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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.
Two species of fiddler crab, Uca tetragonon(Herbst, 1790) and Uca vocans(Linnaeus, 1758), which belong to the subgenus Gelasimus, dwell on rocky shores and muddy–sandy tidal flats, respectively, in Phuket Is., Thailand. We investigated their feeding ecology in relation to the morphology of their feeding organs: minor food-handling chelipeds and maxillipeds. U. tetragononfed chiefly on rocks covered by filamentous green algae. U. vocansfed on the emerged sand and in shallow water along the shoreline and in pools. While feeding, both crabs made sand pellets beneath their mouthparts and discarded them, indicating that they divided the matter scooped up with their minor chelipeds into edible and inedible fractions by using the maxillipeds in the water passing through their buccal cavity. The morphology of maxillipeds hardly differed between the two species, which means that both species are flotation-feeders. The morphology of their minor chelipeds, however, differed: the tips of the dactyl and pollex were flat in U. tetragononand pointed in U. vocans.When the minor cheliped was closed, U. tetragononhad a hemispherical space in the distal one-fourth of the gape, which was closed by the framing keratin layers and a few setae of the dactyl and pollex. On the other hand, U. vocanshad an ellipsoidal space in the distal half of the gape. We consider these morphological characters to be adaptations to the different feeding substrates for retaining more food-laden sediment. We discuss the role of the setae on the minor chelipeds on the basis of the morphological differences between populations of U. tetragononin Phuket Is. and East Africa where the crab inhabits muddy–sandy tidal flats. 相似文献
4.
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
5.
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
6.
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
7.
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
8.
The genus Avena contains five different chloroplast genomes, I-V. A physical map of chloroplast (ct) DNA of Avena sativa (type I chloroplast genome) was constructed using three restriction endonucleases, PstI, SalI and SmaI. This genome is ca. 135.5 kbp in size, and contains two inverted repeats of ca. 22.5 kbp each, separated by a large (ca. 79.0 kbp) and small (ca. 12.5 kbp) single copy region. The rbcL gene which codes for the large subunit of ribulose 1,5-bisphosphate carboxylase, was located in the map. Restriction fragment patterns of all five chloroplast genomes were compared, and among them five fragment size and five restriction site mutations were disclosed. Four site mutations were found in two or more chloroplast genomes, the other site and five fragment size mutations were specific to one or another of the chloroplast genomes. A dendrogram showing phylogenetic relationships among the five chloroplast genomes, based on the distribution of the common and specific mutations among them, indicates that chloroplast genome divergence characterized by three restriction site mutations occurred first between two diploid groups, each carrying A and C genome (nuclear), respectively, followed by further speciation in each group. 相似文献
9.
Masayuki Sasaki Kenji Sugio Jun-Ichi Soejima Tatsuro Ikeuchi Akira Tonomura Takeo Iwama Joji Utsunomiya Takehiko Sasazuki 《Human genetics》1987,77(1):36-39
Summary We investigated possible association of and linkage between HLA and familial polyposis coli (FPC). In 182 individuals from 66 pedigrees of FPC and 108 individuals from a normal population, HLA-A,-B, and-C antigens were determined. When the frequencies of HLA antigens in 66 unrelated patients and in normal controls were compared, no association of FPC with HLA was observed. For the linkage analysis, HLA haplotypes of 17 affected sib pairs were investigated by the affected sib pair method. The number of pairs which shared two, one, and no haplotypes identical by descent was not significantly different from the number expected with random occurrence (P>0.95). Finally, seven families were analyzed using Morton's sequential test. A maximum lod score of-0.056 at a recombination fraction of 0.4, and a lod of-3.089 at a recombination fraction of 0.05 were obtained. Therefore, there is neither an association of nor linkage between FPC and HLA. 相似文献
10.
cAMP in Anabaena cylindrica: Rapid Changes in Cellular Levels in Response to Changes in Extracellular Environments 总被引:2,自引:0,他引:2
The cellular level of cyclic 3',5'-AMP (cAMP) in the cyanobacteriumAnabaena cylindrica changed transiently in response to changesin extracellular environments. When the cells were transferedfrom dark to light, or anaerobic to aerobic conditions in thedark, the cAMP level rapidly decreased within one min and thengradually recovered. Addition of carbonyl cyanide m-chlorophenylhydrazone(CCCP) which inhibits ATP synthesis caused an increase in cAMPlevel in the light but not in the dark. The level of cAMP increasedseveral fold by lowering the pH from 8 to 6. On the contrary,a rise of pH from 6 to 8 caused a decrease in the cAMP level.It is suggested that the change in membrane electrochemicalpotential is involved in the regulation of cellular cAMP concentration. (Received January 27, 1989; Accepted June 19, 1989) 相似文献