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目的体外分离培养、扩增人脐带间充质干细胞(h UC-MSC)和人骨髓间充质干细胞(h BM-MSC),并对其生物学特性进行比较。方法采用组织块贴壁法从足月胎儿脐带分离、纯化和培养h UC-MSC,健康成人骨髓肝素抗凝后,采用密度梯度离心法分离、纯化和培养h BM-MSC;用倒置显微镜观察两种细胞的形态及细胞生长增殖情况,流式细胞仪分析检测第3代细胞表面标志的表达,Von?Kossa染色及油红O染色检测分化潜能。结果镜下两种细胞均为贴壁生长,形态为均一的成纤维细胞样,取相同数量的细胞传代接种后,h UC-MSC的增殖速率快于h BM-MSC,两种细胞具有均一的细胞表型,均表达CD29、CD44、CD105,不表达CD45、CD34、HLA-DR、HLA-G、CD80、CD86,两种细胞都有成骨、成脂分化潜能,但h UC-MSC的分化潜能更强。结论 h UC-MSC与h BM-MSC具有相似的生物学特性,且前者具有更强的增殖能力和分化潜能,h UC-MSC有望成为h BMMSC理想的替代来源。 相似文献
105.
Lucie J. Rochard Irving T.C. Ling Yawei Kong Eric C. Liao 《Journal of visualized experiments : JoVE》2015,(104)
Development of the vertebrate craniofacial structures requires precise coordination of cell migration, proliferation, adhesion and differentiation. Patterning of the Meckel''s cartilage, a first pharyngeal arch derivative, involves the migration of cranial neural crest (CNC) cells and the progressive partitioning, proliferation and organization of differentiated chondrocytes. Several studies have described CNC migration during lower jaw morphogenesis, but the details of how the chondrocytes achieve organization in the growth and extension of Meckel’s cartilage remains unclear. The sox10 restricted and chemically induced Cre recombinase-mediated recombination generates permutations of distinct fluorescent proteins (RFP, YFP and CFP), thereby creating a multi-spectral labeling of progenitor cells and their progeny, reflecting distinct clonal populations. Using confocal time-lapse photography, it is possible to observe the chondrocytes behavior during the development of the zebrafish Meckel’s cartilage.Multispectral cell labeling enables scientists to demonstrate extension of the Meckel’s chondrocytes. During extension phase of the Meckel’s cartilage, which prefigures the mandible, chondrocytes intercalate to effect extension as they stack in an organized single-cell layered row. Failure of this organized intercalating process to mediate cell extension provides the cellular mechanistic explanation for hypoplastic mandible that we observe in mandibular malformations. 相似文献
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A 32-year old housewife, living in Seoul, recognized incidentally a painless mass at the left chest wall. During later 3 months, she experienced spontaneous swelling and regression of the mass repeatedly for 4 times. Surgical resection showed a granuloma at anterior serratus muscle containing a nearly matured adult of Fasciola species without vitellaria and uterus. This is the 11th human fascioliasis and the first extra-abdominal infection reported in Korea. 相似文献
108.
Xiangjun Kong Aziz Khan Zhiling Li Jingyi You Fazal Munsif Haodong Kang Ruiyang Zhou 《Saudi Journal of Biological Sciences》2020,27(12):3691-3699
Chalcone synthase (CHS) is a key enzyme and producing flavonoid derivatives as well play a vital roles in sustaining plant growth and development. However, the systematic and comprehensive analysis of CHS genes in island cotton (G. barbadense) has not been reported yet especially response to cytoplasmic male sterility (CMS). To fill this knowledge gap, a genome-wide investigation of CHS genes were studied in island cotton. A total of 20 GbCHS genes were identified and grouped into five GbCHSs. The gene structure analysis revealed that most of GbCHS genes consisted of two exons and one intron, and 20 motifs were identified. Twenty five pairs duplicated events (12 GbCHS genes) were identified including 23 segmental duplication pairs and two tandem duplication events, representing that GbCHS gene family amplification mainly owned to segmental duplication events and evolving slowly. Gene expression analysis exhibited that the GbCHS family genes presented a diversity expression patterns in various organs of cotton. Coupled with functional predictions and gene expression, the abnormal expression of GbCHS06, 10, 16 and 19 might be associated with pollen abortion of CMS line in island cotton. Conclusively, GbCHS genes exhibited diversity and conservation in many aspects, which will help to better understand functional studies and a reference for CHS research in island cotton and other plants. 相似文献
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Yan Xiao Junbing Tang Hua Qing Changfang Zhou Weijing Kong Shuqing An 《Hydrobiologia》2011,658(1):353-363
The purpose of this article was to study the trade-offs among vegetative growth, clonal, and sexual reproduction in an aquatic
invasive weed Spartina alterniflora that experienced different inundation depths and clonal integration. Here, the rhizome connections between mother and daughter
ramets were either severed or left intact. Subsequently, these clones were flooded with water levels of 0, 9, and 18 cm above
the soil surface. Severing rhizomes decreased growth and clonal reproduction of daughter ramets, and increased those of mother
ramets grown in shallow and deep water. The daughter ramets disconnected from mother ramets did not flower, while sexual reproduction
of mother ramets was not affected by severing. Clonal integration only benefited the total rhizome length, rhizome biomass,
and number of rhizomes of the whole clones in non-inundation conditions. Furthermore, growth and clonal reproduction of mother,
daughter ramets, and the whole clone decreased with inundation depth, whereas sexual reproduction of mother ramets and the
whole clones increased. We concluded that the trade-offs among growth, clonal, and sexual reproduction of S. alterniflora would be affected by inundation depth, but not by clonal integration. 相似文献
110.
Enrichment of a common wheat genetic map and QTL mapping for fatty acid content in grain 总被引:2,自引:0,他引:2
Ying-ying Wang Xian-yin Sun Yan Zhao Fan-mei Kong Ying Guo Gui-zhi Zhang Yan-yan Pu Ke WuSi-shen Li 《Plant science》2011,181(1):65-75
DArT and SSR markers were used to saturate and improve a previous genetic map of RILs derived from the cross Chuan35050 × Shannong483. The new map comprised 719 loci, 561 of which were located on specific chromosomes, giving a total map length of 4008.4 cM; the rest 158 loci were mapped to the most likely intervals. The average chromosome length was 190.9 cM and the marker density was 7.15 cM per marker interval. Among the 719 loci, the majority of marker loci were DArTs (361); the rest included 170 SSRs, 100 EST-SSRs, and 88 other molecular and biochemical loci. QTL mapping for fatty acid content in wheat grain was conducted in this study. Forty QTLs were detected in different environments, with single QTL explaining 3.6-58.1% of the phenotypic variations. These QTLs were distributed on 16 chromosomes. Twenty-two QTLs showed positive additive effects, with Chuan35050 increasing the QTL effects, whereas 18 QTLs were negative with increasing effects from Shannong483. Six sets of co-located QTLs for different traits occurred on chromosomes 1B, 1D, 2D, 5D, and 6B. 相似文献