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At least 127 records · Page 7Linked to original sources
PubMed1988

Sensitive quantification of pseudoephedrine in human plasma and urine by high-performance liquid chromatography.

An assay for the selective quantification of pseudoephedrine in human plasma and urine was developed using high-performance liquid chromatography with UV detection at 205 nm. Analyte and internal standard were extracted from alkaline plasma or urine into a mixture of n-hexane and diethyl ether, and the organic phase was back-extracted into dilute acid. The chromatographic system comprises microparticulate cyanopropyl-silica as stationary phase and a ternary solvent mixture with ion-pair reagents as mobile phase. Using 0.25 ml plasma, the lower limit of quantification was 25 ng/ml with excellent linearity up to 1000 ng/ml. In urine, the calibration ranged from 2.5 to 100 micrograms/ml. The selectivity of the method was demonstrated for several pharmaceuticals with similar structures. The validated method was applied to a pharmacokinetic study with a single oral dose of 100 mg of pseudoephedrine in two galenic formulations. Precision and accuracy data of the assay and calculated pharmacokinetic parameters are presented.

Adolescent↗
PubMed1982

Sequences of three molluscan 5 S ribosomal RNAs confirm the validity of a dynamic secondary structure model.

The collection of known 5 S rRNA primary structures is enriched with the sequences from three mollusca, the snails Helix pomatia and Arion rufus, and the mussel Mytilus edulis. The three sequences can be fitted in a five-helix secondary structure model previously shown (De Wachter et al. (1982) Biochimie 64, 311-329) to apply to all 5 S RNAs regardless of their origin. One of the helices in this model can undergo a bulge-internal loop transition. Within the metazoan kingdom, the dimensions of each helix and loop are rigidly conserved, except for one helix which can comprise either 6 or 7 base pairs.

Animals↗
PubMed1982

The rapid disability rating scale-2.

A revised version of the Rapid Disability Rating Scale (RDRS-2) is presented. Item definitions have been sharpened and directions expanded to indicate that ratings are based upon the patient's performance in regard to behavior, and that prosthesis normally used by the patient should be included in the assessment. Three items have been added to increase the breadth of the scale. Response items have been changed from three-point to four-point ratings in order to increase group discrimination amd make the scale more sensitive to changes in treatment. The new appraisals of reliability, factor structure, and validity are reported, along with the potential uses of the scale.

Activities of Daily Living↗
PubMed1991

Assessment and diagnosis of borderline personality disorder.

Borderline personality disorder is common in treatment settings and may be so in the general population. In this guide to assessment strategies for diagnosing borderline personality disorder, the authors discuss the reliability and validity of structured interviews and self-report instruments and suggest the use of a self-report questionnaire as a cost-effective screening test. Assessment problems, such as the need for longitudinal observation, are reviewed. Essential features of the recommended diagnostic approach include clarity about the diagnostic concept, consideration of the full range of diagnostic criteria, incorporation of recently developed diagnostic methodologies, care in distinguishing personality disorders from comorbid axis I syndromes, and complete assessment of the full range of axis II disorders.

Borderline Personality Disorder↗
PubMed1987

Analysis of individual, intraspecific and interspecific variability in quantitative parameters of caprine tooth enamel structure.

Qualitative and quantitative features of mammalian tooth enamel structure are increasingly being used in taxonomic and phylogenetic analyses, although the variability shown by these traits has not received adequate consideration. This study evaluates the variability displayed by nine quantitative parameters in deep, intermediate, and superficial molar enamel in the closely related bovids Ovis aries and Capra hircus. These parameters are assessed in terms of the absolute and/or relative variability evinced at a given depth within a single individual, among conspecific individuals, and between species samples. The degrees of relative variability expressed at a given depth are comparable among conspecific individuals and between taxonomic samples. Nevertheless, in many instances, there are significant differences in absolute variability amongst individuals. Also, in four parameters for which individual specimen averages could be calculated, the equality of these means among conspecifics can be rejected. Variability is not equivalent at different enamel depths. The null hypothesis of equality of individual, conspecific variances can be rejected most commonly for parameters measured in deep and superficial enamel, and coefficients of variation also tend to be higher for deep and superficial enamel than for enamel of intermediate depth. The greater variability displayed by deep and especially superficial enamel may be related to the initial onset and the terminal phase of ameloblastic secretory activity. Taxonomic and phylogenetic analyses that utilize quantitative data on enamel structure are valid only if comparisons have been made at equivalent enamel depths.

Ameloblasts↗
PubMed1985

[Criterion-oriented measurement in clinical psychology: development of a test on stress management].

Criterion-oriented tests evaluate the performance of the individual in relation to a given criterion which describes abilities and skills (intended competencies). The measuring process decides statistically if the person is "mastering" the criterion or not. The intended competencies should be represented by test items of high content-validity. The structure and application of this method especially to diagnostical issues of clinical psychology and therapeutic control are discussed. Steps are described construing a criterion-oriented test of stress and coping processes related to depressive and fearful behavior. The test is based on a situation-action-model in the theoretical framework of "stress and coping", "self-efficacy", "control" and "learned helplessness". Method and construction of items are shown in order to find some dimensions of coping-behavior-in-situations (appraisals, person-directed and environment-directed actions) and its sequential organisation in stressful episodes.

Adaptation, Psychological↗
PubMed1984

Estimation of individually adapted control parameters for an artificial beta cell.

For optimum long-term glycemic regulation using a miniaturized artificial beta cell it is indispensible to estimate control parameters suited to the individual requirements of each diabetic patient. To solve this problem, a strategy has been developed which is based on engineering optimum-control theory with a model involving glucose and insulin interactions. The model considers physiologically relevant unit processes like endogenous glucose production, insulin-independent glucose uptake from its apparent distribution space, insulin-dependent glucose utilization, glucose-dependent insulin supply, and insulin catabolism. The assumed model structure is validated by results obtained in experimentally diabetic dogs using partition analysis. The individual parameter values of the model are obtained by a digital computer procedure based on a simple test which involves a bolus injection of glucose + insulin when a constant basal insulin dose is being administered in the diabetic in whom normoglycemia was re-established before the test. The method presented is recommended for future use in all cases where an optimized insulin regimen is to be worked out.

Animals↗
PubMed1984

[Noninvasive monitoring with echocardiography. I. Ventricular function following thiopental and positive pressure breathing].

Using continuous M-mode echocardiography for measuring diameters of the left ventricle and calculating variables of left ventricular contractility during induction of anaesthesia the hemodynamic effects of thiopentone and of positive end-expiratory pressure breathing (PEEP) have been noninvasively assessed in 22 patients undergoing minor surgery (series A, n = 4 + 6, thiopentone) or cholecystectomy (series B, n = 12, PEEP). 4 mg X kg-1 i.v. (group I, n = 4) and 2 X 4 mg X kg-1, the second dose injected i.v. 5 min later (group II, n = 6), led in group I to a short lasting and in group II to a prolonged (duration of each experiment 10 min) significant decrease of the ejection fraction (EF), the shortening fraction (FS) and the mean velocity of circumferential fiber shortening (VCF mean). Thus the well known negative inotropic effect of thiopentone has been proven once more this time by noninvasive echocardiography. The influence of PEEP 5 and 10 cm H2O was evaluated in two ways: 1) by finding the incidence and extent of diminishing the "echocardiographic window" due to overexpansion of the lung during PEEP, rendering the sonographic visualization of the cardiac structures less valid, and 2) by assessing potential haemodynamic effects of PEEP. The curves of 3 in 12 cases (25%) have not been able to be evaluated properly because of "window closing"; in the residual 9 patients during PEEP 10 a significant decrease of the above mentioned parameters of contractility in comparison to PEEP 0 has been observed. IPPB without PEEP apparently does not disturb echocardiographic visualization.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1986

Simultaneous-successive factor structure of the WISC-R: a validation study.

It has been suggested that the Wechsler Intelligence Scale for Children--Revised (WISC--R) may usefully be interpreted in terms of a Simultaneous-Successive factor structure. A previous attempt to validate this hypothesis via factor analysis of 8 of the 12 WISC--R subtests was later shown to be an unreliable test of this model. The present study, performed upon 36 children, aged 6 1/2 to 12 1/2 yr., 45% female, 83% black, tested the validity of the two-factor model vis-á-vis the Kaufman Assessment Battery for Children (K-ABC), which is reported to have an unambiguous Simultaneous-Sequential (Successive) factor structure. Present results do not support a salient Simultaneous-Successive structure for the WISC--R, and clinicians should be wary of using the proposed two-factor model of the WISC--R for diagnostic or remedial purposes.

Child↗
PubMed1989

The Psychosomatic Symptom Checklist revisited: reliability and validity in a chronic pain population.

A psychometric evaluation of the SUNYA Revision of the Psychosomatic Symptom Checklist (PSC) was conducted with 405 chronic pain patients who completed the PSC as part of a diagnostic battery. Several properties of the measure were examined, including its reliability, internal consistency, discriminant validity, and factor structure. Contrary to a previous study, the measure demonstrated a modest reliability, a poor discriminant validity, and a multifactor structure that accounted for only a small proportion of the variance in the measure. Thus, the PSC did not appear to be an adequate measure of general psychosomatic distress when used with chronic pain patients. For these patients, the PSC may measure symptom clusters rather than general psychosomatic symptomatology. Since the PSC is used in various clinical populations, the results underscore the importance of investigating the properties of the measure in these populations.

Adult↗
PubMed1980

Mental retardation as a Facade Self phenomenon: construct validation.

Predictions from Wagner's Structural Analysis theory were tested to validate a theoretical explanation of the personality of mentally retarded adults. The Rorschach and Hand Test were administered to 44 medical students and 60 institutionalized mentally retarded adults. Results coincided with predictions based on Structural Analysis. Implications of these results for the diagnosis of mental retardation were discussed. The potential of a special Rorschach Facade Self Index for differential diagnosis of other forms of psychopathology was noted.

Adult↗
PubMed1992

Validity of exposure data derived from a structured questionnaire.

It is often convenient to obtain occupational exposure information directly from employees. However, there is little published evidence on the validity of such data. Information from a short, pre-coded, structured questionnaire, administered by non-expert interviewers, was compared with information derived from management in five factories in the printing and plastics industries in England in 1986. Values of sensitivity ranged from 24% to 85% for eight different exposures, and specificity was at least 67% for seven of the eight agents. Those exposures which were described in chemically specific terms tended to have relatively higher specificities but lower sensitivities. Male workers' reports tended to have higher sensitivity but lower specificity compared with those of female workers. Workers who had been employed in the company for more than 10 years were no more accurate than their colleagues. Subjects who reported a phase of subfertility or at least one miscarriage did not have a higher proportion of false positives than the population as a whole, indicating an absence of reporting bias. Major improvements are highly desirable, especially to reduce underreporting of exposures. The use of workers' own names for agents may improve reporting.

Age Factors↗
PubMed1987

Utility of fear survey schedule with Australian samples of anxiety disorder patients.

The Fear Survey Schedule (FSS) has been widely used in clinical settings for the assessment of anxiety disorders yet its reliability and validity is still in doubt. This paper reports the factor structure and the validity of the FSS using 130 agoraphobics with panic attacks, 98 phobics and 108 non-patient controls. The results show that a clear 6-factor solution can be derived from the FSS and this accounts for 46% of the variance. The 6 factors are (1) agoraphobia, (2) fear of small animals, (3) social anxiety, (4) negative social evaluation fears, (5) fear of bodily harm and (6) injury and fear of social interaction. The results of discriminate analysis show the following factors, that agoraphobics differ from phobics on agoraphobia, negative evaluations, fear of bodily harm and injury and social interaction fears. Compared with the non-patient group, agoraphobics differ in all factors except the small animal fear. The findings suggest that the FSS is a very robust and valid instrument for measuring fear in anxiety disorder patients.

Adolescent↗
PubMed1988

Evaluation of functional capacity after stroke with special emphasis on motor function and activities of daily living.

In a multidisciplinary study comprising 280 patients with acute cerebrovascular disease (median age 76, range 30-96 years), instruments for functional assessment in stroke care were developed. The improvements of motor function and activities of daily living were investigated during a period of up to one year after a stroke. A new chart for motor capacity assessment, which includes both the paretic and the non-paretic side, modified after that of Fugl-Meyer et al, was tested for its reliability and validity. At the same time the Activity Index of Hamrin & Wohlin was further tested. The internal consistency reliability measured with the standardized item alpha method confirmed that the two instruments have high homogeneity. Construct validity was investigated by factor analysis and showed a logical structure. The predictive validity of the scores on admission was significant and the two tools had a satisfactory predictive capacity for survival and later functional outcome. The improvements in different motor functions were followed up for up to one year after the stroke among the 183 one-year survivors. In patients with minor impairment, the improvement occurred mostly during the first week. Patients with moderate or moderately severe impairment improved more continuously for up to three months, while the few surviving patients with very severe impairment continued to recover to some extent even after three months. Older patients with severe functional loss seemed to improve more slowly and not as well as younger patients with equivalent impairment. The patterns of instrumental activities of daily living (I-ADL), such as household work, locomotion, psychosocial functions and intellectual activities, were investigated in the 207 three-month survivors and the 183 one-year survivors. At both the three-month and the one-year follow-ups the scores had decreased considerably, compared with before the stroke, for all activities except locomotion, and many patients were dependent on somebody else for help. The same group of patients was also examined by a Standardized Practical Equipment (SPE) test constructed by Tömquist three months and one year after the stroke. The construct validity of the SPE test was estimated through factor analysis. Three factors emerged, one concerning mainly cognitive factors and co-ordination, one concerning hand function and one concerning mainly mobility and balance. The instruments developed in the course of this study have proved to be reliable and valid, and useful in assessing functional losses and following progress. The tools are well suited for any clinical settings and for home care examinations as well as research.

Activities of Daily Living↗
PubMed2026

Genomic and Molecular Interaction Analysis of NodD1 in a Novel Bradyrhizobium yuanmingense sp. B64 Isolate for Nodulation and Symbiosis of Legume Plants.

Rhizobial bacteria are known for their ability to fix nitrogen for leguminous plants and their essential function for sustainable agriculture. This study characterizes the taxonomic status and functional potential of the Bradyrhizobium B64 isolate using integrated genomic and molecular approaches. The whole genome of the B64 isolate was sequenced via Illumina paired-end technology. Species delimitation was performed using average nucleotide identity (ANI) and digital DNA-DNA Hybridization (dDDH). The NodD1 protein structure was modeled using AlphaFold3 and validated by Ramachandran plot analysis. Molecular docking was then conducted to evaluate interactions between NodD1 and four signaling flavonoids: Apigenin, Daidzein, Genistein, and Naringenin. Genomic analysis revealed a maximum ANI of 94.4% and dDDH values between 51.4 and 62.4%. Since these values fall below the standard prokaryotic thresholds (ANI&#x2009;<&#x2009;95%; dDDH&#x2009;<&#x2009;70%), the B64 isolate is identified as a novel species. Physiological assays confirmed nitrogen fixation (1.97 ppm), IAA production (3.67 ppm), and phosphate solubilization (26.10 ppm). Structural validation showed 100% of NodD1 residues in allowed regions, ensuring high model reliability. Docking simulations demonstrated strong binding affinities across all flavonoids, with binding free energies ranging from -&#x2009;8.8 to -&#x2009;9.0&#xa0;kcal/mol. Daidzein exhibited the highest thermodynamic stability (-&#x2009;9.0&#xa0;kcal/mol), whereas apigenin showed the most extensive residue interaction network. The B64 isolate is a novel Bradyrhizobium species with a high symbiotic capacity. The stable NodD1-flavonoid interactions provide a molecular basis for efficient nodulation, positioning B64 as a promising candidate for developing lipo-chitooligosaccharide (LCO)-based biofertilizers.

Bradyrhizobium↗
PubMed1989

A factorial, reliability, and validity study of the Devereux Elementary School Behavior Rating Scale.

This investigation explored the factor structure, reliability, and validity of the Devereux Elementary School Behavior Rating Scale, employing a large (n = 648) sample of children. Factor analysis suggested that the Devereux scale can be described by four factors, which were named Disruptive-Oppositional, Poor Comprehension-Disattention, Cooperative-Initiating, and Performance Anxiety. All four factors showed high internal consistency, and three of the four were stable over a 17-mo. period. Correlations of the four factors with academic achievement, IQ, socioeconomic status, and peer ratings of social competence are presented. All four factors showed significant relations with these variables, with Poor Comprehension-Disattention the strongest of all. Multiple regression analysis indicated that the Poor Comprehension-Disattention factor accounted for significant variance in academic achievement even after IQ was taken into account. Large differences between classroom means on the factor scores suggested that Devereux ratings for individual students may need to be interpreted cautiously.

Achievement↗