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Nucleotide sequences of the small-subunit (SSU) ribosomal DNA were determined forPelvetia babingtonii, P. canaliculate, Pelvetiopsis limitata, andAscophyllum nodosum in the family Fucaceae. A total of 1755 positions were aligned for the whole sequence. The positional differences in the primary structure among the taxa ranged from 16 to 30 nucleotide changes in pairwise comparisons. There was a minimum divergence betweenPs. limitata andP. babingtonii while a maximum betweenPs. limitata andP. canaliculata. The SSU rDNA trees showed that the genusPelvetia was not monophyletic and the genusPelvetiopsis was not closely related toPelvetia. Our results suggest that the taxonomic revision of the genusPelvetia as well as the family Fucaceae is needed based on detailed morphological observations.  相似文献   
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Calli were induced from 300,000 embryos isolated from immature to mature stage of seeds collected on late September from 14 elite trees. When the embryos were cultured onto plastic Petri-dish containing 20 mL of modified B5 basal medium supplemented with 3% (w/v) sucrose, 500 mg/L casein hydrolysate, 250 mg/L myo-inositol, 0.5% (w/v) polyvinyl polypyrrolidon (PVPP), 2×MS vitamins, 0.5 mg/L gibberellic acid, and 10 mg/L 2,4-D after 2 weeks of culture, yellowish-white calli were immediately formed on the surfaces of embryos, and subcultured for 4 weeks in same culture medium. Because most of calli maintained for more than 3 months were revealed differences in their colors, surface texture, and growth rate, visual selection was made for first round screening. When the size of visually selected calli larger than 19 mm in their diameter were inoculated, persistent proliferation was observed. Among the plating methods tested for the selection of rapid growing cell lines at single cell and/or small cell aggregate level, 2-layer spread plating revealed as the best for single cell cloning. To enhance cell growth and maintain high rate of viability for long-term culture of yew cells in bioreactor, final cell volume less than 50% in SCV seemed to be the best. Time course study revealed that 30% of inoculum density was suitable for fed batch culture. Among the tested conditional media, the rate of 1∶2 (old medium: fresh medium) was recorded at the best for cell growth.  相似文献   
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Cozijnsen  L.  Braam  R. L.  Bakker-de Boo  M.  Otten  A. M.  Post  J. G.  Schermer  T.  Bouma  B. J.  Mulder  B. J. M. 《Netherlands heart journal》2022,30(4):207-211
Netherlands Heart Journal - To determine the prevalence of undiagnosed bicuspid aortic valve (BAV) and isolated aortic dilatation in first-degree relatives (FDRs) of patients with isolated BAV and...  相似文献   
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Despite numerous studies on late embryogenesis abundant (LEA) proteins, their functions, roles, and localizations during developmental stages in arthropods remain unknown. LEA proteins protect crucial proteins against osmotic stress during the development and growth of various organisms. Thus, in this study, fluorescence in situ hybridization was used to determine the crucial regions protected against osmotic stress as well as the distinctive localization of group 3 (G3) LEA+ cells during brine shrimp development. Several cell types were found to synthesize G3 LEA RNA, including neurons, muscular cells, APH‐1+ cells, and renal cells. The G3 LEA+ neuronal cell bodies outside of the mushroom body projected their axonal bundles to the central body, but those inside the mushroom body projected their axonal bundles toward the deutocerebrum without innervating the central body. The cell bodies inside the mushroom body received axons of the G3 LEA+ sensory cells at the medial ventral cup of the nauplius eye. Several glands were found to synthesize G3 LEA RNA during the nauplius stages of brine shrimp, including the sinus, antennal I and II, salt, and three ectodermal glands. This study provides the first demonstration of the formation of G3 LEA+ sinus glands at the emergence stages of brine shrimp. These results suggest that G3 LEA protein is synthesized in several cell types. In particular, specific glands play crucial roles during the emergence and nauplius stages of brine shrimp.  相似文献   
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Ip  Yuen K.  Hiong  Kum C.  Teng  Joey H. Q.  Boo  Mel V.  Choo  Celine Y. L.  Wong  Wai P.  Chew  Shit F. 《Coral reefs (Online)》2020,39(2):451-465
Coral Reefs - Giant clams flourish in nutrient-poor waters of tropical Indo-Pacific because they live in symbiosis with extracellular dinoflagellates (zooxanthellae) and receive photosynthates from...  相似文献   
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Presenilin (PS) is involved in many cellular events under physiological and pathological conditions. Previous reports have revealed that PS deficiency results in hyperproliferation and resistance to apoptotic cell death. In the present study, we investigated the effects of PS on β-catenin and cell mortality during serum deprivation. Under these conditions, PS1/PS2 double-knockout MEFs showed aberrant accumulation of phospho-β-catenin, higher ROS generation, and notable cell death. Inhibition of β-catenin phosphorylation by LiCl reversed ROS generation and cell death in PS deficient cells. In addition, the K19/49R mutant form of β-catenin, which undergoes normal phosphorylation but not ubiquitination, induced cytotoxicity, while the phosphorylation deficient S37A β-catenin mutant failed to induce cytotoxicity. These results indicate that aberrant accumulation of phospho-β-catenin underlies ROS-mediated cell death in the absence of PS. We propose that the regulation of β-catenin is useful for identifying therapeutic targets of hyperproliferative diseases and other degenerative conditions.  相似文献   
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