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61.
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   
62.
Overexpression of decoy receptor (DcR) 3 protein, a recently discovered member of the tumor necrosis factor receptor superfamily, was examined in 40 esophagogastrectomy specimens containing areas of Barrett esophagus (n = 27), low-grade dysplasia (n = 27), high-grade dysplasia or carcinoma in situ (n = 22), and esophageal adenocarcinoma (EAC; n = 28) with immunohistochemical analysis. The results revealed significantly more overexpression of DcR3 in high-grade dysplasia or carcinoma in situ and EAC than in benign esophageal mucosa (both P < .0001), Barrett esophagus (both P < .001), and low-grade dysplasia (P < .01 and P = .033, respectively). Low-grade dysplasia also showed significant overexpression of DcR3 compared with benign esophagus (P < .05) but not with Barrett esophagus (P > .05). DcR3 overexpression seems to negatively correlate with the grade of EAC. Our results suggest that overexpression of DcR3 protein might aid in the diagnosis of high-grade dysplasia or carcinoma in situ and EAC and also might serve as a potential therapeutic target.  相似文献   
63.
The immunohistological expression of placental alkaline phosphatase (PLAP) and PLAP-like enzyme was studied in frozen sections from a wide variety (n = 254) of normal and malignant tissues using monoclonal antibodies reactive with PLAP (H317) and PLAP/PLAP-like enzyme (H17E2; H315). PLAP/PLAP-like reactivity was seen in normal thymus, and foetal and neonatal testis, and in 21 out of 22 malignant germ cell tumours (GCTs), but was also found in normal endocervix, normal Fallopian tube and in 28 out of 167 non-GCTs (particularly in ovarian and proximal gastrointestinal tract tumours). Positivity for true PLAP (as demonstrated with H317) was seen in term placenta, in endocervix, and in Fallopian tube (but not in other normal tissues) and was commonly found in ovarian and proximal gastrointestinal tract tumours. Reactivity with H317 was unusual in malignant GCTs (2 out of 22 cases). These findings confirm that PLAP/PLAP-like positivity is a highly sensitive immunohistological marker for malignant GCTs, but one which by itself is of only moderate specificity. Furthermore, expression of true PLAP is rare in GCTs and favours instead an origin from the ovary or proximal gastrointestinal tract. The results also indicate that the predominant heat-stable alkaline phosphatase species in normal foetal and neonatal testis, and in thymus has a similar immunohistological profile to that found in malignant GCTs, and is a PLAP-like enzyme ("germ cell alkaline phosphatase") distinct from true PLAP. The occurrence of this marker in GCTs would appear to reflect increased eutopic production of an enzyme present in trace amount in corresponding normal tissues rather than a genuine example of ectopic expression.  相似文献   
64.
Direct protective effect of interleukin-10 on articular chondrocytes in vitro   总被引:14,自引:0,他引:14  
Objective To assess whether interleukin-10 (IL-10) is chondroprotective in vitro.Methods Chondrocytes were isolated from femoral cartilage of rats (7-10 days) by digesti on with collagenase Ⅱ.The first passage cells were grown in 24- well plates with DMEM, supplemented with 10% fetal bovine serum, for 2-4 days.The ce lls were then cultured in 0.1% fetal bovine serum DMEM medium, and given respec tively interleu kin-1 (IL-1) 100 μ/ml, IL-1 100 μ/ml+recombinant murine interleukin-10 ( rmIL-10) 20 ng/ml, rmIL-10 20 ng/ml, and cultured for 48 hours.Scanning el ectron morphology and immunohistochemical study of nitric oxide synthase 2 and matric metalloproteinase 3 mRNA in situ hybridization were performe d.Cell proliferation and morphology were observed under inverted microscope fr om the beginning of cell culture for three weeks.Results IL-1 stimulated granule production in the cytoplasma of chondrocytes, and the c ells died in the second and third weeks of culture.IL-10 antagonized IL-1, p rotected the cells from death and maintained chondrocyte proliferation.Scannin g electron morphology showed that IL-1 stimulated the formation of numerous mic rovilli on the cell surface, while thin and less numerous microvilli were found in cultures with IL-10.Immunohistochemical study and in situ hybridization sh owed that IL-10 inhibited NOS2 and MMP3 expression.Conclusion IL-10 not only inhibits the synthesis of inflammatory cytokines, but also direc tly protects chondrocytes by antagonizing IL-1.  相似文献   
65.
醒脑静注射液对脑出血病人高热昏迷的疗效观察   总被引:2,自引:0,他引:2  
目的:观察醒脑静注射液对脑出血病人高热与意识障碍的疗效。方法:按随机分组法将100例有高热与意识障碍的脑出血病人随机分为治疗组及对照组,治疗组在常规方法上加用醒脑静注射液,对照组采用常规方法。结果:治疗组恢复时间明显短于对照组。结论:醒脑静注射液对脑出血高热及意识障碍有明显治疗效果。  相似文献   
66.
为建立一种检测活细胞数的方法,作者采用三磷酸腺苷(ATP)生物荧光液闪测定法检测小鼠纤维瘤细胞株L929.ATP标准曲线工作范围为10 -9~10-5mol/ml,相关系数r=0.9963(P<0.001);当活细胞数在3×1 02~106个/ml时与发光计数值有良好的线性关系,r=0.9922(P<0.001),变异系数 CV = 1%~3%.用ATP生物荧光液闪测定法检测活细胞数灵敏、简便、准确、重复性好,用液闪计数仪即可完成测定,有较大的实用价值.  相似文献   
67.
S Liu  Z Peng  H Wang  J Lou  B He  Q Tang  D Qiu 《华西医科大学学报》2000,31(2):260-1, 268
The method for detecting the number of living cells was studied. Using an adenosine triphosphate (ATP) bioluminescence assay, the present authors reported a perfect linear relationship between lg ATP concentrations and lg luminescence counts (r = 0.9963) as well as a relationship between lg number of cells and lg ATP luminescence counts (r = 0.9922). The detectable cells ranged from 10(2) to 10(6) cells/ml, the coefficients of variation 1-3%. This method is simple, accurate and sensitive and has a high reproducibility.  相似文献   
68.
情感性精神障碍事件相关电位变异与自杀行为史的相关性   总被引:3,自引:0,他引:3  
探讨情感性精神障碍患者件相关电位变异的临床意义。方法收集39例抑郁相和22例躁狂相患者,以33例正常人为对照组,记录其事件相关电位P300和CNV。结论P300和CNV临床应用价值得到初步证实,自杀行为相关的生物学指标研究中需进一步重视。  相似文献   
69.
边缘性人格障碍与焦虑症的诱发电位比较   总被引:4,自引:0,他引:4  
目的 探讨边缘性人格障碍(BPD)和焦虑症(AN)在诱发电位中的特点。方法 收集27例BPD组,34例AN及52名正常成人对照组(NC),应用美国仪器以及光、声触刺激,完成视觉诱发电位(VEP)、听觉诱发电位(AEP)和体感诱发电位(要与NC相比,BPD组潜伏期VEP/P1、P2,AEP/P1,N2前移,波幅VEP/N1-P2,P3,AEP/P3,SEP/P3,P3增高但波幅VEP/P2-N2、P  相似文献   
70.
21纪我国医药行业的创新与发展   总被引:3,自引:0,他引:3  
在分析我国医药行业发展现状及存在问题的基础上,研究了加入WTO后医药行业所面临的机遇与挑战,以及当前医药企业技术创新存在的不足,提出了21世纪我国医药行业创新与发展的对策和建议。  相似文献   
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