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1.
研究了不同葡萄糖、谷氨酰胺浓度下JAL1细胞的生长、糖耗、乳酸及氨的生成、单抗合成等代谢过程及该株细胞的基本代谢规律,同时对该株细胞生长和单抗生产的动力学方面进行了研究,在细胞培养箱中,采用方瓶批量培养杂交瘤细胞,培养条件为pH7.0-7.5,温度37℃,5%CO2。实验表明,在不同浓度葡萄糖、谷氨酰胺的培养液中,细胞的活性细胞密度、总细胞密度、细胞活性上均有不同,相应地,对细胞的最大比生长速率、葡萄糖最大比消耗速率、乳酸最大比生成速率以及单抗最大比合成速率也有不同程度的影响。实验结果还表明,该株细胞的单抗分泌是属于负生长耦联型的。  相似文献   

2.
通过WuT3杂交瘤细胞的流加培养,当葡萄糖浓度分别控制在0.2、0.5、1.0和1.5g/L时,葡萄糖的平均比消耗速率分别为1.14×10-11、1.47×10-11、1.78×10-11和2.24×10-11g/(cell.h),乳酸的平均比生成速率分别为6.0×10-12、8.3×10-12、11.6×10-12和16.6×10-12g/(cell.h).葡萄糖转化成乳酸的比例分别52%、57%、64%和74%.结果表明,在WuT3细胞的流加培养中,当葡萄糖浓度在0.2~1.5g/L时,葡萄糖浓度越低,葡萄糖的比消耗速率和乳酸的比生成速率越低,葡萄糖转化成乳酸的比例越低,从而提高了葡萄糖的有效利用率,减少副产物的生成.  相似文献   

3.
杂交瘤细胞流加培养中葡萄糖浓度的控制   总被引:2,自引:2,他引:0  
通过 Wu T3杂交瘤细胞的流加培养 ,当葡萄糖浓度分别控制在 0 .2、0 .5、1 .0和 1 .5g/L时 ,葡萄糖的平均比消耗速率为 1 .1 4× 1 0 -11、1 .47× 1 0 -11、1 .78× 1 0 -11和 2 .2 4× 1 0 -11g/( cell· h) ,乳酸的平均比生成速率为 6.0× 1 0 -12 、8.3× 1 0 -12 、1 1 .6× 1 0 -12 和 1 6.6× 1 0 -12 g/( cell· h)。葡萄糖转化成乳酸的比例为 52 %、57%、64%和 74%。结果表明 ,在 Wu T3细胞的流加培养中 ,当葡萄糖浓度在 0 .2~ 1 .5g/L时 ,葡萄糖浓度越低 ,葡萄糖的比消耗速率和乳酸的比生成速率越低 ,葡萄糖转化成乳酸的比例越低 ,从而提高了葡萄糖的有效利用率 ,减少副产物的生成。  相似文献   

4.
考察了葡萄糖或谷氨酰胺限制的批培养中杂交瘤细胞的生长、代谢和单抗生成。葡萄糖或谷氨酰胺限制时最大活细胞密度基本相同,为(1.0±0.1)×106cells/mL。葡萄糖限制时,乳酸生成减少,YLac/Glc降低,YCell/Glc增加,提示葡萄糖更多地参与三羧酸循环。谷氨酰胺限制时,氨和丙氨酸生成减少,YAmm/Gln增加,YAla/Gln减小,提示谷氨酰胺的能量利用率提高。谷氨酰胺缺失时异亮氨酸、亮氨酸、胱氨酸、缬氨酸、色氨酸、组氨酸等替代谷氨酰胺,维持细胞生长和单抗合成,产物是甘氨酸和天冬氨酸。单抗生成与细胞生长关联,并且细胞停止生长后单抗仍生成。细胞死亡阶段的qMAb约是生长阶段的一半。葡萄糖和谷氨酰胺共限制下细胞对单抗的生产能力比葡萄糖和谷氨酰胺单独限制时小。  相似文献   

5.
采用流加培养方式,实现了杂交瘤细胞在营养物富裕、葡萄糖限制和谷氨酰胺限制3种条件下的拟稳态培养。代谢动力学分析表明:葡萄糖限制时,葡萄糖比消耗速率(qGluc)降低到1.1×10-9mmol/(cell·d),相比营养物富裕时降低了40%以上;乳酸生成量降到最低。谷氨酰胺限制时,谷氨酰胺的最小比消耗速率(qGln)约为0.28×10-9mmol/(cell·d),相比营养物富裕时降低了56%以上;氨的比生成速率降低到0.23×10-9mmol/(cell·d),营养物富裕时为0.93×10-9mmol/(cell·d);丙氨酸的生成降到最低。3种拟稳态下单抗的比生成速率都在29×10-9~37×10-9mg/(cell·d)。本文的流加培养设计方法为快速认识细胞的代谢规律,设计相应的培养基和调控策略,实现细胞高密度和产物高浓度的培养过程提供了指导。  相似文献   

6.
氨对重组中国仓鼠卵巢(CHO)细胞的生长具有明显的抑制作用,并遵循二级抑制模型,抑制常数Ka为41.5(mmol/L)^2,即当氨浓度为6.45mmol/L时,细胞的比生长速率下降到最大比生长速率的50%,在重组CHO细胞的批培养过程中,细胞密度和红细胞生成素浓度随着起始氨浓度的提高而下降,但存在一最适的氨浓度,在此浓度下,单位重组CHO细胞的EPO比生成速率最大。  相似文献   

7.
研究了无血清培养中的代谢副产物丙氨酸对杂交瘤细胞生长代谢的影响。丙氨酸浓度在0-8.9mmol/L范围时,丙氨酸对细胞生长影响不大,对单抗的生成没有直接影响,但对细胞代谢有较大的影响,随着丙氨酸浓度的提高,葡萄糖的消耗增加;同时,乳酸的生成增加,而丙氨酸和氨的生成减小。  相似文献   

8.
观察了分泌抗IBDV单抗杂交瘤细胞在改良型5L Celligen细胞反应器中采用半连续培养方式的生长和代谢情况,研究了在该工艺过程中的葡萄糖消耗、单抗的生成、乳酸和氨的产生.同时为培养方案和控制策略进一步的改良确定方向.  相似文献   

9.
在生物反应器的批培养过程中考察了葡萄糖及谷氨酰胺浓度对杂交瘤细胞生长及代谢的影响。当葡萄糖浓度降至1~4mmol/L,谷氨酰胺浓度降至0.4~2mmol/L时,细胞生长并未受到明显影响,但细胞代谢途径发生转换,乳酸及氨的生成显著减少。葡萄糖和谷氨酰胺浓度的比例对杂交瘤细胞的生长及代谢也有影响,葡萄糖相对较多时,其细胞得率小,乳酸得率大;而当谷氨酰胺相对较多时,其细胞得率小,氨得率大。实验结果表明谷氨酰胺与葡萄糖的能量代谢在某种程度上可进行相互补充。  相似文献   

10.
 在搅拌式生物反应器中,应用批培养、流加培养和灌流培养3种方法对CHO-k1细胞进行了培养.3种方法最大活细胞密度分别达到了2.0×106,2.7×106和9.6×106mL-1.对培养过程中葡萄糖和氨基酸及代谢产物氨和乳酸的动态变化进行了检测和分析.结果表明,CHO细胞对葡萄糖和谷氨酰胺的摄取以及氨和乳酸的产生与培养液中葡萄糖和谷氨酰胺的浓度正相关,培养过程中控制葡萄糖和谷氨酰胺的加入量能够明显降低氨和乳酸的产生,提高代谢效率,增加细胞产量.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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