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The aim of the study was to compare apparent Zn absorption and Zn status of weanling rats fed diets that differed in Zn level, fat level and fat source. Semi‐synthetic diets, which were about isoenergetic and contained 3% soyabean oil, were supplemented with 7 or 100 mg Zn/kg to create a mild Zn deficiency (LZ) or a high Zn supply (HZ) and with 0 (LF), 22% beef tallow (BT) or 22% sunflower oil (SF) according to a 2 × 3 factorial design of treatments. They were fed ad libitum to 6 × 8 rats for 28 days. Energy intake and growth rates were comparable among the HZ groups. Weight gains in the LZ‐LF, LZ‐BT and LZ‐SF groups averaged 5.54, 4.95 and 4.15 g/day, and apparent Zn absorption averaged 79.4, 60.3 and 48.0 μg Zn/day, respectively, whereas faecal Zn excretion was comparable among these groups. Apparent Zn absorption, and plasma and femur Zn concentrations were lower in the high‐fat groups than in the LF group, possibly due to the high cellulose content of the BT and SF diets. Plasma Zn concentrations were higher in the animals fed the BT‐based than in the SF‐based diets, whereas femur and soft tissue Zn concentrations were comparable among these groups. The differences between the LZ‐BT and LZ‐SF groups in growth rate, Zn absorption rate and Zn status were confirmed in a second experiment. The results indicate that moderately Zn‐deficient diets enriched with SF in relation to BT affect Zn metabolism of weanling rats by a yet unknown mechanism.  相似文献   
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Objective : The purpose of this study was to investigate whether implantable loop recorders could be used in the diagnosis of unexplained collapse in dogs. Methods : The medical records of six dogs presented to the University of Liverpool Small Animal Teaching Hospital between May 2003 and October 2006 for further evaluation of intermittent syncopal episodes, collapse or episodic weakness, were reviewed. All these dogs underwent standard investigations and had implantable loop recorders placed. Results : A provisional diagnosis of supraventricular tachycardia was made in one dog, and diagnoses of exclusion of arrhythmogenic right ventricular cardiomyopathy and idiopathic epilepsy was made in two dogs. One dog suffered no further syncopal episodes, a diagnosis was not reached in another dog and the final dog was lost to follow‐up. Clinical Significance : The implantable loop recorder can be used successfully for the diagnosis of unexplained collapse in dogs.  相似文献   
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The genetic relationship among individuals at one locus is characterized by nine coefficients of identity. The coefficients of inbreeding, coancestry and dominance (or fraternity) are just linear functions of them. Here, it is shown how they can be estimated using biallelic and triallelic markers using the method of moments, and comparisons are made with other methods based on molecular coancestry or molecular covariance. It is concluded that in the general case of dominance and inbreeding with biallelic markers, only the coefficients of inbreeding and coancestry can be estimated, but neither the single coefficients of identity nor the coefficient of dominance can be estimated. More than two alleles are required for a full estimation as illustrated with the triallelic situation.  相似文献   
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Venous air embolism was suspected in 3 hospitalised horses on the basis of an inadvertently open jugular venous line. Subsequently the 3 horses developed clinical signs including cardiovascular collapse, cardiac dysrhythmia, pulmonary oedema, behavioural abnormalities and neurological signs consistent with central nervous system injury. Treatment included intranasal oxygen therapy, i.v. fluid administration and anti‐inflammatory therapy. Specific therapy aimed at treating air embolism in man is reviewed, with pertinent therapy potentially applicable to horses emphasised.  相似文献   
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