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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.
The cdc6 mutants of Schizosaccharomyces pombe have been classified as being defective in progression through the G2 phase of the cell cycle. We cloned an S. pombe gene that could complement the temperature-sensitive growth of the cdc6-23 mutant. Unexpectedly, the cloned gene was allelic to pol3, which encodes the catalytic subunit of DNA polymerase δ. Integration mapping confirmed that cdc6 and pol3 are identical. The cdc6-23 mutant carries one amino acid substitution in the conserved N3 region of Pol3.
Received: 17 October 1996 / Accepted: 19 November 1996 相似文献
3.
Genotoxicity of ptaquiloside, a bracken carcinogen, in the hepatocyte primary culture/DNA-repair test 总被引:2,自引:0,他引:2
The genotoxicity of ptaquiloside (PT), recently isolated from bracken fern and shown to be carcinogenic, was examined by means of the hepatocyte primary culture/DNA-repair test. PT elicited clear unscheduled DNA synthesis with a dose-response effect. The result indicates that PT is a genotoxic carcinogen. 相似文献
4.
Eiji Niwa En-Sheng Chen Satoshi Kanoh Teruo Nakayama 《Bioscience, biotechnology, and biochemistry》2013,77(11):3067-3071
The linearity of the stress-strain relationship for food gel is limited to a very narrow range of the strain (usually less than 0.1 as a Cauchy measure). The reason is thought due to the change in cross-sectional area of the gel upon deformation. In this report, the cross-sectional area was approximately corrected of the compressed gel on the assumption that the gel expanded uniformly without changing its volume upon compression. In cases when the initial Young’s modulus was calculated from the thus-corrected area for some food gels, the linearity was increased for a wider range of strain. 相似文献
5.
Hidekatsu Yokoyama Shin-ichi Niwa Kenji Itoh Reiko Mazuka 《Biological cybernetics》1996,75(2):137-140
On the basis of a temporal model of animal behavior we conducted temporal analysis of eye movements in schizophrenic subjects
(n=10) and normal controls (n=10). We found a fractal property in schizophrenic subjects, the fixation time of eye movement during reading ambiguous and
difficult sentences showing a clear inverse power law distribution. An exponential distribution of a nonfractal nature was
found in normal controls.
Received: 21 July 1995/Accepted in revised form: 30 April 1996 相似文献
6.
Glucanase-treatment of yeast cells was shown to increase the glucose fermenting activity, and decrease the sucrose and maltose fermenting activity. Also, lipase–and phospholipase–treatment decreased the fermenting activity on these sugars. However, the effects on the disaccharide fermenting activity could be reversed under various growth conditions of the yeast cells.From these results, structural factors envolved in the transport of fermentable sugars into yeast cells are discussed. 相似文献
7.
8.
Toda Hideshige; Arima Toshiyuki; Takahashi Masayuki; Ichimura Shun-ei 《Journal of plankton research》1987,9(1):51-63
Ingestion, respiration, and molting loss rates were measuredover the 3 29°C range in Neomysis intermedia. Weightspecific rates of these physiological processes ranged from2 to 140% body C day1 for ingestion, from 2 to 15% bodyC day1 for respiration, and from 0.1 to 5% body C day1for molting loss. All weight-specific rates showed a logarithmicdecrease with a logarithmic increase in body weight, and a logarithmicincrease with a linear increase in temperature below 20 or 25°C.The effect of temperature, however, was different between thephysiological rates, with a large temperature dependency foringestion (Q10 = 2.6 3.9) and molting loss (Q10 = 2.9 3.6) and a moderate temperature dependency for respiration(Q10 = 1.9 2.1). Calculated assimilation efficiencychanged with body size, but was constant over the temperaturerange examined. Allocation of assimilated materials varied witha change in temperature, reflecting the different temperaturedependence between physiological processes. It was deduced thatthe strong temperature dependency of the growth rate in N. intermediaobserved in the previous studies resulted from the large temperatureeffect on ingestion and assimilation rates, superimposed bythe different allocation of assimilated materials.
1Present address: Department of Botany, University of Tokyo,Hongo, Tokyo 113, Japan 相似文献
9.
Yasumasa Kunifuji Terumasa Nakamura Masayuki Takasugi 《Biological trace element research》1987,14(3):237-248
Cd induced changes of Zn and Cd distribution in the liver and kidneys were studied in relation to Cd metallothionein (MT)
synthesis. Wistar male rats were given CdCl2 by sc injection of .8, 1.5, and 3.0 mg Cd/kg three times a week for three weeks. Cd levels of liver and kidneys increased
with the increment of Cd dosage and 80–90% of Cd was found in the cytosol. The MT fractions contained 80–89% cytosolic Cd
in the liver and 55–75% Cd in the kidneys. Zn concentrations in the liver increased following Cd administration, But Zn in
the kidneys showed only slight increase. There was a distinct decrease of Cu concentration in the liver of the 3.0 mg group.
In contrast, Cu concentrations in the kidneys increased about three times in the .8 and 1.5 mg Cd groups, but Cu in the 3.0
mg group showed only 1.5 times increase. The changes of these metal concentrations were observed mainly in the cytosol. Non-MT-Cd
in the kidneys was maximum in the 1.5 mg group, but the 3.0 mg group showed significant decrease. In parallel with this decrease
of Cd, Cu and Zn in the kidneys showed similar decrease. When the kidneys are injured, Zn and Cu appear to leak from this
organ. 相似文献
10.
Stone parsley, soybean, sunflower, sweet potato, potato, andadlay cultivated in a Cd2+-containing medium had Cd-bindingcomplexes with molecular weights of about 4,000 in the roottissues. The complexes were similar to the complex previouslyfound in water hyacinth roots in their absorption and CD spectraand their amino acid compositions. The results indicate thewidespread existence of complexes similar to fission yeast Cd-BPlin roots of various plants. (Received June 30, 1986; Accepted December 18, 1986) 相似文献