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991.
A new short-term natural gas consumption model is developed, tested against American Gas Association sales data, and applied to the question of the effectiveness of conservation efforts. The results indicate that unit residential gas-heating sales per heating degree-day have remained constant in four major gas-consuming regions during the period 1974 to 1976 and that heating sales have not been affected by the recent sharp changes in price. 相似文献
992.
993.
Carter LJ 《Science (New York, N.Y.)》1978,200(4349):1469-1470
994.
995.
996.
R. J. Dixon W. J. Hartley D. R. Hutchins E. E. Lepherd Caroline Feilen † R. F. Jones † Daria N. Love † Margaret Sabine † Anne L. Wells † 《Australian veterinary journal》1978,54(3):103-105
An outbreak of perinatal foal mortality associated with a herpesvirus is described. Twenty two foals either were still-born, or died soon after birth, or were weak and soon developed severe respiratory signs, or were normal at birth and developed respiratory symptoms 18 to 24 hours later. Elevated temperatures, heart and respiratory rates were constant features. The animals were severely leucopaenic, and showed an absolute neutropaenia. At autopsy the lungs were enlarged, and showed varying degrees of aeration and moderate to severe oedema and congestion. Histopathology showed an acute focal necrotising bronchiolitis with the presence of intranuclear eosinophilic inclusion bodies. Herpesvirus was recovered from 9 foals in cell culture and identified by electron microscopy. 相似文献
997.
H. A. Westbury 《Australian veterinary journal》1978,54(7):349-351
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
998.
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
999.
1000.
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