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11.
从兔网织红细胞提纯的红细胞分化调节因子(erythroid differentiation factor,EDF),能对体外培养的自发转化成纤维细胞系L929及人鼻咽癌细胞系KB产生作用。当EDF剂量为0.10μg/ml时,可引起L929细胞形态发生改变,并有细胞核固缩现象。第2d的细胞生长抑制率为64.86%,软琼脂集落形成率为0;第5d时细胞增殖为负值。~3H-TdR掺入率明显降低。EDF剂量为0.15μg/ml时,对KB细胞生长已有抑制作用。EDF剂量达0.30μg/ml时,生长抑制明显。以上结果证明了EDF对恶性细胞具有增殖抑制作用。这种作用对不同种类细胞敏感性不同,并且与剂量呈正相关。  相似文献   
12.
Pasteurella haemolyticaleukotoxin (LKT) is a member of the RTX family of pore-forming toxins that kill bovine immune cells. Several studies have suggested that RTX toxins kill target cells by the induction of apoptosis. In the present study, BL3 bovine leukaemia cells were exposed to LKT and assessed by molecular and flow cytometric techniques that measure different aspects of apoptotic cell death. The intoxicated cells demonstrated morphological, light scatter and Hoechst 33258 staining characteristics consistent with cells undergoing apoptosis. The cells also exhibited internucleosomal DNA fragmentation and poly (ADP-ribose) polymerase (PARP) cleavage, both indicators of apoptosis. LKT-treated cells bound annexin-V-FITC indicating that phosphatidylserine groups were translocated from the inner to the outer leaflet of the cell membrane. The effect of LKT on cells was dose dependent and inhibitable by incubation with anti-LKT monoclonal antibody. Finally, an early step for induction of apoptosis appears to be the binding of LKT to a β2 integrin since pre-incubating cells with anti-β2 integrin antibodies inhibited LKT-induced apoptosis. This study provides new insights into understanding the pathogenesis of bovine pasteurellosis and could lead to the development of both preventative and therapeutic strategies for disease management.  相似文献   
13.
Abundant evidence documents the highly proinflammatory actions of lysophosphatidylcholine (LPC). Further, LPC, found in high amounts in oxidized low-density lipoprotein (LDL), is implicated as an atherogenic factor. In endothelial cells, LPC impairs endothelial barrier function through GPR4, a novel receptor hypothesized to be sensitive to LPC and protons. The authors investigated the stimulation by LPC or low pH of GPR4 in human brain microvascular endothelial cells (HBMECs) and whether the activated GPR4 regulates in vitro monocyte transmigration. The results indicated that HBMECs stimulated by LPC (5 microM), but not low pH, showed a twofold increase in monocyte transmigration. Using retroviruses containing siRNA to GPR4, a > 60% reduction of GPR4 expression resulted in blockade of the LPC-stimulated transmigration. The inhibited response was restored by co-expression with an small interference RNA (siRNA)-resistant, but functional, GPR4 mutant construct. To investigate potential signaling mechanisms, the siRNA-mediated knockdown of GPR4 also prevented LPC-induced RhoA activation. C3 transferase, a Rho inhibitor, prevented approximately approximately 65% of the LPC-stimulated transmigration. LPC also increased MLC phosphorylation by 5 min, which was inhibited by the Rho kinase inhibitor, Y-27632 (10 microM) or ML-7 (myosin light chain kinase (MLCK) inhibitor). The findings indicate that the proinflammatory and atherogenic LPC stimulated endothelial GPR4, which promoted monocyte transmigration through a RhoA-dependent pathway.  相似文献   
14.
The diagnosis of autoimmune bullous diseases is based on clinical observation and on the presence of autoantibodies directed to molecules involved in the adhesion systems of the skin. Immunofluorescence assays are the currently accepted method for detection of autoantibodies; such assays depend greatly on the skill of operators and are difficult to standardize. Recombinant desmoglein-1 (Dsg1), Dsg3, and BP180 peptides, the main autoantigens in pemphigus or bullous pemphigoid, have been used to develop new quantitative enzyme immunoassays (EIA) for the detection of specific antibodies. The present study was undertaken to evaluate the sensitivity and specificity of these immunoassays and to determine the correlation between the results and the clinical aspects of diseases. Serum samples from patients with pemphigus vulgaris, pemphigus foliaceus, bullous pemphigoid, or mucous membrane pemphigoid, from healthy individuals, and from patients with unrelated autoimmune conditions were tested. Anti-desmoglein reactivity was detected in all the patients with pemphigus and in none of the controls. Patients with the more benign form of cutaneous disease had anti-Dsg1 antibodies, while patients with deeper cutaneous lesions or with mucosal involvement had anti-Dsg3 reactivity also, or exclusively. The BP180-based assay was positive for 66.6% of patients with bullous pemphigoid and for none of the patients with mucous membrane pemphigoid, and no reactivity was detected in the control sera. In conclusion, the anti-Dsg1 and anti-Dsg3 assays are useful in the diagnosis of pemphigus and provide information on the clinical phenotype of the disease. However, the sensitivity of EIA for detection of autoantibodies in bullous pemphigoid should be improved by the use of additional antigens or epitopes.  相似文献   
15.
Annals of Surgical Oncology - Black women with breast cancer have a worse overall survival compared with White women; however, no difference in Oncotype DX? (ODX) recurrence scores has been...  相似文献   
16.
Peanut allergy is one of the most severe food allergies due to its persistency and life-threatening character. Serum IgE from patients with documented peanut hypersensitivity reactions and synthetic peptides were used to screen the linear IgE-binding epitopes on the major peanut allergen, Ara h 1. Five major epitopes that bound peanut-specific serum IgE from more than 60% of patients tested were identified. Mutational analysis of the immunodominant epitope showed that single amino acid changes had dramatic effects on IgE-binding characteristics. Mapping and characterisation of the IgE-binding epitopes on Ara h1 could be used in future immunotherapeutic approaches for peanut allergy disease.  相似文献   
17.
高山红景天多糖对小鼠抗柯萨奇B5病毒感染能力的研究   总被引:11,自引:0,他引:11  
对感染柯萨奇B5病毒(CVB)小鼠模型研究结果表明,高山红景天多糖对发病小鼠心肌功能改善和免疫功能提高均具有明显的促进作用。增强了小鼠抗CVB5感染的能力,并对由CBV感染性疾病也有一定的防治作用。  相似文献   
18.
论述了IBM-PC及其兼容机之间的点点通讯,加装调制解调器通讯距离可达数公里。采用该技术可完成厂部与车间两级计算机系统的分级管理与控制。  相似文献   
19.
目的探讨残胃贲门癌手术切除,消化道重建的方法。方法总结1989年8月至1999年12月12例残胃贲门癌切除、空肠“9”字袢代胃及幽门重建术的治疗经验。结果无手术死亡,无倾倒综合征,无返流性食管炎。钡剂在“9”字环内有循环,下方重建凼门处有钡荆停留。全组均随访,随访时间最长4年3个月,最短4个月。其中1年内死亡2例,1~2年死亡4例,2~3年死亡2例,另4例生活良好。结论术后并发症少,有抗返流作用,利于营养支持,病人生活质量较高。  相似文献   
20.
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