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231.
K A Roby J Beech J C Bloom M Black 《Journal of the American Veterinary Medical Association》1990,196(3):465-467
A yearling Arabian-type filly with a history of poor growth, erythrocytosis, hypoglycemia, and high liver enzyme activities was admitted to the hospital for evaluation. Three days after admission, the filly collapsed, deteriorated rapidly despite treatment, and was euthanatized. A metastatic hepatocellular carcinoma with capsular rupture and hemoperitoneum were found at necropsy. Primary liver tumors are rare in horses, and hepatocellular carcinoma has been reported in only 1 other horse. The systemic manifestations of the tumor in this filly included weakness, weight loss, inappetence, erythrocytosis with tumor production of erythropoietin, persistent hypoglycemia with normal serum insulin concentrations, serum alpha-fetoprotein (normally present only during fetal life), and terminal massive hemoperitoneum, all features of the syndrome in man. 相似文献
232.
Between 1983 and 1989, we examined 1,201 aborted fetuses and dead lambs from the north central United States. Toxoplasmosis was diagnosed in 17.5%, campylobacteriosis in 9.9%, chlamydiosis in 4.7%, and miscellaneous infections in 15.1%. Inflammatory lesions suggestive of infectious causes were seen in 13%. Noninfectious causes were identified in 6.1%, and a diagnosis was not reached in 33.3%. An agglutination test was used to detect Toxoplasma gondii-specific antibodies in ovine fluids. Toxoplasma gondii antibodies were detected in 223 of 1,064 (20.9%) fluids from fetuses and dead lambs. Of 201 seropostive (greater than or equal to 16) fetuses and lambs, T gondii antibody titers (reciprocal) were 16 (21 fetuses and lambs), 32 (10 fetuses and lambs), 64 (2 fetuses and lambs), 128 (7 fetuses and lambs), 256 (9 fetuses and lambs), 512 (5 fetuses and lambs), 1,024 (15 fetuses and lambs), 2,048 (13 fetuses and lambs), 4,096 (13 fetuses and lambs), 8,196 (13 fetuses and lambs), 16,392 (19 fetuses and lambs), and greater than or equal to 32,784 (74 fetuses and lambs). 相似文献
233.
Gastric dilatation-volvulus (GDV) is a dramatic and enigmatic disease of large and giant breed dogs characterised by the rapid accumulation of gas in the stomach. This causes gastric dilatation, twisting of the stomach about its long axis, compression of surrounding organs, hypovolaemic and cardiogenic shock, and if untreated, death. It has been estimated that the disease afflicts approximately 60,000 dogs in the USA each year with a mortality rate ranging from 7 to 60 per cent depending on accessibility to adequate veterinary care. The cause is unknown. While diet was at one time believed to be associated with the genesis of the disease, critical review of available data provides no evidence to support this hypothesis. A variety of predisposing or risk factors have been identified but none is suspected of being the cause, indeed, the disorder may have a multiple aetiology. Current thinking suggests that the final common pathway in the development of GDV may be an inhibition of gastric motility and emptying. This could come about through a primary disruption of normal gastric electrical patterns or through the effect of extraneous stressful events that disrupt gastric motility. After dilatation a series of potentially lethal events is unleashed which include compression of the caudal vena cava, pooling of blood in the microcirculation of the viscera and hindlimbs, metabolic acidosis, gastric necrosis, cardiac arrhythmias, disseminated intravascular coagulation, hypotensive and cardiogenic shock and death. Nevertheless, even advanced cases can survive if treated appropriately. If the cause could be identified logical prophylaxis might follow. Studies at the University of Florida have failed to demonstrate any effect of diet on gastric function in large breed dogs, suggesting that diet is probably not the cause of the disease. Researchers at Colorado State University also found no association with diet in clinical patients. Recent studies at the University of Florida have revealed distinct abnormalities in gastric electrical activity in GDV patients. In human patients these abnormalities, called dysrhythmias, have been associated with gastric distention, bloating, delayed emptying, nausea and retching. Unfortunately, dysrhythmias are also present, albeit to a lesser degree, in experimental GDV. These findings leave unanswered the question as to whether abnormalities in gastric motility play a role in the genesis of GDV. 相似文献
234.
Extrahepatic biliary atresia in a border collie 总被引:2,自引:0,他引:2
Schulze C Rothuizen J van Sluijs FJ Hazewinkel HA van den Ingh TS 《The Journal of small animal practice》2000,41(1):27-30
Progressive lameness and leg pain were the predominant clinical signs in a 17-week-old male border collie presented for examination. On clinical investigation, extrahepatic cholestasis in association with rickets due to inadequate vitamin D resorption was diagnosed. The dog was treated parenterally with vitamin D and a cholecystoduodenostomy was performed. At 25 days postsurgery the lameness had resolved and bone structure was radiographically normal. However, at six weeks postsurgery, the dog's condition deteriorated rapidly and euthanasia was finally performed at eight weeks postsurgery. At postmortem examination, Toxocara canis nematodes were found to have invaded the biliary system via the anastomosis between the gallbladder and duodenum, causing biliary and hepatic toxocariasis. The cause of the primary extrahepatic cholestasis was atresia of the common bile duct at the hepatic end. The liver tissue showed microscopic lesions of chronic extrahepatic cholestasis as well as acute inflammation associated with the nematode invasion. There was no postmortem evidence of bone lesions. Extrahepatic biliary atresia is extremely rare in animals and has not been described before in dogs. In contrast, it represents the most common cause of congenital cholestasis in children, occurring in approximately one per 10,000 to 15,000 live births. 相似文献
235.
Effects of human recombinant interleukin-1beta on canine articular chondrocytes in three-dimensional culture 总被引:1,自引:0,他引:1
Cook JL Anderson CC Kreeger JM Tomlinson JL 《American journal of veterinary research》2000,61(7):766-770
OBJECTIVE: To determine the effects of interleukin (IL)-1beta on matrix synthesis and degradation by chondrocytes cultured in a 3-dimensional (3-D) gel medium. SAMPLE POPULATION: Chondrocytes from 7 dogs. PROCEDURE: Articular chondrocytes were harvested and cultured in 3-D gel medium alone or with 10 or 20 ng IL-1beta/ml that was added beginning on day 0, 3, 6, or 9. On days 3, 6, 12, and 20 of 3-D culture, samples of the liquid medium were evaluated for glycosaminoglycan (GAG), prostaglandin E2 (PGE2), and matrix metalloprotease (MMP)-3 content. The 3-D plug in each well was evaluated for histologic characteristics of viability, cell morphology, and proteoglycan staining, immunohistochemically stained for collagen type II, and spectrophotometrically analyzed for GAG content. RESULTS: Significant differences for all variables were detected between controls and each IL-1beta group, among groups with different IL-1beta concentrations, and among groups with IL-1beta added at various time points. Chondrocytes exposed to IL-1beta had loss of GAG, increased PGE2 and MMP-3 concentrations, and lack of collagen type-II synthesis. These IL-1beta effects appeared to be time and concentration dependent. CONCLUSIONS: Addition of IL-1beta to chondrocytes in 3-D gel medium results in time- and concentration-dependent effects on matrix synthesis and degradation and provides an appropriate in vitro model for many of the pathophysiologic events associated with osteoarthritis. 相似文献
236.
Uboh CE Soma LR Luo Y McNamara E Fennell MA May L Teleis DC Rudy JA Watson AO 《American journal of veterinary research》2000,61(7):811-815
OBJECTIVE: To compare the pharmacokinetics of penicillin G and procaine in racehorses following i.m. administration of penicillin G procaine (PGP) with pharmacokinetics following i.m. administration of penicillin G potassium and procaine hydrochloride (PH). ANIMALS: 6 healthy adult mares. PROCEDURE: Horses were treated with PGP (22,000 units of penicillin G/kg of body weight, i.m.) and with penicillin G potassium (22,000 U/kg, i.m.) and PH (1.55 mg/kg, i.m.). A minimum of 3 weeks was allowed to elapse between drug treatments. Plasma and urine penicillin G and procaine concentrations were measured by use of high-pressure liquid chromatography. RESULTS: Median elimination phase half-lives of penicillin G were 24.7 and 12.9 hours, respectively, after administration of PGP and penicillin G potassium. Plasma penicillin G concentration 24 hours after administration of penicillin G potassium and PH was not significantly different from concentration 24 hours after administration of PGP. Median elimination phase half-life of procaine following administration of PGP (15.6 hours) was significantly longer than value obtained after administration of penicillin G potassium and PH (1 hour). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that i.m. administration of penicillin G potassium will result in plasma penicillin G concentrations for 24 hours after drug administration comparable to those obtained with administration of PGP Clearance of procaine from plasma following administration of penicillin G potassium and PH was rapid, compared with clearance following administration of PGP. 相似文献
237.
A 14-year-old Thoroughbred gelding with a history of acute onset of hematuria was presented for necropsy. Transitional cell carcinoma of the urinary bladder with intra-abdominal dissemination was diagnosed. Tumor masses were observed on the splenic capsule and surrounding the distal abdominal aorta. Tumor cells showed diffuse cytoplasmic reactivity for cytokeratin but were negative for epithelial membrane antigen, carcinoembryonic antigen, tumor-associated glycoprotein 72, and vimentin. 相似文献
238.
239.
J. E. ILKIW C. M. SUTER D. McNEAL T. B. FARVER E. P. STEFFEY 《Journal of veterinary pharmacology and therapeutics》1996,19(3):217-224
The effects of intravenous administration of variable-dose midazolam and ketamine (3 mg/kg) were studied in twelve healthy unmedicated cats from time of administration until full recovery. A range of midazolam doses (0.0, 0.05, 0.5, 1.0, 2.0 and 5.0 mg/kg) was chosen, so that beneficial and/or detrimental effects could be documented and the therapeutic window for further study determined. One minute after administration of ketamine, all cats had assumed a lateral position, mostly with head up. Muscle tone was increased (100%), apneustic breathing pattern evident in 92% of cats, chewing without stimulation of the oropharyngeal area was observed in most cats (97%), but most cats did not salivate (87%). At 2.5 min after completion of ketamine injection and 1 min after administration of saline, a similar picture was observed, except that salivation was evident. All cats chewed or swallowed in response to a finger or laryngoscope placed in the oropharyngeal area and, while most cats were not aware of a noxious stimulus to the tail, some cats were aware of a noxious stimulus to the paw. Recovery from ketamine alone was rapid and smooth with cats rolling into sternal recumbency and then cautiously walking with ataxia. Recovery to walking without incoordination was also rapid (< 2 h) and no abnormal behavioural patterns were observed during recovery. Administration of midazolam after ketamine, had beneficial effects and the therapeutic window for midazolam was found to lie between 0.05 mg/kg and 0.5 mg/kg. Administration of any dose of midazolam after ketamine caused a greater proportion of cats to assume a laterally recumbent position with head down compared with ketamine alone, however, the time period of recumbency was only significantly longer with a midazolam dose of 2.0 mg/kg or above. Doses of midazolam of 0.5 mg/kg or above decreased muscle rigidity but did not affect salivation or respiratory pattern observed in cats which received ketamine alone. A significantly greater proportion of cats which received ketamine and midazolam 0.5 mg/kg or above did not swallow in response to a finger or a laryngoscope placed in the mouth compared with that which received ketamine alone. The length of time in which cats did not swallow was only significantly longer at midazolam doses of 1.0 mg/kg and above. At midazolam doses of 0.5 mg/kg or above, the proportion of cats without a nociceptive response to a tail or paw clamp was significantly greater than cats which received ketamine alone. The time period without nociceptive response, however, was not influenced by midazolam administration. The time taken for cats which received ketamine and midazolam 0.05 mg/kg or 0.5 mg/kg to assume sternal position, walk with ataxia, walk without ataxia, behave normally when approached or restrained and recover normal arousal state was not significantly different from cats which received ketamine alone. Ketamine and midazolam 5.0 mg/kg significantly prolonged all recovery times compared with ketamine alone. Unfortunately, a greater proportion of cats which received ketamine and midazolam 0.5 or 5.0 mg/kg exhibited detrimental behavioural effects. These were more likely to be adverse and included restlessness, vocalization and difficulty approaching and restraining cats. In this study, an 相似文献
240.
This survey assessed the feline transfusion practices at the University of Berlin from 1998 to 2001 in regard to patient population, indications, efficacy, and transfusion reactions. Blood was obtained from seven healthy in-house donors and 127 mostly indoor client-owned pet cats. Over a 3-year period 91 cats were transfused with blood type compatible blood. The blood was fresh (within 8 h of collection) or stored no longer than 15 days. Transfusions were required because of blood loss anaemia (n=40), haemolytic anaemia (n=13), ineffective erythropoiesis (n=35), hypoproteinaemia (n=2) or coagulopathy (n=2). The anaemic cats had a pretransfusion haematocrit of 5-20% (m [median]=13), and received one to six transfusions (m=1). The survival rates of the anaemic cats at 1 and 10 days after transfusion were 84 and 64%, respectively. None of the deaths appeared to be related to transfusion reactions. The major crossmatch, undertaken before 117 transfusions, was incompatible for eight cats. All except for one had previously been transfused. Lysis of transfused cells in six cases resulted in a less than expected haematocrit rise and an increase in serum bilirubin. Transient mild transfusion reactions were only noted in two cats during the second or third transfusion. In conclusion, with proper donor selection and appropriate compatibility screening, blood transfusions are well tolerated, appear effective, and may increase chances of survival. 相似文献