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1.
Masayuki Nakamichi 《Primates; journal of primatology》1984,25(2):192-203
Fourteen female Japanese monkeys of the Arashiyama-B group ranging in age from 11 to 29 years were observed to elucidate the
behavioral characteristics of aging monkeys. A positive significant correlation was found between the occurrences of rest
and age, and a negative significant correlation between the occurrences of auto-grooming and age. Younger female monkeys tended
to be in contact with or in proximity to group members, while older female monkeys tended to spend much more time alone. As
for the grooming interactions, younger female monkeys more often groomed others than did older female monkeys. Also, the former
engaged in grooming more frequently than in being groomed, while the latter spent more time in being groomed than in grooming.
The old female monkeys showed no marked decline in rank, but some of them were surpassed by their adult daughters. 相似文献
2.
Echolocation sounds and hearing of the greater Japanese horseshoe bat (Rhinolophus ferrumequinum nippon) 总被引:1,自引:0,他引:1
Ikuo Taniguchi 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1985,156(2):185-188
Summary The relationship between the orientation sounds and hearing sensitivity in the greater Japanese horseshoe bat,Rhinolophus ferrumequinum nippon was studied.An orientation pulse consisted of a constant frequency (CF) component followed by a short downward frequency-modulated (FM) component. Sometimes, an initial upward FM component preceded the CF component. Duration of pulses was about 30 ms and the CF of resting pulses (RF) averaged 65.5 kHz. The best frequency (BF) at the lowest threshold in audiograms as measured by the pinna reflex averaged 66.1 kHz. Audiograms showed remarkable sharp cut-offs on both sides near the BF. The frequency difference between the BF and the RF was about 0.6 kHz, and the RF was always below the BF. The values of RF and BF were characteristically different from those of the European subspecies,Rhinolophus ferrumequinum ferrumequinum.Abbreviations
BF
best frequency
-
CF
constant frequency
-
FM
frequency modulated
-
RF
resting frequency 相似文献
3.
4.
To reveal the difference of molecular property between structurallysimilar odorless and odoriferous musk compounds, 10 pairs ofbenzenoids (monocyclic-, dicyclic- and tricyclic-) were examined.Molecular structures of all compounds were optimized by MNDO(modified neglect of diatomic differential overlap) consideringconformation. Parameters effective in discriminating two groups,group A of 10 odorless compounds and group B of 10 musk odorcompounds, were searched from 34 candidate parameters by adaptiveleast squares. The best three parameters found were log P value(octanol/water partition coefficient), the longest side lengthof hexahedron circumscribing a molecule, and the parameter whichexpresses structural hindrance to the functional group whena molecule approaches the receptor site. The two groups of compoundswere completely discriminated using these three parameters. 相似文献
5.
Kunihiko Mitsuo Takuro Kobayashi Nobue Shinnoh Ikuo Goto 《Neurochemical research》1989,14(12):1191-1194
The in vivo metabolism of galactosylceramide (gal-cer) in normal mice and in twitcher mice, a model of human GLD, was examined following intracerebral administration of gal-cer containing [1-14C]stearic acid. In normal mice, gal-cer was hydrolyzed to ceramide within 6 hours and ceramide was hydrolyzed to sphingosine and fatty acid. Most of the released fatty acid was immediately incorporated into other lipids. About 75% of injected gal-cer was hydrolyzed 80 hours after the injection, while in the twitcher mouse, only 17% of gal-cer was hydrolyzed. These results show that degradation of gal-cer is impaired in the twitcher mouse brain, but contradict to the fact that there was no evidence of any accumulation of gal-cer in the brain. This discrepancy may be due to the different sorting routes of biosynthesized and exogenously-administered gal-cer in the mouse brain. Most of the biosynthesized gal-cer is incorporated into myelin, while the injected gal-cer is incorporated into lysosomes. 相似文献
6.
ADP-Ribosylation of Histones in Nuclei Isolated from Embryos of the Sea Urchin, Hemicentrotus pulcherrimus 总被引:1,自引:1,他引:0
Shigehisa Furuya Yasuyuki Kamata Ikuo Yasumasu 《Development, growth & differentiation》1994,36(1):103-110
Two-dimensional electrophoresis (2D-PAGE) of a histone fraction isolated from nuclei of embryos of the sea urchin Hemicentrotus pulcherrimus exhibited almost all histone species at all stages examined. At the gastrula stage, a spot of H1A became evident and three spots closely associated with one another were found in place of a single spot of H2A.1. In the histone fraction isolated from [adenylate-32 P] NAD+ -treated nuclei of all stages examined, autoradiograms of 2D-PAGE exhibited spots of mono [ADP-ribosyl] ated H1 and polymodified H2B.2, H3.1, H3.3 and H4 but did not show ADP-ribosylated H2A.1, H2A.2 or H2B.1. Poly [ADP-ribosyl] ated H3.2, found in morulae, was not detectable in blastulae and gastrulae. Treatment with dimethylsulfate, known to activate ADP-ribosylation in other cell types, induced poly [ADP-ribosyl] ation of H2A.2 and H2B.1 in embryos at all stages examined, and also polymodification of H3.2 in gastrulae. ADP-ribosylation of H1, H2B.2, H3.1 and H3.3 was hardly affected by dimethylsulfate treatment, though modification of H4 was blocked by this treatment. Probably, strong regulation of ADP-ribosyltransferase reactions causes failures of modification of H2A.2 and H2B.1 throughout early development and also of H3.2 at the gastrula stage. Regulation of histone ADP-ribosylation is thought to alter chromatin structures and the rate of gene expression, contributing to cell differentiation. 相似文献
7.
Takeo Yoshimura Takuro Kobayashi Shuichiro Goda Ikuo Goto 《Neurochemical research》1994,19(6):735-741
The repetitive passages of a Schwann cell culture results in the appearance of immortalized cells. In order to investigate the direct effects of cyclic AMP (cAMP) on Schwann cell proliferation, we used the immortalized Schwann cells because the responses of a short-term Schwann cell culture to agents increasing the intracellular cAMP are more complicated and it does not seem that all of them are due to the direct effects of cAMP. By adding up to 200 M of forskolin, an adenylate cyclase activator, to the culture medium, Schwann cell proliferation was inhibited and the intracellular 1,2-diacylglycerol (DG) level was decreased in a dose-dependent manner to 44 and 53% of the control values, respectively. The protein phosphorylation activity in the cytosol from the cell treated with 100 M forskolin, assayed with myelin basic protein as the acceptor, decreased to 78% and this inhibition was then reversed by the addition of 1-oleoyl-2-acetyl-sn-glycerol (OAG), a membrane-permeable DG, to the assay mixture. The cell proliferation inhibited by forskolin was also restored by the addition of OAG. These data suggest that cAMP inhibits both the activity of protein kinase C (PKC) and consequently cell proliferation through suppression of intracellular DG level, an activator of PKC. Since the inositol 1,4,5-triphosphate level and the hydrolysis of phosphatidylcholine to DG and phosphorylcholine were not affected, forskolin therefore appears to suppress the de novo synthesis of DG. 相似文献
8.
Koiwai Keiichiro Kondo Hidehiro Hirono Ikuo 《Marine biotechnology (New York, N.Y.)》2023,25(3):488-502
Marine Biotechnology - The classification of cells in non-model organisms has lagged behind the classification of cells in model organisms that have established cluster of differentiation marker... 相似文献
9.
Takashi Aoki Ikuo Hirono Teresa de Castro Tadatoshi Kitao 《Zeitschrift fur angewandte Ichthyologie》1989,5(2):67-73
A 562 base pair fragment of DNA from a serotype A strain of Vibrio anguillarum was cloned into pUC9 and used as a hybridization probe for the rapid identification of Vibrio anguillarum by colony hybridization. The probe was tested on nine different fish pathogens, 15 Vibrio isolates, 2 organisms closely related to Vibrio, and 9 serotypes of V. anguillarum. The probe hybridized only with the DNA of V. anguillarum serotypes A and H. The sequence of the 562 nucleotides have been determined. This probe allows rapid, reliable, and specific detection of V. anguillarum in freshwater ayu, Plecoglossus altivelis. 相似文献
10.
Takeshi Sagara Hiromu Egashira Mikako Okamura Ikuo Fujii Yasuyuki Shimohigashi Ken Kanematsu 《Bioorganic & medicinal chemistry》1996,4(12):2151-2166
For three-dimensional understanding of the mechanisms that control potency and selectivity of the ligand binding at the atomic level, we have analysed opioid receptor-ligand interaction based on the receptor's 3D model. As a first step, we have constructed molecular models for the multiple opioid receptor subtypes using bacteriorhodopsin as a template. The S-activated dihydromorphine derivatives should serve as powerful tools in mapping the three-dimensional structure of the μ opioid receptor, including the nature of the agonist-mediated conformational change that permits G protein-coupling to ‘second messenger’ effector molecules, and in identifying specific ligand-binding contacts with the μ opioid receptor. The analyses of the interactions of some opioid ligands with the predicted ligand binding sites are consistent with the results of the affinity labeling experiments. 相似文献