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PubMed2005

[Determination and correlation analysis of trace elements in hair of dependence drug addicts].

The concentrations of Al, Ba, Ca, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr and Zn in the human hair of dependence drug addicts and healthy contrast were determined by ICP-AES. The RSD of the method was 1.3%-4.9%, and recovery was 89%-129%. Correlation of the trace elements was analyzed by SPSS software. The contents of Zn and Ca in the hair of dependence drug addicts were lower, while those of Pb, Fe and Mg were higher than healthy contrasts. The result provided a foundation for improving immune function of dependence drug addicts and enhancing the effect of giving up taking addictive drugs.

Adolescent↗
PubMed1980

[Correlation analysis of free mammary gland stroma cells during age-associated reorganization and spontaneous tumor development].

The cell content of mammary stroma infiltrate (lymphocytes, plasmocytes, eosinophilic leukocytes, macrophages, mast cells) was determined in the process of physiological involution, in dyshormonal hyperplasia and mammary gland tumours of old rats. Studies on the physiological involution revealed the existence of correlations between some pairs of the test types of free cells. Under dyshormonal transformation and tumour growth the former correlations disappeared and the new ones were formed, not occurring during the physiological involution of the mammary gland epithelium.

Adenofibroma↗
PubMed2005

[Correlation analysis between antipsychotic prescription quality and clinical status of patients with schizophrenia].

OBJECTIVE: The aim of this study is to describe the psychopharmacological aspects of psychiatric practice in a group of schizophrenic patients and to evaluate whether or not practice agrees with treatment guidelines. The study also intends to objectively measure the psychopathological state of patients in order to establish correlation between different pharmacological aspects of treatment and their clinical outcomes. METHOD: We have elaborated six recommendations concerning the pharmacological treatment of schizophrenia, taken from several guides, which are based on evidence. The psychopathological state of patients has been evaluated with the Brief Psychiatric Rating Scale (BPRS) and real prescription practice has been analysed. BPRS rates are compared depending on compliance with guidelines. RESULTS: More than 60% of patients do not comply with at least 4 of 6 evidence-based recommendations; compliance with recommendations being associated with a minor BPRS punctuation. Differences in BPRS punctuation between compliant and not compliant groups for 3 recommendations (maintenance antipsychotic dosage, antipsychotic association and drugs with a negative effect on cognitive functions), are statistically significant(p < 0,05; bilateral). DISCUSSION: Medical practice which closely follows treatment guidelines results in satisfactory clinical outcomes.

Adult↗
PubMed1992

Oestrogen receptor analysis: correlation between enzyme immunoassay and immunohistochemical methods.

AIMS: To compare oestrogen receptor measurements on fresh tissue done by an enzyme immunoassay (ER-EIA, Abbott) and an immunohistochemical technique (ER-ICA, Abbott) using formalin fixed, paraffin was embedded material. METHODS: The ER-EIA is based on a sandwich immunoassay using fresh frozen tissue, and the absorbance values were read by a Quantum Analyzer. Sections were cut from the corresponding paraffin wax blocks, and after pretreatment with pronase and DNase, the slides were incubated with monoclonal oestrogen antibody. The immunoperoxidase staining was scored semiquantitatively, incorporating both the intensity and percentage of positive staining (HSCORE). RESULTS: HSCORE rating of the ER-ICA slides gave a significant correlation with the quantitative ER-EIA values (r = 0.76; p less than 0.001). The overall sensitivity and specificity of the immunohistochemical method was 88% and 93%, respectively. CONCLUSIONS: ER-ICA on routinely processed material can be a valuable alternative when biochemical analysis of oestrogen receptor content is not available. Furthermore, immunohistochemical staining identifies oestrogen receptor positivity at a cellular level, which ensures that the analysed material is representative. This technique could therefore be particularly valuable in small tumours and in situ lesions.

Breast Neoplasms↗
PubMed1995

Correlational analysis of fictive swimming in the lamprey reveals strong functional intersegmental coupling.

1. Cycle-to-cycle fluctuations in cycle periods and intersegmental burst delays of ventral root activity were studied during stable fictive swimming in the adult lamprey spinal cord. High spatial resolution was obtained by recording from 16 ventral roots, 1/2 on each side of the spinal cord. For ipsilateral ventral roots, correlations between cycle periods on the same cycle were high (0.50 +/- 0.16, mean +/- SD), and autocorrelations of intersegmental delays with a shift of one cycle were low (0.03 +/- 0.06). Correlations between cycle periods tended to decrease with intersegmental spacing but remained positive over the range of spacings tested (1-47 segments). 2. Sinusoidal movement imposed on the caudal end of the spinal cord/notochord was used to entrain the fictive swimming rhythm. When the phase between the movement and the rhythm was perturbed, several cycles were required for the phase to return to its preferred value, indicating that in these experiments the effect of the movement was weak. In the absence of external perturbations, autocorrelations of delays between the movement and ventral root bursts with a shift of one cycle were high. 3. Numerical simulations with a simple stochastic phase model of the lamprey central pattern generator (CPG) were conducted. High correlations of periods and low autocorrelations of delays, the pattern observed experimentally, emerged as intersegmental connection strengths were increased. Coupling including both long and short connections produced this pattern of correlations with an average connection strength less than that required by short connections alone. 4. It is concluded that functional intersegmental coupling in the lamprey CPG during stable fictive swimming is strong. Specifically, the low autocorrelations of intersegmental delays indicate that intersegmental coupling is sufficiently strong to ensure that perturbations are almost completely corrected within one cycle.

Animals↗
PubMed1977

Age-specific correlation analysis of longitudinal blood pressure data.

To evaluate the predictive value of blood pressures for future levels, longitudinal measurements were analyzed among Welsh subjects from age 5 to 74 at entry. The measurements were taken on 863 individuals from the Vale of Glamorgan in 1956, 1960, 1964, and 1971 and on 734 individuals from the Rhondda Fach in 1954, 1958, 1964, and 1971. The tracking correlation, defined as the correlation between blood pressure readings on the same person taken at two different times, is used as a descriptive measure of the magnitude of the association. The tracking correlations range from 0.25 to 0.6-0.7 with most of the increases occurring before age 20. The tracking correlation depends on initial age, sex, and time interval between measurements. The age-specific tracking correlations decrease as time interval between measurements increases. For a given time interval, the age-specific correlations are slightly higher for females than for males. These findings are very similar for each of the two regions studied.

Adolescent↗
PubMed1999

Sexual dysfunction in multiple sclerosis: II. Correlation analysis.

Sexual dysfunction affects a large part of patients suffering from multiple sclerosis, but some aspects of its clinical presentation and aetiology are not clearly defined yet. In an unselected sample of 108 patients with definite multiple sclerosis we investigated the relationship between symptoms of sexual dysfunctioning and sphincteric dysfunction, patients' and disease characteristics, disability and neurological impairment, psychological and cognitive functioning. Sexual dysfunction directly correlated with presence of physical disorders (r=0.37, P=0.0004), low educational level (r=0.32, P<0.002), disability (r=0.31, P<0.003), age at onset of symptoms (r=0.30, P<0.003), sphincteric dysfunction (r=0.30, P<0.003), age (r=0.30, P<0.004), depression (r=0.29, P<0.005), fatigue (r=0.29, P=0.005), cognitive deterioration (r=0.26, P<0.01), primary-progressive course of disease (r=0.25, P<0.02), neurological impairment (r=0.25, P<0.02), marriage (r=0.24, P<0.02), anxiety (r=0. 23, P<0.03), male gender (r=0.22, P=0.03) bladder dysfunction (r=0. 29, P<0.04), and unemployment (r=0.21, P<0.04). Sexual dysfunction correlated inversely with relapsing - remitting course of disease (r=-0.31, P<0.002). No correlation was found between sexual dysfunction and bowel dysfunction, duration of disease, secondary-progressive course of disease, number and frequency of sexual intercourses in the last year, number of partners, number of exacerbations in the last year, number of months since last exacerbation, masturbation, and fertility. In conclusion, the association between sexual dysfunction and sphincteric dysfunction indicates a common aetiology corresponding to the frequent involvement of the spinal cord in multiple sclerosis, but the concomitant correlation between sexual dysfunction and other variables suggests the possible aetiological role of physical, psychological and sociological factors as well.

Adult↗
PubMed1987

Correlation analysis of muscle receptor discharge during active contractions of the cat medial gastrocnemius muscle.

The spike trains of afferent fibers innervating muscle spindles and Golgi tendon organs in the medial gastrocnemius muscle were recorded during spontaneous contractions in either decerebrate cats or decapitate cats treated with L-dopa. For each afferent fiber, the approximate location of its receptor within the muscle was determined. Cross-correlation histograms were compiled from the simultaneously recorded spike trains of pairs of afferent fibers (Ia, Ib, spindle II) to determine if the degree of temporal correlation in their discharge was related to the mutual proximity of the receptors they innervated within the muscle. The frequency of occurrence and degree of correlated activity between pairs of muscle afferents, regardless of receptor type, was much greater in the decerebrate preparations than in the decapitate-L-dopa preparations. However, in all cases, the extent of correlated activity appeared to be unrelated to the relative locations of the receptors. The results suggest that the degree to which the discharge patterns of muscle receptors display temporal correlations and thereby potentially reinforce the "sensory partitioning" (5) of their parent muscle is strongly dependent on the type of preparation used, and thus by inference, dependent on the central state of the animal.

Afferent Pathways↗
PubMed2000

Separation of arteries and veins in 3D MR angiography using correlation analysis.

Multiphase contrast-enhanced 3D MR angiography (MRA) data sets allow the separate visualization of the arterial and venous pulmonary vasculature. However, due to short arterial-to-venous bolus transit times in the lung, the generation of pure venograms without arterial overlay is difficult. To suppress arterial signal in venograms, early arterial phase data are typically subtracted from peak venous phase images. In this study, a correlation algorithm is used to postprocess the multiphase 3D MRA data sets. The cross-correlation between a measured arterial or venous reference function and the local signal-time course is computed which highlights image locations with a similar signal-time curve as the reference function and suppresses constant signal. Conventional maximum intensity projections (MIP) are generated from the arterial and venous correlation maps. In a study with five volunteers, an increase in SNR by a factor of 2.1 (1.8) of arterial (venous) correlation MIP images over subtraction MIP images was observed.

Contrast Media↗
PubMed1994

Neural modeling of the dorsal cochlear nucleus: cross-correlation analysis of short-duration tone-burst responses.

A conceptual model of a portion of dorsal cochlear nucleus (DCN) neural circuitry has emerged over the past two decades. This model suggests that the response properties of the DCN's major projection neurons, called type IV units, are due, in part, to the behavior of local circuit inhibitory interneurons called type II units (Young and Brownell 1976). Cross-correlation studies of simultaneously recorded pairs of DCN units in decerebrate cat derived from 50-s best frequency (BF) stimuli are consistent with and have extended this conceptual model (Voigt and Young 1980, 1985, 1988, 1990). Interestingly, Gochin et al. (1989) found no signs of inhibition in the anesthetized rat DCN in cross-correlograms derived from 55-ms short-duration BF tone bursts. This seemingly contradictory result has motivated this study. Computer simulations were run using our network model of the intrinsic DCN neural circuitry. This model has previously been shown to reproduce the major features of both type II and type IV rate-level curves and the inhibitory trough (IT) observed in cross-correlograms derived from long-duration stimuli (Voigt and Davis 1994). The goal was to study the stimulus-duration-dependent strength of ITs in the cross-correlograms derived from short-duration BF tone-burst stimuli. The results suggest that ITs may not be detectable when the stimulus duration is 50 ms but may be detectable when the stimulus duration is 200 ms or greater. Furthermore, when the ITs are detected in cross-correlograms derived from 200-ms data sets, the strength of the IT, as measured by effectiveness, is comparable to the strength of ITs measured when the stimulus duration is 50 s.

Acoustic Stimulation↗
PubMed1981

Spatio-temporal cross-correlation analysis of catfish retinal neurons.

1. The receptive field properties of visual neurons in the retina of the catfish are studied by a white noise spatio-temporal stimulus. The spatial and temporal inputs of the stimulus are independent and lead to complete linear characterizations and local nonlinear characterizations of the neural response. 2. Horizontal cells, bipolar cells, and sustained or Type N amacrine cells all yield spatially coherent linear correlations. The horizontal cells have the shortest latency by these methods and exhibit a late depolarizing component that is wider in spatial extent than the initial hyperpolarizing component. Depolarizing Type N neurons have center-hyperpolarizing local nonlinearity. 3. Transient or Type C amacrine cells do not correlate well with the intensity of the stimulus, even though the Fast variety responds vigorously to the stimulus. 4. Ganglion cells are classified into Excitatory, Inhibitory and biphasic classes based upon their linear correlations. Some ganglions exhibit responses dependent upon the orientation of stimulus. Although linear correlation of the Excitatory class is similar to that of the depolarizing Type N cell, the locally nonlinear character of these cell types is distinct. The receptive field of the inhibitory ganglion cells has strong locally excitatory nonlinearity.

Animals↗
PubMed1997

Neural interaction between cortical taste neurons in rats: a cross-correlation analysis.

In the rat cortical taste area (CTA), we recorded 31 pairs of taste neurons and seven pairs of taste and non-taste neurons, with single or double electrodes. By using a cross-correlogram (CCG) in a stationary state, we examined the functional interaction between neurons of the pairs while activating them by taste stimulation. Though only 14.3% of the taste and non-taste neuron pairs were correlated, 54.8% of the taste neuron pairs showed correlated activities, 41.9% of them showing common inputs, including one with an additional excitatory connection. The remainder (12.9%) showed excitatory connections with a time lag of 1-3 ms. When pairs were recorded using single or double electrodes with an intertip distance of < 50 microns in a dorsoventral direction, a larger fraction had correlated activities than when the intertip distance was > 50 microns. Whereas pairs of neurons showed correlated activities in area DI whatever the vertical intertip distance was, most of the pairs having correlated activities in area GI were found within 50 microns of the vertical intertip distance. The taste profiles of common inputs to the pair were estimated on the basis of peak at time 0 in CCGs for various taste stimuli. The efficacy contribution of the source to target neurons tended to be larger when both had the same best stimulus. This tendency held true for pairs showing excitatory connections. Interlayer excitatory connections were also evident. It is concluded that a functional column with a diameter of 50 microns may present in the CTA in rats, and that information flow is larger between pairs of neurons with the same best stimulus.

Animals↗
PubMed2002

Correlative analysis of lateral vertebral radiographic variables and medical outcomes study short-form health survey: a comparative study in asymptomatic volunteers versus patients with low back pain.

This prospective comparative study was designed to investigate the possible link between SF-36 functional status and lateral roentgenographic variables of the standing lumbar spine in patients with low back pain (LBP) versus asymptomatic volunteers. To the authors' knowledge, no previous studies have correlated SF-36 scores and sagittal roentgenographic variables in patients with LBP versus asymptomatic individuals. A total of 100 male volunteers, used as controls, and an equal number of age-, height-, and weight-comparable patients of the same ethnicity with chronic LBP were compared on the basis of roentgenographic and SF-36 data. The roentgenographic variables that were measured included the following: lumbar lordosis, sacral inclination, L1-S1 vertebral inclination, L4-S1 distal lordosis, disc index, and L1-L5 vertebral index. These variables were correlated with the eight SF-36 scales both in patients and controls. As the patients with LBP get older, they show lower functional scores in Role-Emotional (p < 0.01) and Physical Functioning (p < 0.01). Body height was not found to be a predisposition favoring LBP, but tall patients with LBP showed less Bodily Pain than patients of short stature (p < 0.001). This study showed that patients with LBP had significantly lower scores than their asymptomatic counterparts in the following SF-36 scales: Role-Physical (p < 0.01), Bodily Pain (p < 0.01), Role-Emotional (p = 0.058), and Mental Health (p < 0.001). In the controls General Health, Physical Functioning, Social Functioning, and Role-Emotional, Bodily Pain, Mental Health, and Vitality correlated statistically significantly with individuals' age, height, weight, lumbar lordosis, sacral inclination, inclination of L1, L3, and L5 vertebra, L1-L5 vertebral index, and L1-L2, L2-L3, L3-L4, L4-L5, and L5-S1 disc index. For the patients with LBP this study showed that General health, Physical Functioning, Role-Emotional, Social Functioning, and Bodily Pain were significantly correlated with age, height, L1-L2 inclination, distal lordosis, L2-L5 index, and L4-L5 and L5-S1 disc index. This comparative study showed that the functional status of hard-working patients with chronic LBP is associated with degenerative changes on the lateral radiographs of the lumbosacral spine. Spine surgeons should take into consideration the results of this study in reconstruction of painful degenerative lumbosacral spine.

Adult↗
PubMed1992

Age-specific correlation analysis of longitudinal physical fitness levels in men.

This study investigated the age-specific tracking of adult health- and performance-related fitness scores. In addition, the independent contribution of adolescent physical characteristics to the explanation of adult fitness scores was also studied. The sample consisted of 173 adults observed at age 30 years. These subjects had been followed at annual intervals from age 13 to age 18 years and were remeasured at age 30 years. At each age nine fitness tests were administered together with the recording of anthropometric dimensions, biological maturation, sports participation and family characteristics. Tracking was measured by the inter-age correlations at each age between 13 and 18 years and the performance scores at 30 years. The independent contribution of characteristics observed during adolescence to the explanation of adult fitness was investigated through stepwise multiple regression analysis and discriminant analysis with the adult fitness scores as the dependent variables and the fitness, maturation, anthropometric characteristics, sports participation and family background as the independent variables. Tracking between age 13 and age 30 years was moderately high (46% of variance explained) for flexibility, low to moderate (between 19% and 27% of variance explained) for the other fitness parameters and low for pulse recovery and static strength (7% to 11% of variance explained). Between age 18 and age 30 years the tracking was high for flexibility, moderately high for explosive and static strength, and moderate for the other fitness parameters except for pulse recovery. The amount of variance of adult fitness levels explained increased significantly when other characteristics observed during adolescence entered the regressions or discriminant functions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1975

Chromatographic hydrophobic parameters in correlation analysis of structure-activity relationships.

The use of RM and delta RM parameters as indices of hydrophobicity for inclusion in quantitative structure activity relationships has been studied. The relationship between these parameters and other free-energy related parameters is illustrated theoretically and experimentally. It is suggested that the chromatographically obtained parameters could find a wider applicability in structure-activity relationships, and that their use would result in improved correlation of data.

Absorption↗
PubMed1995

Disseminated, multiclonal Epstein-Barr virus-associated lymphoproliferative disease in a patient with hematological and immunological anomalies. Molecular analysis correlates with morphological appearance.

We report a case of a 21-year-old woman with hematopoietic, immunological, and congenital dysmorphic abnormalities, who died following rapidly progressive, disseminated Epstein-Barr virus (EBV)-associated lymphoproliferative disease (LPD). Polymerase chain reaction (PCR) amplification of formalin-fixed paraffin-embedded tissue showed differences in the clonality of each separate lymphoproliferative lesion examined, as determined by immunoglobulin heavy chain (IgH) gene rearrangement. PCR analysis also demonstrated that all lesions contained EBV genome. Since DNA had been extracted from paraffin blocks, a direct comparison of morphology and clonality could be made in each individual lesion. The evidence from this study indicates that the monoclonal tumors arose de novo in multiple sites and that the polyclonal background observed in some lesions reflected a substantial concomitant inflammatory response.

Blotting, Southern↗
PubMed1997

[Correlative analysis with proliferating cell nuclear antigen and bromodeoxyuridine on golden hamster carcinogenesis model]

The early diagnosis of carcinomatous conversion has special significance on increasing therapeutic effectivencess.Proliferating cell nuclearnatigen(PCNA),bromodexoyuridine(UrdU)(immunohistochemistry ways),and microscopic diagnosis were applied and observed on golden hamster cheek is pouch carcinogenisis model induced by dimethylbenzanthracene(DMBA) in order to seek simple,effective,leading and reliable diagnostic way.The results showed that three observable means had significant correlativity,and demonstrated that immunohistochemistry ways have practical value in diagnosis of carcinomatous conversion.This study suggests that PCNA and BrdU be more sensitive,simple and reliable,and hopeful methods of early diagnosis of carcinomatous conversion.

Journal Article↗