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951.
Ki-Soo Park Yong-Soon Lee Kyung-Sun Kang 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(4):343-348
Mesenchymal stem cells (MSCs) have the capabilities for self-renewal and differentiation into cells with the phenotypes of bone, cartilage, neurons and fat cells. These features of MSCs have attracted the attention of investigators for using MSCs for cell-based therapies to treat several human diseases. Because bone marrow-derived cells, which are a main source of MSCs, are not always acceptable due to a significant drop in their cell number and proliferative/differentiation capacity with age, human umbilical cord blood (UCB) cells are good substitutes for BMCs due to the immaturity of newborn cells. Although the isolation of hematopoietic stem cells from UCB has been well established, the isolation and characterization of MSCs from UCB still need to be established and evaluated. In this study, we isolated and characterized MSCs. UCB-derived mononuclear cells, which gave rise to adherent cells, exhibited either an osteoclast or a mesenchymal-like phenotype. The attached cells with mesenchymal phenotypes displayed fibroblast-like morphologies, and they expressed mesenchym-related antigens (SH2 and vimentin) and periodic acid Schiff activity. Also, UCB-derived MSCs were able to transdifferentiate into bone and 2 types of neuronal cells, in vitro. Therefore, it is suggested that the MSCs from UCB might be a good alternative to bone marrow cells for transplantation or cell therapy. 相似文献
952.
[目的]增施氮肥是实现水稻高产最为重要的措施之一,但过量施用氮肥会降低氮肥吸收利用率并造成氮素面源污染.合理的每穴苗数通过调节稻田基本苗数构建高产群体起点,但通过增加每穴苗数降低施氮量能否同步实现水稻高产及氮素高效利用目前还不清楚.旨在探索每穴苗数及氮肥用量对构建晚籼稻高产氮高效群体的协同调控效果.[方法]于2017—2018年,选用五优308及天优华占为晚籼稻材料,设CK(每穴2苗和N 180 kg/hm2)、T1(每穴3苗和N 144 kg/hm2)及T2(每穴4苗和N 126 kg/hm2)等3个处理,测定了水稻干物质生产、叶面积指数、产量及氮素吸收利用.[结果]随着增苗减氮调控程度增加,两品种产量均先增后降.与CK处理相比,五优308及天优华占品种T1处理产量分别增加0.36%~0.38%及8.73%~10.01%,其中天优华占T1处理与CK处理产量间差异达显著水平;天优华占T2处理产量增加0.95%~1.72%,而五优308品种T2处理产量却显著降低7.46%~7.96%.增苗减氮促进晚籼稻有效穗数增加,每穗粒数降低,结实率先增后降,千粒质量无显著变化.两品种抽穗期及成熟期的叶面积指数及幼穗分化期至成熟期的光合势均先增后降,五优308作物生长速率、总干物质量降低,而天优华占作物生长速率、总干物质量却均先增后降.总吸氮量降低,氮素偏生产力增加、氮素吸收利用率、生理利用率及农学利用率均先增后降.[结论]T1处理可同步协调"增苗"与"减氮"二者关系,可有效构建晚籼稻高产氮高效群体,但具体调控效果因品种而异. 相似文献
953.
营林技术决策系统的研究与开发 总被引:1,自引:0,他引:1
A set of forestation decision-making system which covers 140 tree species growing extensively in Zhejiang Province including coniferous forest, broad-leaf forest, production forest, and bamboo forest, was developed by cooperation of silvicultural techniques and computer programming based on the experience of forestry management and mathematical models. It can be easily operated to help user selecting tree species in given site types and optimize their benefits, which advances the efficiency of forestation and improves the rationality of decision-making. 相似文献
954.
[目的]探讨库尔勒香梨有机肥适宜用量,为健康安全果品生产提供理论依据.[方法]设置不同有机肥施用量处理,观测各试验树的生长发育及产量品质.[结果]施用有机肥的库尔勒香梨树与对照相比,新梢平均生长量提高0.40;~ 3.66;,叶面积提高0.77;~1.48;,光合速率提高12.88; ~23.33;,单株产量提高16.32; ~ 37.09;,VC含量提高5.28;~14.85;,可溶性固形物含量提高2.03;~3.93;,固酸比提高6.95;~ 9.02;;但有机肥对果形指数和单果重的影响不明显.[结论]有机肥对库尔勒香梨枝叶生长、产量及果实品质等有明显促进作用;60 kg/株施肥量处理下的库尔勒香梨在多项观测指标上表现较好. 相似文献
955.
956.
Chunmei Wang Yiping Zhang Dejun Han Zhensheng Kang Guiping Li Aizhong Cao Peidu Chen 《Euphytica》2008,159(3):359-366
Stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating wheat diseases worldwide. Triticum aestivum-Haynaldia villosa 6VS/6AL translocation lines carrying the Yr26 gene on chromosome 1B, are resistant to most races of Pst used in virulence tests. In order to better utilize Yr26 for wheat improvement, we attempted to screen SSR and EST-based STS markers closely linked with Yr26. A total of 500 F2 plants and the F2:3 progenies derived from a cross between 92R137 and susceptible cultivar Yangmai 5 were inoculated with race CYR32. The analysis
confirmed that stripe rust resistance was controlled by a single dominant gene, Yr26. Among 35 pairs of genomic SSR markers and 81 pairs of STS markers derived from EST sequences located on chromosome 1B, Yr26 was flanked by 5 SSR and 7 STS markers. The markers were mapped in deletion bins using CS aneuploid and deletion lines. The
closest flanking marker loci, Xwe173 and Xbarc181, mapped in 1BL and the genetic distances from Yr26 were 1.4 cM and 6.7 cM, respectively. Some of these markers were previously reported on 1BS. Eight common wheat cultivars
and lines developed from the T. aestivum-H. villosa 6VS/6AL translocation lines by different research groups were tested for presence of the markers. Five lines with Yr26 carried the flanking markers whereas three lines without Yr26 did not. The results indicated that the flanking markers should be useful in marker-assisted selection for incorporating
Yr26 into wheat cultivars. 相似文献
957.
本试验旨在研究不同浓度苜蓿黄酮对体外培养奶牛乳腺上皮细胞增殖与抗氧化的影响。试验利用含不同浓度0 μg/mL(对照组)、25 μg/mL(试验Ⅰ)、50 μg/mL(试验Ⅱ)、75 μg/mL(试验Ⅲ)、100 μg/mL(试验Ⅳ)苜蓿黄酮的培养基进行细胞培养。结果表明,1)细胞培养第3天,各组细胞增殖无显著差异,但第5天试验Ⅱ~Ⅳ组细胞增殖能力极显著高于对照组和试验I组(P<0.01)。2)试验Ⅱ~Ⅳ组一氧化氮(NO)水平明显高于对照组与试验Ⅰ组,且差异极显著(P<0.01)。试验Ⅰ组、Ⅱ组、Ⅳ组的乳酸脱氢酶(LDH)活性显著低于对照组与试验Ⅲ组,且差异极显著(P<0.01),但对照组与试验Ⅲ组差异不显著。3)试验Ⅳ组细胞内过氧化氢酶(CAT)含量极显著高于其他各组(P<0.01),而试验Ⅲ组丙二醛(MDA)含量极显著低于其他各组(P<0.01);试验Ⅱ和Ⅲ组的谷胱甘肽过氧化物酶(GSH-PX)活性极显著高于其他各组(P<0.01),而各处理组细胞的超氧化物歧化酶(SOD)含量差异不显著。4)试验Ⅱ和Ⅲ组细胞p53、Caspase-3、SOCS3和STAT1基因的相对表达量极显著低于对照组(P<0.01)。因此,苜蓿黄酮能够促进体外培养奶牛乳腺上皮细胞的增殖,提高细胞抗氧化的能力,抑制细胞凋亡,其中添加浓度为75 μg/mL组效果最好。 相似文献
958.
为制备牛病毒性腹泻病毒(BVDV)的Core蛋白及其多克隆抗体,根据Core蛋白的编码基因序列,设计合成一对特异性引物,利用RT-PCR扩增BVDV Core基因并定向插入Pet30a载体中,构建重组质粒Pet30a-Core,经酶切鉴定后转化大肠埃希菌TOP 10感受态细胞,筛选获得阳性重组菌,以IPTG进行诱导后成功表达出分子质量为20 ku的重组Core蛋白。将诱导表达的蛋白产物经融合蛋白的Ni柱亲和法进行纯化,利用纯化的重组蛋白免疫新西兰白兔制备多克隆抗体,并利用间接ELISA法测出多克隆抗体效价达到1∶512 000。蛋白质印迹法(Western blot)和间接免疫荧光试验(IFA)证实,多克隆抗体可与细胞中的BVDV抗原发生反应,具有良好的免疫原性和特异性。本实验成功制备了BVDV重组Core蛋白的兔源多克隆抗体,为BVDV的检测及其Core蛋白功能研究奠定了基础。 相似文献
959.
960.
Paddy and Water Environment - Soil salinization is a major soil degradation threat worldwide. Sparse vegetation and soil desertification are widespread phenomena in coastal saline land due to high... 相似文献