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111.
Traditional concept has been that hematopoietic stem cells (HSC) are tissue-specific stem cells, which are restricted to generate the cell types of the blood and immune system. However, recent studies have shown that there is a higher plasticity of the HSC than previous expected, it can be induced to transdifferentiated into mature cells of other nonhematopoietic organs after transplantation in vivo. In this article, the recent advances in the plasticity of HSC and its potential clinical application are reviewed. 相似文献
112.
XIAO Qing-zhong LI Hao-wei WEN Guan-mei HUANG Shao-hua ZHANG Xiu-ming LI Yan LI Shu-nong 《园艺学报》2002,18(10):1179-1182
AIM: To investigate the differentiation from adult rat and human bone marrow mesenchymal stem cells (BMMSCs) into neuron with musk polypeptide (Mu-P).METHODS: Adult rat and human BMMSCs were induced with Mu-P.Neuron-specific enolase (NSE),neurofilament (NF),Nestin,glial fibrillary acidic protein (GFAP) were detected by immunohistochemistry.RESULTS: Simple methods with Mu-P induced adult rat and human BMMSCs exhibiting a neuronal phenotype,expressing Nestin at 3 hours to 5 hours,and expressing NE and NF at 5 hours to 7 days.But the neuron-like cells didn't express the glial astrocyte marker GFAP.CONCLUSION: Adult rat and human BMMSCs can be induced to differentiate into neurons with Mu-P. 相似文献
113.
为弄清火龙果茎腐病的病原和分类地位,并进一步为该病害的有效防治提供理论依据。本研究从琼海、临高、陵水等地广泛采集病样。经田间症状调查、组织纯化培养、病原形态观察、致病力测定、真菌ITS序列和系统进化分析,鉴定了该病害的病原。结果表明:病原分离物具有典型的镰刀菌形态特征,菌丝浓密,产生紫色素,小型分生孢子新月形,大型分生孢子镰刀形,有多个隔;而在ITS序列分析中,代表菌株47A4和47A5与NCBI数据库中尖孢镰刀菌的多条ITS序列(登录号分别为KJ653447.1, DQ535184.1和KM268692.1)相似性达100%;系统进化树上,47A4和47A5与尖孢镰刀菌聚在同一分支上,遗传距离最近,而与非纯培养镰刀菌克隆3.91E在不同分支上,遗传距离远。结合形态特征、序列分析和系统进化分析,将火龙果茎腐病的病原鉴定为尖孢镰刀菌(Fusarium oxysporum)。研究结果对火龙果茎腐病流行规律、致灾机理的研究具有重要的指导作用。 相似文献
114.
氮肥对杂交小麦果聚糖积累与转运及其杂种优势的影响 总被引:1,自引:0,他引:1
氮肥影响作物的碳氮代谢及生长发育。选用6个杂交小麦及其7个亲本材料在施氮(200 kg /hm2)和不施氮(0 kg /hm2)条件下,比较研究了不同生育期不同器官果聚糖的积累与转运及其杂种优势。无论施氮与否茎鞘和总麦草中果聚糖的积累模式基本相似。茎鞘是贮存果聚糖的主要营养器官,分配了总麦草果聚糖积累量的63%~87%,并在开花期其积累量达最大值。总麦草转运的85%以上的果聚糖来源于茎鞘,其对籽粒产量的贡献率最大(9.42%~19.36%)。氮缺乏减少叶片中果聚糖的积累量,但增加茎鞘和总麦草中果聚糖的积累量。穗轴及颖壳、茎鞘和总麦草的果聚糖积累在挑旗期、抽穗期和开花期存在一定的杂种优势(4.7%~51.7%),叶片、茎鞘和总麦草的果聚糖转运量、转运率也具有较强的杂种优势,施氮增强叶片中果聚糖的转运优势,但减弱茎鞘和总麦草中的转运优势。结果说明,杂交品种比其亲本具有更强的果聚糖转运能力,施氮对茎鞘果聚糖的积累与转运及其杂种优势均有抑制作用。 相似文献
115.
冬小麦穗—茎维管联络结构及其形成过程对幼穗生长发育的影响 总被引:1,自引:0,他引:1
本文系统研究了冬小麦穗-茎维管系统的联络特点及其形成过程,分析了其在小麦幼穗发育中所起的作用。结果表明,小麦穗部维管束主要在旗叶节与茎内维管系统联络,其次是倒二节。其联系是逐步完善的。在幼穗的护颖分化-小花分花以前,穗、茎之间缺少维管联络;到雌雄蕊分化期,穗、茎维管系统依靠原形成层束达到初步联络;药隔形成期时,这种联络已比较完善,达到筛管联结;直到四分体形成期时,穗-茎维管系统的联络才发育完善,同 相似文献
116.
117.
AIM:To evaluate the method of inducing mouse embryonic stem (ES) cells in vitro to differentiate into cardiomyocytes without using any chemical reagents.METHODS:BRL conditioned medium was used to promote the growth of ES cells and maintain them in an undifferentiated state before the experiment of differentiation. Then a three-step method including ES cell culture in hanging drops and in suspending was used to induce the differentiation of ES cells. RESULTS:Rhythmically contracting cells were observed among differentiated cells, which were proved to be cardiomyocytes with electron microscope and immunocytochemistry. CONCLUSION:A simple and economical method was established to induce mouse ES cells cultured in vitro to differentiate into cardiomyocytes without using any chemical reagents. 相似文献
118.
119.
The ontogenesis of Zea mays L. and their modification by plant growth regulators
During a period of 2 years with the maize variety Santos , the effects of the plant growth regulators CCC and RSW 0411 upon vegetative and generative development were tested by pot experiments. The experiments were carried out to optimize the PGR application to maize and to interpret possible PGR effects. The application shah improve the resistance to lodging by a reduction of ear–and plant height as well as by an increase of stalk diameter. At the same time, the sink-capacity of the ear shah increase because this is lucrative to all specializations of corn production.
The PGR RSW strongly reduced the stem elongation during the growing season after an application in ES 21. The basal stem diameter increased highly significant. The PGR CCC did not obviously effect the vegetative development of maize.
RSW suppressed the branching of the tassel after an application in ES 21. Later applications did not disturb the tassel development, because the tassel were completely differentiated at the application time in ES 31/32 and ES 34/35. High application rates of CCC, applied in ES 31/32 and ES 34/35, increased significantly the grain yield by a higher number of kernels per ear. The 1000 kernels weight remained unchanged. The results of the ear ontogenesis indicated, that the PGR CCC lessened the reduction of female spikelets in the ear during the post-silking period. 相似文献
During a period of 2 years with the maize variety Santos , the effects of the plant growth regulators CCC and RSW 0411 upon vegetative and generative development were tested by pot experiments. The experiments were carried out to optimize the PGR application to maize and to interpret possible PGR effects. The application shah improve the resistance to lodging by a reduction of ear–and plant height as well as by an increase of stalk diameter. At the same time, the sink-capacity of the ear shah increase because this is lucrative to all specializations of corn production.
The PGR RSW strongly reduced the stem elongation during the growing season after an application in ES 21. The basal stem diameter increased highly significant. The PGR CCC did not obviously effect the vegetative development of maize.
RSW suppressed the branching of the tassel after an application in ES 21. Later applications did not disturb the tassel development, because the tassel were completely differentiated at the application time in ES 31/32 and ES 34/35. High application rates of CCC, applied in ES 31/32 and ES 34/35, increased significantly the grain yield by a higher number of kernels per ear. The 1000 kernels weight remained unchanged. The results of the ear ontogenesis indicated, that the PGR CCC lessened the reduction of female spikelets in the ear during the post-silking period. 相似文献
120.