[Methods]A single oral 400 mg dose of racecadotril was given to 24 healthy male volunteers according to a randomized cross-over design. The Thiophine,a active metabolity of racecadotril,concentration in plasma was determined by HPLC-MS/MS method.
METHODS: The study was conducted as a 3- way crossover design in 18 healthy volunteers whose plasma concentrations of cefixime were determined by HPLC after receiving a single oral dose of 200 mg trial preparations or reference preparation.
The limit of determination,based on a signal-to-noise ratio of 3∶1,was 250ng. The reveals linearity equation was in concentration range 0.4099～0.6149mg·ml-1,A=7351270.8C-4136.7,r=0.9990.The cefpiramide could be separated effectively from its degradation product with the method.
RESULTS Paroxetine presented a good linearity within the concentration range of 10-100 mg·L-1,meanwhile both the inter-day and intra-day precision was less than 2%,and the mean recovery was 100.15% with RSD of 0.77%.
Studies in rats revealed dose dependency/ non-linearity in arteether pharmacokinetics with in the dose levels used.
In this study, we find that prodigiosin could effectively inhibit the proliferation of human pancreatic cancer cells H8898 in a dose-and-time-dependent manner, with an IC50 of 75μmol according to the results of MTT and cell proliferation assays.
Prodigiosin may effectively enter cells and promote the level of intracellular reactive oxygen species (ROSin) in a dose-dependent manner.
Doses ranging from 12.5-50 μM provided a dose-dependent reduction in the number of viable cells when compared to controls.
At the 50 μM dose, the number of viable cells was reduced by 65% suggesting potential antineoplastic effects of 9-O-methylfusarubin.
Results showed that over the concentration range of 6-16 mM, Me2SnCl2 is a chemical denaturant and denatures the double-strand DNA in a three-state manner.
Oxygen uptake by photobacteria was shown to be insensitive to chlorophenols, at least within the concentration range that was effective in bioluminescence inhibition.
The dependence of cell respiratory activity on the amount ofn-hexadecane within the concentration range of 0.03-0.66% was determined.
The microbial 1,3-β-1,6-β-glucan suppressed the defense response over a narrow concentration range (10-2M), whereas the plant pentasaccharide had a broad range of effective concentrations (10-12to 10-6M).
The method allows the determination of tungsten in protein samples in the concentration range of 0.05 to 0.4 μg/ml.