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51.
Acetate metabolism was studied with Saccharomyces cerevisiae diploid strain G2-2 in sporulating culture, asporogenic diploid strains 3c × a and 3c × 3a, and respiratory deficient haploid strain 3c (asporogenic). Acetate in a sporulating medium was utilized by sporogenic and asporogenic diploid yeasts linearly with time. Activities of aconitase, NADP-linked isocitrate dehydrogenase, and succinate dehydrogenase initially increased in the cell-free homogenate of either strain. Activity of glucose-6-phosphate dehydrogenase decreased. Isocitrate lyase activity increased remarkably in the sporogenic strain but not in the asporogenic strain. The rate of production of 14CO2 from 14C-1-acetate was accelerated more than from 14C-2-acetate in intact cells of the sporogenic strain during sporulating culture. Fractionation of radioactive cell substances showed remarkable lipid synthesis. Accumulation and reutilization of cold acid-soluble precursor substances occurred during sporogenesis. The role of glyoxylate and tricarboxylate cycle enzymes in sporulation is discussed.  相似文献   
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We report on a roundtable event hosted in Singapore that sought to identify some of the ethical and regulatory challenges in translating autologous cell-based interventions, particularly those claiming to involve stem cells, into safe and effective therapies and to propose some solutions to encourage responsible innovation with these products. Challenges are identified in the three areas of cell manufacturing and processing, innovative uses of autologous cells in clinical practice and standards of evidence. Proposed solutions are discussed within a co-operative model of statutory laws and regulations that can enable product development with autologous cells and professional codes and standards that can encourage ethical conduct in clinical practice. Future research should be directed toward establishing regional networks for the development of internationally consistent standards in manufacturing and ethical codes of conduct for innovating with stem cells, and other autologous cells, and fostering ongoing exchange between jurisdictions.  相似文献   
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Abstract:  A new genus and species of an elasmosaurid plesiosaur, Futabasaurus suzukii , is described based on a partial skeleton from the Inoceramus amakusensis Zone (Lower Santonian, Upper Cretaceous) of the Irimazawa Member of the Tamayama Formation, Futaba Group, in Fukushima Prefecture, Japan. The new taxon is characterized by a number of characters such as the wide space between the orbit and external naris, posterior extension of the interclavicle, relatively long humerus and prominent femoral muscle scar. The holotype includes a partial skull and mandible, posterior cervicals to sacrals, ribs, clavicular arch, pelvic girdle and four limbs. The remains are mostly in articulation, and exhibit evidence of predation/scavenging by sharks. The distribution of elasmosaurid species in the circum-Pacific region remains unclear due to the lack of diagnostic materials. The occurrence of F. suzukii is geographically and stratigraphically significant, because it allows species-level comparison; as a diagnosable elasmosaurid specimen, F. suzukii is the first and the oldest from the northern Pacific.  相似文献   
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Species in the Miscanthus genus have been proposed as biofuel crops that have potential to mitigate elevated atmospheric carbon dioxide (CO2) levels and nitrous oxide (N2O) and methane (CH4) emissions. Miscanthus sinensis is widespread throughout Japan and has been used for biomass production for centuries. We assessed the carbon (C) budget and N2O and CH4 emissions over the growing season for 2 years in a M. sinensis‐dominated grassland that was naturally established around 1972 in Tomakomai, Hokkaido, Japan, which is near the northern limit for M. sinensis grassland establishment on Andisols. Average C budget was ?0.31 Mg C ha?1, which indicates C was released from the grassland ecosystem to the atmosphere. Dominant components in the C budget appeared to be aboveground net primary production of plants (1.94–2.80 Mg C ha?1) and heterotrophic respiration (2.27–3.11 Mg C ha?1). The measurement of belowground net primary production (BNPP) of plants in the M. sinensis grassland was extremely variable, thus only an approximate value could be calculated. Mean C budget calculated with the approximated BNPP value was 1.47 and ?0.23 Mg C ha?1 for 2008 and 2009, respectively. Given belowground biomass (9.46–9.86 Mg C ha?1) was 3.1–6.5 times higher than that of aboveground biomass may provide additional evidence suggesting this grassland represents a C sink. Average CH4 emissions across years of ?1.34 kg C ha?1 would indicate this grassland acts as an atmospheric CH4 sink. Furthermore, average N2O emissions across years were 0.22 kg N ha?1. While the site may contribute N2O to the atmosphere, this value is lower compared with other grassland types. Global warming potential calculated with the approximated BNPP value was ?5.40 and 0.95 Mg CO2 Eq ha?1 for 2008 and 2009, respectively, and indicates this grassland could contribute to mitigation of global warming.  相似文献   
56.
The genus Amraica Moore, 1888 in China is reviewed. In addition to the four species and three subspecies already known, one new species, A. prolata sp. nov. is described and one newly recorded species, A. ferrolavata ( Walker, 1863 (imprint 1862) ) is redescribed. The generic characters, based on all species, are summarized. Illustrations of external features and genitalia are presented.  相似文献   
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Molecular phylogeny of wood mice (Apodemus, Muridae) in East Asia   总被引:2,自引:0,他引:2  
Sequences of the mitochondrial cytochrome b (1140 bp) and nuclear IRBP (1152 bp) genes were used to assess the evolutionary history of Apodemus , using the complete set of Asian species. Our results indicate that speciation in Asia involved three radiations, which supports an earlier study. The initial radiation yielded A. argenteus (Japanese endemic), A. gurkha (Nepalese endemic), and the ancestral lineage of the remaining Asian species. This lineage subsequently diverged into four groups: agrarius-chevrieri ( agrarius group), draco-latronum-semotus ( draco group), A. peninsulae , and A. speciosus (Japanese endemic). The final step consisted of divergence within two species groups as a consequence of the geography of the Yunnan-Guizhou plateau and Taiwan. The ecological ability of two Apodemus species to inhabit one locality via niche partitioning likely drove the second radiation and shaped the basic geographical pattern seen today: A. argenteus and A. speciosus in Japan, A. agrarius and A. peninsulae in northern China, and the A. agrarius and A. draco groups in southern China. The three radiations are estimated to have occurred 7.5, 6.6, and 1.8–0.8 Mya respectively, using the IRBP clock, based on rat–mouse divergence 12 Mya.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80 , 469–481.  相似文献   
60.
The genus Cercidiphyllum is considered to be a primitive, relictual angiosperm, with two extant species occurring in limited areas of East Asia. We developed seven microsatellite markers for Cercidiphyllum japonicum, of which, five showed a clear, strong single band for each allele. The average number of alleles and observed heterozygosity were 26.2 and 0.82, respectively. Three pairs of polymerase chain reaction primers successfully amplified the DNA of the other species, Cercidiphyllum magnificum.  相似文献   
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