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PubMedDate not supplied

[Diagnostic possibilities and limits of 4-electrode rheoencephalography in premature infants with risk of brain damage].

Diagnostic value of cerebral electrical impedance for recognizing the risk of cerebral damage was analysed in 63 premature infants with postnatal respiratory disturbance during the first 4 weeks of life. Relationship between clinical risk factors like gestational age, Apgar scores, blood gas values on the one hand and impedance parameter of pulse volume, flow velocity and periphereal vascular resistance on the other were studied by means of correlation as well as variance analysis. Decrease of gestational age, Apgar score and increasing severity of respiratory disturbance cause statistically significant lowering of impedance parameters indicating reduction of volume, flow velocity and periphereal resistance in cerebral circulation by extreme immaturity, serious asphyxia as well as idiopathic respiratory distress syndrome. On contrast no statistically significant difference could be found between infants with and without intraventricular haemorrhages. However, significant differences were seen between group of patients only. Because of intercorrelation of risk factors and distinct variance no critical level of impedance parameters could be defined for the individual patient.

Asphyxia Neonatorum↗
PubMed1988

Determination of U in human tissues by delayed neutron activation analysis.

A rapid, sensitive and highly selective technique using Delayed Neutron Activation Analysis (DNAA) has been used to determine U concentrations in human tissues. Two different sample preparation techniques were compared: one involves total matrix destruction to a dry ash while the other is a nondestructive preparation of the wet sample. The data obtained from the analyses of the same sample by DNAA of wet tissues, DNAA of ashed tissues and from radiochemical analyses using alpha spectroscopy (a standard method of U determination) were statistically equivalent on the basis of variance analysis at the p = 0.05 level.

Activation Analysis↗
PubMed2005

[Dynamics of soil properties under secondary succession forest communities in Mt. Jinyun].

Mt. Jinyun is located in the north suburb of Chongqing, 30 km away from the city center. It is rich in forest plants, an epitome of forests in north tropical areas of China. Under anthropocentric disturbance, there still exist large numbers of succession communities, and the process of successive development follows the way of shrub-grassland (X1)-->coniferous forest (X2)-->coniferous-broad leaved mixed forest (X3)-->evergreen broad-leaved forest (X4). By now, soil and water conservation is very important in the Three Gorges area of Yangtze River, and the investigation on the secondary succession of the forests could help to realize the changes of the forests and soils under anthropocentric disturbance, and supply information on the protection of natural forests and the artificial reforestation of this area. In this paper, some typical and representative plant communities in different succession stages were selected to study the plant composition and type and the soil properties, with species diversity indices and canopy density investigated in many standard squares and soil physical and chemical characteristics analyzed. The results showed that there were obvious variations of soil properties with time. As the plant community developed from primary stage to climax, the contents of soil organic matter, total N, and available N and K increased in order of X1 < X2 < X3 < X4, soil pH changed from 5.23 (X1) to 4.06 (X4), soil base saturation varied from 58.3% (X1) to 37.7% (X4), and soil CEC increased with the succession. It was suggested that an intense soil acid leaching was occurred in Mt. Jinyun. The contents of soil organic matter and total N in different layers showed a trend of A>B>C, e. g., soil total nitrogen in evergreen broad leaved forest was 2.31(A), 0.66(B) and 0.12(C)g x kg(-1). Gray analysis was used to study the relationships of soil properties between the climax community and other three succession communities. The relation coefficient was 0.461 0 (X3), 0.586 2(X2) and 0.6821 (X1), respectively, indicating that soil nutrients were accumulated as the forest succession community progressed. The plant arbor species followed the sequence of 0 (X1) < 7.5 (X2) < 9.0 (X3) < 12.8 (X4), and the canopy density ranked as the same way. Plant community could affect soil nutrient reserves significantly. Multivariate variance analysis showed that soil properties varied significantly among different seasons, but this variation had no impact on the community replacement and soil development during the chronosequence of community succession. The variation of soil properties adapted well to each successive community.

China↗
PubMed1996

Is there a suicidality syndrome independent of specific major psychiatric disorder? Results of a split half multiple regression analysis.

Biological findings such as low 5-HIAA levels in cerebrospinal fluid (CSF) in suicidal patients compared to non-suicidal patients independent of the type of psychiatric disorder indicate a broad basis for suicidality. It is therefore important to ask whether a suicidality syndrome can be delineated on a phenomenological level, and whether it is independent of specific major psychiatric disorders which are otherwise considered to be aetiologically different. This paper reports on a study of 2383 schizophrenic and 1920 depressive unselected patients with and without suicidality. They were assessed during the first 24 h after admission to a psychiatric in-patient facility using a comprehensive psychopathological assessment (AMDP system). Using multiple variance analysis and logistic regression analysis based on single symptoms, for both suicidal and non-suicidal patients it was shown that a suicidality syndrome independent of the underlying illness can be delineated. In schizophrenia as well as in major affective disorders it was found that hopelessness, ruminative thinking, social withdrawal and lack of activity are core symptoms of this suicidal syndrome. The finding of a suicidality syndrome, not associated with a specific major affective disorder, indicates the need to identify this syndrome, which should be seen as an independent dimension and diagnosed separately, and not regarded merely as a secondary symptom of major psychiatric disorders, particularly affective disorders.

Adult↗
PubMed2000

Quantitative genetic analysis of circulating levels of biochemical markers of bone formation.

Carboxyterminal propeptide of type 1 collagen (PICP) and bone Gla-protein-osteocalcin (BGP) are the most important components of the organic bone matrix and play a key role in bone formation. To investigate whether and to what extent variation of the plasma levels of these indices of bone turnover depends on genetic factors, we studied 355 adults belonging to nuclear pedigrees. Genetic analysis was carried out in 2 steps: 1) variance decomposition analysis was performed using the FISHER statistical package; and 2) complex segregation analysis implemented in the program package MAN. The effect of age and gender differences, gender hormones, as well as PTH and vitamin-D (calcidiol) plasma levels were evaluated simultaneously with the parameters of variance analysis. The results showed that about 50% of PICP variation is attributable to genetic factors. The effect of age was significant among men and postmenopausal women, whereas calcidiol influenced variation of PICP in premenopausal women. The results of variance analysis showed that some 40% of BGP, adjusted for confounding variables, can be explained in genetic factors. Age and PTH were important covariates for osteocalcin in men and premenopausal women. Exploration of the maximum likelihood estimates of the various hypotheses concerning the mode of intergenerational transmission of PICP and BGP demonstrated a good correspondence to the Mendelian mode of inheritance (i.e., major gene effect).

Adolescent↗
PubMed1992

[Significant bacteriospermia. Value and limits of sperm count in andrology].

The data concerning bacteriospermia--are very different in the literature. Asymptomatic andrologic patients, and as control group--patients of the outpatient department for male adnexitis--were studied. Cultivation of aerobic bacteria and mycoplasmas has been recently accomplished by quantitative bacteriological analysis and chlamydia diagnostic. The microbiological screening of 210 andrologic patients ejaculate has given the following results: 19.6% were sterile, 21.0% were colonised by apathogens, 59.1% were positive: 6.2% Mycoplasma hominis, 15.8% Ureaplasma urealyticum, 13.3% Chlamydia trachomatis, 51.9% other aerobic pathogens. 27.6% of samples contained more then one kind of bacteria strains. Quantitative isolation of aerobics and mycoplasmas in both andrological and male adnexitis patients groups showed the following distribution. In the andrologic groups 14.7% of samples contained 10(4) CFU/ml, 9.6% more than 10(4) CFU/ml aerobic bacteria; in the male adnexitis group nearly twice higher values could be observed (20.2% and 19.5%). The distribution of mycoplasma CFU/ml was the following; andrologie group: 20.1% of samples contained 10(4) mycoplasma CFU/ml, 37.5% more than 10(4) CFU/ml; in the male adnixitis group the identical values: 22.9%, 66.9%. Chi 2 statistical analysis showed significant difference ((p = 0.000) in the distribution of data in the two groups. On the other hand both of the groups contained all kinds of bacteriological concentration and even negative cases. Therefore authors suggest more biochemical investigations for detecting inflammatory diseases. Spermaparameters (motility and progressive motility) of andrological patients, divided by sperm concentration (cell number above and under 20 million/ml) and the degree of infection (non infected, slightly infected, and above 10(4) CFU/ml) were significantly different in the seriously infected group by variance analysis (p = 0.000).

Bacterial Infections↗
PubMed2006

Alignment and statistical difference analysis of complex peptide data sets generated by multidimensional LC-MS.

A method for high-resolution proteomics analyses of complex protein mixtures is presented using multidimensional HPLC coupled to MS (MDLC-MS). The method was applied to identify proteins that are differentially expressed during fruit ripening of tomato. Protein extracts from red and green tomato fruits were digested by trypsin. The resulting highly complex peptide mixtures were separated by strong cation exchange chromatography (SCX), and subsequently analyzed by RP nano-LC coupled to quadrupole-TOF MS. For detailed quantitative comparison, triplicate RP-LC-MS runs were performed for each SCX fraction. The resulting data sets were analyzed using MetAlign software for noise and data reduction, multiple alignment and statistical variance analysis. For each RP-LC-MS chromatogram, up to 7000 mass components were detected. Peak intensity data were compared by multivariate and statistical analysis. This revealed a clear separation between the green and red tomato samples, and a clear separation of the different SCX fractions. MS/MS spectra were collected using the data-dependent acquisition mode from a selected set of differentially detected peptide masses, enabling the identification of proteins that were differentially expressed during ripening of tomato fruits. Our approach is a highly sensitive method to analyze proteins in complex mixtures without the need of isotope labeling.

Cation Exchange Resins↗
PubMed1995

Multivariate genetic analysis of Wechsler Intelligence Scale for Children--Revised (WISC-R) factors.

Wechsler Intelligence Scale for Children--Revised (WISC-R) factor scores (Verbal Comprehension, Perceptual Organization, and Freedom from Distractibility) were obtained from 574 twin pairs in the Colorado Reading Project and subjected to multivariate genetic analysis. Variances were partitioned into components common to the three WISC-R factors and to those specific to each factor. Substantial commonality, both genetic and environmental, was found among the three factors. The full model fit the data well, and estimates of heritability and environmentality indicated that about half of the phenotypic variance for each factor is due to additive genetic effects. These results were compared to those obtained in a previous twin study of the three Wechsler Adult Intelligence Scale (WAIS) factors by Tambs et al. (1986).

Adolescent↗
PubMed2006

Utilization of two sample t-test statistics from redundant probe sets to evaluate different probe set algorithms in GeneChip studies.

BACKGROUND: The choice of probe set algorithms for expression summary in a GeneChip study has a great impact on subsequent gene expression data analysis. Spiked-in cRNAs with known concentration are often used to assess the relative performance of probe set algorithms. Given the fact that the spiked-in cRNAs do not represent endogenously expressed genes in experiments, it becomes increasingly important to have methods to study whether a particular probe set algorithm is more appropriate for a specific dataset, without using such external reference data. RESULTS: We propose the use of the probe set redundancy feature for evaluating the performance of probe set algorithms, and have presented three approaches for analyzing data variance and result bias using two sample t-test statistics from redundant probe sets. These approaches are as follows: 1) analyzing redundant probe set variance based on t-statistic rank order, 2) computing correlation of t-statistics between redundant probe sets, and 3) analyzing the co-occurrence of replicate redundant probe sets representing differentially expressed genes. We applied these approaches to expression summary data generated from three datasets utilizing individual probe set algorithms of MAS5.0, dChip, or RMA. We also utilized combinations of options from the three probe set algorithms. We found that results from the three approaches were similar within each individual expression summary dataset, and were also in good agreement with previously reported findings by others. We also demonstrate the validity of our findings by independent experimental methods. CONCLUSION: All three proposed approaches allowed us to assess the performance of probe set algorithms using the probe set redundancy feature. The analyses of redundant probe set variance based on t-statistic rank order and correlation of t-statistics between redundant probe sets provide useful tools for data variance analysis, and the co-occurrence of replicate redundant probe sets representing differentially expressed genes allows estimation of result bias. The results also suggest that individual probe set algorithms have dataset-specific performance.

Algorithms↗
PubMed1995

[Social assessment of anxiety in primary health care].

OBJECTIVE: Identification of the social profile of our anxious patients, and analysis of the usefulness of Bell's questionnaire for our area of work. DESIGN: A retrospective observation study of a crossover type. SETTING: Primary Care. PARTICIPANTS: 55 patients who consulted their Family Doctor and were diagnosed as suffering from Anxiety. MEASUREMENTS AND MAIN RESULTS: We confirmed the diagnosis with the DSM-III-R and then analysed the level of Anxiety with the Hamilton Scale. The social evaluation was done by means of Bell's profile. As test statistics we used the lineal correlation Coefficient, the Student's t and Xi2 tests and Variance Analysis. 65% of diagnoses were Generalised Anxiety. The Hamilton mean was 20.9 points (S = 9.2). Overall social adaptation was unsatisfactory, with the worst results being for the emotional aspects. We observed a higher level of Anxiety as age increased (p = 0.021), related to a worse adaptation to Health (p = 0.014). Dissatisfaction with work and the working environment took the form of professional adaptation being poorer as their work situation deteriorated (p = 0.006). Anxiety levels were higher among the unemployed. Social adaptation was less among people with higher Anxiety levels (p = 0.04), above all as a consequence of worse adaptation to Health (p = 0.002) and worse emotional (p = 0.00001) adaptation. CONCLUSIONS: 1) We must introduce social aspects into analysis of patients with Anxiety. 2) Bell's profile enables us to identify those social aspects which can be tackled when caring for our patients. Its fundamental use is in individual application.

Adaptation, Psychological↗
PubMed1991

Reproducibility of electromyographic measures: a statistical analysis.

The masseter, temporalis anterior and digastric anterior muscles of five volunteers have been investigated by means of surface electromyography. Each muscle was tested by three operators at different times and under three distinct conditions of intermaxillary relationship: resting, with no occlusal contact (physiological rest position); occlusion in centric occlusion (C.O.) without clenching force; and maximum voluntary clench. In all the trials the BIO-PAK system (Bio-Research Associates Inc., Milwaukee, WI, USA) was used. Measurements were made in two consecutive experimental trials separated by an interval of about 15 days. In the first trial the operators had minimal instrumental experience, while in the second trial the same operators had minimal instrumental experience, while in the second trial the same operators had performed at least 30 measurements each. The data have been analysed by a factorial variance analysis, particularly with a view to comparing the variability between operators for each volunteer subject. The analysis revealed statistically significant differences only in the first experimental trial, due to the operators' lack of experience. The study demonstrates that the electromyographic system and protocol used allow good reproducibility of measurements. Furthermore, they have potential applications in both clinics and research.

Action Potentials↗
PubMed1989

Dose-related plasma levels of clozapine: influence of smoking behaviour, sex and age.

Drug monitoring in psychiatry is of increasing interest due to compliance problems, side effects of psychoactive drugs and the search for adequate dosage. In the present study, plasma levels of clozapine, as determined by high performance liquid chromatography, were investigated in 148 patients receiving a daily dose between 12.5 and 700 mg clozapine. Regression analysis revealed a linear relationship between dose and plasma concentrations. Plasma concentrations at a given dose (level divided by dose and body weight) in male patients reached only 69.3% of the concentrations in female patients (Mann-Whitney U Test P less than 0.001). When the patients were divided into smokers and non-smokers, the corresponding plasma levels were also found to be linearly dose dependent in each of the two groups. However, the average plasma concentration at a given dose was only 81.8% in smokers, compared to non-smokers. This difference was statistically significant (variance analysis P = 0.022). Dividing female patients into smokers and non-smokers, the smokers reached nearly the same plasma levels as the non-smokers. Male smoking patients reached average plasma concentrations which were only 67.9% of those of non-smokers. This difference was statistically significant (Mann-Whitney U Test P = 0.0083). The plasma levels of the different age groups at a given dose per kg body weight were compared using the Mann-Whitney U Test. Significant differences were found between group 1 (18-26) and group 4 (45-54) (P less than 0.01) and group 2 (27-35) and group 4 (P less than 0.01) showing higher plasma levels in the older age group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2004

A genome scan for eye color in 502 twin families: most variation is due to a QTL on chromosome 15q.

We have rated eye color on a 3-point scale (1 = blue/grey, 2 = hazel/green, 3 = brown) in 502 twin families and carried out a 5-10 cM genome scan (400-757 markers). We analyzed eye color as a threshold trait and performed multipoint sib pair linkage analysis using variance components analysis in Mx. A lod of 19.2 was found at the marker D15S1002, less than 1 cM from OCA2, which has been previously implicated in eye color variation. We estimate that 74% of variance in eye color liability is due to this QTL and a further 18% due to polygenic effects. However, a large shoulder on this peak suggests that other loci affecting eye color may be telomeric of OCA2 and inflating the QTL estimate. No other peaks reached genome-wide significance, although lods > 2 were seen on 5p and 14q and lods >1 were additionally seen on chromosomes 2, 3, 6, 7, 8, 9, 17 and 18. Most of these secondary peaks were reduced or eliminated when we repeated the scan as a two locus analysis with the 15q linkage included, although this does not necessarily exclude them as false positives. We also estimated the interaction between the 15q QTL and the other marker locus but there was only minor evidence for additive x additive epistasis. Elaborating the analysis to the full two-locus model including non-additive main effects and interactions did not strengthen the evidence for epistasis. We conclude that most variation in eye color in Europeans is due to polymorphism in OCA2 but that there may be modifiers at several other loci.

Chromosomes, Human, Pair 15↗
PubMed1992

[An analysis of heritability of intra-erythrocytic Na+, K+ in 139 twins].

By means of the twin model contributions of shared genes and shared environments for red blood cells Na+ and K+ were analysed by genetic and epidemiologic methods. Determination of zygosity was mainly based on examination of red blood cells system, including ABO blood group, MN blood group, P blood group, Rh blood group and secretor status of saliva, such that the probability a dizygotic pair being identical for all of these indices was less than 0.05. 139 pairs of twin in Nan Kai district Tianjin were investigated containing 74 pairs of monozygotic twins (MZ) and 65 pairs of dizygotic twins(DZ). Several methods of estimating genetic heritability (h2) were used, such as the three methods proposed by Vogel, the Holzinger's method. Levine's method based on model of variance analysis and path analysis. The degrees of compatibility of various h2 were also analysed. The contributions of shared genes, shared environments and twin's own special environments were similar for RBC Na+, h2 = 0.32, C2 = 0.35, u2 = 0.33. The contributions of shared environments were the main cause for RBC K+, C2 = 0.97.

Adolescent↗
PubMed2004

[Impact of cardiovascular illness on hospitalization costs in patients with rheumatoid arthritis].

The causes of admission and the distribution of direct medical costs were examined to establish the clinical predictors of high hospitalization costs in patients with rheumatoid arthritis. This retrospective study included all rheumatoid arthritis patients who were hospitalized in the Clínica Universitaria Bolivariana in Medellín, Colombia, between January 1999 and June 2003. Data were obtained from the medical records and from the hospital statistical section using a cost-analysis spreadsheet. A total of 41 patients were hospitalized 62 times (0.34 hospitalization per patient per year). Disease activity was the most important cause of admission (60%), followed by surgery (18%), and infection (10%). In 30 (48%) hospitalizations, at least one comorbidity was recorded, with cardiovascular disease being the most frequent (32%). The mean length of stay per patient was 5+/-6 days. The mean total cost was 1,277 US dollars, and the mean cost per day of hospitalization was 235 US dollars. Medications represented 54% of the total cost, whereas that representing medical care was only 3%. Variance analysis disclosed cardiovascular disease as the most important determinant of high costs (p<0.01). In conclusion, the direct costs for inpatients with rheumatoid arthritis were considerable, and arose mainly from organic complications. Prevention and treatment of cardiovascular disease are indispensable not only to reduce the economic burden of rheumatoid arthitis, but also to diminish the risk of mortality. These data assist in the estimation of health care resources and in the selection of public health policies for the improvement of patient outcomes.

Aged↗
PubMed2006

[Spatial heterogeneity of soil moisture in Shapotou sand-fixing artificial vegetation area].

To explore the characteristics of soil moisture heterogeneity in sand-fixing artificial vegetation area is of significance in vegetation recovery and environment control in arid regions. With the methods of traditional statistics and geo-statistics, this paper studied the heterogeneity of soil moisture in the layers from 0 to 200 cm in depth in Shapotou sand-fixing vegetation area. The results showed that the variation of soil moisture in layers of 160 to approximately 180 and 180 to approximately 200 cm was relatively larger, with the variation coefficient being 0.72 and 0.73, respectively, and the next was in top layer (0 to approximately 5 cm ), with a variation coefficient of 0.66. Semi-variance analysis showed that the autocorrelation of soil moisture spatial heterogeneity in total spatial heterogeneity was high, ranging from 87.7% to 99.9%. The scale of spatial heterogeneity in different soil layers was different, with the minimum in 60 to approximately 80 cm layer and the maximum in 20 to approximately 40 cm layer, but no regular changes being observed from surface to deep layers. The colorful contour maps of Kriging interpolation indicated that the variation of soil moisture was larger in 0 to approximately 140 cm layer than in 140 to approximately 200 cm layer. The correlation between semi-variance and distance in four directions of 0 degrees, 45 degrees ,90 degrees and 135 degrees was weak, suggesting that the variation of soil moisture was independent, random, and homogeneous.

Conservation of Natural Resources↗
PubMedDate not supplied

Morphometric analysis of the acromioclavicular joint.

The width of the articular space of the acromioclavicular (AC) joint was investigated to evaluate normal range values and any possible variations in relation to age and sex. Radiographs of the AC joints of 72 males and 28 female (age range: 38-83 yrs) were studied. The articular space width of the AC joint was measured using a semiautomatic computerized system. The measurements were performed bilaterally at the level of smallest distance between the articular surfaces in all the radiograms. The mean value of the articular space width was calculated for all the subjects as a single group, for that of the males and for that of the females. The films were then divided into four groups according to age (< 50; 50-59; 60-69; > 70 yrs) and the mean value per group was calculated. The values obtained were studied using variance analysis. No significant difference were found in the mean values of the articular space width when males and females were compared as regards to age. However, even if the articular space width diminished, in both sexes, with an increase in age, the differences between age classes were not statistically significant.

Acromioclavicular Joint↗
PubMed2001

Distribution of lod scores in oligogenic linkage analysis.

In variance component oligogenic linkage analysis it can happen that the residual additive genetic variance bounds to zero when estimating the effect of the ith quantitative trait locus. Using quantitative trait Q1 from the Genetic Analysis Workshop 12 simulated general population data, we compare the observed lod scores from oligogenic linkage analysis with the empirical lod score distribution under a null model of no linkage. We find that zero residual additive genetic variance in the null model alters the usual distribution of the likelihood-ratio statistic.

Chromosome Mapping↗