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991.
水产养殖业是动物性食物生产增长速度最快的领域,采用现代生物技术以满足人们对水产养殖产品的数量和质量增长的需求日益迫切.在水产养殖动物中已经发展了显微注射、电穿孔、基因枪轰击、精子介导、直接混合、脂质体介导、电穿孔精子载体、生殖腺直接注射等转基因方法,各种方法各有优缺点,针对不同的动物和不同的目的可以选择其中一种方法或几种方法结合使用.鱼类的转基因技术和应用发展较为成熟,但在虾类和贝类中还不稳定,目前主要集中在发展有效的转基因技术上:影响转基因技术在水产动物中的因素除技术的稳定性和基因的整合率外,转基因动物的生态和遗传风险也需要高度关注. 相似文献
992.
993.
Genotype-imputation methods provide an essential technique for high-resolution genome-wide association (GWA) studies with millions of single-nucleotide polymorphisms. For optimal design and interpretation of imputation-based GWA studies, it is important to understand the connection between imputation error and power to detect associations at imputed markers. Here, using a 2 × 3 chi-square test, we describe a relationship between genotype-imputation error rates and the sample-size inflation required for achieving statistical power at an imputed marker equal to that obtained if genotypes at the marker were known with certainty. Surprisingly, typical imputation error rates (∼2%–6%) lead to a large increase in the required sample size (∼10%–60%), and in some African populations whose genotypes are particularly difficult to impute, the required sample-size increase is as high as ∼30%–150%. In most populations, each 1% increase in imputation error leads to an increase of ∼5%–13% in the sample size required for maintaining power. These results imply that in GWA sample-size calculations investigators will need to account for a potentially considerable loss of power from even low levels of imputation error and that development of additional genomic resources that decrease imputation error will translate into substantial reduction in the sample sizes needed for imputation-based detection of the variants that underlie complex human diseases. 相似文献
994.
ZFP245 is a cold- and drought-responsive gene that encodes a zinc finger protein in rice. The ZFP245 protein localizes in the nucleus and exhibits trans-activation activity. Transgenic rice plants overexpressing ZFP245 were generated and found to display high tolerance to cold and drought stresses. The transgenic plants did not exhibit growth retardation, but showed growth sensitivity against exogenous abscisic acid, increased free proline levels and elevated expression of rice pyrroline-5-carboxylatesynthetase and proline transporter genes under stress conditions. Overproduction of ZFP245 enhanced the activities of reactive oxygen species-scavenging enzymes under stress conditions and increased the tolerance of rice seedlings to oxidative stress. Our data suggest that ZFP245 may contribute to the tolerance of rice plants to cold and drought stresses by regulating proline levels and reactive oxygen species-scavenging activities, and therefore may be useful for developing transgenic crops with enhanced tolerance to abiotic stress. 相似文献
995.
996.
Wei-Hsin Chen Ching-Liang Hsieh Chun-Ping Huang Tzu-Jou Lin Jason TC Tzen Tin-Yun Ho Yi-Wen Lin 《Journal of biomedical science》2011,18(1):82
Background
Peripheral tissue inflammation initiates hyperalgesia accompanied by tissue acidosis, nociceptor activation, and inflammation mediators. Recent studies have suggested a significantly increased expression of acid-sensing ion channel 3 (ASIC3) in both carrageenan- and complete Freund's adjuvant (CFA)-induced inflammation. This study tested the hypothesis that acupuncture is curative for mechanical hyperalgesia induced by peripheral inflammation. 相似文献997.
Haiwei Pi Yi-Chun Huang I-Chun Chen Chung-De Lin Hsiao-Fong Yeh Li-Mei Pai 《Journal of biomedical science》2011,18(1):42
Background
The conserved Notch signaling pathway regulates cell fate decisions and maintains stem cells in multicellular organisms. Up-regulation of Notch signaling is observed in several types of cancer and is causally involved in proliferation and survival of cancer cells. Thus, it is of great interest to look for anti-Notch reagents for therapeutic purposes. In model animal Drosophila, Notch signaling restricts selection of sensory organ precursors (SOPs) during external sensory (ES) organ development. To look for novel genes that can suppress Notch signaling, we performed a gain-of-function modifier screen to look for genes that enhance the phenotype of ectopic ES organs induced by overexpression of phyllopod, a gene required for SOP specification. 相似文献998.
目的:探讨Toll样受体4(TLR4)在哮喘状态下气道平滑肌细胞(ASMCs)增殖、凋亡中的作用.方法:建立哮喘大鼠模型,分离、培养哮喘大鼠气道平滑肌细胞,应用小分子RNA干扰技术、脂质体转染法进行小分子RNA-TLR4的转染、MTT,法检测细胞增殖、TUNNEL法检测细胞凋亡情况、逆转录聚合酶链式反应(RT-PCR)... 相似文献
999.
Focal adhesion assembly and disassembly are essential for cell migration and cancer invasion, but the detailed molecular mechanisms regulating these processes remain to be elucidated. Phosphatidylinositol phosphate kinase type Iγ (PIPKIγ) binds talin and is required for focal adhesion formation in EGF-stimulated cells, but its role in regulating focal adhesion dynamics and cancer invasion is poorly understood. We show here that overexpression of PIPKIγ promoted focal adhesion formation, whereas cells expressing either PIPKIγK188,200R or PIPKIγD316K, two kinase-dead mutants, had much fewer focal adhesions than those expressing WT PIPKIγ in CHO-K1 cells and HCT116 colon cancer cells. Furthermore, overexpression of PIPKIγ, but not PIPKIγK188,200R, resulted in an increase in both focal adhesion assembly and disassembly rates. Depletion of PIPKIγ by using shRNA strongly inhibited formation of focal adhesions in HCT116 cells. Overexpression of PIPKIγK188,200R or depletion of PIPKIγ reduced the strength of HCT116 cell adhesion to fibronection and inhibited the invasive capacities of HCT116 cells. PIPKIγ depletion reduced PIP2 levels to ∼40% of control and PIP3 to undetectable levels, and inhibited vinculin localizing to focal adhesions. Taken together, PIPKIγ positively regulates focal adhesion dynamics and cancer invasion, most probably through PIP2-mediated vinculin activation. 相似文献
1000.
Fairfield H Gilbert GJ Barter M Corrigan RR Curtain M Ding Y D'Ascenzo M Gerhardt DJ He C Huang W Richmond T Rowe L Probst FJ Bergstrom DE Murray SA Bult C Richardson J Kile BT Gut I Hager J Sigurdsson S Mauceli E Di Palma F Lindblad-Toh K Cunningham ML Cox TC Justice MJ Spector MS Lowe SW Albert T Donahue LR Jeddeloh J Shendure J Reinholdt LG 《Genome biology》2011,12(9):R86-12
We report the development and optimization of reagents for in-solution, hybridization-based capture of the mouse exome. By validating this approach in a multiple inbred strains and in novel mutant strains, we show that whole exome sequencing is a robust approach for discovery of putative mutations, irrespective of strain background. We found strong candidate mutations for the majority of mutant exomes sequenced, including new models of orofacial clefting, urogenital dysmorphology, kyphosis and autoimmune hepatitis. 相似文献