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461.
In isoelectric focusing it is theoretically advantageous to use the highest voltages possible. Limitations are due to uneven heat evolution because of uneven conductivity of the individual carrier ampholyte molecules and/or insufficient cooling. The availability of a new carrier ampholyte. Pharmalyte, and a new flatbed apparatus with improved properties has made it possible to perform experiments at very high voltages. The results are discussed in terms of zone sharpness, resolution, and temperature profile. A method is proposed for accurate pI determinations, considering the temperature dependence of pI and the actual temperature in the gel. 相似文献
462.
Genetic and environmental variances were estimated for a number of characters in the annual plant Impatiens pallida by planting seed obtained through controlled crosses into their native field site or pots maintained in the greenhouse. Significant additive genetic variance was detected for three of 11 characters studied—germination date, cotyledon area, and date of first flower production. Significant dominance and/or maternal variance was found for seed weight, proportion of seeds germinating, cotyledon area, plant height, and number of leaves produced. Environmental variance was greater in the field compared with the greenhouse. Characters found to be under strong directional selection in a previous study showed no detectable additive genetic variance. While these populations exhibit conditions that in theory could contribute to the maintenance of genetic variation (limited pollen and seed dispersal distances and small-scale variation for edaphic characteristics influencing plant growth), levels of additive genetic variance for most characters were not significantly different from zero. 相似文献
463.
Maarit Hallikainen Essi Sarkkinen Ingmar Wester Matti Uusitupa 《BMC cardiovascular disorders》2002,2(1):14-7
Background
The short-term cholesterol-lowering efficacy of plant stanol esters has been open to debate, and the data from different clinical studies with hypercholesterolemic subjects are variable, partly due to lack of systematic studies. Therefore, we investigated the time in days needed to obtain the full cholesterol-lowering effect of stanol esters in hypercholesterolemic subjects. 相似文献464.