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951.
Six dogs with partial seizures or partial seizure-like activity were treated with the antiepileptic drug felbamate between 1993 and 1998. All dogs had a history and results of diagnostic testing suggestive of either primary (idiopathic) or occult secondary epilepsy. Dogs ranged between four months and eight years of age at the onset of seizure activity. The median time period between onset of the first seizure and the start of felbamate therapy was 3.8 months (range 0.75 to 36 months). Median duration of therapy was nine months (range two to 22 months). All dogs experienced a reduction in seizure frequency after felbamate administration. Median total number of seizures post-treatment was two (range 0 to 9). Two dogs had an immediate and prolonged cessation of seizure activity. Steady-state trough serum felbamate concentrations measured at two weeks, and one, 12 and 22 months after the commencement of therapy in four dogs ranged between 13 and 55 mg/litre (median 35 mg/litre). Reversible haematological adverse effects were detected in two dogs, with one dog developing concurrent keratoconjunctivitis sicca. These results suggest that felbamate can be an effective antiepileptic drug without life-threatening complications when used as monotherapy for partial seizures in the dog.  相似文献   
952.
Cytokine gene expression in ileal tissues of cattle infected with Mycobacterium paratuberculosis was evaluated. The effects of infection with M. paratuberculosis on cytokine production may influence immune regulation at the site of colonization, resulting in the chronic inflammatory state associated with the latter stages of this disease. Ileal samples were obtained at necropsy from noninfected control cows (n=8) and clinically infected cows (n=7) and processed for immunohistochemistry and in situ hybridization. Cows infected with M. paratuberculosis were in the latter stages of disease with clinical signs such as weight loss, watery diarrhea, and inappetence. Among cytokines we studied, interleukin-1alpha (IL-1alpha), IL-1beta, IL-6, and interferon-gamma (IFN-gamma) were expressed significantly more in infected animals than in noninfected control animals. The expression of tumor necrosis factor-alpha (TNF-alpha), however, was not different between the two groups of cattle. In addition, immunohistochemical staining demonstrated that the number of resident macrophages in the ileum of infected animals was three times greater than that of noninfected cows. In contrast to this, ileal tissues from noninfected control animals contained 1.5 times more neutrophils than the ileal tissues from cows infected with M. paratuberculosis. These data demonstrate that localized ileal cytokine production is different between cows chronically infected with M. paratuberculosis and noninfected control cows.  相似文献   
953.
Referred cases (n = 375) of laryngeal paralysis (1985-1998) from a mixed-breed equine population included 351 (94%) cases of recurrent laryngeal neuropathy (RLN) (idiopathic laryngeal hemiplegia) and 24 cases (6%) of laryngeal paralysis from causes other than RLN. Laryngeal movements were classified endoscopically into one of 6 grades, in contrast to the usual 4 grades. The RLN cases had a median grade 4 laryngeal paralysis, of which 96% were left-sided, 2% right-sided and 2% bilaterally affected. RLN cases included 204 (58%) Thoroughbred, 96 (27%) Thoroughbred-cross, 23 (7%) draught, 16 (5%) Warmbloods and 10 (3%) other breeds, including only 4 (1%) ponies. The median age of RLN cases at referral was 6 years (range 2-12) and their median height was 170.2 cm. The work of RLN horses included National Hunt racing (42%), flat racing (1%), hunting (19%), eventing (16%) and miscellaneous work (22%). Reported presenting signs in RLN-affected horses included abnormal exercise-related respiratory sounds in 90% and reduced exercise tolerance in only 64%. However, many horses were referred before their exercise tolerance could be fully assessed. Forty percent of the RLN cases had intercurrent disorders, including 10% with additional upper respiratory and 7% with lower respiratory tract diseases. The 24 nonidiopathic RLN cases included 12 with bilateral laryngeal paralysis, 11 (92%) of which were ponies. Bilateral laryngeal paralysis occurred with hepatic encephalopathy in 7 cases and following general anaesthesia in 2 cases. The 12 cases of acquired unilateral laryngeal paralysis included 7 caused by guttural pouch mycosis.  相似文献   
954.
Protection of animals against respiratory infections has long been known to depend on respiratory mucosal immunity. However, few studies have been reported on the immune response following intranasal (i.n.) immunisation with non-living, soluble antigens. This study determined the kinetics of the humoral and cellular immune responses in calves after i.n. immunisation with Limulus haemocyanin (LH) with cholera toxin adjuvant, or subcutaneous (s.c.) immunisation with LH in incomplete Freund's adjuvant. A proliferative response of peripheral blood mononuclear cells cultured in vitro with LH was observed in animals immunised 7-10 days after i.n. and s.c. immunisations with no significant differences between the two immunised groups. LH -specific antibody was present in the serum of animals immunised s.c. (IgM, IgG1 and IgG2) and i.n. (IgA). Although significant IgA responses were observed, i.n. immunisations in cattle with soluble protein antigens and cholera toxin as an adjuvant did not induce a strong systemic immune response.  相似文献   
955.
A four-month-old male Labrador retriever was presented for polyuria, polydipsia and persistent euglycaemic glucosuria. On referral, diagnostic tests demonstrated abnormal fractional excretions of electrolytes, increased urinary excretion of selected amino acids, mild renal tubular acidosis and mild proteinuria, indicating renal tubular dysfunction. Pyelonephritis was suspected and potentiated amoxycillin was administered. On re-evaluation at six months of age, the dog was no longer polyuric or polydipsic and the metabolic abnormalities associated with the tubulopathy had resolved. Transient Fanconi's syndrome has not previously been reported in small animals. This report demonstrates the potential for recovery of function in cases presenting with renal tubulopathies.  相似文献   
956.
Chicken leptin: properties and actions   总被引:6,自引:0,他引:6  
Chicken leptin cDNA shows a high homology to mammalian homologous, with an expression localized in the liver and adipose tissue. It is noteworthy, that the hepatic expression is most likely associated with the primary role that this organ plays in lipogenic activity in avian species. As in mammals, chicken leptin expression is regulated by hormonal and nutritional status. This regulation is tissue-specific and with a high sensitivity in the liver compared to adipose tissue. The blood leptin levels are regulated by the nutritional state with high levels in the fed state compared to the fasted state. The recombinant chicken leptin markedly inhibits food intake as reported in mammals, suggesting the presence of an hypothalamic leptin receptor. The chicken leptin receptor has been identified and all functional motifs are highly conserved compared to mammalian homologous. Chicken leptin receptor is expressed in the hypothalamus but also in other tissues such as pancreas, where leptin inhibits insulin secretion and thus may have a key role in regulating nutrient utilization in this species.  相似文献   
957.
958.
One hundred and five donkeys were examined over a 12-month period for the presence of Gasterophilus spp. larvae in their stomachs. G. intestinalis and G. nasalis were found, but there was a distinct seasonal variation in their abundance. The numbers of second-stage larvae (L2) peaked during the early winter and early summer, but they were absent or at low levels during the early spring and early autumn. This suggests that there are two periods of adult fly activity (late autumn and late spring) for both G. nasalis and G. intestinalis. Third-stage larvae (L3) were found throughout the year, but the lowest levels were seen in the late summer and autumn. The parasites also had an aggregated distribution, which may be due to host selection by the fly. The numbers of larvae did not vary significantly with age, which may be due to a lack of acquired protective immunity or to tolerance after repeated exposure.  相似文献   
959.
The data from 20 dogs with histopathologically confirmed granulomatous meningoencephalomyelitis were reviewed in an attempt to identify clinical signs and morphological and cellular parameters, particularly the infiltration of mast cells, which might be associated with the clinical course of the disease. Thirteen of the dogs had the acute form of the disease and seven had the chronic form. Young to middle-aged, small breed female dogs were over-represented. Central vestibular signs were observed in six of the dogs with the acute disease. Analyses of cerebrospinal fluid revealed moderate to severe pleocytosis and high protein concentrations in all cases. Histopathological investigations revealed disseminated perivascular cuffs, large confluent granulomata, tissue necrosis, infiltration with neutrophils and a large number of mitotic cells in the dogs with either of the clinical forms of the disease. Tryptase-positive mast cells were observed in all the cases, but there were significantly larger numbers in the dogs with the acute form.  相似文献   
960.
OBJECTIVE: To evaluate the efficacy and tolerance of a treatment protocol for obsessive-compulsive disorder, separation anxiety and noise phobia in dogs. DESIGN: A study was undertaken to assess clinical responses in 24 dogs diagnosed with one or more of three behavioural disorders stated above to a treatment regimen that included clomipramine and behaviour modification. PROCEDURE: A detailed behavioural and clinical history was obtained for each dog. Obsessive-compulsive disorder was diagnosed in nine cases: primary presenting complaints were tail-chasing, shadow-chasing, circling and chewing; one case was diagnosed with concurrent separation anxiety. Separation anxiety was diagnosed in 14 cases: presenting complaints included destruction, vocalisation and escaping in the absence of the owner; four cases also exhibited noise phobia. The study also included one dog diagnosed with noise phobia only and another with inappropriate fear responses. Clomipramine was administered orally twice daily. The starting dose was 1 to 2 mg/kg bodyweight. The dose was increased incrementally to a maximum of 4 mg/kg if needed. A behaviour modification program was designed and the owner instructed on its implementation. Dogs continued medication for at least 1 month after clinical signs disappeared or were acceptably reduced, then withdrawal of medication was attempted by decreasing drug dosage at weekly intervals while behaviour modification continued. RESULTS: The presenting clinical sign was largely improved or disappeared in 16 dogs, 5 demonstrated slight to moderate improvement and the behaviour was unchanged in 3. Clomipramine withdrawal was attempted in nine cases: this was successful in five. CONCLUSION: Clomipramine was effective and well-tolerated in controlling signs of obsessive-compulsive disorder and/or separation anxiety and/or noise phobia in 16 of 24 assessable cases, when used in combination with behaviour modification, and improvement in clinical signs was noted in 5 others.  相似文献   
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