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111.
Hiroshi Ikeda 《Primates; journal of primatology》1982,23(3):338-347
Population changes and home range utilization of the wild Japanese monkey at Mt. Kawaradake have been studied since 1972.
Age compositions of this troop were obtained over a seven-year period. Troop size decreased from over 100 to 40 individuals
as a result of a capture in 1974.
The capture affected directly and indirectly the troop's range and population dynamics. The troop reduced its range size from
4.7 km2 to 2.67 km2 and changed its utilization pattern in relation to the decrease in size. After the capture, the troop used one particular
area intensively, whereas the rhythmic nomadic pattern had been observed as before. This may have been caused by the decrease
in the overall food requirement of the troop.
The birth rate increased significantly after the capture. However, troop size did not increase because of the low recruitment
rate for adult females and the high mortality of juveniles. 相似文献
112.
Tryptensin, a vasopressor substance generated from human plasma protein fraction IV-4 by trypsin, has been isolated and the amino acid composition analysed. The procedures used for the isolation were: (a) adsorption of the formed tryptensin on Dowex 50W (X2; NH4+ form); (b) gel filtration through Sephadex G-25; (c) cation-exchange chromatography on CM-cellulose; (d) anion-exchange chromatography on DEAE-cellulose; (e) re-chromatography on CM-cellulose; (f) gel filtration on Bio-Gel P-2; (g) partition chromatography on high-pressure liquid chromatography. The homogeneity of the isolated tryptensin was confirmed by thin-layer chromatography and thin-layer electrophoresis. The amino acid analysis of the hydrolysate suggested the following proportional composition: Asp, 1; Val, 1; Ile, 1; Tyr, 1; Phe, 1; His, 1; Arg, 1; Pro, 1. This composition is identical with that of human angiotensin. 相似文献
113.
114.
Pathological and microbiological studies were conducted on lesions in the lungs of 194 calves from mass rearing facilities. Macroscopically, the lesions were classified into six forms: nonlesion, atelectasis, mild pneumonia, moderate pneumonia, advanced pneumonia, and advanced pneumonia accompanied with abscess. Histopathological examination revealed bronchopneumonia in most of the calves. Lesions more advanced than moderate pneumonia were complicated with desquamation, severe exudation, and necrosis. Bacteriologically, Pasteurella sp. was isolated often in combination with Staphylococcus sp. from about a half of the atelectatic cases. With the development of pneumonic lesions, Pasteurella sp. was isolated at a high frequency in combination with Haemophilus sp., Streptococcus sp., and Corynebacterium sp. Prominent necrosis was more often seen in cases with Pasteurella haemolytica isolated than in cases with only Pasteurella multocida isolated. Mycoplasma sp. and Ureaplasma sp. were isolated from distinctly pneumonic lesions. Advanced pneumonic lesions were observed in many calves over 30 days of age. The importance of environmental and managerial improvement was also emphasized, since calf pneumonia tended to break out in facilities under unsatisfactory conditions in the present work. 相似文献
115.
When thiamine concentration in subculture medium was rapidlylowered to nil, soybean cells in suspension became necroticand stopped growing entirely. When it was gradually lowered,cell growth was vigorous until the concentration was reducedto 7.8?103 mg/liter. The cells at this level of thiamineceased growing for a time, but prolonged culture in the samemedium resulted in the appearance of fresh white cells whichcould be easily distinguished from the old brown, necrotic cellsin the aggregates. These new cell lines could be subculturedwith further reduction in the thiamine supply, growing as largeraggregates of about 4 mm in diameter. New cell lines were similarly obtained by prolonged culturesin media containing a thiamine precursor; three lines appearedto be habituated to the pyrimidine moiety and one to the thiazolemoiety. The latter cell line could be subcultured without thiamineand its precursors for at least eight passages. These habituatedcells were characterized by the increase of the dry to freshweight ratio and by their growth in large aggregates.
1Present address: Section of Phytochemical Research, Eisai Co.,Ltd., Kawashima, Gifu 483, Japan. (Received December 15, 1978; ) 相似文献
116.
H Takeuchi H Tamura A Kumagai M Ikeda 《Comptes rendus des séances de la Société de biologie et de ses filiales》1979,173(5):980-988
The influences of two water soluble contrast media, meglumine iothalamate and meglumine iocarmate, on the neuronal excitability and on the neuronal sensitivity to putative transmitters were examined in comparison with those of sucrose using two identifiable giant neurones of Achatina fulica Férussac (the TAN and the PON). A relatively low increase of osmotic pressure of the extracellular fluid, produced by the application of contrast media, reversed the Cl- dependent inhibition caused by a putative transmitter. The same increase of this osmotic pressure, however, did not influence the Cl- independent inhibition and the excitation of the neurone examined. The hyperpolarization of neuromembrane was caused by an increase of osmotic pressure of the extracellular fluid. Its relatively high increase was necessary to make spontaneous spike discharges disappear totally. All effects of the two contrast media, observed in this study, were due to the increase of osmotic pressure of the extracellular fluid ; no specific effect of the contrast media containing the iodine on the indicators used was observed. 相似文献
117.
Summary The role of the recA gene product of Escherichia coli in genetic recombination was examined in a system where recombination takes place in the absence of protein synthesis. recA200 bacteria were infected with two mutant strains of phage lambda in the presence of chloramphenicol and rifampin, and the resulting recombinant DNA molecules were measured by in vitro packaging. When recA200 bacteria grown at a temperature that is permissive for RecA phenotype were transferred to a temperature that is restrictive for RecA phenotype in the presence of the inhibitors, recombination of the infecting phages was severely blocked. This result shows that the recombination activity of the recA200 cells is inactivated by the change of temperature even in the absence of protein synthesis. The most likely explanation of this result is that the recA protein is directly involved in the recombination detected in the presence of chloramphenicol and rifampin. 相似文献
118.
Ubiquinone (UQ) formation in BY-2 tobacco cells was especially promoted by a high concentration of 2,4-D. 2,4,5-T, MCP and NAA also promoted UQ formation in these cells. The UQ content in the cells cultured at high concentrations of 2,4-D was higher than that of controls throughout the culture period. The addition of 2,4-D at an early period in cell growth was very effective in promoting UQ formation, but addition at the stationary phase was ineffective. Cell growth was improved by adding phosphate to the medium but UQ content was decreased. UQ content decreased slowly during subculturing, whereas cell growth recovered gradually. 相似文献
119.
Koenig J. H. Ikeda Kazuo 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1983,151(3):295-310
Journal of Comparative Physiology A - Intracellular recordings were made from the motor neurons which innervate the dorsal longitudinal flight muscle (DLM) inDrosophila, while a normal-appearing... 相似文献
120.