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61.
We have determined the free cortisol concentration in serum using either the Amicon MPS-1 ultrafiltration-centrifugation method (I) or equilibrium dialysis (II). If procedure I was used we found that [1,2,6,7-3H]-, and [4-14C]cortisol had a lower affinity than unlabelled cortisol for corticosteroid binding globulin (CBG). The binding affinity (Ka) to three separate CBG-containing samples was 8-18 times lower for [1,2,6,7-3H]cortisol and 30-90 times lower for [4-14C]cortisol, when compared with that of unlabelled cortisol. This difference in affinity to CBG was not observed if method II was used for the free cortisol determinations. The observed isotope effect in method I is not caused by unspecific binding to material such as the Amicon MPS-1 chamber or to impurities in the tracer. We suggest that the centrifugation step during ultrafiltration changed the conformation of CBG, thereby reducing its affinity for labelled cortisol. It is concluded that incorrect results will be obtained if radiolabelled is cortisol used for determining the free cortisol content of plasma with the Amicon MPS-1 device.  相似文献   
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63.
Addition of organic fillers to post‐consumer recycled plastics can give rise to several advantages. First of all, the cost of these fillers is usually very low, the organic fillers are biodegradable contributing to an improved environmental impact and, last but not least, some mechanical and thermomechanical properties can be enhanced. Organic fillers are not widely used in the plastic industry although their use is increasing. Bad dispersion into the polymer matrix at high‐level content and poor adhesion with the matrix are the more important obstacles to this approach. In this work various organic fillers have been used with a post‐consumer plastic material originating from films for greenhouses. The properties of these green composites have been compared with those of materials filled with a conventional inorganic filler. The organic fillers cause slightly worse processability, due to an increase of viscosity, an enhancement of the rigidity and of the thermomechanical resistance similar to that measured for the inorganic filler, while a reduction of the impact strength is observed. Copyright © 2004 Society of Chemical Industry  相似文献   
64.
Studied predictions of trends in psychotherapy over the next decade by 75 psychologists, using Delphi methodology. Directive, present-centered, problem-focused, and brief therapies were expected to increase, whereas historically oriented, comparatively passive, and long-term approaches were predicted to decrease. Self-help groups and social workers were expected to proliferate, while the proportion of psychotherapy provided by psychiatrists was expected to diminish. Integrative, systemic, and cognitive orientations will be in the ascendancy, as opposed to classical psychoanalysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
65.
In this study, we examined the mechanism by which bronchoalveolar lavage (BAL) cells induced hyperreactivity of the trachea in vitro. As both interleukin-5 (IL-5) and substance P (SP) appeared to be involved, the effect of these mediators was examined in vivo. Tracheae were incubated with BAL cells from ovalbumin or saline challenged animals, and from naive animals, in the absence or presence of either IL-5, SP, or both. In addition, the effect of intra-airway application of IL-5, SP, both, or vehicle on tracheal hyperreactivity was examined. Incubation of tracheae with BAL cells from ovalbumin challenged animals induced an increase (30 +/- 10%) in the maximal response to histamine. The hyperreactivity could be completely inhibited by co-incubation with 5-lipoxygenase inhibitor, AA861. The hyperreactivity could be mimicked by incubation of tracheae with BAL cells from naive animals in the presence of IL-5 and SP. After in vivo administration of either IL-5 or SP, maximal responses to histamine were increased and amounted to 105 +/- 35 and 101 +/- 37%, respectively. Administration of IL-5 but not SP induced a significant increase in the number of eosinophils (67 +/- 22%) and eosinophil peroxidase (EPO) activity (94 +/- 33%) in BAL cells. The simultaneous administration of IL-5 and SP did not potentiate the hyperreactivity and eosinophilia observed with IL-5 alone. These data suggest that IL-5 is important in the recruitment of eosinophils, whereas both IL-5 and substance P are involved in the induction of airway hyperreactivity.  相似文献   
66.
The URA3 gene of Candida utilis encoding orotidine-5'-phosphate decarboxylase enzyme was isolated by complementation in Escherichia coli pyrF mutation. The deduced amino-acid sequence is highly similar to that of the Ura3 proteins from other yeast and fungal species. An extensive analysis of the family of orotidine-5'-phosphate decarboxylase is shown. The URA3 gene of C. utilis was able to complement functionally the ura3 mutation of Saccharomyces cerevisiae.  相似文献   
67.
The adult gypsy moth, Lymantria dispar (Lymantriidae: Noctuoidea) has a pair of metathoracic tympanic ears that each contain a two-celled auditory chordotonal organ (CO). The earless forest tent caterpillar moth, Malacosoma disstria (Lasiocampidae: Bombycoidea), has a homologous pair of three-celled, nonauditory hindwing COs in their place. The purpose of our study was to determine whether the adult CO in both species arises from a preexisting larval organ or if it develops as a novel structure during metamorphosis. We describe the larval metathoracic nervous system of L. dispar and M. disstria, and identify a three-celled chordotonal organ in the anatomically homologous site as the adult CO. If the larval CO is severed from the homologue of the adult auditory nerve (IIIN1b1) in L. dispar prior to metamorphosis, the adult develops an ear lacking an auditory organ. Axonal backfills of the larval IIIN1b1 nerve in both species reveal three chordotonal sensory neurons and one nonchordotonal multipolar cell. The axons of these cells project into tracts of the central nervous system putatively homologous with those of the auditory pathway in adult L. dispar. Following metamorphosis, M. disstria moths retain all four cells (three CO and one multipolar) while L. dispar adults possess two cells that service the auditory CO and one nonauditory, multipolar cell. We conclude that the larval IIIN1b1 CO is the precursor of both the auditory organ in L. dispar and the putative proprioceptor CO in M. disstria and represents the premetamorphic condition of these insects. The implications of our results in understanding the evolution of the ear in the Lepidoptera and insects in general are discussed.  相似文献   
68.
About the 'Omnipotence' of the Chelation Therapy In the eighties the 'method of treatment proven in many thousands of cases over 20 years' was transferred from the USA to Germany (enjoys a priori considerable faith) using very dubious promises. It was Clarke et al. who introduced this 'therapy' in 1955. The dubious promise was to maintain that the chelation therapy eliminates or alleviates symptoms in the case of the following illnesses: Alzheimer's disease, senility, schizophrenia, rheumatoid arthritis, osteoarthritis, gout, renal calculus, apoplectic coma, gallstones, multiple sclerosis, osteoporosis, chronic fatigue syndrome, varicose veins, hypertension, failure of memory, scleroderma, Raynaud's disease, digitalis intoxication, intermittent claudication, diabetic ulcer, disturbance of the blood supply, ulcer on the legs, snake poison, impotence, emotional difficulties, defective hearing, vision disorder. There is not the slightest proof of effectiveness for any of the listed indications. The burden of proof lies with the supplier. Even in the case of the relatively often examined peripheral atherosclerotic changes (claudicatio intermittens) there is no proof that EDTA has a greater effect than placebo. For coronary heart disease too there is no evidence for any usefulness of the chelation therapy beyond that of a placebo effect. Only controlled studies can help to improve the therapy in the sense of 'Evidence-based medicine'. Retrospective investigations on thousands of patients cannot 'prove' anything, although this is maintained again andagain.  相似文献   
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70.
High-permittivity and low-loss ceramics with composition BaTi0.92Ga0.08O2.96 have been prepared in the BaO–Ga2O3–TiO2 system using the mixed-oxide route. This compound forms as the hexagonal polymorph (6 H ) of BaTiO3 with the space group P 63/ mmc . The dielectric properties of dense ceramics have been studied, at microwave frequencies, with the ceramics fired at 1450°C under flowing oxygen gas; the results are a relative permittivity, ɛr, of ∼74 and a quality factor, Q · f r, of ∼7815 at 5.5 GHz. The quality factor is strongly influenced by the sintering conditions (temperature and atmosphere), whereas the relative permittivity is not influenced significantly by ceramic processing for pellets ≥93% of the theoretical X-ray density. To our knowledge, this is the first report of microwave dielectric resonance in a perovskite-type BaTiO3-based ceramic.  相似文献   
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