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321.
 山西晉中一带麦田边生有大量碱草(Elymus chinense),严重感染条锈病。接种試驗証明小麦条銹菌与碱草条銹菌在致病力方面有显著差异。碱草对14个小麦条銹菌种均抵抗,碱草条銹菌虽能侵染小麦,但13个小麦推广品种对所有5个碱草菌种都表現抵抗。田間調查結果亦示明碱草条銹菌虽能侵染小麦,但麦叶仅产生抗性的枯斑及形成极少量的夏孢子堆,并証实其不能在小麦上继續繁殖。不同小麦的种对碱草条锈菌亦均免疫或高度抵抗。小麦条銹菌能侵染冰草(Agropyron cristatum)等11种禾草,其中旱雀麦(Bromus tectorum)及西伯利亚碱草,(Elymus sibiricus)高度感染。碱草条銹菌較小麦条銹菌能适应更高的气温,在25℃仍能正常侵染碱草且产生大量孢子堆,其夏孢子(28.94μ×22.41μ)亦显著較小麦条銹菌的夏孢子(26.10 μ×19.48μ)为大,因此是条銹菌(Puccinia glumarum)的一个較为特殊的生理小种(YIE)。西伯利亚碱草(Elymus sibiricus)、山大麦及麦穗草(Agropyron spp.)的条銹菌均能正常侵染小麦,但尚未发現其大量感染条銹病的羣落。  相似文献   
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The clinical, electrocardiographic, angiographic, radiological and postmortem features of a case of pseudo truncus arteriosus in an 8-month-old crossbred Labrador puppy are described.  相似文献   
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 洋麻炭疽病目前是我国麻区限制洋麻生产的主耍因素[1,2,5]。病原菌经鉴定是(Colletotrichunm hibisci Pollacci)。  相似文献   
326.
Systemic lupus erythematosus (SLE) was diagnosed in a 9-year-old castrated male Persian cat. The cat described is the first to fulfil four of 11 American Rheumatism Association criteria for the diagnosis of SLE in humans (symmetrical facial dermatitis, thrombocytopenia, positive antinuclear antibodies, oral ulceration) with supportive skin histopathology. Haematological abnormalities included a mild anaemia and severe thrombocytopenia. Skin disease consisted of symmetrical multifocal alopecia with crusting, predominantly on the face. Histopathology of the skin revealed interface dermatitis and interface folliculitis with follicular atrophy. Complete remission was obtained with corticosteroid therapy.  相似文献   
327.
Abstract. Collagenase was used to prepare primary cell cultures from rainbow trout, Oncorhynchus mykiss (Walbaum), gills. Although difficult to subcultivate, one primary culture led to the development of a cell line, RTgill-W1. RTgill-W1 grew in the basal medium, L-15, supplemented with foetal bovine serum at between 5 and 10%, but not in L-15 alone. The cells have been passaged approximately 50 times over a 4-year period. At confluency, the cell shape was predominantly polygonal or epithelial-like. RTgill-Wl cultures were demonstrated by DNA staining with H33258 and by growth on agar to be contaminated with mycoplasma, but this contaminant was eradicated by treatment with mycoplasma removal agent (MRA) and BM cyclin.  相似文献   
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Superficial tumors are not routinely evaluated by two- or three-dimensional diagnostic imaging methods as part of the staging of canine cancer patients, although superficial tumors are readily imaged by ultrasound. The objectives of this study were to characterize the ultrasonographic patterns of superficial tumors and to evaluate whether ultrasound can help discriminate between benign and malignant tumors in dogs. Superficial tumors (n=132) in 86 dogs were evaluated by B mode, color flow mapping, and spectral Doppler ultrasonography. Size, echogenicity, tumor border definition, invasiveness, acoustic transmission, presence and distribution of vascular flow to and within the tumor, as well as perfusion indices were measured. The tumors were classified as lipomas, benign tumors, atypical mammary tumors, and malignant tumors. Multivariate statistics using discriminant analysis was used to determine which parameters may be used to predict the status of the tumor. Tumor echogenicity, border shape, acoustic shadowing, total number of vessels to the tumor and the total flow amount are the parameters that in combination resulted in the lowest classification error (24%), meaning that on average three out of four tumors were correctly classified using these parameters. All the lipomas and atypical mammary tumors were classified correctly by ultrasonography. The results of this study show that ultrasonography has an important role in the evaluation of canine superficial tumors, particularly in the evaluation of tissue homogeneity and tumor vascularity.  相似文献   
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