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911.
The vascular features of the distal epiphysis of the radius of 27 foals aged from 3 weeks premature to 120 days postpartum were determined. The limbs were perfused with barium, and the distal radius was sawn into sagittal slabs which were decalcified, cut into thin slices and radiographed. More arteries approached areas of thick cartilage than thin cartilage. In thick cartilage, vessels in a lattice network were observed, and adjacent to these vessels was sinusoidal filling in the epiphyseal subchondral bone, which had a similar pattern to sinusoidal filling in the metaphysis. The sinusoidal filling adjacent to thick cartilage was at the predisposition site for epiphyseal osteomyelitis lesions in foals. This particular type of bone infection occurs commonly in the foal, but much less commonly in other species. The vascular features of the immature epiphysis may account for the predominance of epiphyseal osteomyelitis in the foal. 相似文献
912.
The pharmacokinetics of thiamphenicol in lactating cows 总被引:2,自引:0,他引:2
N. Mestorino M. F. Landoni M. Alt J. O. Errecalde 《Veterinary research communications》1993,17(4):295-303
The pharmacokinetics of thiamphenicol were studied after intravenous and intramuscular administration of 25 mg/kg body weight in lactating cows. Distribution (t
1/2) and elimination (t
1/2) half-lives of 6.10±1.39 min and 1.60±0.30 h, respectively, were obtained after intravenous administration. The body clearance was 3.9±0.077 ml/kg per min and the apparent volume of distribution was 1220.79±256.67 ml/kg. The rate at which thiamphenicol appeared in the milk, as indicated by the penetration half-life (t
1/2P) (serum to quarters), was found to be 36.89±11.14 min. The equivalent elimination half-life (t
1/2E) (quarters to serum) from the milk was 3.62±1.06 h and the peak thiamphenicol concentration in the milk was 23.09±3.42 µg/ml at 2.5±0.32 h.After intramuscular injection, the elimination half-life was 2.2±0.40 h, the absorption half-life was 4.02±1.72 min and the peak concentration in the serum was 30.90±5.24 µg/ml at 23±8.4 min. The bioavailability after intramuscular administration approached 100%. The penetration half-life was 50.59±6.87 min, the elimination half-life was 5.91±4.97 h and the mean peak concentration in the milk was 17.37±2.20 µg/ml at 3.4±0.22 h.Abbreviations AUC
area under the concentration-time curve
- CAP
chloramphenicol
-
C
max
peak concentration
- IM
intramuscular
- IV
intravenous
- TAP
thiamphenicol
-
t
1/2
distribution half-life
-
t
1/2
elimination half-life
-
V
c
volume of central compartment
-
V
d
volume of distribution 相似文献
913.
F. van den Bosch 《European journal of plant pathology / European Foundation for Plant Pathology》1993,99(Z3):41-50
This paper deals with a study on the effects of mixtures of partially resistant cultivars in focus forming plant diseases.
The focus expansion velocity in a mixture of two partially resistant cultivars depends on four parameters, the focus expansion
velocity in a crop of cultivar 1 only and in a crop of cultivar 2 only, the net-reproduction in a crop of cultivar 1 and of
cultivar 2, respectively.
An explicit equation is developed for the damage of a cultivar mixture where the crop is infected by two physiological races
of the pathogen. It is shown that cultivar mixtures exist where damage is smaller than in crops of either of the two cultivars
only. A simple explicit formula is given on the basis of which it can be decided whether an optimal mixture exists for a given
pathosystem. 相似文献
914.
915.
916.
917.
918.
Summary The segregation of RFLP and RAPD markers was compared in two oilseed rape (Brassica napus L.) breeding populations from the cross Topas x R4, the latter being a low linolenic mutation line. A total progeny of 68 F2 and 40 microspore derived plants were studied with 25 markers. The results indicated a significant excess of Topas alleles at five RAPD loci in the microspore derived population. This suggests that genomic regions which probably affect microspore culture ability do not have identical distribution in the two population types. 相似文献
919.
920.