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991.
992.
A clinical trial was conducted to investigate the animal safety of a progesterone-releasing intravaginal device (PRID). Anestrus cows at a mean of 63 +/- 3.5 d in milk were randomly assigned to an ovulation-synchronization protocol that included placement of either a PRID or a placebo intravaginal device (PID) or no such treatment. At enrolment and at device removal 7 d later, blood samples were collected. The outcomes of interest included the vaginal reaction to the device, the vaginal mucosal integrity, and the results of bacterial culture of swabs of the vaginal mucosa. In addition, the leukocyte and haptoglobin responses were measured. Although only 5% of the PRID-treated animals compared with 19% of the PID-treated animals had a copious purulent vaginal discharge at the time of device removal, there was no significant difference in the proportions; furthermore, there was no evidence of vaginal mucosal damage associated with either device. The total blood leukocyte count was significantly lower in both the PRID-treated cows and the PID-treated cows after device removal compared with the start of treatment (P < 0.05) and compared with no treatment (P < 0.001); there was no difference in leukocyte response between the 2 device-treated groups. The decrease in leukocyte count was attributed to a significant reduction in the numbers of circulating neutrophils and lymphocytes, a pattern consistent with the luteal phase of the bovine estrus cycle. There was no significant difference in the circulating haptoglobin concentration between the 3 groups of cows. Culture revealed commensal bacterial growth in the vagina of all the cows.  相似文献   
993.
In vitro cross-reactivity among two house dust (Dermatophagoides farinae, D. pteronyssinus) and three storage (Acarus siro, Tyrophagus putrescentiae, Lepidoglyphus destructor) mites was examined in 20 mite-sensitive dogs with natural occurring atopic dermatitis (group A), 13 high-IgE beagles experimentally sensitized to D. farinae (group B), and five healthy beagles (group C). Intradermal testing (IDT) and serology for allergen-specific IgE demonstrated that co-sensitization for all possible pairs of the five mites was generally 45% or higher among group A dogs. In the same dogs, enzyme-linked immunosorbent assay cross-inhibition results indicated that each one of D. farinae, A. siro and T. putrescentiae was a strong inhibitor of all the remaining mites, whereas D. pteronyssinus was a strong inhibitor of L. destructor. A high number of positive IDT and serology test results for D. pteronyssinus, A. siro, T. putrescentiae and L. destructor were recorded among group B dogs. No conclusive evidence of exposure to these mites was found upon analysis of dust samples from their environment and their food for the presence of mites and guanine. Also, the number of positive test results was generally higher among group B than among group C dogs. Enzyme-linked immunosorbent assay cross-inhibition revealed that D. farinae was a strong inhibitor of D. pteronyssinus, A. siro and T. putrescentiae. Collectively, these results demonstrated extensive in vitro cross-reactivity among house dust and/or storage mites that can explain false-positive results upon testing of dust mite-sensitive dogs with atopic dermatitis.  相似文献   
994.
OBJECTIVE: To determine the effects of training and sustained submaximal exercise on hematologic values in racing sled dogs. DESIGN: Cohort study. ANIMALS: 39 Alaskan sled dogs bred for endurance racing. Procedures-Blood samples were collected prior to initiation of a 7-month training regimen (n=39), after completion of the training regimen (19), and after completion of an 1,100-mile race (9), and a CBC, differential cell count, and flow cytometry for leukocyte surface antigens were performed. RESULTS: Both training and exercise caused significant decreases in PCV and hemoglobin concentration and significant increases in total WBC count. In contrast, training and exercise were not found to have significant effects on absolute numbers or fractions of CD4+ or CD8+ lymphocytes, other than a significant increase in the fraction of CD8+ lymphocytes associated with training. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that training and exercise induced changes in several hematologic values in racing sled dogs. Extracellular fluid volume expansion was the likely explanation for the training-induced decrease in PCV, and acute blood loss secondary to gastrointestinal tract bleeding was likely responsible for the decrease in PCV associated with acute exercise.  相似文献   
995.
Objective-To evaluate endoscopic liver biopsy and compare that technique with a standard coeliotomy biopsy technique in fish. Design-Randomized controlled clinical trial. Animals-30 channel catfish (Ictalurus punctatus). Procedures-10 fish were randomly assigned into control, coeliotomy, and coelioscopy groups. Anesthesia was performed with a recirculating anesthesia machine. Body weight, PCV, and total protein (TP) concentration in blood as well as plasma activities of aspartate aminotransferase, creatinine phosphokinase, lactate dehydrogenase, and sorbitol dehydrogenase were measured before and after surgery. Standard ventral coeliotomy or coelioscopy was performed, and the biopsy specimens were scored histologically. Results-Coeliotomy and coelioscopy procedures were well tolerated without acute deaths. Blood TP concentration and PCV decreased after surgery in the coelioscopy group because of intracoelomic fluid administration to aid visualization. Minor changes in activities for hepatic and muscular enzyme activities were apparent, but were not significantly different between the coelioscopy and coeliotomy groups. Coelioscopy and coeliotomy yielded biopsy specimens of similar diagnostic quality. However, coelioscopy permitted a more extensive evaluation of the viscera, and all 10 surgical wounds healed completely, compared with severe wound dehiscence in 3 of 10 fish that underwent coeliotomy. Conclusions and Clinical Relevance-Both coelioscopy and coeliotomy were capable of yielding antemortem liver biopsy specimens of diagnostic quality in catfish. Coelioscopy permitted a more detailed examination of the coelomic viscera through a smaller surgical incision, was less traumatic, and resulted in decreased wound dehiscence.  相似文献   
996.
997.
998.
A 4-year-old, neutered male Domestic Shorthair cat with a history of depression, anorexia, and weight loss was diagnosed with acute myelogenous leukemia (AML). The cat tested positive by both the feline immunodeficiency virus antibody test and feline leukemia virus enzyme-linked immunosorbent assay test. Results of cytochemical stains on peripheral blood and bone marrow specimens indicated acute myeloid leukemia with unusual basophilic differentiation (AML, M-2B).  相似文献   
999.
Previously published studies have neither used nor reported the results of an indirect enzyme-linked immunosorbent assay (iELISA) to measure serologic responses in natural outbreaks of strangles. The concept of using serologic responses to identify persistent carriers of Streptococcus equi has been proposed but not scientifically evaluated. The specific aims of the current study were to determine the duration and level of truncated fibrinogen-binding protein-specific (SeM allele 1) antibody production in ponies involved in a natural outbreak of strangles and to determine if test results from this serologic iELISA could predict persistent carrier status. Serologic samples were obtained before and after an outbreak of naturally occurring strangles infection. Persistent carriers of S. equi were identified via culture and polymerase chain reaction (PCR) testing of lavage fluid collected from the guttural pouches and nasopharynx or swabs of the nasopharynx after recovery from acute disease and at postmortem examination. Logistic regression analysis was used to determine if an association existed between serologic response and persistent carrier state. The ELISA reported in the current study definitively confirmed a recent exposure to S. equi. However, the measured serologic response did not predict carrier status in this strangles outbreak. Therefore, a guttural-pouch endoscopy with subsequent culture or PCR testing to detect S. equi remains the most accurate method available for the identification of persistent carriers.  相似文献   
1000.
Because of the shortage of human skin for research purposes, porcine skin has been used as a model of human skin. The aim of this study was to identify the region of German Landrace pig skin that could be used as the best possible substitute for human abdominal skin. Porcine samples were collected from the ear, flank, back and caudal abdomen; human abdominal skin samples were excised during plastic surgery. Histological and ultrastructural assessments were carried out on the epidermis and dermis, with emphasis on the dermo‐epidermal interface length, dermo‐epidermal thickness ratio as well as densities of; hair follicles, arrector pili muscles, blood vessels and sweat glands. In the pig, the barrier function of the four anatomical regions was assessed. Results showed that both histologically and ultrastructurally, all four regions of porcine skin were similar to human skin. These include the shapes of keratinocytes, structure of cell contacts and presence of Weibel Palade bodies in endothelial cells. Other parameters such as the thickness of epidermis, the thickness of stratum basale, spinosum and granulosum and the number of cell layers in the stratum corneum were similar in human abdominal and in all four regions of porcine skin. However, there were also significant differences especially in the thickness of the stratum corneum, the dermo‐epidermal interface length and the blood vessel density.  相似文献   
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