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91.
Suppressor activity of bovine Fc gamma positive cells during a persistent infection with Mycobacterium avium 总被引:1,自引:0,他引:1
The cell mediated immune response (CMI) was measured in calves after experimental infection with Mycobacterium avium. Using the tuberculin skin test a CMI response could be measured from four to 14 weeks after infection, and with a lymphocyte stimulation (LS) test from six to 40 weeks. One year after infection no CMI response was detected by either of the tests, in spite of the fact that in such calves M avium bacteria could be found in the intestinal lymph nodes at autopsy. After removal of mononuclear cells bearing receptors for the Fc part of IgG, the peripheral blood lymphocytes obtained from a calf infected one year earlier responded to M avium pure protein derivative in the LS test in contrast to lymphocytes obtained from uninfected calves. 相似文献
92.
Breeding ewes in drylot were fed pelleted complete diets with 3% cottonseed meal (CSM) or 7% dried, gamma-irradiated sewage solids (DGSS) for 4 yr. Cytochrome P-450 (P-450) content and enzyme activities for xenobiotics biotransformations were assayed in livers after 2 yr and in livers, kidneys and ileal tissue after 4 yr. Dietary DGSS caused no increase in P-450 and few changes in activities of oxidative, hydrolative and conjugative biotransformational enzymes. Consumption of DGSS for 4 yr caused slight enlargement of spleens (1.1-fold, P less than .10) and ovaries (1.3-fold, P less than .10), but no change in size of livers, kidneys, hearts, adrenals and thyroids (P greater than .10), nor liver vitamin A levels (P greater than .10). Of 22 refractory lipophilic residues assayed in abdominal adipose tissue, few were detected and of those detected DGSS caused none to exceed normal levels. Dietary DGSS increased (P less than .01) Fe in livers 1.5-fold and in spleens 5.6-fold, and increased Cu in livers 1.3-fold (P less than .01) and in kidneys 1.2-fold (P less than .05). Dietary DGSS increased Cd levels in livers (P less than .01) but not in kidneys or spleens (P greater than .10); yet all Cd levels were within ranges for livestock fed conventional feed. Dietary DGSS caused no increase (P greater than .10) in levels of Ag, Ca, Cr, Hg, K, Mg, Mn, Na, Ni, P, Pb or Zn in livers, kidneys or spleens. There were no histopathological lesions of toxicosis except mild hemosiderosis of spleens. Consumption of a diet with 7% DGSS throughout 4 yr caused no hazardous accumulation of toxic elements and little, if any, evidence of toxicosis. 相似文献
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J Kirpensteijn R B Fingland C P Godshalk 《Journal of the American Veterinary Medical Association》1992,200(1):95-96
A 14-month-old Arabian colt was admitted for treatment of an articular fracture of the supraglenoid tubercle of the right forelimb. Successful repair was achieved by use of three 5.5-mm cortical screws placed in lag fashion across the fracture line. In other reports of supraglenoid tubercle fractures in horses, investigators have preferred conservative management or surgical removal of the fragment, because of limited success with internal fixation. Use of three 5.5-mm screws placed in lag fashion may offer an alternative method of treatment in selected cases of supraglenoid tubercle fractures. 相似文献
99.
To investigate possible circadian and ultradian periodicities for peripheral insulin and urea in lactating dairy cows, integrated 15-min blood samples were taken sequentially over 48 hr from six cows. In addition, radiotelemetry measurements of body temperature were averaged over the same 15-min periods. Cows were housed in an environmental chamber at 19 degrees C with lights on 0700 to 2300 hr; fed daily at 0900 hr; and milked at 0800 and 2000 hr. For five of the six cows, body temperature showed a circadian rhythm peaking at 2323 hr with an amplitude of 0.34 degree C. For the sixth cow, body temperature was 180 degrees out-of-phase, peaking at 1230 hr with an amplitude of 0.12 degree C. Circadian rhythms for insulin and urea were consistent for all six cows peaking at 1743 hr with an amplitude of 0.74 ng/ml for insulin and at 1034 hr with an amplitude of 3.83 mM for urea. Body temperature and insulin also displayed episodic increases that often exceeded the amplitudes of circadian rhythms. For body temperature, a broad increase in spectral power was seen for periods between 100 and 175 min; time intervals between peaks averaged around 100 min. For insulin, power spectra for individual cows universally indicated rhythms with periods of approximately 45 and 80 min; time intervals between peaks averaged approximately 65 min. For urea, almost all spectral energy was confined to the 24-hr rhythm, although there was evidence of a low-amplitude, 60-min rhythm. In conclusion, when animals are acclimated to a rigidly controlled environment and frequent blood sampling is accomplished with minimal intervention, it is possible to detect rhythms inherent in the regulation of metabolic variables. 相似文献
100.
Isolation of group eugonic fermenter-4 bacteria from a cat with multifocal suppurative pneumonia 总被引:1,自引:0,他引:1
R Drolet K B Kenefick M R Hakomaki G E Ward 《Journal of the American Veterinary Medical Association》1986,189(3):311-312
A pure growth of Group Eugonic Fermenter-4 bacteria (gram-negative) was isolated from the lungs of an 11-year-old male domestic cat that had been ill for 2 days before death. Clinical signs included anorexia, severe dyspnea, and salivation. The lungs contained several firm, slightly raised, yellowish-gray, spherical nodules of various sizes. Purulent exudate was found in the pericardial sac and left pleural cavity. Histologic evaluation revealed multifocal suppurative pneumonia. 相似文献