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131.
作者采用PCR方法克隆了我国海南省FCC1/HN株P190抗原两个保守区基因,分别定名为P190CRI和P190CRV。基因片段经纯化后连接到pUC18载体中进行DNA序列分析,结果显示:除了P190CRV中有5个碱基变换外,其余序列均与MAD20型序列一致。经序列分析的两个基因片段分别与pGEX-2T载体连接,经双酶切鉴定后转化感受态JM109(DE_3)大肠杆菌进行高效融合表达,并且用Sepharose 4B-谷胱甘肽层析柱进行亲和纯化,结果为:两个插入基因片段均得到高效融合表达,经一步亲和纯化后就取得高纯度的重组蛋白。  相似文献   
132.
目的 :用正交法优选复方决明子口服液的最佳工艺条件。方法 :以决明子中蒽醌的含量及浸出物的含量为指标 ,应用L9(3′)正交试验法优选复方决明子口服液的最佳工艺条件。结果 :最佳提取条件为 :加 1 0倍量水 ,煎煮 3次 ,每次 1 .5h。结论 :优越工艺验证表明 ,最佳提取工艺为A1 B2 C1 。说明优选工艺稳定可靠。  相似文献   
133.
Purpose: We examined whether bone marrow-derived dendritic cells (DCs) could induce antitumor immunity when a chemotherapeutic drug was added. Methods: CT26 (a murine colon cancer cell line syngeneic with BALB/c) and CT26-bearing mice were treated with mitomycin C (MMC) intraperitoneally (i.p.). Next, mice immunized with a coinjection of DCs and MMC-treated CT26 (i.p.) were given an intradermal inoculation of CT26. Finally, CT26-bearing mice were treated with MMC (i.p.) with or without DCs, given peritumorally. Results: Although the inoculated tumor was not rejected in the control mice, CT26 was rejected in 50% of the mice injected with MMC alone. Apoptosis was observed in the MMC-treated CT26 cells in vitro and in vivo. Immunization with DCs and apoptotic CT26 cells, but not with apoptotic CT26 alone, gave protection against tumor challenge in 7 of 13 mice. A significantly higher level of cytotoxic T-cell activity and interferon-γ production was seen in the protected mice. When MMC (i.p.) treatment was followed by peritumoral DC injection in the CT26-bearing mice, remarkable therapeutic effects were observed. Conclusion: DCs can collaborate with chemotherapy-induced apoptotic tumor cells and elicit improved antitumor immunity, probably through the acquisition of tumor-associated antigens from apoptotic tumor cells. Received: January 7, 2002 / Accepted: September 3, 2002 Acknowledgments. We thank Dr. Kazuo Kinoshita for his useful advice on using flow cytometry. This research was partly supported by the Ministry of Education, Culture, Sports, Science and Technology (No. 11671160). Reprint requests to: S. Yamasaki  相似文献   
134.
目的 观察小剂量卡介苗(BCG)、丝裂霉素C(MMC)交替灌注预防浅表性膀胱癌术后复发的疗效和安全性。方法 回顾性分析自2000年5月~2001年6月的45例浅表性膀胱癌患的临床资料,29例行膀胱部分切除术,16例行经尿道膀胱肿瘤电切术(TuRBt),术后定期应用卡介苗60mg、丝列霉素C 10mg交替膀胱灌注,每周1次共6次,间歇3个月,再每月1次,持续12个月。其中Ta、T1期22例、T2期23例。结果 所有病人随访12~24个月,45例患中,共有2例复发,均为TURBt后T2病人,总有效率95.2%,无全身不良反应,仅2例应用BCG后出现轻度膀胱刺激症状。结论 小剂量MMC、BCG交替膀胱内灌注,预防浅表性膀胱癌术后复发,效果好、病人耐受性强、副作用小。  相似文献   
135.
Failure of oral implants: aetiology, symptoms and influencing factors   总被引:1,自引:0,他引:1  
The use of oral implants opened a wide range of prosthetic treatment possibilities in edentulous patients. Although the reported success rates of oral implants are high, failures do occur. This paper reviews the current knowledge about the aetiology, the signs and symptoms and the possible influencing factors of implant failure. Possible causes of implant failure are thought to be infection of the periimplant tissues, occlusal overload, or a combination of both. Nevertheless, pinpointing one of these as the aetiological factor in a particular case is difficult and should be handled reluctantly. Although the cause might seem obvious, influencing factors could play a role as well. Gaining insight into these processes might stimulate the adoption of preventive action and therefore increase the predictability of the treatment outcome with oral implants. Received: 4 April 1997 / Accepted: 27 November 1997  相似文献   
136.
A rare case of lentigo maligna in the oral cavity was investigated by light and electron microscopy. Cutaneous lentigo malignas often develop to malignant melanomas. However, the electron microscopic examination revealed that even though there were a large number of melanosomes, most of them were late stage and had membrane structure, and positive staining with HMB-45 was not recognized. From our findings, it is difficult to conclude that oral lentigo malignas develop malignant melanomas, and thus further studies are needed.  相似文献   
137.
采用大肠菌群作为卫生指示菌,对口服药品进行细菌学检验,实验结果表明有利于口服药品染菌状况的监督与控制。  相似文献   
138.
Cattle were vaccinated either with a single recombinant tick antigen, Bm86 or with a combination of two recombinant antigens, Bm86 and Bm91 from the tick Boophilus microplus . In three experiments, the responses of cattle to subsequent challenge with the tick were assessed. The addition of the Bm91 antigen enhanced the efficacy of the vaccination over that with Bm86 alone to a statistically significant degree. Moreover, co-vaccination with two antigens did not impair the response of cattle to the Bm86 antigen. Finally, responses of individual cattle to the two antigens were independent. All of these results may be relevant to the increase in efficacy expected from a dual antigen vaccine.  相似文献   
139.
江苏省肾综合征出血热单价灭活疫苗中期免疫效果观察   总被引:5,自引:2,他引:3  
观察HFRS单价灭活疫苗中期免疫效果。方法:采用IFAT法及MCPENT法检测荧光抗体及中和抗体。结果:3个试区加强接种人数分别为4052、4407和6354人。加强后,Ⅰ型苗荧光抗体阳性率为72.73%,GMT为14.14;中和抗体阳性率为54.55%,GMT为6.67。D型苗荧光抗体阳性率为75.00%,GMT为11.85;中和抗体阳性率为60%,GMT为9.44。加强后1年,Ⅰ型苗年均保护率为65.52%,Ⅱ型苗则为94.24%。同期,Ⅰ型苗荧光抗体阳性率维持在40%,中和抗体维持在35.00%;Ⅱ型苗荧光抗体阳性率降至10.34%,中和抗体维持在53.85%。结论:两型疫苗均有较好的中期防病效果。  相似文献   
140.
通过对金锁匙口服液的药效学及毒性的研究表明:本品能明显抑制吗啡依赖性小白鼠停药后的跳跃反应,协同戊巴比妥钠催眠作用,提高小鼠热板法痛阈值,抑制醋酸引起的小鼠扭体反应,提示金锁匙口服液对吗啡类成瘾患者有一定的治疗作用,毒理研究表明;本品服用无药物依赖性、安全、无毒。  相似文献   
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