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Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.  相似文献   
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Summary To evaluate the influence of the stomach and the cholinergic system on gallbladder contraction induced by physiological stimuli, the reduction in gallbladder volume in 7 healthy volunteers has been studied by real-time ultrasonography after the oral and intraduodenal administration of olive oil, preceded by pretreatment with cimetropium bromide or placebo. After an overnight fast, each subject swallowed 50 ml olive oil or it was administered through a naso-duodenal tube in the proximal duodenum. Cimetropium bromide 5 mg or placebo was given intravenously under double-blind control.After the placebo pretreatment, gallbladder contraction was greater and faster after intraduodenal oil than after oral oil. Cimetropium bromide decreased the extent, velocity and duration of gallbladder contraction induced by intraduodenal olive oil but it only reduced the velocity of the contraction induced by oil given orally.It is concluded that in normal human subjects the stomach modulates the extent and velocity of postprandial gallbladder contraction and that anticholinergic agents antagonize the gastric and duodenal phases of the response of the gallbladder to a meal.  相似文献   
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Inactivation of mouse C3H 10T1/2 cells in plateau-phase (7.8 x 10(4) cells/cm2) was studied by using alpha-particles from the irradiation facility installed for radiobiological experiments at the 3 MV Tandem accelerator, University of Naples. Silicon detectors and CR39 plastic track detectors were employed for dosimetric purposes. The cells were exposed to high LET monoenergetic alpha-particles (energy of 1.8 MeV at the centre of the cell nucleus, track-averaged LET of 177 keV/micron and dose-rate of 1.1 Gy/min) and low-LET 80 kVp X-rays. The X-ray survival curve showed a significant shoulder (alpha/beta = 9 Gy) while the survival curve for alpha-particles was close to exponential. The mean lethal dose of alpha-particles was 0.77 +/- 0.02 Gy and the RBE was 5.2 at 80% survival and 3.0 at 5% survival. Survival of exponentially growing cells (2 x 10(4) cells/cm2) following irradiation with the alpha-particle beam is also reported. The nuclear areas of 10T1/2 cells were measured as 299 +/- 9 micron 2 and 250 +/- 8 micron 2 for cells in log phase and plateau phase, respectively. The inactivation cross-section, obtained from the mean lethal dose, was 34 micron 2 and 37 micron 2 for cells in log phase and plateau phase, respectively. These values appear to be the maximum measured values for the inactivation cross-section of 10T1/2 cells as a function of the alpha-particle LET. This saturation cross-section is very similar to the saturation values reported in the literature for other mammalian cell lines.  相似文献   
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The 5-HT1 agonist sumatriptan (SUM) elicits an increase in amplitude of oesophageal motor waves and of lower oesophageal sphincter (LOS) tone in healthy subjects. The aim of the study was to evaluate whether such an effect occurs also in patients with ineffective oesophageal motility (IOM). 16 patients (nine males and seven females, age range 34-55 years) with chest pain and mild to moderate dysphagia were studied; all had undergone previous cardiologic, radiologic and upper gastrointestinal endoscopic exams that were normal. An oesophageal manometry was performed using an electronic probe to record swallows, oesophageal, LOS and gastric motility. The patients whose motor pattern were compatible with IOM (>30% of motor waves with amplitude <30 mmHg and/or non-transmitted) received SUM or placebo 6 mg s.c., injected in the morning and in the afternoon in a random order. The data analysis was limited to 1 h before and 1 h after the drug injections. Ten out of the 16 patients showed an IOM motor pattern. The administration of SUM caused a significant increase in the number of swallows (SUM 99.5 +/- 15.4 vs 78.6 +/- 16.1 basal, P = 0.03) and of primary oesophageal motor waves (SUM 89.6 +/- 13.4 vs 67.2 +/- 12.9 basal, P = 0.04) with no significant changes in the percentage of swallows associated with propagation. Placebo was not associated with increase in the number of swallows (80.3 +/- 14.6, P = 0.9) or of primary oesophageal motor waves (70.1 +/- 12.3, P = 0.7). The amplitude and the percentage of propagated oesophageal motor waves as well as the mean basal LOS tone were unaltered by SUM. There was no change in the symptoms reported after SUM. Although effective in healthy subjects, SUM 6 mg s.c. improves only the numbers but not the amplitude or propagation of oesophageal motility of patients with IOM. The 5-HT1 pathway and its acute stimulation seem to play only a minor role in the pathogenesis of such a disease.  相似文献   
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Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.  相似文献   
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