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61.
Avena magna is a new tetraploid species morphologically similar to the hexaploid A. sterilis, having a high concentration of protein, large caryopses, and outstanding resistance to crown rust. One genome in A. magna appears homologous to the As genome present in hexaploid, tetraploid, and one group of diploid species. Avena magna is a possible ancestor of cultivated oats.  相似文献   
62.
Vertebrate pest control in California is often accomplished through the use of rodenticide grain baits. These grain baits are composed of steam-rolled oats (SRO), a toxicant, an indicator dye and an oil combination. A series of tests were performed to determine the effects of various dye and oil formulations on acceptance of grain bait by Norway rats [Rattus norvegicus (Berk)], California ground squirrels [Spermophilus beecheyi (Richardson)] and pocket gophers (Thomomys bottae Eyd & Gerv). Seven different dyes, four oil formulations and clean (untreated) oats were tested for acceptance. The addition of the selected oils and dyes to grain resulted in no significant differences in consumption. This indicates that there is a wide variety of dyes that could be used in the formulation of rodenticides. These alternatives could aid in proper pesticide use, the deterrence of bait consumption by birds and possibly in ingredient adhesion to the finished bait.  相似文献   
63.
Twenty-three leopard geckos (Eublepharis macularius) with various clinical histories of weight loss, anorexia, lethargy, and diarrhea were submitted either intact or as biopsy specimens to the University of Florida Anatomic Pathology Service. Gross necropsy findings in the intact geckos included marked reduction of subcutaneous adipose tissue stores at the tail base and mild thickening and reddening of the small intestine. Histologic examination revealed Cryptosporidium sp. infection associated with hyperplasia and mononuclear inflammation of the small intestine in all geckos. Parasites and lesions were only rarely observed in the stomach and large intestine of geckos. The histologic and ultrastructural lesions in the small intestine of leopard geckos infected with Cryptosporidium sp. have not been well characterized previously. This report implicates Cryptosporidium sp. as the cause of disease in the geckos and describes the range of histologic lesions observed.  相似文献   
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65.
Five painted storks were treated with fenbendazole for 5 days for internal parasitism. Four birds died following treatment. Profound heteropenia was a consistent finding in all samples evaluated; additionally, the 1 surviving bird had progressive anemia. Consistent necropsy findings in the 4 birds that died were small intestinal crypt cell necrosis and severe bone marrow depletion and necrosis. Fenbendazole has been associated with bone marrow hypoplasia and enteric damage in mammals and other species of birds. The dosages of fenbendazole used in birds are often substantially higher than those recommended for mammals, which may contribute to bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in birds.  相似文献   
66.
Possible intraspinal metastasis of a canine spinal cord nephroblastoma   总被引:1,自引:0,他引:1  
A 2-year-old Basset Hound was admitted to the University of Florida Veterinary Medical Teaching Hospital with progressive spastic paraparesis. At necropsy, intradural extramedullary tumors produced areas of spinal cord swelling and softening in spinal cord segments T11-T12 and L4-L6. Histologic examination of the masses revealed sheets of polygonal blastemal cells, epithelial cells forming tubules and rosettes, and embryonal glomeruloid-like structures in the thoracic mass. Cells in the lumbar mass were less differentiated, forming rare tubules and no glomeruloid-like structures. The occurrence of two tumors in the spinal cord along with the less differentiated appearance of the lumbar tumor raises the possibility that the lumbar mass arose as a result of intraspinal metastasis. To our knowledge, this is the first report of multifocal or metastatic canine spinal nephroblastoma. In addition, the vimentin and cytokeratin immunohistochemical staining characteristics of these spinal cord nephroblastomas are described.  相似文献   
67.
Idiopathic hypoparathyroidism in a 3-year-old dog was manifested clinically as periodic episodes of depression, vomiting, and tetanic convulsions. Hypocalcemia and hyperphosphatemia were detected late in the course of the illness, but the dog died before corrective measures could be instituted. The pathologic features were similar to those reported in dogs in which hypoparathyroidism was induced by injection of homologous parathyroid tissue, thus suggesting an auto-immune pathogenesis.  相似文献   
68.
Ontogeny of the immune system   总被引:2,自引:0,他引:2  
Cellular and humoral aspects of the immune response develop sequentially in the fetus. Although there is evidence of immunologic activity to some antigens, many of the nonimmune effector systems are neither developed nor fully functional in the fetus. The lack of fully functional systems make the fetus a highly susceptible candidate for invading bacteria and viruses. Often, infection prior to immune competence may lead to abortion, malformation, and in some instances, viral persistence and immune tolerance. On the other hand, immune responses tend to elevate immunoglobulin values and cause specific antibody that may be used for diagnostic purposes. Little work has been done to appreciate fully the immunologic and nonimmune effector systems' role in normal development or during congenital infections.  相似文献   
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