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Np‐Bromophenylmaleimide (BrPMI) does not polymerize in solution by conventional free radical mechanism. However, it readily polymerized in bulk when mixed with a free radical initiator and heated in a microwave oven for 7–8 min. Copolymerization of ethyl methacrylate or butyl methacrylate with BrPMI was conducted in dioxane. The copolymers were characterized by IR and 1H NMR spectroscopy and gel permeation chromatography. The monomer reactivity ratios were calculated by a non‐linear least‐square analysis. Thermal analysis indicated a great improvement in thermal stability of the copolymers compared with the methacrylate homopolymers. BrPMI was also polymerized in bulk in the DSC pan, which allowed the calculation of the activation energy of its polymerization. Copyright © 2003 Society of Chemical Industry  相似文献   
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Minor inflammatory changes are often found in tissues of infants who die suddenly. Recently it has been proposed that these infiltrates signal significant underlying infectious disease and are responsible for death. Currently there is no unanimity about the percentage of cases in which inflammatory infiltrates occur and no international consensus in regard to the minimal criteria required for their diagnosis or their significance. We recommend that the presence of minor inflammatory infiltrates should not detract from the diagnosis of sudden infant death syndrome (SIDS) until further study has determined otherwise.  相似文献   
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OBJECTIVES: Our purpose was to determine those factors affecting the route of delivery decisions and the effect of delivery route on maternal and newborn outcomes with the macrosomic fetus. Do higher cesarean rates result in improved newborn outcomes? STUDY DESIGN: A 10-year (1985 to 1994) retrospective data set was used to analyze patients with newborns weighing > or = 4536 and 4000 to 4535 gm at two Green Bay hospitals. Patients with newborns weighing 2500 to 3999 gm were similarly analyzed for comparison purposes. Individual and obstetrician group cesarean rates and newborn and maternal outcomes were identified. RESULTS: Cesarean birth rates for the fetus weighing > 4000 gm were low and varied from 12.8% in the low obstetrician cesarean rate group to 24.0% in the high group. Higher obstetrician group cesarean rates did not result in improved newborn outcomes. Newborn morbidity and mortality were very low but significantly higher for cesarean birth newborns. Maternal complications were fairly low with cesarean birth and rare after vaginal delivery. CONCLUSION: Patients with a suspected macrosomic fetus should be given the same opportunity to achieve a vaginal delivery as patients with smaller fetuses.  相似文献   
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Ectopic meningioma outside the skull and spinal column is uncommon. We report a cutaneous meningioma of the scalp in a 77-year-old man. A review of types and their management options are discussed. We also highlight that in certain carefully selected cases, these lesions can be treated conservatively.  相似文献   
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The most common chromosomal aberrations in myelodysplastic syndromes (MDS) are complete or partial loss of chromosomes 5 and 7, and trisomy 8. To identify genes important in the pathogenesis of this disease that could be associated with these gross chromosomal defects, we have employed the differential display PCR (DDPCR) procedure developed by Liang and Pardee. This method allows simultaneous comparison of several cDNA sources for the presence of differentially expressed genes. Polymorphonuclear cells (PMNs) from two MDS patients, containing a 5q deletion or a trisomy 8, and three healthy controls were used. Initial screening resulted in the identification of five and three partial cDNA sequences, respectively that were either differentially expressed in both patient samples or in individual patients, as compared with the controls. The authenticity of aberrant expression was verified by reanalyzing the same primer combinations on newly prepared cDNA. Differential expression of the three remaining fragments was subsequently checked on a larger panel of MDS patients, using amplicon-specific primer sets. These were obtained by cloning and sequencing of the fragments. For one partial cDNA (DC3), the original expression pattern, i.e., decreased expression in individual MDS patients, was confirmed. These results demonstrate the utility of the DDPCR procedure to isolate differentially expressed sequences in primary patient samples where the availability of cells is a limiting factor.  相似文献   
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A simple approximate expression is obtained for the motional capacitance of a lateral-field quartz resonator. Comparison with measured values for fundamental-mode and third-overtone SC-cut resonators shows agreement within 10-50%  相似文献   
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