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951.
Over the last 20 years, ultrasound has become a useful diagnostic tool in veterinary medicine. The purpose of this study was to use ultrasonographic examinations to determine if intra-abdominal contents could be visualized. Nineteen dogs, ranging from 8 months to 18 years of age were included. Each animal was evaluated sonographically prior to surgery, 24 h after surgery, and then 2-6 weeks following the surgical procedure. The results of our study suggest that ultrasound is an effective means for evaluation of the abdomen and surgery site following surgery. Both the abdomen and surgery site were clearly visualized in all dogs. In addition, subjective evaluation of the intra-abdominal contents was performed. The limiting factor in this study was not the presence of air, as was expected. Rather the limiting factor for appropriate visualization was pain. The information obtained could prove to be useful to surgeons and radiologists in assessing a patient's status postoperatively.  相似文献   
952.
During the spring and summer of 2001 and in association with the mare reproductive loss syndrome, 22 terminal and 12 clinical cases of equine pericarditis were diagnosed in central Kentucky. Actinobacillus species were the principal isolates from 8 of 10 nontreated, terminally affected and 3 of 10 clinically affected horses. Enterococcus faecalis and Streptococcus zooepidemicus were cultured from the remaining 2 nontreated terminal cases. No viruses were isolated in tissue culture. Nucleic acid of equine herpesvirus-2 was detected in pericardial and tracheal wash fluids of 3 and 1 individuals, respectively. Microscopic alterations in sections of heart and parietal pericardium were consistent with chronic fibrinous bacterial pericarditis. This report confirms a significant role of Actinobacillus species in equine pericarditis and describes an epidemic of this infrequently observed syndrome in the horse.  相似文献   
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954.
OBJECTIVE: To determine effects of lipoic acid, vitamin E, and cysteine before and after oxidant challenge in cats. ANIMALS: 24 sexually intact adult cats. PROCEDURE: Cats were allocated into 4 equal groups. For 25 weeks, group A was fed a control dry diet and groups B, C, and D received this diet supplemented with vitamin E (2200 U/kg [dry matter basis {DMB}]) plus cysteine (9.5 g/kg [DMB]), lipoate (150 mg/kg [DMB]), or all 3 antioxidants together, respectively. Weights were measured every 3 days and venous blood obtained every 5 weeks for CBC; serum biochemical analyses; lymphocyte blastogenesis; thiobarbituric acid reactive substances concentration; and concentrations of plasma protein carbonyl, 8-OH d-guanosine, blood glutathione, plasma amino acid, lipoate, and dihydrolipoate. At 15 weeks, all cats received acetaminophen (9 mg/kg, PO, once), clinical effects were observed, and methemoglobin concentrations were measured. RESULTS: Lymphocyte blastogenesis increased transiently in group C and D cats. After acetaminophen administration, all groups had transient increases in methemoglobin within 4 hours and mild, brief facial edema; group C had decreased glutathione concentration and increased 8-OH d-guanosine concentration versus controls; and protein carbonyl concentration increased least for group B. Plasma lipoate and dihydrolipoate concentrations peaked by week 10 for groups C and D. Conclusions and Clinical Relevance-Lipoate, vitamin E, and cysteine did not have synergistic effects. Lipoate supplementation (150 mg/kg [DMB]) did not act as an antioxidant but appeared to enhance oxidant effects of acetaminophen. Vitamin E plus cysteine had protective effects.  相似文献   
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957.
The role of CD4+CD25+ regulatory T cells in viral infections   总被引:5,自引:0,他引:5  
Many virus infections result in the suppression of one or more functions of the immune system. Multiple mechanisms have been proposed to explain viral-induced immunosuppression, including an imbalance in the cellular Th1/Th2 or cytokine profile, induction of anergy, depletion of effector cells and most recently the activation of CD4+CD25+ regulatory T (T reg) cells. CD4+CD25+ T reg cells are a subset of circulating CD4+ T cells with suppressive properties. CD4+CD25+ T reg cells were first identified in mice as cells capable of maintaining self-tolerance by suppressing autoreactive T cells. This review focuses on interactions between CD4+CD25+ T reg cells and viral pathogens. Most cases in which CD4+CD25+ T reg cells participate in response to infection reported so far involve chronic or persistent viral infections. Examples have been growing recently and include members of different viral families including retroviridae, herpesviridae and picornaviridae. It is currently not known how microbes are recognized by CD4+CD25+ T reg cells and whether exoantigen-specific T reg cells are of the same lineage as self-reacting natural T reg cells or represent peripherally induced counterparts derived from CD4+CD25- T cells. The findings that T reg cells influence the functional immunity during viral infections, however, might indicate that, in some cases, virus-specific T reg cells not only influence immune pathology or prevent pathogen elimination but also can promote a generalized state of immunosuppression in vivo such that the host is more susceptible to secondary infections with other pathogens or has reduced resistance to tumors. Conceivably, the activities of T reg cells might be one of the contributing reasons why it has been difficult so far to produce effective vaccines against some persisting viral infections.  相似文献   
958.
The cardiac biomarkers cardiac troponin T (cTnT) and I (cTnI) and the cardiac isoenzyme of creatine kinase (CKMB) are used extensively in human medicine to diagnose and provide valuable prognostic information in patients with ischemic, traumatic, and septic myocardial injury. We designed a study to establish normal values for these markers in healthy, neonatal foals and to compare them with values obtained from septic neonates in a referral hospital population. The 25th, 50th, 75th, and 95th percentiles for cTnI and CKMB in the healthy-foal population were 0.08, 0.14, 0.25, 0.49 ng/mL and 1.4, 2.3, 4.0, 7.4 ng/mL, respectively. The values obtained for cTnT were frequently (43/52 foals; 83%) below the lower limit of detection of the assay (0.009 ng/mL), but the median and range were 0.009 and 0.009-0.041 ng/mL, respectively. In the septic foal population, the 25th, 50th, 75th, and 95th percentile values for cTnI and CKMB were 0.05, 0.12, 0.22, and 1.10 ng/mL and 2.0, 4.4, 7.8, and 24 ng/mL, respectively. The values obtained for cTnT were less frequently below the lower limit of detection (23/38 foals; 60%) compared with the healthy foal population, and the median and range were 0.009 and 0.009-0.20 ng/mL, respectively. Significantly higher values were observed for cTnT and CKMB in septic foals compared with the healthy neonatal foal population, but there were no differences among septic foals in survivors compared with nonsurvivors. These findings suggest that myocardial injury occurs during septicemia in neonatal foals but that the injury is not associated with survival among septic foals.  相似文献   
959.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are used to control acute and chronic pain as well as to manage oncologic and neurologic diseases in human and veterinary patients. Despite ongoing research and efforts to improve the safety and efficacy of existing drugs, adverse effects such as gastrointestinal irritation, renal and hepatic toxicity, interference with hemostasis, and reproductive problems persist. The true incidence of NSAID-induced adverse effects in animals is unknown, but is likely underestimated, because cats and dogs may be more sensitive than humans to NSAIDs due to alterations in drug metabolism, absorption, and enterohepatic recirculation. NSAIDs produce both analgesia and toxic adverse effects primarily by inhibiting cyclooxygenase (COX), thereby decreasing the production of prostaglandins that signal inflammation and pain as well as mediate physiologic functions such as platelet aggregation, gastric protection, and electrolyte balance in the kidney. The presence of at least 2 COX isoforms may account for variability in NSAID efficacy and toxicity both within and among species. This paper reviews and evaluates the published literature on the safety, pharmacology, uses, and complications of a subclass of COX-1-sparing drugs, the coxibs, in veterinary medicine. Coxibs and other COX-1-sparing drugs provide a clinically useful improvement over traditional NSAIDs, but data are incomplete and more in vivo species-specific, target-tissue, and clinical studies are needed.  相似文献   
960.
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