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91.
报道了用免疫、电生孔和纳米TiO2光催化组合技术进行杀伤结肠癌LoVo细胞的研究. 先把结合LoVo细胞表面CEA抗原的单克隆抗CEA抗体吸附在纳米TiO2微粒表面, 抗体-纳米TiO2复合微粒就会自动吸附到LoVo细胞的表面, 然后用电脉冲法使LoVo癌细胞的细胞膜上产生小孔, 促使纳米TiO2微粒进入癌细胞内部. 最后在紫外光照射下使TiO2纳米粒子在癌细胞内部发生光催化氧化作用, 杀伤癌细胞. 结果表明, 这种组合技术具有很高的杀癌细胞能力. 在仅含3.12 μg/mL抗体-纳米TiO2的细胞培养液内和强度为4 mW/cm2的紫外光照射下, 可在30 min内将所有LoVo癌细胞杀死. 这种技术对LoVo癌细胞的杀伤力远高于对不表达CEA抗原的人正常TE353.sk细胞的杀伤力, 显示了组合技术杀癌细胞的高选择性. 因此, 这种组合技术有望成为治疗癌症的新方法, 值得进一步探索.  相似文献   
92.
羊栖菜多糖对小鼠免疫功能的影响   总被引:4,自引:0,他引:4  
采用从羊栖菜提取物分离获得的 4个组分中选择其中不同分子量 ,且得率较高的F1、f1组分 ,观察它们对小鼠免疫功能的影响 .结果显示按 4 0mg/(kg·d)剂量腹腔注射 7d后 ,对小鼠抗SRBC抗体生成有促进作用 ,同时明显提高小鼠脾指数 ,其中f1组最明显 .对f1组分按不同剂量注射 ,结果显示对小鼠胸腺T淋巴细胞增殖促进作用呈明显量效关系 .  相似文献   
93.
微量元素与人体健康   总被引:8,自引:1,他引:7  
讨论了微量元素与人体健康的关系及其在体内的代谢平衡问题,包括:铁的生理功能,硒的免疫功能,铅的毒害作用。  相似文献   
94.
The advancements in the field of nanotechnology have provided a great platform for the development of effective antiviral vaccines. Liposome-mediated delivery of antigens has been shown to induce the antigen-specific stimulation of the humoral and cell-mediated immune responses. Here, we prepared dried, reconstituted vesicles (DRVs) from DPPC liposomes and used them as the vaccine carrier system for the Middle East respiratory syndrome coronavirus papain-like protease (DRVs-MERS-CoV PLpro). MERS-CoV PLpro emulsified in the Incomplete Freund’s Adjuvant (IFA-MERS-CoV PLpro) was used as a control. Immunization of mice with DRVs-MERS-CoV PLpro did not induce any notable toxicity, as revealed by the levels of the serum alanine transaminase (ALT), aspartate transaminase (AST), blood urea nitrogen (BUN) and lactate dehydrogenase (LDH) in the blood of immunized mice. Immunization with DRVs-MERS-CoV PLpro induced greater antigen-specific antibody titer and switching of IgG1 isotyping to IgG2a as compared to immunization with IFA-MERS-CoV PLpro. Moreover, splenocytes from mice immunized with DRVs-MERS-CoV PLpro exhibited greater proliferation in response to antigen stimulation. Moreover, splenocytes from DRVs-MERS-CoV PLpro-immunized mice secreted significantly higher IFN-γ as compared to splenocytes from IFA-MERS-CoV PLpro mice. In summary, DRVs-MERS-CoV PLpro may prove to be an effective prophylactic formulation to prevent MERS-CoV infection.  相似文献   
95.
In this paper, a new learning algorithm based on group method of data handling (GMDH) is proposed for the identification of Takagi-Sugeno fuzzy model. Different from existing methods, the new approach, called TS-GMDH, starts from simple elementary TS fuzzy models, and then uses the mechanism of GMDH to produce candidate fuzzy models of growing complexity until the TS model of optimal complexity has been created. The main characteristic of the new approach is its ability to identify the structure of TS model automatically. Experiments on Box-Jenkins gas furnace data and UCI datasets have shown that the proposed method can achieve satisfactory results and is more robust to noise in comparison with other TS modeling techniques such as ANFIS.  相似文献   
96.
A triazole-linked β-glucan analogue was prepared using a copper-catalyzed azide-acetylene coupling reaction. The alkynylsilyl moiety was inactive under the conditions of the copper-catalyzed azide-acetylene coupling reaction and was readily converted into a terminal acetylene group by treatment with tetrabutylammonium fluoride. Using the method, we successfully synthesized a β-glucan analogue containing three laminaripentaose units.  相似文献   
97.
Lyme disease (LD) is the most common tick‐borne disease in Europe, North America, and Asia. The etiologic agents of LD are spirochetes of the group Borrelia burgdorferi sensu lato, which possess a lipid content of 25–30 % of the dry weight. The major glycolipid cholesteryl 6‐O‐acyl‐β‐D ‐galactopyranoside (ACGal), present in B. burgdorferi sensu stricto, B. afzelii, and B. garinii, is a specific and highly prevalent antigen frequently recognized by antibodies in late‐stage LD. Here we report a convenient route for the chemical synthesis of ACGal by employing a combination of chemical synthesis steps with enzymatic transformations. This synthesized molecule was compared with bacterial extracts by immunoblots with patient sera, confirming the preserved antigenicity. Next, a glycolipid library derived from the native molecules with variations in the fatty acyl moiety and derivatives in which the cholesterol has been replaced was designed and synthesized. The chemical structures were confirmed by 1D and 2D NMR spectroscopy and mass spectrometry. The native and synthetic glycolipids were utilized in immunoblots to determine the epitope recognized by antibodies in patient sera. By this method we could demonstrate that galactose, cholesterol, and a fatty acid with a minimal chain length of four carbon atoms comprises the essential structure for recognition by antibodies. Finally, this finding allowed the synthesis of a functionalized ACGal with an ω‐mercapto group at the fatty acid and a facile protection and deprotection strategy. This antigenic hapten can be conjugated to a carrier protein to effect immunization against Lyme disease.  相似文献   
98.
Hemagglutinin-neuramidinase(HN) is one of the most important surface structure proteins of the Newcastle disease virus(NDV). HN not only mediates receptor recognition but also possesses neuraminidase(NA) activity, which gives it the ability to cleave a component of those receptors, NAcneu. Previous studies have demonstrated that HN has interesting anti-neoplastic and immune-stimulating properties in mammalian species, including humans. To explore the application of the HN gene in cancer gene therapy, we con...  相似文献   
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