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421.
Hisako Urabe Yoko Sugawara Motowo Tsukakoshi Akira Ikegami Hitoshi Iwasaki Takahiro Kasuya 《Biopolymers》1987,26(6):963-971
Low-frequency Raman spectra of the self-associates of guanosine monophosphates (GMPs) Na2 · 5′GMP, K2 · 5′GMP, Na2 · 3′GMP, and K2 · 3′GMP, and polyribonucleic acid K · poly(rG), were obtained. In acidic gels and dried fibers, GMP molecules are known to form helical stacks of hydrogen-bonded tetramers. Some low-frequency collective modes specific to the helically stacked structures were observed. We examined the dependence of these modes on counterions and water content. The lowest frequency mode at ca. 20 cm?1 is sensitive to the water content of the sample and is clearly visible in solid-state samples, so it works as a marker band of the environmental condition of the helices. The intensity and the peak frequency of this mode in solid-state samples depend on the helical structure and counterions. The broad peaks in the vicinity of 100 cm?1 are influenced by cations and are independent of water content. 相似文献
422.
Hybridization and Polyploidization of Saccharomyces cerevisiae Strains by Transformation-Associated Cell Fusion 下载免费PDF全文
Hybrid or polyploid clones of Saccharomyces cerevisiae produced by protoplast fusion were easily isolated by selecting transformants with the plasmid phenotype because the transformation was directly associated with cell fusion. When haploid cells were used as the original strain, the transformants were mostly diploids with a significant fraction of polyploids (triploids or tetraploids). Repeated transformation after curing the plasmid gave rise to clones with higher ploidy, but the frequency of cell fusion was severely reduced as ploidy increased. 相似文献
423.
Hirotaka Shiba Toshiyuki Kawasumi Yasuo Igarashi Tohru Kodama Yasuji Minoda 《Archives of microbiology》1985,141(3):198-203
The incorporation of 14CO2 by the cell suspensions of an extremely thermophilic, aerobic hydrogen-oxidizing bacterium, Hydrogenobacter thermophilus was studied. After short time incubation of the cell suspensions with 14CO2, the radiactivity was initially present in aspartate, glutamate, succinate, phosphorylated compounds, citrate, malate and fumarate. All of these compounds except phosphorylated compounds were related to the members of the tricarboxylic acid cycle. The proportion of labelled aspartate onglutamate in total radioactivity on each chromatogram decreased with incubation time, while the percentage of the radioactivity incorporated in phosphorylated compounds increased with time up to 10 s. These indicated that aspartate and glutamate is derived from primary products of CO2 fixation.In cell-free extracts of Hydrogenobacter thermophilus, the two key enzymes in the Calvin cycle, ribulose-1,5-bisphosphate carboxylase and phosphoribulokinase could not be detected. The key enzymes of the reductive tricarboxylic acid cycle, fumarate reductase and ATP citrate lyase were present. Activities of phosphoenolpyruvate synthetase and pyruvate carboxylase were also detected. The referse reactions (dehydrogenase reactions) of -ketoglutarate synthase and pyruvate synthase could be detected by using methyl viologen as an electron acceptor.These findings strongly suggested that a new type of the reductive tricarboxylic acid cycle operated as the CO2 fixation pathway in Hydrogenobacter thermophilus. 相似文献
424.
Eiiti Kasuya 《Journal of Ethology》1983,1(1-2):34-45
Behavioral catalogues, transition matrices between 2 consecutive behavioral acts, and the frequency distribution of time spent
in each behavioral act were described for queens and workers of a Japanese paper wasp,Polistes chinensis antennalis in the ergonomic stage (the period from the emergence of the first worker to the emergenece of the first reproductive). The
results were; (1) The whole behavior repertoire of queens was completely included in that of workers. Workers oviposited frequently
in queen-right colonies. (2) The proportion of off-nest activities to the number of total acts for workers was higher than
that for queens. The proportion of time spent off the nest in workers was 5 times as high as that in queens. (3) There was
no significant difference in the proportion of number of oviposition to the total number of acts between queens and workers.
The oviposition rate was 0.06 eggs/h for workers and 0.37 eggs/h for queens. Queens made more dominance behavior and workers
more subordinated behavior. Queens made abdomen wagging more frequently than workers. (4) For behavioral acts common in both
queens and workers, the mean duration of a specific act was approximately equal for both. The mean duration of unsuccessful
flesh collection for workers was 3.4 times as longs as that for queens. Workers did not search for flesh in 10.1% of duration
of flesh collections in the field. (5) The pattern of transitions between 2 consecutive behavioral acts in workers was similar
to that in queens. (6) Alien workers approaching a nest with a load were more often accepted by the nest occupants than alien
workers with no load. Alien workers with no load were not accepted as often as a legitimate nestmates with no load. The reproductive
division of labor between queens and workers inP. chinesis antennalis was incomplete. This suggests worker-queen conflict in different reproductive strategies among colony members. Several behaviors
were consistent with the view that they are the behavioral expression of this conflict. 相似文献
425.
426.
Takashi Furuta Motofusa Katayama Hiromi Shibasaki Yasuji Kasuya 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1992,576(2)
A capillary gas chromatographic—mass spectrometric method for the simultaneous determination of stable isotopically labelled l-histidine (l-[3,3-2H2,1′,3′-15N2]histidine, l-His-[M + 4]) and urocanic acid ([3-2H,1′,3′-15N2]urocanic acid, UA-[M + 3]) in human plasma was developed using dl-[2,3,3,5′-2H4,2′-13C,1′,3′-15N2]histidine (dl-His-[M + 7]) and [2,3,5′-2H3,2′-13C,1′,3′-15N2]urocanic acid (UA-[M + 6]) as internal standards. l-Histidine and urocanic acid were derivatized to αN-(trifluoroacetyl)-imN-(ethoxycarbonyl)-l-histidine n-butyl ester and imN-(ethoxycarbonyl)urocanic acid n-butyl ester. Quantification was carried out by selected ion monitoring of the molecular ions of the respective derivatives of l-His-[M + 4], dl-His-[M + 7], UA-[M + 3] and UA-[M + 6]. The sensitivity, specificity, precision and accuracy of the method were demonstrated to be satisfactory for measuring plasma concentrations of l-His-[M + 4] and UA-[M + 3] following administration of trace amounts of l-His-[M + 4] to humans. 相似文献
427.
Eiiti Kasuya 《Ecological Research》1992,7(3):277-281
The influence of female mate preference on the fitness components of offspring was studied in the melon fly,Dacus cucurbitae. Adult flies were allowed to mate under two experimental treatments. In one treatment, 100 females and 100 males were allowed
to mate freely in a cage (cage-mating). In the other treatment, a single female was allowed to mate with a single male in
a small chamber (chamber-mating). Viability in the immature stages was not different between two treatments. The developmental
speed of female offspring in the cage-mating treatment was faster than that in the chamber-mating treatment. The wing length
of offspring of both sex in the cage-mating treatment was also larger than that in the chamber-mating treatment. These results
were considered to support 3-trait handicap models of the evolution of female mate preference. 相似文献
428.
429.
I Takayanagi H Hagiwara K Koike T Hosokawa Y Kasuya 《Canadian journal of physiology and pharmacology》1991,69(8):1243-1245
Effects of the R(+)- and S(-)-isomers of befunolol and carteolol, beta-adrenoceptors with intrinsic sympathomimetic activity, on the rabbit intraocular pressure were tested. The intraocular pressure was decreased by instillation of the R(+)- and S(-)-isomers of befunolol (0.1 and 0.3%) and of carteolol (1.0%) to the eye and attained the minimum level at 60 min. However, 0.3% of the R(+)- and S(-)-isomers of carteolol did not influence the pressure. The corresponding time courses for the intraocular pressure for the R(+)- and S(-)-isomers did not differ, suggesting that in the treatment of glaucoma, the therapeutic advantage of the R(+)-isomers of befunolol and carteolol may be similar to the S(-)-isomers. 相似文献
430.
Reproductive success, copulation success, and mating success were measured for a population of male dragonflies,Orthetrum japonicum. Copulation success explained the greatest variation in reproductive success. The proportion of copulations followed by oviposition
was positively correlated with the number of oviposited eggs per mating. Directional selection on four morphological characters
was estimated. The effect of selection on correlated traits was comparable to that of direct selection. Directional selection
varied between traits and between episodes in a single trait. The probability that the observed directional selection on the
four morphological traits was expected under the condition of the selective neutrality of traits was not smaller than 5%. 相似文献