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141.
INTRODUCTION Because of its low molecular weight and ability to fluoresce independently (George, 1997), the new molecular tag, green fluorescent protein (GFP), has become more and more popular after Prasher et al.(1992) cloned its cDNA in 1992. There are many reports describing the co-expression of GFP and a specific antibody or cytokine gene, with the fusion protein expressing the fluorescent activity and bio-logical activity of the complement protein (Haraguchi et al., 1999; Mclean…  相似文献   
142.
发挥电大优势为社区教育提供社会化服务   总被引:5,自引:2,他引:5  
社区教育是终身教育的一部分。在我国构筑终身教育体系,创建学习化社会,应立足于社区。电大以自己的系统优势、设施优势和教育资源优势为社区教育提供全方位的支持服务,完全有能力参与和推动社区教育。在实现教育的大众化普及化,促进全民终身学习的同时电大又可以得到自身的发展。  相似文献   
143.
本文从高等学校创新体系这一概念的提出入手,较为系统地对当前我国高教理论界颇具代表性的高等学校创新体系的表述进行了辨析,在此基础上,提出了新的表述并对其内涵进行了全新的阐述.  相似文献   
144.
试论大学生思想政治教育方法的创新   总被引:2,自引:0,他引:2  
新形势下大学生思想政治教育方法的创新必须做到“四个结合”,即政治教育与成才教育相结合,理性教育与感性教育相结合,主导教育与自我教育相结合,解决思想问题与解决实际问题相结合,并采取灵活多样的工作方法。  相似文献   
145.
张璐 《教育学报》2002,(5):12-14
21世纪应该是个人文教育空前发展的时代 ,社会科学也越来越凸现了它的重要性。文章通过比较世界各国的课程教学情况 ,在课程内容方面论述了 2 1世纪的社会科学课程。  相似文献   
146.
李煜的前期词与其性格是统一的,它们都受唐五代词风的影响,同时又是南唐社会的一个缩影,这些因素综合在一起,决定了南唐必然亡国的命运。本文就是从这个角度讨论了李煜前期词与其亡国的关系。  相似文献   
147.
Chang  Xin  Zhang  Chengyu  Gao  Lan  Liu  Xiao  You  Shengping  Qi  Wei  Wang  Kang  Guo  Xin  Su  Rongxin  Lu  Han  He  Zhimin 《天津大学学报(英文版)》2019,25(5):488-496
2,5-Furandicarboxylic acid(FDCA) is a potential biorenewable chemical for applications including plastics, polyamides, drugs, etc. The selective biosynthesis of FDCA from 5-hydroxymethylfurfural(HMF) by a specific enzyme poses a great challenge. In this study, we reported an efficient strategy to produce FDCA from HMF by the tandem biocatalysis of laccase(Cot A-TJ102@UIO-66-NH_2) and Novozym 435. For the first step, a nanoparticle metal–organic framework was synthesized as a carrier to immobilize Cot A-TJ102@UIO-66-NH_2, which was assigned for the production of 5-formyl-2-furancarboxylic acid(FFCA) and featured an enzyme loading of 255.54 mg/g, specific activity of 135.90 U/mg, and solid loading ratio of 99.65%. Under optimal conditions, an ideal FFCA yield of 98.5% was achieved, and the Cot A-TJ102@UIO-66-NH_2 presented a high recycling capacity after 10 cycles. For the second step, Novozym 435 was applied for the further conversion of FFCA into FDCA, presenting a high FDCA yield of 95.5% under the optimized conditions. Novozym 435 also exhibited a high recyclability after eight cycles. As a result, the tandem biocatalysis strategy provided a 94.2% FDCA yield from HMF, indicating its excellence as a method for FDCA production.  相似文献   
148.
Objective: We aim to describe the environment iodine concentration in salt, water and soil along Zhejiang Province coast in the China foreland. It will be helpful for us to judge whether this area is insufficient in iodine and universal iodized salt is necessary or not. Methods: We collected iodized salt samples, drinking water samples (tap water in the towns, and well water or spring water in the villages), water samples from different sources (ditches, lakes, rivers) and soil samples through random sampling in June, 2005. Salt, water and soil iodine was detected by arsenic-cerium redox method. Statistical analysis was expressed as mean±SEMby Windows SPSS 13.0. Results: (1) The iodine concentration in salt was 27.9±4.33 mg/kg (n=108). (2) Seventy-five water samples were collected. The water iodine value was 0.6~84.8 μg/L (mean of 11.66 μg/L). The watershed along the Qiantang River has significantly higher iodine content than the water in Lin'an in mountain area (P<0.01). The iodine content and mean iodine content of tap water, well or spring water and natural water sources were 4.30±2.43 μg/L (n=34), 23.59±27.74 μg/L (n=19)and 12.72±10.72 μg/L (n=22) respectively. This indicated that among environmental water sources, the ditch iodine content was the highest with river water iodine being the lowest (P<0.01). (3) Soil iodine value was 0.11~2.93 mg/kg (mean of 1.32 mg/kg).Though there was no statistical difference of soil iodine in different districts (P=0.131), soil iodine content correlated positively with water iodine content. Conclusion: Iodine concentration in salt accords with national policy of adding iodine in salt. Foreland has more iodine in water than mountain area. The data reflected that water and soil iodine in foreland area was not high, which suggests universal iodized salt should be necessary. Environment iodine has relatively close association with pollution.  相似文献   
149.
在不考虑月经周期的情况下连续灌喂氯地酚5天,每天50mg,第8天肌注hCG2000IU,对猕猴具有一定的卵泡超数发育作用,最多可使双侧卵巢共24个卵泡发育,最大卵泡直径5—6mm,但不同个体反应变化较大。FSH hCG超排方案(考虑或不考虑月经周期,连续肌注FSH6天,共80—90IU,第8天肌注hCG2500IU)比氯地酚效果较好,最多可使双侧卵巢共28个卵泡发育,卵泡最大直径10mm,另外在1只猕猴观察到5个卵泡破裂将卵排出。电刺激采得之猕猴精子经洗涤后与用以上两种超排方案以卵泡吸得之卵子一同输入兔输卵管进行受精,获得2个原核期受精卵和1个桑椹胚。  相似文献   
150.
This study presents the building of an instrument to measure personal conceptions of intelligence based upon Dweck research, and some exploratory evidence. The instrument is directed to adolescents, has got more items than the original one and incorporates new aspects, such as the importance of effort and ability in relation with personal conceptions of intelligence. The results of a factor analysis evidenced the existence of two distinct factors — a static and a dynamic one — that explain together 31.7% of the total variance. The internal consistency of the scales evidenced alpha coefficients between .74 and .80. The results of a test-retest reliability study (with a month interval) proved to be better for the static scale than to the the dynamic one, as well as the results of an external validity study (correlations with grade point average). Some differential exploratory studies showed differences in personal conceptions of intelligence related to school grades (5th to 11th): the scores increased from the 5th to the 11th grade, showing that older students were less “static” (more “dynamic”), and also related to the socio-economic status (high vs. low): the higher SES subjects appeared less “static” (more “dynamic”) than the lower SES subjects.  相似文献   
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