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Heidi Weberru? Raphael Pirzer Robert Dalla Pozza Heinrich Netz Renate Oberhoffer 《PloS one》2016,11(3)
Carotid intima-media thickness (cIMT) is a surrogate marker of early atherosclerotic changes in children. cIMT-studies are hard to compare, due to variations in ultrasound protocols, especially regarding the common carotid artery (CCA) segment measured in relation to the bulb. This study’s purpose was therefore to compare two distinct CCA segments in children, to see if cIMT values differ substantially according to the site of measurement. cIMT was assessed after power calculation in 30 children (15 girls) aged 8–17, using B-Mode ultrasound (5–13 MHz) at two CCA locations. The first measurement was performed over a distance of 1 cm immediately after the bulb (A), the second 1cm proximal the bulb (B) over the same distance of 1cm length. Means of end-diastolic far wall cIMT were compared between measurement A and B. cIMT in 30 participants was 0.51±0.06 mm for measurement A and 0.51±0.05 mm for measurement B. Results did not differ significantly (p = .947) over a distance of 2 cm after the bulb. According to our results, studies measuring CCA IMT within the first 2 cm, either close to the bulb or further proximal, can be compared. This will improve interpretation of data and application of reference values. 相似文献
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Raphael Chijioke Njoku 《Dialectical Anthropology》2007,31(1-3):45-64
It is difficult to completely understand the life history of an intellectual excluding an understanding of his family upbringing
and formative years. Family upbringing and childhood environment, often the less known part of a life history, play crucial
roles in shaping the ideas and values individuals espouse in their adult life. Notwithstanding, this paper is not concerned
with Don C. Ohadike’s childhood. It rather focuses on the professional career of our able historian – that is the part of
his life as revealed by his most outstanding published writings. Ohadike’s published works contain a wellspring of idioms
that tell much about his values, quality of mind, and his mission as an African historian. Ohadike was a humanist, an African
patriot, and a nationalist crusader. His entire philosophy centered on safeguarding his African identity in an emergent world
of cultural imperialism.
The funds for this research were provided by a NEH-funded fellowship at the Schomburg Center, New York in the Spring of 2007.
I owe a lot of gratitude to Professor John McLeod and Dean Blaine Hudson for granting me the extra incentives to pursue my
research in New York. While all errors and misinterpretations are mine, I wish to thank the editors and anonymous reviewers
for Journal of Dialectical Anthropology for their perspective comments and suggestions on earlier drafts of this paper. 相似文献
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Spectrophotometric assay for ornithine decarboxylase 总被引:11,自引:0,他引:11
That T. Ngo Kurt L. Brillhart Rowland H. Davis Raphael C. Wong Jack H. Bovaird Joseph J. Digangi Janet L. Ristow J. Lawrence Marsh Andrew P. H. Phan Howard M. Lenhoff 《Analytical biochemistry》1987,160(2):290-293
A rapid and sensitive spectrophotometric assay for ornithine decarboxylase is described. It is based on the observation that the product of ornithine decarboxylase, putrescine, reacts with 2,4,6-trinitrobenzenesulfonic acid to give a colored product soluble in 1-pentanol whereas ornithine does not. The amount of putrescine produced by the enzyme was determined by measuring the absorbance of the 1-pentanol extract of the reaction mixture at 420 nm, and by comparing the results to those obtained by the trapping of 14CO2 and by HPLC assays. The three assays were found to be equivalent in sensitivity, with the spectrophotometric assay having the advantages of being relatively rapid, requiring only common laboratory equipment, and not requiring the use of radioactive isotopes. 相似文献
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Mendel's work in hybridization is ipso facto a study in inheritance. He is explicit in his interest to formulate universal generalizations, and at least in the case of the independent segregation of traits, he formulated his conclusions in the form of a law. Mendel did not discern, however, the inheritance of traits from that of the potential for traits. Choosing to study discrete non-overlapping traits, this did not hamper his efforts. 相似文献
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Hans Fricke Karen Hissmann Jürgen Schauer Olaf Reinicke Lutz Kasang Raphael Plante 《Environmental Biology of Fishes》1991,32(1-4):287-300
Synopsis In 1987 and 1989 coelacanths were observed for the first time in their natural habitat with the help of submersibles. Coelacanths were found between 150–253 m depth, their preferential depth seems to be around 200 m; the water temperature ranged between 16.5–22.8° C. During the day coelacanths aggregate in small non-aggressive groups in sheltered lava-caves. Caves might be a limiting factor for distribution. At night they leave the caves for hunting by drifting singly along the steep lava slopes. They migrate between different caves located within a large home range covering more than 8 km coastline. Coelacanths are site-attached, some for a period of at least 2 years. Our own observations and earlier catch records show that only the west coast of Grand Comoro is a suitable coelacanth habitat with more structural complexity and prey fish abundance than other coastlines of the island. From our survey we estimated a total coelacanth population off Grand Comoro to be 150–210 individuals; a saturated population would be 370–510 individuals. This small relict population seems to be stable. International protection of coelacanths against commercial interests is needed 相似文献