
67.
Metal-catalyzed hydroxyl radicals are potent mediators of cellular injury, affecting every category of macromolecule, and are central to the oxidative injury hypothesis of Alzheimer disease (AD) pathogenesis. Studies on redox-competent copper and iron indicate that redox activity in AD resides exclusively within the neuronal cytosol and that chelation with deferoxamine, DTPA, or, more recently, iodochlorhydroxyquin, removes this activity. We have also found that while proteins that accumulate in AD possess metal-binding sites, metal-associated cellular redox activity is primarily dependent on metals associated with nucleic acid, specifically cytoplasmic RNA. These findings indicate aberrations in iron homeostasis that, we suspect, arise primarily from heme, since heme oxygenase-1, an enzyme that catalyzes the conversion of heme to iron and biliverdin, is increased in AD, and mitochondria, since mitochondria turnover, mitochondrial DNA, and cytochrome C oxidative activity are all increased in AD. These findings, as well as studies demonstrating a reduction in microtubule density in AD neurons, suggest that mitochondrial dysfunction, acting in concert with cytoskeletal pathology, serves to increase redox-active heavy metals and initiates a cascade of abnormal events culminating in AD pathology.  相似文献   
68.
Cantú syndrome (CS), characterized by hypertrichosis, distinctive facial features, and complex cardiovascular abnormalities, is caused by pathogenic variants in ABCC9 and KCNJ8 genes. These genes encode gain‐of‐function mutations in the regulatory (SUR2) and pore‐forming (Kir6.1) subunits of KATP channels, respectively, suggesting that channel‐blocking sulfonylureas could be a viable therapy. Here we report a neonate with CS, carrying a heterozygous ABCC9 variant (c.3347G>A, p.Arg1116His), born prematurely at 32 weeks gestation. Initial echocardiogram revealed a large patent ductus arteriosus (PDA), and high pulmonary pressures with enlarged right ventricle. He initially received surfactant and continuous positive airway pressure ventilation and was invasively ventilated for 4 weeks, until PDA ligation. After surgery, he still had ongoing bilevel positive airway pressure (BiPAP) requirement, but was subsequently weaned to nocturnal BiPAP. He was treated for pulmonary hypertension with Sildenafil, but failed to make further clinical improvement. A therapeutic glibenclamide trial was commenced in week 11 (initial dose of 0.05 mg–1 kg–1 day–1 in two divided doses). After 1 week of treatment, he began to tolerate time off BiPAP when awake, and edema improved. Glibenclamide was well tolerated, and the dose was slowly increased to 0.15 mg?1 kg?1day?1 over the next 12 weeks. Mild transient hypoglycemia was observed, but there was no cardiovascular dysfunction. Confirmation of therapeutic benefit will require studies of more CS patients but, based on this limited experience, consideration should be given to glibenclamide as CS therapy, although problems associated with prematurity, and complications of hypoglycemia, might limit outcome in critically ill neonates with CS.  相似文献   
69.
人FascDNA的克隆及其在大肠杆菌中表达的研究   总被引:1,自引:1,他引:1  
为获得高质量及充足的Fas蛋白,采用PCR技术调整Fas基因的开放阅读框架,使之与生物素化蛋白基因阅读框架一致;缺失了FascDNA基因的起始密码子并增加一个大肠杆菌偏性终止密码子,构建FascDNA和生物素化融合原核表达质粒PinPoint-Fas。将重组质粒转入大肠杆菌HB101,经500mmolIPTG在37℃条件下诱导4h,SDS-PAGE及Western印迹检测融合蛋白在大肠杆菌得以高效表达,表达量为细菌总蛋白的13.8%。用亲和层析树脂对生物素化融合蛋白进行亲和层析纯化,得到Fas重组的蛋白,且表达的Fas融合蛋白具有抗体结合活性。此蛋白的表达成功将解决Fas膜蛋白不易提取的难题,为深入研究Fas提供了良好材料来源  相似文献   
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