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21.
Masao Kawai Kenji Yoshiba Shigeru Ando Shigeru Azuma 《Primates; journal of primatology》1968,9(1-2):1-12
The social behavior pattern of a solitary male at Koshima was studied by means of radio-telemetry. The relationship between the solitary males and the troop was estimated from radio-tracking data of the former's location and movement, and by direct observation of the latter at each corresponding hour.For most of day, the solitary male stayed within a distance of about 20 to 150 m from the central part of the troop, occasionally approaching it. His movement also was synchronized with that of the troop. For two nights, the solitary male slept at places which were about 200 m from the sleeping sites of the troop and faced them across the beach. The relationship between the solitary male and the troop did not seem to be strongly antagonistic.It can be assumed that the solitary male was moving according to certain pre-determined relationships or social contacts with the troop. The example of this solitary male shows the existence of the solitary male that follows and maintains contact with the troop, even outside the copulatory season.This study was sponsored by Scientific Research Grant No. 91620 of the Ministry of Education to the Japan Monkey Centre. 相似文献
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Interconversion of polyamines in wild-type strains and mutants of yeasts and the effects of polyamines on their growth 总被引:1,自引:0,他引:1
Koei Hamana Shigeru Matsuzaki Kohei Hosaka Satoshi Yamashita 《FEMS microbiology letters》1989,61(1-2):231-236
Yeasts of wild-type strains, such as Saccharomyces cerevisiae, Schizosaccharomyces pombe and Candida albicans were shown to have the ability to form aminopropylcadaverine and aminopropylhomospermidine from cadaverine and homospermidine, respectively. A polyamine autotroph S. cerevisiae 179-5, which lacks ornithine decarboxylase, produced both aminopropylcadaverine and aminopropylhomospermidine, while another mutant S. cerevisiae Y 260 A, which lacks spermine synthase, formed only aminopropylcadaverine. Naturally-occurring triamines and tetraamines except norspermidine and norspermine stimulated the growth of S. cerevisiae 179-5. All the six aliphatic diamines with carbon chain length ranging from one to six were effective in activating the growth of S. cerevisiae 179-5, though all of them were not converted to either triamines or tetraamines. 相似文献
24.
Hohzoh Kiyohara Toshiro Watanabe Junko Imai Noboru Takizawa Takashi Hatta Kazutaka Nagao Akira Yamamoto 《Applied microbiology and biotechnology》1990,33(6):671-676
Summary To breed industrially useful strains of a slow-growing, red-pigment-producing strain ofMonascus anka, protoplasts ofM. anka MAK1 (arg) andAspergillus oryzae AOK1 (met, thr) were fused. A mixture of protoplasts prepared from mycelia ofM. anka MAK1 treated with 2% Usukizyme and ofA. oryzae AOK1 treated with 2% Usukizyme and 0.2% NovoZym 234 was incubated with 30% (w/v) polyethylene glycol no. 6000. Heterokaryon fusants complementing the auxotrophies of both mutants were isolated on minimal medium, but segregated into red (MAK1) and white (AOK1) sectors after being cultured on a complete medium. After irradiation with UV light, the fusants gave stable heterozygous diploids that formed long white hyphae. These diploids, which had twice as much DNA in the nucleus as their parents, grew more rapidly than the parent strain YZT1, and produced ethanol earlier than the parents. Production of amylase, protease, and kojic acid by the fusants was intermediate in amount between that of the two parents. 相似文献
25.
Movement of the fluvial form of red-spotted masu salmon (1+ and older),Oncorhynchus masou rhodurus, was studied using mark-recapture methods in a Japanese mountain stream. Most (63–91%) adult salmon were recaptured in the
pool in which they were marked. The rest of the salmon moved upstream or downstream <20m during the non-breeding period. The
proportion of the salmon moving increased slightly during the breeding period, but did not exceed 66%. The distance moved
was also more variable during this period. The proportion of the smaller salmon which moved was larger than that of the larger
fish during the non-breeding period. Conversely, during the breeding period, larger fish moved more frequently. Sedentary
behaviour and local movements of adult salmon seem to be affected by their social relationships. 相似文献
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The potential causes of the variable nature of recruitment of marine organisms can be inferred from the scales over which they vary. Sampling for recruits of Semibalanus cariosus on the intertidal concrete tetrapods at 21 fishing ports along the Kameda Peninsula, southern Hokkaido, Japan, was conducted at the end of the recruitment season in 1994 at three spatial scales: at each fishing port, separated by several km; at two sites at each fishing port, separated by several hundred m; and on three blocks at each site, separated by 1–2 m. At all spatial scales, recruitment intensity was independent of adult densities. Recruitment densities significantly varied within all spatial-scales, however, 85.6% of the total variances was estimated to be due to variation among ports. Such km-scale variation of recruitment intensities coincided with the hydrographic pattern of the direction of coastal current. 相似文献
28.
Hiroyuki Yamaguchi Hitoshi Miura Kazuoki Ohsumi Takako Osaki Haruhiko Taguchi Tomoko Yamamoto Tomoko Hanawa Sachio Ogata Shigeru Kamiya 《Microbiology and immunology》1996,40(1):77-80
To determine amino acid sequences of the epitopes recognized by monoclonal antibodies (mAbs) 3C8 and 5C3 directed against Yersinia enterocolitica heat-shock protein (HSP60), a dot blot analysis was perfomed using synthesized peptides of Y. enterocolitica HSP60 such as peptides p316-342, p327-359, p340-366, p316-326, p316-321, p319-323, and p321-326 which represent positions of amino acids in Y. enterocolitica HSP60. The dot blot analysis revealed that 5C3 mAb reacted with p316-342, p316-326 and p321-326, and 3C8 mAb p316-342 and p316-326. These results indicate that the epitopes recognized by the mAbs were associated with eleven amino acids, Asp Leu Gly Gln Ala Lys Arg Val Val Ile Asn, of p316-326. The sequence homology between p316-326 of Y. enterocolitica HSP60 and the rest of the HSP60 family suggests that the five amino acids of Lys, Arg, Val, Ile and Asn, which are highly conserved in the HSP60 family, might be related with the epitope recognized by 3C8. In contrast, it was also demonstrated that three amino acids of Leu, Gly and Val, which are not well conserved in the HSP60 family, might be related to the epitope recognized by 5C3. 相似文献
29.
Itoh Shigeru; Iwaki Masayo; Tomo Tatsuya; Satoh Kimiyuki 《Plant & cell physiology》1996,37(6):833-839
Transient absorbance changes of the primary electron donor chlorophylla (P680) and acceptor pheophytin a (H) were measured at 77 Kby nanosecond laser spectroscopy in the D1-D2-cytochrome b559photosystem II reaction center complex containing dibromomethylisopropylbenzoquinone (DBMIB). After the laser excitation of the reactioncenter in the presence of DBMIB, only the P680+-(DBMIB-) statewas detected. P680+ mainly decayed with a t1/e of 11 ms. Inthe absence of DBMIB, the excitation produced the P680+H- radicalpair. The radical pair produced the triplet state (P680T) witha t1/e of 50 ns, and P680T then decayed with a t1/e of 2.1 ms.It was concluded that H- was oxidized by DBMIB in a time rangefaster than the detecting time resolution (3.5 ns) even at 77K. The rapid oxidation of H- by DBMIB was also confirmed bythe suppression of delayed fluorescence with a decay t1/e of50 ns. The P680+(DBMIB-)/P680(DBMIB) difference spectrum exhibiteda Qy, band with a peak at 682 nm with a shoulder at 673 nm.The spectral shape was almost temperature insensitive between77 and 265 K. The feature of this spectrum in the wavelengthrange between 330 and 720 nm was compared with that of P680T/P680or H-/H at 77 K. (Received May 8, 1996; Accepted June 24, 1996) 相似文献
30.