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排序方式: 共有1002条查询结果,搜索用时 15 毫秒
51.
Abstract The efficacy of twice daily topical application of capsaicin (0.025%) for the management of pruritus in dogs with atopic dermatitis (AD) was evaluated in double-blinded, placebo-controlled study. Twelve dogs with AD were randomly assigned to either 0.025% capsaicin or vehicle lotion applied twice daily for 6 weeks. After a 4-week wash-out period, treatments were switched. Significant improvement was reported by owners ( P  = 0.0006), but not by investigators. Owners noted temporary worsening of pruritus after the first week of capsaicin therapy. Overall capsaicin was well tolerated. Substance P (SP) concentrations in the skin did not correlate with the severity of the pruritus and did not change significantly over time and between treatments. Lesional skin had less SP than nonlesional skin ( P  = 0.03). These observations suggest that topical capsaicin should be further evaluated as an adjunctive antipruritic agent in dogs with AD.  相似文献   
52.
A total of 162 sheep fleece samples were collected from 2315 sheep clinically examined for evidence of dermatitis. The sheep belonged to 32 flocks raised in northern and middle Jordan. Eighty-three samples showed no obvious abnormalities, whereas the remainder showed exudation (79 samples), fleece discoloration (18) and fleece roughness (40) and abscesses (7). Seventeen Pseudomonas aeruginosa isolates were obtained from these samples. Antibacterial resistance in vitro was common; resistance to tetracycline, amoxycillin, erythromycin and cotrimoxazole was shown by > 90% of the isolates. Resistance to norfloxacin (29.4% of isolates), ciprofloxacin (17.6%) and amikacin (17.6%) was also demonstrated. Fourteen isolates were serum resistant when assessed after 1-3 h incubation in sheep and calf sera, and their count increased by 2-2.9 and 2.5-3.5 respectively.  相似文献   
53.
Erythema ab igne, an old and rare disease in the human literature, is an erythematous, often pigmented, reticular, macular dermatosis that occurs at the site of repeated exposure to moderate heat. We identified lesions consistent with erythema ab igne in five dogs, three cats and one silvered langur (Trachypithecus cristatus[Raffles, 1821]). In dogs and cats, the cutaneous lesion distribution typically reflected chronic exposure to moderate heat during lateral or sternal recumbency. The silvered langur developed cutaneous lesions on the dorsal neck from exposure to a heat lamp. Principal clinical lesions consisted of irregular areas of alopecia (7/9) and erythema (7/9), sometimes with hyperpigmentation (3/9). Principal histological features consisted of karyomegaly (9/9) and keratinocyte atypia (4/9), scattered apoptotic or vacuolated basal cells and/or apoptotic keratinocytes (6/9), mild mixed mononuclear interstitial or interface dermatitis (9/9) with adnexal atrophy (8/9), and a variable number of wavy eosinophilic elastic fibres (9/9). The presence of these cutaneous lesions in an animal indicates that the environment should be evaluated for exposure to chronic moderate heat, and the heat source should be eliminated or modified to prevent further exposure and progression of lesions.  相似文献   
54.
One hundred and sixty-nine dogs were diagnosed with atopic dermatitis, and treated with hyposensitization for at least 1 year based on the results of either intradermal skin tests (IDST) or enzyme-linked immunosorbant serum assays (ELISA). Excellent (i.e. hyposensitization alone controlled clinical signs), good (> 50% improvement), moderate (< 50% improvement) and no (clinical signs were unchanged) responses were seen in 19.5, 32.5, 20.1 and 27.8%, respectively. Age of onset, age when treatment was initiated or the duration of clinical signs had no influence on response to hyposensitization. Dogs having concurrent flea allergy dermatitis were statistically more likely to respond better than dogs with concurrent food allergies. Although not statistically significant, there were trends for Golden Retriever and male dogs to respond better than other breeds and female dogs, respectively. Dogs having more than 21 positive reactions in allergy tests and treated with more than 21 allergens had lower response scores, and a longer time course before achieving beneficial response. Lower response scores were seen in dogs having positive reactions to cultivated plants, grasses, trees or insects. There was no difference in response to hyposensitization whether based on IDST or ELISA results.  相似文献   
55.
Abstract We have previously shown that both atopic and normal dogs generate an IgG response to antigens of Malassezia pachydermatis . The aim of this study was to compare IgE responses to separated proteins of M. pachydermatis in 28 atopic dogs with Malassezia dermatitis and 22 clinically normal dogs using Western immunoblotting. Six different detection systems were evaluated in order to assess sensitivity and eliminate nonspecific binding and cross-reactivity. The protocol yielding the best results utilized a monoclonal mouse antidog IgE, an alkaline phosphatase conjugated goat antimouse IgG which had been passed through a canine IgG column 3 times, a chemiluminescent substrate and a digital imaging system. Proteins of 45, 52, 56 and 63 kDa were recognized by more than 50% of the atopic dog sera and thus represented major allergens. Only a minority of normal dogs showed faint IgE binding to these proteins. The results indicate that the majority of atopic dogs with Malassezia dermatitis have a greater IgE response than normal dogs, suggesting an IgE-mediated immune response may be clinically important in the pathogenesis of the disease.  相似文献   
56.
A model was developed to explain the influence of different local and regional factors on the prevalence of foot-pad dermatitis in broilers at the time of slaughter. Data from a recent two-year study of broiler foot-health in Sweden were used to construct the model. The model was based on regression analysis, using a Tobit model for censored data. This type of Tobit regression model has been used for several decades in econometrics and can also be found in the medical-scientific literature. It has, however, reportedly not been used in veterinary medicine although there appears to be several situations where it should be considered useful. Week of slaughter was significantly (p<0.001) associated with total foot-pad score, which decreased over time. The birds' age at slaughter was also significantly (p<0.01) associated with total foot-pad score. Five out of the 11 slaughterhouses included in the study were included as significant (p<0.01) variables in the final model. Three feed suppliers (p<0.05) and four regions (p<0.01) were also included as significant variables in the model. There were also significant (p<0.001) interactions between several of these factors (mainly, between the time variable and specific slaughterhouses, feed suppliers or regions, respectively).

The information gathered in this study regarding the influence of a number of risk factors for the development of foot-pad dermatitis and their reciprocal interactions will enable us to modify the Swedish broiler foot-health programme.  相似文献   

57.
平缓地带数字土壤制图中,环境协变量的选择是提高制图精度的关键。已有研究证明遥感影像可作为推理制图的辅助因子,而如何确定环境因子推理制图时各自的权重已成为现阶段研究的重点。选取湖北省麻城市乘马岗镇为研究区,采用3种特征筛选方法进行有效环境变量筛选,探索参与平原-丘陵混合区域制图的因子并确定其重要性,依据选择的相对稳定的指标,进一步探索提高土壤类型制图准确性的途径。根据141个野外独立样点的检验结果表明:在推理制图中,遥感因子在平原区域的重要性程度高于丘陵区域,且遥感因子中归一化植被指数(NDVI)和均值(Mean)较为稳定;基于递归特征算法的按地形推理制图精度最高为75.89%,分别高于ReliefF算法和基于Tree的特征筛选算法13.48%和4.97%;此外3种特征筛选算法制图结果中,按地形因子分区制图的精度均高于整体区域制图。因此,遥感因子作为辅助手段参与推理过程可有效提高制图精度。本研究采用的特征挖掘与机器学习算法对提升土壤制图精度具有一定的理论意义。  相似文献   
58.
Abstract This study describes 26 cats with mosquito bite hypersensitivity. Most were short-haired, free-roaming cats. Typical clinical features were seasonal (summer), symmetric miliary dermatitis on the pinnae. Mosquito bite exposure with Aedes albopictus was performed on the pinnae and the lateral thorax in five cases and three healthy cats. All sites showed weals within 20 min. Papules, which revealed eosinophilic dermatitis, were recognized during a 12–48-h period. The control cats showed only slight and transient erythema after being bitten. Intradermal skin tests with an extract of A. albopictus were performed in three cases, and Prausnitz-Küstner tests under A. albopictus bites were performed in three cases. Both tests showed weals in all cases studied, although papules were not observed. Intradermal skin tests with the control cats, and Prausnitz-Küstner tests with saline and healthy cat serum failed to produce any positive reactions. The findings indicate that mosquito bite hypersensitivity in cats is triggered by a type I hypersensitivity reaction to mosquito antigens. Certain other factors may be involved in the formation of delayed papular reactions. Whether this is a normal or abnormal reaction to mosquito bites is also discussed. Résumé— Cette étude a été réalisée sur 26 chats atteints d'hypersensibilité aux piqûres de moustiques. La plupart des chats sont des chats à poils courts vivant à l'extérieur. Les lésions cliniques sont caractérisées par une dermatite miliaire symétrique sur les pavilions auriculaires survenant l'été. Une exposition aux piqûres de moustique (Aedes albopictus) a été réalisée sur les pavilions auriculaires et sur la face latérale du thorax de 5 chats atteints et de 3 chats sains. Tous les sites d'exposition montrent des reactions à 20 minutes. Ces papules qui traduisent une dermite éosinophilique, persistent pendant 12 à 48 heures. Les chats sains ne montrent qu'un érythème transitoire après la piqûre, des tests d'intradermoréaction avec un extrait d'A. albopictus ont été réalisés dans 3 cas, des tests de Prausnitz-Küstner spécifiques dans 3 cas. Les deux tests montrent des reactions dans tous les cas étudiés bien que des papules ne soient pas observées. Ces tests réalisés sur les chats témoins, ne montrent aucune reaction, positive ou significative. Ces résultats suggèrent que l'hypersensibilité aux piqûres de moustiques chez le chat est regie par une hypersensibilité de type I à divers antigènes de moustique. D'autres facteurs doivent intervenir dans la formation des reactions papuleuses retardées. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Réactivité cutanée aux piqûres de moustiques et à leurs antigènes chez le chat.) Veterinary Dermatology 1997; 8 : 19–26.] Résumén Este estudio describe 26 gatos con hipersensibilidad a la picadura de mosquito. La mayoria eran gatos en régimen abierto de pelo corto. Las caracteristicas clinicas tipicas fueron dermatitis miliar simétrica estacional (verano) en pabellones auriculares. Se llevó a cabo una exposición a la picadura del mosquito Aedes albopictus en los pabellones y en el tórax lateral en 5 casos y 3 gatos sanos. Todas las zonas mostraron ronchas a los 20 minutos. Aparecieron pápulas con dermatitis eosinofilica a las 12 a 48 horas. Los gatos control mostraron solamente eritema leve y transitorio tras la picadura. Se realizaron pruebas cutáneas intradérmicas con extracto de A. albopictus en 3 casos y pruebas de Prausnitz-Küstner bajo picaduras de A. albopictus en 3 casos. Ambas pruebas mostraron ronchas en todos los casos estudíados, aunque no se observaron pápulas. Las pruebas intracutáneas con los gatos control y las pruebas de Prausnitz-Küstner con suero salino y suero de gatos sanos no causaron reacción positiva. Estos hallazgos indican que la hipersensibilidad a la picadura de mosquito se inicia por una hipersensibilidad de tipo I a antigenos del mosquito. Otros factores pueden estar implicados en la formación de reacciones papulares retardadas. Se discute si esta es una reacción normal o anormal a la picadura de mosquito. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Reactividad cutanea a las picaduras de mosquito y sus antigenos en el gato.) Veterinary Dermatology 1997; 8 : 19–26.] Zusammenfassung— Diese Studie beschreibt 26 Katzen mit Mückenstichhypersensibilität. Die meisten der Tiere waren kurzhaarig und hatten Freilauf. Die typischen klinischen Bilder bestanden in säsonaler (Sommer), symmetrischer miliarer Dermatitis an den Ohrmuschein. Es wurde eine Exposition auf Mückenstiche mit Aedes albopictus an den Ohrmischein und am lateralen Thorax bei 5 Patienten und 3 gesunden Katzen durchgeführt. Alle Stellen zeigten Quaddeln innerhalb von 20 Minuten. Papeln, die eine eosinophile Dermatitis enthüllten, wurden nach einer Zeitspanne von 12 bis 48 Stunden gesehen. Die Kontrollkatzen zeigten ein nur leichtes und transientes Erythem nach dem Biß. Intradermale Hauttests mit einem Extrakt von A. albopictus wurden in 3 Fallen durchgeführt und Prausnitz-Küstner-Tests unter A. albopictus-Bissen wurden in 3 Fallen durchgeführt. Beide Tests zeigten Quaddeln in alien untersuchten Fallen, obwohl Papeln nicht beobachtet wurden. In den intradermalen Hauttests bei den Kontrollkatzen und Prausnitz-Küstner-Tests mit Kochsalz-Lösung und Serum gesunder Katzen gelang es nicht, irgendweiche positiven Reaktionen zu erzeugen. Diese Befunde zeigen, daß Mückenstichhypersensibilität bei Katzen durch eine Typ 1-Hypersensibilitätsreaktion auf Mückenantigene ausgelöst wird. Bestimmte andere Faktoren können in die Bildung von verzögerten papulären Reaktionen miteinbezogen sein. Ob dies eine normale oder unnormale Reaktion auf Mückenstiche ist, wird ebenfalls diskutiert. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Hautreaktivität auf Mückenstiche und Antigene bei der Katze.) Veterinary Dermatology 1997; 8 : 19–26.]  相似文献   
59.
A retrospective histopathological and immunopathological study was conducted on 86 dogs with Malassezia dermatitis. West Highland White terriers, English Setters, Shih Tzus, Basset Hounds, American Cocker Spaniels, spayed females, and castrated males were found to be at increased risk. The histopathological reaction pattern of lymphocytic superficial perivascular to interstitial dermatitis with parakeratotic hyperkeratosis, irregular epidermal hyperplasia, diffuse intercellular oedema and lymphocytic exocytosis was found to be consistent with a diagnosis of Malassezia dermatitis whether yeast were histologically visible (73.3% of the cases) or not (26.7%). Immunopathological studies revealed that 60– > 90% of the inflammatory cells within the epidermis, and 25–75% of those within the dermis were CD3+T lymphocytes, and that the only immunoglobulin-positive cells were dermal plasma cells.  相似文献   
60.
文章通过对目前图书馆在资源建设中存在的主要问题进行了分析,并对资源整合的现有模式、存在的难点以及对资源整合研究中的问题,应采取推进的措施进行了论述。  相似文献   
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