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1.
L Reeve-Johnson 《The Veterinary record》2001,149(18):549-552
Respiratory disease was induced in 16 calves, and the terminal clinical signs of disease and postmortem pathological observations were recorded. By Spearman's correlation coefficient, the respiratory rate, rectal temperature and clinical scores of the calves were significantly correlated with the extent of lung consolidation. The respiratory rate was the clinical sign most consistently correlated with the other clinical and pathological signs of respiratory disease. 相似文献
2.
Chloroform-methanol (2:1 v/v), absolute methanol, and 90% acetone were evaluated for their effectiveness as extractants of chlorophyll a from samples of phytoplankton communities collected from catfish ponds. Chloroform-methanol consistently extracted more chlorophyll a than either 90% acetone or methanol. Precision for the methanol extraction was also unacceptably low, with an average coefficient of variation of 17%. Average coefficients of variation for the chloroform-methanol and 90% acetone extraction procedures were 6 and 5%, respectively. Filtered samples should be steeped in chloroform-methanol for at least 4 h to obtain maximum chlorophyll extraction, and the addition of MgCO3 to the extractant as a buffer is not necessary. 相似文献
3.
Michael R. Metcalf DVM MS Lloyd P. Tate DVM Loouis C. Sellett MS 《Veterinary radiology & ultrasound》1989,30(2):80-87
4.
The stratum corneum measured on fresh frozen sections was found to be considerably thicker than previously reported. It was uniformly permeated with sebum, which also formed an intact film over the skin surface and it could readily be divided into two zones. The living epidermis was approximately half as thick as the stratum corneum. 相似文献
5.
This paper describes three experiments aimed at determining the proportion of dead birds at sea which come ashore and are found by members of the public, and discusses the results in relation to wind velocities. From 11% to 58% of the ringed (Larus spp.) corpses thrown into the Irish Sea between Liverpool and the Isle of Man on three occassions in 1973 and early 1974 were recovered. There were large differences between experiments in the timing of the recoveries, although half usually occurred within 11–14 days of dropping. The resultant wind velocities during the time the first bodies recovered from each experiment were at sea were calculated. Comparison of the observed and expected tracks of these bodies confirmed that the wind was the main factor influencing the direction of drift. Gull corpses drifted at a minimum of 2·55±0·93% of the wind speed, although there was much variation and some travelled at over 4% windspeed. With a few exceptions, the observed distribution of recoveries could be broadley predicted by wind vector analysis. The amount of onshore wind when the bodies had reached coastal waters was not related to the subsequent recovery rates. Further experiments are necessary if some of our findings are to be explained and examination of the effect of tidal cycles on the beaching of corpses would also be of value. 相似文献
6.
When perennial ryegrass and wild white clover are grown in a phosphorus-deficient soil, there is a difference in the extent to which they use the added phosphorus, especially when the phosphorus supply (potential) is small. In these circumstances the clover makes the better use of the phosphorus. The similarity of the Larsen values obtained with these two species, however, indicates that this must be largely due to the species absorbing the phosphorus at different rates, and not to any interspecific difference in ability to utilize the supply. Both perennial ryegrass and cocksfoot gave higher L values for the hay than for the pasture variety, indicating that slowly-exchangeable phosphorus might be more accessible to the former than the latter. Perennial ryegrass, cocksfoot, timothy, wild white clover and red clover showed minimum values for L at varying times after sowing which were characteristic of the species. This is explained in terms of the isotopic exchange reactions taking place. 相似文献
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10.
Byron CR Orth MW Venta PJ Lloyd JW Caron JP 《American journal of veterinary research》2003,64(6):666-671
OBJECTIVE: To characterize potential mechanisms of action of glucosamine inhibition of matrix metalloproteinase (MMP) expression and activity in lipopolysaccharide (LPS)-stimulated equine chondrocytes. SAMPLE POPULATION: Chondrocytes cultured from samples of metacarpophalangeal articular cartilage collected from cadaveric limbs of horses. PROCEDURE: The effect of glucosamine on MMP activity in conditioned medium from LPS-stimulated cartilage explants was determined by a colorimetric assay with azocoll substrate. Treatments consisted of negative and positive controls, glucose (50 mM), and glucosamine (50, 25, 6.25, 3, and 1.5 mM). The influence of glucosamine on MMP synthesis was determined in chondrocytes in pellet culture incubated with LPS (20 microg/mL). Concentration of MMP-13 was quantified in spent medium via ELISA; nonspecific MMP activity was determined via azocoll digestion in organomercurial-activated medium. Effects of glucosamine on MMP mRNA concentration in similarly treated chondrocytes were determined by northern blot hybridization with MMP-1, -3, and -13 probes. Statistical analyses were performed with 2-way ANOVA. RESULTS: Glucosamine had no effect on activated MMP activity but inhibited MMP protein expression, as determined by azocoll digestion (glucosamine, 3 to 50 mM) and MMP-13 ELISA (glucosamine, 1.5 to 50 mM). Resting mRNA concentrations for MMP-1, -3, and -13 mRNA were significantly lower in cultures exposed to glucosamine at concentrations of 50 and 25 mM than those of positive controls. CONCLUSIONS AND CLINICAL RELEVANCE: Glucosamine appears capable of pretranslational, and possibly also translational, regulation of MMP expression; data suggest a potential mechanism of action for chondroprotective effects of this aminomonosaccharide. 相似文献