Wyniki wyszukiwania - Biblioteka Nauki

1

An approximate cooperativity analysis of the phase transitions of DPPC-DOCna dispersions

100%

Hobai S. , Fazakas Z.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr 2

2

The role of reduced glutathione in bile formation in sheep

75%

Bobowiec R. , Kosior-Korzecka U. , Martelli F. , Sighieri C.

Polish Journal of Veterinary Sciences

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1999

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tom 02

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nr 1

EN

The present study reports the investigation on the influence of reduced glutathione (GSH) on bile secretion in 4 canulated sheep during constant intraduodenal infusion of bile alone, bile with sodium taurocholate (TCHNa) or bile with sodium deoxycholate (DCHNa). Infusions of bile alone and bile with TCHNa or DCHNa brought about an increase in the bile salts secretion from 0.05 ± 0.01 (μM/min/kg to the value of 0.12 ± 0.03, 0.22 ± 0.07 and 0.32 ± 0.08 μM/min/kg, respectively. It was shown that the administration of GSH during the infusion of both bile alone and bile+bile salts slightly but significantly (p < 0.05) lowered bile salts secretion. At the same time both bile with glutathione and bile+bile salts+glutathione increased the bile flow significantly (p < 0.05) as compared to that found after infusions without glutathione. After the i.v. administration of GSH, the volume of the bile increased to a lesser extent than it did with bile+TCHNa or, especially, with bi- le+DCHNa infusions. The concentration of glutathione in the bile was the highest during the infusion of bile+DCHNa (671.18 ng/ml), lower during the infusion of bile+TCHNa (471.40 ng/ml) and the lowest during the infusion of bile alone. Although the bile salts secretion decreased during the simultaneous infusion of the bile with bile salts and glutathione, there was an increase in the bile flow. Therefore, we concluded that some bile acid independent fraction was secreted into the bile and that the fraction was dependent on GSH secretion at the level of canaliculi.

3

Factors influencing the restitution of the duodenal and colonic mucosa after damage

63%

Riegler M. , Feil W. , Wenzl E. , Schiessel R.

Journal of Physiology and Pharmacology

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1991

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tom 42

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nr 1

EN

Rapid epithelial restitution is an important protective mechanism which enables the gastrointestinal mucosa to reestablish epithelial integrity following superficial injury within hours. In this study we examined the influence of an acidic luminal pH, removal of the necrotic layer, nutrient bicarbonate, calcium and sodium desoxycholate (Na-DOC) on restitution in the rabbit duodenum in vitro and the role of Na-DOC and calcium for rapid restitution of the human colon in vitro. Transmucosal potential difference (PD), short-circuit current (lsc) were measured and resistance against passive ion flux (R) was calculated. Electrophysiological changes paralleled morphological injury but did not necessarily reflect restitution in all experiments. The extent of mucosal injury was assessed by computerized real-time morphometry. 5 hrs after luminal exposure to 10 mH HCl for 10 min residual damage (RD) was 14% in the duodenum. Luminal pH of 3.0 (RD of 30%), removal of necrotic layer at acidic luminal pH (RD of 66%), absence of bicarbonate from the serosal solution (RD of 35 % at neutral luminal pH; RD of 96% at acidic luminal pH) and removal of calcium from the serosal solution (RD of 58 %) impaired restitution in the duodenum. Continuous postinjury luminal Na-DOC exposure did not influence restitution in the duodenum (RD of 19%). 5 hrs after luminal exposure to 0.5 mM Na-DOC for 10 min RD was 26% in the human colon. Continuous postinjury luminal Na-DOC exposure (RD of 51 %) and removal of calcium from the nutrient solution (RD of 65 %) impaired restitution in the human colon. Thus we conclude that restitution of the rabbit duodenum in vitro requires a necrotic layer and bicarbonate flux to withstand acidic luminal pH, while restitution is not Effected by Na-DOC. In the human colon Na-DOC inhibits restitution. Both the duodenum and colon require calcium for rapid restitution.

4

Sole sodowe kwasów cholowych jako chiralne modyfikatory fazy ruchomej w układzie wysokosprawnej chromatografii cieczowej

51%

Kowalczyk M. , Asztemborska M.

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2011

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tom Vol. 3, No. 1

161--184

PL

W pracy opisano zastosowanie cholanu sodu i deoksycholanu sodu, jako modyfikatorów fazy ruchomej w wysokosprawnej chromatografii cieczowej. Własności enancjoseparacyjne micelarnych faz chiralnych dla optycznie czynnych pochodnych binaftyli: fosforanu- 1,1’- -binaftylo-2,2’-diylu oraz 1,1’-binaftylo-2,2’-diolu. Zbadano proces adsorpcji cholanu i deoksycholanu sodu na fazie C18. Zbadano wpływ stężenia i typu surfaktantu, jak również rodzaj i stężenie dodatku organicznego (n-alkohol) na proces rozpoznania chiralnego przez badane układy micelarne.

EN

In the paper the application of sodium cholate and sodium deoxycholate as modifiers of mobile phase in high performance liquid chromatography was described. Enantioseparation properties of micellar chiral phases were studied for optically active derivatives of binaphthyls: 1,1'-binaphthyl-2,2'-diyl hydrogenphosphate and 1,1'-binaphthalene-2,2'-diol. The process of adsorption of sodium cholate and sodium deoxycholate on C18 phase was studied. The influence of type and concentration of surfactant as well as type and concentration of organic additive (n-alcohol) on process of chiral recognition was investigated. It has been found that enantiorecognition of bile salts micelle increase with the increase of the chain length of n-alcohol.