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141.
Estradiol concentrations are evaluated in canine serum as part of an adrenal panel used to diagnose atypical Cushing’s syndrome and other endocrine abnormalities. Estradiol concentrations are often elevated in dogs without clinical signs of hyperestrogenism, and the significance of this elevation is unknown. The purpose of this study was to estimate the variation in estradiol concentrations in normal dogs. Ten neutered male and female dogs were enrolled in the study. Blood was collected from each dog at 2 h intervals, four times during a given day. This was repeated approximately 1 (week 2) and 5 weeks later (week 6). There was no attempt for a given dog to be started at the exact time or day each week. Results showed that estradiol concentrations ranged from 44.6 to 120.3 pg/mL with a mean of 70.4 pg/mL, which is greater than the upper limit of normal for our laboratory (69 pg/mL). The mean difference between the highest and lowest concentrations for each dog was 28.8 pg/mL, with a range of 12.5–53.5 pg/mL. Mean estradiol concentrations from week 6 (63.2 pg/mL) were significantly lower than those from week 1 (71.4 pg/mL; P = 0.015) and week 2 (76.5 pg/mL; P = 0.0004). These data show a wide range of variability in estradiol concentration both within and between dogs and that these measurements often exceed the normal ranges established by the laboratory. Therefore, diagnosis of hyperestrogenism or atypical Cushing’s syndrome based on increased estradiol concentrations should require compatible clinical presentation of hyperestrogenism together with elevated serum estradiol. 相似文献
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Michelle Henry Barton Chrysann Collates 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1999,13(5):457-464
The purpose of this study was to evaluate the diagnostic and prognostic significance of tumor necrosis factor-alpha (TNF) and interleukin-6 (IL-6) activities and endotoxin concentration in blood and peritoneal fluid of 155 adult horses with acute abdominal disease (colic). Samples also were obtained from 20 healthy adult horses. Blood and peritoneal fluid supernatant TNF and IL-6 activities and endotoxin concentration were significantly greater in horses with colic, compared with healthy horses. In horses with colic, the peritoneal fluid endotoxin concentration and TNF and IL-6 activities were significantly greater than those in blood. Within the colic group, peritoneal fluid IL-6 activity was the analyte that was most frequently increased. Blood and peritoneal fluid supernatant TNF and IL-6 activities were significantly greater when endotoxin was detected in the same sample. Blood and peritoneal fluid IL-6 activity was significantly greater in horses with inflammatory or strangulating lesions, compared with horses having nonstrangulating or noninflammatory lesions. Compared with all other data categories, diagnostic accuracy for nonsurvival was greatest (80%) when blood IL-6 activity exceeded 60 units/mL. The results of this study indicate that endotoxin was present in the peritoneal cavity of at least one third of horses with any acute disease of the abdomen. In horses presented for colic, blood or peritoneal fluid IL-6 activity was more useful than either TNF activity or endotoxin concentration for distinguishing lesion type. Although diagnostic accuracy for the prediction of nonsurvival was good for all of the analytes, negative values were more useful in the prediction of a favorable outcome than were abnormally increased values in the prediction of mortality. 相似文献
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Sensitive enzyme immunoassays (EIA) were developed to monitor antibody (Ab) production in the koala, in response to both soluble and particulate antigens (Ag). When compared with a eutherian mammal, the rabbit, both the dynamics and kinetics of Ab production in the koala were found to be severely retarded. In vitro, Ag specific lymphocyte proliferative responses were demonstrated for the first time in this animal by sensitising koalas in vivo with Bacillus Calmet-Guerin (BCG), with the level and timing of this cell mediated immune (CMI) response comparable with those seen in non-metatherian mammals. Levels of circulating B lymphocytes were examined in an attempt to clarify the retarded humoral responses to foreign Ags. In addition, peripheral mononuclear cells (PMC) from koalas, were examined for their reactivity to a range of monoclonal Abs and lectins in an attempt to characterise these cells further. The lectins examined, demonstrated an all or none reactivity with koala lymphocytes and were therefore considered unsuitable as markers for identifying lymphoid subsets in this animal. A monoclonal Ab directed at class II MHC Ags in the mouse, demonstrated cross reactivity with a high percentage of all koala monocytes tested. Using this Ab to probe CMI responses in vitro, it is concluded that immune interactions required for such responses in the koala parallel those seen in other mammals. 相似文献
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Buchanan BR Sommardahl CS Rohrbach BW Andrews FM 《Journal of the American Veterinary Medical Association》2005,227(7):1123-1129
OBJECTIVE: To determine the effects of a 24-hour infusion of an isotonic electrolyte replacement fluid (IERF) on weight, serum and urine electrolyte concentrations, and other clinicopathologic variables in healthy neonatal foals. ANIMALS: 4 healthy 4-day-old foals. DESIGN: Prospective study. PROCEDURE: An IERF was administered to each foal at an estimated rate of 80 mL/kg/d (36.4 mL/lb/d) for 24 hours. Body weight was measured before and after the infusion period. Urine was collected via catheter during 4-hour periods; blood samples were collected at 4-hour intervals. Variables including urine production; urine and serum osmolalities; sodium, potassium, and chloride concentrations in urine and serum; urine and serum creatinine concentrations; urine osmolality-to-serum osmolality ratio (OsmR); transtubular potassium gradient (TTKG); and percentage creatinine clearance (Cr(cl)) of electrolytes were recorded at 0, 4, 8, 12, 16, 20, and 24 hours during the infusion period. Immediately after the study period, net fluid and whole-body electrolyte changes from baseline values were calculated. RESULTS: Compared with baseline values, urine and serum sodium and chloride serum concentrations, urine and serum osmolalities, OsmR, and percentage Cr(cl) of sodium and chloride were significantly increased at various time points during the infusion; urine production did not change significantly. After 24 hours, weight, TTKG, serum creatinine concentration, and whole-body potassium had significantly decreased from baseline values. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that administration of an IERF containing a physiologic concentration of sodium may not be appropriate for use in neonatal foals that require maintenance fluid therapy. 相似文献
150.
OBJECTIVE: To evaluate the effect of vaccination against leptospirosis on frequency and days to recurrence of uveitis and progression of disease in horses with equine recurrent uveitis (ERU). ANIMALS: Forty-one horses with ERU. PROCEDURE: Horses were randomly assigned to experimental (vaccinated) or control groups. Vaccine containing six serovars of Leptospira or placebo was administered, an ophthalmic examination performed and blood samples drawn on days 0, 28, 180 and 365. Antibody titers were measured against each serovar. Recurrence of uveitis was verified by ophthalmic examination. Results of the initial and final ophthalmic examinations were compared and progression of disease defined as an increase in extent of synechiae, or development of new or progression of an existing cataract. RESULTS: Vaccination increased the average geometric mean serum antibody titer from 225 on day 0, to 4077 and 593 on days 28 and 180, respectively. After the second vaccination, days to first recurrence was significantly longer (median 126 days; range 24-231 days) when compared with controls (median 86 days; range 14-192 days, P=0.04). Recurrence of ERU was observed among 7/20 (35%) vaccinated horses and 12/21 (57%) controls; however, this difference was not statistically significant (P=0.061, OR 0.25, 95% CI 0.06, 1.07). More horses in the experimental group 13/20 (65%) experienced progression of disease when compared with controls 12/21(57%); however, this difference was statistically nonsignificant (P=0.35). CONCLUSIONS: Vaccine significantly increased days to recurrence, but failed to slow the progression of disease. These data do not support the use of vaccination against leptospirosis as adjunct therapy for the routine treatment of horses with ERU. 相似文献