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891.
The content of dermal beta‐carotene can be a good indicator showing the body health. Because, it is involved in production of vitamin A maintaining healthy skin and mucous membranes. Also, it reduces the risk of cardiovascular diseases and its antioxidant capacity prevents the formation of cancerous cells. In this work, we use Raman spectroscopy and a low‐cost diffuse reflectance spectroscopy (DRS) to detect the dermal beta‐carotene spectra. We apply computational optical clearing (OC) method to in vivo evaluation the concentration of this chromophore. The results show that Raman spectroscopy is a good tool for in vitro detection of carotenoids but is not able to clearly discriminate the individual carotenoids in skin tissue in vivo. The results also show that using OC enhances the ability of low‐cost diffuse reflection spectroscopy for in vivo detection of dermal beta‐carotene in humans. This method can be used as a low‐cost and portable device to screening the concentration of chromophores such as melanin and carotenoid molecules for oncological studies. 相似文献
892.
Naturally air-aged commercial samples of USP or reagent-grade cholesterol contain components which are mutagenic towards Salmonella typhimurium strains TA1537, TA1538 and TA98. These mutagenic components are associated with the polar cholesterol autoxidation products, but identity of the mutagenic components has not been achieved. Pure crystalline nonmutagenic cholestrol free from autoxidation products becomes mutagenic towards these strains upon heating at 70 degrees in air or following exposure to 60 Co gamma-radiation. 相似文献
893.
Michael Rost Tenzin Wangmo Felix Niggli Karin Hartmann Heinz Hengartner Marc Ansari Pierluigi Brazzola Johannes Rischewski Maja Beck-Popovic Thomas Kühne Bernice S. Elger 《Journal of bioethical inquiry》2017,14(4):555-565
The goal is to present how shared decision-making in paediatric oncology occurs from the viewpoints of parents and physicians. Eight Swiss Pediatric Oncology Group centres participated in this prospective study. The sample comprised a parent and physician of the minor patient (<18 years). Surveys were statistically analysed by comparing physicians’ and parents’ perspectives and by evaluating factors associated with children’s actual involvement. Perspectives of ninety-one parents and twenty physicians were obtained for 151 children. Results indicate that for six aspects of information provision examined, parents’ and physicians’ perceptions differed. Moreover, parents felt that the children were more competent to understand diagnosis and prognosis, assessed the disease of the children as worse, and reported higher satisfaction with decision-making on the part of the children. A patient’s age and gender predicted involvement. Older children and girls were more likely to be involved. In the decision-making process, parents held a less active role than they actually wanted. Physicians should take measures to ensure that provided information is understood correctly. Furthermore, they should work towards creating awareness for systematic differences between parents and physicians with respect to the perception of the child, the disease, and shared decision-making. 相似文献
894.
Todd M. Alam M. Kathleen Alam Muniasamy Neerathilingam David E. Volk S. Sarkar G. A. Shakeel Ansari Bruce A. Luxon 《Metabolomics : Official journal of the Metabolomic Society》2010,6(3):386-394
The industrial application of organophosphates provides the opportunity for environmental exposure. While the toxicity of
organophosphate compounds has been the target of significant work, studies directed towards the identification of metabolite
markers to assess phosphate exposure are more limited. In this study the urine metabolite profiles for rats following single
dose exposure to either tributyl phosphate (TBP, 15 mg/kg body weight) or triphenyl phosphate (TPP, 2 and 20 mg/kg body weight)
were characterized using proton nuclear magnetic resonance (1H NMR) and orthogonal-partial least squares discriminate analysis (O-PLSDA). Using the developed O-PLSDA models it was possible
to clearly identify TBP or TPP exposed animals. The performance of these models was validated using cross validation and permutation
testing. Utilizing the variable importance in projection (VIP) coefficients from the O-PLSDA the metabolites that were most
responsible for the classification of TBP or TPP exposure were determined. This initial study demonstrates the potential for
NMR metabonomic studies for the identification and separation of environmental exposure to organophosphates. 相似文献
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897.
Reactions of cholest-5-ene (I) and its 3 beta-chloro (II) and 3 beta-acetoxy (III) analogs with trimethylchlorosilane-dimethyl sulfoxide in dry acetonitrile furnish cholest-4-en-6 beta-yl methyl sulfide (IV) and its 3 beta-chloro (V) and 3 beta-acetoxy (VI) analogs. Oxidation of (IV) with m-chloroperbenzoic acid affords cholest-4-en-6 beta-yl methyl sulfone (VII) and 4 alpha, 5-epoxy-5 alpha-cholestan-6 beta-yl methyl sulfone (VIII). Under similar reaction conditions, V furnishes 3 beta-chlorocholest-4-en-6 beta-yl methyl sulfone (IX), while VI gives 3 beta-acetoxycholest-4-en-6 beta-yl methyl sulfone (X) and 3 beta-acetoxy-4 alpha, 5-epoxy-5 alpha-cholestan-6 beta-yl methyl sulfone (XI). The structures of these compounds were established on the basis of analytic and spectral data. Some of these compounds have been evaluated for their possible biologic activities. 相似文献
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899.