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91.
Transgenic mice overexpressing the 770-amino acid isoform of human Alzheimer amyloid precursor protein exhibit extracellular
β-amyloid deposits in brain regions including cerebral cortex and hippocampus, which are severely affected in Alzheimer’s
disease patients. Significant reduction in choline acetyltransferase (ChAT) activities has been observed in both cortical
and hippocampal brain regions in the transgenic mice at the age of 10 months compared with the age-matched non-transgenic
mice, but such changes have not been observed in any brain regions of the transgenic mice under the age of 5 months. These
results suggest that deposition of β-amyloid can induce changes in the brain cholinergic system of the transgenic mice. 相似文献
92.
采用人工生命的方法,定量模拟了不同条件下害虫对转基因植物抗性性的进化速度。结果显示只转入植物一个毒性基因常使害虫在短时间内产生抗性,若转3-4个不会产生交互抗性的毒性基因则可大大推迟到或阻止抗性的产生。 相似文献
93.
94.
将来自pBI121质粒的CaMV35S启动子片段插入到pBI121的CaMV35S启动子与GUS基因之间,构建了串联的CaMV35S启动子载体pLB38.通过三亲交配,将pBI121及pLB38分别转移到含pGv3850的农杆菌中,成为适合本研究的双元载体。以叶圆盘转化法将外源基因转入烟草,获得了2种转基因植株。经DNA分子杂交、NPTⅡ点分析、GUS荧光定性及定量分析,证明外源基因已整合进烟草基因组并获得表达。pLB38的GUS表达量为nBl121的3~4倍,这表明启动子数目的不同会直接影响其启动基因的表达水平。 相似文献
95.
刘厚凤 《山东师范大学学报(自然科学版)》1993,8(4):23-28
水资源紧缺是我国黄淮海农业发展的主要限制因素。在有限水资源条件下,如何合理灌溉,发挥最佳效益是亟待解决的问题。作者首次运用桑斯威特的气候学水分收支平衡理论,进行土壤水分平衡模拟。在此基础上定量计算农田水分盈亏状况,根据水分对作物产量的影响,提出水资源有限情况下的最优化灌溉方案。 相似文献
96.
97.
Neurofilament proteins in neurodegenerative diseases 总被引:3,自引:0,他引:3
Liu Q Xie F Siedlak SL Nunomura A Honda K Moreira PI Zhua X Smith MA Perry G 《Cellular and molecular life sciences : CMLS》2004,61(24):3057-3075
The function of neurofilaments, the major component in large myelinated neurons, is not well understood even though they were discovered as structures over 100 years ago. Recent studies have suggested that neuro-filaments are closely related to many neurodegenerative diseases, such as amyotrophic lateral sclerosis, Parkinson disease Alzheimer disease, and diabetes. Using in vitro assays, cultures and transgenic mice, these studies provided new insights into neurofilament function. The function of each subunit, the relationship of neurofilaments with other cytoskeletal elements and their clinical significance are topics of increasing attention.Received 22 June 2004; received after revision 4 August 2004; accepted 19 August 2004 相似文献
98.
GUOQionglin WANGYaping JIAWeizhang ZHUZuoyan 《科学通报(英文版)》2003,48(16):1764-1770
The transgenic carp were produced by micro-injection of CAgcGHc into the fertilized eggs. Observation of the thymus development between the transgenics and non- transgenic controls was carried out. The thymus of one-year- old transgenics F1 showed a great increase in both size and weight. The unilateral thymus of the transgenics weighed from 190 to 295 mg with average 218.6 mg, whereas the uni-lateral thymus of the controls weighed 20—81 mg with av-erage 42.5 mg; i.e. the thymus weight in the transgenics was 5.14 fold over that in the controls. The index of thymus/body weight in the transgenics was 2.97 fold over the controls. Light microscopy observation indicated that the thymus of the transgenics well developed with the thickened outer re-gion and compactly arranged thymocytes, while the thymus in the controls were degenerating with the thinned outer region, scattered thymocytes and groups of fatty cells. Fur-ther analysis with the electron microscopy revealed that pro-liferous cells in the transgenics were mainly small lympho-cytes and no pathological changes were found. The results confirmed that the 揂ll-fish?GH-transgene promotes thy-mus development and thymocyte proliferation, and retards thymus degeneration. The study has laid a foundation for further analysis of the immunobiological function in GH- transgenic carp. 相似文献
99.
Wong RW 《Cellular and molecular life sciences : CMLS》2003,60(1):113-118
Generation of genetically engineered mice with either gain-of-function or loss-of-function mutations is the most popular
technique for determining gene functions and the interrelationship between molecules in vivo. These models have provided a
wealth of information about the developmental and physiological roles of oncogenes and growth factors. To date, transgenic
techniques have been used extensively to study the functions of the epidermal growth factor (EGF) family. This review highlights
some of the major recent findings pertinent to the EGF receptor (EGFR) and its ligands with special reference to elucidating
how EGF and its related growth factors work together to regulate reproduction, growth and development. Finally, future investigations
on ligand-ligand communications, EGFR and its ligands in neural stem cell research, and the mechanisms of EGFR signaling and
trafficking in cells are also suggested.
Received 24 May 2002; received after revision 15 July 2002; accepted 16 July 2002 相似文献
100.
Ying Huang Kezhong Zhang Wenying Huang Daru Lu Ying Huang Zhanlu Ma Zhaorui Ren Xinfang Qiu Jinglun Xue Yitao Zeng Shuzhen Huang 《科学通报(英文版)》1998,43(15):1294-1298
The DNA of human factor IX (hF IX) gene vector pMC IX m, which had been proven to be able to express inin vitro and living cells, was introduced into 586 zygotes of Kunming Whlte Mice by positive pressure microinjection technique with
manual operation. The 499 survival embryos after microinjection were then transferred into pseudopregnant recipient mice and
216 F, pups were born. The analysis of PCR and Southern blot hybridization showed that, of the 216, 6 (2 females and 4 males)
were integrated with foreign DNA in their genornes, giving an integration frequency of 3% (6/216). Two F0 female transgenic mice could express hF IX protein in their milk and the content was over 100 ng/mL as measured with ELISA.
The biological activities of hF IV in the milk of two F0 mike were 44.67 % and 79.43 %, respectively. 相似文献