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11.
Objective The mechanical properties of three materials (No. 2 polypropylene, No. 5 polybutilate-coated multifilament polyester and 18, 27 and 36 kg test monofilament nylon leader material) commonly used for extra-capsular stabilisation of the stifle in dogs with cranial cruciate ligament insufficiency were determined. The ability of No. 5 polybutilate-coated multifilament polyester and 36 kg test monofilament nylon leader material, when placed as extra-capsular sutures, to mitigate cranial drawer was evaluated in hindlimbs of cadavers. Design An in vitro mechanical study. Animals Seven pairs of hindlimbs harvested from adult greyhound dogs recently euthanased for other reasons. Procedure Samples of each material, including samples of 27 kg test leader material that had been sterilised by one of three methods (ethylene oxide, one or five cycles in an autoclave), were loaded to determine tensile and stress relaxation properties. The effect of cyclic loading on a No. 5 polybutilate-coated multifilament polyester and 36 kg test leader material was also determined. Using the harvested hindlimbs, cranial drawer was measured before and after transection of the cranial cruciate ligament and on the first and twelfth cycle following extra-capsular stabilisation with either No. 5 polybu-tilate-coated multifilament suture or 36 kg test leader material. Results Leader material was found to have the most suitable mechanical characteristics for use as extracapsular stabilisation of the cranial cruciate ligament deficient stifle. Of the sterilisation methods, ethylene oxide was found to have the least detrimental effects on the handling and material characteristics of the leader material. Stifles stabilised with 36 kg test leader material had significantly less drawer than those stabilised with No. 5 polybutilate-coated multifilament polyester suture. Clinical implications Monofilament nylon leader material would appear to have suitable mechanical properties for extra-capsular stabilisation of the cranial cruciate ligament deficient stifle. If possible the material should be sterilised using ethylene oxide.  相似文献   
12.
Supplemental fats (SF) have special value in the diets of dairy cows with superior productive ability, because the high energy density of SF allows greater energy consumption and direct transfer of the fatty acids (FA) of the SF to milk fat; this increases metabolic efficiency. Some SF, especially oils with a high degree of unsaturation, disturb ruminal fermentation, decrease fiber digestibility, and lower milk fat test; however, oilseeds (e.g., whole cottonseed) can be fed without observable ruminal inhibition, probably because of a slow release of the oil into ruminal contents. A number of commercial fat supplements are available that have little effect on ruminal fermentation and are highly digestible postruminally. A product of the calcium salts of palm oil fatty acids was shown to have a NE for lactation of more than three times that of corn. As the emphasis in milk pricing formula changes from milk fat to milk protein, there is greater concern regarding the propensity of fat supplements to decrease milk protein (casein) percentage. In two studies, a supplement of ruminally protected lysine and methionine largely prevented the reduction in casein percentage that occurred with feeding SF, indicating that the amino acid profile of undegraded dietary protein is important with regard to preventing the lower casein percentage. Combining fat supplements that are slowly released in the rumen with those that are inert in the rumen will allow maximal use of SF.  相似文献   
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14.
Nasopharyngeal cryptococcosis   总被引:1,自引:0,他引:1  
Naturally occurring cryptococcosis in five cats, a dog and a koala is described. Involvement of the nasopharynx was documented in all patients, and nasopharyngeal mass lesions accounted for the major presenting complaints in four. Signs referable to nasopharyngeal disease included snoring, stertor, inspiratory dyspnoea and aerophagia. Diagnoses were made by caudal rhinoscopy using a retroverted flexible endoscope, vigorous orthograde flushing with saline, or at necropsy. Concurrent cryptococcal rhinitis was present in all cases, although involvement appeared limited to the caudal nasal cavity in most cases. Typical signs of nasal cavity disease, such as sneezing and nasal discharge, were often absent. Treatment of nasopharyngeal cryptococcosis should include physical dislodgement or debulking of lesion(s) to provide immediate alleviation of upper airway obstruction, followed by systemic antifungal therapy to eliminate residual infection from the nasal cavity. Infections caused by Cryptococcus neoformans var gattii accounted for a disproportionately large number of these cases.  相似文献   
15.
The performance of amorphous organic photorefractive (PR) materials in applications such as optical data storage is generally limited by the concentration of active molecules (chromophores) that can be incorporated into the host without forming a crystalline material with poor optical quality. In polymeric PR systems described previously, performance has been limited by the necessity of devoting a large fraction of the material to inert polymer and plasticizing components in order to ensure compositional stability. A new class of organic PR materials composed of multifunctional glass-forming organic chromophores is described that have long-term stability and greatly improved PR properties.  相似文献   
16.
Models predict that food-web structure is regulated by both consumers and resources, and the strength of this control is dependent on trophic position and food-web length. To test these hypotheses, a meta-analysis was conducted of 11 fish (consumer)-by-nutrient (resource) factorial plankton community experiments. As predicted, zooplankton biomass was under strong consumer control but was weakly stimulated by nutrient additions; phytoplankton biomass was under strong resource control with moderate control by fish. However, the phytoplankton and zooplankton responses to nutrient additions did not follow theoretical predictions based on the number of trophic levels in the food web.  相似文献   
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18.
M Kotiw  C R Wilks  J T May 《Avian diseases》1982,26(4):718-731
Strains of infectious laryngotracheitis virus (ILTV) were examined using an indirect immunofluorescent test (IIF) and with restriction endonucleases for detecting intratypic differences. Electrophoretic analysis of ILTV DNA fragments cleaved with restriction endonuclease Hind 111 clearly distinguished between strains. The IIF test did not discriminate between strains. A molecular weight estimate of ILTV DNA was made by summation of restriction endonuclease fragments cleaved with BamH1 (102.1 X 10(6)) and Hind111 (97.35 X 10(6)). Differences between the estimates may indicate the presence of submolar fragments.  相似文献   
19.
SUMMARY A haemodynamically significant ventricular septal defect was diagnosed in a 3-month-old male Cavalier King Charles Spaniel. A median sternotomy was performed and the 6.5 kg dog placed on cardiopulmonary bypass using pump-assisted cross-circulation. A 10 mm diameter peri-membranous ventricular septal defect was closed using a continuous suture of 4–0 polypropylene, via a 2.5 cm incision in the right ventricular outflow tract. The duration of cardiopulmonary bypass was 90 minutes. Complications in the immediate postoperative period were mild and easily managed.  相似文献   
20.
A total of 1,355 random samples taken from bovine serums submitted for brucellosis testing in Victoria were submitted to the microscopic agglutination test for the presence of antibody to 12 serovars of Leptospira interrogans . The most common reaction obtained was to serovar hardjo , although the percentage of reactors varied from 24.8% in the metropolitan area to 56.3% in north-eastern Victoria (mean 40.6%). A total of 86.3% of farms from which 3 or more samples were taken had at least one reactor to serovar hardjo . The prevalence of antibody to other serovars was tarassovi (7.8% of reactors), ballum (3.7%), pomona (2.4%), autumnalis (1.8%) and bataviae (1.2%). Reactions to other serovars were observed in serums of less than 1% of cattle tested; serums from 50.8% of cattle did not react to any antigen.  相似文献   
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