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81.
A rapid urea-phenylalanine medium was effective for the identification of Proteus and, with one exception, Providencia. Most Klebsiella and a few Enterobacter were urease-positive with this method. 相似文献
82.
Chromosomes and sex determination of 9 species of Haemaphysalis assigned to 4 subgenera are described. H. (tAlloceraea) kitaokai possesses an XX∶XO sex chromosome system with 18 autosomes plus XX in females; 18 plus X in males. H. (Kaiseriana) hystricis has 18 +XX and 18 + XY in females and males, respectively, in most specimens, but a supernumerary chromosome is present in some individuals. A supernumerary chromosome was also observed in 1 male H. (Aborphysalis) formosensis. These two species are the second and third species of ticks reported to have supernumerary chromosomes. H. formosensis, H. (Kaiseriana) bispinosa, H. (Haemaphysalis) campanulata, H. (H.) flava, H. (H.) megaspinosa, H. (H.) japonica, and H. (H.) pentalagi possess 20 autosomes plus 2 sex chromosomes in females and 20+1 sex chromosomes in males. Phylogenetic relationships within the genus Haemaphysalis are briefly discussed. 相似文献
83.
A medium consisting of an aqueous extract of zein, lactose, and Tween 80 is used together with an overlay of 1 % Tween 80 and coverslipping to provide a combined rapid (germ tube) and standard (chlamydospore) method for diagnosis ofCandida albicans. The method is exquisitely sensitive for diagnosis ofC. albicans but lumps chlamydospore-producing strains ofC. tropicalis withC. albicans. 相似文献
84.
Histology and fine structure of spermatozoa and egg passage in the female tract of Dermacentro andersoni stiles (acari-Ixodidae) 总被引:1,自引:0,他引:1
The final phase of spermiogenesis in the hard tick Dermacentor andersoni occurs in the seminal receptacle of engorged females. This phase is characterized mainly by rupture of the outer sheath of advanced spermatids at their pointed tips, and subsequent elongation as the internal column of these cells evaginates. The sheath invaginates at the opposite end to form the narrow posterior half of the sperm cell. Rupture of the endospermatophoric wall releases the large mass of contained spermatozoa, which begin migration up one or both oviducts. During the migration to the ovarian lumen, spermatozoa exhibit a propensity for active penetration of epithelial cells lining the oviducts. This phenomenon is also observed with spermatozoa in the ovarian lumen. Penetration of epithelial cells by spermatozoa is interpreted to be a response by the latter in seeking eggs for penetration and fertilization. 相似文献
85.
86.
E. Edward Peeples Ann Geisler Carol J. Whitcraft Clarence P. Oliver 《Biochemical genetics》1969,3(6):563-569
Phenol oxidase activity of activated A1 and A2 (A3) electrophoretic components from 19 lozenge mutant and three lozenge double mutant strains was compared to that of wild type flies. Melanin production by the activated A components with tyrosine as substrate was compared to activity in the same acrylamide gels with dopa as substrate. Melanin production decreased, first in the A1 band and then in the A2 (A3) band, with increased morphological expression of the mutant genes. No melanin bands were obtained with either substrate in five of the more severely affected mutants. A possible correlation between phenol oxidase activity and quinone production necessary for normal development of eyes, female accessory sex organs, and claws is discussed.Supported by PHS grant AM-08331-05. 相似文献
87.
THE METABOLISM OF PALMITIC ACID IN THE PHOSPHOLIPIDS, NEUTRAL GLYCERIDES AND GALACTOLIPIDS OF MOUSE BRAIN 总被引:6,自引:4,他引:2
Abstract— Following intracerebral injection, [14 C]palmitic acid was rapidly incorporated into a variety of brain lipids. After 12 hr, 78 per cent of the lipid radioactivity was in phospholipids, 15 per cent was in triacylglycerols, 1 per cent each was in free fatty acids and galactolipids, and the remainder was in other neutral glycerides. Over 65 per cent of the phospholipid radioactivity was found in the choline phosphoglycerides but this proportion decreased substantially with time. At later times, increasing portions of the radioactivity were present in the monounsaturated acyl groups and the alkenyl groups but no radioactivity was detected in cholesterol or polyunsaturated acyl groups. These results indicate that most of the extensive recycling of radioactivity took place without oxidative degradation of the palmitoyl groups. The relative rates of incorporation of radioactivity were compared at 12 hr after injection. The specific radioactivities of the serine, ethanolamine, and choline phosphoglycerides had ratios of 6:3:2 based on the palmitoyl group content and 1:2:4 based on their phosphorus content. The specific radioactivities of galactolipids with O -acyl groups were higher than the specific radioactivitiesof cerebrosides or cerebroside sulphates. A new solvent mixture for thin-layer chromatography of brain galactolipids was described (chloroform-acetone-methanol-water, 60:20:20:1, by vol.). 相似文献
88.
Effect of dihydroergotamine and propranolol on dibutyryl cyclic 3',5'-AMP-induced lipolysis in isolated rat fat cells 总被引:1,自引:0,他引:1
89.
90.
A man presented with the sudden onset of pernicious anaemia at the age of 21. He had been treated for hypothyroidism since the age of 6. His father and only paternal aunt were also found to have pernicious anaemia. Gastric and thyroid antibody studies showed one or more antibodies to be present in all three subjects, as well as in the patient''s mother. 相似文献