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511.
512.
Fabio L. Urbina Shalini Menon Dennis Goldfarb Reginald Edwards M. Ben Major Patrick Brennwald Stephanie L. Gupton 《Cell reports》2021,34(6):108743
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513.
Lucile L. Adams-Campbell Reginald L. Periston Kyung Sook Kim Ernest Mensah 《Obesity (Silver Spring, Md.)》1995,3(3):215-219
There are limited data available concerning the influence of obesity, a major cardiovascular disease risk factor, in relationship to coronary artery disease (CAD). This is of considerable importance to African-Americans since African-Americans have one of the world's highest CAD mortality rates coupled with the fact that obesity is extremely prevalent in this population. The present study assessed the relationship between body mass index and CAD in African-Americans undergoing coronary angiography. Eight hundred sixty-six available cardiac catheterization reports between the years 1983 through 1990 were retrospectively reviewed at Howard University Hospital in Washington, D.C. CAD was prevalent in 59.6% and 41.2%, males and females, respectively. Among the males overweight and obesity were found in 22.4% and 20.9%, respectively, compared to 39.6% and 30.6% for females. An upside-down U-shaped relationship between BMI and CAD was found. The interpretation of this finding is that being overweight is associated with increased risk of CAD compared to the lean and obese. 相似文献
514.
Gabriel D. McNett Ronald N. Miles Dorel Homentcovschi Reginald B. Cocroft 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2006,192(12):1245-1251
Conventional approaches to measuring animal vibrational signals on plant stems use a single transducer to measure the amplitude
of vibrations. Such an approach, however, will often underestimate the amplitude of bending waves traveling along the stem.
This occurs because vibration transducers are maximally sensitive along a single axis, which may not correspond to the major
axis of stem motion. Furthermore, stem motion may be more complex than that of a bending wave propagating along a single axis,
and such motion cannot be described using a single transducer. Here, we describe a method for characterizing stem motion in
two dimensions by processing the signals from two orthogonally positioned transducers. Viewed relative to a cross-sectional
plane, a point on the stem surface moves in an ellipse at any one frequency, with the ellipse’s major axis corresponding to
the maximum amplitude of vibration. The method outlined here measures the ellipse’s major and minor axes, and its angle of
rotation relative to one of the transducers. We illustrate this method with measurements of stem motion during insect vibrational
communication. It is likely the two-dimensional nature of stem motion is relevant to insect vibration perception, making this
method a promising avenue for studies of plant-borne transmission.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
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516.
Soybeans displaying incomplete dominance for leaf pigmentation possess chloroplasts with characteristic shape and organization of photosynthetic membranes. The chloroplasts of light green plants lack grana typical of dark green or a field type (Beeson) but normally possess doubled thylakoids. Achlorophyllous lethal yellow plants have thylakoids reduced to single spiralled membranes. The yellow plants lack a waxy cuticle over the leaf surface which is characteristic of all other soybeans examined, and they lack catalase activity in microbodies. Photosynthetic rates in the light green plants are at least as high as in the fully pigmented ones and photorespiration levels are not significantly different. Thus, in light green plants greater efficiency of enzymatic processes in photosynthesis apparently offsets the inhibitory activities associated with photorespiration. Single allele alterations from dark green to light green and light green to lethal yellow appear to alter a variety of structures and functions. 相似文献
517.
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers U04227-U04232 相似文献
518.
Detection ofLegionella pneumophila by serogroup-specific fluorescent antibodies was combined with a tetrazolium dye (INT) to measure electron transport activity. The biological uptake and reduction of the INT dye was studied in pure cultures and in natural water samples with respect to temperature. Uptake was complete within 60 min. Controls inhibited with formaldehyde demonstrated little activity. Both the in vitro and in situ determinations suggested that the electron transport system ofLegionella was active over a temperature range of 25 to 60°C. 相似文献
519.
Reginald C. Agu 《Process Biochemistry》1995,30(8):763-766
The effect of various concentrations of potassium bromate (a malting additive) was studied on malting sorghum. Potassium bromate at concentrations of 50-125 mg/litre sprinkled on germinating sorghum (28°C ± 1°C) at steep out increased the filtration rate and cold and hot extract values after four days of germination. There was no significant decrease in malting loss at the low concentrations (50-125 mg/litre) of the additive. A higher dose, of 150 mg/litre, decreased the malting loss, while at a concentration of 125 mg/litre a significant increase was observed for the diastatic power after four days of germination. 相似文献