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171.
W Sch?nzer 《Canadian Metallurgical Quarterly》1996,42(7):1001-1020
Anabolic androgenic steroids (AAS) are misused to a high extent in sports by athletes to improve their physical performance. Sports federations consider the use of these drugs in sports as doping. The misuse of AAS is controlled by detection of the parent AAS (when excreted into urine) and (or) their metabolites in urine of athletes. I present a review of the metabolism of AAS. Testosterone is the principal androgenic steroid and its metabolism is compared with that of AAS. The review is divided into two parts: the general metabolism of AAS, which is separated into phase I and phase II metabolism and includes a systematic discussion of metabolic changes in the steroid molecule according to the regions (A-D rings), and the specific metabolism of AAS, which presents the metabolism of 26 AAS in humans. 相似文献
172.
173.
Weijing He Haiyan Li Siu-Lun Fok J. Derek Jackson Jan R. Wright 《Nuclear Engineering and Design》2007,237(12-13):1437-1444
A series of quench tests on hollow cylindrical specimens made of the machinable ceramic, Pyrophyllite, has been performed. The specimens consistently fractured with two diametrically opposite longitudinal cracks. Finite element analysis indicates that the primary crack occurred at the stage when the strain energy of the cylinder reached its maximum during the thermal transient process, while the secondary crack was caused by stress waves generated following the primary crack. This is supported by experimental observation of the time of fracture and the crack morphology. The work reported here helps to shed light on the fracture criterion for brittle cylindrical components under transient thermal and dynamic loadings. 相似文献
174.
175.
176.
T Forst A Pfützner P Kann B Schehler R Lobmann H Sch?fer J Andreas A Bockisch J Beyer 《Canadian Metallurgical Quarterly》1995,12(10):874-879
Alterations in bone metabolism in diabetes mellitus is a topic of special interest. Bone blood flow is increased in the distal limb of diabetic patients, which is believed to increase osteoclastic activity. We measure bone mineral density using dual-photon absorptiometry in the distal lower limb, the femoral neck, and the lumbar spine in 41 IDDM patients and in 30 control persons. In the diabetic group there was a 10% reduction of bone mineral density in the femoral neck (p < 0.01) and a 12% reduction in the distal limb (p < 0.001) compared with the control group. No significant difference was found in the lumbar spine (p = 0.22). Our data yield incidence for peripheral osteopenia in IDDM-patients, independent of any systemic bone disease such as osteoporosis. A link between decreased bone mineral density and diabetic neuropathy has been observed for the femoral neck (p < 0.001), but not for the distal limb or axial skeleton. Whether there is a common aetiological link or a casual connection between diabetic neuropathy and bone mineral density has still to be determined. 相似文献
177.
Maciej Winiewski Artur Jakubiak Jan Szymanowski 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,63(3):209-214
Decyl isonicotiniate and decyl nicotiniate permit a rapid extraction of palladium(II) from its hydrochloride solutions. Decyl picoliniate is not a suitable extractant. 4-Octylphenylamine can act as a phase transfer catalyst when its concentration in the organic phase is at least 2·5 × 10?4 M . It seems that the interfacial adsorption of pyridine carboxylates and of 4-octylphenylamine is not the decisive phenomenon in palladium(II) extraction. The negligible protonation of the pyridine-type extractants and the phase transfer catalysis explains well the quick extraction of palladium(II) with the commercial and highly hydrophobic extractant ACORGA CLX-50. 相似文献
178.
Jerzy Stangierski Jan Zabielski Jacek Kijowski 《European Food Research and Technology》2007,226(1-2):233-237
The effect of addition of 3 g/L of commercially available transglutaminase preparation to protein extracts obtained from mechanically
recovered poultry meat was studied. The content of free thiol groups (–SH), thermal drip and gel texture were determined.
After pre-incubation at 7–8 °C for 1, 3, 5 and 24 h, the samples were subjected to one-step heating at 50, 60, 70 and 80 °C
and two-step heating at 50/80, 55/80 and 60/80 °C. The addition of preparation and the extension of pre-incubation time led
to decrease of free -SH groups content. After heating, the number of thiol groups decreased, the texture was improved, but
thermal drip from gels increased. The amount of –SH groups in gel extracts subjected to one-step heating decreased with simultaneous
increase of mechanical strength of gels. Protein gels subjected to two-step heating exhibited higher firmness than gels subjected
to one-step heating. Thus, the 3 g/L addition of transglutaminase preparation in combination with one-step thermal processing
at 70 °C and pre-incubation for 3 h contributed to improvement of texture properties of model gels and low thermal drip. 相似文献
179.
Discusses the Dutch health system, focusing on the increasing number of clinical psychologists who are offering their services to the public as private practitioners. This move toward primary health care given by the "first-line psychologist" results from a generalistic frame of reference in which a wide range of psychic, psychosocial, and psychosomatic difficulties are treated with a time-limited framework. In this way, the clinical psychologist contributes to changing the habits and lifestyles of a broad population. Responses to the system are encouraging, and the government has begun to respond positively to the system. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
180.
Gerhard Jäger 《Journal of Logic, Language and Information》2002,11(4):427-451
In this paper, we discuss some formal properties of the model ofbidirectional Optimality Theory that was developed inBlutner (2000). We investigate the conditions under whichbidirectional optimization is a well-defined notion, and we give aconceptually simpler reformulation of Blutner's definition. In thesecond part of the paper, we show that bidirectional optimization can bemodeled by means of finite state techniques. There we rely heavily onthe related work of Frank and Satta (1998) about unidirectionaloptimization. 相似文献