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41.
利用生产清水玉米笋罐头的废品原料——未受粉的玉米笋须,进行玉米笋须饮料的开发研制,探讨了影响生产工艺的因素,制定了可行的生产工艺条件及质量标准。 相似文献
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Synthetic Modular Antibody Construction by Using the SpyTag/SpyCatcher Protein-Ligase System 下载免费PDF全文
Dr. Md Kausar Alam Carolina Gonzalez Wayne Hill Dr. Ayman El-Sayed Dr. Humphrey Fonge Dr. Kris Barreto Prof. Dr. C. Ronald Geyer 《Chembiochem : a European journal of chemical biology》2017,18(22):2217-2221
Efforts to engineer recombinant antibodies for specific diagnostic and therapy applications are time consuming and expensive, as each new recombinant antibody needs to be optimized for expression, stability, bio-distribution, and pharmacokinetics. We have developed a new way to construct recombinant antibody-like “devices” by using a bottom-up approach to build them from well-behaved discrete recombinant antibody domains or “parts”. Studies on antibody structure and function have identified antibody constant and variable domains with specific functions that can be expressed in isolation. We used the SpyTag/SpyCatcher protein ligase to join these parts together, thereby creating devices with desired properties based on summed properties of parts and in configurations that cannot be obtained by using genetic engineering. This strategy will create optimized recombinant antibody devices at reduced costs and with shortened development times. 相似文献
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Geoffrey Haddou Jany Dandurand Eric Dantras Huynh Maiduc Hoang Thai Nguyen Vu Giang Tran Huu Trung Philippe Ponteins Colette Lacabanne 《应用聚合物科学杂志》2019,136(23):47623
This study is devoted to the analysis of the properties of continuous bamboo fiber (BF)-reinforced polyamide 11 (PA 11) composites. The SEM observations highlighted continuity between BFs and the polymeric matrix showing a high density of hydrogen bonds. The comparative calorimetric study of the matrix and its composites showed that the crystallinity of PA 11 was not modified by the presence of bamboo fibers. The physical aging observed in PA 11 is no more observed in composites due to physical interactions between PA 11 and BFs. The mechanical properties were investigated by tensile strength and dynamic mechanical analysis. The introduction of BFs enhanced Young's modulus of the matrix by a factor of 10. The presence of BFs also improved the storage shear modulus G′ over the whole temperature range. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47623. 相似文献
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Construction and optimization of trans‐4‐hydroxy‐L‐proline production recombinant E. coli strain taking the glycerol as carbon source 下载免费PDF全文
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Recombinant buckwheat trypsin inhibitor (rBTI) was studied to evaluate if it could enter cancer cells and to determine the mechanism. Fluorescein isothiocyanate-labelled buckwheat trypsin inhibitor (FITC-BTI) entered Hep G2 cells in a concentration-dependent manner. FITC-BTI colocalised with labelled transferrin (Tf) in the punctate structure, implying that rBTI enters Hep G2 cells by clathrin-dependent endocytosis. Incubation of Hep G2 cells with different chemical inhibitors abolished diffuse, but not punctate fluorescence, thus indicating that membrane potential plays a critical role in this process. Impairment of clathrin-mediated endocytosis by RNAi with clathrin heavy chain greatly reduced or completely abolished both diffuse and punctate fluorescence, further supporting a theory of a single route of endocytosis. Consistent with our working hypothesis, Hep G2 cells which were arrested in the M phase did not show any vesicular or diffuse FITC-BTI. We conclude from these results that both endocytosis and membrane potential are required for rBTI entry into Hep G2 cells. 相似文献
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目的 探讨重组人促红细胞生成素(recombinant human erythropoietin,rh-EPO)对人乳腺癌MDA-MB-231细胞增殖的影响及其作用机制.方法 将人乳腺癌 MDA-MB-231 细胞进行培养.传至5~6代,细胞生长状态稳定后,收集人乳腺癌 MDA-MB-231细胞用于MTT实验.采用MTT法检测 5 组(阴性对照组、rh-EPO A 组、rh-EPO B组、rh-EPO C 组和rh-EPO D 组)MDA-MB-231细胞增殖的情况.用10 μmol·L-1p38MAPK抑制剂SB203580、ERK抑制剂U0126、JNK抑制剂SP600125和NF-κB 抑制剂PDTC预处理人乳腺癌 MDA-MB-231 细胞后,用MTT法检测经100、200、300和400 U·mL-1的rh-EPO(PDTC+EPO 组、SB203580+EPO 组、SP600125+EPO组和U0126+EPO组)诱导后细胞增殖的情况.结果 阴性对照组、rh-EPO A 组、rh-EPO B组、rh-EPO C 组和rh-EPO D 组 72 h PI值分别为:1.000 0±1.000 0、1.231 8±0.133 0、1.323 9±0.136 0、1.351 7±0.146 0和1.423 1±0.084 0;96 h PI值分别为:1.000 0±1.000 0、1.352 5±0.036 0、1.359 7±0.112 0、1.387 2±0.063 0和1.410 8±0.060 0.rh-EPO A 组、rh-EPO B组、rh-EPO C 组和rh-EPO D 组 72、96 h PI值与阴性对照组比较差异均有统计学意义(均P<0.05).PDTC+EPO 组、SB203580+EPO 组72、96 h PI值均较EPO组明显降低(均P<0.05),SP600125+EPO组、U0126+EPO组72、96 h PI值与EPO组比较差异均无统计学意义(均P>0.05).结论 rh-EPO可能是通过NF-κB、MAPK传导通路发挥效应,促进人乳腺癌MDA-MB-231细胞增殖. 相似文献