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51.
The pin holding strengths of partially threaded and nonthreaded intramedullary pins were compared in an in vitro study. The mean percent holding strength of partially threaded pins to nonthreaded pins was 102%. No relationships could be determined when the holding strength of the pins was evaluated as a function of the dog's weight, bone length, and length of pin within the bone. It was concluded that no statistical difference in in vitro pin holding strength exists between the two types of pins. 相似文献
52.
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
53.
Ninety-nine isolates of obligate anaerobic bacteria obtained from clinical material were tested for susceptibility to ten antimicrobial agents. Regardless of the species of animal from which the isolates were obtained 90–95% were inhibited by ≤4 μg of ampicillin/ml, ≤4 μg of chloramphenicol/ml, ≤1 μg clindamycin/ml, ≤2 μg metronidazole/ml, ≤8 μg minocycline/ml, ≤16 μg penicillin Gyml, and ≤16 μg tetracycline/ml. All the aminoglycoside antibiotics tested (gentamicin, kanamycin, neomycin, and streptomycin) were shown to be relatively ineffective requiring ≥128 μg/ml for the inhibition of >50%of the isolates. The minimal inhibitory concentration of penicillin G and tetracycline tended to be higher for isolates from non-human primates (penicillin G) and ruminants (tetracycline). 相似文献
54.
T. KARAK R. Kumar PAUL R. Kumar BORUAH I. SONAR B. BORDOLOI A. K. DUTTA B. BORKOTOKY 《土壤圈》2015,25(2):316-328
Major chemical properties of tea-growing soils are of paramount importance for better management in a sustainable fashion.Therefore,this study was carried out to understand the major soil chemical properties of major tea(Camellia sinensis L.)-growing areas,Dibrugarh and Tinsukia districts,in the state of Assam,India.A total of 991 surface soil samples were collected from 15 large tea estates(TEs) for analysis of their major chemical properties.Soil pH ranged from 3.61 to 6.81.Total organic carbon and total nitrogen ranged from 2.4 to 47.3 and 0.24 to 3.60 g kg-1,respectively.All soils were sufficiently rich in plant-available potassium(as K2O),which ranged from 127.71 to 252.33 mg kg-1,exceeding the amount prescribed for optimum tea yield of > 100 mg kg-1.Plant-available sulfur among soil samples widely varied from 4 to 129 mg kg-1.Results of hierarchical clustering analysis for homogenous grouping of the 15 TEs based on soil chemical properties showed that the 15 TEs could be classified into three distinct groups which consisted of6,8 and 1 TEs,respectively.Based on the Kolmogorov-Smirnov(K-S) test,the best fitted theoretical probability distributions were found out for different soil chemical properties.It could be concluded that a balanced fertilizer application would be needed as a part of tea improvement program using soil chemical test. 相似文献
55.
PAUL J. KOZLOWSKI 《Growth and change》1987,18(3):62-73
ABSTRACT Indexes of leading indicators are used to forecast short-run changes in economic activity in many states and metropolitan areas. This article examines the forecasting performance of a sample of such regional indexes over several business cycles. Although these indexes vary across regions, the results show that they do provide forecasts of recessions and recoveries and also exhibit some potential for forecasting quantitative changes in regional employment. 相似文献
56.
ABSTRACT This article reports on an attempt to duplicate the results of “Regime, Polity, and Economic Growth: The Latin American Experience,” published in the Winter 1995 issue of Growth and Change. The original article used the Parks method to analyze cross section time series data, and concluded that after controlling for other relevant variables military governments have lower rates of economic growth than their civilian counterparts. Using data provided by the original researcher, and using various regression techniques including the Parks method, we were not able to reproduce the original results. We attribute this to problems in both the original data and regression techniques. 相似文献
57.
Innovation, use of high technology, and flexibility of response to customer needs are studied in two surveys of small manufacturing firms in New York and Pennsylvania. They are shown in both surveys to be separate and unrelated concepts. None of five industry-level classifications of high-technology firms, using SIC codes predict these concepts on a firm level. Only innovation is related to a sophisticated firm marketing program. and to export from the state. 相似文献
58.
MARTIN CASTONGUAY PETER V. HODSON CHRISTOPHER MORIARTY KENNETH F. DRINKWATER BRIAN M. JESSOP 《Fisheries Oceanography》1994,3(3):197-203
American eel (Anguilla rostrata) recruitment has declined dramatically, in parallel with that of European eel (Anguilla anguilla). Since both species spawn in the Sargasso Sea and migrate as larvae to continental waters, the coincidence in recruitment failure implies an Atlantic-wide cause, due perhaps to ocean climate. There is indirect evidence that the Gulf Stream has weakened in the 1980s. A slower Gulf Stream could interfere with larval transport and generate observed patterns of declining abundance of American eel only in northern North America and relatively uniform declines of European eel throughout Europe. While specific causes are still unclear, these data indicate a threat to both species and to their commercial fisheries. 相似文献
59.
NATASHA M. WERPY CHARLES P. HO ANTHONY P. PEASE CHRISTOPHER E. KAWCAK 《Veterinary radiology & ultrasound》2011,52(2):154-160
Six cadaver forelimbs were imaged in two high‐field magnetic resonance (MR) systems and one low‐field MR system following the creation of osteochondral defects on the palmar distal aspect of the third metacarpal bone. The following sequences were performed using all three systems: proton density (PD) turbo spin echo, T2* gradient echo (GRE), T2‐weighted fast spin echo, and short tau inversion recovery. In addition, 3D T1 GRE sagittal standard and motion insensitive sequences were obtained using the low‐field system. PD fat saturated and 3D T1‐weighted spoiled GRE images with and without fat suppression were acquired with the high‐field systems. Lesions were measured and assigned a confidence score. The images obtained using high‐field systems (1.0 and 1.5 T) more accurately represented the osteochondral defects when compared with low‐field system (0.27 T) images. The largest difference was observed when evaluating articular cartilage defects, which were not identified on the low‐field images. Sequence selection affected the appearance of the lesions. On all systems the turbo and fast spin echo sequences more accurately represented the lesion size and shape when compared with the GRE sequences. The T1 GRE sequence is the only sequence that appears to allow visualization of the articular cartilage on the low‐field images, but is limited in providing adequate cartilage visualization. Confidence scores were greater on the high‐field systems when compared with the low‐field system. 相似文献
60.