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991.
PV LoGrasso J Hawkins LJ Frank D Wisniewski A Marcy 《Canadian Metallurgical Quarterly》1996,93(22):12165-12170
There is a growing body of evidence, including data from human genetic and T-cell receptor function studies, which implicate a zeta-associated protein of M(r) 70,000 (Zap-70) as a critical protein tyrosine kinase in T-cell activation and development. During T-cell activation, Zap-70 becomes associated via its src homology type 2 (SH2) domains with tyrosine-phosphorylated immune-receptor tyrosine activating motif (ITAM) sequences in the cytoplasmic zeta chain of the T-cell receptor. An intriguing conundrum is how Zap-70 is catalytically activated for downstream phosphorylation events. To address this question, we have used purified Zap-70, tyrosine phosphorylated glutathione S-transferase (GST)-Zeta, and GST-Zeta-1 cytoplasmic domains, and various forms of ITAM-containing peptides to see what effect binding of zeta had upon Zap-70 tyrosine kinase activity. The catalytic activity of Zap-70 with respect to autophosphorylation increased approximately 5-fold in the presence of 125 nM phosphorylated GST-Zeta or GST-Zeta-1 cytoplasmic domain. A 20-fold activity increase was observed for phosphorylation of an exogenous substrate. Both activity increases showed a GST-Zeta concentration dependence. The increase in activity was not produced with nonphosphorylated GST-Zeta, phosphorylated zeta, or phosphorylated ITAM-containing peptides. The increase in Zap-70 activity was SH2 mediated and was inhibited by phenylphosphate, Zap-70 SH2, and an antibody specific for Zap-70 SH2 domains. Since GST-Zeta and GST-Zeta-1 exist as dimers, the data suggest Zap-70 is activated upon binding a dimeric form of phosphorylated zeta and not by peptide fragments containing a single phosphorylated ITAM. Taken together, these data indicate that the catalytic activity of Zap-70 is most likely activated by a trans-phosphorylation mechanism. 相似文献
992.
Frank Di Marzio 《Computer Physics Communications》2002,143(3):241-256
993.
Memorializes Sigmund Koch. Although dismissive of grand systems, on both principled and empirical grounds, Koch indicated ways in which psychologists can realize the kind of sensibility-based, context-dependent, finely textured insights that can result from authentic probing of human experience. His own inquiries into a perceptual theory of definition, the nature of objective value-properties, and the processes of creative activity in the arts illustrate the sort of qualitative, philosophically informed, and empirically grounded investigations that should be central to what he christened "the psychological studies." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
995.
Johnson Jeffrey G.; Spitzer Robert L.; Williams Janet B. W.; Kroenke Kurt; Linzer Mark; Brody David; deGruy Frank; Hahn Steven 《Canadian Metallurgical Quarterly》1995,63(1):133
The psychiatric comorbidity, health, and functioning of primary care patients with alcohol abuse and dependence (AAD) was investigated in a sample of 1,000 patients. Psychiatric symptomatology was assessed with the Primary Care Evaluation of Mental Disorders (PRIME-MD) diagnostic system. Health and functional status was assessed with the Medical Outcomes Study Short Form General Health Survey (SF-20). Results indicated that use of the PRIME-MD system brought about a 71% increase in physician recognition of AAD. AAD patients were diagnosed with substantial psychiatric comorbidity, and they reported poorer health and functioning than did patients without any psychiatric disorders. However, they reported less impairment and psychiatric comorbidity than did patients with other psychiatric disorders. Results also indicated that AAD patients' health and functioning were associated with the presence or absence of psychiatric comorbidity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Frank B. Cross 《Reliability Engineering & System Safety》1998,59(1):27-40
Risk, as commonly understood, is a complex melange of facts, values, and fears. While this complexity of public risk perception is now broadly recognized, its implications are insufficiently explored. Public risk perceptions offer p poor guide for public policymaking. Popular assessments of risk are tainted by misinformation and unreliable heuristics. While subjective considerations, often called values, play a role in public perception of risk, those ‘values’ are often inappropriate for government decisionmaking. Reliance on public perceptions of risk means more premature deaths. Public risk perception also is systematically skewed contrary to the interests of the disadvantaged. Strict probabilistic risk measures generally provide a superior guide for government regulatory policy. 相似文献
997.
998.
Hoyt William T.; Fincham Frank D.; McCullough Michael E.; Maio Gregory; Davila Joanne 《Canadian Metallurgical Quarterly》2005,89(3):375
Social relations analyses examined the relative importance of forgivingness (disposition to forgive others), forgivability (tendency to obtain forgiveness from others), and relationship effects in determining family members' transgression-related interpersonal motivations (TRIMs) and their perceptions of others' TRIMs toward them (PTRIMs). In 2 studies, the individual and dyadic predictors of these components and their relative importance differed by family role (father, mother, or early adolescent child). Dispositional tendencies accounted for the most variance in father and child forgiveness, whereas mothers' TRIMs and PTRIMs were more strongly determined by relationship and partner effects. Personality correlates of forgivingness and forgivability were moderated by family role. The findings point to the need to embed the study of forgiveness in more complex psychosocial contexts. The theoretical, methodological, and applied implications of this conclusion are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Lateral motion of magnetic tape is investigated on roller and porous air-bearing type tape drives. The lateral tape motion signal is high-pass filtered and the spectral components are analyzed. Time-frequency analysis is also performed. The effect of dynamic tension changes during high frequency lateral motion events is examined, and the tension difference across the tape head is found to be correlated to the lateral motion of tape near the head. The effect of lateral motion of tape on tape pack winding is investigated and the frequencies observed during edge contact are analyzed. 相似文献
1000.