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21.
Muhvić-Dimanovski V 《Collegium antropologicum》2004,28(Z1):139-146
It is a well-known fact that languages react differently when foreign words denoting new concepts have to be integrated into the native system. The procedure mostly depends on the degree of purism present in a linguistic community: some languages are rather open to foreign influences and do not demonstrate any special hostility towards new words which are easily accepted and adapted to the phonological and morphological systems of the receiving language. Languages, which have a strong puristic tradition, usually channel their borrowings into the loan translation field using internal word formation resources as a means of creating neologisms. Regardless of whether they are built of native elements or appear as loans, neologisms are necessarily the result of linguistic changes. 相似文献
22.
Djinović V Momcilović M Grgurić-Sipka S Trajković V Mostarica Stojković M Miljković D Sabo T 《Journal of inorganic biochemistry》2004,98(12):2168-2173
A novel class of ruthenium (III) complexes of formulas K[Ru(sar)2Cl2].12H2O and K2[Ru(dmgly)Cl4].2H2O, containing bidentate chelates N-methylglycine (sarcosine, sar) or N,N-dimethylglycine (dmgly) and additional chloro ligands were synthesized. The complexes have been obtained by direct reaction of ruthenium(III) chloride with corresponding bidentate ligand followed by addition of base (KOH). These new complexes were characterized by elemental analysis, IR and electronic absorption spectroscopy. As astrocytomas, the most common of all brain tumors, are still very difficult to treat, we examined the influence of newly synthesized ruthenium-based complexes, as well as the earlier synthesized analogue platinum(IV) complexes [Pt(dmgly)2Cl2], [Pt(sar)2Br2] and [Pt(dmgly)2Br2], on rat astrocytoma C6 cells in vitro. Among these complexes only K2[Ru(dmgly)Cl4].2H2O and [Pt(dmgly)2Br2] markedly inhibited the viability of non-confluent C6 cells. Furthermore, only complex K2[Ru(dmgly)Cl4].2H2O was able to reduce viability in confluent C6 cultures. Importantly, this complex was not toxic to primary rat astrocytes or macrophages. Having in mind that appropriate chemotherapy should be effective against tumor cells without harming normal tissues, complex K2[Ru(dmgly)Cl4].2H2O could be a promising agent for developing therapeutics against astrocytomas. 相似文献
23.
Brkljacić JM Samardzić JT Timotijević GS Maksimović VR 《Journal of plant physiology》2004,161(6):741-746
The buckwheat metallothionein-like (MT3) gene expression was studied throughout seed and leaf development, as well as under the influence of different external stimuli. MT3 mRNAs were detected from the early stage of seed development to the end of maturation, reaching the highest level during the mid-maturation stage. High MT3 mRNA level was noticed for both green and senescent leaves. The influence of raising Cu ion concentrations on MT3 gene expression was studied only in leaves, while the effect of Zn ions was analyzed through seed development as well. It was found that Cu and Zn ions had stimulatory effects on expression in leaves. MT3 expression was significantly enhanced in the early stage of seed development in response to Zn ions, while after this stage, influence of Zn ions was not detected. After H2O2/NaCl treatment, MT3 mRNA level was decreased in green leaves, contrary to senescent leaves where expression levels remained unchanged. H2O2 treatment caused the increase of MT3 mRNA levels in the mid-maturation stage of seed development. NaCl had no effect on expression levels in seeds. According to obtained results, proposed functions in different plant organs regarding oxidative stress and metal homeostasis are discussed. 相似文献
24.
Zivicnjak M Narancić NS Szirovicza L Franke D Hrenović J Bisof V 《Collegium antropologicum》2003,27(1):321-334
In a cross-sectional study of growth, 5,155 children (2,591 females, 2,564 males) from the town of Zagreb (Croatia) were measured. Four traits of linear dimensionality (stature, sitting height, arm and leg lengths) were studied in the age span of 3 to 18 years. A significant average annual increase of all four anthropometric parameters were observed up to 14 and 15 years of age in girls and 16 years of age in boys, showing that girls had a shorter growing period. In the prepubertal period until 9 years of age, gender differences were negligible. At the age of 10, boys were overgrown by girls in all parameters due to the earlier onset of puberty in girls. The growth gains for girls, when compared with those for boys, show a different pattern across variables. The female growth advantage remained in a two years period for the limbs length, but in a three year period for stature and the longest, for 4 years, for sitting height. The male predominance in size had an onset at the age of 13 for the limbs and in the age of 14 for stature and sitting height. The patterns of sexual dimorphism in stature and sitting height during growing years are similar to those observed in other populations of Europe. Growth of Croatian children and youth is very similar to that of the tallest European populations. 相似文献
25.
Ilijin L Janković-Tomanić M Mitić M Vlahović M Lazarević J Perić-Maratuga V Prolić Z Nenadović V 《Folia biologica》2003,51(3-4):207-211
The response of Morimus funereus larvae to total starvation and refeeding with qualitatively different nutritive substrates (artificial diets supplemented with yeast as a source of B complex vitamins or with a digestibility reducer-tannic acid) was examined in this paper. Refeeding resulted in a compensatory increase of larval growth. Feeding and refeeding with qualitatively different nutritive substrates affected both quality and quantity of midgut and brain proteins. The observed differences suggest the possible switching of enzyme isoforms in M. funereus midgut and changes in synthesis/secretion of neurohormones, depending on food presence and its nutritional value. 相似文献
26.
Sexual differences in reaction norms of life history traits (larval development time--LDT, pupal weight--PW and adult longevity--L) were investigated in the gypsy moth reared on young or old oak leaves during the first larval instar. Sexual dimorphism was revealed for genetic variation in reaction norms that was expressed only for LDT in males, and PW and L in females. Higher mean plasticity of longevity was found in males compared to females indicating that the sexes are exposed to divergent selective pressures. Greater dependence of males on energy resources (carbohydrates and lipids) may account for the observed differences. 相似文献
27.
Membrane localization of motility,signaling, and polyketide synthetase proteins in Myxococcus xanthus
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Myxococcus xanthus cells coordinate cellular motility, biofilm formation, and development through the use of cell signaling pathways. In an effort to understand the mechanisms underlying these processes, the inner membrane (IM) and outer membrane (OM) of strain DK1622 were fractionated to examine protein localization. Membranes were enriched from spheroplasts of vegetative cells and then separated into three peaks on a three-step sucrose gradient. The high-density fraction corresponded to the putative IM, the medium-density fraction corresponded to a putative hybrid membrane (HM), and the low-density fraction corresponded to the putative OM. Each fraction was subjected to further separation on discontinuous sucrose gradients, which resulted in discrete protein peaks for each major fraction. The purity and origin of each peak were assessed by using succinate dehydrogenase (SDH) activity as the IM marker and reactivities to lipopolysaccharide core and O-antigen monoclonal antibodies as the OM markers. As previously reported, the OM markers localized to the low-density membrane fractions, while SDH localized to high-density fractions. Immunoblotting was used to localize important motility and signaling proteins within the protein peaks. CsgA, the C-signal-producing protein, and FibA, a fibril-associated protease, were localized in the IM (density, 1.17 to 1.24 g cm(-3)). Tgl and Cgl lipoproteins were localized in the OM, which contained areas of high buoyant density (1.21 to 1.24 g cm(-3)) and low buoyant density (1.169 to 1.171 g cm(-3)). FrzCD, a methyl-accepting chemotaxis protein, was predominantly located in the IM, although smaller amounts were found in the OM. The HM peaks showed twofold enrichment for the type IV pilin protein PilA, suggesting that this fraction contained cell poles. Two-dimensional polyacrylamide gel electrophoresis revealed the presence of proteins that were unique to the IM and OM. Characterization of proteins in an unusually low-density membrane peak (1.072 to 1.094 g cm(-3)) showed the presence of Ta-1 polyketide synthetase, which synthesizes the antibiotic myxovirescin A. 相似文献
28.
Synthesis and intramolecular transesterifications of pivaloylated methyl alpha-D-galactopyranosides 总被引:1,自引:0,他引:1
Selective pivaloylations of methyl alpha-D-galactopyranoside have been studied under various reaction conditions. Partially pivaloylated products were submitted to additional acetylations. The structures were established by 1H and 13C NMR spectroscopies. Both, 2,6- and 3,6-dipivalates underwent intramolecular cyclization in neutral conditions (phosphate buffered saline, pH 7.2) to give a stable 2,3-orthoacid with a parallel 6-->4 migration of the pivaloyl group. 相似文献
29.
Simulations were done of the electron paramagnetic resonance (EPR) spectra for bis(N,N-dimethyl-L-alpha-isoleucinato)copper(II) dissolved in deuterated methanol as a function of temperature. They indicated different behaviour of the complex below and above 300 degrees K. The effect was examined by the conformational analysis of the copper(II) complex with a new molecular mechanics force field. 相似文献
30.
The US Food and Drug Administration (FDA) has regulatory authority over foods, human drugs, cosmetics, medical devices, radiological products, biologics, and veterinary products. Among these products, FDA believes that the use of medical devices, including medical gloves, condoms, catheters, and breathing bags, represents the greatest source of natural latex proteins to exposed individuals. A medical device is defined in the Federal Food Drug and Cosmetic Act (FFDCA) as an instrument, apparatus, implement, machine, etc., that is intended for use in the diagnosis or treatment of disease or is intended to affect the structure or any function of the body of a human or other animal, and that does not achieve any of its principal intended purposes through chemical action in the body. This article provides some brief, general background about FDA's medical device regulatory process and then addresses the issue of natural latex allergy. Finally we discuss the steps the Agency has taken to evaluate the magnitude and nature of the problem, and FDA's efforts to assist manufacturers, health professionals, and others in minimizing exposure and sensitization to natural latex proteins in medical devices. 相似文献