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41.
Genetic variability in individual troops of the Japanese macaque (Macaca fuscata fuscata) was quantified by the proportion of polymorphic loci and the average heterozygosity per individual from the results of starch-gel electrophoreses of blood proteins controlled by 32 independent genetic loci. The former averaged 9.2% and the latter 1.3%, the values being remarkably lower than those estimated for other animal populations. Geographical distribution of the genetic variations was not uniform in the whole species but the variants occurred only in limited areas. Assuming the selective neutrality of segregating alleles and the two-dimensional stepping-stone model of population structure, the genetic migration rate between the local demes per generation could be estimated to average less than inverse of average effective deme size. Here, the local deme is not a troop itself, but it consists of several troops tightly connected with each other by frequent exchanges of reproductive males. Analyses of correlation between geographic and genetic distances between troops revealed that the gene constitutions of two troops apart more than 100 km on an island could be regarded as practically independent of each other. These results suggest that the population structure of the Japanese macaque species has a tendency to split into a number of local subpopulations in which the effect of random genetic drift is prevailing.  相似文献   
42.
Bacteriological and serological characteristics of three Bacillus thuringiensis isolates obtained in Japan were investigated. They formed typical rhomboidal parasporal inclusions but flagellar (H) antigens of these isolates were different from those of the known 17 H serotypes of B. thuringiensis. The three isolates were divided into two new serotypes (serotypes 18 and 19). The serotype 18 isolate (3–71) produced thermostable exotoxin and the inclusions of this isolate were toxic to larvae of the silkworm, Bombyx mori, but nontoxic to larvae of the mosquito, Aedes aegypti. The other isolate (119-72) belonging to serotype 18 produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. However, other bacteriological properties of the isolate 119-72 were similar to those of the isolate 3–71. The serotype 19 isolate (117-72) produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. Acid production from saccharose and the production of brownish purple pigment were observed in the two serotype 18 isolates, while neither of them was observed in the serotype 19 isolate. In other 29 biochemical properties tested, there was no difference among the three isolates. Based on these characteristics, the following two subspecies names are proposed: Bacillus thuringiensis subsp. kumamotoensis (serotype 18) for the type strain 3–71 and Bacillus thuringiensis subsp. tochigiensis (serotype 19) for the type strain 117-72.  相似文献   
43.
The changes in the energy substrate utilized by the remnant liver were studied in relation to the changes in the cellular energy status of 25 and 70% hepatectomized rabbits. In 25% hepatectomized rabbits, the energy charge ((ATP+0.5ADP)(ATP+ADP+AMP)) level of the remnant liver remained unchanged, the energy substrate of which was predominantly glucose, rather than fatty acid. In contrast, in 70% hepatectomized rabbits, the energy production by the mitochondria was mainly dependent upon fatty acid oxidation at the early period after hepatectomy when the energy charge level decreased remarkably, and then upon glucose oxidation, concomitant with the restoration of the energy charge. It is suggested that the changes in the energy substrate utilized are closely related to those in the energy charge level and the mitochondrial phosphorylative activity of the remnant liver following hepatectomy.  相似文献   
44.
Many nodal cells are interposed between two internodal cellsof Chara braunii. When an action potential conducted in an internodereached the node, no electrical activation in the nodal cellscould be found, although an area of the membrane bordering thenodal cells in this internode was partially activated (end-membraneaction potential). When the action potential approached thenode along the stimulated internode, an electrotonic potentialchange (depolarization) was produced in the other internode.This depolarization was greatly depressed by the end-membraneaction potential of the stimulated internode, so that hardlyany transmission took place. The ratio of the potential changein the surface membrane of the adjoining ("postsynaptic") internode(cell b) to that of the stimulated one (cell a), the couplingratio, eb/ea, can be estimated from a simple equivalent circuitof the nodal region composed of two surface-membrane resistances(Ra, Rb) and intercellular resistance (Rn). If Rn remains thesame, a higher ratio should be produced with a larger Rb, butthe ratio does not depend on any change in Ra, which could beproved experimentally. Transmission of the action potentialbeyond the node was frequent when the coupling ratio was increasedand when the threshold that elicits the action potential waslowered by immersing the node in a K or Na salt solution. 1 Present address: Department of Physiology, Tohoku UniversitySchool of Dentistry, Sendai 980, Japan. (Received December 1, 1980; Accepted January 23, 1981)  相似文献   
45.
The natural hybridization betweenPapio anubis andP. hamadryas in central Ethiopia was studied from a population genetical perspective. Studies were made using electrophoretical blood protein variations as markers in order to clarify the genetic relationship between them. A total of 563 samples from ten populations which were collected in the field studies with a socioecologist in 1976 and 1979 were examined for 34 blood protein loci. Ten of the 34 loci showed polymorphism. The Tf, PA-2 and Es were found to be effective for discriminating between the anubis and hamadryas. Genetic variability, hybridization rate, genetic distance, migration rates and correlations between genetical and morphological and between genetical and behavioral indices were computed and analyzed. The results of the present genetic survey revealed that most of the populations from which the author collected blood samples were more or less hybridized. The Nei's (1975) genetic distance between the two species was estimated to be 0.0679 at most. As this value is too small to consider these species as real biological species, it is supposed that the natural hybrid zone is fairly wide and still expanding now. This work was supported in part by Grants in aid for scientific research (Overseas scientific research, 1975) and of the Overseas Special Research Programme of the Primate Research Institute, Kyoto University in 1978 by Ministry of Education, Science and Culture.  相似文献   
46.
Fusarium solani M-13-1 was shake-cultured in a medium containing guaiacylglycerol-β-coniferyl ether (I), a model compound representing the arylglycerol-β-aryl ether linkage in lignin, as sole carbon source. From the culture filtrate guaiacylglycerol-β-coniferyl aldehyde ether (II) and guaiacylglycerol-β-ferulic acid ether (III) were isolated as metabolic products. Incubation with (III) resulted in formation of guaiacylglycerol-β-vanillin ether (IV), which was further metabolized to guaiacyglycerol-β-vanillic acid ether (V). The results indicate that the cinnamyl alcohol group of (I) is initially oxidized to an aldehyde group, which is further oxidized to a carboxyl group, yielding (II) and (III). Compound (III) is converted to (IV) by the release of a C2 fragment, and the aldehyde group of (IV) is further oxidized to a carboxyl group, giving (V). In the pathway from (I) to (V), neither oxidation of the benzylic secondary alcohol to ketone nor cleavage of the arylglycerol-β-aryl ether linkage was observed. The fungus was found to attack both erythro and threo form without distinction.  相似文献   
47.
Cytochromes P-450 and b5 were observed in the microsomal fraction of interstitial tissue of rat testes. Microsomal cytochrome b5 was reduced by the NADH coupled with the activities of Δ5-3β-hydroxysteroid dehydrogenase with Δ54 isomerase through conversion of pregnenolone to progesterone. Activities of NADPH-supported 17α-hydroxylase and C-17-C-20 lyase which converted progesterone to androstenedione were stimulated by either the presence of NADH or the oxidative reaction by the dehydrogenase upon Δ5-3β-hydroxysteroids. Androstenedione production enhanced by the reaction of the dehydrogenase was decreased by addition of the antibody against NADH-cytochrome b5 reductase which was purified from rat hepatic microsomes, suggesting the active participation of cytochrome b5 in the androgen synthesis.  相似文献   
48.
Genetic variation at the locus controlling A1 band of erythrocyte esterase was found in the Japanese macaque,Macaca fuscata. Existence of four alleles,Es-A 1 1 ,Es-A 1 2 ,Es-A 1 3 , andEs-A 1 4 , controlling the mobility of the band and codominance relation between them were postulated. A majority of the troops examined were monomorphic inEs-A 1 1-1 phenotype, and the variant phenotypes were observed to occur only in Yugawara-Ihama, Arashiyama, and Koshima areas.  相似文献   
49.
In order to clarify the genetic relationships between troops of Japanese macaques, the authors have been looking for the genetic variation of blood proteins by electrophoretical technique. In this work the genetic variants of erythrocyte carbonic anhydrase isozymes of 1273 blood samples from 34 troops of this species were examined. The genetic polymorphisms were observed in several troops. The variable troops of CA I were Fukushima, Takasakiyama, Kohchi, Shimane, Shodoshima I, K, and T, Kashima, Kawara, Takasakiyama A, B, and C, and Tomogashima. The variant allele found in these troops is onlyd 2 allele, which was probably identical with that reported byTashian et al. (1971). The frequencies ofd 2 allele in the Shodoshima and Kashima troops were very high, and this phenomenon was interpreted as being a result of the founder effect and the random fluctuation of gene frequencies in these troops.  相似文献   
50.
A water-soluble glucuronan “protuberic acid”, [α]d22 −83.6° and purified from Kobayashia Nipponica, and its physicochemical properties were investigated.The purified protuberic acid was homogeneous as shown by zone electrophoresis, gel filtration over Sepharose 4B, and ultracentrifugation. The sedimentation coefficient was 1.8 S and its intrinsic viscosity was 1.1 dl/g. By gel filtration the molecular weight was estimated to be about 170 000. The results of periodate oxidation, methylation analysis, and partial acid hydrolysis indicated that this acidic polysaccharide has a linear structure of mainly 1,4-linkages and containing an acid-labile linkage. Reduced protuberic acid, [α]d22 −44°, is also described.  相似文献   
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