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1.
本研究采用氨基酸分析法结合DOE设计法优化并获得高表达抗PD-1单克隆抗体生产用基础和补料培养基。通过对市售多种基础和补料培养基进行筛选,获得细胞生长状况较优的基础培养基和抗体表达较高的补料培养基,利用氨基酸分析法检测较优基础培养基和补料培养基中氨基酸消耗情况,确定影响细胞生长和抗体表达的关键氨基酸种类,利用DOE分析软件设计分别在较优基础和补料培养基中添加不同浓度的氨基酸种类及浓度,根据细胞生长及抗体表达,优化得到抗PD-1单克隆抗体的基础和补料培养基组合。最终优化后基础培养基配方为:Hycell CHO培养基中添加1.04 mmol/L L-天冬酰胺和0.76 mmol/L L-谷氨酰胺。最终优化后补料培养基配方为:OPM CHOCD Feed1补料培养基中添加38.7 mmol/L L-组氨酸,75.0 mmol/L L-酪氨酸,64.0 mmol/L L-丝氨酸,49.2 mmol/L L-谷氨酰胺和18.7 mmol/L L-半胱氨酸。经过3 L反应器培养验证,优化后的培养基比未优化时,最大活细胞密度(PVCD)提高了62.7%,抗PD-1单克隆抗体表达量提高了71.5%,且活性无明显差异。  相似文献   

2.
The anion sensing ability of compound 1 based on a novel 2,4-dinitrophenylhydrazone derivative was studied through "naked-eye" experiment, UV-Vis spectral titration, and (1)H NMR titration. Sensor 1 was synthesized through a simple method with high yield. The solution of host 1 turned deep purple from light purple in the presence of the strong basic anions and turned yellow upon addition of the weak basic anions, respectively. The results could be explained on the basis of transfer of the tautomeric equilibrium of sensor 1 induced by anions with different basicity.  相似文献   

3.
A series of thiophene PLK1 inhibitors was optimized for increased solubility and reduced protein binding through the appendage of basic amine functionality. Interesting selectivity between PLK1 and PLK3 was also obtained through these modifications.  相似文献   

4.
Mast cells play a central role in inflammatory and allergic reactions by releasing inflammatory mediators through two main pathways, immunoglobulin E-dependent and -independent activation. In the latter, mast cells are activated by a diverse range of basic molecules, including peptides and amines such as substance P, neuropeptide Y, and compound 48/80. These secretagogues are thought to activate the G proteins in mast cells through a receptor-independent mechanism. Here, we report that the basic molecules activate G proteins through the Mas-related gene (Mrg) receptors on mast cells, leading to mast cell degranulation. We suggest that one of the Mrg receptors, MrgX2, has an important role in regulating inflammatory responses to non-immunological activation of human mast cells.  相似文献   

5.
Myelin basic protein isolated by a single step with the cationic detergent cethyltrimethylammonium bromide in a lipid-bound form is able to induce structural transition of lysophosphatydilcholine micelles into multi-laminar vesicles. This finding, observed through electron microscopy, is discussed in the light of the assumed ability of the basic protein to organize myelin lipids.  相似文献   

6.
For nearly a century we have understood that life works through genes, and so have had an elegant theory for general evolution. But this did not explain the kinds of traits that characterize organisms, nor how genes produce them. Advances in recent decades have opened the way for an understanding of the phenogenetic logic or relational principles of life, by which a few basic characteristics of genomes produce biological phenotypes through some basic developmental processes. This logic provides a general explanation of the nature and source of organismal design, and a powerful programme for research.  相似文献   

7.
8.
心理测评是一种应用范围很广的心理学研究的方法,为广大基层部队和医院培养出高水平的心理测评人才对于实现强军目标具有非常重要的意义。我科室通过对军校学员开展心理测评教学的多年经验,总结出一套适应于为基层部队培养出能够实际应用型心理测评人才的教学方案,通过基础理论课、实践操作课以及讨论课等一系列教学课程,使学员不仅能够掌握基础理论,同时还可以快速的将理论应用于实践操作中,大大提高了教学的内容和质量。  相似文献   

9.
The chemical theory of staining is discussed in the light of recent discoveries respecting the mechanism of the reaction of basic dyes with substances of an acid character. It is pointed out that staining may result through the formation of addition products as well as through the formation of dye salts.  相似文献   

10.
艾滋病毒的 Tat蛋白碱性结构域的 1 3个氨基酸的多肽能自主穿越细胞膜并将与之融合表达的其他蛋白带入细胞 .为探讨融合表达的蛋白是否可保持原有的主要生物学功能 ,将 Bcl- Xs蛋白与 Tat碱性结构域在大肠杆菌中融合表达 ,重组蛋白 Tat- Bcl- Xs与 CHO、CNE、Hela和 772 1细胞共温育一段时间后 ,细胞均可见明显生长抑制 ,同时细胞变圆、变小、细胞核收缩 ,并有染色体凝聚、边缘化 ,或细胞核分裂为小核的现象 ,同时出现梯状 DNA,为较典型的细胞程序性死亡 ( PCD)表现 .同时发现放线菌素 D、雷公藤内脂醇与 Tat- Bcl- Xs在诱导细胞 PCD时存在交互作用 .提示Tat- Bcl- Xs蛋白可自主进入细胞内 ,并保持了 Bcl- Xs蛋白的 PCD诱导作用 ,初步证实了利用 Tat碱性结构域进行药物设计的可行性 ,同时也提示 Tat- Bcl- Xs蛋白可能可作为多种药物联合治疗中的一员而在抗肿瘤治疗中发挥作用  相似文献   

11.
The chemical theory of staining is discussed in the light of recent discoveries respecting the mechanism of the reaction of basic dyes with substances of an acid character. It is pointed out that staining may result through the formation of addition products as well as through the formation of dye salts.  相似文献   

12.
The pH dependence and kinetics parameters of renin-angiotensinogen reactions were determined using wild-type and S84G mutant human renins and wild-type and H13Y mutant sheep angiotensinogens. It is explained in this report that (i) renin catalyzes acidic and basic reactions of which the optimum pHs are 5.5 and 7.5-8.2 respectively, both of which produce angiotensin I; (ii) Ser84 specific to human renin accelerates the acidic reaction by 75-110% through elevation of V(max), and shifts the optimum pH of the basic reaction from 7.5 to 8.0-8.2; and (iii) His13 specific to sheep angiotensinogen accelerates the acidic and basic reactions by 25-42% through reduction of K(m). It is concluded from these results that the coexistence of Ser84 in renin and His13 in angiotensinogen brings a pH profile of two separate peaks at pHs 5.5 and 8.2 to the reaction of human renin and sheep angiotensinogen.  相似文献   

13.
14.
SUMMARY: RECSIM takes a general genealogy and simulates the transmission of chromosomes through that genealogy. INDSTATS extracts some basic statistics from the output of RECSIM.  相似文献   

15.
We have confirmed the hypothesis that a mitotoxin resulting from the conjugation of basic fibroblast growth factor and saporin exerts its cytotoxic effect through specific interaction with the basic fibroblast growth factor (FGF) receptor. Accordingly, the mitotoxin stimulates tyrosine phosphorylation of the 90 kD substrate that characterizes the initial cellular response to basic FGF. Cross-linking experiments show that radio-labeled basic fibroblast growth factor-saporin (FGF-SAP) binds to the receptor. Suramin, an inhibitor of growth factor receptor binding, inhibits the cytotoxicity of basic FGF-SAP. In a study of 4 different cell types, there is a decrease in the ED50 of the mitotoxin as the receptor number per cell increases. We have verified the cytotoxicity of the mitotoxin in 3 different assay systems. As expected, it is effective in the inhibition of protein synthesis and DNA synthesis, as well as of cell count. Binding of basic FGF-SAP which will result in cytotoxicity occurs very rapidly; 5 minutes of incubation of 10 nM basic FGF-SAP with cells results in 80% inhibition of cell count. The in vitro data indicate that the basic FGF-SAP is a receptor specific and potent suicide antagonist of basic FGF. Its potential as an anti-FGF for therapeutic and research uses in vivo is discussed.  相似文献   

16.
Touré YT 《Parassitologia》1999,41(1-3):507-509
Malaria control has had little success in Africa despite the achievements in malaria research. It is time to put more emphasis on sustainable control measures through local commitment to diagnose and treat malaria in order to prevent illness and death. This goal can be best achieved through basic health care centers, schools and safe water supplies to rural areas. Complementary actions through research and international support will be strongly needed.  相似文献   

17.
V. C. Wright 《CMAJ》1982,126(9):1035
In 1917 Einstein theorized tha through an atomic process a unique kind of electromagnetic radiation could be produced by stimulated emission. When such radiation is in the optical or infrared spectrum it is termed laser (light amplification by stimulated emission of radiation) light. A laser, a high-intensity light source, emits a nearly parallel electromagnetic beam of energy at a given wavelength that can be captured by a lens and concentrated in the focal spot. The wavelength determines how the laser will be used. The carbon dioxide laser is now successfully employed for some surgical procedures in gynecology, otorhinolaryngology, neurosurgery, and plastic and general surgery. The CO2 laser beam is directed through the viewing system of an operating microscope or through a hand-held laser component. Its basic action in tissue is thermal vaporization; it causes minimal damage to adjacent tissues. Surgeons require special training in the basic methods and techniques of laser surgery, as well as in the safety standards that must be observed.  相似文献   

18.
Garaeva  A. Ya.  Sidorova  A. E.  Levashova  N. T.  Tverdislov  V. A. 《Biophysics》2020,65(3):522-531
Biophysics - This review considers the basic models of mutation processes that occur during selection and drift. A basically new model was developed to describe the mutation flow through a...  相似文献   

19.
A basic protein designated TP2 has been isolated from rat testis elongated spermatids. This new protein contains basic and acidic amino acids in relative amounts similar to those in histone F2al but is unusually rich in serine and proline. Techniques which were developed for preparing relatively homogeneous populations of spermatid nuclei were used to demonstrate that TP2 is most abundant and most actively synthesized in spermatids representing steps 12 through 15 of spermiogenesis.  相似文献   

20.
Abstract

Amyloid detection is very precise at this time, because several methods are available to the pathologist. Awareness of potential nonspecific staining, possible pitfalls and methods for improving the detection process are basic to enhancing the staining of amyloid and interpreting this staining. The role of the pathologist has progressed through history from the basic detection of amyloid as a substance to immunophenotypical classification of the particular amyloid present.  相似文献   

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