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61.
Soaking sugar-beet seed in 1.0 M sodium chloride solution killed6 per cent of the seeds but the remainder germinated when transferredto more dilute (< 0.28 M) solutions. Small differences inthe concentration of dilute sodium chloride did not change thenumber of seeds which germinated but greatly affected wateruptake and seedling growth. For example, after 10 days at 15?C, radical length decreased almost linearly from 50 to 5 mmwhen the concentration increased from 0 to 0.2 M. Presoakingseed in water increased the concentration tolerated withoutreduction in growth. Advancing seed (presoaking followed byairdrying) increased seedling yield by 70 per cent by decreasingthe time taken to emerge, increasing the number of seeds whichgerminated and eliminating the detrimental effects of smallamounts of sodium chloride. Advancing seed also marginally reducedthe variation in seedling yield in laboratory and controlledenvironment experiments. To minimize the risk of killing seedsor decreasing seedling growth it seems that no more than therecommended quantity (377 kg ha1) of sodium chlorideshould be applied to sugar-beet crops. 相似文献
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Pain, and nausea and vomiting are the two cardinal symptoms of acute pancreatitis. There are variations in the combinations of symptoms that appear in patients who have acute pancreatitis, but in most cases the combination fits one or another of five classifications. Blood amylase and urinary diastase determinations are valuable aids in the diagnosis of acute pancreatitis. These findings must be correlated with the stage of the disease. As the disease may be treated successfully (by means outlined) without surgical intervention, clinical diagnosis is important. Cholecystograms after an attack of acute pancreatitis, although advisable, should not be made too soon after subsidence, because of the danger of exacerbation. 相似文献
64.
Immunologic studies on persons residing in a plague endemic area 总被引:1,自引:0,他引:1
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N. CARTER J. C. ENTWISTLE † A. F. G. DIXON J. M. PAYNE 《The Annals of applied biology》1989,115(1):31-37
Aphid counts and yield results from a three-year field trial of the effectiveness of insecticides applied at various growth stages of winter wheat, were used to test the accuracy of the predictions of the Entwistle and Dixon (1986, 1987) models for forecasting aphid damage and population growth. In general, the peak aphid populations of Sitobion avenae and damage were not accurately predicted but the spray recommendations, which would have resulted from the predictions, would have been correct in each of the three years; one outbreak and two non-outbreak years. In particular the effectiveness of early spraying was over-estimated because the persistence of the effect of insecticides was over-estimated. It is recommended that further work be done on the rate of development of aphid populations following application of insecticides. 相似文献
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MOTIVATION: Recently, we described a Maximum Weighted Matching (MWM) method
for RNA structure prediction. The MWM method is capable of detecting
pseudoknots and other tertiary base-pairing interactions in a
computationally efficient manner (Cary and Stormo, Proceedings of the Third
International Conference on Intelligent Systems for Molecular Biology, pp.
75-80, 1995). Here we report on the results of our efforts to improve the
MWM method's predictive accuracy, and show how the method can be extended
to detect base interactions formerly inaccessible to automated RNA modeling
techniques. RESULTS: Improved performance in MWM structure prediction was
achieved in two ways. First, new ways of calculating base pair likelihoods
have been developed. These allow experimental data and combined statistical
and thermodynamic information to be used by the program. Second, accuracy
was improved by developing techniques for filtering out spurious base pairs
predicted by the MWM program. We also demonstrate here a means by which the
MWM folding method may be used to detect the presence of base triples in
RNAs. AVAILABILITY: http://www.cshl.org/mzhanglab/tabaska/j axpage. html
CONTACT: tabaska@cshl.org
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