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991.
The percentage of lymphoid cells from the bursa of Fabricius, thymus, spleen, peripheral blood, and cecal tonsils reactin with chicken antisera to turkey bursa and thymus were evaluated, using 1-day-old to 5-week-old turkeys. For this, rabbit anti-chicken globulin fluorescein isothiocyanate conjugate was used. The percentage of lymphoid cells showing immunoglobulin surface determinants from these organs also was examined, using a direct immunofluorescence test with a rabbit anti-turkey globulin fluorescein isothiocyanate conjugate. This study suggests that the bursa-specific antigen and immunoglobulin surface determinants could be used as markers for bursa-derived cells in the turkey. It also was found that thymus-specific antigen could be used as a marker for thymus-derived cells.  相似文献   
992.
Partially purified alkaline phosphatase (ALP) from canine intestine, liver, and bone were injected into rabbits to elicit anti-canine intestinal, hepatic, and osseous ALP antibodies, respectively. The antibody formed a soluble enzyme-antienzyme complex when directly interacted with the ALP antigen. In order to form an insoluble complex, it was then necessary to interact the initial soluble complex with the goat anti-rabbit gamma-globulin antibody in the 2nd step. Antiintestinal ALP antibody was highly specific and did not cross react with canine hepatic, osseous, splenic, and renal ALP. Antiliver and antibone ALP antibodies, on the other hand, did cross react with hepatic, osseous, splenic, and renal ALP, but not with the intestinal ALP.  相似文献   
993.
The Australian strain of infectious bursal disease virus (IBDV), 002/73, affected the response of chickens to Newcastle disease virus (NDV). The titre of serum antibodies to NDV in chickens infected with IBDV was significantly lower than that of birds infected with NDV alone. It also appeared that IBDV affected NDV excretion from chickens as NDV was more frequently isolated from chickens infected with IBDV, IBDV infection did not alter the pathogenicity of NDV in chickens. This Australian strain of IBDV therefore appeared to be immunodepressive in one-day-old chickens.  相似文献   
994.
The genital tracts of 968 slaughtered bulls (46% of which were young post-puberal animals) were examined for defects of a congenital or developmental nature. The overall occurrence of such lesions was 7%. These comprised persistent penile frenulum (0.5%), hypospadias (0.3%), detached urethral process (0.4%), testicular hypoplasia (0.2%), cryptorchidism (0.6%), mesonephric duct abnormalities (1.1%) and bulbourethral cysts, fusion and aplasia (3.6%). Segmental aplasia of the mesonephric duct, not previously recorded in the study area, was found in 4 Shorthorn bulls (0.4%); 2 affected animals were from one herd. In 3 cases of hypospadias (2 from one herd), the urethra communicated with the ventral surface of the penis at the junction of the body and glans through a slit-like orifice. The occurrence of defects observed was generally comparable to that found in bull populations elsewhere but elevated occurrence of several defects in particular herds emphasized the need for further study.  相似文献   
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997.
Infectious avian encephalomyelitis virus (IAEV) maternal antibody was detected in the serum of chickens for up to 21 days following hatching. This antibody protected chickens against clinical IAE after intracerebral inoculation with van Roekel strain or oral administration of the NSW-1 strain of IAEV. Maternal antibody to IAEV also protected testosterone bursectomised chickens against the development of clinical disease. IAEV maternal antibody also influeced the pattern of virus excretion in faeces and serological responsiveness. This influence on antibody responses persisted beyond the time that IAEV maternal antibody could be detected. The importance of IAEV maternal antibody on the strategy of vaccination against IAE is discussed.  相似文献   
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Aprotinin, a proteinase inhibitor, was evaluated as a pharmacologic aid in dogs subjected to lethal hemorrhagic shock. Survival time, hemodynamic changes, and plasma enzyme analysis were measured as criteria for drug effects. Mixed-breed dogs (n = 14) were divided into 2 groups of 7 each: nontreated dogs in shock (group 1) and aprotinin-treated dogs in shock (group 2). One of 7 dogs in group 1 and 2 of 7 dogs in group 2 survived. Survival time, for the remaining dogs in group 1 (190 min, n = 6) and group 2 (188 min, n = 5) were not significantly different. There was no significant difference in mean arterial pressure, mean pulmonary arterial pressure, cardiac output, or left ventricle systolic pressure associated with aprotinin treatment at any time after hemorrhagic shock. There was no significant difference in plasma lactic acid, aspartate aminotransferase, alanine aminotransferase, creatine phosphokinase, alpha-amylase, and beta-glucuronidase associated with treatment at any time; however, there were significant (P less than 0.05) increases with time. The gastrointestinal tract was the site of most obvious lesions found at necropsy. Lesions varied considerably in extent and severity without apparent correlation to the treatment regimen. These experiments did not show beneficial effects of aprotinin in dogs subjected to hemorrhagic shock, but neither did they completely rule out some valuable actions that may have been obscured by the type of model used.  相似文献   
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