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A factorial experiment was performed in the fodder broad bean to analyse effects of soil drought on the development and yield components of two varieties of different morphotype: 'Nadwislanski' (traditional) and 'Tim' (determinate growth habit). Plants were grown in Mitscherlich's pots under three different soil moistures: 70%, 50% and 30% of field water capacity. The soil water shortage contributed to a considerable depression in the developmental characteristics and yield traits of both varieties. Under all conditions, the variety 'Nadwislanski yielded more seeds than did 'Tim'. The traditional variety was more resistant to drought than the new 'Tim'.

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The delivery and pharmacokinetics of cyclosporine A (CyA) given locally to the airways or iv was evaluated in young and adult rats. After intratracheal (i.t.) instillation of saline suspended CyA to adult rats, the CyA plasma levels peaked at 30 min with a bioavailability of 78.1 +/- 6.9%. After the i.t. instillation of CyA with micelles forming surfactant, Cremophor EL, in adult and young rats, the plasma levels peaked at 5 min with a bioavailability of 77.5 +/- 7.2% and 66.3 +/- 4.5%, respectively. The bioavailability of aerosolized CyA was 80.1 +/- 4.1% in adults. Thus, CyA is absorbed by the lungs into the systemic circulation of the rat in high amounts, independent of age and type of delivery system. Long-term treatment with i.t. instillations did not affect body weight gain in young and adult rats, and no histopathological changes were found in the lungs. It is important to emphasize that CyA plasma clearance in young rats was lower and elimination half-life longer than in adults. The slow elimination of CyA in young rats indicated profound pharmacokinetic age differences for this species.

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We studied the surfaces of six precision-ground optical glass samples of fused silica, BK-7, BaCD16, LaC14, NbF1, and LHG8 glass, using a mechanical profiler, a photon tunneling microscope, and a scanning force microscope. The measured roughnesses of the scanning force microscope varied from 3.5 A rms for BK-7 glass to 30 A rms for LHG8 laser glass. Good agreement was obtained among the roughness values measured with all three instruments.

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Digoxin in salvia and blood serum of 24 patients obtained Bemecor was determined by the method of FPIA (IMx-ABBOT). Mixed saliva was collected by three different types of Salivette (Sarstedt) given in order: normal Salivette with cotton wool swab, Slivette with polyester wool and Salivette with citric acid as a stimulator. It was found, that the correletio between the digoxin concentrations in saliva and serum and saliva/serum rations depended on the type of Salivette. The highest correlation was obtained with the Salivette with polyester wool (r = 0.892), but low concentrations of this drug in serum were good reflected in all samples of saliva, independent on kind of Salivette.

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The roughnesses of five supersmooth dielectric films of Si(3)N(4), TiO(2), HfO(2), Ta(2)O(5), and Al(2)O(3) prepared by an ion-beam-sputtering technique were measured with a commercial Talystep mechanical profiler and a sensitive Leica WYKO SPM30 scanning force microscope (SFM) to determine how much roughness the films added to the ∼1-Å-rms roughness fused-silica substrates on which they were deposited. In all cases the increase in roughness for the three-quarter-wave optical thickness films was a small fraction of an angstrom. SFM measurements showed that the topography of the Ta(2)O(5) and Al(2)O(3) films was less random than that of the other film materials and the substrates.

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The scanning force microscope (SFM) is used to study the characteristics of optical surfaces, such as polished and precision-machined surfaces and thin-film structures. Previously unreported images of raised surface scratches and clumpiness on the surface of extremely smooth dielectric films are presented. The characteristics of SFM's that are important in studying optical surfaces are discussed. They include the effects of tip geometry, surface charging, particulate contamination, scanner artifacts, and instrument calibration.

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A HPLC method for the determination of mexiletine in human plasma and serum is described. Serum or plasma after addition of mexiletine and internal standard was extracted with diisopropyl ether. The extract was then evaporated and dissolved in the mobile phase. An aliquot of the solution was chromatographed on a reversed-phase C8 column. The peaks were detected by UV (214 nm) at room temperature. The limit of detection of mexiletine was approximately 0.02 mg/l of plasma or serum. The validity of the method is discussed and compared with other methods.

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A liquid chromatographic method for the assay of antiarrhythmic drug amiodarone and its metabolite desethylamiodarone in human plasma or serum has been developed. The method is simple and sufficiently sensitive for pharmacokinetic studies. Amiodarone, desethylamiodarone and added internal standard L 8040 were twice extracted at various pH from serum or plasma. The extract after evaporation was reconstituted in the mobile phase and chromatographed on reversed phase Hibar LiChrosorb RP-8 column with UV detection, at 254 nm. The method is specific and can detect approximately 30 ng of amiodarone and desethylamiodarone in 1 ml of plasma or serum.

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A method for simultaneous determination of clobazam (CBZ) and its active metabolite N-desmethylclobazam (DCBZ) in various biological samples by RP-HPLC with UV detection is described. The determination of both CBZ and DCBZ is performed without derivatization. The internal standard is diazepam. The method is rapid and simple with sensitivity limits of 10 ng/mL for both CBZ and DCBZ and is suitable for routine analysis as well as for animal studies.

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Relative bioavailability of amiodarone was studied in 10 healthy volunteers after its 600 mg single dose administration. Mean values of individual maximal concentrations and time for reaching them did not significantly differ and were respectively 0.828 +/- 0.401 microgram/ml and 4.4 +/- 1.5 h for Amiodarone preparation Polfa and 0.541 +/- 0.207 microgram/ml and 5.2 +/- 1.6 h for Cordarone preparation. Bioavailability extent (EBA) of examined preparation was 120 per cent in comparison with the standard one. Amiodarone absorption from both preparations was slow and individually diversified. Absorption rate constant Ka did not statistically significant differ and was respectively 0.35 +/- 0.10 1/h and 0.49 +/- 0.35 1/h. Obtained data indicated that both preparations were biologically equivalent.

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The usefulness of determination of salivary concentrations of theophylline for estimation of the serum concentration of the drug was tested in asthmatic children receiving daily 15-20 mg/kg of aminophylline. Theophylline was measured in saliva samples obtained after stimulation with citric acid and bromhexine, and in the blood serum, and the ratio of saliva: serum theophylline concentrations was calculated. The correlation between saliva and serum theophylline concentration was better for saliva samples obtained after bromhexine stimulation (r = 0.9496) than after citric acid stimulation (r = 0.8506). Using the mean value of the saliva: tissue theophylline concentration ratio of 0.6795, the serum theophylline concentration may be satisfactorily predicted (r = 0.9810). The stimulation of salivation with bromhexine is more suitable for the Abbott TDX Drug Monitoring System than the stimulation with citric acid, and the method is suitable for a routine monitoring of theophylline concentrations in the course of theophylline therapy.

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Differences in late event-related potentials (ERPs) during active respond-withhold tasks were tested with 16 young, 16 middle-aged, and 16 elderly subjects (mean ages were 30, 50 and 69 years, respectively). All subjects were selected for good health. While monopolar electroencephalograms were recorded from FZ, CZ, and PZ, subjects performed a signaled respond-withhold task to allow measurement of sustained potentials (SPs) and a non-signaled respond-withhold task for measurement of P3 responses and late activity (LA) which follows the P3. Respond and withhold trials were presented randomly with a probability of 0.5 in both tasks. Compared with younger subjects, the elderly group produced significantly larger negative mean SP amplitude during respond trials at CZ, significantly larger negative mean LA during respond trials at CZ, and significantly larger positive LA during withhold trials at all electrode locations. The elderly group also produced significantly larger P3 amplitude at FZ. The results are discussed in relation to the hypothesis that inhibition may be weaker in elderly subjects. Two further possible interpretations of the larger ERPs in elderly subjects are suggested: (1) the elderly group may have been more challenged by the tasks and their larger ERPs may reflect greater neural effort; and/or (2) the health selection procedures may have produced a group of elderly 'survivors' whose large ERPs may be characteristic of robust individuals or may reflect adaptations to aging-related changes in neural function.

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In serum samples of 20 children the concentration of amikacin, gentamicin and tobramycin was determined paralelly by use of conventional microbiological method and fluoroimmunoassay technique. Peak concentration of tested aminoglycosides was observed 60 min after the first administration of the drug. The "trough level" of amikacin was lower than 10 micrograms/ml and that of gentamicin and tobramycin lower than 2 microgram/ml. Serum concentration of aminoglycosides in samples tested by microbiological assays and fluoroimmunoassay test was similar, correlation coefficient was 0.93.

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Relationships between physiological responses and slowed reaction time (RT) among elderly subjects were tested in 48 healthy young, middle-aged, and elderly men (mean ages 24, 45, and 71 years) using simple and choice RT tasks. There were age reductions in P3 amplitude and heart rate (HR) deceleration, but no effects of age on P3 latency. Sustained potential (SP or CNV) amplitude paradoxically increased with age, possibly indicating weaker inhibitory function. P3 amplitude, SP amplitude, and HR deceleration were most strongly correlated with RT among younger subjects, but SP amplitude was correlated with RT in the elderly group during the choice task. HR deceleration shared a small amount of variance with SP amplitude and RT in the young group. There was no HR-SP-RT relationship in the older groups. Choice-simple task differences in P3 amplitude and RT were correlated in the young and elderly groups. The results suggest that HR, SP, and P3 responses may reflect physiological processes related to the slower RTs of healthy elderly subjects.

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