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251.
In conclusion we have shown that: (a) liver N-CAM is a functionally active adhesion molecule, (b) its expression during the morphogenetic processes occurring during Xenopus laevis metamorphosis correlates with morphological changes in the cell-to-cell interaction; (c) Thyroxine is not directely involved in the activation of the expression of liver N-CAM. 相似文献
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R Aufrère M Tempête J P Bohin 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1986,303(3):49-54
The two promoters and the first 65 nucleotides of a gene related to the rrnB operon are localized in the coding sequence of the btuB gene. 相似文献
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Zhang L Yan Q Liu JP Zou LJ Liu J Sun S Deng M Gong L Ji WK Li DW 《Current molecular medicine》2010,10(9):864-875
The ocular lens is a non-vascular and non-innervated transparent organ that plays an important role in vision processing. This unique organ is derived from the embryonic ectoderm of the brain region through a complicated differentiation process in which apoptosis plays a key role. First, when the committed ectoderm becomes thickened and invaginated, the defined number of cells required to form the lens vesicle is partially determined by apoptosis. Second, separation of lens vesicle from the above corneal ectoderm is executed through apoptosis of the lens stalk cells. Finally, differentiation of the lens epithelial cells is controlled by the regulators, most of which are involved in control of apoptosis at multiple signaling steps. The lens is also characterized by continuous growth and differentiation in the adulthood. Through the different stages of growth and differentiation in the adult lens, various stress conditions can induce apoptosis of the lens epithelial cells, leading to eventual non-congenital cataractogenesis. The present review summarizes the current knowledge on the functions and regulators of apoptosis in the ocular lens. 相似文献
256.
Random amplified polymorphic DNA (RAPD) and sequence-related amplified polymorphism (SRAP) analysis were applied to 74 individual plants of Piper spp in Hainan Island. The results showed that the SRAP technique may be more informative and more efficient and effective for studying genetic diversity of Piper spp than the RAPD technique. The overall level of genetic diversity among Piper spp in Hainan was relatively high, with the mean Shannon diversity index being 0.2822 and 0.2909, and the mean Nei's genetic diversity being 0.1880 and 0.1947, calculated with RAPD and SRAP data, respectively. The ranges of the genetic similarity coefficient were 0.486-0.991 and 0.520-1.000 for 74 individual plants of Piper spp (the mean genetic distance was 0.505 and 0.480) and the within-species genetic distance ranged from 0.063 to 0.291 and from 0.096 to 0.234, estimated with RAPD and SRAP data, respectively. These genetic indices indicated that these species are closely related genetically. The dendrogram generated with the RAPD markers was topologically different from the dendrogram based on SRAP markers, but the SRAP technique clearly distinguished all Piper spp from each other. Evaluation of genetic variation levels of six populations showed that the effective number of alleles, Nei's gene diversity and the Shannon information index within Jianfengling and Diaoluoshan populations are higher than those elsewhere; consequently conservation of wild resources of Piper in these two regions should have priority. 相似文献
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Y-W Miao M-S Peng G-S Wu Y-N Ouyang Z-Y Yang N Yu J-P Liang G Pianchou A Beja-Pereira B Mitra M G Palanichamy M Baig T K Chaudhuri Y-Y Shen Q-P Kong R W Murphy Y-G Yao Y-P Zhang 《Heredity》2013,110(3):277-282
Domestic chickens (Gallus gallus domesticus) fulfill various roles ranging from food and entertainment to religion and ornamentation. To survey its genetic diversity and trace the history of domestication, we investigated a total of 4938 mitochondrial DNA (mtDNA) fragments including 2843 previously published and 2095 de novo units from 2044 domestic chickens and 51 red junglefowl (Gallus gallus). To obtain the highest possible level of molecular resolution, 50 representative samples were further selected for total mtDNA genome sequencing. A fine-gained mtDNA phylogeny was investigated by defining haplogroups A–I and W–Z. Common haplogroups A–G were shared by domestic chickens and red junglefowl. Rare haplogroups H–I and W–Z were specific to domestic chickens and red junglefowl, respectively. We re-evaluated the global mtDNA profiles of chickens. The geographic distribution for each of major haplogroups was examined. Our results revealed new complexities of history in chicken domestication because in the phylogeny lineages from the red junglefowl were mingled with those of the domestic chickens. Several local domestication events in South Asia, Southwest China and Southeast Asia were identified. The assessment of chicken mtDNA data also facilitated our understanding about the Austronesian settlement in the Pacific. 相似文献
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Genicot C Christophe B Collart P Gillard M Goossens L Hénichart JP Lassoie MA Moureau F Neuwels M Nicolas JM Pasau P Quéré L Ryckmans T Stiernet F Taverne T Van Keulen BJ 《Bioorganic & medicinal chemistry letters》2003,13(3):437-442
Benzyloxyphenethylpiperazines are a new class of high affinity NK1 receptor antagonists. Oral bioavailability and selectivity can be fine tuned by the nature of the substituents on the basic nitrogen atom. Addition of substituents with a carboxylic acid group led to very selective and orally active NK1 antagonists free of interaction with L-type calcium channels. 相似文献