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The level of urine selenium in healthy adult population, 230 persons, was examined. Persons were selected regarding sex, ages, and smoking habits. No differences versus these observations have been found. For a total, group values are 16.96 Se nmol/creatinine mmol, SD=5.44. It is possible from a single-void specimen to express daily excretion of selenium. 相似文献
5.
Laid Douidah Lieven De Zutter Filip Van Nieuwerburgh Dieter Deforce Hanne Ingmer Olivier Vandenberg Anne-Marie Van den Abeele Kurt Houf 《PloS one》2014,9(1)
In this study, we report the screening of four Arcobacter species for the presence of small and large plasmids. Plasmids were present in 9.9% of the 273 examined strains. One Arcobacter cryaerophilus and four Arcobacter butzleri plasmids were selected for further sequencing. The size of three small plasmids isolated from A. butzleri and the one from A. cryaerophilus strains ranged between 4.8 and 5.1 kb, and the size of the large plasmid, isolated from A. butzleri, was 27.4 kbp. The G+C content of all plasmids ranged between 25.4% and 26.2%. A total of 95% of the large plasmid sequence represents coding information, which contrasts to the 20 to 30% for the small plasmids. Some of the open reading frames showed a high homology to putative conserved domains found in other related organisms, such as replication, mobilization and genes involved in type IV secretion system. The large plasmid carried 35 coding sequences, including seven genes in a contiguous region of 11.6 kbp that encodes an orthologous type IV secretion system found in the Wolinella succinogenes genome, Helicobacter pylori and Campylobacter jejuni plasmids, which makes this plasmid interesting for further exploration. 相似文献
6.
M. R. Sarić 《Plant and Soil》1987,99(1):197-209
Summary The paper discusses the problems of genetic aspects of plant mineral nutrition in the light of the results presented at the
First and Second Symposia on ‘Genetic Aspects of Plant Mineral Nutrition’ organized in Beograd in 1982 and Madison in 1985,
respectively. On the basis of the results, future directions of research are discussed. The papers deal with the concentration
and content of mineral nutrients in different genotypes, physiological and biochemical aspects of the genetic specificity
of plant mineral nutrition, relations between plant genotypes and nitrogen fixing micro-organism strains, as well as with
some related problems which have been investigated to a lesser extent. Particular attention is paid to papers and problems
referring to genetic and breeding research work linked with genetic aspects of plant mineral nutrition as well as the possibilities
of developing new cultivars requiring certain soil and mineral nutrition conditions for their cultivation. 相似文献
7.
Densities of Drosera intermedia were low in two studied habitats (10–25 ramets m−1 ), a path through a wet heath (short inundation in spring, low soil moisture in summer) and a pool edge (longlasting inundation, high soil moisture in summer). The low densities could be explained by the observed low recruitment and high adult mortality.
The low recruitment resulted from: (1) a high first year mortality of the large number of seedlings that emerged each year in the path population, caused by summer drought and cover with algae after heavy rainfall; (2) the absence in two years out of three of seedling emergence at the pool edge, due to the longlasting inundation. In neither population any seedlings survived to flower; (3) low vegetative reproduction rate.
Adult mortality during the growing season was caused by drought, which did not occur at the pool edge. Rapid senescence in autumn, caused by summer drought on the path and by a rapid submersion after heavy rainfall at the pool edge, was associated with a high winter mortality. 相似文献
The low recruitment resulted from: (1) a high first year mortality of the large number of seedlings that emerged each year in the path population, caused by summer drought and cover with algae after heavy rainfall; (2) the absence in two years out of three of seedling emergence at the pool edge, due to the longlasting inundation. In neither population any seedlings survived to flower; (3) low vegetative reproduction rate.
Adult mortality during the growing season was caused by drought, which did not occur at the pool edge. Rapid senescence in autumn, caused by summer drought on the path and by a rapid submersion after heavy rainfall at the pool edge, was associated with a high winter mortality. 相似文献
8.
Summary Electron-microscopic immunocytochemistry for the demonstration of CCK-like material in basal endocrine cells of the midgut of Aeschna cyanea, Locusta migratoria, Carausius morosus and Periplaneta americana was performed by use of the peroxidase-antiperoxidase procedure and the colloidal gold method. Immunoreactive cells appeared scattered among digestive and regenerative cells of the epithelium. Immunoreactivity was specifically detected over round to oval electron-dense granules whose size appeared rather different from species to species. Thus, the average size of 30% (d30) of the largest granules ranged from 312 nm in Periplaneta americana to 159 nm in Carausius morosus with intermediate values in Aeschna cyanea (d30=195 nm) and Locusta migratoria (d30=225 nm). 相似文献
9.
In the lichen genusUsnea different species ofTrebouxia-phycobionts as well as different haustorial types are known. The isolated and cultivated phycobiont ofUsnea longissima
Ach. was studied by light- and electron microscopy and resembles in cytomorphological details the type ofTrebouxia impressa
Ahmad. In addition to simple wall-to-wall contacts between the symbiotic components also intraparietal (=intrawall-)haustoria could be observed as the normal interaction type.
Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet. 相似文献
10.
S. Živanović 《Human Evolution》1988,3(5):329-334
Studies of the morphological features of the temporal region of mesolithic skulls from Padina in the Iron Gate Gorge of the
Danube revealed a very prominent and large supramastoid ridge which is the most striking feature in skulls of both sexes.
Mastoid processes were larger in male skulls, but in 25% of the cases there was an overlap between the size of the processes
in male and female specimens. The mastoid ridge was prominent in both sexes. The digastric fossa was always well defined in
both sexes and in the two thirds of the skull specimens it was deep. The posterior root of the zygoma was prominent in all
the skulls, but it was better developed in the male specimens. The parietotemporal suture in both sexes rises above the level
of the pterion. There were no morphological or anthropometrical differences between the left and the right side of individual
skulls outside the limits of natural asymmetry. All these morphological characteristics of the temporal region may help in
racial and sexual diagnosis of the Mesolithic skulls from the Iron Gate Gorge. 相似文献