Search results for "Photometry"
showing 10 items of 797 documents
Inhibition of antidepressant demethylation and hydroxylation by fluvoxamine in depressed patients.
1993
Bidirectional drug interactions between fluvoxamine and classical antidepressants were studied in depressed patients. A column switching technique combined with high performance liquid chromatography (HPLC) enabled automated analyses of plasma for simultaneous determination of fluvoxamine, tricyclic and tetracyclic antidepressants and demethylated and major hydroxylated metabolites in a single HPLC run. The measurements revealed that fluvoxamine inhibited N-demethylation of imipramine, clomipramine, amitriptyline and maprotiline whereas interferences with hydroxylation reactions were restricted to aromatic 8-hydroxylation of clomipramine. In patients under fluvoxamine monotherapy before com…
Healon5 versus Viscoat during cataract surgery: intraocular pressure, laser flare and corneal changes
2000
Background: The use of a viscoelastic substance facilitates cataract surgery. Healon 5 is a new viscoelastic product with special rheological properties. We evaluated the postoperative effect of Viscoat and Healon5 on intraocular pressure (IOP), central corneal thickness (CCT), endothelial cell counts and laser flare. Methods: Forty-eight eyes of 48 patients undergoing routine phacoemulsification followed by foldable IOL implantation were enrolled. Either Healon5 or Viscoat was used according to a block- randomization scheme. The aspiration technique was standardized. IOP, CCT, endothelial cell counts and laser flare were compared pre- and postoperatively. Statistical analysis was performed…
DNA image cytometry
1992
In 68 patients the DNA content of tumor cells was measured by image cytometry after resection of the rectum because of cancer. In the DNA histogram a differentiation between diploid (n = 19), polyploid (n = 24), hypotriploid (n = 17), and hypertriploid (n = 8) tumors was possible. The best relapse-free survival time was found in patients with diploid tumors. The prognosis worsened from polyploid to hypotriploid and was worse in hypertriploid tumors. Testing for a prognostic advantage of diploid over aneuploid tumors without adjustment for additional factors simply by means of the log-rank statistic gave a (one-sided) P of 0.1013. In a multivariate analysis the degree of differentiation turn…
IVIVC for fenofibrate immediate release tablets using solubility and permeability as in vitro predictors for pharmacokinetics.
2010
The goal of this study was to investigate the in vitro-in vivo correlation (IVIVC) for fenofibrate immediate release (IR) tablet formulations based on MeltDose-technique. The in vitro determined drug solubility and permeability data were related to the C(max) values observed from two in vivo human studies. Solubility and permeation studies of fenofibrate were conducted in medium simulating the fasted state conditions in the upper jejunum, containing the surfactant compositions of the six formulations at different concentrations. The behavior of all surfactant compositions was characterized by surface tension, dynamic light scattering, and cryo-TEM. The obtained solubility and permeation dat…
Intraoperative monitoring of cerebral microcirculation and oxygenation--a feasibility study using a novel photo-spectrometric laser-Doppler flowmetry.
2009
The present study assesses the utility of a novel invasive device (O2C-, oxygen-to-see-device) for intraoperative measurement of the cerebral microcirculation. CO2 vasoreactivity during 2 different propofol concentrations was used to investigate changes of capillary venous cerebral blood flow (rvCBF), oxygen saturation (srvO2), and hemoglobin concentration (rvHb) during craniotomy.Thirty-four patients were randomly assigned to a low propofol (4 mg/kg/h) versus a high propofol (6 mg/kg/h) group. A fiberoptic probe was applied on the cortex next to the surgical site. Measurements were performed during lower (35 mm Hg) and higher (45 mm Hg) levels of partial pressure of carbon dioxide (paCO2).…
Analysis of ecstasy in oral fluid by ion mobility spectrometry and infrared spectroscopy after liquid-liquid extraction.
2014
We developed and evaluated two different strategies for determining abuse drugs based on (i) the analysis of saliva by ion mobility spectrometry (IMS) after thermal desorption and (ii) the joint use of IMS and infrared (IR) spectroscopy after liquid-liquid microextraction (LLME) to enable the sensitivity-enhanced detection and double confirmation of ecstasy (MDMA) abuse. Both strategies proved effective for the intended purpose. Analysing saliva by IMS after thermal desorption, which provides a limit of detection (LOD) of 160μgL(-1), requires adding 0.2M acetic acid to the sample and using the truncated negative second derivative of the ion mobility spectrum. The joint use of IMS and IR spe…
Automated Determination of Ziprasidone by HPLC With Column Switching and Spectrophotometric Detection
2005
An isocratic high-performance liquid chromatography (HPLC) method with column switching and ultraviolet (UV) detection is described for quantitative analysis of the new antipsychotic drug ziprasidone. After centrifugation of serum or plasma samples and addition of fluperlapine as internal standard, the samples were injected into the HPLC system. On-line sample clean-up was conducted on a column (10 x 4.0 mm ID) filled with silica C8 material (20-microm particle size) using 8% (vol/vol) acetonitrile in deionized water as eluent. Ziprasidone was eluted and separated on ODS Hypersil C18 material (5 microm; column size 250 x 4.6 mm ID) using acetonitrile-water-tetramethylethylendiamine (50:49.6…
Endothelium-derived factors in microalbuminuric and nonmicroalbuminuric essential hypertensives
2000
Previous evidence has demonstrated a relationship between growth factors and cardiovascular diseases. This study was aimed at evaluating levels of some endothelium-derived growth factors, and their relationship with microalbuminuria (MAU), in essential hypertension. Ninety-nine mild-moderate essential hypertensives (EH) and 25 healthy controls were studied. All patients underwent 24-h blood pressure monitoring, serum endothelin-1 (ET-1), basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF), and 24-h MAU assays. Later, EH were divided into two subsets consisting of microalbuminurics (MAU >11 microg/min) and nonmicroalbuminurics (MAU <11 microg/min). In microalbumin…
Micro-lightguide spectrophotometry as an intraoral monitoring method in free vascular soft tissue flaps.
2003
Abstract Purpose: The aim of this prospective study was to measure the hemoglobin oxygen saturation (HbO2%) and relative Hb concentration of free vascular soft tissue flaps using micro-lightguide spectrophotometry. The objective was to measure the normal range and topographic differences in HbO2% and rel. Hb conc. in tissue transfers before establishing this as a clinical method for monitoring perfusion and vitality. Patients and Methods: In 39 patients who had received free vascular soft tissue flaps (34 radial forearm flaps; 8 latissimus flaps) to cover defects after tumor surgery, the capillary HbO2% in transferred tissue was measured spectrophotometrically preoperatively at the donor si…
Inflammation after sclerocorneal versus clear corneal tunnel phacoemulsification.
2000
Abstract Objective To compare the postoperative inflammation after phacoemulsification followed by intraocular lens (IOL) implantation by means of sclerocorneal versus clear corneal tunnel incision. Design Randomized controlled clinical trial. Participants One hundred eyes of 100 patients were examined at a German University eye hospital. Intervention One hundred eyes with cataract necessitating phacoemulsification with posterior chamber IOL implantation were randomly assigned to receive a temporal sclerocorneal or clear corneal tunnel incision by a single surgeon. Main outcome measures Preoperative and postoperative inflammation was evaluated by measurement of flare using laser flare photo…