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941.
942.
943.
The normal course of development of electrophoretic serum protein patterns has been examined in two hybrid strains of chicks during the 7 weeks after hatching and was found to proceed distinctively. Hybrid A (susceptible to aflatoxin) had an almost constant mean serum protein concentration over this period. On the other hand, after a high mean concentration (4–09 g./100 ml.) in day‐old chicks of hybrid B (less susceptible to aflatoxin) there was a fall to 2.69 g./100 ml. at 7 days, followed by a gradual increase to 3.28 g./100 ml., approximately the level found throughout the experiment in hybrid A.

Proportions of albumin and total globulins varied in an almost identical manner in each group. Day‐old chicks of hybrid A had significantly lower β‐ and γ‐globulin concentrations and at 7 days, when there was a maximum difference in mean total protein concentrations, the serum albumin content was significantly higher in this hybrid.  相似文献   

944.
945.
Atopy.     
Atopy should be considered an immunological disorder that may result in several clinical conditions including respiratory disease, allergic dermatitis, food allergy dermatitis, and perhaps flea allergy dermatitis. The clinical course of the disease tends to fluctuate from season to season, which makes objective evaluation of injection therapy difficult. The disease is subject to both familial and environmental influences, and dogs maintain the atopic state throughout their life. The disease cannot be cured; however, a combination of symptomatic and specific injection therapy usually provides adequate control of the clinical signs. Owners of atopic dogs should appreciate that their pet has inherently itching skin, a cure for which is unlikely to be found.  相似文献   
946.
Virus was isolated from semen and fecal samples from a bull with orchitis, testicular degeneration, aspermatogenesis, and loss of libido. Both isolates were classified as picornavirus, bovine enterovirus serotype I, on the basis of physical, chemical, and serologic characteristics. Veterinary practitioners that may suspect viral infection as a cause of bovine infertility should submit both semen and fecal samples for virus isolation and identification.  相似文献   
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950.
The double-isotope single-injection method to estimate renal function which utilizes the radiolabeled chemicals [131I]sodium iodohippurate and [125I]sodium iothalamate was evaluated in swine. A total of 46 normal, cross-bred swine were used to determine the applicability of this method for measuring the glomerular filtration rate and effective renal plasma flow. The mean glomerular filtration rate in pigs was determined to be 5.33 +/- 0.82 ml/kg of body weight/minute for [125I]sodium iothalamate with a biological half-life (T 1/2) of 39.18 +/- 7.44 minutes. The mean effective renal plasma flow was determined to be 19.25 +/- 3.12 ml/kg of body weight/minute for [313I]sodium iodohippurate, with a T 1/2 of 18.45 +/- 1.74 minutes. These values are more closely related to the glomerular filtration and effective renal plasma flow values reported for dogs and cats than they are to values reported for man. The method is rapid and reliable; results are available 6 to 8 hours after the experiment. This method is advantageous when information about renal function variables is a prerequisite to pharmacokinetic or toxicologic studies.  相似文献   
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