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排序方式: 共有348条查询结果,搜索用时 625 毫秒
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Nicholas J. Macdonald BVetMed Carolyn A. Burton BVetMed PhD Robert N. White BSc BVetMed 《Veterinary radiology & ultrasound》2002,43(6):534-540
A visual analog scale and a numeric scoring scale were designed for the assessment of dynamic intraoperative mesenteric portovenography in the dog and cat. Two independent observers evaluated both scoring scales for reproducibility (differences between observers) and repeatability (within-observer differences) in the assessment of 60 trial portovenograms. Agreement (interchangeability) of both scales was evaluated by comparing the scores obtained in the assessment of 200 portovenograms obtained from 100 dogs and cats. There was no statistical difference between the two observers when scoring the same portovenogram for either the visual analog scale (p = .730, reproducibility coefficient = 17.85 units) or the numeric scoring scale (scores identical, reproducibility coefficient = 0). There was no statistical difference, for either of the observers, when the same portovenogram was assessed on two separate occasions using the visual analog scale (observer 1, p = .35, repeatability coefficient = 17.93 units; observer 2, p = .42, repeatability coefficient = 8.27 units) or the numeric scoring scale (scores given by both observers were identical, repeatability coefficient = 0 for both observers). The results of comparison between the visual analog scale and numeric scoring scale confirmed that the two scoring systems were not directly interchangeable. Although both scoring systems demonstrated good reproducibility and repeatability, the numeric scoring scale possessed a number of inherent deficiencies that suggested it was not the method of choice for the assessment of the subjective data obtained from dynamic intraoperative mesenteric portovenography. 相似文献
33.
AG Loeser Z Shen DS Dessau DS Marshall CH Park P Fournier A Kapitulnik 《Science (New York, N.Y.)》1996,273(5273):325-329
Angle-resolved photoemission experiments reveal evidence of an energy gap in the normal state excitation spectrum of the cuprate superconductor Bi2Sr2CaCu2O8+delta. This gap exists only in underdoped samples and closes around the doping level at which the superconducting transition temperature Tc is a maximum. The momentum dependence and magnitude of the gap closely resemble those of the dx2-y2 gap observed in the superconducting state. This observation is consistent with results from several other experimental techniques, which also indicate the presence of a gap in the normal state. Some possible theoretical explanations for this effect are reviewed. 相似文献
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Naruepon Kampa DVM Ursula Wennstrom DVM Peter Lord BVSc FRCVS Robert Twardock DVM PhD Enn Maripuu BSc Per Eksell DVM PhD Sten-Olof Fredriksson BSc 《Veterinary radiology & ultrasound》2002,43(4):383-391
Determinations of different methods of measurement of uptake of 99mTc-DTPA using scintigraphy of glomerular filtration rate (GFR) were made from 29 studies on 10 healthy beagle dogs. GFR was measured by calculating the percentage dose uptake (integral method) and rate of uptake (slope method) of 99mTc-DTPA using manual kidney regions of interest (ROI) and automatic kidney and background ROIs at different time periods of the uptake phase. These results were compared using linear regression analysis to the GFR obtained from 99mTc-DTPA plasma clearance using multiple blood samples. The best correlation coefficient between percentage DTPA uptake and GFR by DTPA clearance (r = 0.84, P < 0.001) was derived from time intervals between 30s-120s with a perirenal background ROI at 1 or 2 pixels out from the kidney ROI using automatic kidney ROI at 20% threshold. With the slope method, the best correlation coefficient (r = 0.85, P < 0.001) was obtained from time intervals between 30s-peak with the background ROI at 2 pixels out from the kidney ROI using automatic ROI at 35% threshold. The offset was higher, and the correlation varied more with different ROIs and the method was unreliable at time intervals extending beyond the peak radioactivity. Manual kidney ROIs with automatic background ROIs had slightly lower correlations. With DTPA renography both integral and slope uptake method with automatic kidney and background ROIs are accurate methods to estimate the GFR, but that the integral method is much more stable to variations in ROI size and the duration of the uptake phase of the renogram. 相似文献
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Gail I. Anderson BVSc MSc PhD Diplomate ACVS Kent Orlando BSc DDS James P. Waddell MD FRCS 《Veterinary surgery : VS》2001,30(4):311-318
OBJECTIVE: To establish whether hydroxyapatite (HA) coatings applied to metal total-hip-replacement components increased synovitis in the coxofemoral joint of dogs. Study Design-An in vivo research trial and histologic study. ANIMALS: Twenty-three large, mixed-breed dogs. METHODS: Arthroplasty components were implanted with HA on neither stem nor cup, or with HA applied to either the femoral component or with both stem and cup having HA applied in 23 dogs. Synovial inflammation was scored 3, 6, and 12 months after surgery. Synovial membrane thickness; polyethylene particulate load; fibrin exudate; membrane edema; mitotic index; giant-cell, mononuclear histiocyte, lymphocyte, and polymorph number; and collagen degeneration were scored and statistical analyses performed. RESULTS: Operated-side synovial thickness was greatly increased relative to control. Fibrin deposition, intramembranous edema, and collagen degeneration were similar within each time interval among the various component groups. The majority of inflammatory scores among the groups were unchanged. In this 12-month study, the presence of HA coatings appear not to have a marked impact on the development of synovial inflammation. CONCLUSIONS: HA-coated components do appear to contribute somewhat to the inflammatory load within the periprosthetic environment, but this effect is not marked. CLINICAL RELEVANCE: The major advantage of HA addition to arthroplasty components is enhanced osteoconductivity around metallic surfaces. The slight increase in particulate load seen in the presence of HA coatings may contribute to the development of aseptic loosening of arthroplasty components, but is unlikely to be the major causative factor. 相似文献
38.
G. Obolensky Ing. Agr. BSc MSc Dr. Ing. DSc. 《Plant foods for human nutrition (Dordrecht, Netherlands)》1960,7(3):273-288
Summary 1) Some aspects of transplantation of embryo pieces of one species, into the embryo of an other one were discussed, as well as the grafting of an embryo on the endosperm of other varieties, species and even genera (vegetative hyberidization).2) Deep hereditary changes were observed, as well as an incompatibility (negative tropism) to assimilate and to fuse between the embryonic tissues of different species.3) But a positive tropism with a complete assimilation of the tissue can also be observed in all those cases, when the grafted endosperm, belonged to the same species as the one of the transplanted embryo piece.4) This method should be extended in order to produce oil seed crops and particularily soja beans, ripening in northern long day regions (change from short day to long day photoperiodism).5) Ultrasonic vibrations could be usefully applied to improve this grafting method.
Resume 1) Quelques aspects de transplantation d'un fragment d'embryon d'une espèce, dans celui d'une autre, ont été discutés, ainsique le gréffage d'un embryon, sur les réserves nutritives (endosperme) d'autres variétés, espèces et mêmes genres (hybridation végétative).2) Des changements héréditaires profonds ont pu être observés, ainsiqu'une incompatibilité (tropisme négative) de s'assimiler et de fusionner entre les tissus embryonaires de différentes espèces.3) Quand-même un tropisme positif, accompagné d'une assimilation complète des tissues, put être observé dans tous ces cas, ou la réserve nutritive (endosperme) appartenait à la même espèce que le fragment transplanté.4) Cette méthode devrait être approfondie pour pouvoir produire des plantes oléagineuses, en particulier du soja, qui puisse mûrir dans des régions nordiques aux jours longs, pendant la saison de croissance (changement d'un phototropisme de jours courts à celui de jours longs).5) Un traitement aux Ultra-Sons pourrait être avantageusement appliqué afin d'améliorer cette méthode.相似文献
39.
QUALITATIVE AND QUANTITATIVE THYROID IMAGING IN FELINE HYPERTHYROIDISM USING TECHNETIUM-99M AS PERTECHNETATE 总被引:1,自引:0,他引:1
Carmel T. Mooney MVB MPhil Keith L. Thoday BVetMed Phd DVD Jeremy J. Nicoll BSc Phd David L. Doxey BVM&S PhdD 《Veterinary radiology & ultrasound》1992,33(5):313-320
Thyroid imaging using technetium-99m as pertechnetate (99m TcO4 ) was carried out in five healthy, euthyroid and 37 hyperthyroid cats using both pinhole and parallel-hole collimators. Images of greater resolution, necessary to distinguish bilateral lobe involvement, were obtained using the pinhole collimator. Per cent thyriod 99m TcO4 - uptake was calculated in each cat and was significanly (P < 0.001) higher in hyperthyroid compared with euthyroid cats. In the hyperthyroid cats, per cent thyroid uptake was significantly correlated with serum total thyroxine (T4) and triiodothyronine (T3) Concentrations. Per cent thyroid 99m TcO4 - uptake is increased in feline hyperthyrodism and may be calculated using a pinhole collimator alone at the time of qalitative assessment of the extent of thyroid tissue involvement. 相似文献
40.
PAUL W. MORGAN DVM DVSc ALLEN G. BINNINGTON DVM MSc Diplomate ACVS CRAIG W. MILLER DVM MVSc Diplomate ACVS DALE A. SMITH DVM DVSc ANNE VALLIANT BSc JOHN F. PRESCOTT MA Vet MB PhD 《Veterinary surgery : VS》1994,23(6):494-502
This project compared the effects of hydrocolloid (HC) and hydrogel (HG) occlusive dressings and a polyethylene (PE) semi-occlusive dressing on the healing of acute full-thickness skin wounds on the forelimbs of 10 dogs. All treatments resulted in a similar degree of healing at postoperative days 4 and 7. No significant differences existed in the number of wounds that were more than 90% healed at postoperative day 28 between the group treated with the HG dressing and the group treated with the PE dressing. There were significantly fewer wounds more than 90% healed at postoperative day 28 in the group treated with the HC dressing. Wounds under the HG dressing had the largest mean percentage of contraction at postoperative days 21 and 28. Wounds under the HG dressing also had the largest contraction/re-epithelialization ratio (postoperative days 21 and 28) compared with wounds under the PE and HC dressings. Wounds under the PE dressing had a significantly higher mean percentage of re-epithelialization than wounds under both occlusive dressings on postoperative days 14, 21, and 28. Wounds under the two occlusive dressings had exuberant granulation tissue present more often than wounds under the PE dressing. The two occlusive dressings had significantly higher bacterial counts on wounds compared with wounds under the PE dressing; analysis of variance (ANOVA), P = .0008. Wounds under the HC dressing showed the poorest healing in all parameters. 相似文献