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David L. Becton Henry S. Friedman Joanne Kurtzberg Sara Chaffee John M. Falletta Thomas R. Kinney 《Pediatric hematology and oncology》1986,3(3):259-265
Mycoplasma pneumoniae, which usually causes mild infections in normal children, has been shown to cause isolated cases of severe pneumonia in children with sickle cell disease. We recently observed an outbreak of Mycoplasma pneumonia in three sisters with homozygous sickle cell disease. Two of them required hospitalization, and one progressed to respiratory failure requiring prolonged ventilatory assistance. All eventually recovered without long-term pulmonary complications. Familial outbreaks are not uncommon in Mycoplasma infection, but they have not been described previously in siblings with sickle cell disease. It is assumed that local or systemic host defense abnormalities predispose patients with sickling syndromes to more severe courses of Mycoplasma infections. 相似文献
93.
WM HUI J HO BW CHEN C-H CHO FJ BRANICKI SK LAM 《Journal of gastroenterology and hepatology》1997,12(1):7-12
We compared the effects of misoprostol, omeprazole and methylcellulose (control) on gastric mucosal injury induced by nicotine and/or ethanol. The results demonstrate that misoprostol and omeprazole each significantly reduce macroscopic injury and deep injury at a microscopic level (P < 0.05) induced by nicotine alone, ethanol alone or a combination of ethanol and nicotine. Misoprostol and omeprazole each reduced the leakage of fluorescein isothiocyanate-albumin into the interstitium in the gastric mucosa. Misoprostol and omeprazole are each effective in preventing injury induced by nicotine and ethanol and vascular factors are involved. 相似文献
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辽西蜂胶中一新的桂皮酸酯成分的分离与鉴定 总被引:1,自引:0,他引:1
A new cinnamate ester drivitive (II) and three flavonoids (I, III, IV) were isolated from Liaoxi propolis. Their chemical structures were established as benzyl caffeate (II), 7-O-methylchrysin (I), genkwanin (III) and rhamnazin (IV) by spectral analysis. II is a new natural compound; I, III and IV were found from the propolis for the first time. 相似文献
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Three patients with histologically confirmed sarcoidosis with spinal cord involvement were examined with high-field-strength magnetic resonance imaging (1.5 T) before and after the administration of gadolinium diethylenetriaminepentaacetic acid. In addition to intramedullary expansion, areas of patchy, multifocal, parenchymal enhancement and areas of linear peripheral enhancement were seen in all three patients; these findings have not been previously reported and are unusual for other more common spinal cord lesions. This observation led to a correct diagnosis and a limitation of the extent of biopsy in two of the cases. Unfortunately, this enhancement pattern is not specific for sarcoidosis, as the authors have observed similar findings in two cases of biopsy-proved myelitis and multiple sclerosis. The peripheral enhancement is thought to be located in the leptomeninges due to leptomeningeal involvement, which was proved histologically in one case. This pattern of involvement, while not specific, is certainly consistent with and, in the appropriate clinical setting, highly suggestive of sarcoidosis. 相似文献
98.
Behnoush Rashedi DMD MS Donald A. Tyndall MPH DDS PhD John B. Ludlow DDS MS Nancy R. Chaffee DDS MS Albert D. Guckes DDS MS 《Journal of prosthodontics》2003,12(3):176-186
PURPOSE: This study was designed to optimize a new radiographic modality known as tuned aperture computed tomography (TACT) for cross-sectional imaging of implant sites in human dry mandibles. MATERIALS AND METHODS: Five imaging modalities were compared for image quality and measurement accuracy: (1) conventional hypocycloidal tomograms, (2) TACT images reconstructed using the average method produced using a linear x-ray source movement, (3) TACT images reconstructed using the average method produced using a multidirectional x-ray source movement, (4) minimally reconstructed TACT images without a fiducial marker at the site of interest, and (5) minimally reconstructed TACT images with a fiducial marker at the site of interest. RESULTS: The extended Mantel-Haenszel mean score statistic was used to investigate the influence of modality on subjective image quality. A statistically significant difference for certain types of TACT images and multidirectional tomography (P < 0.0001) was observed. Linear TACT and multmin TACT were rated as significantly better than other image modalities (P < 0.0009), whereas multidirectional tomography was rated as being significantly worse than other radiographic modalities (P < 0.0001). For the quantitative assessment, data were normalized and analyzed statistically through a paired-comparisons t test. For each modality, the accuracy for maximum height and height was significantly different from ground truth (P < 0.05). CONCLUSION: The qualitative data suggest that visibility of structures important to the choice of implant location and dimension were seen better with certain TACT methods. Quantitative differences from ground truth (actual measurements of the bone-absolute truth) were clinically negligible. TACT appears to offer the potential of superior image quality over the status quo. 相似文献
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