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991.
Cox Brian J.; Swinson Richard P.; Parker James D. A.; Kuch Klaus; Reichman Jaak T. 《Canadian Metallurgical Quarterly》1993,5(2):235
The Fear Questionnaire responses of 390 patients with panic disorder with agoraphobia were used in a confirmatory factor analysis. The results provide strong support for the 3-factor model of this scale (agoraphobia, social phobia, blood/injury phobia) and the multidimensional model of fears proposed by W. A. Arrindell (1980). The presence of fear clusters other than agoraphobia existing in panic disorder is also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
JE Beem CG Hurley WE Nesbitt DF Croft RG Marks JO Cisar WB Clark 《Canadian Metallurgical Quarterly》1996,11(4):259-265
PURPOSE: The hardness, porosity, and adaptation of removable partial dentures fabricated with one heat-polymerized denture base resin and two resins designed for microwave polymerization were evaluated. MATERIALS AND METHODS: Five prostheses were evaluated for each resin. Adaptation of the denture bases to the master cast was evaluated by spatial orientation and mean weight of residual impression material. The prostheses were than embedded in epoxy resin and sectioned for evaluation of resin hardness (Knoop hardness) and microporosity. RESULTS: There were no significant differences in the adaptation of the acrylic resin bases for Acron MC and Ch Lucitone. There was no significant difference in the mean Knoop hardness values for any of the resin bases near and away from the metal. None of the denture bases showed porosity greater than 100 microns. CONCLUSIONS: Both resin bases formulated for microwave polymerization were effectively polymerized around metal frameworks without adverse effects on resin hardness or porosity. Justi Denture Base material had poorer base adaptation than the other two resins. 相似文献
993.
CM Grilo KN Levy DF Becker WS Edell TH McGlashan 《Canadian Metallurgical Quarterly》1996,47(4):426-429
Structured diagnostic interviews were used to determine DSM-III-R axis I and II diagnoses among 136 female psychiatric inpatients. To distinguish comorbidity of eating disorders with axis I and II disorders from simple diagnostic overlap, the frequency and distribution of diagnoses among the 31 patients with an eating disorder and the 105 without an eating disorder were compared. Social phobia, substance use disorders, borderline personality disorder, and avoidant personality disorder were diagnosed in a significantly larger proportion of the group with eating disorders. Future studies should focus on interpreting the meaning of the co-occurrence of these disorders in patients with eating disorders. 相似文献
994.
HDR/HWR can be one of the major sources of energy for the world in the 21st century because of the size of HDR/HWR resources and the environmental benefits offered by clean HDR/HWR energy. Over the last 25 years, significant advances have been made in the creation and operation of stimulated reservoirs, but little is yet known about the details of joint structure within the body of the reservoir. Continued developments and improvements to the technologies that support HDR/HWR development are essential to increase our understanding of these reservoirs. 相似文献
995.
Peter Shirley Kelvin Sung Erik Brunvand Alan Davis Steven Parker Solomon Boulos 《Computers & Graphics》2008,32(2):260-267
The modern graphics processing units (GPUs), found on almost every personal computer, use the z-buffer algorithm to compute visibility. Ray tracing, an alternative to the z-buffer algorithm, delivers higher visual quality than the z-buffer algorithm but has historically been too slow for interactive use. However, ray tracing has benefited from improvements in computer hardware, and many believe it will replace the z-buffer algorithm as the graphics engine on PCs. If this replacement happens, it will imply fundamental changes in both the API to and capabilities of 3D graphics engines. This paper overviews the backgrounds in z-buffer and ray tracing, presents our case that ray tracing will replace z-buffer in the near future, and discusses the implications for graphics oriented classes should this switch to ray tracing occur. Since computer gaming is one of the most important industry driving graphics hardware and the fact that recently there are many computer science courses related to games and games development, we also describe the potential impact on games related classes. 相似文献
996.
Salicylic acid-induced protein kinase (SIPK) and wounding-induced protein kinase (WIPK), two distinct members of the mitogen-activated protein (MAP) kinase family, are activated in tobacco resisting infection by tobacco mosaic virus (TMV). WIPK activation by TMV depends on the disease-resistance gene N because infection of susceptible tobacco not carrying the N gene failed to activate WIPK. Activation of WIPK required not only posttranslational phosphorylation but also a preceding rise in its mRNA and de novo synthesis of WIPK protein. The induction by TMV of WIPK mRNA and protein also occurred systemically. Its activation at the mRNA, protein, and enzyme levels was independent of salicylic acid. The regulation of WIPK at multiple levels by an N gene-mediated signal(s) suggests that this MAP kinase may be an important component upstream of salicylic acid in the signal-transduction pathway(s) leading to local and systemic resistance to TMV. 相似文献
997.
AE Parker I Van de Weyer MC Laus P Verhasselt WH Luyten 《Canadian Metallurgical Quarterly》1998,273(29):18340-18346
In the fission yeast Schizosaccharomyces pombe the rad17+ gene is required for both the DNA damage-dependent and the DNA replication-dependent cell cycle checkpoints. We have identified a human cDNA homologue of the S. pombe rad17+ checkpoint gene, designated Hrad17. Hrad17 has 49% identity to the S. pombe rad17+ sequence at the DNA level and 49% identity and 72% similarity at the amino acid level. Northern blot analysis indicates elevated levels of expression in testis and in cancer cell lines. Chromosomal localization by fluorescence in situ hybridization indicates that Hrad17 is located on chromosome 4q13.3-21.2. This region is subject to loss of heterozygosity in several human cancers. To begin to understand the protein-protein interactions of the human checkpoint machinery, we have used the yeast two-hybrid system to examine potential interactions between Hrad1, Hrad9, and Hrad17. We demonstrate a physical interaction between Hrad17 and Hrad1 but no interaction with Hrad9. 相似文献
998.
999.
The commenter addresses questions raised in the above-titled paper by K. Suzuki et al. (ibid., vol.39, p.1164-9, May 1992) concerning the validity of bipolar transistor models using the partitioned-charge (PC) approach for transient simulations. Suzuki et al. assert that the concept of charge partitioning applies only to discharge transients and thus the charge-partition ratio depends on the sign of the emitter-base voltage gradient, which, if true, would greatly reduce the utility of PC-based models. The commenter shows that this is not the case and that their conclusion is due only to a misinterpretation of the PC model. The authors reply 相似文献
1000.
SM Todorovic M Prakriya YM Nakashima KR Nilsson M Han CF Zorumski DF Covey CJ Lingle 《Canadian Metallurgical Quarterly》1998,54(5):918-927
A number of steroids seem to have anesthetic effects resulting primarily from their ability to potentiate currents gated by gamma-aminobutyric acidA (GABAA) receptor activation. One such compound is (3alpha,5alpha, 17beta)-3-hydroxyandrostane-17-carbonitrile [(+)-ACN]. We were interested in whether carbonitrile substitution at other ring positions might result in other pharmacological consequences. Here we examine effects of (3beta,5alpha, 17beta)-17-hydroxyestrane-3-carbonitrile [(+)-ECN] on GABAA receptors and Ca2+ channels. In contrast to (+)-ACN, (+)-ECN does not potentiate GABAA-receptor activated currents, nor does it directly gate GABAA-receptor mediated currents. However, both steroids produce an enantioselective reduction of T-type current. (+)-ECN blocked T current with an IC50 value of 0.3 microM with a maximal block of 41%. (+)-ACN produced a partial block of T current (44% maximal block) with an IC50 value of 0.4 microM. Block of T current showed mild use- and voltage-dependence. The (-)-ECN enantiomer was about 33 times less potent than (+)-ECN, with an IC50 value of 10 microM and an amount of maximal block comparable to (+)-ECN. (+)-ECN was less effective at blocking high-voltage-activated Ca2+ current in DRG neurons (IC50 value of 9. 3 microM with maximal block of about 27%) and hippocampal neurons. (+)-ECN (10 microM) had minimal effects on voltage-gated sodium and potassium currents in rat chromaffin cells. The results identify a steroid with no effects on GABAA receptors that produces a partial inhibition of T-type Ca2+ current with reasonably high affinity and selectivity. Further study of steroid actions on T currents may lead to even more selective and potent agents. 相似文献