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排序方式: 共有169条查询结果,搜索用时 15 毫秒
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K. A. Selting S. E. Lana G. K. Ogilvie A. Olmstead D. L. Mykles J. Bright K. L. Richardson J. A. Walton E. Monnet M. J. Fettman 《Veterinary and comparative oncology》2004,2(3):142-156
The cumulative cardiotoxicity that occurs as a result of doxorubicin chemotherapy is irreversible and can affect both quality and quantity of life for the cancer patient. Cardiac troponin I (cTnI) is a sensitive and specific marker of cardiomyocyte death. The purpose of this retrospective study was to evaluate serum concentrations of cTnI in dogs with lymphoma or osteosarcoma given doxorubicin chemotherapy, and with known cardiac outcome, based on a minimum assessment by physical examination and thoracic radiography. Serum samples were also available for cTnI measurement from seven healthy dogs given intracoronary doxorubicin. Serial serum samples obtained before, during and after doxorubicin chemotherapy showed increased cTnI concentrations in some clinical patients following chemotherapy (P = 0.0083 compared to baseline), but this did not correlate with clinical signs of cardiomyopathy. In dogs that subsequently developed cardiomyopathy however, serum cTnI concentrations were elevated before clinical signs became evident (confirmed with echocardiography). 相似文献
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Gregory B. Daniel DVM MS Kyle K. Kerstetter DVM Jill E. Sackman DVM PhD Janice M. Bright MS DVM Dorothy Schmidt BS 《Veterinary radiology & ultrasound》1998,39(5):459-469
Radionuclide ventriculography has been used in humans to evaluate valvular incompetency. The stroke volume ratio, derived from the radionuclide ventriculogram, is used to quantify the severity of mitral regurgitation (MR). Previous studies conducted in humans have shown that left to right stroke volume ratio increases as the severity of MR increases. In this study, we evaluated radionuclide ventriculography as a noninvasive method to detect MR in dogs with surgically created mitral insufficiency. Six male and three female adult, conditioned mongrel dogs were used. Scintigraphic studies were performed prior to and 4 weeks after surgically created MR. Because of the overlap of the left and right ventricles when viewed from a left lateral position, we combined data from a first-pass radionuclide angiocardiogram with the radionuclide ventriculogram to obtain a corrected stroke volume ratio. Blood flow transit parameters were also derived from the first-pass radionuclide angiocardiogram. Standard left ventricular functional indices were also measured from the radionuclide ventriculogram. On the left lateral view of the heart, 25 to 30% of the right ventricular volume overlaps the left ventricle. After correcting for the overlap, the stroke volume ratio of normal dogs was 1.17±0.178 (mean±SD), which increased to 2.06±0.41 (mean±SD) (p<.001) 4 weeks after creation of MR. The was no significant change in left ventricular ejection fraction or peak rate of ejection following MR. The transit times of blood through the left ventricle were measured from the first-pass radionuclide angiocardiogram and were expressed as half-time clearance, peak clearance rate, and time to peak clearance rate. The baseline half-time clearance was 2.07±0.71 s (mean±SD), which increased to 6.70±4.89 s (mean±SD) (p=.02) after creation of MR. The baseline peak clearance rate was 49.75±8.96 cts/s (mean±SD), which decreased to 23.12±6.84 cts/s (mean±SD) (p<.001) after creation of MR. Stroke volume ratios significantly increased following creation of MR. Blood flow transit through the left ventricle slowed following creation of MR. The variability of these parameters were small in the baseline studies, suggesting these techniques may be clinically useful to gauge the severity of MR in dogs. 相似文献
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Freeman RG Grabar KC Allison KJ Bright RM Davis JA Guthrie AP Hommer MB Jackson MA Smith PC Walter DG Natan MJ 《Science (New York, N.Y.)》1995,267(5204):1629-1632
The self-assembly of monodisperse gold and silver colloid particles into monolayers on polymer-coated substrates yields macroscopic surfaces that are highly active for surface-enhanced Raman scattering (SERS). Particles are bound to the substrate through multiple bonds between the colloidal metal and functional groups on the polymer such as cyanide (CN), amine (NH(2)), and thiol (SH). Surface evolution, which can be followed in real time by ultraviolet-visible spectroscopy and SERS, can be controlled to yield high reproducibility on both the nanometer and the centimeter scales. On conducting substrates, colloid monolayers are electrochemically addressable and behave like a collection of closely spaced microelectrodes. These favorable properties and the ease of monolayer construction suggest a widespread use for metal colloid-based substrates. 相似文献
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Evaluation of Heterotrophic Algae Meal as a Diet Ingredient for Channel Catfish,Ictalurus punctatus 下载免费PDF全文
Zachary A. Kupchinsky Shawn D. Coyle Leigh A. Bright James H. Tidwell 《Journal of the World Aquaculture Society》2015,46(4):445-452
Most microalgae evaluated in aquaculture diets have been produced autotrophically. In order to produce a cost‐efficient biomass at greater magnitudes for biofuel feedstock, heterotrophic production may be warranted. However, the chemical/nutritional attributes of these microalgae could differ from those grown autotrophically. An 8‐wk feeding trial was conducted to evaluate Chlorella spp. algae meal (AM) that had been cultured heterotrophically. The oil (lipid) was extracted to simulate biofuel production. Juvenile channel catfish, Ictalurus punctatus (5.7 ± 1.4 g; 8.9 ± 0.8 cm), were stocked at 10 fish/tank into fifteen 37.7‐L aquaria in a closed recirculating system and fed one of the five experimental diets to apparent satiation twice daily. Diets contained either 0 (control, CTL), 10, 20, or 40% AM and an additional diet containing 40% AM was supplemented with 2% lysine (40% AM+LYS). After 8 wk, there were no statistically significant differences in terms of survival, dressout percentages, whole‐body proximate composition, or fatty acid composition of the fillets among fish fed the diets containing varying levels of AM without added lysine. Feed consumption and weight gain for fish fed the 10, 40, and 40% AM+LYS diets were significantly greater than those fed the CTL diet. Feed conversion ratio was significantly lower for fish fed the 40% AM+LYS diet compared to those fed all other diets, which did not differ significantly from each other. These data indicate that channel catfish readily accept and can efficiently utilize heterotrophically produced AM at levels up to at least 40% of the total diet and that AM may enhance diet palatability. 相似文献
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Shawn D. Coyle Leigh Anne Bright David R. Wood Russell S. Neal James H. Tidwell 《Journal of the World Aquaculture Society》2011,42(5):687-695
The development of biofloc production technology has generated significant commercial and research interest directed toward the inland culture of Pacific white shrimp, Litopenaeus vannamei. Most work to date has been conducted in greenhouses, where photoautotrophic organisms are significant contributors to system functionality. In more temperate locations, operations in insulated buildings would reduce heating costs. This experiment was designed to evaluate the effect of light on shrimp cultured in intensive biofloc systems. A 92‐d experiment was conducted in 3.8‐m3 tanks. There were five light treatments: (1) natural sunlight (SUN) as a control (midday: 718 lx); (2) one metal halide light (MHL) (1074 lx); (3) one fluorescent light (1FL) (214 lx); (4) two fluorescent lights (2FL) (428 lx); and (5) three fluorescent lights (3FL) (642 lx). Artificial light treatments operated on a 12:12 daily cycle. There were three replicate tanks per treatment and each was separated by black plastic to prevent light transmission between replicates. Each tank was stocked at 465 shrimp/m2 of tank bottom (initial mean weight = 0.4 g). Light treatment had a significant (P≤ 0.05) impact on average individual weight, survival, harvest yield (kg/m2), and feed conversion ratio (FCR). Harvest yield and survival among shrimp in the SUN, MHL, and 1FL treatments were not significantly different. However, there was an inverse linear relationship (P≤ 0.05; R2 = 0.76) between the number of fluorescent fixtures and survival, which was related to greater concentrations of filamentous bacteria as the intensity of fluorescent light increased, causing gill fouling. Natural light and MHL did not result in high concentrations of filamentous bacteria. These results indicate that natural light, metal halide lighting, and/or relatively low levels of fluorescent lighting are suitable for indoor production of Pacific white shrimp in biofloc systems. Light spectrum and intensity can affect bacterial community structure, which has a profound effect on shrimp survival and production. 相似文献
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Chelsea Watts Leigh Anne Bright Shawn Coyle James Tidwell 《Journal of the World Aquaculture Society》2016,47(4):538-543
Largemouth bass (LMB), Micropterus salmoides, are a highly desirable food fish especially among Asian populations in large cities throughout North America. The primary production method for food‐size LMB (>500 g) has been outdoor ponds that require two growing seasons (18 mo). Indoor, controlled‐environment production using recirculating aquaculture system (RAS) technologies could potentially reduce the growout period by maintaining ideal temperatures year‐round. Researchers conducted a 26‐wk study to evaluate optimal stocking densities for growout of second‐year LMB to food‐fish size in an indoor RAS. LMB fingerlings (112.0 ± 38.0 g) were randomly stocked into nine 900‐L tanks to achieve densities of 30, 60, or 120 fish/m3 with three replicate tanks per density. The RAS consisted of a 3000‐L sump, ¼ hp pump, bead filter for solids removal, mixed‐moving‐bed biofilter for nitrification, and a 400‐watt ultraviolet light for sterilization. Fish were fed a commercially available floating diet (45% protein and 16% lipid) once daily to apparent satiation. At harvest, all fish were counted, individually weighed, and measured. Total biomass densities significantly increased (P ≤ 0.05) with stocking rate achieving 6.2, 13.2, and 22.9 kg/m3 for fish stocked at 20, 60, and 120 fish/m3, respectively. The stocking densities evaluated had no significant impact (P > 0.05) on survival, average harvest weight, or feed conversion ratio which averaged 92.9 ± 5.8%, 294.5 ± 21.1 g, and 1.8 ± 0.3, respectively. After approximately 6 mo of culture, LMB did not attain target weights of >500 g. Observed competition among fish likely resulted in large size variability and overall poor growth compared to second‐year growth in ponds. Additional research is needed to better assess the suitability of LMB for culture in RAS. 相似文献
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OBJECTIVE: To determine the clinical usefulness of cardiac event recording in evaluating dogs and cats with unexplained syncope, episodic collapse, or intermittent weakness. DESIGN: Retrospective study. ANIMALS: 58 dogs and 2 cats. PROCEDURE: Medical records and electrocardiographic rhythm strips obtained by cardiac event recordings were reviewed. Cardiac rhythm data from the event recordings were classified as diagnostic or nondiagnostic. Diagnostic yield was calculated by dividing the number of animals for which cardiac event recording was diagnostic by the total number of animals undergoing cardiac event recording. RESULTS: For 51 animals, cardiac event recording was classified as diagnostic; therefore, overall diagnostic yield was 85%. Diagnostic yield was lower for animals without underlying structural heart disease (75.5%) than for animals with structural heart disease (95.6%). A specific arrhythmia was identified as the cause of clinical signs in 18 of the 51 (35%) animals for which cardiac event recording was diagnostic. Cardiac arrhythmia was definitively excluded as the cause of clinical signs in the remaining 33 (65%) animals in which cardiac event recording was diagnostic. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that cardiac event recording had a high diagnostic yield in dogs and cats examined because of unexplained syncope, episodic collapse, or transient weakness and ataxia, regardless of whether animals did or did not have an underlying structural heart disease. Diagnostic yield of cardiac event recording was higher than that reported previously for Holter monitoring. 相似文献