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Hannerz Harald; Albertsen Karen; Nielsen Martin Lindhardt; Tüchsen Finn; Burr Hermann 《Canadian Metallurgical Quarterly》2004,23(3):283
This study explored whether factors related to the work environment could predict changes in body mass index (BMI) and whether the effect of psychosocial factors was dependent on baseline BMI. The sample consisted of 1,980 male employees from the Danish National Work Environment Cohort Study. Changes in BMI between 1995 and 2000 were analyzed, by multiple regression, as a function of background variables and a series of occupational variables obtained in 1995. Age, baseline BMI, job insecurity, and psychological demands predicted changes in BMI. Job insecurity and high or low psychological demands increased the likelihood of weight gain among obese employees, whereas they increased the likelihood of weight loss among employees with a low BMI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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F Jónsson P Madsen LG J?rgensen M Lunding NH Secher 《Canadian Metallurgical Quarterly》1996,158(44):6256-6259
Indices of fluid balance were evaluated during and after aortic surgery in 16 consecutive patients. Thoracic electrical impedance (TI), heart rate (HR), central venous (CVP), pulmonary artery mean (PAMP), pulmonary wedge (PWP) and mean arterial (MAP) pressures as well as fourteen arterial and venous blood gas variables were followed. Consistent with a reduction of TI during the operation, fluid balance was in excess, and it remained elevated on the first postoperative morning. The HR, MAP and PWP remained stable, while CVP and PAMP decreased. Of the determined variables only TI revealed a meaningful correlation to fluid balance (rho = -0.41; p < 0.01). The results indicate that while central venous and pulmonary artery mean pressures gave the impression of a volume deficit, the positive fluid balance was mirrored by thoracic electrical impedance. 相似文献
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A new sub-class of binding protein-dependent transporter with specificity for a broad range of polar amino acids has been identified by sequence comparison, in Rhizobium leguminosarum, Rhodobacter capsulatus, Escherichia coli and Pseudomonas fluorescens. Southern blotting and PCR analysis has shown that transporters from this new sub-class are widely distributed in Gram-negative bacteria, including, in addition to the above, Citrobacter freundii, Erwinia carotovorum and Rhizobium meliloti. ABC transporters of polar amino acids can be divided into two groups: those with narrow solute specificity and the newly identified sub-class with broad solute specificity. The binding and inner membrane proteins from transporters with a broad solute specificity are larger by approximately 30% than those with a narrow solute specificity. Multiple alignment of the inner membrane proteins from all sequenced polar amino acid transporters indicates there is an N-terminal conserved region that may be involved in solute specificity. A conserved arginine or lysine at residue 30 of this region is changed to glutamate in arginine transporters. Residue 53 also has a strong correlation with the charge on the transported solute, with basic amino acid transporters replacing an aliphatic amino acid at this position with a negatively charged amino acid. The general amino acid permease from R. leguminosarum, which will transport aliphatic as well as basic and acidic amino acids, juxtaposes two prolines at residues 52 and 53 of the N-terminal conserved region. 相似文献
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Wayne Madsen 《Network Security》1998,1998(5):8-9
“We hear about mandatory access to encryption keys by law enforcement but nothing about privacy.” With that statement, Senator John Ashcroft of Missouri, an unannounced candidate for President in 2000, opened Senate Judiciary subcommittee hearings on the Clinton administration's doddering encryption policy. Ashcroft lambasted the administration for asking American citizens to turn over crypto keys to the government after it rifled through 1000 raw FBI files seeking political dirt on opponents. 相似文献
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A polarisation-independent four-port electro-optic tunable filter in the 1530 nm wavelength regime utilising non-polarising relaxed beam splitters and strain-induced polarisation converters on LiNbO3 with 16 nm tuning range and 46 ns tuning speed is reported. 相似文献
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Hallbjorner P. Carlberg U. Madsen K. Andersson J. 《Electromagnetic Compatibility, IEEE Transactions on》2005,47(2):291-303
Reverberation chambers can be used to measure the absorption cross section of a dielectric object. The absorption cross section of a dielectric object depends on its size, shape, and electrical material parameters. By comparing with a theoretical model of the absorption cross section, material parameters can be extracted from measurements. A model based on a plane wave approach of incident fields is used here, valid for electrically large material samples in an isotropic environment such as that in a reverberation chamber. Which material parameter can be extracted depends on the properties of the material sample. The presented method combines the accuracy of cavity methods with the flexibility of being able to measure samples of arbitrary size and shape. Because both the reverberation chamber and the material sample are electrically large, the method is particularly useful at millimeter-wave frequencies. 相似文献
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SJ Mihic Q Ye MJ Wick VV Koltchine MD Krasowski SE Finn MP Mascia CF Valenzuela KK Hanson EP Greenblatt RA Harris NL Harrison 《Canadian Metallurgical Quarterly》1997,389(6649):385-389
Volatile anaesthetics have historically been considered to act in a nonspecific manner on the central nervous system. More recent studies, however, have revealed that the receptors for inhibitory neurotransmitters such as gamma-aminobutyric acid (GABA) and glycine are sensitive to clinically relevant concentrations of inhaled anaesthetics. The function of GABA(A) and glycine receptors is enhanced by a number of anaesthetics and alcohols, whereas activity of the related GABA rho1 receptor is reduced. We have used this difference in pharmacology to investigate the molecular basis for modulation of these receptors by anaesthetics and alcohols. By using chimaeric receptor constructs, we have identified a region of 45 amino-acid residues that is both necessary and sufficient for the enhancement of receptor function. Within this region, two specific amino-acid residues in transmembrane domains 2 and 3 are critical for allosteric modulation of both GABA(A) and glycine receptors by alcohols and two volatile anaesthetics. These observations support the idea that anaesthetics exert a specific effect on these ion-channel proteins, and allow for the future testing of specific hypotheses of the action of anaesthetics. 相似文献