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91.
DM Tomkins SV Otton N Joharchi T Berns D Wu WA Corrigall EM Sellers 《Canadian Metallurgical Quarterly》1997,8(2-3):223-235
In rats, amphetamine (AMP) conversion to 4-OH-AMP is metabolized by CYP2D1, the rat equivalent of the human enzyme CYP2D6. To determine the impact of impaired AMP metabolism on its behavioural effects, AMP-induced hyperactivity, AMP discrimination and AMP self-administration were examined in male Wistar rats with or without pretreatment with the CYP2D1 inhibitors quinine and budipine. In vivo, quinine (20 mg/kg) and budipine (10 mg/kg) increased the plasma area under the curve of AMP 4-fold and 3.6-fold respectively, and decreased the plasma levels of 4-OH-AMP, 3-fold and 8.6-fold, confirming that the doses used suppressed CYP2D1 activity. Both inhibitors prolonged AMP-induced hyperactivity (0.3 mg/kg) and prolonged the duration of AMP-appropriate responding for periods of up to 90 min post-AMP administration in a drug discrimination procedure. In rats given a preload dose of AMP (0.8 mg/kg) 3 h prior to the self-administration test session, CYP2D1 inhibition resulted in fewer AMP infusions being taken compared with rats receiving the AMP preload dose alone. These studies indicate that AMP is responsible for the behavioural effects seen in rats and that a rat phenocopy model of the human CYP2D6 deficiency state can be produced by CYP2D1 inhibitors. 相似文献
92.
93.
EP Kudriavtsev SI Miroshin SV Semenov AS Snigorenko IA Sidorovich 《Canadian Metallurgical Quarterly》1997,(3):36-41
The functional status of the oxidative-antioxidative system was studied in 72 patients after vast cancer operations. Traditional surgical treatment and its combination with intraoperative irradiation were shown to lead to tense antioxidative defense and to suppressed T-cell immunity and to call for antioxidative and immunomodulating therapy. High intraoperative blood loss complicated by hemorrhagic shock injured the oxidative-antioxidative system greatly. The magnitude of this damage correlated with the rate of prehypoxia. Addition of the potent antioxidant Ceruloplasmin to the drug regimen normalized a recovery period, helped to correct posthypoxic multiorgan insufficiency, to recover oxidative-antioxidative balance, and to decrease the incidence of pyoinflammatory complications. Patients with endogenous intoxication showed activated lipid peroxidation, decreased functional activity of antioxidative defense components and of T-cell immunity in homeostasis. The use of Ceruloplasmin and Laprot had pronounced antiinflammatory and detoxifying effects on the patient's body and activated its antioxidative defense. 相似文献
94.
IV Ga?voronski? LP Tikhonova SV Chepur GI Nichiporuk 《Canadian Metallurgical Quarterly》1997,112(6):33-37
An original quantitative examination of oxidation-reduction enzymes activity in endotheliocytes of hemomicroclrculatory vessels of jejunum and rectum submucosal base in normal state and in portal hypertension was performed by the authors. Comparative analysis of the activity of the enzymes studied revealed different metabolic processes intensity in these organs, dependent on current hemodynamic conditions. Cytochemical changes in hemomicrocirculatory bed are consistent with structural reorganizations that arise in the wall of vessels studied, consist of several phases and may be used as an assessment criterion for defining the portal hypertension stage. 相似文献
95.
Capillary flow studies on bulk molding compound (BMC) using an instrumented injection-molding machine are reported. The significance of extensional flow effects with fiber-reinforced materials is emphasized. The extensional flow behavior in converging dies is modeled, and a means of evaluating both extensional and shear viscosity from capillary flow data is proposed. Methods of correcting results for the effect of deformation heating are discussed. The shear and extensional flow behavior of BMC in the temperature region 18 to 58°C can be fitted to a simplified Arrhenius Law. 相似文献
96.
Brian R. Gibson Erna Storgårds Kristoffer Krogerus Virve Vidgren 《Yeast (Chichester, England)》2013,30(7):255-266
Two distinct genetic groups (Saaz and Frohberg) exist within the hybrid Saccharomyces pastorianus (S. cerevisiae × S. eubayanus) taxon. However, physiological/technological differences that exist between the two groups are not known. Fermentative capability of the parental S. eubayanus has likewise never been studied. Here, 58 lager strains were screened to determine which hybrid group they belonged to, and selected strains were characterized to determine salient characteristics. In 15 °P all‐malt wort fermentations at 22 °C, Frohberg strains showed greater growth and superior fermentation (80% apparent attenuation, 6.5% alcohol by volume in 3–4 days) compared to all other strains and maintained highest viability values (>93%). Fermentation with S. eubayanus was poor at the same temperature (33% apparent attenuation, 2.7% alcohol by volume at 6 days and viability reduced to 75%). Saaz strains and S. eubayanus were the least sensitive to cold (10 °C), though this did not translate to greater fermentation performance. Fermentation with S. eubayanus was poor at 10 °C but equal to or greater than that of the Saaz strains. Performance of Saaz yeast/S. eubayanus was limited by an inability to use wort maltotriose. [14C]‐Maltotriose transport assays also showed negligible activity in these strains (≤0.5 µmol min?1 g?1 dry yeast). Beers from Saaz fermentations were characterized by two‐ to sixfold lower production of the flavour compounds methyl butanol, ethyl acetate and 3‐methylbutyl acetate compared to Frohberg strains. Higher alcohol and ester production by S. eubayanus was similar to that of Frohberg strains. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
97.
C. J. Bettles P. A. Lynch A. W. Stevenson D. Tomus M. A. Gibson K. Wallwork J. Kimpton 《Metallurgical and Materials Transactions A》2011,42(1):100-110
The strain evolution in polycrystalline CP-Ti strip under tension was studied in situ and at two length scales using Synchrotron X-ray diffraction. To establish the bulk material behavior, experiments were performed
at the Australian Synchrotron facility. Because of the relatively large grain size, discontinuous “spotty” Debye ring patterns
were observed, and a peak fitting algorithm was developed to determine the individual spot positions with the necessary precision
for strain determination. The crystallographic directional dependence of strain anisotropy during the loading cycle was determined.
Strain anisotropy and yielding of individual crystallographic planes prior to the macroscopic yield point were further clarified
by in situ loading experiments performed at the Advanced Light Source (ALS). The deviatoric strain accumulation and plastic response
were mapped on a grain-by-grain basis. The onset of microscopic yielding in the grains was identified and correlated with
the relative orientation of the grains with respect to the loading direction. 相似文献
98.
Equal access to mental health services is necessary for healthy individuals and communities. However, due to geographical distances and other barriers, some clients cannot easily access mental health professionals. Technologies such as videoconferencing for clinical purposes (i.e., telemental health) may help to bridge these gaps to connect clients and clinicians at geographically diverse locations. However, despite its potential utility, telemental health has not been widely adopted in Canada. This study is an exploratory investigation into mental health professionals' attitudes toward telemental health, factors that affect the frequency with which they use this technology, and their perceptions of individual characteristics that make clients more or less suitable candidates for telemental health. This study has a particular focus on remote and rural and Operational Stress Injury (OSI) contexts. One hundred sixty mental health workers across Canada participated in an online survey, and 25 mental health workers from Operational Stress Injury clinics across Canada participated in in-person interviews. The data were examined using qualitative and quantitative analysis methods. Findings suggest that mental health workers have overall positive attitudes toward the use of telemental health—particularly for clients in remote and rural locations. Additionally, receiving training in telemental health, being in the mental health field for longer, and perceiving the technology as easy to use are associated with more frequent use of telemental health. Finally, clinicians reported specific client characteristics that they perceive to make some clients unsuitable candidates for telemental health. Implications of these findings and directions for future research are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
99.
Mentoring can have a significant positive impact on the lives of individuals. People with disabilities seeking to locate mentors face a variety of potential challenges and benefits. This article addresses mentoring-related issues faced by professionals with disabilities. The article presents a model of mentoring and discusses the difficulties faced by individuals with disabilities in locating mentors. It describes the negative impact of the lack of available mentors upon the educational and vocational development of people with disabilities. It offers effective strategies aimed at enhancing mentoring relationships with people with disabilities, including macrofocused strategies capable of enhancing the effectiveness of disability-related mentoring programs and microfocused strategies useful in developing quality mentoring relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
This paper measures technological change, factor demand and inter-factor and inter-fuel substitutability measures for China. We use individual fuel price data and a two-stage approach to estimate total factor cost functions and fuel share equations. Both inter-factor and inter-fuel substitution elasticities are calculated and the change in energy intensity is decomposed into its driving forces. The results suggest that energy is substitutable for capital regionally and for labor nationally. Capital substitutes for energy more easily than labor does. Energy intensity changes vary by region but the major drivers seem to be “budget effect” and the adoption of energy-intensive technologies, which might be embodied in high-level energy-using exports and sectors, capital investment and even old technique and equipment imports. Whether the trend in rising energy intensity continues will be significant for China and the rest of the world. 相似文献