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1.
2.
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
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4.
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
5.
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
6.
Detection of P-glycoprotein on endothelial and endocrine cells of the human pancreatic islets by C 494 monoclonal antibody 总被引:1,自引:0,他引:1
D. Bani M. L. Brandi C. A. Axiotis T. Bani-Sacchi 《Histochemistry and cell biology》1992,98(4):207-209
Summary P-glycoprotein, an integral membrane protein acting as an energy-dependent efflux pump, has been detected immunocytochemically in the human pancreatic islets using C 494 monoclonal antibody. Intense P-glycoprotein immunoreactivity was found in both endothelial cells of islet blood capillaries and in endocrine cells. Strong expression of P-glycoprotein has been found in the capillary blood vessels at blood-tissue barrier sites and in numerous kinds of cells with secretory/excretory function. Therefore the present findings suggest that P-glycoprotein may play a role in controlling the composition of the extracellular fluids and the intracellular milieu of endocrine islet cells and possibly in regulating their secretory activity. 相似文献
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8.
Z. D. Draganić S. I. Vujošević A. Negrón-Mendoza J. A. Azamar I. G. Draganić 《Journal of molecular evolution》1985,22(2):175-187
Summary We have examined a water-dominated multicomponent system after irradiation in the multimegarad dose range with gamma rays from a60Co source at both 77 and 310 K. The constituents were simple organic compounds in the proportions in which they appear in a dense interstellar cloud: HCN/CH3OH/CH3CN/C2H5CN/HCOOH=10.60.20.10.05. The total amounts were adjusted to correspond to a carbon to nitrogen ratio of 1.8 and a water content of about 50% in a cometary nucleus where the dust to volatiles ratio is 1; the total amount of CN-bearing compounds was taken to correspond to 0.4% of the cometary mass. In experiments at 310 K about 40 radiolytic products are identified, among them aldehydes and amino and carboxylic acids. Abundant polymeric material (Mw up to 80,000 daltons) is formed. The basic aspects of radiolysis of the liquid system are present also at 77 K, although at radiation-chemical yields that are lower by one to two orders of magnitude. We have considered the relevance of the present findings to the chemistry of a liquid-water core and the icy layers of a cometary nucleus. 相似文献
9.
Summary We have examined the radiolysis of an O2-free aqueous solution of glycine at absorbed doses of60Co gamma-radiation of up to 20 Mrad. At least 20 compounds are formed during radiolysis, among them several amino acids, an oligoamine, and the nitrogen-free polymers (Mw28,000 daltons). When dicyandiamide is present in the solution of glycine, various nitrogen-containing products, including some polymers (Mw12,000 daltons), are synthesized along with radiolytic products of glycine; polyglycines are not formed. We have determined the radiation-chemical yields of radiolytic-product formation and of decomposition of glycine, and have considered possible free-radical reactions leading to the radiation-induced changes observed. 相似文献
10.
The administration of diazepam 1.0 mg/kg decreased the level of plasma corticosterone in female but not in male Wistar rats. Picrotoxin, another drug affecting GABAergic transmission, also brought about an increase of plasma corticosterone in both sexes. However, in order to achieve a plasma corticosterone increase of similar magnitude (more than 500%) a threefold higher dose of picrotoxin had to be given to males. When the convulsive properties of picrotoxin were tested, it became evident that the dose of picrotoxin (2.5 mg/kg) which was subconvulsive in male was almost 100% convulsive in female rats. The existing sex differences in the response of rats to drugs affecting GABAergic transmission might have possible implications in the treatment of GABA system dysfunction. 相似文献