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81.
Amyloidosis is a disease characterized by the tissue deposition of autologous extracellular fibrillar proteins that can result in compression of adjacent tissues. Amyloidosis is well-recognized in a wide variety of animals, including mammals, birds, and reptiles. However, to date, there is only one report of amyloidosis in cetaceans. During 1999 and 2000, among 12 Stejneger's beaked whales (Mesoplodon stejnegeri) that were stranded along the Sea of Japan's coast, amyloidosis was found in two whales (case 1, 498 cm, male; case 2, 520 cm, female). For this study population, the prevalence rate of amyloidosis was approximately 17%. These two animals were considered physically and sexually mature based on body length, external features, gonad characteristics, and skeletal features. Livers were notably swollen, fragile, and pale (brownish yellow) on gross examination. A large deposit of amyloid was found in Disse's spaces along with marked atrophy of the hepatocytes. Numerous granulomas, including many nematodes (Crassicauda sp.), were found along with amyloid deposition in the kidneys. Amyloid was also detected in the heart, spleen, adrenal gland, and pancreas. Amyloid in both cases was identified by typical morphology on H&E and Congo red staining. Electron microscopy displayed a typical network of fine fibrils measuring about 11 nm in diameter. This is the first report of amyloidosis in two Stejneger's beaked whales stranded on the coast of the Sea of Japan.  相似文献   
82.
This study describes observations related to 93 cases of strychnine poisoning in dogs over a 16-year period in Saskatchewan, Alberta, and Manitoba. Epidemiological information describing age, gender, breed, and size of the dogs, geographical distribution of poisonings, and strychnine concentrations in tissue matrices were tabulated. The mortality in dogs poisoned with strychnine was 60.2%. Strychnine poisoning cases varied by year (P = 0.0012) and by season (P = 0.0005). The highest number of confirmed cases occurred in years 2000 and 2001. Poisonings occurred most frequently during the spring. There were no statistical differences related to age or gender, but older, male dogs appeared to be more commonly affected. Large dog breeds were most commonly affected. Strychnine was detected in multiple tissue matrices, including stomach contents, liver, urine, vomitus, and gastric washings. The study indicates that strychnine poisoning in the dog remains a common toxicosis in western Canada.  相似文献   
83.
84.
The presentation, treatment and outcomes of 33 ingluvial fibrous foreign bodies in cockatiels (Nymphicus hollandicus) are described. Vomiting, lethargy and weight loss were the most common presenting signs. Diagnosis was made on palpation of a mass in the crop (ingluvies). Both surgical and non‐surgical treatment regimens were evaluated. The overall mortality rate was 33%, suggesting fibrous materials are not safe for cockatiels to groom or ingest and should not be offered as cage accessories.  相似文献   
85.
A biometrical study of female porcine reproductive tracts recovered after slaughter was carried out. Sizes and weights of the various areas from one hundred eighty-seven sow tracts, eighty-one pre-puberal gilts and thirty-two puberal gilts were recorded. A table of abnormalities observed in examination of the sow tracts is also presented.  相似文献   
86.
Extract

As part of a larger project investigating methods of brushtail possum (Trichosurus vulpecula) biocontrol, possum sera were collected from 15 sites throughout New Zealand and its offshore islands. These sites were selected to cover the original release sites of possums in New Zealand.  相似文献   
87.
The primary structure and heterogeneity of tau protein from mouse brain   总被引:74,自引:0,他引:74  
Tau protein is a family of microtubule binding proteins, heterogeneous in molecular weight, that are induced during neurite outgrowth and are found prominently in neurofibrillary tangles in Alzheimer's disease. The predicted amino acid sequences of two forms of tau protein from mouse brain were determined from complementary DNA clones. These forms are identical in their amino-terminal sequences but differ in their carboxyl-terminal domains. Both proteins contain repeated sequences that may be tubulin binding sites. The sequence suggests that tau is an elongated molecule with no extensive alpha-helical or beta-sheet domains. These complementary DNAs should enable the study of various functional domains of tau and the study of tau expression in normal and pathological states.  相似文献   
88.
A mathematical model is used to investigate the impact of farming intensity and water management on nitrogen dynamics in the water column of intensive aquaculture ponds. The model describes the input of ammonia, its assimilation by phytoplankton or nitrification, and the loss of nitrogen through sedimentation, volatilization, and discharge. The model is calibrated for two commercial shrimp (Penaeus monodon Fabricius) farms in Thailand. Assimilation by phytoplankton with subsequent sedimentation or discharge is the principal process of ammonia removal. When inputs of ammonia exceed the algal assimilation capacity (carrying capacity), nitrification and volatilization of excess ammonia become significant. Carrying capacity is negatively affected by non-chlorophyll turbidity, and was estimated as 6 t ha?1 cycle?1 at a non-chlorophyll extinction of 2.6 m?1. In ponds managed within their carrying capacity, ammonia concentrations are lowest at no water exchange, reach a maximum at exchange rates between 0.2 and 0.4 day?1, and decline again at higher rates. When the carrying capacity is exceeded, excess ammonia concentrations decline continuously with increasing water exchange. Average exchange rates used in intensive shrimp farms (up to 0.2 day?1) reduce phytoplankton abundance and sedimentation within ponds, but not ammonia concentrations. Discharges are high in particulate nitrogen at water exchange rates up to 0.3 day?1, but contain mainly dissolved nitrogen at higher rates.  相似文献   
89.
Uninfected plants of spring wheat ‘Kolibri’ and plants infected with leaf rust were grown in a climate chamber at three soil-water potentials: ?1025 J.kg?1 (D, ‘dry’, near wilting point), ?425 J.kg?1 (M, ‘medium’, intermediate), and ?250 J. kg?1 (W, ‘wet’, near saturation point). At lower water potentials plant development was faster, growth rate lower, and transpiration less than at higher water potentials. Growth and transpiration of plants at W were approximately twice those at D. Plants at M showed an intermediate response. Growth and yield of rusted plants grown at M were only slightly less than those of the uninfected controls, whereas at D and W considerable losses of plant dry weight and yield were caused by the rust. Infection type, pustule size and spore production were related to soil-water potential; at M, the pustules were smallest and the spore production was minimal. Results show a marked effect of soil-water potential on plant morphogenesis, and indicate that resistance of ‘Kolibri’ to leaf rust was related to soil-water potential. Optimal resistance was found at M, the intermediate soil-water potential.  相似文献   
90.
Osteosarcoma of the axial skeleton in an 18-month-old woma python (Aspidites ramsayi) is described. A subcutaneous mass overlying the costal arches enlarged progressively over a period of 5 months and, in that time, became ulcerated and more invasive of surrounding tissues. A punch biopsy of the lesion under general anaesthesia provided tissue for histopathology and diagnosis of low-grade osteosarcoma.  相似文献   
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