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排序方式: 共有309条查询结果,搜索用时 390 毫秒
291.
Spinal anaesthesia of 20 does undergoing laparotomies was accomplished with epidural injections of 2 per cent lignocaine at a dosage of 1 ml per 4.55 kg in 16 goats. Epidural injection resulted in paralysis lasting 198.5 minutes +/- 36.6 minutes. Subarachnlid injection resulted in paralysis lasting 180.8 minutes +/- 44.9 minutes. Xylazine was given intramuscularly at the dosage of 0.11 mg per kg after posterior paralysis was complete. These treatments resulted in effective analgesia for surgical intervention. Recovery was complete and uneventful in all goats. An additional 26 operations were performed using this treatment and results were equally satisfactory. 相似文献
292.
A mastitis control program carried out in 35 commercial dairy heards over three years increased the milk produced by 343 kg per cow per year and the amount of butterfat by 15.8 kg per cow per year, giving a net benefit of $16.10 per cow per year by the end of the third year. The net benefit is considerably understated since benefits other than the increase in milk production were not quantified. The overall disposal rate of 33 herds showed a drop from 19.3% in year 1 to 13.6% in year 3. An analysis of culling records showed that as the severity of mastitis increased so did cow age. 相似文献
293.
N was applied at 50, 100 or 150 mg l?1 in factorial combination with P at 7.5, 15 or 22.5 mg l?1 to asparagus seedlings. There were 6 successional harvests. N and P increased shoot dry weight by increasing mean dry weight and number of shoots. Increasing P had no effect on shoot growth at 50 mg l?1 N. N increased root dry weight (crown and roots) by increasing root number, whereas P decreased root dry weight due to a decrease in mean root dry weight. N increased total plant dry weight, but P had no effect. N and P increased the partitioning of dry weight to the shoots, while partitioning to the roots increased with time. Plant analysis revealed that 2.6–2.7% N and 0.29–0.36% P, on a dry-weight basis, were present in the shoots at the later harvests with the higher concentrations of N and P. 100–150 mg 1?1 N in combination with 15 mg l?1 P produced a seedling suitable for transplanting into commercial fields at 6 weeks from emergence. 相似文献
294.
Estimating primary productivity of forested wetland communities in different hydrologic landscapes 总被引:5,自引:0,他引:5
Five forested wetland sites in western Kentucky with hydrologic regimes varying from seasonally to continuously flooded were investigated for net above-ground biomass productivity (litterfall plus biomass growth) and for possible indicators of that productivity, including abiotic (flooding frequency and depth, phosphorus concentrations in water and sediments) and biotic (biomass, tree density, basal area, structural complexity, and mean height) indices. Net biomass productivity ranged from 205 g m-2y-1 for a stagnant semipermanently flooded Taxodium swamp to 1,334 g m-2y-1 in a bottomland forest along the Ohio River. Productivity was highest in wetlands with pulsing hydroperiods, intermediate with slowly flowing systems, and lowest with stagnant conditions. Surface water flooding of the wetlands during the growing season ranged from 17 to 100 percent of the year and did not predict productivity. Phosphorus concentrations in water and in sediments were not correlated to one another and did not, by themselves, predict productivity. No single abiotic variable predicted the exact ranking of productivity of the sites. Of the biotic variables, average tree diameter was inversely related to productivity. 相似文献
295.
Cardiopulmonary effects of continuous intravenous infusion of guaifenesin, ketamine, and xylazine in ponies 总被引:3,自引:0,他引:3
S A Greene J C Thurmon W J Tranquilli G J Benson 《American journal of veterinary research》1986,47(11):2364-2367
Eight ponies were anesthetized with a solution containing 50 mg of guaifenesin, 1 mg of ketamine, and 0.5 mg of xylazine X ml-1 of 5% dextrose in water. Anesthesia was induced by IV injection (1.1 ml X kg-1), followed by continuous IV infusion at 2.75 ml X kg-1 X hr-1. Heart rate, rate-pressure product, mean pulmonary artery pressure, and standard bicarbonate were not significantly changed throughout the study. Systolic, diastolic, and mean arterial pressures and left ventricular stroke work index were significantly decreased at 5 and 15 minutes after a bolus of the anesthetic solution was injected. Systolic blood pressure returned to within the base-line range at 30 minutes, but diastolic and mean arterial pressures were significantly decreased throughout the study. Cardiac index and arterial pH were decreased at 5 minutes only. Systemic vascular resistance was significantly decreased 60 minutes after bolus injection was given. Hypoventilation, as indicated by increased PaCO2, occurred 5 minutes after bolus injection was given. 相似文献
296.
Christopher R Gregory Kenneth S Latimer Kate E Pennick Keith Benson Tiffany Moore 《Journal of veterinary diagnostic investigation》2006,18(2):208-211
Intracytoplasmic inclusion bodies suggestive of iridovirus infection were observed in formalin-fixed, paraffin-embedded tissues from a nautilus (Nautilus spp.) that died without premonitory signs. Transmission electron microscopy revealed enveloped, hexagonal, viral particles that measured approximately 176 nm in diameter. Virions contained a dense central core and morphology typical of iridoviruses. Extracted DNA was amplified using primers homologous to conserved iridovirus sequences. The amplicons were cloned, sequenced, and determined to be approximately 60% similar to reported amphibian iridovirus sequences. A polymerase chain reaction-generated digoxigenin probe was used to detect viral nucleic acid in tissue sections by DNA in situ hybridization and high-affinity cytochemistry. The detected nucleic acid corresponded to the inclusion bodies observed microscopically. This represents a novel iridovirus of mollusks. 相似文献
297.
Milton SV Gluskin E Arnold ND Benson C Berg W Biedron SG Borland M Chae YC Dejus RJ Den Hartog PK Deriy B Erdmann M Eidelman YI Hahne MW Huang Z Kim KJ Lewellen JW Li Y Lumpkin AH Makarov O Moog ER Nassiri A Sajaev V Soliday R Tieman BJ Trakhtenberg EM Travish G Vasserman IB Vinokurov NA Wang XJ Wiemerslage G Yang BX 《Science (New York, N.Y.)》2001,292(5524):2037-2041
Self-amplified spontaneous emission in a free-electron laser has been proposed for the generation of very high brightness coherent x-rays. This process involves passing a high-energy, high-charge, short-pulse, low-energy-spread, and low-emittance electron beam through the periodic magnetic field of a long series of high-quality undulator magnets. The radiation produced grows exponentially in intensity until it reaches a saturation point. We report on the demonstration of self-amplified spontaneous emission gain, exponential growth, and saturation at visible (530 nanometers) and ultraviolet (385 nanometers) wavelengths. Good agreement between theory and simulation indicates that scaling to much shorter wavelengths may be possible. These results confirm the physics behind the self-amplified spontaneous emission process and forward the development of an operational x-ray free-electron laser. 相似文献
298.
R. E. Anderson A. P. Benson W. J. Hooker Gerard S. Birth Karl H. Norris Reiner Bonde Robert Akeley Donald Merriam C. C. Craft H. W. Siegelman W. L. Butler L. A. Dionne G. D. Easton R. H. Larson R. W. Hougas H. T. Erickson J. Galindo M. E. Gallegly 《American Journal of Potato Research》1958,35(2):421-423
299.
E.M. Pritchett A.G. Rogers M.P. Caputo E.R. Benson R.L. Alphin A.L. Johnson 《Research in veterinary science》2014
Stress in poultry can produce many undesirable effects on bird health and production performance. The objective of this study was to develop and evaluate a potential measure to assess stress through analysis of brain activity using electroencephalography (EEG). In two experiments, White Pekin ducks were implanted with EEG transmitters and treated with potential stressors in a chamber or in their pens. Electrocardiograms and blood corticosterone levels were collected as standard measures of stress. EEG analysis showed an increase in the relative delta frequency and a decrease in the relative alpha frequency during the treatment period for shock (P < 0.05). EEG analysis of the second experiment showed no differences between time periods for all frequencies for all treatments. Based on these results, EEG is currently not a viable technique for the measurement of acute stress in commercial poultry. 相似文献
300.
Gabriela Rojas‐Temahuay Sarah Crain Catherine Benson Leslie Sharkey Geneva Nothnagel 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2014,43(3):330-336
A 5‐year‐old neutered male Mastiff and an 8‐year‐old spayed female Labrador Retriever were presented to the University of Minnesota Veterinary Medical Center. The Mastiff was presented for evaluation of lameness and pyoderma one month prior in Missouri, where he tested positive for Ehrlichia canis by serum ELISA test, treated with doxycycline. PCR for Ehrlichia sp, Anaplasma sp, Babesia sp, and Bartonella sp, and PCR for antigen receptor rearrangement were negative, serum protein electrophoresis (SPE) revealed polyclonal gammopathy, and mildly reactive lymphoid cells were seen cytologically. The Labrador presented with a proliferative rostral mandibular gingival mass and lipomas for further presurgical evaluation of cold agglutinin activity documented by a commercial laboratory 2 years earlier prior to removal of a grade II mast cell tumor. This dog had a negative SNAP4Dx, normal SPE, and persistently increased serum ALP activity and polyuria/polydipsia suggestive for hyperadrenocorticism. Both dogs had markedly agglutinated RBC in the EDTA samples that dispersed with warming, and normal plasma color. Cold agglutinin activity was demonstrated by direct saline agglutination testing using whole blood and washed erythrocytes demonstrating agglutination at 30°C, 25°C, 15°C, and 4°C, but not at 37°C . CBC results (ADVIA 2120i) from the Mastiff revealed no significant differences in the RBC results obtained at room temperature (RT) and at 37°C; however, the RT run demonstrated negative bias in neutrophil and platelet concentrations attributed to rapid RBC settling. This uncommon hematologic condition may cause artifacts on the automated leukogram and platelet count, and may be subclinical for long periods. 相似文献