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131.
We investigated the genetic structure of populations of the brackish-water crab Deiratonotus cristatus (de Man, 1895) (family Camptandriidae) on the Japanese coast, together with morphological and the ecological variations. Genetic characteristics of the local populations based on mitochondrial DNA COI sequence data have revealed genetic differentiation between many populations, with the haplotype networks forming three geographical clades: a clade occurring on the Pacific coast, one occurring predominantly in northern Hokkaido, Kyushu and the Seto Inland Sea, and a third occurring in the Ryukyu Islands. Male pleopod morphology, carapace length relative to carapace width, and carapace width of adult crabs varied inconsistently among the geographic groups corresponding to the three clades. Life history traits were similar throughout, although differences in the breeding season were apparent between populations on the Pacific coast, and in the Seto Inland Sea and the Ryukyu Islands. 相似文献
132.
133.
134.
Boric acid inhibited the acid-catalyzed depolymerization of cellulose in sulfolane, a non-aqueous medium, at high temperature. Formation of the dehydration products such as levoglucosenone, furfural, and 5-hydroxymethyl furfural were also effectively inhibited. Similar inhibition was observed for cellooligosaccharides and starch, although the glucosidic bonds in methyl glucopyranosides and methyl cellobioside were cleaved to form alpha-d-glucofuranose cyclic 1,2:3,5-bisborate. 相似文献
135.
Ken Nozawa Takayoshi Shotake Yoshi Kawamoto Yuichi Tanabe 《Primates; journal of primatology》1982,23(2):252-271
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
136.
137.
Anatomy of the frontal branch of the facial nerve: the significance of the temporal fat pad 总被引:11,自引:0,他引:11
The anatomy of the temporal region, with reference to the frontal branch of the facial nerve, was examined in 12 fresh cadaver dissections. In all dissections, the frontal branch traveled in a constant plane along the undersurface of the temporoparietal fascia and was quite superficial as it crossed the zygomatic arch. The deep temporal fascia and superficial temporal fat pad are anatomically important structures which adjoin the periosteum of the zygomatic arch and lie deep to the frontal nerve. Based on these relationships, a safe method of dissection within the temporal region is formulated. 相似文献
138.
A RelC deletion mutant, KO-100, of Streptomyces coelicolor A3(2) has been isolated from a collection of spontaneous thiostrepton-resistant mutants. KO-100 grows as vigorously as the
parent strain and possesses a 6-bp deletion within the rplK, previously termed relC. When the wild-type rplK gene was propagated on a low-copy-number vector in mutant KO-100, the ability to produce ppGpp, actinorhodin and undecylprodigiosin,
which had been lost in the RelC mutant, was completely restored. Allele replacement by gene homogenotization demonstrated
that the RelC mutation is responsible for the resistance to thiostrepton and the inactivation of ppGpp, actinorhodin and undecylprodigiosin
production. Western blotting showed that ribosomes from the RelC mutant KO-100 contain only one-eighth the amount of L11 protein
found in ribosomes of the parent strain. The impairment of antibiotic production in KO-100 could be rescued by the introduction
of mutations that confer resistance to streptomycin (str), which result in alteration of Lys-88 in ribosomal protein S12 to Glu or Arg. No accompanying restoration of ppGpp synthesis
was detected in these RelC str double mutants.
Received: 12 May 1997 / Accepted: 22 July 1997 相似文献
139.
Temporomandibular ankylosis frequently involves massive bony proliferation which can approach the carotid artery at the base of the skull. During the resection of the bony ankylosis, the artery can be injured. The first such case is reported which led to a thrombosis and hemispheric stroke. 相似文献
140.