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31.
Allelopathic potential of watermelon in hydroponic culture was investigated using the continuous root exudates trapping system (CRETS). Laboratory bioassays and high-performance liquid chromatography (HPLC) were used for quantification of phytotoxins in different plant tissues and root exudates collected using XAD-4 resin. Seedling growth of both watermelon and lettuce was significantly inhibited by watermelon root exudates and the degree of inhibition increased with increasing concentration of exudates. Root exudates had inhibitory effects throughout the experiment and these were most pronounced during the period 41–50 days after transplanting. Inhibitory effects of various plant tissues were demonstrated using the bioassay tests. Frulic acid was the dominant component found using HPLC and the amounts of allelochemicals found in the plant extracts were correlated with the bioassay results using the Petri dish test. The results indicate that the allelopathic potential of watermelon may play an important role in the phenomenon referred to as ‘soil sickness’. 相似文献
32.
LAUREL A. DEGERNES DVM Diplomate ABVP SIMON C. ROE BVSc PhD Diplomate ACVS C. FRANK ABRAMS Jr. PhD PE 《Veterinary surgery : VS》1998,27(4):301-306
Objective —To measure pullout strength of four pin types in avian humeri and tibiotarsi bones and to compare slow-speed power and hand insertion methods.
Study Design —Axial pin extraction was measured in vitro in avian bones.
Animal Population —Four cadaver red-tailed hawks and 12 live red-tailed hawks.
Methods —The pullout strength of four fixator pin designs was measured: smooth, negative profile threaded pins engaging one or two cortices and positive profile threaded pins. Part 1: Pins were placed in humeri and tibiotarsi after soft tissue removal. Part 2: Pins were placed in tibiotarsi in anesthetized hawks using slow-speed power or hand insertion.
Results —All threaded pins, regardless of pin design, had greater pullout strength than smooth pins in all parts of the study ( P < .0001). The cortices of tibiotarsi were thicker than the cortices of humeri ( P < .0001). There were few differences in pin pullout strengths between threaded pin types within or between bone groups. There were no differences between the pullout strength of pins placed by slow-speed power or by hand.
Conclusions —There is little advantage of one threaded pin type over another in avian humeri and tibiotarsi using currently available pin designs. There were few differences in pin pullout strengths between humeri and tibiotarsi bones. It is possible that the ease of hand insertion in thin cortices minimizes the potential for wobbling and therefore minimizes the difference between slow-speed drill and hand insertion methods.
Clinical Relevance —Threaded pins have superior bone holding strength in avian cortices and may be beneficial for use with external fixation devices in birds. 相似文献
Study Design —Axial pin extraction was measured in vitro in avian bones.
Animal Population —Four cadaver red-tailed hawks and 12 live red-tailed hawks.
Methods —The pullout strength of four fixator pin designs was measured: smooth, negative profile threaded pins engaging one or two cortices and positive profile threaded pins. Part 1: Pins were placed in humeri and tibiotarsi after soft tissue removal. Part 2: Pins were placed in tibiotarsi in anesthetized hawks using slow-speed power or hand insertion.
Results —All threaded pins, regardless of pin design, had greater pullout strength than smooth pins in all parts of the study ( P < .0001). The cortices of tibiotarsi were thicker than the cortices of humeri ( P < .0001). There were few differences in pin pullout strengths between threaded pin types within or between bone groups. There were no differences between the pullout strength of pins placed by slow-speed power or by hand.
Conclusions —There is little advantage of one threaded pin type over another in avian humeri and tibiotarsi using currently available pin designs. There were few differences in pin pullout strengths between humeri and tibiotarsi bones. It is possible that the ease of hand insertion in thin cortices minimizes the potential for wobbling and therefore minimizes the difference between slow-speed drill and hand insertion methods.
Clinical Relevance —Threaded pins have superior bone holding strength in avian cortices and may be beneficial for use with external fixation devices in birds. 相似文献
33.
Steve C. Haskins DVM MS H. Orima Y. Yamamoto John D. Patz BA 《Journal of Veterinary Emergency and Critical Care》1991,1(2):55-60
The ability of the SAV 6 high-frequency jet ventilator to effectively ventilate three anesthetized, paralyzed cats (3.2–4.2 kg), two small dogs (7.2 and 10.0 kg), six medium-sized dogs (20.5–25.0 kg), and three large dogs (36.0–43.0 kg) via a 14-gauge (dogs) or a 16-gauge (cats) catheter placed percutaneously into the trachea via the cricothyroid membrane or into a preplaced endotracheal tube was evaluated. The lowest driving pressure within the range of 0.25 to 2.0 kg/cm2 (1 kg/cm2 = 14.2 psi) and the highest cycle rate within the range of 60 to 240 per minute that would generate a PaCO2 of 30 ± 3 mm Hg were determined.
All animals could be ventilated to a PaC02 of 30 ± 3 mm Hg by the endotracheal tube and transtracheal route, except the largest dogs, which couid be ventilated to an average PaC02 of 36 mm Hg by the transtracheal route. The transtracheal route consistently required higher driving pressures and lower cycle rates than did the endotracheal tube route. Cats could be ventilated with a driving pressure of 0.25 kg/cm2 ; small dogs could be ventilated with 0.5 to 1.0 kg/cm2 ; medium-sized dogs with 1.0 to 1.5 kg/cm2 ; and large dogs with 1.5 to 2.0 kg/cm2 .
The SAV 6 high-frequency jet ventilator can effectively ventilate cats and dogs (7.2–43.0 kg) via a transtracheal catheter and an endotracheal tube. 相似文献
All animals could be ventilated to a PaC0
The SAV 6 high-frequency jet ventilator can effectively ventilate cats and dogs (7.2–43.0 kg) via a transtracheal catheter and an endotracheal tube. 相似文献
35.
Perception of Teaching and Assessing Technical Proficiency in American College of Veterinary Surgeons Small Animal Surgery Residency Programs 下载免费PDF全文
36.
C.B. Johnson BVSc PhD DVA Diplomate ECVA MRCA MRCVS M. Bloomfield P.M. Taylor MA VetMB PhD DVA Diplomate ECVA MRCA MRCVS 《Veterinary surgery : VS》1999,28(5):380-385
OBJECTIVE: To investigate the effects of ketamine on the electroencephalogram (EEG) of the horse. STUDY DESIGN: Prospective experimental study. ANIMALS: Eight Welsh mountain pony geldings weighing between 280 and 330 kg, 5 to 9 years old. METHODS: During halothane anesthesia at an end-tidal halothane concentration between 0.75 and 0.85%, the EEG frequency power spectrum and the auditory evoked potential were recorded while an infusion of ketamine was given. Ketamine 200 mg was infused over 5 minutes in 8 ponies. The effects of ketamine on the EEG were recorded continuously during the infusion and for a further 55 minutes. RESULTS: The ketamine infusion produced a plasma ketamine concentration that was significantly greater than the baseline until 7 minutes after the start of the infusion. The highest recorded ketamine concentration was 4.2+/-1.1 microg/ml recorded at 5 minutes after the start of the infusion. The spectral edge and median frequency of the EEG and the midlatency of the auditory evoked potential were compared with those recorded before the start of the infusion. The spectral edge, median frequencies and mid-latency of the auditory evoked potential were reduced by 21+/-13%, 31+/-20% and 19+/-36% respectively (mean +/- SD). Only the reduction in spectral edge frequency reached statistical significance. CONCLUSIONS: These results compared with those from other anesthetic and sedative agents suggest that the spectral edge frequency is an indicator of general central nervous system depression whereas the median frequency may be an indicator of antinociception. 相似文献
37.
R. J. TODHUNTER BVSc MS PhD Diplomate ACVS K. P. FREEMAN DVM PhD A. E. YEAGER dvm G. LUST PhD 《Veterinary surgery : VS》1993,22(5):330-342
This study assessed the effects of postoperative exercise and intra-articular polysulfated glycosaminoglycan (PSGAG) on the repair of osteochondral defects in the carpal joints of ponies. Eighteen ponies with normal carpi had osteochondral defects (mean dimensions 2.4 cm × 0.9 cm) created arthroscopically on the dorsal aspect of the distal articular surface of the radial carpal bone. The ponies were randomized (while balancing for age [range, 2 to 15 years; median, 5.0 years]) to two groups—nine ponies were exercised and nine were stall confined. Beginning at surgery, six ponies in each group received five weekly intra-articular injections of PSGAG (250 mg) in one joint and lactated Ringer's solution in the contralateral joint; the remaining three ponies in each group received lactated Ringer's solution in both joints. The incremental exercise schedule on a circular, rotating walker was begun six days after surgery and occurred twice daily, reaching a maximum of 0.7 miles of walking and 2.7 miles of trotting by the third postoperative month. The effects of treatment on the joint tissues were determined by weekly lameness examinations and measurement of the range of carpal joint motion, carpal radiographs at six and 17 weeks after surgery, synovial fluid analysis, and cytologic evaluation of alcohol-fixed synovial fluid specimens at weeks 1 through 4 and week 17, and histology of the synovial membrane. Ultrasound images of the carpi were acquired before operation and at weeks 1, 2, 4, 8, 10, 13, and 17. Ponies were euthanatized 17 weeks after surgery. Exercise, without medication, caused more lameness throughout the study compared with no exercise. Exercised, nonmedicated ponies had the greatest limitation to carpal flexion (more painful joints), and nonexercised, nonmedicated (control) ponies had the least limitation to flexion. Radiographic scores indicated that the exercised, nonmedicated ponies had significantly (p < .05) more signs of osteoarthritis than exercised, medicated and control ponies. Ultrasonographic measurements indicated that exercise, without medication, caused the greatest increase in combined measurement of the joint capsule thickness and synovial fluid accumulation at all postoperative times. Synovial lining cell numbers in the synovial fluid from exercised ponies were significantly (p < .05) higher than in nonexercised ponies at week 1, and this trend continued at weeks 4 and 17 (p < .1). There were significantly (p < .05) more morphologic abnormalities in the synovial lining cells from exercised than from nonexercised ponies at week 17. Medication with PSGAG enabled exercised carpal joints to be flexed significantly further from weeks 2 through 6 compared with nonmedicated joints. Medication significantly (p < .05) reduced the combined joint capsule and synovial fluid thickness at weeks 4, 8, and 13 compared with nonmedicated joints. On histologic examination, the synovial membrane matrix of exercised, medicated joints had significantly less chronic inflammatory changes than joints receiving other treatments. The authors concluded that this level of exercise was too intense when superimposed on large osteochondral defects in the carpus because it induced osteoarthritis. Polysutfated gtycosaminoglycan ameliorated the clinical signs of osteoarthritis in the exercised ponies. However, PSGAG was also associated with the formation of cartilage repair tissue that contained less type II relative to type I collagen compared with repair tissue from nonmedicated joints. 相似文献
38.
Laryngeal mask airway and transient hypercapnic hyperpnea for video‐endoscopic assessment of unilateral laryngeal paralysis in dogs 下载免费PDF全文
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