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Immunobiology of human gliomas   总被引:5,自引:0,他引:5  
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mRNA for the suppressive epitope of p15E was found to be present in 24 of 30 samples of human colorectal cancer and in all four specimens of gastric cancer. mRNA for p15E was seldom seen in nonmalignant colonic or gastric mucosa but, when present, was associated with inflammatory or pre-malignant conditions of the digestive tract. Synthetic peptides derived from the conserved p15E sequence were found to suppress some aspects of the immune response implicated in anti-tumour activity. These data suggest that a p15E-related material with immunomodulatory properties is elaborated within human tumours, either by the tumour itself or as a normal component of the endogenous anti-tumour reaction.  相似文献   
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Agonist-evoked rises in [Ca2+]i were recorded from single bovine aortic endothelial cells in the middle of confluent monolayers by dual-wavelength microspectrofluorimetry. Low doses of ATP (1-5 microM) induced a transient rise in [Ca2+]i followed by a maintained plateau phase upon which were superimposed irregular fluctuations in [Ca2+]i. The mechanism underlying these fluctuations is not known. Addition of the phorbol ester, phorbol 12-myristate 13-acetate (PMA), to single cells displaying ATP-induced fluctuations reduced the amplitude and frequency of these fluctuations but the maintained plateau phase was unaffected. Elevation of intracellular cAMP by activation of adenylate cyclase with forskolin, or application of dibutyryl cAMP did not affect the ATP-induced fluctuations. These results suggest a possible role for the diacylglycerol limb of the phosphoinositide hydrolysis pathway, via activation of protein kinase C, but not cAMP, in the mechanism responsible for generating ATP-induced fluctuations in [Ca2+]i.  相似文献   
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ABSTRACT: This study obtained input from Australian student smokers approximately 15 years old, which may be useful in designing school-based smoking cessation programs. The sample was analyzed by previous quitting experience and intentions to quit. The order of preference for assistance options and incentives for quitting was similar across all groups: however, those who previously attempted to quit (previous quitters) and those who intended to quit (intenders) in the future were significantly more likely than non-quitters and non-intenders to find assistance options for quitting acceptable. The potential for saving money emerged as an important variable in convincing all groups of smokers not to smoke, and using personal willpower and cutting down slowly were identified as important in actual attempts to quit. The need for programs to be free and for friends to be supportive also was evident across all groups.  相似文献   
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Book Reviews     
Book reviews in this article:
Biopsy Pathology of Melanocytic Disorders . W.J. M oor and T. K rausz (1992).
Topical Corticosteroids . Edited by H.I.M aibach and C.S urber (1992).  相似文献   
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OBJECTIVE: We performed a prospective, randomized clinical trial to compare the usefulness of the minute ventilation test (MVT) with clinical judgement in predicting readiness for extubation in preterm newborns with respiratory distress syndrome requiring surfactant therapy and mechanical ventilation. STUDY DESIGN: A total of 42 preterm infants with respiratory distress syndrome were randomized when they reached preselected ventilator settings. The primary outcome measure was the time from study entry to extubation, provided the infant remained extubated for at least 24 hours. RESULTS: Infants evaluated by the MVT were extubated in a significantly shorter period of time (mean of 8 hours) than those evaluated clinically (mean of 36 hours). The extubation failure rate was similar in the two groups. CONCLUSION: The MVT is an easily performed objective measure that can be used to predict readiness for extubation in preterm infants. In this study, it significantly shortened the time for extubation and was not associated with a higher rate of reintubation.  相似文献   
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