以CHO-K1细胞为研究对象,首先对贴壁细胞进行了悬浮驯化,之后比较了自配无血清培养基CHO-SFM、Sigma Ex-CELL CD CHO培养基和Gibco CD CHO培养基驯化悬浮细胞CHO-K1-S的培养效果。在相同实验条件下,统计细胞的增长率和存活率。结果表明...以CHO-K1细胞为研究对象,首先对贴壁细胞进行了悬浮驯化,之后比较了自配无血清培养基CHO-SFM、Sigma Ex-CELL CD CHO培养基和Gibco CD CHO培养基驯化悬浮细胞CHO-K1-S的培养效果。在相同实验条件下,统计细胞的增长率和存活率。结果表明,自配无血清培养基CHO-SFM优于Sigma CD-CHO和Gibco CD-CHO两种商业化培养基。展开更多
According to the urbanization extent of Beijing area, and with 1980 as a turning point, the duration from 1961 to 2000 is divided into two periods: one is defined as the slow urbanization period from 1961 to 1980, and...According to the urbanization extent of Beijing area, and with 1980 as a turning point, the duration from 1961 to 2000 is divided into two periods: one is defined as the slow urbanization period from 1961 to 1980, and other one as the fast urbanization period from 1981 to 2000. Based on the 40-year’s precipi-tation data of 14 standard weather stations in Beijing area, the effect of urbanization on precipitation distribution is studied. It is found that there has been a noticeable and systematic change of winter precipitation distribution pattern between these two periods in Beijing area: in the slow urbanization period, the precipitation in the southern part of Beijing is more than that in the northern part; but in the fast urbanization period, the precipitation distribution pattern is reverse, i.e. the precipitation in the southern part is less than that in the northern part; But in other seasons, the precipitation distribution pattern did not change remarkably in general. The possible cause resulting in the change of winter precipitation distribution pattern, might be that with urban area extension, the effects of "urban heat island" and "urban dry island" become more and more intensified, and increase hydrometeors evapo-ration below precipitable cloud, and then cause less precipitation received on the ground surface in the downtown and the southern part. It is also noteworthy to further research why the precipitation distri-bution pattern does not change systematically in other seasons except winter after intense urbaniza-tion in Beijing area.展开更多
文摘以CHO-K1细胞为研究对象,首先对贴壁细胞进行了悬浮驯化,之后比较了自配无血清培养基CHO-SFM、Sigma Ex-CELL CD CHO培养基和Gibco CD CHO培养基驯化悬浮细胞CHO-K1-S的培养效果。在相同实验条件下,统计细胞的增长率和存活率。结果表明,自配无血清培养基CHO-SFM优于Sigma CD-CHO和Gibco CD-CHO两种商业化培养基。
基金Supported by Major State Basic Research Development Program of Ministry of Science and Technology of China (Grant No. 2005CB422205)Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No. KZCZ2- YW-219)
文摘According to the urbanization extent of Beijing area, and with 1980 as a turning point, the duration from 1961 to 2000 is divided into two periods: one is defined as the slow urbanization period from 1961 to 1980, and other one as the fast urbanization period from 1981 to 2000. Based on the 40-year’s precipi-tation data of 14 standard weather stations in Beijing area, the effect of urbanization on precipitation distribution is studied. It is found that there has been a noticeable and systematic change of winter precipitation distribution pattern between these two periods in Beijing area: in the slow urbanization period, the precipitation in the southern part of Beijing is more than that in the northern part; but in the fast urbanization period, the precipitation distribution pattern is reverse, i.e. the precipitation in the southern part is less than that in the northern part; But in other seasons, the precipitation distribution pattern did not change remarkably in general. The possible cause resulting in the change of winter precipitation distribution pattern, might be that with urban area extension, the effects of "urban heat island" and "urban dry island" become more and more intensified, and increase hydrometeors evapo-ration below precipitable cloud, and then cause less precipitation received on the ground surface in the downtown and the southern part. It is also noteworthy to further research why the precipitation distri-bution pattern does not change systematically in other seasons except winter after intense urbaniza-tion in Beijing area.
