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SUMMARY

Original seedstocks, populations developed by recurrent selection, and inbred lines of two green curded cauliflowers, Di Macerata and Romanesco, were compared in two adjacent but independent trials at Wellesbourne. Trial results indicate that recurrent selection and inbreeding had generally led to significant improvement in uniformity of maturity, increased marketable yield, and improved quality characters contributing to overall appearance and marketability of the product. Depending on the strength of self incompatibility, inbred lines derived from improved populations could potentially be used as varieties, or as parental lines for hybrids.  相似文献   
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The toxicity of three second-generation rodenticides to Barn Owls (Tyto alba Scop.) has been investigated. Brodifacoum, difenacoum and flocoumafen were separately fed to owls over a period of 15 days via rodenticide-fed mice to simulate the potential route of exposure in the wild. The owls survived a cumulative dose of each rodenticide of at least 1.9 mg kg?1 owl body weight over 15 days. This is equivalent to the consumption of two 25 g mice with a rodenticide residue of 1 mg kg?1 each day for 15 days. Residue analysis confirmed that the liver is the organ which retains the largest residue of ingested rodenticide.  相似文献   
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The effect of drying conditions on harpagoside (HS) retention, as well as the use of near-infrared spectroscopy (NIRS) for rapid quantification of the iridoids, HS, and 8-rho-coumaroyl harpagide (8rhoCHG) and moisture, in dried Harpagophytum procumbens (devil's claw) root was investigated. HS retention was significantly (P < 0.05) lower in sun-dried samples as compared to tunnel-dried (60 degrees C, 30% relative humidity) and freeze-dried samples. The best retention of HS was obtained at 50 degrees C when evaluating tunnel drying at dry bulb temperatures of 40, 50, and 60 degrees C and 30% relative humidity. NIRS can effectively predict moisture content with a standard error of prediction (SEP) and correlation coefficient (r) of 0.24% and 0.99, respectively. The HS and 8rhoCHG NIRS calibration models established for both iridoid glucosides can be used for screening purposes to get a semiquantitative classification of devil's claw roots (for HS: SEP = 0.236%, r = 0.64; for 8rhoCHG: SEP = 0.048%, r = 0.73).  相似文献   
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Serum creatinine concentrations in retired racing Greyhounds   总被引:1,自引:1,他引:0  
Background: Greyhounds frequently have laboratory values that are outside reference intervals established for dogs. Our recognition of increased serum creatinine concentrations in several Greyhounds posed a problem when evaluating a Greyhound with suspected renal disease.
Objective: The purpose of this study was to compare serum creatinine concentrations between Greyhound and non-Greyhound dogs.
Methods: Thirty retired racing Greyhounds and 30 age-and gender-matched control non-Greyhound dogs were evaluated. Serum creatinine concentrations in both groups were measured using a standard biochemical method and compared statistically using a Kruskal-Wallis test.
Results: Creatinine concentration was significantly higher in the Greyhounds ( P < .01) than in the control group.
Conclusion: Greyhounds have a higher serum creatinine concentration than do non-Greyhound dogs. This idiosyncrasy should be taken into account when evaluating healthy Greyhounds and those with suspected renal disease.  相似文献   
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