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81.
Our intent was to evaluate clinically total hip arthroplasty in the dog using the same procedures and prostheses. We replaced 20 hips in 15 dogs of both sexes and various breeds, weights, and ages. All animals exhibited pain caused by degenerative joint disease of one or both coxofemoral joints. Using Amstutz's system of grading at a minimum of 12 months post-operatively, none of the hips replaced were graded poor, 12.5% were graded fair, 12.5% good, and 75% excellent. Loosening of prosthetic components was by far the most common problem encountered in this study. Luxations were virtually eliminated by the use of the Richards Canine II total hip replacement system. Infections were found to be directly proportional to surgery time, number of operations performed, or both. Component failure occurred only when the size of the prosthesis was not properly matched to the size of the dog. Although these problems still must be overcome, we conclude that total hip arthroplasty is a valuable adjunct to veterinary medicine in selected cases. 相似文献
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The paper, which is based on a visit to Bosnia in 1954 and onthe literature available, describes in detail ten of the principalsurviving sites or stations of Picea omorika (Pancic) Bollein the Dinaric Alps and discusses the relationship of the treeto its present restricted environment. The main conclusionsare that the spruce, which is a relic in the flora of the BalkanPeninsula, succumbs to competition with other species and ispoorly adapted to its present environment but holds its ownwhen competition is absent as on north-facing cliffs or screesor where it has regenerated itself after fire or exploitation. 相似文献
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The Montserrat series is one of the most fertile of tropical soils. Substantial amounts of exchangeable K, available P, and favourable organic matter content and distribution contribute to its unique properties. P occurs in amounts ranging from 0.4 to 0.6 per cent, about 75 per cent of which is inorganic with Fe phosphates making up the bulk. Truog's reagent almost quantitatively extracts Ca phosphate and Bray's and Olsen's reagents extract mainly Al phosphate. Exchangeable K is derived from glauconite. High exchangeable Ca and Mg contents derived from weathering of carbonates impart a favourable pH to the soil for plant growth. Exceptional structural stability to 120 cm depth is associated with high free iron oxide, organic matter, and Ca contents. The outstanding feature in mineral weathering is the rapid transformation of glauconite through vermiculite to kaolinite and the formation of goethite. Considerable interlayering occurs between vermiculite with sesquioxide coatings and mica-vermiculite interlayers. Much of this weathering occurs in the calcareous, oxidized, friable parent rock. The features of the Montserrat series described above substantiate its classification as a Brown Earth (Mollisol). 相似文献
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Cadmium sorption was measured in 10 agricultural soils with pH ranging from 4.5 to 7.9, and total Cd content from 0.27 to 1.04 μg g?1 dry soil. With initial Cd concentrations of 0.5 to 100.0 μM, sorption from 0.002 M CaCl2 was described by the Freundlich adsorption equation but the gradients of the isotherms increased when the initial concentrations were below 0.5 μm. This indicates that there are specific sites of differing sorption energy; differences between soils in the gradients of the isotherms at low initial concentration could largely be accounted for by their contents of ‘free’ Fe2O3. When initial concentrations were below 0.5 μm there was a linear relationship between the quantity of Cd sorbed and the final concentration in solution. This relationship held with all soils except that of lowest pH from which there was a net loss of Cd to the solutions. Desorption was measured from three soils with contrasting pH. With the soil of lowest pH, over 80 per cent of sorbed Cd was desorbed to 0.002 m CaCl2 and up to 30 per cent to 100 or 500 μm solutions of heavy metal chlorides. In contrast, only very small proportions (<1.25 per cent) were desorbed from the other soils with pH 6.7 and 7.8. The results indicate that Cd is strongly sorbed by soils of pH of above 6.0 when added in amounts comparable to additions in sewage sludges or phosphatic fertilizers, and illustrate the importance of liming as a means of reducing the mobility of this metal in soils. 相似文献
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Emily C. COOLEDGE David R. CHADWICK Lydia M. J. SMITH Jonathan R. LEAKE Davey L. JONES 《农业科学与工程前沿(英文版)》2022,9(2):245