Nitrosamines
Mostrando 1-12 de 35 artigos, teses e dissertações.
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1. Development of analyrtical methods for determination of N-nitrosamines in shampoo samples by liquid chromatography coupled to diode array, electrochemical and mass spectrometry detecto / Desenvolvimento de métodos para determinação de N-nitrosaminas em amostras de xampu por cromatografia líquida acoplada à detecção por arranjo de diodos, eletroquímica e espectrometria de massas
N-nitrosamines (NA) are N-nitroso compounds, showed to be carcinogenic in a wide variety of experimental animals. In addition, they also present mutagenic and teratogenic activities. N-nitrosamines have been found during the last three decades in a variety of consumer products, including cosmetic and personal care products, and their raw materials. The most
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 21/02/2011
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2. Contaminação de produtos de higiene e cosméticos por n-nitrosaminas
N-nitrosamines are carcinogenic compounds that have been found during the last three decades in a variety of consumer products, including cosmetic and personal care products, and their raw materials. These compounds are formed from amine precursors and nitrosating agents present in the formulations. This paper reviews the formation and occurrence of N-nitros
Química Nova. Publicado em: 2009
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3. Avaliação e critérios de eficiência nos processos de tratamento de fluido de corte por eletroflotação / Evaluation criteri and efficiency in the procedures for treatment of fluid cutting by eletroflotation
In the machining process cutting fluids are used to facilitate the manufacture of metal parts, which has resulted in problems of various orders, ranging from the generation of harmful effects on the desktop to the aggression of the environment with their improper disposal. The cutting fluids are composed of oils and minerals, synthetic solutions and water, c
Publicado em: 2008
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4. CYP2A6 and CYP2E1 polymorphisms in a Brazilian population living in Rio de Janeiro
Cytochrome P450 (CYP) is a superfamily of enzymes involved in the metabolism of endogenous compounds and xenobiotics. CYP2A6 catalyzes the oxidation of nicotine and the activation of carcinogens such as aflatoxin B1 and nitrosamines. CYP2E1 metabolizes ethanol and other low-molecular weight compounds and can also activate nitrosamines. The CYP2A6 and CYP2E1
Brazilian Journal of Medical and Biological Research. Publicado em: 2006-02
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5. Determination of N-nitrosamines and N-nitrosables substances in rubber teats and sothers by GC-TEA
N-Nitrosamines are receiving special attention because they present high mutagenic and carcinogenic potential. They can be found in several areas. In rubber, for example, they can be found in Nipples and Pacifiers. Spiegelhalder and Pressumann, have observed that N-Nitrosamines present in nipples and pacifiers could easily migrate to artificial saliva. They
Brazilian Archives of Biology and Technology. Publicado em: 2006-01
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6. Determinação de nitrosaminas volateis em salsichas "hot dog". / Determination of volatile nitromines in hot-dog sausage.
During the curing process, nitrite and nitrate are the principal ingridients udes for curing. They confer and colored color characteristic of the cured meat as sausage, and act as antioxidants and antimicrobial, comtrolling the growth of Clostridium botulinum. The most important toxic effect of the presence of nitrate and nitrite is the formation of nitrosam
Publicado em: 2006
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7. Fatores de risco para cancer de estomago: avaliação dos teores de nitrato e nitrito em linguiças
A dieta alimentar rica em nitrato e nitrito pode estar associada com cancer de estomago. Nitrato e nitrito são aditivos quimicos utilizados como conservantes, principalmente em produtos cárneos curados, com a finalidade de inibir o crescimento do Clostridium botulinum, produtor da toxina que causa botulismo. A presença desses aditivos nos alimentos é pre
Publicado em: 2006
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8. Desenvolvimento de metodos analiticos para determinação de nitrato, nitrito e n-nitrosaminas em produtos carneos
Nitrosamines are N-nitroso compounds formed in certain foods by the reaction of a nitrosating agent, derived from either nitrite salts or nitrogen oxide, with a substance having an amino group. The majority of nitrosamines tested in animals are carcinogenic, mutagenic, teratogenic and act transplacentally. This work describes analytical methods for the deter
Publicado em: 2004
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9. Pré-concentração de nitrosaminas a partir de amostras aquosas por extração em fase sólida e cromatografia capilar eletrocinética micelar
This paper describes the development of a methodology for solid phase extraction (SPE) and pre-concentration of nitrosamines from aqueous samples using granular activated charcoal as stationary phase. micelar electrokinetic capillary Chromatography (MEKC) was used for the separation and identification of the nitrosamines in the extracts. Using a sample with
Química Nova. Publicado em: 2003-03
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10. Microbiota in chagasic megaesophagus / Microbiota no megaesôfago chagásico.
The stasis of saliva and swallowed food in the esophageal lumen of patients with chagasic megaesophagus causes: (1) bacterial overgrowth in the esophageal lumen, (2) recurring pulmonary aspirations and respiratory infections, (3) increased risk of surgical or endoscopic procedures if perforation occurs by the major possibility of contamination, and (4) the d
Publicado em: 2001
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11. Oxidações bio e fotosensibilizadas por oxigenio singlete : consequencias em sistemas quimicos e bioquimicos
Our experiments show that an effective procedure for verifying the presence of singlet oxygen in biological systems involves the use of the following techniques: photon emission, emission spectra, product distributuion, D20 effect, DABCO effect, quencher effect and steady state techniques. Our experiments lead to the conclusion that singlet oxygen is present
Publicado em: 1981
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12. Prophage Induction in Escherichia coli (Lambda) by N-Nitrosamines
Carcinogenic N-nitrosamines were tested for their ability to induce λ in a lysogenic strain of Escherichia coli K-12 (58-161 F+). Dimethylnitrosamine, di-n-propylnitrosamine, methyl-n-propylnitrosamine, and N-nitrosopiperidine were shown to be inducers of prophage.