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121.
Contact between blood and artificial materials has various effects on blood. Impairment of platelet function is an especially important and well known effect, but its precise mechanism is not clearly understood. The authors constructed a circulation model to investigate the effect of extracorporeal circulation on platelet membrane glycoproteins (GPs), especially GP Ib, and to compare the changes in GP Ib in heparin coated (group C) and nonheparin coated (group N) circuits. As determined by flow cytometry, GP Ib in both groups decreased on initiating circulation, but the decrease in group N was significantly larger than that in group C. There was no observed change in GP IIb/IIIa levels in either group. The extent of shear stress induced platelet aggregation significantly decreased during circulation in both groups. Decreases in the extent of shear stress induced platelet aggregation were significantly less with the use of heparin coated circuits. In addition, the amount of GP Ib in the high speed pellet decreased progressively during circulation in both groups. In contrast, the amount of GP Ib in the Triton insoluble (low speed) pellet increased dramatically during circulation. However, expression of GP Ib in the Triton soluble platelet fraction was low in both groups. From the results, it was concluded that the cause of the decrease in platelet function during extracorporeal circulation is attributable to the internalization of GP Ib from the platelet surface inside the platelet. It also can be said that a heparin coated circuit is one effective means of controlling this change.  相似文献   
122.
IL-15 has recently been detected in the synovium of patients with rheumatoid arthritis. IL-15-activated T cells induce significant TNF-alpha synthesis by macrophages via a cell contact-dependent mechanism, suggesting a key regulatory role for IL-15. Here, we report that the administration of a soluble fragment of IL-15Ralpha into DBA/1 mice, profoundly suppressed the development of collagen-induced arthritis. This was accompanied in vitro by marked reductions in Ag-specific proliferation and IFN-gamma synthesis by spleen cells from treated mice compared with control mice and in vivo by a significant reduction in serum anti-collagen Ab levels. These data directly demonstrate a pivotal role for IL-15 in the development of inflammatory arthritis and also suggest that antagonists to IL-15 may have therapeutic potential in rheumatic diseases.  相似文献   
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130 undergraduates responded to 3 questionnaires over a 6-wk period before and after the 1980 presidential election. The questionnaires assessed self-monitoring tendency, attitudes, and intentions with respect to voting in the election and smoking marihuana, and included self-reports of actual behavior. Low self-monitors tended to exhibit stronger attitude–behavior correlations than high self-monitors. There was, however, no difference in the predictability of intentions from attitudes, a finding that disconfirmed the perceived relevance interpretation of the effect of self-monitoring. Instead, the difference was located in the relation between intentions and behavior; low self-monitors exhibited significantly stronger intention–behavior correlations than did high self-monitors. Findings support the interpretation that the 2 types of individuals are equally aware of the implications of their attitudes, but that high self-monitors, being sensitive to situational demands, are less likely to carry out their previously formed intentions than low self-monitors, who are more attentive to internal cues. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Angiosarcoma of the breast, a rare tumor with very poor prognosis and insidious early manifestations, frequently is far advanced when first detected clinically. The clinical and pathologic changes in two women with primary, unilateral angiosarcoma of the breast are reviewed and the results are compared with 46 cases already published in the literature. Both patients were middle aged with symptoms for approximately 6 months prior to operation. Both frozen section reports were benign and only called malignant on permanent section. Microscopically the tumors were composed of varying sized, tortuous, elongated vascular channels. The operation varied--a modified radical and a simple mastectomy--and both patients are free from disease 4 and 2 years following operation. It is considered that, in view of the proclivity of this tumor for hematogenous metastases, an axillary dissection may not be justified.  相似文献   
130.
We review 97 cases of SMCP, 79 of which were operated. The comparative results are presented. For those requiring surgery (i.e. those having hypernasality), it has been our experience that the use of a pharyngeal flap, alone or combined with a palatoplasty, is productive of better speech results than is a palatoplasty alone.  相似文献   
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