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排序方式: 共有261条查询结果,搜索用时 46 毫秒
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Wilson DV Lankenau C Berney CE Peroni DL Mullineaux DR Robinson NE 《Equine veterinary journal》2004,36(6):489-494
REASONS FOR PERFORMING STUDY: Acupuncture may be recommended for horses with 'heaves' because it is being increasingly applied to treat human asthma. Therefore, its efficacy was investigated in horses with this asthma-like disease. OBJECTIVE: To evaluate the efficacy of a single acupuncture treatment for the relief of airway obstruction in heaves-affected horses. METHODS: The efficacy of a single acupuncture treatment was tested in 10 heaves-affected horses, and the effect of removal from the dusty stall environment in 5 heaves-affected horses. Before treatment, horses were stabled to induce airway obstruction and, apart from trips to the laboratory for pulmonary function measurements, they remained stabled for the duration of each treatment. The severity of airway obstruction was quantified by measurement of lung function before treatment (baseline), and at 20, 60, 120 and 240 mins and 24 h after the following treatments administered in random order: halter restraint and patting, a single acupuncture treatment by an experienced acupuncturist, and a single acupuncture treatment using predetermined points (recipe) by a veterinarian with no acupuncture training. In a second study, horses were untreated and remained either in their stall or in a paddock for all measurements of lung function, after baseline readings were made. RESULTS: In the first study, after all treatments, there was a temporal improvement in maximal change in pleural pressure, pulmonary resistance, dynamic compliance, respiratory rate, and tidal volume that lasted less than 24 h. There was no specific effect of acupuncture treatment. In the second study, removal from the dusty environment did not produce an improvement in lung function in the first 6 h. We conclude that most of the improvements in lung function observed in the study were due to handling. CONCLUSIONS: Assessed objectively, a single acupuncture treatment during an attack of heaves causes no more improvement in lung function than does handling the horse. POTENTIAL RELEVANCE: Acupuncture should not replace conventional medical treatments for heaves. 相似文献
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The effect of four anesthetic protocols on splenic size in dogs 总被引:2,自引:1,他引:1
Wilson DV Evans AT Carpenter RA Mullineaux DR 《Veterinary anaesthesia and analgesia》2004,31(2):102-108
Objective To characterize the effects of four anesthetic protocols on the size of the spleen during surgery in dogs. Study design Prospective experimental trial. Animals Twenty‐four beagle dogs, 1.1 ± 0.3 years of age and weighing 10.9 ± 2.7 kg. Methods Dogs were allocated to receive one of four anesthetic protocols: 1 – pre‐medication with acepromazine and butorphanol, induction with thiopental; 2 – pre‐medication with acepromazine and butorphanol, induction with propofol; 3 – pre‐medication with medetomidine and butorphanol, induction with propofol; and 4 – pre‐medication with medetomidine and butorphanol, induction with ketamine and diazepam. Anesthesia was then maintained with halothane. At laparotomy, the spleen length, width, and height were measured, these were measured again just prior to closure of the abdomen. Splenic area and volume were calculated. Hematocrit and total serum protein (TSP) were measured before and after induction and during laparotomy. Results Splenic volume was greatest after protocol 4 (161.2 ± 40.2 cm3; p < 0.05) and was least after protocol 2. The differences in volume were because of differences in length, width, and height between groups. There was no significant change in area, length, or width over the study period. Hematocrit decreased significantly in all dogs but at different times. The decrease occurred after pre‐medication if acepromazine was administered, at induction following protocol 3 and during surgery following protocol 4. Conclusions If splenic volume is to be minimized during surgery, then acepromazine and propofol should be used in the anesthetic protocol. The administration of medetomidine, diazepam, and ketamine will produce a greater splenic volume. Lack of correlation between hematocrit and spleen size following the anesthetic protocols studied suggests sequestration of red blood cells in nonsplenic sites. 相似文献
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Wilson DV Kantrowitz A Pacholewicz J Salat O Paules BR Zhou Y Dawe EJ 《Veterinary surgery : VS》2000,29(1):106-118
OBJECTIVE: To describe perioperative management of calves that underwent left lateral thoracotomy, aortic cross-clamping, partial left heart bypass and implantation of a left ventricular assist device. SAMPLE POPULATION: A total of 43 healthy castrated male calves, weighing 121 +/- 24 kg. RESULTS: Diazepam (mean +/- SD, 0.26 +/- 0.07 mg/kg), ketamine (5.9 +/- 2.17 mg/kg) and isoflurane were used in the anesthetic management of calves undergoing implantation of a left ventricular assist device in the descending thoracic aorta. Other adjunctive agents administered were fentanyl (11 +/- 5.4 microg/kg), lidocaine (4.9 +/- 3.19 mg/kg), bupivacaine (0.75%) and butorphanol (0.49 +/- 0.13 mg/kg). None of the calves regurgitated at induction or during intubation. A tube was used to drain the rumen and prevent bloat during the procedure. Partial left heart bypass was used to perfuse the caudal half of the body during the period of aortic cross clamp and device implantation. Initial mean systemic blood pressure was 96 +/- 25 mm Hg, and pressures measured in the auricular artery increased during aortic cross-clamping and bypass. Vasoconstrictor therapy was required to treat caudal arterial hypotension during the procedure in 9 calves. Mean systemic arterial pressures returned to baseline values by the end of the anesthetic period. Initial mean pulmonary arterial pressures (PAP) were 22 +/- 3 mm Hg. A significant but transient increase in pulmonary arterial pressure occurred after both heparin and protamine administration. CONCLUSIONS: The described anesthetic protocol was effective for thoracotomy and implantation of an intra-aortic left ventricular assist device in normal calves. Partial left ventricular bypass was a useful adjunct during the period of aortic cross clamp. The doses of heparin and protamine administered were effective. Responsibility to monitor oxygenation of the cranial half of the animal continues during the bypass period as hypoxemia due to pulmonary dysfunction will not be detected by the perfusionist. 相似文献
98.
Kasumov AY Kociak M Guéron S Reulet B Volkov VT Klinov DV Bouchiat H 《Science (New York, N.Y.)》2001,291(5502):280-282
Conductivity measurements on double-stranded DNA molecules deposited by a combing process across a submicron slit between rhenium/carbon metallic contacts reveal conduction to be ohmic between room temperature and 1 kelvin. The resistance per molecule is less than 100 kilohm and varies weakly with temperature. Below the superconducting transition temperature (1 kelvin) of the contacts, proximity-induced superconductivity is observed. These results imply that DNA molecules can be conducting down to millikelvin temperature and that phase coherence is maintained over several hundred nanometers. 相似文献
99.
The 2011 magnitude 9.0 Tohoku-Oki earthquake: mosaicking the megathrust from seconds to centuries 总被引:5,自引:0,他引:5
Simons M Minson SE Sladen A Ortega F Jiang J Owen SE Meng L Ampuero JP Wei S Chu R Helmberger DV Kanamori H Hetland E Moore AW Webb FH 《Science (New York, N.Y.)》2011,332(6036):1421-1425
Geophysical observations from the 2011 moment magnitude (M(w)) 9.0 Tohoku-Oki, Japan earthquake allow exploration of a rare large event along a subduction megathrust. Models for this event indicate that the distribution of coseismic fault slip exceeded 50 meters in places. Sources of high-frequency seismic waves delineate the edges of the deepest portions of coseismic slip and do not simply correlate with the locations of peak slip. Relative to the M(w) 8.8 2010 Maule, Chile earthquake, the Tohoku-Oki earthquake was deficient in high-frequency seismic radiation--a difference that we attribute to its relatively shallow depth. Estimates of total fault slip and surface secular strain accumulation on millennial time scales suggest the need to consider the potential for a future large earthquake just south of this event. 相似文献
100.
Recycled subducted ocean crust has been traced by elevated 187Os/188Os in some studies and by high nickel and low manganese contents in others. Here, we show that these tracers are linked for Quaternary lavas of Iceland, strengthening the recycling model. An estimate of the osmium isotopic composition of both the recycled crust and the mantle peridotite implies that Icelandic Quaternary lavas are derived in part from an ancient crustal component with model ages between 1.1 _ 109 and 1.8 _ 109 years and from a peridotitic end-member close to present-day oceanic mantle. 相似文献