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Mortality rates among White Leghorn-Rhode Island Red pure-line and reciprocal cross adult female progeny were recorded for 8 years. The mortality rate among progeny of White Leghorn males exceeded that of the progeny of Rhode Island Red males in both pure-line and crossbreds. White Leghorn X Rhode Island Red crossbred progeny had the highest mortality rate. In a second phase of the study, a comparison was made between mortality rates of male and female progeny of White Leghorn-Rhode Island Red reciprocal crosses. Rate of loss was significantly lower in males than in females but did not differ between crosses. These results support a conclusion that sex linkage is a major factor in differential mortality rates between progeny of White Longhorn-heavy breed reciprocal crosses. 相似文献
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DP Stoker ML Perl G Abrams AR Baden T Barklow BA Barnett AM Boyarski J Boyer PR Burchat F Butler JM Dorfan GJ Feldman G Gidal G Hanson BD Harral K Hayes D Herrup JE Hylen WR Innes JA Jaros JA Kadyk D Karlen SR Klein AJ Lankford BW LeClaire M Levi V Lüth JA Matthews RA Ong K Riles PC Rowson DR Wood 《Canadian Metallurgical Quarterly》1989,39(7):1811-1824
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Biomechanical analysis using nondestructive and destructive investigative methods was performed to evaluate the mechanisms of cervical compression injuries. These injuries produce two basic modes of failure: 1) anterior dislocation; and 2) rupture of the anterior ligamentous complex of the vertebral body. Distribution of these two failure patterns was determined by the initial cervical spine position; translational alignment did not have a significant effect. Different results were observed between spines positioned in flexion and extension, indicating that the most important factor determining the mode of failure was rotational alignment in the sagittal plane. 相似文献
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The increased incidence of drowsiness in hypoalbuminemic patients administered diazepam and more rapid clearance of tolbutamide in cirrhotics may be due to changes in plasma protein binding. The binding of diazepam and tolbutamide was studied by equilibrium dialysis at 37degreesC over a total drug concentration range of 1 to 10 mug/ml and 50 to 300 mug/ml, respectively, in plasma from 21 normal and 14 alcoholic subjects. At 1 mug/ml, diazepam plasma protein binding (+/- S.D.) was 98.5+/-0.4 per cent in normals and 97.8+/-1.2 per cent in alcoholics; at 100 mug/ml, tolbutamide binding was 97.8+/-0.3 per cent in normals and 95.1+/-4.2 per cent in alcoholics. For both agents at all concentrations, the binding to plasma from alcoholics was significantly decreased (P less than 0.01-less than 0.02). The extent of binding of both drugs was dependent on the albumin concentration. These findings suggest that important changes in pharmacologic effect, distribution, and clearance of diazepam and tolbutamide can be anticipated in alcoholics with hypoalbuminemia. 相似文献
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