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At least 19 recordsLinked to original sources
PubMed1976

[Investigations on the Variability of the phasic pupillary light reflex (author's transl)].

Infrared pupillography was used to determine physiological time parameters of the direct phasic light reflex in 101 normal subjects. These parameters include latency, contraction and redilatation times as well as total reaction time, measured in response to 4 different light stimulus intensities. A total of more than 4000 pupillary stimulations in these subjects was analyzed statistically. The study of these time parameters included determination of the mean, the standard deviation and three dimensional analysis of variance, with the following results: 1. The physiological time parameters are bilaterally symmetrical. 2. The most stable parameters with least variability in an individual subject were latency and contraction time. The redilatation time, however, showed marked intra-individual variability. 3. Variance analysis revealed a high degree of correlation among the different parameters to light stimuli of varying intensity. 4. There was a highly significant prolongation of latency and of contraction time with increasing age. 5. No sex dependent effect on physiological time parameters was found. In addition, no interaction among light stimulus intensity, age and sex could be detected. Possible applications of the method for clinical neurological examination are discussed.

Adolescent↗
PubMed1978

[The influence of disodium cromoglycate (DNCG) on the phagocytotic activity of neutrophile granulocytes (author's transl)].

Disodium cromoglycate (Intal) inhibits in vitro the phagocytotic activity of neutrophile granulocytes. In thirteen pairs of blinding analysed experiments it could be shown that the DNCG incubatet blood samples had a phagocytotic index below that of the control. The statistical significance of these findings was assessed by a variance analysis.

Analysis of Variance↗
PubMed1977

Applications of statistical equivalence to newborn EEG recordings.

Epochs were selected from sleep EEGs of newborns during both quiet and REM phases. A first order parameter analysis was done in order to test the homogeneity (run test and one way variance analysis) of the data within the epochs, follwed by a study of spectral equivalence between epochs. Comparisons were made between average spectra in the frequency range 0.5--4 c/sec; and between their band-by-band components, to test the feasibility of automatic classification of sleep stages by means of frequency analysis. On the basis of the statistical parameters we used, spectral analysis appears to be of limited value for the purpose of automatic classification of newborn EEG records; due to a lack of complete homogeneity of the spectra within each sleep state, it is not possible to identify a characteristic spectrum for active sleep and quiet sleep.

Electroencephalography↗
PubMed1976

Acebultolol: basis for the prediction of effect on exercise tolerance.

Twelve unselected males suffering from documented coronary insufficiency and moderately severe angina submitted to graded multistage treadmill exercise testing on 3 separate days, 3.5 hr after a single dose of 0,200, or 400 mg of acebulolol, a cardioselective beta blocker. Control measures included random allocation of 2 patients to each of 6 balanced sequences of administration, standardized double-blind conditions, and variance analysis for Latin-square design with repeated measures on each subject. Performance was evaluated by measuring time elapsed until anginal pain, peak heart rate, peak product of heart rate and blood pressure, and peak oxygen consumption. Mean values for all criteria were significantly atered by 400 mg of acebutolol. Seven out of twelve patients were classified as responders (i.e., exercise duration increased 100% or more). The response after acebutolol was correlated with the performance on placebo in the base of exercise duration, peak heart rate, and peak product of heart rate and blood pressure. It is concluded that: (1) performance criteria are useful predictors of response to beta blockade and (2) acebutolol is a potent antianginal agent when judged by an objective treadmill exercise test.

Acebutolol↗
PubMed1979

Influence of ciclazindol on monoamine uptake and CNS function in normal subjects.

The potential antidepressant drug ciclazindol inhibited dopamine uptake into human platelets without affecting 5-hydroxytryptamine uptake as compared with a control. It inhibited the tyramine pressor response less than desipramine after single 50-mg oral doses in 6 healthy volunteers under double-blind conditions. Compared with tandamine in a double-blind placebo-controlled study in nine healthy subjects, ciclazindol 50 mg orally caused no significant anticholinergic effects but reduced appetite according to an analysis of variance. Nonparametric analysis did not confirm the anorectic effect. Previous studies had shown that ciclazindol increased glucose uptake into isolated human skeletal muscle independently of insulin. Overall, ciclazindol resembles the antiobesity drug mazindol in molecular structure and pharmacological effects in man. Interactions with sympathomimetic amines and adrenergic neurone-blocking drugs cannot be excluded on the basis of these studies.

Adult↗
PubMed1976

Cigarette smoking in pregnancy: Associations with maternal weight gain and fetal growth.

1159 mother-infant "pairs" have been studied to examine the inter-relationship of cigarette smoking in the latter half of pregnancy, maternal weight gain, and fetal growth. Non-smokers gained significantly more weight than heavy smokers (greater than 15 cigarettes per day) while light-to-moderate smokers (1-14 cigarettes a day) were intermediate. Birth-weight, length, and head circumference of the infants showed a similar gradient with infants born to non-smokers being heavier, longer, and with larger head circumferences than those born to heavy smokers. Co-variance analysis showed that a large part of the effect of maternal smoking is mediated through maternal weight gain with only a very small additional direct effect on the fetus. This suggests that increasing weight gain in smoking mothers might prevent some of the harmful effects of smoking on fetal growth. A randomised controlled trial of diet supplementation of smoking mothers would seem justified.

Birth Weight↗
PubMed1979

Correlation between genetic regulation of antibody responsiveness and protective immunity induced by Plasmodium berghei vaccination.

High (H) and low (L) antibody responder lines of mice were produced by two independent bidirectional selective breedings for quantitative antibody responsiveness to heterologous erythrocytes (selection I and selection II). In both selections the antibody response to P. berghei antigens was 8- to 10-fold higher in H than in L lines. The character "high response" presents an incomplete dominance o- 18% in selection I and 67% in selection II. In selection II the variance analysis indicates that at least three independent loci intervene in the regulation of responsiveness to P. berghei antigens. The innate resistance and the protective efficacy of vaccination against P. berghei infection induced by parasitized erythrocytes was measured in H and L lines and in the interline hybrids F1, BcH, and BcL of selections I and II. No very significant difference was observed in the innate resistance to P. berghei infection between H and L mice of both selections. Vaccination induced a very efficient protection in the two H lines (94 and 95% survival), whereas only a weak protection was induced in the two L lines (16 and 31% survival); the degree of protection is intermediate in interline hybrids F1, BcH, and BcL. In both selections a good linear correlation was demonstrated between the level of vaccination-induced antibody and the degree of resistance measured as percentage of survival. The present results indicate that the vaccination-induced P. berghei immunity is essentially due to the antibody response, whereas the bactericidal activity of macrophages and the cell-mediated immunity do not play a determinant role.

Animals↗
PubMedDate not supplied

Physical fitness in different groups of industrial workers.

Maximum oxygen consumption was determined by the indirect method (with submaximal effort) in 155 forestry workers, 120 miners, 240 tool manufacturers (turners, planers etc.), 75 control-board operators. Differences were found according both to age and occupation. Variance analysis showed that age had a greater impact (F = 68) than occupation (F = 20). The highest values were recorded in foresters (57 -- 39 ml/kg/min depending on age). In miners the average values were 49 -- 35 ml/kg/min, while toolmakers and pannel operators showed maximum oxygen consumption of 45 -- 32 ml/kg/min, VO2 being nearly the same in both groups of occupation for the respective groups of age. Values of 50 ml/kg/min or above were found in 88% of 20 -- 29 year -old foresters and in 54% of the miners, while in toolmakers and in pannel operators such vales of VO2 were found only in 37% and 27% respectively, of the cases.

Adolescent↗
PubMed1979

Potency of PPD preparations derived from M. tuberculosis and M. bovis.

No significant difference was found between the biological activity of PPD-preparations derived from M. tuberculosis and M. bovis, although the latter was more potent. In potency tests performed in guinea-pigs, the use of difference mycobacteria as sensitizing agents had no influence on the result of the assay. We could not demonstrate a significantly greater potency of homologous versus heterologous PPD. Evaluation of the 95 p.c. fiducial limits established in the course of variance analysis suggested a greater reliability of reading at 48 than at 24 hrs after allergen application. It also seems possible that the results of the potency assays of PPDs derived from different mycobacterium strains are greatly influenced by the level of the working dilutions employed.

Animals↗
PubMed1976

Varicella-zoster antibodies in adult patient with haemoblastoses.

Indirect haemagglutination (IH) antibodies to varicella-zoster (VZ) virus were investigated, under the identical conditions of a single experiment, in a group of patients with haemoblastoses and 80 normal adults of equal age groups. Statistical significance of the differences in VZ antibody geometric mean titres between the individual haemoblastoses and normal controls was examined by means of variance analysis. A significantly raised mean titre was still found in the Hodgkin's disease group.

Adult↗
PubMedDate not supplied

Variations in the capacity of the steroid binding beta globulin (SBbetaG) in plasma from normal young twins.

The capacity of human plasma to bind specifically dihydrotestosterone (DHTBC) has been determined in normal monozygotic and dizygotic twins less than 20 years old. The total variation in DHTBC was analysed by stepwise multiple regression, combined with variance analysis, applied to the pair sums in DHTBC, body height and body weight, as well as to age. A significant part of the variation in DHTBC was explained. Due to the strong interwining between body weight, body height and age in growing children it was impossible to make out which one of the latter variable contributed most to the negative correlation which was observed. Previous studies in adults did, however, show that only body weight and not body height or age correlated negatively with DHTBC. By doing the same calculations for the within-pair differences in DHTBC, body height and body weight it was hoped to delineate the within-family part of the environmental variation in DHTBC. Body weight and body height did, however, not offer any significant explanation as to this part of the variation in DHTBC. The upper limit of heritability (h2) for DHTBC was estimated by comparing intraclass-correlation coefficients in monozygotic and dizygotic twins. According to the method used to calculate the latter intraclass-correlation coefficients h2 estimates for DHTBC of 0.774 and 0.960 were arrived at. However, due to the rather small number of dizygotic twins available the confidence limits of these estimates were rather large.

Adolescent↗
PubMed2026

Assessment of Genetic Diversity and Population Structure on Azadirachta indica A. Juss. in an Urban Metropolitan: Ahmedabad, India.

Azadirachta indica (A. indica) A. Juss., commonly known as Neem, is a valuable multipurpose tree with profound medicinal properties and socioeconomic importance, widely recognized since ancient Ayurvedic times. Despite its prominence, knowledge about its genetic diversity within the metropolitan area of Ahmedabad is limited. This study marks the first in-depth exploration of the genetic diversity and population structure of A. indica in Ahmedabad. The authenticity of the species was validated through DNA barcoding, and a Geographical Information System (GIS) was used to collect the samples. A total of 35 A. indica accessions were analyzed using five Inter Simple Sequence Repeat (ISSR) primers. Genetic diversity and population structure were evaluated using Inter Simple Sequence Repeat (ISSR) markers through polymorphism assessment, clustering, ordination, and Bayesian population structure analyses. ISSRs revealed a high level of polymorphism (75.66%), indicating substantial genetic variability among accessions. An analysis of genetic diversity indices revealed low to moderate diversity (Hs = 0.14, Ht = 0.217, I = 0.217). Analysis of Molecular Variance (AMOVA) analysis depicted 81% variation within the population and 19% among the population. Low to moderate genetic differentiation (Gst = 0.319) and moderate gene flow (Nm = 1.06) indicated that urban development has not hindered gene flow among populations. Mantel's test revealed a weak but significant correlation between genetic and geographic distances, suggesting limited isolation by distance. The estimated ΔK using STRUCTURE exhibited two subpopulations, representing two gene pools for A. indica accessions (K = 2). Collectively, these patterns indicate that urbanization has not severely disrupted genetic connectivity in A. indica, reflecting its resilience and adaptive potential in a metropolitan environment. These findings provide pivotal knowledge for further understanding the genetic diversity and population structure of A. indica in one of the fastest-growing cities in India, which can be utilized for new breeding programmes, sustainable development and future conservation strategies around the globe.

India↗
PubMed1979

[Combined effect of alkylating compounds on human chromosomes].

A combined effect of thiophosphamide and dipin on chromosomes of unstimulated human lymphocytes was studied in experiments carried out thrice according to the scheme of a complete two-factor experiment. The exposure to the mutagens lasted for an hour, the concentrations being from 3.17 to 22.19 . 10-5 M. After washing a fresh medium with PHA was added to lymphocytes and then they were cultivated during 60 hrs. Both at separate and combined action of tested chemicals the effect observed in all the cytogenetic tests was not subjected to a linear dependence on the concentration of mutagens. With the change in the proportion between thiophosphamide and dipin, given that the summed number of their molecules was constant, the cytogenetic effect was directly proportional to the part of each mutagen in a combined treatment. The analysis of variance and regression analysis of the results obtained as well as the analysis of types of appearing chromosome aberrations and the analysis of distribution of breaks in cells at the combined action showed that, taking into account that the concentration dependences were not linear. the combined effect of thiophosphamide and dipin was additive, without any interaction of individual effects.

Alkylating Agents↗
PubMed1979

The ultradian pulsatile release of gonadotropins in normal female subjects.

With an original statistical study which employes the analysis of variance and the harmonic analysis, the authors evaluated the levels of LH and FSH obtained from 5 female patients of the infertility clinic. These subjects, apparently free from endocrine disorders, underwent a 7-hour test consisting of samples obtained at 20 minute intervals. By a double-antibody RIA method, we assayed LH and FSH in quintuplicate or triplicate in each sample and counted the tubes twice consecutively. In all subjects for LH and in 3 subjects for FSH we detected a real ultradian pulsatile release of the hormone. Period and amplitude of the LH fluctuations vary according to the phase of the menstrual cycle (follicular phase: short period and low amplitude; luteal phase: long period and high amplitude). No change in amplitude was observed for FSH, while the period in two cases varied in accordance with LH. In two cases we found multiple periods in the fluctuations of one hormone during the same test.

Adult↗
PubMed2026

Lateral Femoral Condyle Angle Is an Anatomic Risk Factor for Anterior Cruciate Ligament Primary Injury and Secondary Graft Rerupture.

PURPOSE: To define the lateral femoral condylar angle (LFCA)-a parameter measuring condylar inclination-and assess its predictive capacity for primary and recurrent anterior cruciate ligament (ACL) injuries. METHODS: Patients aged 18 to 50&#x2009;years who underwent primary ACL reconstruction between 2017 and 2022 were screened. Those with graft rerupture were matched 1:1:1 by sex, age, body mass index, and meniscal status to ACL-intact controls and patients without graft failure during a minimum 48-month follow-up. LFCA was measured as the angle between the long axis of the distal femur and the axis of the lateral femoral condyle, alongside 38 established parameters using preoperative 3.0-T magnetic resonance imaging scans. Intergroup differences were assessed with one-way analysis of variance; multivariate regression and receiver operating characteristic analyses identified independent predictors and evaluated predictive performance. RESULTS: The study included 540 patients (180 per group: primary ACL injury, rerupture, controls). One-way analysis of variance revealed a significant gradient in LFCA across controls (81.3&#xb0;, 95% CI: 80.8-81.8&#xb0;), primary injuries (81.9&#xb0;, 95% CI: 81.5-82.3&#xb0;), and reruptures (84.2&#xb0;, 95% CI: 83.7-84.6&#xb0;) (P&#x2009;<&#x2009;.001). In multivariate models adjusted for baseline factors, LFCA independently predicted primary injury (odds ratio [OR]&#x2009;=&#x2009;1.27, 95% CI: 1.13-1.42, P&#x2009;<&#x2009;.001; area under the curve [AUC]&#x2009;=&#x2009;.576) and rerupture (OR&#x2009;=&#x2009;1.46, 95% CI: 1.21-1.76, P&#x2009;<&#x2009;.001; AUC&#x2009;=&#x2009;.704). Combined models incorporating LFCA with tibial slopes, notch angle, and notch height achieved an AUC of .847 for primary injury prediction, whereas models with LFCA, lateral condylar flexion curvature radius, slope asymmetry, and tibial AP distance reached an AUC of .817 for rerupture. LFCA alone with lateral condylar flexion curvature radius yielded an AUC of .777 for rerupture prediction. Sex-stratified analyses confirmed LFCA predicted rerupture in both male patients (OR&#x2009;=&#x2009;1.44, 95% CI: 1.19-1.75) and female patients&#xa0;(OR&#x2009;=&#x2009;1.49, 95% CI: 1.16-1.92), and primary injury in male patients&#xa0;(OR&#x2009;=&#x2009;1.30, 95% CI: 1.15-1.48). CONCLUSIONS: LFCA is an independent predictor of ACL injury, showing particular strength in identifying Asian patients at high risk for graft rerupture. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

Humans↗
PubMed1976

Fourier analysis of the cranium in trisomy 21.

A comparative study of individuals exhibiting the trisomy 21 syndrome (Down's) and a normal group has shown statistically significant differences in cranial shape (norma lateralis). These differences illustrate the departure from normal growth seen in individuals displaying the trisomy 21 syndrome. Fourier analysis is a preferred method since it is more efficient than conventional techniques in the analysis of complex shapes. Fourier analysis is also attractive because the series terms are orthogonal, hence independent; further, the Fourier approach allows for the control of size differences. A three-way analysis of variance was used to test for significant differences between mean Fourier coefficients. The results showed significant difference between individuals with trisomy 21 and controls. Age differences were also significant, only sex differences tended to be non-significant. Finally, the trisomy 21 sample is twice as variable as the controls.

Age Factors↗
PubMed1975

A double logistic comparison of growth patterns of normal children and children with Down's syndrome.

A double logistic model was used to compare six parameters of growth in standing height of 31 children with Down's syndrome with 136 children from the California Guidance Study. Multivariate analysis of variance of the growth data showed that while there were significant differences in all six parameters favouring the normal over the Down's children, there were no significant differences with respect to error of fit. Multivariate analysis with final height as a covariate revealed that differences between the normal and the Down's children in the prepubertal and adolescent components were explainable by differences in final height. In summary, the double logistic model, when applied to this sample of Down's children, identified those well defined logistic components which are characteristic of the growth of normal children, the differences being those of degree, not of form.

Analysis of Variance↗