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31.
许松华 《建筑创作》2011,(4):124-133
自1997年至2009年,仅短短12年的时间,哈萨克斯坦的首都阿斯塔纳以令人难以置信的速度变成了一个新兴的城市,在这个位于北京和莫斯科之间的哈萨克大草原上,通过国际招标和竞赛、由黑川纪章等一批当今国际知名的建筑师科学设计的总体规划,创造了一个连接亚洲和欧洲的新桥梁。由意大利建筑师Manfredi Nicoletti设计的阿斯塔纳中央音乐厅于2009年12月正式开放,该项目的设计理念就是使建成后的音乐厅成为宽阔空旷大地的一朵"草原之花",正是基于这一理念,使其在2003年的国际竞赛中脱颖而出、拔得头筹。音乐厅占地54 000m~2,位于总统府和参议院大厦之间,其花瓣形的建筑构造交织错落,这些用蓝色玻璃板组成的"花瓣"内,包括了3500席的大型音乐厅和一个面积近3000m~2、30m  相似文献   
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In order to assess the current level of resistance to widely used antipseudomonal antibiotics in clinical isolates of Pseudomonas aeruginosa, a national survey was undertaken. Fifteen hospitals throughout Italy participated in the study. The University of Catania tested the antibiotic susceptibility of 1005 consecutive clinically significant P. aeruginosa collected from March to June 1995. Lack of susceptibility, according to NCCLS breakpoints, was at the following rates: meropenem, 9.1%; imipenem, 19.3%; ceftazidime, 13.4%; carbenicillin, 27.3%; piperacillin, 12%; ticarcillin/clavulanic acid, 22.8%; amikacin, 10.6%; and ciprofloxacin, 31.9%. About half of the isolates (44.4%) were not susceptible to at least one of the antibiotics tested.  相似文献   
34.
OBJECTIVES: This study compared the long-term effects of complete atrioventricular junction (AVJ) ablation with those of AVJ modification in patients with medically refractory atrial fibrillation (AF). BACKGROUND: Comparisons between the long-term effects of AVJ ablation with those of AVJ modification in patients with medically refractory AF have not been systematically studied. METHODS: Sixty patients with medically refractory AF were randomly assigned to receive complete AVJ ablation with permanent pacing or AVJ modification. Subjective perception of quality of life (QOL) was assessed by a semiquantitative questionnaire before and 1 and 6 months after ablation. Cardiac performance was evaluated by echocardiography and radionuclide angiography within 24 h (baseline) and at 1 and 6 months after ablation. RESULTS: Both methods were associated with significant improvement in general QOL and a significant reduction in the frequency of major symptoms and symptoms during attacks. The frequency of hospital admission and emergency room visits and antiarrhythmic drug trials significantly decreased after ablation in both groups. However, patients after complete AVJ ablation had a significantly greater improvement in general QOL and a significantly reduced frequency of major symptoms and symptoms during attacks (including palpitation, dizziness, chest oppression, blurred vision and syncope). Left ventricular (LV) systolic function and the ability to perform activities of daily life significantly improved after ablation in patients with depressed LV function in both groups. All improvements after ablation or modification were maintained over the 6-month follow-up period. CONCLUSIONS: AVJ ablation with permanent pacing, as compared with AVJ modification, had a significantly greater ability to decrease the frequency of attacks and the extent of symptoms of AF, and the patients who received this procedure were more satisfied with their general well-being.  相似文献   
35.
The inhibitory activity of a truncated derivative of the natural amphibian skin peptide dermaseptin s3-(1-16)-NH2 [DS s3 (1-16)] against Saccharomyces cerevisiae was studied. Significant growth inhibition was observed after exposure to 3.45 microgram of the peptide per ml at pH 6.0 and 7.0, with complete growth inhibition occurring at 8.63 microgram of peptide per ml for all pH values tested. Using confocal scanning laser microscopy, we have shown that DS s3 (1-16) disrupted the yeast cell membrane resulting in the gross permeabilization of the cell to the nuclear stain ethidium bromide. However, the principal inhibitory action of the peptide was not due to disruption of intracellular pH homeostasis. Instead, growth inhibition by the peptide correlated with the efflux of important cellular constituents such as ADP, ATP, RNA, and DNA into the surrounding medium. The combination of DS s3 (1-16) with mild heating temperatures as low as 35 degreesC significantly enhanced the inhibitory effect of the peptide (8.63 microgram/ml), and at 45 degreesC greater than 99% of the population was killed in 10 min. In summary, a derivative of a natural antimicrobial peptide has potential, either alone or in combination with mild heating, to prevent the growth of or kill spoilage yeast.  相似文献   
36.
Adenylate kinase (AK), which catalyzes the equilibrium reaction among AMP, ADP, and ATP, is considered to participate in the homeostasis of energy metabolism in cells. Among three vertebrate isozymes, AK isozyme 1 (AK1) is present prominently in the cytosol of skeletal muscle and brain. When mouse embryonal carcinoma P19 cells were differentiated by retinoic acid into neural cells, the amount of AK1 protein and enzyme activity increased about fivefold concomitantly with neurofilament (NF). Double-immunofluorescence staining showed that both AK1 and NF were located in neuronal processes as well as the perinuclear regions in neuron-like cells, but not in glia-like cells. The amount of brain-type creatine kinase increased only twofold during P19 differentiation. The AK isozyme 2, which was not detected in adult mouse brain, was found in P19 cells and did not increase during the differentiation. Mitochondrial AK isozyme 3, which uses GTP instead of ATP as a phosphate donor, was increased significantly. Immunohistochemical analysis with the primary cultured cells from rat cerebral cortex showed similar cellular localization of AK1 to those observed with differentiated P19 cells. These results suggest an important role of this enzyme in neuronal functions and in neuronal differentiation.  相似文献   
37.
The computer has strongly influenced the way firms are managed. In the airline industry, however, computers have always been closely associated with the communication networks. Such a symbiosis has influenced, and will influence more and more the very nature of the airline industry. This concept is explored by describing the state of the art and by outlining some future developments.  相似文献   
38.
The study presented in this paper aims at improving the current understanding of human-robot interaction by adopting a psychological approach. The acceptability of robotic devices in home settings, especially by elderly people, does not depend only on the practical benefits they can provide, but on complex relationships between the cognitive, affective and emotional components of peoples images of robots. This study has investigated the main dimensions of these representations, by comparing the attitudes towards technology in general, and domestic robots in particular, held by people at different stages of the lifespan. The results confirm that age is a critical variable.  相似文献   
39.
A new pillared cerium(IV) sulfate–diphosphonate with formula Ce2(2H2O)[(O3PCH2)–NC10H18N–(CH2PO3)(SO4)2] · 6H2O has been hydrothermally synthesized and its structure has been solved ab initio from laboratory X-ray powder diffraction data.The luminescent and thermal properties of this compound have been preliminarily studied and the encouraging results place it in the field of functional hybrid materials.  相似文献   
40.
The profiles of volatile chemicals emitted by Vicia faba plants damaged by Lygus rugulipennis feeding, and by feeding plus oviposition, were shown to be quantitatively different from those released by undamaged plants. Samples of volatile chemicals collected from healthy plants, plants damaged by males as a consequence of feeding, plants damaged by females as a consequence of feeding and oviposition, plants damaged by feeding with mated males still present, and plants damaged by feeding and oviposition with gravid females still present, showed significant differences in the emission of hexyl acetate, (Z)-β-ocimene, (E)-β-ocimene, (E)-β-caryophyllene, and methyl salicylate. In particular, treatments with mated females present on plants had a significant increase in emission levels of the above compounds, possibly due to eggs laid within plant tissues or active feeding, compared with undamaged plants and plants damaged by males feeding, with or without insects still present. Furthermore, the pheromonal blend released by mated L. rugulipennis females, mainly comprising hexyl butyrate, (E)-2-hexenyl butyrate, and (E)-4-oxo-2-hexenal, was enhanced when females were active on broad bean plants, whereas such an increase was not observed in males. Both sexes gave electroantennogram responses to green leaf volatiles from undamaged plants and to methyl salicylate and (E)-β-caryophyllene emitted by Lygus-damaged plants, suggesting that these compounds may be involved in colonization of host plants by L. rugulipennis. In addition, mated males and females were responsive to hexyl butyrate, (E)-2-hexenyl butyrate, and (E)-4-oxo-2-hexenal released by mated females on V. faba, indicating that these substances could have a dual function as a possible aggregation pheromone in female–female communication, and as a sex pheromone in female–male communication. An erratum to this article can be found at  相似文献   
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