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51.
Xu HP Zeng H Zhang DX Jia XL Luo CL Fang MX Nie QH Zhang XQ 《Genetics and molecular research : GMR》2011,10(4):2279-2289
We looked for variations that could be associated with chicken egg number at 300 days of age (EN300) in seven genes of the hypothalamic-pituitary-gonadal axis, including gonadotrophin-releasing hormone-I (GnRH-I), GnRH receptor (GnRHR), neuropeptide Y (NPY), dopamine D2 receptor (DRD2), vasoactive intestinal polypeptide (VIP), VIP receptor-1 (VIPR-1), prolactin (PRL), and the QTL region between 87 and 105 cM of the Z chromosome. Ten mutations in the seven genes were chosen to do marker-trait association analyses in a population comprising 1310 chickens, which were obtained from a company located in Guangdong Province of China. The C1704887T of VIPR-1 was found to have a highly significant association with EN300. The T5841629C of DRD2 and the C1715301T of VIPR-1 were significantly associated with EN300. A highly significant association was also found between the C1704887T-C1715301T haplotypes of VIPR-1 and EN300. H1H3 had the highest EN300. Four PCR-RFLP variations in the candidate QTL region were selected to investigate their genetic effects on EN300. The haplotypes of T32742468C-G32742603A in this region showed a highly significant association with EN300. Bioinformatics analyses showed that both T32742468C and G32742603A were located in intron 1 of the SH3-domain GRB2-like 2 (SH3GL2) gene. We conclude that five SNPs, including C1704887T and C1715301T of VIPR-1, T5841629C of DRD2, and T32742468C and G32742603A of SH3GL2, would be useful as markers for breeding to increase chicken EN300. 相似文献
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The Tibetan Plateau is an essential area to study the potential feedback effects of soils to climate change due to the rapid rise in its air temperature in the past several decades and the large amounts of soil organic carbon (SOC) stocks, particularly in the permafrost. Yet it is one of the most under-investigated regions in soil respiration (Rs) studies. Here, Rs rates were measured at 42 sites in alpine grasslands (including alpine steppes and meadows) along a transect across the Tibetan Plateau during the peak growing season of 2006 and 2007 in order to test whether: (1) belowground biomass (BGB) is most closely related to spatial variation in Rs due to high root biomass density, and (2) soil temperature significantly influences spatial pattern of Rs owing to metabolic limitation from the low temperature in cold, high-altitude ecosystems. The average daily mean Rs of the alpine grasslands at peak growing season was 3.92 μmol CO(2) m(-2) s(-1), ranging from 0.39 to 12.88 μmol CO(2) m(-2) s(-1), with average daily mean Rs of 2.01 and 5.49 μmol CO(2) m(-2) s(-1) for steppes and meadows, respectively. By regression tree analysis, BGB, aboveground biomass (AGB), SOC, soil moisture (SM), and vegetation type were selected out of 15 variables examined, as the factors influencing large-scale variation in Rs. With a structural equation modelling approach, we found only BGB and SM had direct effects on Rs, while other factors indirectly affecting Rs through BGB or SM. Most (80%) of the variation in Rs could be attributed to the difference in BGB among sites. BGB and SM together accounted for the majority (82%) of spatial patterns of Rs. Our results only support the first hypothesis, suggesting that models incorporating BGB and SM can improve Rs estimation at regional scale. 相似文献
54.
植物钙/钙调素介导的信号转导系统 总被引:1,自引:0,他引:1
钙离子(Ca2+)是一种重要的第二信使, 参与调节植物的生长发育和对环境的适应。钙调素(CaM)和类钙调蛋白(CML)是一类最主要的Ca2+感受器, 虽然其自身没有催化活性, 但可通过调节下游靶蛋白的活性, 进而调控细胞的各种生理活动。该文总结了植物体内CaM结合蛋白(CBP)的生理功能、鉴定方法和调控机理, 以及CaM介导的信号转导途径, 包括蛋白磷酸化与去磷酸化、基因转录、离子运输、活性氧代谢、激素和磷脂信号等, 并对今后的研究方向进行了展望。 相似文献
55.
盐度和温度对北美海蓬子在厦门海区引种以及生长特性的影响 总被引:2,自引:0,他引:2
研究了厦门海区盐度和温度对北美海蓬子(Salicornia bigelovii)种子萌发和幼苗生长的影响。结果显示,海蓬子种子对温度变化反应非常敏感,在15°C时发芽率最高(94%),但萌发指数最低,而在20°C时萌发指数最大;在盐度5g·L^-1时种子具有最高的发芽率和萌发指数,在盐度50g·L^-1时仍有13.3%的发芽率,并且各种盐度处理下逐日萌发指数均能在2天内达到最大。盐度10-20g·L^-1最适宜幼苗生长,高盐(〉30g·L^-1)具有一定的抑制作用,主要表现为生长缓慢,含水量和根系活力下降,并且根的盐敏感程度大于茎。在不同盐度处理下,北美海蓬子适应一种新的耐盐机制,在无盐(0g·L^-1)和高盐(40g·L^-1)胁迫下,过氧化氢酶(catalase,CAT)和过氧化物酶(peroxide,POD)这2种酶蛋白对盐离子效应敏感,起主要的抗氧化作用;相反,生长在适宜盐度范围(10-30g·L^-1)内,超氧化物歧化酶(superoxide dismutase,SOD)维持较高活性。研究结果表明,北美海蓬子适宜在沿海滩涂环境条件下生长,有望作为一种抗盐耐海水蔬菜加以开发和利用,并进一步在污染海水净化修复中发挥可能的生态功能。 相似文献
56.
Zack Frehlick Harvey Lui David I. McLean Shuo Tang Haishan Zeng 《Journal of biophotonics》2013,6(4):305-309
We present a multimodal in vivo skin imaging instrument that is capable of simultaneously acquiring multiphoton and reflectance confocal images at up to 27 frames per second with 256 × 256 pixel resolution without the use of exogenous contrast agents. A single femtosecond laser excitation source is used for all channels ensuring perfect image registration between the two‐photon fluorescence (TPF), second harmonic generation (SHG), and reflectance confocal microscopy (RCM) images. Images and videos acquired with the system show that the three imaging channels provide complementary information in in vivo human skin measurements. In the epidermis, cell boundaries are clearly seen in the RCM channel, while cytoplasm is better seen in the TPF imaging channel, whereas in the dermis, SHG and TPF channels show collagen bundles and elastin fibers, respectively. The demonstrated fast imaging speed and multimodal imaging capabilities of this MPM/RCM instrument are essential features for future clinical application of this technique. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
57.
Monitoring vegetation recovery after China’s May 2008 Wenchuan earthquake using Landsat TM time-series data: a case study in Mao County 总被引:2,自引:0,他引:2
Tao Lu Hongcheng Zeng Yan Luo Qian Wang Fusun Shi Geng Sun Yan Wu Ning Wu 《Ecological Research》2012,27(5):955-966
The Wenchuan earthquake (Richter scale 8) on 12 May 2008 in southwestern China caused widespread ecosystem damage in the Longmenshan area. It is important to evaluate natural vegetation recovery processes and provide basic information on ecological aspects of the recovering environment after the earthquake. To circumvent the weather limits of remote sensing in the Wenchuan earthquake-hit areas, and to meet the need for regional observation analyses, three Landsat TM images pre- and post-earthquake in Mao County were used for analysis. Post-earthquake normalized difference vegetation index (NDVI) values were compared to pre-earthquake values with an NDVI-based index differencing method to determine the extent to which the vegetation was damaged in relation to the pre-earthquake pattern, and the rate of recovery was evaluated. The spatial characteristics of vegetation loss and natural recovery patterns were analyzed in relation to elevation, slope and aspect. The results indicated that severely damaged sites occurred mainly in river valleys, within a range of 1,500?C2,500?m elevation and on slopes of 25?C55°. The distance from rivers, rather than the distance from active faults, controls the damage patterns. After 1?year of natural regeneration, 36?% of the destroyed areas showed a decrease in NDVI value, 28.8?% showed very little change, 19.1?% showed an increase, and 16.1?% also increased with a recovery rate greater than 100?%. Moreover, there is a good correlation between recovery rate and both slope and elevation, but recovery patterns in the damaged area are complicated. Our results indicate that natural recovery in this arid valley is a slow process. 相似文献
58.
硬覆盖对土壤水热传输及作物生长发育影响的试验研究 总被引:2,自引:0,他引:2
河北省盐渍区农业水资源非常紧缺 ,农业节水势在必行。覆盖保摘技术是农田节水管理的重要措施之一 ,国内外对此有过不少研究报道。但多集中在地膜、秸秆、砂砾和化学喷涂等覆盖材料上 ,这些覆盖材料在使用中有种种不理想之处 ,如地膜覆盖容易造成残膜的“白色污染” ,并且使用年限短 ,降水不易入渗 ,中耕、除草、施肥困难 ,使作物抗病力差等[1 ] ;秸秆覆盖容易使秸秆中的毒素物质与作物间发生生化它感现象 ,影响作物生长[2 ] 。化学喷涂除了不利于农事作业外 ,还可能造成土壤污染。为此 ,我们在中国科学院南皮试区盐渍土上试用了一种新型覆… 相似文献
59.
Y Tanaka L Zeng H Shiraki H Shida H Tozawa 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(1):354-360
We have generated a number of mAb against various epitopes on the external envelope glycoprotein, gp46, of human T cell leukemia virus type I (HTLV-I) from a WKA rat immunized with a recombinant vaccinia virus containing the HTLV-I env gene. Among these mAb, one group of mAb, represented by a mAb designated LAT-27, could neutralize the infectivity of HTLV-I, as determined by a HTLV-I-mediated cell fusion inhibition assay. LAT-27 also interfered with transformation of normal T lymphocytes by HTLV-I in vitro. An antibody-binding assay using overlapping synthetic oligopeptides showed that LAT-27 bound specifically to 10-mer peptides that contained the gp46 amino acid sequence 191-196 (Leu-Pro-His-Ser-Asn-Leu). Antibodies from HTLV-I+ humans interfered with the binding of LAT-27 to gp46 Ag. Sera from rabbits immunized with a LAT-27-reactive peptide, 190-199, conjugated with OVA, but not sera from OVA-immunized rabbits, reacted with gp46 Ag and neutralized infectivity of HTLV-I. These results show that the HTLV-I neutralization epitope recognized by LAT-27 locates to the gp46 amino acids 191-196, and that immunization with a peptide containing the LAT-27 epitope can elicit an HTLV-I neutralizing antibody response. 相似文献
60.