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Eleven high risk fetuses between 32 and 37 menstrual weeks gestational age were examined by magnetic resonance (MR) imaging. Serial obstetrical sonograms, birth weights, and serial postnatal examinations were obtained in all subjects. Sagittal MR spin echo images obtained using TR = 0.5 sec and TE = 28 msec were useful for assessing subcutaneous fat. Prospective estimates of fetal fat stores correlated with neonatal outcome better than sonographic measurements of fetal growth parameters or actual birth weight. MR appears to be a safe and useful technique that offers information complementary to obstetrical sonography when IUGR is suspected. 相似文献
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Wayman E. Turner Robert H. Hill Jr. W. Harry Hannon John T. Bernert Jr. Edwin M. Kilbourne David D. Bayse 《Archives of environmental contamination and toxicology》1985,14(3):261-271
A bioassay screening procedure was developed using an agar-plate inhibition assay and applied to a set of 32 oil samples obtained during investigations of the toxic-oil syndrome in Spain. After blind-decoding, it was noted that the assay had singled out the case-associated sample as the most toxic oil from the 32-sample set. Five other oil samples were also selected by the assay. Further evaluation showed that these case-associated, suspect case-associated, and miscellaneous oils had significantly more peroxidation than the controls, as indicated by the thiobarbituric acid assay. Products reactive with dinitrophenylhydrazine were present in greater amounts in the assay-selected oils, also indicating larger amounts of aldehydic and ketonic peroxidation products. A volatile peroxidation product, 4-hydroxy-2,3-nonenal (4-hydroxynonenal), was identified and was very toxic to the bioassay screen. The assay-selected oils had significantly greater amounts of this compound. Heating the toxic oils either removed or destroyed the toxic components as revealed by bioassay testing. The 4-hydroxynonenal and other unidentified toxic products were present in the assay-selected oils before heating and absent after heating. Toxic peroxidation products apparently caused the observed response in the assay-selected oils. These findings may indicate that peroxidation, or some type of free radical process, was associated with the toxicity of these oils to humans. The bioassay procedure should be applied to a larger set of epidemiologically documented oils to determine if this screening process can contribute to a better understanding of the toxic-oil syndrome. 相似文献
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丹酚酸A对大鼠半乳糖性白内障形成的抑制作用 总被引:20,自引:0,他引:20
业已证明,丹酚酸A有较强的抗氧化和清除自由基等多方面的作用。本实验用大鼠半乳糖性白内障模型,研究局部应用丹酚酸A对白内障形成的影响。结果表明,局部用0.05%的丹酚酸A(每日滴眼两次)对白内障的形成有一定的抑制作用,使白内障形成过程减缓。而且给药组动物晶体内过氧化氢和脂质过氧化产物(MDA)含量减少,蛋白巯基和总巯基增加。体外实验表明,丹酚酸A对醛糖还原酶有一定抑制作用。以上结果提示,丹酚酸A可通过不同途径抑制白内障的形成,对糖性白内障的防治有一定意义。 相似文献
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Florian Heinen Guy Molenaers Charlie Fairhurst Lucinda J. Carr Kaat Desloovere Emmanuelle Chaleat Valayer Edith Morel Antigone S. Papavassiliou Kristina Tedroff S. Ignacio Pascual-Pascual Günther Bernert Steffen Berweck Guiseppe Di Rosa Elisabeth Kolanowski Ingeborg Krgeloh-Mann 《European journal of paediatric neurology》2006,10(5-6):215-225
An interdisciplinary group of experienced botulinum toxin users and experts in the field of movement disorders was assembled, to develop a consensus on best practice for the treatment of cerebral palsy using a problem-orientated approach to integrate theories and methods. The authors tabulated the supporting evidence to produce a condensed but comprehensive information base, pooling data and experience from nine European countries, 13 institutions and more than 5500 patients. The consensus table summarises the current understanding regarding botulinum toxin treatment options in children with CP. 相似文献
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Carotid back pressures in conjunction with cerebral angiography 总被引:1,自引:0,他引:1