共查询到20条相似文献,搜索用时 0 毫秒
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Ramon Buxó 《Vegetation History and Archaeobotany》2008,17(1):145-154
The Iron Age archaeobotanical record on the Iberian Peninsula shows how the Phoenician and Greek colonisers caused the indigenous
Iberians to change the management of the agricultural resources and the crops which they grew. These colonisers also brought
about the development of viticulture and olive cultivation. The importance of agricultural products in the trade network which
was stimulated by the colonisers may have encouraged new farming systems, as well as surplus capacity in the native agriculture
in the region. 相似文献
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Peng Wang Juan Li Li Wang Ming-li Tang Zeng-liang Yu Zhi-ming Zheng 《Journal of industrial microbiology & biotechnology》2009,36(11):1363-1368
Low-energy ion beam irradiation (10–200 keV) has been proved to have a wide range of biological effects in recent years. When
Rhizopus oryzae PW352 was irradiated with a 15-keV low-energy ion beam an l(+)-lactic acid high-yield mutant, RQ4015, was obtained. When 150 g/l glucose was used as the sole carbon source, l(+)-lactic acid of RQ4015 reached 121 g/l after 36 h shake-flask cultivation. However, the highest lactic acid concentration
74 g/l was obtained when 100 g/l xylose was present in the medium as the sole carbon source. When mixed xylose (25 g/l) and
glucose (75 g/l) were present in a bubble column, l(+)-lactic acid production of RQ4015 reached 83 g. A high mutation rate and a wide mutation spectrum of low-energy ion implantation
were observed in the experiment, suggesting that ion implantation can be a highly efficient mutagenic means for microorganism
breeding in many commercial applications. 相似文献
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Eun-Seon Seo Yu-Ri Lim Yeong-Su Kim Chang-Su Park Deok-Kun Oh 《Biotechnology and Bioprocess Engineering》2010,15(4):590-594
The bacterium Bacillus licheniformis, which exhibits high hydrolytic activity toward arabinan, was isolated from soil, and its gene encoding endo-1,5-α-l-arabinanase was cloned and sequenced. The gene has an open reading frame that encodes 328 amino acids, including a signal
peptide of 37 amino acids. Endo-1,5-α-l-arabinanase, a member of glycosyl hydrolase family 43, was expressed in Escherichia coli and purified as a 34-kD monomer with a specific activity of 27 U/mg. Optimal activity toward debranched arabinan (linear
1,5-α-l-arabinan) occurred at pH 6.0 and 35°C, with a k
cat of 160/sec and a K
m of 19 mg/mL. 相似文献
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Complex (S,S)-[Pd{C6H4(CH2CHNH2CO2CH2CH3)}(μ-Br)]2 (3) was prepared following the method by Vicente and Saura-Llamas (Organometallics 26:2768–2776, 2007), by the reaction of l-ethylphenylalanate and Pd(OAc)2 in 1:1 molar ratio under acetonitrile heating conditions and subsequently treating with NaBr. In addition, the cleavage of
halogeno-bridge of the complex 3 via nucleophilic attack of some neutral ligands such as triphenylphosphine, pyridine, 2,4,6-trimethylpyridine and piperidine
were investigated and the corresponding complexes (S)-[Pd{C6H4(CH2CHNH2CO2CH2CH3)(Y)(Br)}] (4a–f) were obtained in moderate yields. The six-member orthopalladated complexes were characterized by 1H-NMR, 31P-NMR, FT-IR and elemental analysis techniques. 相似文献
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O. V. Golovanova V. I. Konenkov A. V. Shevchenko M. V. Smolnikova 《Russian Journal of Genetics》2009,45(8):981-986
Based on population analysis of the DRB1, DQA1, DQB1 and TNFA allele frequency distribution patterns, regional features of immunogenetic structure of the population of West Siberia were
investigated. Statistically significant linkage disequilibrium within the HLA class II region, as well as between the TNFA and DRB1, DQA1, and DQB1 was demonstrated. Population frequency distribution patterns of two- and multilocus haplotypes were examined. 相似文献
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Joanna Saluk-Juszczak Beata Olas Barbara Wachowicz Rafal Glowacki Edward Bald 《Cell biology and toxicology》2010,26(4):355-365
The oxidative stress induced by acute exertion may interfere with blood platelet activation. The beneficial effect of l-carnitine (γ-trimethylamino-β-hydroxybutyric acid) on oxidative stress in blood platelets has not been fully investigated;
however, different studies indicate that this compound modulates platelet functions. The aim of our study was to assess the
effects of l-carnitine on platelet activation and oxidative/nitrative protein damage (determined by the levels of protein carbonyl groups,
thiol groups, and 3-nitrotyrosine residues) in resting blood platelets or platelets treated with peroxynitrite (ONOO−, a strong physiological oxidant) in vitro. We also investigated the effects of l-carnitine on the level of platelet glutathione and on the formation of superoxide anion radicals ( O2 - · ) \left( {{\hbox{O}}_2^{ - \bullet }} \right) , lipid peroxidation measured by thiobarbituric acid reactive substances (TBARS) in blood platelets stimulated by thrombin
(a strong physiological agonist), and platelet aggregation induced by adenosine diphosphate (a strong physiological stimulator).
We have observed that carnitine decreases platelet activation (measured by platelet aggregation, the generation of O2 - · {\hbox{O}}_2^{ - \bullet } , and TBARS production). Moreover, our results in vitro demonstrate that carnitine may protect against oxidation of thiol
groups induced by ONOO−. Thus, carnitine may have some protectory effects against oxidative changes induced in blood platelets. 相似文献
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Eiichi Sakurai Eiko Sakurai Yukari Ueda Yasuyuki Yagi 《Biological trace element research》2011,142(3):713-722
The aim of this study was to examine enhancing effect of l-histidine into cultured rat lung microvascular endothelial cells (LMECs), which constitute the gas–blood barrier. Uptake
of l-histidine into LMECs markedly increased with the addition of ZnSO4 (0.1 mmol/L), and this enhanced uptake of l-histidine was drastically reduced in the presence of the Na+-independent system L substrate, 2-amino-2-norbornanecarboxylic acid (BCH). However, the uptake of l-histidine together with ZnSO4 was not reduced by the addition of metabolic inhibitor, 2,4-dinitrophenol, or sodium ion replacement. Moreover, the addition
of the system N-substrate, l-glutamic acid γ-monohydroxamate did not significantly decrease the uptake of l-histidine with 143 mmol/L Na + + 1 mmol/L BCH. These results indicated that system-N transporter does not play a role in the uptake of l-histidine in the presence of ZnSO4, suggesting that only system-L transporter is involved in the uptake of l-histidine, although l-histidine in the absence of ZnSO4 was taken up by at least two pathways of Na+-dependent system-N and Na+-independent system-L processes into rat LMECs. The uptake of l-histidine into rat LMECs in the presence of ZnSO4 was also found to be unaffected by pH (5.0–7.4), indicating that uptake of l-histidine into LMECs by the addition of zinc may not be involved in the H+-coupled transporters. 相似文献
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There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes:
Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial
agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed. 相似文献
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D. V. Fedorov S. V. Kovaltzova V. T. Peshekhonov V. G. Korolev 《Russian Journal of Genetics》2010,46(6):659-665
The yeast genes IXR1 and HMO1 encode proteins belonging to the family of chromatin nonhistone proteins, which are able to recognize and bind to irregular
DNA structures. The full deletion of gene IXR1 leads to an increase in cell resistance to the lethal action of UV light, γ-rays, and MMS, increases spontaneous mutagenesis and significantlly decreases the level of UV-induced mutations. It was earlier
demonstrated in our works that the hmo1 mutation renders cells sensitive to the lethal action of cisplatin and virtually does not affect the sensitivity to UV light.
Characteristically, the rates of spontaneous and UV-induced mutagenesis in the mutant are increased. Epistatic analysis of
the double mutation hmo1 ixr1 demonstrated that the interaction of these genes in relation to the lethal effect of cisplatin and UV light, as well as UV-induced
mutagenesis, is additive. This suggests that the products of genes HMO1 and IXR1 participate in different repair pathways. The ixr1 mutation significantly increases the rate of spontaneous mutagenesis mediated by replication errors, whereas mutation hmo1 increases the rate of repair mutagenesis. In wild-type cells, the level of spontaneous mutagenesis was nearly one order of
magnitude lower than that obtained in cells of the double mutant. Consequently, the combined activity of the Hmo1 and the
Ixr1 proteins provides efficient correction of both repair and replication errors. 相似文献
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