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51.
Fossil wood assemblages deposited during 6.300–3.000 yBP, are studied at the Akayama Site, central Japan. Layer III containing
fossil woods was divided into three subunits according to intercalating tephras, and total 3618 fossil woods were studied.
In the composition, deciduous broad-leaved trees dominated, accompanied by some evergreen conifers. In the diameter distribution,
nine taxa accounted for nearly 90% of individuals exceeding 10 cm in diameter. Spatial distribution of nine major and three
minor taxa and that of thick individuals clarified the following points: 1)Fraxinus established a lowland forest during 5,000–4,500 yBP, accompanied byAlnus sect.Gymnothyrsus, Acer andAesculus turbinata; 2) small trees ofAlnus sect.Gymnothyrsus extensively intermingled in the lowlandFraxinus forest during 4,500–3,000 yBP; 3)Quercus sect.Prinus and Castanea crenata constituted escarpment forests during 6,300–3,000 yBP; 4)Carpinus sect.Eucarpinus became a major component during 5,000–4,500 yBP, andOstrya japonica replacedCastanea crenata during 4,500–3,000 yBP. Comparison with the other five contemporaneous fossil wood assemblages shows prevalence ofFraxinus-dominant forests during the Late to Latest Jomon Periods in the southern part of the Kanto Plain. 相似文献
52.
Summary The hybrid produced between a Carbondale haploid strain (-methyl-glucoside rapid fermenter) and a haploid strain (non-fermenter), derived from a hybrid between a homothallic and a heterothallicSaccharomyces, showed an irregular segregation pattern with regard to the fermentation of this sugar.To explain this irregularity, three pairs of alleles,MG
1/mg
1,MG
2/mg
2 andMG
3/mg
3, were assumed to be in quantitative control of the fermetation. Haploid cultures carrying the genotypes (1)mg
1
mg
2
mg
3, (2)MG
1
mg
2
mg
3, (3)mg
1
MG
2
mg
3, (4)mg
1
mg
2
MG
3, (5)MG
1
MG
2
mg
3, (6)MG
1
mg
2
MG
3, (7)mg
1
MG
2
MG
3, and (8)MG
1
MG
2
MG
3, were actually recovered. Strains equipped with: either (1) or (2); either (4) or (6); (3); (5); (7); or (8) are non-fermenters, extremely-slow-fermenters, slow-fermenters, medium-fermenters, semi-rapid-fermenters and rapid-fermenters respectively.The role of these genes in sugar fermentation and the identity or nonidentity of some of these genes with maltose and sucrose genes was discussed.With 2 Figures in the Text 相似文献
53.
54.
Nishijima K Hisatsune T Kato H Kohyama M Kakehi M Hachimura S Kaminogawa S 《Cytotechnology》1997,25(1-3):89-100
Feeding of a whole casein diet, which abolished the αs1-casein-specific proliferation and IFN-γ productivity of CD4+ T cells, did not affect the proliferative response of CD8+ T cells with regard to the antigen dose response, cell dose response, kinetics of the proliferation and epitope specificity,
as well as IFN-γ production. To assess the characteristics of the CD8+ T cells, we established αs1-casein-specific CD8+ T cell clones from both casein-fed and control mice. The established clones produced different amount of IFN-γ and IL-10,
and one clone derived from the casein-fed mice produced a remarkable amount of IL-10. The clones from casein-fed mice produced
considerable amounts of TGF-β, while those from control mice produced only small amounts. The possible role of CD8+ T cells in oral tolerance is discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
55.
56.
It was previously reported thatHistoplasma capsulatum (Hc) yeast not only failed to stimulate a murine macrophage oxidative burst (OB), but they also blunted or abolished OB stimulation by a subsequent encounter with potent stimuli such as zymosan or phorbol 12-myristate 13-acetate (PMA). The present studies show that macrophage deactivation is proportional to the time of incubation and the dose of Hc yeast that induce the deactivated state. Hc yeast derived from a virulent strain (G217B) are more efficient inducers of macrophage deactivation than similar preparations derived from the avirulent Downs Hc strain. Yeast cells of two other pathogenic fungi,Candida albicans andCryptococcus neoformans are shown to stimulate rather than deactivate a macrophage OB. 相似文献
57.
Methionine sulfoximine (MSO) greatly reduced the carbon dioxideexchange rate (CER) of detached wheat (Triticum aestivvm L.cv Roland) leaves in 21% O2, but only slightly reduced it in2% O2. A supply of 50 mM NH4Cl had little effect on the CERirrespective of the O2 concentration. A simultaneous additionof glutamine and MSO protected against the inhibition of photosynthesisto a considerable extent and caused the accumulation of moreNH3 than did the addition of MSO alone. Fixation of 14CO2 in wheat leaves was inhibited by MSO treatmentin 22% O2, and there was decreased incorporation of 14G intoamino acids and sugars and increased label into acid fractions.The addition of MSO and glutamine together eliminated the effectof MSO on the photosynthetic 14CO2 fixation pattern. NH4Cl stimulatedthe synthesis of amino acids from 14CO2, especially the synthesisof serine in 22% O2. Our observations show that factors other than the uncouplingof photophosphorylation by accumulated NH3 may be responsiblefor the early stage of photosynthesis inhibition by MSO underphotorespiratory conditions.
1Present address: Department of Agricultural Chemistry, KyushuUniversity, Fukuoka 812 Japan.
2Also at U.S. Department of Agriculture, Agricultural ResearchService, Urbana, Illionois 61801, U.S.A. (Received September 13, 1983; Accepted February 2, 1984) 相似文献
58.
Thyroglobulin-like immunoreactivity of the parafollicular cells was studied by an immunoperoxidase bridge technique using antisera against dog thyroglobulin fragments. 1. The dog parafollicular cells were specifically stained by anti-peak I (27S and larger components fraction) antiserum absorbed with peak II (19S fraction). By this method, they were easily distinguishable from the non-reactive follicular cells and colloid droplets. More sensitive staining of the parafollicular cells was possible with anti-peak I' (larger components fraction) antiserum. The staining reactions indicated that the antigenic material responsible for immunoreactivity of the parafollicular cells was due to larger molecular components of thyroglobulin corresponding to 32S, 37S or greater than 37S, and was not due to either the 19S thyroglobulin or to the 27S iodoprotein. 2. A conspicuous decrease of the immunoreactive material in the parafollicular cells occurred in the dog after both chronically induced hypercalcemia and antithyroid drug treatment. This coincided with movement of secretory granules containing calcitonin as shown by staining with silver impregnation, HCl-basic dye, and lead-hematoxylin. 3. The antisera against larger molecular components of dog thyroglobulin showed a high degree of cross-reactivity to the parafollicular cells of most of the mammalian species investigated; rats, rabbits, hamsters, mice, cats, lions, goats, cows, and human. 相似文献
59.
60.
Hiroshi Ikeda 《Primates; journal of primatology》1982,23(3):338-347
Population changes and home range utilization of the wild Japanese monkey at Mt. Kawaradake have been studied since 1972.
Age compositions of this troop were obtained over a seven-year period. Troop size decreased from over 100 to 40 individuals
as a result of a capture in 1974.
The capture affected directly and indirectly the troop's range and population dynamics. The troop reduced its range size from
4.7 km2 to 2.67 km2 and changed its utilization pattern in relation to the decrease in size. After the capture, the troop used one particular
area intensively, whereas the rhythmic nomadic pattern had been observed as before. This may have been caused by the decrease
in the overall food requirement of the troop.
The birth rate increased significantly after the capture. However, troop size did not increase because of the low recruitment
rate for adult females and the high mortality of juveniles. 相似文献