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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↗
PubMedDate not supplied

Blocked- and integrated-content baccalaureate nursing programs: a comparative study.

This study evaluated the differences between blocked- and integrated-content baccalaureate nursing programs related to faculty satisfaction, senior students' critical thinking ability, and students' state board examination performance. Faculty satisfaction had 10 factor scores--7 directly teacher-related factors and 3 indirectly teacher-related factors. Analysis of 85 faculty members by a one-dimensional, nested multivariate analysis of variance design revealed that faculty satisfaction was not a function of the type of content program. Analysis of 104 senior students by a one-dimensional, nested univariate analysis of variance design revealed no significant difference in critical-thinking ability between the two types of content programs. When 230 students' SBE scores were subjected to a one-dimensional, nested multivariate analysis of variance, blocked-content program students scored significantly higher than integrated-content program students. Recommendations for further study are made.

Analysis of Variance↗
PubMed1977

The use of analysis of covariance to increase precision wtih DMFS measures.

For an experimental study with pre- and post-DMFS measures two methods of analysis were compared with respect to precision. It is shown that for large sample size, the analysis of covariance with the post-DMFS measure as criterion and the pre-DMFS measure as the covariate will be more precise than the analysis of variance of increment scores as the value of beta differs from 1. When beta is approximately 1, the two techniques will have essentially the same precision. The dental researcher interested in precision is advised, therefore, to use analysis of covariance with the pre-DMFS measure as the covariate and the post-measure as criterion rather than the traditional analysis of variance of increment scores. For large sample size, the precision of the former will tend to be at least that of the latter. The researcher is not encouraged to use analysis of covariance with the increment as the criterion; if the procedure increases precision over analysis of variance of the increments, it merely indicates that analysis of covariance (with the post-measure as criterion) should have been used originally.

Analysis of Variance↗
PubMed1977

Susceptibility to motion sickness and ego closeness, ego distance as measured by the autokinetic response tendency.

This paper reports results from one phase in an ongoing study of the relationship between vestibular function and various aspects of personality, cognitive style and symptom formation in mental illness. In the experiment reported here a measure of autokinesis was shown to relate to motion sickness experience as judged by actual stimulation in a rotating chair. Low and intermediate sensitive subjects showed less autokinesis than the most motion sick individuals (two-way analysis of variance F = 5.735, P = 0.006). Males in this sample showed a significantly greater autokinetic tendency than females (two-way analysis of variance F = 6.995, P = 0.011).

Adult↗
PubMed1975

[The acidity and peptic activity of gastric juice in healthy children and in children suffering from cystic fibrosis (author's transl)].

The acid concentration and quantity, the pH and the peptic activity of the gastric juice were measured after stimulation with pentagastrin in 10 children with cystic fibrosis between the ages 2 and 12 years and in 20 healthy children of the same age group. Furthermore, the basal, maximal and peak volume outputs (BVO, MVO and PVO), the basal, maximal and peak acid outputs (BAO, MAO and PAO) and the basal, maximal and peak pepsin output (BPO, MPO and PPO) were determined. The statistical calculations were carried out with the help of partial hierarchical analysis of variance, comparison of regression curves, simple analysis of covariance and the t test. After stimulation with pentagastrin, the volume of the gastric juice, the acid quantity and the peptic activity were found to be dependent on age in healthy children as well as in children with cystic fibrosis. The maximal volume of secretion in children with cystic fibrosis is less than that of healthy children; however, the acid quantity and peptic activity show no significant difference in both groups. The volume of the gastric juice, acid quantity and peptic activity in basal and stimulated secretions, expressed in kilograms per body weight or surface area in square meters, are independent of age and show no significant difference between the two groups. In the two groups the curves for the three parameters differ significantly from one to another. There is a significant shift in the time course of the curves that depict the acid secretion and peptic activity. Contrary to the accepted views, the acid and enzyme secretions are not closely interrelated. Based on the acidity and peptic activity, the digestive capacity of the stomach is the same for healthy children and children with cystic fibrosis. In contrast to the pancreas, there is no impairment in the exocrine function of the stomach. The gastric secretions of children with cystic fibrosis are not completely the same as in healthy children.

Body Surface Area↗
PubMedDate not supplied

[Additional limitations of the Shrikhande method and their verification].

Shrikhande's method was checked on linear-variety common wheat Lutescens 62. Two causes for a distortion of the ratio of genotypic and paratypic components of the variance were established: parameter b of Smith's law is not constant for a given field and depends on the method of parcelling: Smith's law is not confirmed at all. A two-stage test of Shrikhande's method correctness is suggested for checking its limitations in practice. The analysis of variance for any given parcelling is done at the first stage. Significant ratios of between-cluster mean squares and within-cluster mean squares indicate that Smith's law is confirmed. The second stage consists in the analysis of variance of lg V(X) linear regression by lg X or in the graphical analysis of the function lg V(X) = = f (lg X).

Genetic Techniques↗
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↗
PubMed1979

A study of relationships between judgments of speech and appearance of patients with orofacial clefts.

A series of six studies was designed to examine the effects of subjects' appearance on listeners' judgments of nasal speech and to examine the effects of nasal speech on viewers' judgments of attractiveness. In three studies, pictures of male and female subjects with varying degrees of orofacial clefts were paired with tape-recorded speech samples with varying degrees of nasality, and judges rated speech acceptability. Results of two-way analysis of variance failed to support the idea that appearance has an effect on ratings of nasality. In three other studies, the same stimuli were used to examine the effects of nasal speech on judges' ratings of appearance. Results of a two-way analysis of variance indicated that nasality had an effect on ratings of appearance. As the severity of nasality increased, ratings of attractiveness decreased. Results imply that a decrease in nasality may enhance the way persons with cleft lips are perceived cosmetically.

Cleft Lip↗
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↗
PubMed1978

A contribution to the electron microscopic morphometric analysis of peripheral nerve.

Several aspects of data collection and analyses of peripheral nerve experiments employing light and electron microscopic morphometric techniques have not been adequately discussed in the literature. From statistical tests performed on nerve data, it was found that light compared with electron microscopic morphometry underestimates the number of small fibers. An optimum sampling strategy must take into account a potential bias toward small fibers introduced by measuring fibers from electronmicrographs. It must also take into account a potential bias introduced by the non-random distribution of nerve fibers of different sizes in nerves. These biases are offset by sampling a large enough number of fibers from large enough area electron micrographs. A method is presented for analysing periopheral nerve data using the nested analysis of variance. This requires first dividing the usual bimodal nerve fiber distribution into component normally distributed parts. The number of fibers in the two portions of a bimodal distribution must be considered in data analysis. Knowledge of the variances of parameters to be studied in any particular nerve is necessary for optimum sampling strategies.

Animals↗
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↗
PubMed1978

Anxiety and skin diseases.

The purpose of this investigation was to determine if a relationship exists between anxiety and skin diseases. It was hypothesized that subjects wtih different dermatoses would have different anxiety levels. Subjects with the following skin diseases were compared: atopic dermatitis, cystic acne, noncystic acne, tinea versicolor, and pityriasis rosea. Anxiety levels were measured by use of the State-Trait Anxiety Inventory (STAI). The STAI consists of two twenty-item self-report rating scales for two types of anxiety: A-State anxiety, which is transitory or situational, and A-Trait anxiety, which is chronic or an enduring personality trait. A one-way analysis of variance revealed significant differences between the aforementioned groups in both A-State and A-Trait anxiety, with the mean elevations highest in the subjects with disfiguring acne (cystic) and intolerably prurific eczema (atopic dermatitis).

Acne Vulgaris↗
PubMed2026

Microrna Expression in Aurelia aurita Metamorphosis.

INTRODUCTION: In animal taxa and jellyfish, the same genome encodes for the different phenotypes that characterize life stages that follow each other during ontogeny. This situation underscores the existence of profound regulation of genomic information at the epigenetic level. MicroRNAs are fundamental epigenetic regulators. The aim of this study is to evaluate the role of microRNA regulation during jellyfish metamorphosis and to explore the existence of evolutionarily conserved microRNAs. METHODS: Specimens belonging to the 4-metamorphosis stages of A. aurita (polyps, ephyra, young, and adult jellyfish) were bred and collected. The expression of 2,549 miRNAs for each stage was tested using microarray technology. The comparison of microRNA expression for each phase was performed using line plot analysis and Principal Component Analysis of variance (PCA), while the identification of microRNA clusters was performed via volcano plot analysis. RESULTS: A remarkable number of A. aurita miRNAs specifically hybridize with a human miRNA library. Each metamorphosis stage is characterized by a different level of expression of miRNAs: 1) Polyp vs. Ephyra stage: 128 upregulated, 2 downregulated; 2) Ephyra vs. Young stage: 2 upregulated, 135 downregulated; 3) Young vs. Adult stage: 69 upregulated, 6 downregulated. Specific functions inferred from known activities of corresponding miRNAs in higher animals (PubMed database) appear to be coherent with the correlated experimental model. DISCUSSION: Present results reveal that microRNAs with human homologs undergo specific expression changes throughout Aurelia aurita metamorphosis. This observation reinforces the hypothesis of a shared evolutionary origin of certain miRNA families between Cnidaria and Bilateria. The dynamic and stage-specific regulation pattern observed suggests that miRNAs play a key role in orchestrating the complex transitions involved in jellyfish development. These findings point to a broader conservation of epigenetic mechanisms, such as miRNA-mediated gene silencing, which may have emerged early in metazoan evolution and contributed to the regulation of cell differentiation and phenotype modulation. CONCLUSION: The present study highlights the importance of Aurelia aurita as a model for investigating miRNA-driven epigenetic regulation in non-bilaterian animals. The identification of human-homologous miRNAs provides novel insights into the evolutionary stability of the epigenetic machinery and suggests conserved regulatory functions across distant taxa. Although limited by the use of a human-based microarray platform, the data presented here lay a solid foundation for future studies employing sequencing and functional assays to further explore the role of miRNAs in cnidarian development and evolution.

Animals↗
PubMed1979

Amplitude of evoked potentials and degree of event-related desynchronization (ERD) during photic stimulation.

The variations in amplitude of visual evoked potentials (VEPs) and parallel changes in amount of event-related desynchronization (ERD) of the rhythmic activity within the alpha band were studied in central derivations of scalp EEG, in 10 normal subjects. Two methods were used to estimate the amplitude of VEPs in small groups of 10 responses: (1) inverse and matched filtering techniques; (2) two-way rank analysis of variance by the Friedman test. The two methods gave similar results and two groups, statistically different, emerged. The first, with large VEP amplitude, having at the same time large ERD, and the second, with small VEP amplitude and small ERD.

Adult↗
PubMed2005

Population structure and properties of Candida albicans, as determined by multilocus sequence typing.

We submitted a panel of 416 isolates of Candida albicans from separate sources to multilocus sequence typing (MLST). The data generated determined a population structure in which four major clades of closely related isolates were delineated, together with eight minor clades comprising five or more isolates. By Fisher's exact test, a statistically significant association was found between particular clades and the anatomical source, geographical source, ABC genotype, decade of isolation, and homozygosity versus heterozygosity at the mating type-like locus (MTL) of the isolates in the clade. However, these associations may have been influenced by confounding variables, since in a univariate analysis of variance, only the clade associations with ABC type and anatomical source emerged as statistically significant, providing the first indication of possible differences between C. albicans strain type clades and their propensity to infect or colonize different anatomical locations. There were no significant differences between clades with respect to distributions of isolates resistant to fluconazole, itraconazole, or flucytosine. However, the majority of flucytosine-resistant isolates belonged to clade 1, and these isolates, but not flucytosine-resistant isolates in other clades, bore a unique mutation in the FUR1 gene that probably accounts for their resistance. A significantly higher proportion of isolates resistant to fluconazole, itraconazole, and flucytosine were homozygous at the MTL, suggesting that antifungal pressure may trigger a common mechanism that leads both to resistance and to MTL homozygosity. The utility of MLST for determining clade assignments of clinical isolates will form the basis for strain selection for future research into C. albicans virulence.

Analysis of Variance↗
PubMed1978

Criterion-oriented grading system for preclinical operative dentistry laboratory course.

The object of this study was to evaluate instructor reliabilities when using empirical or traditional and criterion-oriented grading methods. To do so, 52 sample preparations made in plastic teeth by freshman dental students in the preclinical operative dentistry laboratory course were graded by 12 instructors. The preparations included those for amalgam, inlay, and gold foil restorations. The instructors were divided into two groups according to their teaching experience. Intraclass correlation coefficients were calculated by using a one way analysis of variance technique. The criterion method, in general, yielded greater intraclass correlation coefficients. The increase in the intraclass correlation coefficient was found to be significant at the alpha = 0.10 error level for all restorations judged by experienced instructors. The different degrees of increase in correlation may be attributed to the vary ing clinical biases of the instructors and the differences in the types of preparations.

Analysis of Variance↗