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3.
Food Addit Contam ; 22(7): 607-15, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16019836

RESUMO

A screening method for the detection of artificial colours (naphthol yellow, tartrazine, quinoline yellow, Sunset yellow, Allura red, amaranth, azorubine, Ponceau 4R and Red 2G) in saffron is described. The method involves removal of crocins by precipitation of crocetin (pH 0.1, 90 degrees C) before adsorption of the artificial colours on polyamide SPE cartridges (pH 2). After washing with methanol, acetone and methanol, elution was done with a methanol:ammonia solution (95:5 v/v), and detection was performed by derivative spectrometry. Sample pretreatment changes the UV-Vis saffron extract profile in such a way that second derivative spectra can be used to identify the presence of added colours. Erythrosine, which was found to be pH dependent, could not be detected under the above conditions. The lowest detectable amount for each colour was strongly dependent on chemical structure. The recovery of carminic acid was very low possibly due to irreversible retention on the polyamide. This procedure can replace the current ISO TLC method (2003) and be used alternatively or in combination with HPLC procedures adopted in the same standard.


Assuntos
Crocus/química , Corantes de Alimentos/análise , Contaminação de Alimentos , Especiarias , Antioxidantes/química , Carotenoides/química , Precipitação Química , Condimentos , Corantes de Alimentos/química , Concentração de Íons de Hidrogênio , Hidrólise , Análise Espectral/métodos , Raios Ultravioleta , Vitamina A/análogos & derivados
4.
Rev Esp Enferm Dig ; 93(7): 445-58, 2001 Jul.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-11685941

RESUMO

OBJECTIVE: To obtain data on research in laparoscopic digestive surgery over the period of 1991 to 1996. MATERIAL AND METHODS: We used Medline and the Science Citation Index to obtain general data on production. For more specific data (contents, etc.) we used random samples with a confidence level of 99%. RESULTS: There were 4825 publications on laparoscopic digestive surgery and 4.085 on other specialties; of these, articles represented 85% and editorials and letters 15%. University hospitals published 40% of this production. The producing countries were USA (45%), France (8.2%), United Kingdom (7.9%) and Germany (7.5%). The publishing countries were USA (41%), Germany (15.3%), United Kingdom (9.7%) and France (6.7%). The publication with the largest influence was the New England Journal of Medicine with a total Impact Factor of 589; the British Journal of Surgery with a factor of 436, Archives of Surgery with 343, American Journal of Surgery with 336 and Annals of Surgery with 302; the mean relative Impact Factor was 1.886. Method was involved in 756 retrospective studies, 275 prospective studies and 43 random clinical trials; the rest were not series. The majority of contents are on techniques and instruments, indications and general reflections. The most researched anatomical region was the gall bladder, followed by the bile ducts and the colon. The differences had a "z" > 1.645, that is to say, p < 0.05, and so considered statistically significant. CONCLUSIONS: The largest production and publication takes place in the USA and the journal with the greatest influence is the New England. Important studies on method are extremely scarce, random clinical trials representing only 1%.


Assuntos
Bibliometria , Endoscopia Gastrointestinal/estatística & dados numéricos , Humanos
5.
Rev. esp. enferm. dig ; 93(7): 445-451, jul. 2001.
Artigo em Es | IBECS | ID: ibc-10688

RESUMO

Objetivo: obtener datos sobre la investigación en cirugía digestiva laparoscópica, en los años 1991 a 1996.Material y métodos: usamos Medline y Science Citation Index para obtener los datos generales de producción; para los datos específicos (contenidos, etc.) utilizamos muestras aleatorias con nivel de confianza del 99 por ciento. Resultados: hay 4.825 publicaciones de cirugía digestiva laparoscópica y 4.085 de otras especialidades; son artículos el 85 por ciento, editoriales y cartas el 15 por ciento. Los hospitales universitarios publican un 40 por ciento. Los países productores son EE.UU. (45 por ciento), Francia (8,2 por ciento), Reino Unido (7,9 por ciento) y Alemania (7,5 por ciento). Los países editores son EE.UU. (41 por ciento), Alemania (15,3 por ciento), Reino Unido (9,7 por ciento) y Francia (6,7 por ciento). La mayor influencia la logra el N e w England Journal of Medicine, consiguiendo un factor de impacto total de 589; British Journal of Surgery 436, A r c h i v e s of Surgery 343, American Journal of Surgery 336 y A n n a l s of Surgery 302; el impacto medio relativo es de 1.886. Metodológicamente hay 756 estudios retrospectivos, 275 prospectivos y 43 ensayos clínicos aleatorizados; el resto no son series.Los contenidos mayoritarios son sobre técnicas e instrumental e indicaciones y reflexiones en general. La región anatómica más investigada es la vesícula biliar, seguida de las vías biliares y colon. Las diferencias tienen "z" > 1,645, es decir, p <0,05, por lo que son estadísticamente significativas. Conclusiones: la mayor producción y edición la realiza EE.UU. y la mayor influencia la consigue el New England. Son escasos los estudios metodológicamente importantes, siendo los ensayos clínicos aleatorizados sólo un 1 por ciento (AU)


Assuntos
Humanos , Bibliometria , Endoscopia Gastrointestinal
6.
Electrophoresis ; 22(8): 1479-83, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11386659

RESUMO

The available and total niacin evolution during maturation of yellow pea lupine (Lupinus luteus L., cv. Juno), pea (Pisum sativum L., cv. Ergo), faba bean (Vicia faba sp. minor Harz, cv. Tibo) and in germinated and high-pressure heated peas (Pisum sativum L., cv. Esla) have been determined by capillary electrophoresis (CE). The results have been compared with those obtained by high-performance liquid chromatography (HPLC). The values obtained by CE were similar to those obtained by HPLC. Maturation of seeds significantly reduced the available and total niacin content in legumes. The available/total niacin ratio during seed maturation depends on the type of legume. In faba beans and peas, a reduction was observed which was more pronounced in the case of peas. For lupine seeds, the ripening produced an increase (34%) in the available/total niacin ratio 50 days after flowering (DAF). Pea germination produced an overall increase in available and total niacin content although the available/total niacin ratio decreased. High pressure heating of pea yielded an increase in the available niacin content and available/total niacin ratio but the total niacin content did not change.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar/métodos , Fabaceae/química , Manipulação de Alimentos , Niacina/análise , Pisum sativum/química , Plantas Medicinais , Fabaceae/crescimento & desenvolvimento , Germinação , Pisum sativum/crescimento & desenvolvimento , Sementes/química , Sementes/crescimento & desenvolvimento
7.
J Agric Food Chem ; 49(4): 1854-60, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11308336

RESUMO

Lentil flours were extracted with 80% ethanol at 25 and 50 degrees C for 1, 2, or 3 h. The various nitrogen fractions, soluble carbohydrates, three amino acids (Lys, His, and Tyr), available lysine, protein digestibility, and vitamins B(1) and B(2) were analyzed to evaluate the effect of extraction. Extraction resulted in an increase in the total nitrogen content of the extracted flours, with extraction temperature affecting the nature of the nitrogen (protein or nonprotein) content. There was also a large reduction in the oligosaccharides of the raffinose family, although the effect of temperature was appreciable only in the case of stachyose. There was hardly any effect on the concentrations of the amino acids analyzed or on protein digestibility; however, a positive correlation between protein digestibility and the available lysine was recorded in the samples. The vitamin B(1) and B(2) contents underwent variable decreases depending on extraction temperature.


Assuntos
Fabaceae/química , Farinha/análise , Nitrogênio/análise , Proteínas de Plantas/análise , Plantas Medicinais , Aminoácidos/análise , Carboidratos/análise , Digestão , Etanol , Valor Nutritivo , Riboflavina/análise , Solventes , Temperatura , Tiamina/análise , Fatores de Tempo
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