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971.
972.
Induction of parturition in swine with prostaglandin F2alpha   总被引:3,自引:0,他引:3  
  相似文献   
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Experimental colibacillary (Escherichia coli) enterotoxemia as described in this report mimics natural edema disease both clinically and in gross pathology. The histopathology is characterized by accumulations of non-inflammatory edema and by arteriopathy. The smaller arterial and arteriolar changes recorded here are similar to those described in natural edema disease. The vascular changes described in recovered cases of experimental colibacillary enterotoxemia concur with those reported in so-called subacute and chronic edema disease. The arteriolar changes that occur in colibacillary enterotoxemia of swine are comparable to those associated with hypertension.

Thin sections of cerebral cortex from four pigs with acute experimental edema disease were examined by electron microscopy in an attempt to demonstrate brain edema. Sections from one pig taken during the convulsive phase of disease revealed dilatation of perivascular glial processes. However, examination of sections taken from three other pigs during an earlier phase of the neurological disturbance revealed no significant lesions. We were unable to ascertain the role of brain edema in the pathogenesis of the nervous system disturbance in these experiments.

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Daily fluctuations of cortisol concentration in the blood or saliva have been repeatedly reported. However, several contradictions in the existing literature appear on this subject. The present study was performed to definitively establish options for testing adrenocortical function. To the best of our knowledge, this is the first study to evaluate parallel circadian rhythms in salivary and serum cortisol concentrations during a 24-h period. Twenty horses were examined under the same conditions. Blood and saliva samples were taken every 2 h for 24 h to determine the daily changes in cortisol concentrations of saliva and serum at rest and to determine the relationship between salivary and serum cortisol levels. Cosinor analysis of group mean data confirmed a significant circadian component for both serum and salivary cortisol concentrations (P < 0.001 in both cases). The serum cortisol circadian rhythm had an acrophase at 10:50 AM (95% CI, 10:00 AM–11:40 AM), a MESOR of 22.67 ng/mL, and an amplitude of 11.93 ng/mL. The salivary cortisol circadian rhythm had an acrophase at 10:00 AM (95% CI, 9:00 AM–11:00 AM), a MESOR of 0.52 ng/mL, and an amplitude of 0.12 ng/mL. We found a significant but weak association between salivary and serum cortisol concentrations; the Pearson correlation coefficient was 0.32 (P < 0.001). The use of salivary cortisol level as an indicator of hypothalamic-pituitary-adrenal axis activity may be warranted. However, the salivary cortisol levels are more likely to be correlated with free plasma cortisol than with the total plasma cortisol concentration.  相似文献   
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A 2-year-old Standardbred gelding was referred for a mass on the palmaromedial right front pastern which was accompanied by progressively worsening lameness. The mass was firm to palpation and covered by normal skin. Ultrasonographically, a smooth encapsulated mass was present, medial to the flexor tendons and palmar to the neurovascular bundle. Because of a poor prognosis for future athletic performance without surgical or chemotherapeutic intervention and economic constraints preventing further diagnostics and treatment, the horse was euthanised. Post-mortem magnetic resonance imaging, histopathology and immunohistochemistry revealed the mass to be a perivascular wall tumour, the first record of such a neoplasia in the horse.  相似文献   
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