Sensitive determination of a pharmaceutical compound and its metabolites in human plasma by ultra-high performance liquid chromatography-tandem mass spectrometry with on-line solid-phase extraction.

This paper describes the determination of a drug candidate and two metabolites in human plasma by column-switching LC-MS/MS after protein precipitation. Starting from a standard method with a quantitation limit of 0.5 ng/mL, a highly sensitive assay was developed, employing UHPLC separation and detection on an API 5000 mass spectrometer.

[The adaptation of the microcirculatory bed of the major veins to the intermittent action of high-altitude hypoxia].

The present research was aimed at studying the structural trace of the adaptation of the large venous vessels microcirculatory bed to the interrupted action of high hypoxia. To obtain the adaptation 94 Wistar line rats were kept every day for 6 hours in the altitude chamber on the modelled height of 5000 meters for 45 days (control group made 20 animals). Intramural vascular bed was revealed by non-injective methods.