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941.
1. The electrophoretic patterns of water‐soluble proteins of avian muscle showed differences due both to species and to muscle type.
2. Each muscle pattern within a species showed a unique protein band which distinguished that species from other species. 相似文献
942.
943.
An outbreak of S. typhimurium gastroenteritis and septicemia is described in young cats admitted to a veterinary hospital for routine medical and surgical reasons. A morbidity of 32% and a mortality of 61% was observed in the outbreak. Affected cats exhibited oral shedding of the organism and contaminated feed and water dishes may have been the vehicle of spread of infection. Possible detrimental effects of incorrect choice of antibiotic therapy are discussed. Attempts to reproduce the disease in a group of laboratory cats were unsuccessful. Antibody production was poorly correlated with infection in these cats. 相似文献
944.
945.
The ability of nine strains of avian infectious bronchitis virus (IBV) to induce chicken interferon has been investigated using Semliki Forest virus for the tests. The Beaudette, H120 and Connecticut 46 strains induced interferon in the allantoic fluids of embryonated hens' eggs, the highest titre (1 : 30) being associated with Beaudette; but these as well as the Massachusetts M-41 and H52 strains failed to yield interferon in primary monolayer cultures of chick kidney cells as did all nine strains in organ cultures of chick embryo trachea. None of six strains of IBV investigated was susceptible to the inhibitory effects of chicken interferon. 相似文献
946.
A complement fixing antigen in the livers of birds infected with an avian leukovirus (erythroblastosis virus). 总被引:1,自引:1,他引:0 下载免费PDF全文
C Q Darcel 《Canadian journal of veterinary research》1978,42(2):235-238
Extracts of erythroblastosis affected livers from which much of the structural protein had been removed were prepared by acid denaturation. These extracts contained complement fixing "soluble" antigen in a form which was not associated with viral or subviral particles. Ultracentrifugation can be of assistance in separating complement fixation activity from contaminating material in these extracts. 相似文献
947.
Sediment samples were collected from a subarctic salt marsh on James Bay, Ontario in May 1976. Of 15 organochlorine compounds analyzed, trace amounts mainly of p,p-DDE and polychlorinated biphenyls (PCBs) were detected, but could not be quantitated. 相似文献
948.
The absorption, distribution, and metabolic fate of [14C]ethephon in flue-cured tobacco (Nicotiana tabacum L.) was studied using autoradiography, thin-layer chromatography, high-voltage paper electrophoresis, and liquid scintillation spectrometry. Labeled ethephon penetrated mature leaf tissue easily and was translocated primarily in an acropetal direction. No 14C activity was detected in any other plant part except the treated leaf. The first day after treatment, most of the translocated 14C was detected in the midrib, and after 2 days radioactivity was noticed in veinal areas distal to the point of application. Four days later, however, 14C was detected in slight amounts only in the midrib, indicating that [14C]ethephon was rapidly degraded by the leaf tissue. Depending on leaf position on the stalk, as much as 92% of the radioactivity had disappeared from the leaf tissue during the first day after treatment, and as little as 5% of the applied radioactivity was recovered 4 days later. Methanol-extracted plant residues contained insignificant amounts of 14C. All of the 14C in methanol extracts was present in the form of a labeled compound with an Rf value corresponding to that of ethephon, indicating the absence of any detectable metabolites of the parent compound. Smoke analysis of cigarettes showed that more [14C]ethylene than 14CO2 was recovered in the main stream, whereas the trend was reversed in the case of side stream smoke. 相似文献
949.
C. J. Savory 《British poultry science》1976,17(5):557-560
1. Female broiler chicks reared in a 12‐h photoperiod which included a simulated “dawn” and “dusk” grew slightly faster than those reared in a 12‐h photoperiod of uniform light and others kept in continuous light.
2. This was apparently because the chicks subjected to dawn and dusk ate more food than those subjected to 12‐h uniform light and converted food more efficiently than those in continuous light. 相似文献
950.
Cytogenetic and histological studies were carried out on an intersex horse which was diagnosed clinically as a cryptorchid. Surgery confirmed the horse to be a bilateral abdominal cryptorchid and histological examination revealed ovarian tissue associated with the left epididymis. Chromosome analysis of cultured cells from testicular tissue, ovarian tissue and skin revealed 64-XX and 64-XY make-up, the left gonad containing a greater preponderance of XX cells over XY cells. The external characteristics and behaviour of the horse were indistinguishable from that of a "routine" cryptorchid. Other cases of equine intersexes are reviewed and theories for the discrepancies between genetic, gonadal and phenotypic sex are discussed. 相似文献