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21.
Francisco Yegres Nicole Richard-Yegres Kazuko Nishimura Makoto Miyaji 《Mycopathologia》1991,114(2):71-76
Three strains of Cladosporium carrionii, two human isolates and one from a xerophilous plant, were used to study the effect of culture conditions in 106 newborn ddY mice. Growth in a complex medium (YPG) and a basal synthetic medium (BSM) was compared. Filamentous forms developed during static incubation while conidia were readily formed with shaking. Mice inoculated intraperitoneally were sacrified and autopsied after 4 weeks. Mortality was related only to sporulated exponential phase growing cells. Invasiveness ability was preserved in all experimental conditions. BSM medium that inhibited exopigment formation appeared more suitable than YPG to obtain intact cells for further studies.Biochemical and physiological alteration associated with shape changes during differentiation of vegetative cells into spores could play an important role in virulence of C. carrionii 相似文献
22.
Tatsuhide Kunishita Takeshi Tabira Hidehiko Umezawa Makoto Mizutani Yasutomi Katsuie 《Journal of neurochemistry》1986,46(1):105-111
Biochemical and morphological studies were done on a new trembling mutant hamster CBB. The yield of myelin from the mutant was 30 and 40% of the control at 46 and 140 days of age, respectively, but myelin composition and 2',3'-cyclic nucleotide-3'-phosphohydrolase (CNPase) activity were normal. Morphologically, about 18% of the axons were myelinated in the mutant optic nerve at 46 days of age, in which the myelinated fibers were those with larger diameters (more than 0.6 micron), while the control had a peak at 0.4 micron in diameter. The ultrastructure and thickness of compact myelin lamellae in the mutant were normal. Myelination and the structure of peripheral nerve myelin appeared normal. The results indicate that the essential defect is the delay and arrest of myelination in the CNS, which is probably caused by either a decreased rate of synthesis of myelin components in oligodendrocytes or a defect in the oligodendrocyte-axon recognition in smaller axons. 相似文献
23.
(6R)-Tetrahydrobiopterin Increases the Activity of Tryptophan Hydroxylase in Rat Raphe Slices 总被引:2,自引:2,他引:0
Makoto Sawada Takashi Sugimoto Sadao Matsuura Toshiharu Nagatsu† 《Journal of neurochemistry》1986,47(5):1544-1547
The effects of (6R)- and (6S)-tetrahydrobiopterin (BPH4), tetrahydroneopterin, and 6-methyltetrahydropterin on the activity of tryptophan hydroxylase were investigated in rat raphe slices. The activity of tryptophan hydroxylase was estimated by measurement of 5-hydroxytryptophan (5-HTP) formation under inhibition of aromatic L-amino acid decarboxylase with use of HPLC-fluorometric detection. (6R)-BPH4 (the naturally occurring form) at 42 microM, tetrahydroneopterin at 50 microM, and 6-methyltetrahydropterin at 100 microM increased tryptophan hydroxylase activity to 350, 145, and 146% of control values, respectively. (6S)-BPH4, however, had no significant effects on tryptophan hydroxylase activity. These results suggest that tryptophan hydroxylase is subsaturating in vivo for the naturally occurring cofactor, (6R)-BPH4, and that the concentration of (6R)-BPH4 may play an important role for the regulation of tryptophan hydroxylase activity in vivo. 相似文献
24.
25.
Makoto Daimon Ken-ichi Tsutsumi Jun-ichi Sato Reiko Tsutsumi Kiichi Ishikawa 《Biochemical and biophysical research communications》1984,124(2):337-343
The expression of aldolase A and B mRNAs during azo-dye-induced carcinogenesis in rat liver was examined. After feeding the dye for 18 weeks, the level of aldolase A mRNA increased to about 11 times that in a normal liver, with the concomitant decrease of aldolase B mRNA level to about 25% of that in a normal liver. These changes did not occur progressively during the carcinogenesis, but occurred as an additional phase after 4 week-feeding of the azo-dye. At this stage, the levels of aldolase A and B mRNAs were about 7 times and 45% of that in a normal liver, respectively. This biphasic pattern in the aldolase isozyme expression in the azo-dye-fed rat liver is discussed together with the kinetic data of the enzyme activity. 相似文献
26.
Cycling of soil carbon in the first year after a clear-felling was compared with that before the felling in a Japanese red
pine forest in Hiroshima Prefecture, west Japan. The daily mean temperature at the soil surface in summer was increased after
the felling in comparison to that before felling, and the water content of both the A0 layer and the surface mineral soil was decreased due to the loss of the forest canopy. The rate of weight loss of the A0 layer was reduced after felling. However, accumulation of the A0 layer rapidly decreased because of the lack of litter supply to the forest floor. Low soil respiration after felling was
mainly caused by the cessation of root respiration. Analysis of annual soil carbon cycling was then conducted using a compartment
model. The relative decomposition rate of the A0 layer decreased whereas that of humus and dead roots in mineral soil increased to some extent after felling. The accumulation
of carbon in mineral soil, however, increased slightly due to the supply of humus from roots killed by the felling. 相似文献
27.
Five species including two new species,Araucarioxylon kiiense Ogura,Taxodioxylon albertense (Penhal.) Shimakura,Cupressinoxylon cryptomerioides Stopes,Xenoxylon watarianum sp. nov. andCedroxylon shimakurae sp. nov., were described from the Upper Cretaceous (Late Turonian-Santonian) of southern Saghalien.
Consecutive number from the previous paper (Nishida and Nishida, 1985).
Contributions from the Laboratory of Phylogenetic Botany, Chiba University No. 100. Supported by a Grant-in-Aid for Scientific
Research from the Ministry of Education, Science and Culture No. 59540441. 相似文献
28.
Makoto Hayashi Kazuko Fukushima Akihide Kitamura 《Chemistry and physics of lipids》1983,33(3):233-239
Krafft points of diacylglycerophosphocholines (PC) were measured in alkanes-cyclohexane solutions by differential scanning calorimetry, and it was found that they were regularly increased following the increase in alkane content in the solutions and the chain length of the alkanes. From these results it was deduced that the mixing of PC with alkanes occurred in the gel state of the PC, but not in micelles at higher temperatures above the Krafft points. where micellar solutions are provided. The penetration of alkanes into gel state PC was found to be dominated by Langmuir type interaction, and the affinity of alkanes increases with increasing in chain lengths. Above the Krafft points, the micelle formation was confirmed by using the fluorescence probe technique. 相似文献
29.
Makoto Nagoshi 《Population Ecology》1966,8(1):20-36
- In order to get the knowledge on the age composition of “isaza” population in Lake Biwa and the effect of population density on growth, monthly distribution of mean body length and mean body weight has been analyzed on the basis of monthly haul by “isazabiki” trawl during 1949 to 1953 and also 1960 to 1965.
- There is no apparent sex difference in the growth in the first and second years of life.
- “Isaza” population is composed of two age groups, age 0 and 1 groups (1+fish), the latter occupying by far the greater part in commercial catch.
- During the growth season fishes of both ages feed mainly on zooplankton, though in winter frequently take chironomid larvae, gammaridae and others in volume.
- The growth season falls in the period from April to October in both age groups.
- A considerable yearly variation occurring in growth is in close connection with the fluctuation of population density of all ages.
- The influence affected by the density of age 1 group is larger than that by age 0 group.
30.
Makoto Endo 《Ichthyological Research》1989,36(3):346-349
Glomerular vasculature was investigated in the carpCyprinus carpio, the scorpionfishSebastiscus marmoratus, and the marine catfishPlotosus lineatus with the resin-replica method. An afferent arteriole was connected with a glomerulus in every fish. It was slender in the
carp, whereas the scorpionfish and marine catfish possessed thick afferent arterioles. The glomerular capillaries were sinusoidal.
The divergences, convergences, and windings of these capillaries were not well developed in any of the fish. The glomerular
capillaries converged into an efferent arteriole in the carp and scorpionfish. In the marine catfish, on the other hand, most
of the glomeruli had two efferent arterioles. 相似文献