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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.
4.
Effects of fat content in the diet on rat liver peroxisomes was examined. In the livers of rats fed for one week on the high-fat diet containing 30% fat, the cyanide-insensitive palmitoyl-CoA oxidation was accelerated to eight times that of control and the enzymic activities of catalase, carnitine acetyltransferase and carnitine palmitoyltransferase were elevated by the factors of 1.3, 5 and 2, respectively. In contrast, the activities of D-amino acid oxidase in addition to the three enzymes mentioned above were all lowered by 20% when the animals were maintained on a fat-free diet for the same period of time. It appears that the high-fat diet-induced increase in the activity of carnitine palmitoyltransferase is a result of the raised activity of this enzyme in mitochondria only while the apparent high activity reflects stimulation of carnitine acetyltransferase in all the subcellular fractions. Another notable effect of the high-fat diet was a remarkable increase in the quantity of a peroxisome-associated polypeptide which was separable by sodium dodecyl sulfate polyacrylamide gel electrophoresis. It is noteworthy that this effect of the high-fat diet resemble that of clofibrate. If the diet was deprived of fat, however, this polypeptide species, with an estimated molecular weight of 80 000, decreased to a level slightly lower than normal. On the basis of the electron micrographic criteria, the high-fat diet provoked a marked proliferation of hepatic peroxisomes. 相似文献
5.
6.
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
7.
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
8.
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
9.
Resting spore formation during short time-scale upwelling and its significance were investigated in the field and by a simple
theoretical model. Field observations of spore formation ofLeptocylindrus danicus were made off Izu Peninsula, Japan. A rapid increase in ratio of resting spore to vegetative cell numbers indicated thatL. danicus formed resting spores quickly as a response to nutrient depletion in the upwelled water, although only a very low number
of resting spores was found in the upwelling. A simple model was constructed to investigate the possible advantages of spore
formation during short time-scale upwelling. This showed that there is a critical time-scale for resting spore formation to
be advantageous. The nutrient depletion period of the upwelling off Izu was shorter than the critical time-scale determined
by the model. Rapid-sinking of resting spores may increase further the critical time-scale, unless spores return with upwelling
water. For short time-scale upwelling, the vegetative cell may be better suited than the resting spore for enduring a short
period of nutrient depletion.
Contribution from Shimoda Marine Research Center, University of Tsukuba, No. 475. 相似文献
10.
Interaction between cytochrome c and cytochrome c peroxidase: excited-state reactions of zinc- and tin-substituted derivatives 总被引:2,自引:0,他引:2
The effect of cytochrome c peroxidase (CCP) and apoCCP on the fluorescence and phosphorescence of Zn and Sn cytochrome c (cyt c) and the effect of cyt c on the fluorescence and phosphorescence of Zn CCP were examined. We found the following: The fluorescence yields of Zn and Sn cyt c were quenched by about 20% by CCP, consistent with energy transfer between the two chromophores with a separation of about 1.8 nm. The phosphorescence spectrum of Zn cyt c (but not Sn cyt c) shifts by 20 nm to the blue upon complexation with either CCP or apoCCP; at the same time the phosphorescence lifetime of Zn cyt c decreases from 12 +/- 2 to 6 ms with apoCCP addition. Zn CCP phosphorescence decay increases from 8.3 to 9.1 ms upon addition of poly(L-lysine) used to mimic cyt c. It is concluded from these results that binding of the redox partner or an analogue to Zn CCP and Zn cyt c results in a conformational change. The respective phosphorescence lifetimes of Zn and Sn cyt c were 13 and 3 ms in the absence of CCP and 1.6 and 1.1 ms in the presence of CCP; this corresponds to a quenching rate due to CCP of 519 and 570 s-1, for Zn and Sn cyt c, respectively. The phosphorescence of Zn CCP is also affected by native cyt c but is dramatically less than the complementary pair; the quenching rate constant is 17 s-1.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献