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1.
Magnetic resonance imaging (MR) was used to make a diagnosis of equine nigropallidal encephalomalacia in a horse. Equine nigropallidal encephalomalacia is a neurodegenerative disease that has many characteristics with Parkinson-like diseases in humans. Historically, horses were euthanized based on clinical signs and exposure to the toxic weed, yellow star thistle (Centaurea solstitialis). Previously, the disease has only been confirmed on necropsy. MR imaging can provide accurate and sensitive visualization of typical lesions seen in the brain of horses affected with equine nigropallidal encephalomalacia. Lesions were seen on T1-weighted, T2-weighted and proton density images. There was no contrast enhancement following Gd-DTPA administration. Lesions seen on MR were confirmed at necropsy. Using MR to confirm a diagnosis of equine nigropallidal encephalomalacia will prevent unnecessary suffering of horses and expense to owners that would otherwise incur, while further diagnostics are performed.  相似文献   
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Coccidioidomycosis was diagnosed in 48 cats. Forty-one cases were identified within a period of 3 years. Coccidioides immitis was revealed by cytological or histopathological examinations, or culture in 70% of cats. The remaining 30% of cases were diagnosed by appropriate clinical signs, radiographic lesions, and serological test results. The average age of affected cats was 6.2 years with a median age of 5.0 years. Fifty-four percent (n = 26) were female and 46% (n = 22) were male. Domestic shorthaired and longhaired breeds comprised 89% (n = 41) of affected cats. Sixty-seven percent of cases were diagnosed during the 6-month period of December through May. Cats infected with C immitis were presented for evaluation of dermatologic (56%), respiratory (25%), musculoskeletal (19%), and neurological or ophthalmologic signs (19%). Fever, inappetence, and weight loss were present in 44% of the cats. Duration of clinical signs before diagnosis was less than 4 weeks in 85% (n = 42) of cats, with an average of 3.8 weeks and a median of 2 weeks. Agar gel immunodiffusion tests were positive in all 39 cats tested at sometime during the course of their disease. Hyperproteinemia (greater than 7.9 g/dL) was present in 52% (10/23) of cases. The majority of cats (n = 39) were negative for feline leukemia virus. Antibodies to feline immunodeficiency virus were absent in the 19 cats tested. Ketoconazole was the most common antifungal agent used to treat cats with Coccidioidomycosis. Duration of treatment ranged from less than 1 week to 43 months. Thirty-two cats are currently asymptomatic, with or without treatment. Eleven cats died or were euthanized. Five cats were lost to follow-up. Ketoconazole likely is more suppressive than curative because relapses were common after discontinuing therapy.  相似文献   
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Cystic lymphangiomas are rare malformations of the lymphatics that result in the formation of a cystic mass. Where multiple cysts are seen, the condition is termed cystic lymphangiomatosis. This case describes the diagnosis and unique management of cystic lymphangiomatosis in a 10‐day‐old Thoroughbred foal. Ultrasonography, histopathology and laparoscopy were essential for diagnosis and appreciation of the extent of disease. Ultimately, the cystic lymphangiomatosis was so extensive in this foal that complete surgical excision was considered impossible and the presence of adhesions within the abdomen indicated a very poor long‐term prognosis; the owners elected for euthanasia at age 14 weeks. Although rare, lymphangioma and lymphangiomatosis should be considered as a differential diagnosis for an intra‐abdominal mass in a young horse.  相似文献   
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氯的使用可有效减少家禽胴体和屠宰加工厂的细菌。但是,我们有必要对氯有一个更好的认识和管理。  相似文献   
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A multiplex PCR-ELISA protocol for detection ofClavibacter michiganensis subsp.sepedonicus (Cms) was developed that is based on primers for amplification of three single-copy, unique DNA sequences, Cms50, Cms72, and Cms85. The three sequences were simultaneously amplified from the genomes of all 42 strains of Cms that were tested including variant mucoid forms, but not from strains representing five related subspecies, andRathayibacter rathayi andRhodococcus faciens. The lowest limit of detection by gel electrophoresis was estimated to be approximately 300 CFU per mL when cells were spiked into potato core fluid, but sensitivity increases approximately 10-fold using PCR-ELISA. Inclusion of a sea anemone DNA fragment engineered so it could be amplified from the Cms72 primer set provided the simultaneous signal that the system functioned properly when any sample was free of the pathogen. The addition of hydrolyzed casein to the reaction mix was demonstrated to markedly reduce or eliminate inhibition of PCR by plant cell components or contaminants. Multiplex PCR-ELISA detection of Cms was determined to be verifiable for analysis of both stems and tubers based on the amplification of multiple sites in its genome, it provides absolute specificity, and it was more sensitive than detection based on gel electrophoresis of PCR products and serological approaches.  相似文献   
9.
Diamonds with delta(13)C values of -2 per mil and less than 50 parts per million (by mass) nitrogen have been isolated from the Abee enstatite chondrite by the same procedure used for concentrating Cdelta, the putative interstellar diamond found ubiquitously in primitive meteorites and characterized by delta(13)C values of -32 to -38 per mil, nitrogen concentrations of 2,000 to 12,500 parts per million, and delta(15)N values of -340 per mil. Because the Abee diamonds have typical solar system isotopic compositions for carbon, nitrogen, and xenon, they are presumably nebular in origin rather than presolar. Their discovery in an unshocked meteorite eliminates the possibility of origins normally invoked to account for diamonds in ureilites and iron meteorites and suggests a low-pressure synthesis. The diamond crystals are approximately 100 nanometers in size, are of an unusual lath shape, and represent approximately 100 parts per million of Abee by mass.  相似文献   
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Compensatory growth (CG) or “catch‐up growth” is a period of super‐accelerated growth following a period of suboptimal conditions (i.e., lack of prey availability or overwintering). Little is known about the CG response in pond‐raised fish and whether hybrid striped bass (HSB), Morone chrysops × Morone saxatilis, might exhibit the rapid growth states or improvements in other production characteristics that may accompany the response. To evaluate the potential for CG in HSB culture, a 16‐wk growth trial in twelve 0.1‐ha earthen ponds was conducted. Approximately 2850 fish (mean weight ± SD = 3.2 g ± 1.1) were stocked into ponds and subjected to one of four cyclic feeding regimens. Treatment regimens included a control (0 wk, fed twice daily to apparent satiation) and cycles of 1, 2, or 4 wk of feed deprivation, followed by 1, 2, or 4 wk of feeding to apparent satiation. Fish in the 4‐wk feeding regimen were offered feed twice during the feed‐deprivation period (once every other week). Growth, specific growth rate (SGR), hepatosomatic index (HSI), intraperitoneal fat ratio, and condition factor (CF) were measured every other week, while overall growth, feed efficiency (FE) (FE = [weight gain/feed fed] × 100), and survival were calculated at the trial termination. The effect of these feeding regimens on water quality was examined by monitoring pH, turbidity, total ammonia nitrogen, nitrite–nitrogen, nitrate–nitrogen, soluble reactive phosphorus, and chlorophyll a weekly; total nitrogen and phosphorous biweekly; and dissolved oxygen and temperature twice daily. Cyclic feeding elicited CG; fish subjected to the 2‐wk regimen had a significantly higher SGR than 0‐wk controls during all but the final refeeding period. FE was higher for all fish in the cyclic regimens, although only FE for fish in the 2‐wk regimen was statistically greater (40%) than the controls. HSI was the most responsive measure and significantly decreased in the 2‐ and 4‐wk treatments during feed‐deprivation period and overcompensated during the refeeding period. CF also varied with feeding cycle and proved to be an effective nonlethal measure of predicting a CG response. No statistical differences in water quality parameters were observed. These data suggest that CG can be effectively induced in pond‐raised HSB and that the increase in FE warrants further research for practical application. Future pond studies with fingerling HSB fish should be conducted with emphasis on feed‐deprivation periods of 2 wk and refeeding periods of at least twice that of the feed‐deprivation period.  相似文献   
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