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Tydén, E., Bj?rnstr?m, H., Tjälve, H., Larsson, P. Expression and localization of BCRP, MRP1 and MRP2 in intestines, liver and kidney in horse. J. vet. Pharmacol. Therap. doi: 10.1111/j.1365‐2885.2009.01140.x. The gene and protein expression and the cellular localization of the ABC transport proteins breast cancer resistance protein (BCRP), multidrug resistance‐associated protein 1 (MRP1) and multidrug resistance‐associated protein 2 (MRP2) have been examined in the intestines, liver and kidney in horse. High gene and protein expression of BCRP and MRP2 were found in the small intestines, with cellular localization in the apical membranes of the enterocytes. In the liver, MRP2 was present in the bile canalicular membranes of the hepatocytes, whereas BCRP was localized in the cytoplasm of hepatocytes in the peripheral parts of the liver lobuli. In the kidney both BCRP and MRP2 were predominantly present in the distal tubuli and in the loops of Henle. In most tissues, the gene and protein expression of MRP1 were much lower than for BCRP and MRP2. Immunostaining of MRP1 was detectable only in the intestines and with localization in the cytoplasm of enterocytes in the caecum and colon and in the cells of serous acini of Brunner’s glands in the duodenum and the upper jejunum. The latter cells were also stained for BCRP, but not for MRP2. Many drugs used in horse are substrates for one or more of the ABC transport proteins. These transporters may therefore have important functions for oral bioavailability, distribution and excretion of substrate compounds in horse.  相似文献   
995.
This report describes a case of cutaneous pythiosis in a 6‐year‐old female mixed breed dog, from the central west region of São Paulo State, Brazil. The cytological and histopathological analyses showed an intense inflammatory infiltrate with presence of numerous hyphal elements, suggesting infection due to Pythium insidiosum. The diagnosis was confirmed by nested‐PCR, which was carried out with specific primers derived from the ribosomal DNA region. The pathogen occurs in Brazil and veterinarians should be aware of the importance of correctly diagnosing this disease and differentiating it from other fungal diseases.  相似文献   
996.
A 4‐year‐old Welsh pony crossbred gelding was examined for acute onset of blepharospasm, epiphora and corneal oedema. Ophthalmic examination identified 2 conjunctival plaques located near the superior limbus of the left eye. The plaques did not resolve following treatment with topical triple antibiotic ointment, topical atropine ointment and oral flunixin meglumine and therefore a conjunctival biopsy was performed. Histology of the biopsy resulted in a diagnosis of eosinophilic conjunctivitis, which was treated with a topical corticosteroid ointment. Plaques resolved after 73 days of therapy but lesions did not improve with concurrent treatment with anthelmintics early in the course of therapy. Failure to identify an aetiological agent led to a diagnosis of idiopathic eosinophilic conjunctivitis. The conjunctival plaques have not recurred in the 10 months following discontinuation of therapy.  相似文献   
997.
Background: Omeprazole and famotidine both reduce severity of exercise‐induced gastritis, but administering famotidine is easier than administering omeprazole during racing competition. Hypothesis: Famotidine is more efficacious than no treatment in reducing severity of exercise‐induced gastritis; and high‐dose famotidine is more efficacious than omeprazole in reducing severity of exercise‐induced gastritis. Animals: Experiment 1: Randomized placebo‐controlled study, 36 sled dogs (3–8 years); Experiment 2: Randomized positive‐control study, 52 sled dogs (2–8 years). Methods: Experiment 1: Equal numbers of dogs randomly assigned to famotidine (20 mg q24h) or no treatment groups. Gastroscopy was performed 24 hours after the dogs ran 330 miles. Mucosal appearance was blindly scored by previously described scoring system. Experiment 2: Equal numbers of dogs randomly assigned to omeprazole (20 mg q24h) or high‐dose famotidine (40 mg q12h) groups. Gastroscopy was performed 48 hours before and 24 hours after the dogs ran 300 miles. Mucosal appearance was blindly scored by previously described scoring system. Results: Famotidine reduced the prevalence of clinically relevant, exercise‐induced gastric lesions compared with no treatment (7/16 versus 11/16, P= .031). Compared with high‐dose famotidine, omeprazole significantly decreased the severity (0.4 versus 1.2, P= .0002) and prevalence (2/23 versus 7/21, P= .049) of gastric lesions. Conclusions and Clinical Relevance: Although famotidine provides some benefit in the prevention of exercise‐induced gastric lesions, omeprazole is superior to famotidine in preventing gastritis in dogs running 300 miles. Routine administration of omeprazole is recommended to prevent stress‐associated gastric disease in exercising and racing Alaskan sled dogs.  相似文献   
998.
Background: Release of myelin basic protein (MBP) into the cerebrospinal fluid (CSF) is associated with active demyelination and correlates with outcome in various neurological diseases. Hypothesis/Objectives: To describe associations among CSF MBP concentration, initial neurological dysfunction, and long‐term ambulatory outcome in dogs with acute thoracolumbar intervertebral disk herniation (IVDH). Animals: Five hundred and seventy‐four dogs with acute thoracolumbar IVDH and 16 clinically normal dogs. Methods: Prospective case series clinical study. Signalment, initial neurological dysfunction as determined by a modified Frankel score (MFS), and ambulatory outcome at >3‐month follow‐up were recorded. Cisternal CSF MBP concentration was determined by an ELISA. Associations were estimated between CSF MBP concentration and various clinical parameters. Results: Dogs with thoracolumbar IVDH that did not ambulate at follow‐up had a higher CSF MBP concentration (median, 3.56 ng/mL; range, 0.59–51.2 ng/mL) compared with control dogs (median, 2.22 ng/mL; range, 0–3.82 ng/mL) (P= .032). A CSF MBP concentration of ≥3 ng/mL had a sensitivity of 78% and specificity of 76% to predict an unsuccessful outcome based on receiver‐operating characteristics curve analysis (area under the curve =0.688, P= .079). Affected dogs with a CSF MBP concentration ≥3 ng/mL had 0.09 times the odds of ambulation at follow‐up compared with affected dogs with CSF MBP concentration <3 ng/mL when adjusted for initial MFS (95% confidence interval 0.01–0.66, P= .018). Conclusions and Clinical Importance: These results would suggest that CSF MBP concentration may be useful as an independent prognostic indicator in dogs with thoracolumbar IVDH.  相似文献   
999.
7 病原-宿主关系的改变以及宿主内的疾病过程 如上所述,改变宿主和疾病病原之间的关系可能会使病原自身发生变化,或者会引起宿主之间的疾病过程变化以及传染原在宿主间的传播变化。 通常来说,当宿主很少暴露给特定病原时,由于缺少先天性抵抗力(由遗传决定)和未经免疫的宿主,从而使最严重的疾病症状得以发生,易感年龄间变化最小。宿主先天性抵抗力可能受到一定程度的自然因素或人为的管理因素作用,尤其是在最严重或最麻烦的疾病方  相似文献   
1000.
Tuberculosis, associated with Mycobacterium bovis infection, occurs infrequently in sheep. A sheep flock, which was potentially exposed to a high level of infection from in-contact tuberculous cattle, was examined for evidence of infection. Six sheep that had given a positive reaction to the comparative intradermal tuberculin test were examined post mortem. Tuberculous lesions were present in four of these sheep. Lesion morphology and distribution in the sheep was similar to that in cattle. M. bovis was cultured from the lesions and the isolates were strain typed by spoligotyping and variable number of tandem repeats (VNTR) typing. Tuberculin-reacting sheep also reacted positively to an assay for in vitro release of interferon-gamma. This paper describes the first report of an outbreak of tuberculosis in sheep in either Britain or Ireland. The report describes immunology and pathology findings and, using molecular typing techniques, suggests that the sheep had been infected from in-contact cattle.  相似文献   
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