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N. Fujii N. Tomaru K. Okuyama T. Koike T. Mikami K. Ueda 《Plant Systematics and Evolution》2002,232(1-2):21-33
CpDNA variation in Japanese beech, Fagus crenata (Fagaceae), was studied in 45 populations distributed throughout the species' range. Two cpDNA regions were sequenced: the
non-coding region between the trnL (UAA) 5′exon and trnF (GAA), and the trnK region (including matK). Thirteen distinct cpDNA haplotypes were recognized and each haplotype was found to be geographically structured. Two major
clades (I and II+III) were revealed in phylogenetic analyses among the haplotypes using F. sylvatica as an outgroup. The haplotypes of Clade I were distributed mainly along the Japan Sea side of the Japanese Archipelago, while
those of Clade II+III occurred chiefly along the Pacific Ocean side. Consequently, the distribution of the two major cpDNA
clades suggests that there were two migration routes in the history of F. crenata; one along the Japan Sea and the other along the Pacific Ocean side of the Japanese Islands.
Received March 19, 2001 Accepted November 22, 2001 相似文献
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V L Young C A Gumucio H Lund R McMahon K Ueda L Pidgeon 《Plastic and reconstructive surgery》1992,89(1):70-6; discussion 77-8
Using the monkey model previously developed, we investigated the long-term effects of retrobulbar hematoma-induced retinal ischemia on functional vision and retinal histology. In this experimental model, ischemic periods of up to 120 minutes did not cause permanent visual deficits, as measured by flashed evoked visual potentials. Similarly, retinal histology showed no evidence of ischemic injury. From this we conclude that blindness after blepharoplasty is not due to retrobulbar hematomas alone and that additional predisposing factors are involved. The most likely additional factor is preexisting occult vascular ocular pathology. 相似文献
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Detergent soluble extracts of differentiated regions of the Porphyra perforata J. Ag. thallus (holdfast, rhizoidal, vegetative and reproductive cells) were fractionated on sodium dodecyl sulfate polyacrylamide gels. Glycoproteins were identified by their lectin affinity. Extracts from all areas of the thallus contained glycoproteins, but the staining patterns were different for each region with each of the lectins tested: concanavalin A, Ulex europeaus agglutinin, Ricinus communis agglutinin, soybean agglutinin and peanut agglutinin. These data indicate that the morphologically distinct regions of the thallus also differ biochemically. Analysis of the lectin blots revealed the presence of tissue-specific glycoproteins in the five thallus areas. Such unique glycoproteins could be used as markers of differentiation in this species. 相似文献
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Summary ThePhysarum plasmodium shows rhythmic contractile activities with a period of a few min. Phases of the oscillation in the plasmodium migrating unindirectionally agreed sideways throughout at the frontal part. So, time course of an intracellular chemical component was determined by analyzing small pieces cut off successively from the frontal part of the large plasmodium. Intracellular NAD(P)H concentration oscillated with the same period as the rhythmic contraction but with a different phase advancing about 1/3 of the period. UV irradiation suppressed the rhythmic contraction without affecting the rhythmic variation of NAD(P)H. Thus, the NAD(P)H oscillator works independently of the rhythmic contractile system, but seems entraining with each other.Abbreviations UV
ultraviolet
- NADH
nicotinamide adenine dinucleotide, reduced form
- NADPH
nicotinamide adenine dinucleotide phosphate, reduced form
- ATP
adenosine 5-triphosphate
- cAMP
cyclic adenosine 3, 5-monophosphate
- FMNH2
flavin mononucleotide, reduced form
- TCA
tricarboxylic acid
- BSA
bovine serum albumin
- DTT
dithiothreitol 相似文献