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121.
PH Wooley C Schaefer JD Whalen JA Dutcher DF Counts 《Canadian Metallurgical Quarterly》1997,24(5):890-898
OBJECTIVE: Platelet factor 4 (PF-4) is a critical alpha chemokine in inflammation and injury responses, with multiple effects upon cellular activities. Discrete peptide sequences of the PF-4 molecule have been shown to retain biological activity. Our aim was to examine the influence of the PF-4 derived octapeptide (CT-112; TTSQVRPR) on type II collagen induced arthritis in mice, to determine if this peptide exhibited antiinflammatory properties. METHODS: DBA/1 mice were treated with CT-112 from either the time of immunization with type II collagen or from the initial onset of arthritis. RESULTS: CT-112 both prevented the development of arthritis in mice treated prophylactically and reduced progression of disease in animals treated therapeutically, and was active when delivered by either subcutaneous injection or oral gavage. No marked immunosuppressive effects were observed during CT-112 treatment, with only moderate decrease in antibody levels and mitogen responses. A significant reduction of the circulating levels of IL-1 was a consistent finding in mice treated therapeutically with CT-112. CONCLUSION: These data suggest PF-4 derived octapeptide exerts antiinflammatory effects of experimental arthritis in mice. 相似文献
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Oxygen mass transfer calculations in large arteries 总被引:1,自引:0,他引:1
Parkinsonism is characterised by overactive glutamatergic transmission in the cortico-striatal and subthalamo-medial pallidal pathways. Local blockade of glutamatergic transmission in these pathways can alleviate parkinsonian symptoms. The effectiveness of the treatment, however, is often limited by the simultaneous appearance of unwanted side-effects. These side-effects, including ataxia and dissociative anaesthesia, are particularly problematic when N-methyl-D-aspartate (NMDA) antagonists are used. In an attempt to overcome these problems we have attempted to manipulate excitatory amino acid (EAA)-mediated neurotransmission indirectly by targeting the NMDA receptor associated modulatory sites. We review evidence which demonstrates that antagonists for both the NMDA associated glycine and polyamine sites can reverse parkinsonian symptoms when injected intra-cerebrally in both MPTP-treated and bilateral 6-OHDA lesioned marmosets without eliciting unwanted side-effects. We further review preliminary data which suggest that ifenprodil, a polyamine site antagonist, has striking anti-parkinsonian actions in the marmoset. Potential mechanisms of action underlying these effects are discussed in terms of NMDA receptor subtypes and the neuroanatomical locus of action. The anti-parkinsonian efficacy of intra-striatally administered EAA antagonists leads us to question the view of dopamine acting in the striatum as a simple neuromodulator. 相似文献
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OBJECTIVE: The relationship between intentions to use alcohol and risk factors was examined among fifth and sixth graders. METHOD: Subjects completed a questionnaire that assessed intentions to use alcohol and eight risk factors. Risk factors included peer and parental use and attitudes toward use, sensation seeking, tolerance of deviance, rejection of parental authority, and family cohesion. RESULTS: Multivariate analyses showed that the risk factors were able to discriminate between those who intended to use alcohol and those who did not. Family factors showed stronger relationships to intentions among fifth graders, and peer factors were more strongly related to intentions among sixth graders. CONCLUSIONS: Risk factors can be used to target preadolescents who may be at risk for early alcohol use, and programs that attempt to prevent early initiation of alcohol use among adolescents can be designed. 相似文献
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The purpose of this study was to investigate self-disclosure, emotion-focused, and problem-focused coping styles among men with borderline hypertension and two groups of normotensive men differentiated by parental hypertension. Because blood pressure reactivity may discriminate between hypertensive and normotensive men, subjects in these three groups were categorized as high or low cardiovascular reactors based on their blood pressure response to a mental arithmetic task. Self-disclosure and coping styles were investigated in relation to status effects within the doctor-patient relationship. Men with exaggerated blood pressure reactivity were less self-disclosive and used fewer emotion-focused coping strategies than men with no blood pressure reactivity. Normotensives with a history of parental hypertension were less self-disclosive than normotensives without a history of parental hypertension. 相似文献