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We recommend routine fluorescein examination whenever a major flap is manipulated. It will depict those flaps which are dead at elevation, and it will allow us to critically evaluate the other factors which might have affected flap viability. The examination is safe when precautionary measures are taken. 相似文献
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(+/-)-N-(n-propyl) amphetamine (I), a secondary amine, was readily metabolized by Cumminghamella echinulata. The products included known C- and N-oxygenated mammalian metabolites as well as N-acetylamphetamine and were identified by gas chromatography and mass spectrometry. 相似文献
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Circumcision is often claimed to be simpler, safer and more cost-effective when performed in the neonatal period as opposed to later in life, with a greater benefit-to-risk ratio. In the first part of this paper, we critically examine the evidence base for these claims, and find that it is not as robust as is commonly assumed. In the second part, we demonstrate that, even if one simply grants these claims for the sake of argument, it still does not follow that neonatal circumcision is ethically permissible absent urgent medical necessity. Based on a careful consideration of the relevant evidence, arguments and counterarguments, we conclude that medically unnecessary penile circumcision—like other medically unnecessary genital procedures, such as ‘cosmetic’ labiaplasty—should not be performed on individuals who are too young (or otherwise unable) to provide meaningful consent to the procedure. 相似文献
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Previous studies by other investigators have established that L-region methyl derivatives of dibenz[a,h]anthracene (DBA) were more carcinogenic than the parent hydrocarbon. The bioalkylation of DBA was investigated by incubating the hydrocarbon with rat liver cytosol fortified with S-adenosyl-L-methionine (SAM) in 0.1 M phosphate buffer (pH 7.4) for 1 h at 37 degrees C in air. The reaction was stopped by the addition of cold acetone and the mixture extracted with ethyl acetate and washed with water. The organic phase was evaporated and the residue dissolved in methylene chloride for analysis by reverse phase high performance liquid chromatography (HPLC) and gas chromatography/mass spectroscopy GC/MS. Products were found that were indistinguishable from 7-methyl-DBA and 7,14-dimethyl-DBA, 7-hydroxymethyl-DBA, 7-hydroxymethyl-14-methyl-DBA, and 7,14-dihydroxymethyl-DBA. The results suggest that unsubstituted carcinogenic hydrocarbons are preprocarcinogens that react with SAM in liver cytosol preparations, to form alkyl substituted procarcinogens, which are more potent than the corresponding preprocarcinogens. 相似文献
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Corrections to: Apparent recruitment failure for the vast majority of coral species at Eilat,Red Sea
Guerrini Gabriele Yerushalmy Maayan Shefy Dor Shashar Nadav Rinkevich Baruch 《Coral reefs (Online)》2021,40(4):1393-1395
Coral Reefs - A correction to this paper has been published: https://doi.org/10.1007/s00338-021-02121-x 相似文献