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41.
It is the purpose of this study to call attention to new bone production that often occurs early in the sequence of pathological changes associated with canine hip dysplasia. New bone production extending to bony remodeling, as well as femoral head subluxation, both occur in the sequence of pathologic changes associated with canine hip dysplasia. Subluxation is considered primary, while osteoarthrosis is a secondary feature, and both are used in the diagnosis of canine hip dysplasia. This report concerns the significance of the presence of a solitary bony osteophyte, or spur, that is frequently evident on the caudal aspect of the femoral neck as viewed on the conventional ventrodorsal projection. This report utilizes findings from pelvic radiographs of 605 dogs (five breeds). There was a greater frequency (54%)of this bony change in cases diagnosed radiographically as dysplastic than in cases diagnosed as normal(15%).Thus, it is suggested that this minimal radiographic change can be used as an indicator of early canine hip dysplasia, especially in the absence of subluxation of the femoral head. 相似文献
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44.
Demographic data and treatment of small companion animals with lead poisoning: 347 cases (1977-1986)
R V Morgan L K Pearce F M Moore T Rossi 《Journal of the American Veterinary Medical Association》1991,199(1):98-102
Three hundred forty-seven cases of lead poisoning in small animals, diagnosed after 1976, were reviewed. The types of treatments used and their outcomes were analyzed. Changes in blood lead concentrations following various treatments, as well as the sources of lead exposure, were also reviewed. The geographic origins of the cases were traced, and demographic factors were studied to determine possible correlates that might explain the regional distribution of cases. 相似文献
45.
Barry K. Cooke Pamela J. Herrington Kenneth G. Jones Norman G. Morgan 《Pest management science》1975,6(6):571-579
In 3 year field experiments on pest and disease control by mobile overhead spraying of intensive Cox's Orange Pippin apple trees, overhead booms applying 1125 litres/ha and overhead mist-blowing equipment applying 562 litres/ha, each spraying two complete rows from one alley in half the normal time, were compared with conventional automatic mast spraying at 2250 litres/ha and with conventional mist-blowing at 562 litres/ha. The overhead boom application of demeton-S-methyl (0.0036% a.i.) with azinphos-methyl (0.0165% a.i.) or of fenitrothion (0.031% a.i.) at the green cluster stage gave control of the applegrass aphid, Rhopalosiphum insertum, virtually equal to that obtained by conventional application of the same insecticides. Similarly, the overhead mist applications of conventional quantities of insecticides gave equal control, but not when applying one-quarter of the normal amount of insecticides. The conventional methods generally gave better control of apple sucker, Psylla mali. In 1971, when the incidence of apple scab, Venturia inaequalis, was only moderate, the overhead boom method gave equal control to conventional spraying with both dodine/captan (0.03% a.i. and 0.094% a.i.) and benomyl (0.025% a.i.) programmes: in 1972 and 1973, when the scab incidence was heavier, the overhead boom spraying was again equal to the conventional method with the benomyl programme but was less effective with the dodine/captan programme. The overhead mist applications gave control only when the scab incidence was light. Repeated applications of dinocap emulsion (0.025% a.i.), included in the fungicide programme in 1971, gave as good control of the active stages of fruit tree red spider mite, Panonychus ulmi, when applied by the overhead methods as by conventional spraying, but application of the benomyl programme gave poor control. Mobile overhead spraying of small intensive apple trees is a promising method but needs further development before becoming fully acceptable. 相似文献
46.
ABSTRACT Panicle and shoot blight, caused by a Fusicoccum sp., is an economically important disease of pistachio in California. Between 1999 and 2001, the disease severity was monitored throughout the growing season in 10 pistachio orchards, irrigated with drip, microsprinklers, low-angled (12 degrees ) sprinklers, or flood. The effect of temperature, precipitation pattern, irrigation system, and incidence of Fusicoccum sp. latent infection on panicle and shoot blight severity was quantified with a generalized linear model for repeated measures. The number of continuous rainy days in April and May and the cumulative daily mean temperatures from June to early September had a significant positive effect on panicle and shoot blight of pistachio leaves and fruit. Drip irrigation significantly decreased disease risk. Other factors, such as the number of discontinuous rainy days in April and May, the cumulative deviation from the 30-year average temperature during the dry days of April and May, the incidence of latent infection (only on leaves), and irrigation with microsprinklers or lowangled (12 degrees ) sprinklers were weak explanatory variables of panicle and shoot blight severity. Knowledge of panicle and shoot blight risk may contribute significantly to decisions regarding the appropriate application of fungicides, especially in years or fields of low risk. 相似文献
47.
Dysentery caused by Escherichia coli (S102-9) in calves: natural and experimental disease 总被引:10,自引:0,他引:10
G A Hall D J Reynolds N Chanter J H Morgan K R Parsons T G Debney A P Bland J C Bridger 《Veterinary pathology》1985,22(2):156-163
A dysentery syndrome was recognized among the Institute's calves at 18 to 21 days of age. It was reproduced experimentally in gnotobiotic calves with an atypical Escherichia coli (S102-9) isolated from the affected calves. In both natural and experimental disease the calves passed copious bright red blood in the feces and developed diarrhea. Walls of the colon and rectum were thickened, and the mucosa was reddened and covered by an exudate that contained mucus and blood clots. Bacteria were seen closely adherent to the luminal surfaces of enterocytes, often in cup-shaped depressions or on cytoplasmic pedestals. Microvilli were distorted, disorientated or absent. There was exfoliation of infected enterocytes and a mild acute inflammation of the underlying lamina. In two of five calves with natural disease, the adherent bacteria did not stain by the immunoperoxidase method with antisera raised against E. coli (S102-9). This indicated that there was possibly more than one bacterial cause of the syndrome. Lesions in experimentally infected calves were indistinguishable from those produced by some E. coli which are enteropathogenic for man, rabbits, and pigs. 相似文献
48.
ZS Perényi O Szenci PV Drion H Banga-Mboko NM Sousa B El Amiri JF Beckers 《Reproduction in domestic animals》2002,37(6):324-329
Pregnancy‐associated glycoproteins (PAGs) isolated from the placenta of various ruminant species are enzymatically inactive members of the aspartic proteinase family. The measurement of these proteins in the maternal blood can be a good indicator of the presence of a live embryo. As certain aspartic proteinases are present in biological fluids in physiological and pathological conditions at various concentrations, it was necessary to determine the specificity of three radioimmunoassay (RIA) systems currently used for the detection of PAG molecules. Commercially available members of the aspartic proteinase family like pepsinogen, pepsin, chymosin, rennet, cathepsin D and renin were tested in a wide concentration range (10 ng/ml – 1 mg/ml). Pepsinogen cross‐reacted in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 50 μg/ml and 500 μg/ml concentrations, respectively. In the presence of pepsin, cross‐reaction was observed in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 500 μg/ml and 1 mg/ml concentrations, respectively. Chymosin and rennet could cross‐react in RIA 2 and RIA 3, while renin and cathepsin D did not decrease the binding of the tracer to antisera more, than that of the minimal detection limit. As the plasma/serum concentrations of the examined aspartic proteinases reported in the literature were outside the concentration range where cross‐reaction was observed, it can be concluded that these RIA systems were specific for the detection of PAGs in biological fluids. 相似文献
49.
OBJECTIVE: To identify the risk factors for premature retirement because of tendon injury in a Thoroughbred racehorse population. ANIMALS: 175 Thoroughbred racehorses (cases) at the Hong Kong Jockey Club that were retired from racing because of tendon injury between 1997 and 2004 and for which the last preretirement exercise was at a fast pace were each matched with 3 control horses that were randomly selected from all uninjured horses that had galloped on the same date as that last exercise episode. PROCEDURES: Training data for all horses were examined. Conditional logistic regression analyses were performed to identify risk factors for retirement from racing attributable to tendon injury. Two multivariable conditional logistic regression models were created; each contained 8 explanatory variables. RESULTS: Compared with control horses, case horses were older at the time of import, accumulated more race distance soon after import, were more likely to have had previous official veterinary or ultrasonographic examinations, raced fewer times during their career, and were in training for a longer period and had exercised at a reduced intensity during the 180-day period preceding the last fast-paced work date. CONCLUSIONS AND CLINICAL RELEVANCE: In addition to identification of risk factors for tendon injury among racing Thoroughbreds, results have suggested that resources focused on obtaining accurate training data may be misdirected in the absence of internationally agreed criteria for incident tendon injury among racehorses. Nevertheless, changes in training intensity and findings of previous clinical examinations could be used to identify horses at risk of tendon injury-associated retirement. 相似文献
50.
Despite the phenomenon of heterosis having been used to improve crop productivity for almost a century, there is little understanding
of the molecular mechanisms involved. Heterosis has been described recently in the widely used plant model Arabidopsis thaliana. To assess the opportunity afforded by this system, we have developed, through pollination to a male sterile female parent
(Ler ms1), a range of hybrids of A. thaliana accessions. We tested this method of hybrid production in A. thaliana by comparing seed produced by natural pollination and hand pollination of emasculated plants. Our results demonstrate that
using male sterile lines, which more closely represent methods used for hybrid crop production, circumvents the problems associated
with the analysis of hybrids produced from emasculated plants. We identified hybrid combinations exhibiting mid-parent heterosis
for vegetative fresh weight ranging from −9 to 103% and characterised heterosis in the reciprocal hybrids of one strongly
heterotic combination. We found no evidence of a relationship between the extent of genetic relatedness of A. thaliana accessions and the strength of heterosis exhibited by their hybrids.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献