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Since treatment with Freund's complete adjuvant in chickens with congenital avian leukosisvirus infection results in severe hypergammaglobulinaemia, it was of interest to determine how various means of chemical bursectomy affected such animals. Testosterone injected during the embryonic period or cyclophosphamide administered neonatally were, alone, relatively ineffectual in suppressing the response to influenza virus or production of natural rabbit haemagglutinins, nor did these treatments reliably depress IgG or IgM levels. However, the combination of both testosterone and cyclophosphamide completely suppressed antibody responses to the antigens and resulted in animals with serum immunoglobulin levels 10-(4)-10-(5) that of untreated hypergammaglobulinaemic controls. 相似文献
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LF Gibson 《Canadian Metallurgical Quarterly》1975,75(3):413-424
A study of the incidence of diphtheria in the State of Victoria, Australia, was carried out. Numerical analysis of the characteristics of 264 strains of Corynebacterium diphtheriae isolated between 1962 and 1971 placed them into 18 varieties plus six strains which were unique in their combination of reactions to the characteristics examined. During the 10-year period, some varieties appeared intermittently and were recognized by certain defining characteristics but exhibited a gradual change in their antigenic structure. In contrast, when the outbreaks were examined over shorter periods of time, a number of varieties and single strains were found which differed greatly from each other yet possessed the same major serotype antigen. These findings are discussed in terms of a 'one-parent' concept in which the varieties and single strains represent phases of a common ancestor. By inspection and analysis of the characteristics of the strains, certain associations were apparent. For instance, a correlation was found between the antigenic structure of the organism and the colonial appearance on tellurite blood agar. Similarly, correlation was observed between bacteriophage type, diphthericin type and biochemical activity in that a strain which was highly active in one of the properties was also very active in the other two. 相似文献
155.
RR Brodie LF Chasseaud FF Elson ER Franklin T Taylor 《Canadian Metallurgical Quarterly》1976,26(5):896-901
The excretion and plasma concentrations of radioactivity and chromatographic patterns of radioactive components in plasma and excreta have been compared in rats, dogs and man after oral doses of the hypolipidemic agent isopropyl-[4'-(p-chlorobenzoyl)-2-phenoxy-2-methyl]-propionate (LF 178; procetofene; Lipanthyl?). 2. In rats, 48.1% of a single dose of 25 mg/kg was excreted in the urine, and 48.6% in the faeces. In dogs, 23.1% of a single dose at the same level was excreted in the urine, and 71.8% in the faeces, but 88.1% of a dose of 300 mg to man was excreted in the urine, and only 5.1% in the faeces. Peak levels of radioactivity in the plasma of all three species studied were similar (20--30 mug/ml) after doses at these levels and concentrations declined thereafter with half-lives of 7--24 h in rats and dogs, and 7 h in man. The half-life of radioactivity concentrations in rat plasma was not altered by repeated daily doses for 7 days. 3. Whole-body autoradiography of rats showed that radioactivity was largely associated with the liver, kidneys and gut, which are the organs of biotransformation and excretion, although relatively high levels were present in lungs and blood, and small amounts of radioactivity had a widespread distribution into some peripheral tissues during 2--7 h after dosing. 4. The available chromatographic evidence indicated that the most important biotransformation pathway appeared to be ester hydrolysis to LF 178 acid and formation of water soluble conjugates of this acid. This pathway appeared similar to that of the related drug clofibrate (ethyl p-chlorophenoxyisobutyrate). 相似文献
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NN Bogdanov LP Iakupova NL Gorbachevskaia LF Kozhushko EA Pankratova 《Canadian Metallurgical Quarterly》1993,329(2):241-245
We have examined the type I collagen protein, RNA, and cDNA of 2 children with moderately severe (type IV) osteogenesis imperfecta (OI). They have in common a non-lethal form of OI with ambulatory potential, overmodification of type I collagen protein, and a substitution of serine for glycine in the collagen chain produced by one alpha 1(I) allele. The first child (Marini et al.: J Biol Chem 264:11893-11900, 1989) is now 7 years old, with the height of a 3-year-old. Her course includes significant remodeling of lower long bones and 4 femur fractures. She walks independently. A mishmatch was detected in her alpha 1(I) mRNA using RNA/RNA hybrids; it was demonstrated to be due to a G-->A point mutation in one allele of alpha 1(I), resulting in the substitution of serine for glycine 832. The second child is now 6 1/2 years old, with the height of 1 1/2-year-old. Her history includes significant bowing of femurs and tibias, 6 femur fractures, S-curve scoliosis, compression of all lumbar vertebrae, and limited short-distance walking with braces. Her alpha 1(I) mRNA has also been studied by RNA hybrid analysis; there is a single G-->A change in one alpha 1(I) allele causing the substitution of serine for gly 352. Both children have moderately severe OI. However, the serine substitution at gly 352 is associated with a more severe phenotype then is the serine substitution at gly 832. Compared to substitutions described in other cases of OI, the serine 352 is located in the middle of a cluster of cysteine substitutions associated with non-lethal OI.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献