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121.
Tran Cong Toai Huynh Duy Thao Nguyen Phuong Thao Ciro Gargiulo Phan Kim Ngoc Pham Hung Van D. Michael Strong 《Cell and tissue banking》2010,11(3):269-280
It is well accepted that human umbilical cord blood (UCB) is a source of mesenchymal stem cells (MSCs) which are able to differentiate
into different cell phenotypes such as osteoblasts, chondrocytes, adipocytes, myocytes, cardiomyocytes and neurons. The aim
of this study was to isolate MSCs from human UCB to determine their osteogenic potential by using different kinds of osteogenic
medium. Eventually, only those MSCs cultured in osteogenic media enriched with vitamin D2 and FGF9, were positive for osteocalcin by RT-PCR. All these cells were positive for alizarin red, alkaline phosphatase and
Von Kossa. The results obtained from RT-PCR have confirmed that osteogenesis is complete by expression of the osteocalcin
marker. In conclusion, vitamin D2, at least in vitro, may replace vitamin D3 as an osteogenic stimulator factor for MSC differentiation. 相似文献
122.
G-quadruplexes and Z-DNA are two important non-B forms of DNA architecture. Results on novel structural elements, folding and unfolding kinetics, and interactions with small molecules and proteins have been reported recently for these forms. These results will enhance our understanding of the biology of these structures and provide a platform for drug design. 相似文献
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124.
Genus Pteris from Vietnam and Laos is revised in this paper. Seven species newly reported from Vietnam and Laos are P.argyraea, P.sichuanensis, P.maclurei, P.pseudopellucida, P.setuloso costulata, P.morii, and P.wangiana. 相似文献
125.
126.
A functionally conserved Zn2Cys6 binuclear cluster transcription factor class regulates necrotrophic effector gene expression and host‐specific virulence of two major Pleosporales fungal pathogens of wheat
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128.
In northern Việt Nam the felling of Cupressus for wood and incense has resulted in the decimation of wild cypress populations. Ever since specimens of Cupressus from Việt Nam were first sent to Paris in 1905, they have been inappropriately referred to a variety of names including Cupressus funebris, Cu. torulosa, and synonyms of Callitropsis lusitanica. This taxonomic disarray was somewhat ameliorated in 1994 when a new species—Cu. tonkinensis—was proposed. Unfortunately, the morphological differences between Cu. tonkinensis and similar species were not clearly articulated. As a result, Cu. tonkinensis has generally been ignored or treated as a synonym of Cu. torulosa. These two species can be distinguished by the presence of dimorphic leaves in Cu. tonkinensis and their absence in Cu. torulosa as well as several continuous morphological characteristics including the frequency of resin glands (greater in Cu. tonkinensis) on ultimate segments, and the size of the ovulate cone (smaller in Cu. tonkinensis). The natural habitat occupied by Cu. tonkinensis in a principal coordinates plot of nine monthly climate variables and 40 soil variables is remote from other species. Cupressus tonkinensis habitat is statistically distinct from Cu. chengiana, Cu. gigantea, and Cu. torulosa, but statistically indistinguishable from the habitats of Cu. funebris. 相似文献
129.
Two new species of Lysimachia (Primulaceae), L. vietnamensis L. K. Phan & C. M. Hu and L. verbascifolia C. M. Hu & K. L. Phan from Vietnam are described and illustrated. 相似文献
130.
G-rich oligonucleotides T30695 (or T30923), with the sequence of (GGGT)(4), and T40214, with the sequence of (GGGC)(4), have been reported to exhibit anti-HIV and anticancer activity. Here we report on the structure of a dimeric G-quadruplex adopted by a derivative of these sequences in K(+) solution. It comprises two identical propeller-type parallel-stranded G-quadruplex subunits each containing three G-tetrad layers that are stacked via the 5'-5' interface. We demonstrated control over the stacking of the two monomeric subunits by sequence modifications. Our analysis of possible structures at the stacking interface provides a general principle for stacking of G-quadruplexes, which could have implications for the assembly and recognition of higher-order G-quadruplex structures. 相似文献