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Non-tuberculous mycobacterium (NTM) lung disease is increasing in prevalence. We analyzed the frequency of NTM lung disease among patients who are suspected of tuberculosis. NTM was isolated from about one-fourth of the mycobacterium culture-positive patients and about half of these had NTM lung disease. Therefore, NTM isolates should be routinely identified at the species level for adequate treatment.  相似文献   
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The binding of chlorpromazine · HCl at the human erythrocyte surface has been detected through its effect on cellular electrophoretic mobility. Incubation of erythrocytes (approx. 5 · 106/ml) in 23 μM chlorpromazine · HCl resulted in a reduction of negative electrophoretic mobility from the control value of ?1.11 ± 0.01 (μm · s?1)/(V · cm?1) to ?1.00 ± 0.02 (μm · s?1)/(V · cm?1) (pH 7.2, ionic strength 0.155). This mobility change was completely reversed when chlorpromazine · HCl was removed by centrifugal washing. Increasing the drug concentration to 70μM did not affect the mobility change, indicating saturation of the electrophoretically detectable drug binding sites over chlorpromazine · HCl concentration range studied here. The effect of the 23 μM chlorpromazine · HCl on electrophoretic mobility was also measured in isotonic media of reduced ionic strength. The drug-induced reduction in negative surface charge density was found to be independent of ionic strength over the range 0.155 (Debye length, 0.8 nm) to 0.00310 (Debye length, 5.7 nm).Fixation of erythrocytes with glutaraldehyde affected neither the normal electrophoretic mobility of discocytes nor the reduced electrophoretic mobility of chlorpromazine · HCl-induced stomatocytes. When these stomatocytes were first fixed with glutaraldehyde, then washed free of chlorpromazine · HCl, they retained the stomatocyte form while regaining a normal control electrophoretic mobility. Conversely, when discocytes fixed in that form were treated with chlorpromazine · HCl, they showed the same mobility change as did fixed or unfixed stomatocytes. The drug-induced mobility change is therefore independent of the shape change, but reflects a contribution to cellular surface charge density from the membrane-bound chlorpromazine · HCl molecules. From the charge reduction, it is estimated that about 106 chlorpromazine · HCl molecules are bound at the electrokinetic cell surface and occupy approximately 0.4% of the total surface area.  相似文献   
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The details of the deliveries of 10 infants whose cords were clamped before the onset of respiration and within one minute of delivery of the chin but whose residual placental volumes were unexpectedly low are compared with 20 control infants whose cords were clamped under similar conditions but who had the expected residual placental volumes. The only statistically significant difference between these groups was in the high number of patients with foetal distress and low Apgar scores in the former group. It is concluded that placental transfusion occurred before delivery in these patients and that foetal asphyxia facilitated this transfusion, which may be the underlying mechanism of neonatal erythrocythaemia or transient tachypnoea of the newborn.  相似文献   
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Pathogen detection using DNA microarrays has the potential to become a fast and comprehensive diagnostics tool. However, since pathogen detection chips currently utilize random primers rather than specific primers for the RT-PCR step, bias inherent in random PCR amplification becomes a serious problem that causes large inaccuracies in hybridization signals.  相似文献   
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