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41.
华乃震 《世界农药》2010,32(1):44-47
当使用常规助剂(碳-氢链组成)不能发挥药剂的药效时,使用特种(非碳-氢链组成的)助剂,能起到理想的效果。论述有机硅和氟碳两种特种助剂的性能和应用,并进行了特种助剂和常规助剂用于10%啶虫脒微乳剂后对蚜虫的室内毒力试验。结果表明,有机硅助剂和氟碳助剂单用都有明显增效作用,其中氟碳助剂OBS增效作用最大(91.70%),有机硅助剂次之(87%)。当氟碳助剂OBS与常规助剂JFC复配使用,发挥了最大协同增效作用(96.59%),远胜于氟碳助剂OBS单用和与其他助剂混用效果。  相似文献   
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The current immunotherapy strategies for triple negative breast cancer (TNBC) are greatly limited due to the immunosuppressive tumor microenvironment (TME). Immunization with cancer vaccines composed of tumor cell lysates (TCL) can induce an effective antitumor immune response. However, this approach also has the disadvantages of inefficient antigen delivery to the tumor tissues and the limited immune response elicited by single-antigen vaccines. To overcome these limitations, a pH-sensitive nanocalcium carbonate (CaCO3) carrier loaded with TCL and immune adjuvant CpG (CpG oligodeoxynucleotide 1826) is herein constructed for TNBC immunotherapy. This tailor-made nanovaccine, termed CaCO3@TCL/CpG, not only neutralizes the acidic TME through the consumption of lactate by CaCO3, which increases the proportion of the M1/M2 macrophages and promotes infiltration of effector immune cells but also activates the dendritic cells in the tumor tissues and recruits cytotoxic T cells to further kill the tumor cells. In vivo fluorescence imaging study shows that the pegylated nanovaccine could stay longer in the blood circulation and extravasate preferentially into tumor site. Besides, the nanovaccine exhibits high cytotoxicity in 4T1 cells and significantly inhibits tumor growth of tumor-bearing mice. Overall, this pH-sensitive nanovaccine is a promising nanoplatform for enhanced immunotherapy of TNBC.  相似文献   
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考察了A、B、C及D4种助燃剂对重油燃烧性能的影响。结果表明,在重油中添加适量的单剂及其复合剂,可以改善重油的燃烧效果,提高燃烧的火焰温度,提高燃料的发热量。在所考察的助剂添加比1∶1000~3∶1000内,加入助燃剂后的重油灰分含量均能满足重油质量指标,添加比1∶1000效果较好。在重油中添加适量的助燃剂,火焰温度提高25~86℃,而且试油火焰温度上升很快,并很快超过400℃。助燃剂B和助燃剂C对提高重油燃烧火焰温度效果明显。助燃剂B对提高重油热值效果较好。  相似文献   
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目的克隆大肠杆菌不耐热肠毒素B亚单位(ltB)基因,构建其原核表达质粒,并对表达产物进行活性鉴定。方法采用PCR技术从产毒大肠杆菌129株基因组DNA中扩增ltB基因,克隆入载体pET-32a(+)中,构建原核表达质粒pET-32a(+)-ltB,转化E.coli BL21(DE3),IPTG诱导表达,Ni2+-NTA树脂层析柱进行纯化,纯化产物采用ELISA法鉴定其与牛GM1的结合活性。结果重组表达质粒经菌落PCR鉴定证明构建正确,所克隆的ItB基因与GenBank中报道的相应核苷酸序列的同源性为99.9%。重组菌诱导4h,目的蛋白表达量最高,约占菌体总蛋白的25%。纯化的重组LTB蛋白纯度约为96%,具有与牛GM1特异性结合的生物学活性。结论已成功克隆了ltB基因,并构建了其原核表达质粒,表达的重组蛋白具有一定的生物学活性。  相似文献   
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目的探讨重组人IL-12真核表达载体(pcDNA6-p70)对核酸疫苗(HCMV pp65基因重组腺病毒,Adeno-pp65)的基因佐剂功能。方法pcDNA6-p70与Adeno-pp65共免疫BALB/c小鼠,每2周1次,共4次,同时设立Adeno-pp65对照组及生理盐水对照组。于初次免疫后第6周末尾静脉取血,第9周处死小鼠,分离脾细胞,分别检测细胞内细胞因子水平、CTL杀伤活性、特异性淋巴细胞增生和IFN-γ水平,并观察pcDNA6-p70对小鼠的安全性。结果共免疫组HCMV特异性CD4/IFN-γ、CD8/IFN-γ双标记阳性细胞的百分率均高于Adeno-pp65组及生理盐水对照组,差异均有显著意义;其CTL杀伤活性、HCMV特异性淋巴细胞增生水平及脾淋巴细胞特异性IFN-γ释放水平均高于Adeno-pp65组和生理盐水对照组,差异均有显著意义。pcDNA6-p70肌肉注射昆明小鼠,其体温、体重及一般情况与对照组差异均无显著意义。结论pcDNA6-p70与Adeno-pp65共免疫可提高核酸疫苗的免疫效果,且具有较好的安全性。  相似文献   
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目的:观察几种抗类风湿性关节炎(RA)药物对佐剂性关节炎(AA)大鼠关节软骨中的酸敏感离子通道(ASICs)表达的影响, 探讨抗RA药物对关节软骨的保护作用。方法:将大鼠随机分成正常组、AA模型组、阿司匹林(50 mg/kg)组、地塞米松(0.2 mg/kg)组、雷公藤多苷(50 mg/kg)组和左旋咪唑(10 mg/kg)组。弗氏完全佐剂(CFA)致炎后第10天起,AA大鼠出现继发性炎症, 此时地塞米松组腹腔注射地塞米松, 其它用药组分别灌胃相应的受试药物, 正常组与模型组灌胃等容量的无菌注射用水, 连续7d。实验结束后, 光学显微镜观察关节病理变化;用半定量RT-PCR和Western blotting分析常用药物对AA大鼠关节软骨细胞中ASICs表达的影响;用半定量RT-PCR方法分析常用药物对AA大鼠关节软骨中的蛋白聚糖体(aggregate proteoglycan, aggrecan)表达的影响;免疫组织化学技术检测常用药物对AA大鼠关节软骨中的Ⅱ型胶原蛋白合成的影响。结果:经过治疗后, 各用药组能明显抑制AA大鼠的继发性足肿胀。阿司匹林能显著抑制AA大鼠关节软骨细胞ASICs的表达, 其它用药组对ASICs无明显抑制作用。各用药组能明显升高AA大鼠关节软骨细胞基质成分Ⅱ型胶原和aggrecan表达量, 其中阿司匹林作用显著。结论:阿司匹林可能通过抑制ASICs的表达而抑制AA大鼠关节软骨的破坏。  相似文献   
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Objective:The aim of this study was to evaluate the effect of the excision repair cross-complementing (ERCC1) expression on survival in advanced gastric cancer patients who underwent surgical resection and treated with oxaliplatin-based adjuvant chemotherapy. Methods: Sixty-three patients who underwent surgical resection for cure and treated with oxaliplatin-based adjuvant chemotherapy were included in this study. The expressions of ERCC1 of gastric cancer were examined by immunohistochemistry and the patients were categorized into ERCC1-(+) and ERCC1-(-) groups. The relation between ERCC1 expression and survival of patients was examined. Results: Of the 63 eligible patients, 36 patients (57.1%) had tumor with a positive expression of ERCC1 and the remaining 27 patients had tumor with a negative ERCC1 expression. Expression differences of ERCC1 didn't correlated with age (P - 0.827), gender (P = 0.12), differentiation (P = 0.113), historical type (P = 0.942), site of tumor (P = 0.221), size of tumor (P = 0.608), stage (P = 0.815) and lymphatic invasion (P = 0.165). Overall survival (OS) was significantly longer in patients without ERCC1 expression, when compared to patients with ERCC1 expression (P = 0.023). Multivariate analysis revealed that ERCC1 expression significantly impacted on OS (MR: 4.049; P = 0.000). Conclusion: We concluded that resected and treated with oxaliplatin-based adjuvant chemotherapy gastric cancer patients without ERCC1 expression have a better survival when compared to patients with ERCC1 expression. ERCC1 expression will hopefully provide a rational basis for improving adjuvant chemotherapeutic strategies for gastric cancer patients. ERCC1, itself, may be a prognostic factor for gastric cancer.  相似文献   
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Ex vivo gene therapy using retrievable encapsulated cellular implants is an effective strategy for the local and/or chronic delivery of therapeutic proteins. In particular, it is considered an innovative approach to modulate the activity of the immune system. Two recently proposed therapeutic schemes using genetically engineered encapsulated cells are discussed here: the chronic administration of monoclonal antibodies for passive immunization against neurodegenerative diseases and the local delivery of a cytokine as an adjuvant for anti-cancer vaccines.  相似文献   
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