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1.
MASAHIRO SATO SHUN-ICHIROH OGATA RYUZO UEDA REIKO NAMIKAWA TOSHITADA TAKAHASHI TAKAO NAKAMURA EIICHI SATO TAKASHI MURAMATSU 《Development, growth & differentiation》1983,25(4):333-344
C-9-1, a monoclonal IgM antibody raised against human null cell acute lymphocytic leukemia cells reacted with restricted regions of embryonic and adult tissues of the mouse. The antigen positive sites in the embryos included embryonic ectoderm, visceral endoderm, trophoblastic cells invading the maternal decidua of 5∼7-day embryos, primordial germ cells of 10∼12-day embryos, epithelium of nasal chamber, the bronchus, Mullerian duct, epididymis and bladder of 12∼17-day embryos. In the adult mice, C-9-1 antigen was detected in renal tubules, a part of stomach, bladder, endometrium and epididymal sperm. Embryonal carcinoma cells, but not endodermal cells of teratocarcinoma expressed the antigen. Thus, C-9-1 antigen showed distribution similar to SSEA-1. However, C-9-1 antigen was not detected in preimplantation embryos, nor in oviduct, both of which are positive for SSEA-1. 相似文献
2.
Young mung bean plants (Phaseolus mungo) were exposed to 14C-shikimateor 14C-quinate in the light. After 8 or 23.5 hr of incubationat 25°C, radioactivities in free and bound amino acids,organic acids, soluble and insoluble carbohydrates, ether-solublefraction and lignin were determined. Shikimic and quinic acidswere separated by the combined use of paper-chromatography andcolumn chromatography. Specific activity of formed quinate orshikimate was only slightly lower than that of fed shikimateor quinate. Specific activities of phenylalanine, tyrosine andbound tryptophan were high as compared with those of non-aromaticamino acids. Discussion is focused upon the interconversionbetween shikimate and quinate, and their roles in the biosynthesisof aromatic amino acids. (Received November 15, 1968; ) 相似文献
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TAMURA TAKEYOSHI; MINAMIKAWA TAKAO; KOSHIBA TOMOKAZU 《Journal of experimental botany》1982,33(6):1332-1339
Acid phosphatase from cotyledons of dark-grown Vigna mungo seedlingswas separated into four forms (la, Ib, Ha and lib) by ion-exchangercolumn chromatographies. Each form of the acid phosphatase wascharacterized for its pH dependency, substrate specificity,thermal stability, activation energy, approximate molecularweight, and the effect of metal ions and other substances onits activity. Each form of the enzyme exhibited high activitytowards ATP and ADP relative to their activity towards p-nitrophenylphosphate,but showed very low activity towards phytate, a major organicphosphate reserve in cotyledons. Among the four forms, lib wasmost distinguishable by its low molecular weight and the thermalenhancement of activity. 相似文献
4.
A study was made of chages in the activities of enzymes relatedto the biosynthesis of aromatic compounds in etiolated mungbean seedlings during their growth. Shikimate: NADP oxidoreductaseactivity in the root-shoot axes increased rapidly to attainits highest activity the 4th day after sowing, and remainedat that level over the experimental period of 7 days. 5-Dehydroquinatehydro-lyase activity continuously increased for at least 7 days.In the cotyledons, a gradual decrease in the activities of theseenzymes occurred. Phenylalanine ammonia-lyase activity in root-shootaxes gradually increased showing a maximum on the 6th day. Thehighest specific activity, on a protein basis, of this enzymewas seen in the initial stage of growth. In the cotyledons,a rise in total activity appeared on the 2nd day. Tyrosine ammonia-lyaseactivity was very low as compared with phenylalanine ammonia-lyase.The enzyme activities of light-germinated seedlings were comparedto those of dark-germinated seedlings on the 7th day. Lighthad practically no significant effect on the appearance of shikimate:NADP oxidoreductase and 5-dehydroquinate hydro-lyase activities.On the other hand, a marked effect from the light on the riseof phenylalanine ammonia-lyase and tyrosine ammonia-lyase activitieswas found, especially in the epicotyl-plumules. The results are discussed with respect to the metabolism ofalicyclic acids such as shikimic acid in the developing mungbean seedlings.
1This work was partly supported by a grant-in-aid from the Ministryof Education. 相似文献
5.
The imposition of the stresses of climate change (higher temperatures and in many regions lower rainfall) on existing stressors, such as habitat loss and degradation, will increase pressures on native fauna already experiencing declines. We focused on assessing how the ‘Big Dry’ (severe drought, 1997–2010) in south‐eastern Australia affected populations of a small marsupial carnivore, the yellow‐footed antechinus (Antechinus flavipes), in box‐ironbark forests, which suffer a range of anthropogenic disturbances. Trapping of the mammal was conducted on 136 (0.25 ha) sites in two box‐ironbark forests in 2004, 2005 and 2011 (46 or 64 sites per year). Capture rates of all distinct individuals, males and second‐year females with suckled teats, and the number of suckled teats were positively associated with rainfall in the previous September (time of lactation and deposition of young in nests). Despite differences between forests in capture rates of all individuals, the positive effect of rainfall was evident in both forests. Populations in one forest, Chiltern, were substantially larger than other locations surveyed in 2004 and 2005, yet crashed to small numbers in 2011. This crash was most likely due to low rainfall in the preceding years including the lowest recorded annual rainfall (2006), below‐average annual rainfall (2007, 2008 and 2009) and well‐below‐average rainfall in September (2006, 2007 and 2008). The predicted drying and warming climate in south‐eastern Australia and habitat loss and degradation pose a threat to the viability of the yellow‐footed antechinus in box‐ironbark forests. An integrated approach to small‐mammal management is necessary given that the region may be facing additional losses, especially during droughts, to those already experienced since the early 1800s. Our work emphasizes the need to identify specific effects of stressors on vital demographic characteristics of species. 相似文献
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SHAUN A. FORGIE SARA L. GOODACRE MARTIN I. TAYLOR BRENT C. EMERSON 《Molecular ecology resources》2006,6(3):820-822
The Canary Island pine weevil Brachyderes rugatus (Wollaston) consists of four allopatric subspecies that are thought to have arisen from several historic colonization events within the archipelago. We have isolated and optimized seven microsatellite loci from Brachyderes rugatus calvus from Gran Canaria. Six of these loci are polymorphic within B. rugatus (11–22 alleles per locus; heterozygosity between 0.43 and 0.84). There is no evidence for heterozygote deficit within populations or for linkage disequilibrium between pairs of loci. These molecular markers are likely to prove useful tools for quantifying the genetic variability of bottlenecked island populations. 相似文献
10.
PETER H. KERR SHAUN L. WINTERTON 《Biological journal of the Linnean Society. Linnean Society of London》2008,93(1):9-13
We provide the first evidence of a small-headed fly planidium (first instar larva; Diptera: Acroceridae) associated with a whirligig mite (Acari: Acariformes: Prostigmata: Anystina: Anystidae) in Baltic amber. This fossil is surprising as parasitic nematodes are the only metazoans known to successfully attack acariform mites, and Acroceridae are believed to be host-restricted parasitoids of spiders. The fossil corroborates a previously published, but widely dismissed, paper that first reported parasitism of parasitengone mites by acrocerid planidia. The possible natural history implications of this find are discussed. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 9–13. 相似文献