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51.
Summary An immunoconjugate composed of natural interferon (nIFN) bound in a noncleavable fashion to a monoclonal antibody (MoAb) recognizing a breast epithelial membrane mucin (Mc5) was used to treat xenografts of a human mammary carcinoma cell line (MCF-7) growing in nude mice. The immunoconjugate (nIFN/Mc5) was administered as 20 intralesional (i.l.) injections to 1 of 2 xenografts in each animal. It was found that nIFN/Mc5 produced a significant enhancement of the growth inhibitory actions of nIFN on the injected tumors. Further enhancement was obtained when nIFN or nIFN together with Mc5 (at a dose 10 times larger than that present in nIFN/Mc5) were added to the immunoconjugate. Biodistribution experiments showed that the uptake of125I-nIFN/Mc5 by the tumors was greater and its elimination slower than for125I-nIFN alone or conjugated to irrelevant mouse IgG1. In addition, the immunoconjugate up-regulated the antigenic expression of a breast epithelial membrane mucin by the carcinoma cells, an up-regulation which was not significantly different from that produced by nIFN alone. The contralateral noninjected tumors exposed to systemic levels of the immunoconjugate showed an enhancement of antitumor effects, but to a lesser extent than the injected tumors. These findings suggest that the enhancement of the growth inhibitory action of the immunoconjugate was related to the specific binding of Mc5 which targeted the IFN to the carcinoma cells and impeded its elimination. It is likely that the targeting was favored by the IFN-mediated up-regulation of antigenic expression by the carcinoma cells, thereby producing a cascade of interrelated effects. The results of this study point out the feasibility and potential usefulness of IFN treatment by means of immunoconjugates as well as the worth of pursuing and improving this form of therapy.  相似文献   
52.
Objective To evaluate the long-term therapeutic effects of autologous peripheral blood st em cell transplantation (auto-PBSCT) on the treatment of hematological and soli d tumors. Methods Fifty-one patients were recruited in this auto-PBSCT study, in which several p otentially important parameters were studied including the optimal time for stem cell co llection, the dose of stem cell reinfusion, the time of hematopoietic reconsti tution, the disease free survival (DFS) and overall survival (OS), complication s related to transplantation, and maintenance chemotherapy after auto-PBSCT. Results After APBSCT, 3-year and 5-year survival rates of NHL were 83.3%; those of AM L were 74.7%; those of MM were 37.9% and 19%; those of ALL were 40% and 0% res pectively. Hematopoietic reconstitution was greatly promoted by granulocyte col ony stimulating factor (G-CSF). The mean time for patients’ neutrophil to reco ver up to >0.5×10(9) /L after APBSCT was 11.14 days in the group of the patien ts receiving G-CSF in contrast to 17.6 days in the group receiving no G-CSF. The most common complications of transplantation were fever, liver dysfunction and hypokalaemia, which were curable. No death was due to transplantation related complications.Conclusion Comparing with conventional chemotherapy, our study suggests that auto-PBSCT i s a very important therapeutic option that can significantly improve the prognos is in the patients with hematological and solid tumors, especially in the patien ts with AML and NHL.  相似文献   
53.
孤立性蝶窦病变的诊断与治疗   总被引:1,自引:1,他引:0  
目的;提高孤立性蝶窦病变的诊断和治疗率。方法;总结使用鼻窦内窥镜诊治孤立性蝶窦病变12例的全过程。结果:12例孤立性蝶窦病变的患者的均获准确诊断,使用鼻窦镜行经鼻腔蝶窦手术,有效率为83.3%,随访6 ̄24个月,10例无复发,复发2例二次手术后治愈;结论:孤立性蝶窦病变患者可用鼻窦内窥镜诊断与治疗。  相似文献   
54.
To approach the action of modified Yu Ping Feng Tang(玉屏风汤 Jade-Screen Decoction)on cellularimmunity,an experiment was conducted in mice under amputation-induced stress.On the 3rd dayafter amputation,acute atrophy was found in the thymus,the reactivities of T-and B-lymphocytes toCon-A and LPS were decreased,the IL-2 content and its activity reduced and the activity of NK cellslowered.The high,moderate and low concentrations of the modified Yu Ping Feng(YPF)Decoction allhave antagonistic action on the above manifestations of immune inhibition.  相似文献   
55.
人载脂蛋白E基因型测定方法的建立   总被引:4,自引:4,他引:0  
目的:建立一种准确、简便和经济的适用于大范围测定载脂蛋白E基因型的方法。方法:自中血中采用TKM法提取人基因组DNA,PCR-RFLP确定载脂蛋白E的基因型,硝酸银染色聚丙烯酰胺凝胶,若银染效果不佳可用硝酸脱色后重染。结果:TKM法获得DNA在产量和质量上均能满足PCR需求;电泳凝胶经银染可得清晰的DNA特异带,据此能准确确定样品载脂蛋白E的基因基因型;用硝酸溶液脱色后的凝胶经重染仍可得到清晰的图  相似文献   
56.
Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant–fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway.  相似文献   
57.
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields.  相似文献   
58.
在 30 只成年兔的下颌两切牙唇侧牙槽骨制备 10m m ×5m m 的开窗骨缺损,其表面覆盖 Gore Tex 膜。该膜分别于术后 1、2、3、5 周取出,以不放膜组为空白对照。所有动物5 周处死,标本作组织学分析。结果表明,2 周取膜组较空白对照组有更多的新骨形成,而 3 周或 5 周取膜组织的再生量无进一步增加。提示在引导兔开窗骨缺损的牙周再生中,屏障膜放置所需要的最适宜时间是 2 周。  相似文献   
59.
目的 :ABO亚型在临床输血中经常造成错定血型及输血反应 ,因而研制抗A1试剂血清是解决ABO亚型鉴定的主要途径。方法 :采用血型血清学特异性抗原抗体吸收实验。结果 :经大量反复实验 ,研制出特异性强 ,效价符合要求的抗A1试剂血清。结论 :抗A1血清是鉴定A亚型的专用试剂血清 ,对临床鉴定ABO亚型及安全输血有实用意义。  相似文献   
60.
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