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Background  

It has been observed that ras-transformed cell lines in culture have a higher phosphatidylcholine (PC) biosynthesis rate as well as higher PC-degradation rate (increased PC-turnover) than normal cells. In correspondence to these findings, the concentrations of the PC-degradation product lyso-phosphatidylcholine (LPC) in cancer patients were found to be decreased. Our objective was the systematic investigation of the relationship between LPC and inflammatory and nutritional parameters in cancer patients. Therefore, plasma LPC concentrations were assessed in 59 cancer patients and related to nutritional and inflammatory parameters. To determine LPC in blood plasma we developed and validated a HPTLC method.  相似文献   
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The literature on the occurrence of moderate drinking in ex-alcoholics that has been published since the Rand report in 1976 is reviewed. Although differences in diagnosis, definitions of moderate drinking and length of follow-up make strict comparisons of the studies difficult, the majority of studies seem to indicate that the earlier reports of the frequency of such moderate drinking may be overly optimistic. Depending on the definition of moderate drinking that is used, the longer the interval required for alcoholics to sustain moderate, problem-free drinking, the less likely is such an outcome. Among treated alcoholics, the percentage probably ranges from about 2 to 12%; the percentage may be higher among alcoholics identified in community population samples. Thus far, the only factor common to alcoholics who are able to achieve moderate drinking is their being mild cases (i.e., having fewer lifetime alcohol-related problems than other alcoholics). Factors pertinent in assessing discrepancies between the various studies are discussed.  相似文献   
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Extreme bradycardia during sleep apnea caused by myxedema   总被引:1,自引:0,他引:1  
A 52-year-old man with myxedema was evaluated for anterior chest pain that was considered to be compatible with myocardial ischemia. The night after admission he developed extreme bradycardia, hypotension, and apneic episodes lasting up to 25 s. Continuous positive airway pressure and administration of medroxyprogesterone acetate prevented further episodes and relieved much of the somnolence and lethargy that had contributed to the evidence for myxedema. Alveolar hypoventilation caused by decreased sensitivity to carbon dioxide, inadequate central neural drive, peripheral muscle force, and obesity all may have contributed to the apnea. Chest pain has not recurred, and results of electrocardiography have remained normal following full thyroid hormone replacement. The early recognition of myxedema causing sleep apnea will allow specific treatment to avoid the cardiovascular risks related to prolonged apnea and will help avoid confusion with other etiologies of cardiovascular abnormalities.  相似文献   
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We have used bispecific, cross-linked monoclonal antibodies (heteropolymers, HP) to facilitate rosette formation between human erythrocytes (EH) and dinitrophenylated sheep erythrocytes (DNP-ES) in the absence of complement. The HP contain monoclonal antibodies (mAbs) specific for both the EH C3b receptor (CR1), and the DNP group, and control experiments with homologous competing non-cross-linked mAbs and naive EH and ES confirm the specificity of the rosetting reaction. These results extend our previous studies, of HP-mediated binding of simple protein antigens to EH CR1, to complex particulate antigens and may eventually allow for the targeting and clearance from the circulation of a variety of pathogens associated with infectious disease.  相似文献   
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