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122.
Rana cancrivora Gravenhorst inhabits both fresh water and brackish water swamps and ditches in Singapore. Food items in the gut of frogs from both habitats have been examined. The diet of frogs collected near brackish water was predominantly crustacean and included crabs ( Sesarma spp.), while the diet of those collected near fresh water comprised mainly insects. Gut contents of frogs included all the small animal species found in the respective environments, the choice of prey appearing to be limited only by size. 相似文献
123.
J.R.M. INAL. V. KARUNAKARAN AND H.D. BURGES. 1992. Four temperate phages, ØHD67, ØHD130, ØHD228 and ØHD248, which were isolated from Bacillus thuringiensis H-serotype 7 strains, were tested for their ability to mediate transduction within H-serotype 7 and also between H-serotype 7 and 3a3b. The optimum conditions to facilitate transduction were determined. The four phages successfully mediated transduction within serotype 7 of all five auxotrophic markers tested and thus seem to have the ability to mediate generalized transduction. The phages also mediated transduction between H-serotype 7 and H-serotype 3a3b of 10 of 11 auxotrophic markers tested. 相似文献
124.
This study describes the isolation of temperate B. anthracis phages, from 4 out of 20 B. anthracis strains screened, by use of the inducing agents mitomycin C and UV light. Phage φ20 isolated from B. anthracis Sterne 34F2 (pXO1+ pXO2−) was shown to have double-stranded DNA of size 48756 bp and a restriction site map showing nine sites for enzymes BamHI, BglII, and SstI is included. The φ20 genome was found to exist as a plasmidial prophage and the phage itself to have a polyhedral head of
diameter 65 nm and tail 217 nm long and 15 nm wide. 相似文献
125.
Studies with gamma rays, fast neutrons, and EMS treatments in rice showed higher frequency of M1 chlorophyll chimeras in the EMS treatments, a correlation between the frequencies of M1 chlorophyll chimeras and M2 chlorophyll mutants, and a higher M2 mutation frequency in the progeny of chimerical M1 plants compared to those of normal-looking plants. 相似文献
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127.
This study describes the isolation of a phage, using mitomycin C and u.v. light, from each of four strains (HD67, HD130, HD228 and HD248) of Bacillus thuringiensis H-serotype 7 (var. aizawai). It also describes the isolation of two indicator strains (12.13 and HD 102) for these phages (φHD67, φHD130, φHD228 and φHD248) and the ideal conditions, using these indicator strains, for maximum phage production. 相似文献