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At least 541 records · Page 30Linked to original sources

PubMed1997

Behavioral and neuroendocrine responses to m-chlorophenylpiperazine in subtypes of alcoholics and in healthy comparison subjects.

OBJECTIVE: The purpose of this study was to explore central serotonergic functions in subgroups of alcoholics and in healthy comparison subjects. METHOD: The mixed serotonin (5-HT) agonist/antagonist m-chlorophenylpiperazine (m-CPP) was administered to male alcoholic patients who were classified according to the criteria of von Knorring et al. as type I alcoholics (late onset) (N = 16) or type II alcoholics (early onset with antisocial traits) (N = 24) and to 22 healthy comparison subjects. Psychological, physiological, and neuroendocrine measures were obtained before and after the m-CPP infusion. RESULTS: m-CPP elicited subtype-related differential effects among the alcoholics; the type I alcoholics reported more anger and anxiety, and the type II alcoholics reported increased euphoria and a greater likelihood of drinking. The healthy comparison subjects exhibited a greater increase in plasma ACTH response to the m-CPP infusion than the alcoholics regardless of subtype. CONCLUSIONS: Differences in certain 5-HT receptor functions may explain some of the clinical characteristics that differentiate the type II and type I subgroups of alcoholic patients. Furthermore, alcoholics may have reduced sensitivity of 5-HT2C receptors in comparison with healthy subjects.

Adrenocorticotropic Hormone↗

PubMedDate not supplied

Evaluation of insomnia and daytime napping in Iranian Alzheimer disease patients: relationship with severity of dementia and comparison with normal adults.

OBJECTIVE: Alzheimer disease (AD) is among the most common and disabling diseases in adulthood, and it has been largely neglected in traditional societies like Iran. Exacerbation of AD symptoms creates many severe problems, especially in traditional Iranian extended families. One of these problems is insomnia, which can very significantly affect patients' family members because of disturbing insomnia-related behaviors. METHODS: The authors studied 53 patients with probable AD who had been interviewed for dementia and depression in the Neurology Clinic of Roozbeh Psychiatric Hospital (Tehran University of Medical Sciences). Excluding patients with overlapping multi-infarct dementia, 35 AD patients (22 men, 13 women) and 21 adults without dementia were studied as a comparison group (11 men, 10 women). RESULTS: There was a significant relationship between duration of informant-reported symptoms and severity of dementia with daytime napping and more daytime napping among AD patients than in the comparison group. There was also a significant relationship between cognitive decline and daytime napping in the comparison group. Our study showed a relationship between insomnia and aggression, between daytime napping and paranoid delusions; and between onset of insomnia and anxiety. The comparison group showed a significant relationship between depression and daytime napping. CONCLUSIONS: Daytime napping and insomnia are very common among Iranian AD patients, much more so than in normal adults. There is also a significant relationship among psychiatric symptoms, daytime napping, and insomnia, but it seems that daytime napping and insomnia in depressed AD patients are caused more by the progress of AD than by depression.

Aged↗

PubMed2000

Cross-sectional study of older outpatients with schizophrenia and healthy comparison subjects: no differences in age-related cognitive decline.

OBJECTIVE: Little is known about the progression of cognitive deficits in older, community-dwelling patients with schizophrenia, especially in comparison to healthy subjects. METHOD: The authors examined the relationship of age to performance on the Mattis Dementia Rating Scale in 116 outpatients with schizophrenia and 122 normal comparison subjects. Subjects ranged in age from 40 to 85 years. RESULTS: Dementia Rating Scale scores were lower in the schizophrenia group but correlated negatively with age in both groups, with no significant differences seen between the schizophrenia and normal comparison groups in slopes that depicted age-related variation. CONCLUSIONS: This cross-sectional study suggests a relatively stable long-term course of cognitive impairment in individuals with schizophrenia, with no evidence of faster cognitive decline in outpatients with schizophrenia than in normal comparison subjects.

Adult↗

PubMed2004

Appearance-related social comparisons: the role of contingent self-esteem and self-perceptions of attractiveness.

Two studies examined contingent self-esteem (CSE) and responses to appearance-related social comparisons. Study 1 was an experimental study in which women rated a series of advertisements from popular women's magazines. Study 2 employed an event-contingent diary recording procedure. In Study 1, women who were higher in CSE and lower in self-perceptions of attractiveness (SPA) experienced greater decreases in positive affect and greater increases in negative affect following the ad-rating task. Study 2 results supported a mediation model in which women who were higher in CSE felt worse after social comparisons because they made primarily upward comparisons. Overall, results suggest that appearance-related comparisons are more distressing for those who base their self-worth on contingencies and have lower self-perceived attractiveness.

Adolescent↗

PubMed1982

Serum quinidine determination: comparison of mass-spectrometric and extraction-fluorescence methods.

A comparison of two analytical methods of quinidine plasma determination--the modified extraction fluorometric method and the mass spectrometric method--was made. Plasma supplies collected at steady state from normal human volunteers participating in a bioavailability study were analyzed, using both methods. A total of 359 samples were analyzed. Comparison of both sets of values, by linear regression, yielded an r2 value of 0.84. The results of this comparison were consistent with the results reported by others, confirming that the commonly used extraction fluorometric method of quinidine determination is sufficiently accurate for monitoring quinidine plasma concentrations in the patient care setting, as well as for bioavailability comparisons between products.

Humans↗

PubMed2005

Paircomp, FamilyRelationsII and Cartwheel: tools for interspecific sequence comparison.

BACKGROUND: Comparative sequence analysis is an effective and increasingly common way to identify cis-regulatory regions in animal genomes. RESULTS: We describe three tools for comparative analysis of pairs of BAC-sized genomic regions. Paircomp is a tool that does windowed (ungapped) comparisons of two sequences and reports all matches above a set threshold. FamilyRelationsII is a graphical viewer for comparisons that enables interactive exploration of several different kinds of comparisons. Cartwheel is a Web site and compute-cluster management system used to execute and store comparisons for display by FamilyRelationsII. These tools are specialized for the discovery of cis-regulatory regions in animal genomes. All tools and their source code are freely available at http://family.caltech.edu/. CONCLUSION: These tools have been shown to effectively identify regulatory regions in echinoderms, mammals, and nematodes.

Algorithms↗

PubMed2006

Algebraic comparison of metabolic networks, phylogenetic inference, and metabolic innovation.

BACKGROUND: Comparison of metabolic networks is typically performed based on the organisms' enzyme contents. This approach disregards functional replacements as well as orthologies that are misannotated. Direct comparison of the structure of metabolic networks can circumvent these problems. RESULTS: Metabolic networks are naturally represented as directed hypergraphs in such a way that metabolites are nodes and enzyme-catalyzed reactions form (hyper)edges. The familiar operations from set algebra (union, intersection, and difference) form a natural basis for both the pairwise comparison of networks and identification of distinct metabolic features of a set of algorithms. We report here on an implementation of this approach and its application to the procaryotes. CONCLUSION: We demonstrate that metabolic networks contain valuable phylogenetic information by comparing phylogenies obtained from network comparisons with 16S RNA phylogenies. The algebraic approach to metabolic networks is suitable to study metabolic innovations in two sets of organisms, free living microbes and Pyrococci, as well as obligate intracellular pathogens.

Algorithms↗

PubMed2006

Satisfaction of patients hospitalised in psychiatric hospitals: a randomised comparison of two psychiatric-specific and one generic satisfaction questionnaires.

BACKGROUND: While there is interest in measuring the satisfaction of patients discharged from psychiatric hospitals, it might be important to determine whether surveys of psychiatric patients should employ generic or psychiatry-specific instruments. The aim of this study was to compare two psychiatric-specific and one generic questionnaires assessing patients' satisfaction after a hospitalisation in a psychiatric hospital. METHODS: We randomised adult patients discharged from two Swiss psychiatric university hospitals between April and September 2004, to receive one of three instruments: the Saphora-Psy questionnaire, the Perceptions of Care survey questionnaire or the Picker Institute questionnaire for acute care hospitals. In addition to the comparison of response rates, completion time, mean number of missing items and mean ceiling effect, we targeted our comparison on patients and asked them to answer ten evaluation questions about the questionnaire they had just completed. RESULTS: 728 out of 1550 eligible patients (47%) participated in the study. Across questionnaires, response rates were similar (Saphora-Psy: 48.5%, Perceptions of Care: 49.9%, Picker: 43.4%; P = 0.08), average completion time was lowest for the Perceptions of Care questionnaire (minutes: Saphora-Psy: 17.7, Perceptions of Care: 13.7, Picker: 17.5; P = 0.005), the Saphora-Psy questionnaire had the largest mean proportion of missing responses (Saphora-Psy: 7.1%, Perceptions of Care: 2.8%, Picker: 4.0%; P < 0.001) and the Perceptions of Care questionnaire showed the highest ceiling effect (Saphora-Psy: 17.1%, Perceptions of Care: 41.9%, Picker: 36.3%; P < 0.001). There were no differences in the patients' evaluation of the questionnaires. CONCLUSION: Despite differences in the intended target population, content, lay-out and length of questionnaires, none appeared to be obviously better based on our comparison. All three presented advantages and drawbacks and could be used for the satisfaction evaluation of psychiatric inpatients. However, if comparison across medical services or hospitals is desired, using a generic questionnaire might be advantageous.

Adult↗

PubMed2006

Maternal attributions, affect, and parenting in attention deficit hyperactivity disorder and comparison families.

The goal of this study was to simultaneously examine maternal attributions, affect, and parenting in mothers of children with and without attention deficit hyperactivity disorder (ADHD) using a multimethod approach (vignettes, confederate child video clips, and video clips of mother's own child). Of the participants, 23 were 7- to 12-year-old children (19 boys, 4 girls) with ADHD and their mothers, and 29 were 7- to 12-year-old comparison children (21 boys, 8 girls) and their mothers. Results indicated that mothers of children with ADHD attributed inattentive-impulsive behavior to less controllable and intentional factors and reported more negative affect and power assertive parenting in response to it than comparison mothers. They also attributed this behavior to more internal factors than comparison mothers but only when viewing their own children and to more global/stable factors but only when viewing their own children or a confederate child. Interestingly, mothers of children with ADHD reported more positive parenting in response to prosocial behavior while attributing this behavior to less controllable and global/stable factors than comparison mothers; compliance also was seen as less controllable, global/stable, and intentional by mothers of children with ADHD.

Affect↗

PubMed2002

A molecular, morphometric and mechanical comparison of the structural elements of byssus from Mytilus edulis and Mytilus galloprovincialis.

Marine mussels are renowned for their ability to produce an extra-organismic tendon-like structure that can withstand the wave forces associated with the intertidal habitat. Initial characterization of byssal properties has focused on Mytilus edulis, with few detailed comparisons with other mussels. M. galloprovincialis, a closely related species, provides an opportunity for a thorough comparison. Three full-length cDNA clones encoding the byssal collagens, precollagen D (preCol-D), preCol-NG and preCol-P, were isolated from M. galloprovincialis. Comparisons with M. edulis preCol-D, preCol-NG and preCol-P reveal a 91.3 %, 88.6 % and 90.1 % identity with the cDNA and an 89.0 %, 88.1 % and 89.0 % identity with the deduced protein sequences, respectively. Key elements are maintained between the species: in particular, modeled bends in the collagen helix due to breaks in the Gly-X-Y pattern and the location of cysteine and putative 3,4-dihydroxyphenylalanine (DOPA) residues. A potentially important difference between the two is that, in all cases, M. galloprovincialis byssal collagens contain additional histidine residues in their flanking domains. The significance of this may lie in the ability of M. galloprovincialis to utilize more metal chelate cross-links, which have been implicated in byssal thread stability. M. edulis threads are typically twice the length and diameter of M. galloprovincialis threads and appear to contain nearly 10 % more collagen. These differences are maintained even when the different thread portions are compared. Despite differences in a number of parameters, most notably that whole M. galloprovincialis threads are stiffer, threads whether whole or separated into proximal and distal portions, have similar mechanical behaviors. It is apparent from this comparison that M. galloprovincialis and M. edulis are seemingly interchangeable models for byssal research.

Adaptation, Physiological↗

PubMed2006

How to use difference plots in quantitative method comparison studies.

Quantitative method comparison studies are fundamental to clinical biochemistry. The interpretation of quantitative method comparison studies relied heavily on correlation and regression methods until Bland and Altman first described the concept of absolute difference plots. Since then, many clinical biochemistry journals advocate the use of difference plots; however, there is a lot of ignorance about the validity as well as the pros and cons of the various difference plots. The most important issue in quantitative method comparisons studies is to determine limits of agreement that are valid across the whole range of values in the study so that correct data interpretation and conclusions occur. This article discusses validity as well as the pros and cons of difference plots and provides means to determine limits of agreement that are valid across the whole range of values in method comparison studies. Accordingly, correct data interpretation will be more likely and better conclusions should be arrived as a result.

Biomedical Research↗

PubMed1978

Testing for food allergy: a statistical comparison of cytotoxic and intracutaneous tests.

This study presents a comparison of in vitro cytotoxic food allergy test results with those of in vivo intracutaneous food allergy testing by both objective serial dilution titration and subjective provocation. During the study the cytotoxic test was utilized as a screening device for follow-up Lee intracutaneous testing, the latter providing statistics for both noted in vivo intracutaneous tests. The study is presented in two stages. The first stage documents almost 6000 comparison test results on 300 consecutive food-allergic otolarynogology patients. Thirty-four of the more frequently offending foods were utilized. Of the cytotoxic tests, 86% resulted in positive reactions. Of the positive cytotoxic reactors, 74% were intracutaneously re-checked. Only those negative cytotoxic reactors suspected of false negativity were so challenged, affording comparison statistics for a smaller 21% of the negative reactors. Poor correlation statistics for this select negative reacting group prompted a follow-up 30-patient study on 11 foods that appeared to possess a lesser potential for hypersensitivity production. The second stage emphasizes similar test comparisons on the negative cytotoxic reactors. The study concludes that no correlation exists between in vitro cytotoxic test determinations and those of in vivo intracutaneous testing by objective serial dilution titration or subjective provocation. Because most allergic individuals have multiple food allergies, clinical success utilizing the information obtained from any or all of these procedures may rely significantly on the tests' inherent tendency to identify multiple guilty foods for ultimate treatment.

Cytotoxicity Tests, Immunologic↗

PubMed2001

Quantification and facilitated comparison of von Willebrand factor multimer patterns by densitometry.

The analysis of von Willebrand factor (vWF) multimers is an important laboratory tool for distinguishing among the numerous subtypes of von Willebrand disease (vWD). Comparability and reproducibility of this method are insufficient; standardization and external references are pending. Interlaboratory comparison of results therefore may be difficult. We applied densitometry to obtain a reproducible quantification of vWF multimer patterns in healthy donors, patients with vWD variants, and factor VIII/vWF concentrates to improve the reproducibility and comparability of vWF multimer analysis. Multimers were separated and visualized luminographically on x-ray films. Films were scanned and evaluated by densitometry. The variation inherent in vWF multimer analysis and the range of the normal could be quantified. In vWD variants and factor VIII/vWF concentrates, densitometry could quantify and visualize alterations of vWF multimer patterns and facilitate their comparison. Densitometry permits a precise quantitative comparison of sample patterns to a reference plasma. It could be a valuable tool offering reproducible quantification and additional visualization of normal and pathologic vWF multimer patterns, facilitating their comparison and contributing to a standardization of vWF multimer analysis.

Adult↗

PubMed2005

Comparison of morning and afternoon exercise training for asthmatic children.

Fitness improvement was used to compare morning with afternoon exercise periods for asthmatic children. Children with persistent moderate asthma (according to GINA criteria), 8 to 11 years old, were divided into 3 groups: morning training group (N = 23), afternoon training group (N = 23), and non-training group (N = 23). The program was based on twice a week 90-min sessions for 4 months. We measured the 9-min running distance, resting heart rate and abdominal muscle strength (sit-up number) before and after the training. All children took budesonide, 400 microg/day, and an on demand inhaled ss-agonist. The distance covered in 9 min increased (mean +/- SEM) from 1344 +/- 30 m by 248 +/- 30 m for the morning group, from 1327 +/- 30 m by 162 +/- 20 m for the afternoon group, and from 1310 +/- 20 m by 2 +/- 20 m for the control group (P < 0.05 for the comparison of morning and afternoon groups with the control group by ANOVA and P > 0.05 for morning with afternoon comparison). The reduction of resting heart rate from 83 +/- 1, 85 +/- 2 and 86 +/- 1 bpm was 5.1 +/- 0.8 bpm in the morning group, 4.4 +/- 0.8 bpm in the afternoon group, and -0.2 +/- 0.7 bpm in the control group (P > 0.05 for morning with afternoon comparison and P < 0.05 versus control). The number of sit-ups in the morning, afternoon and control groups increased from 22.0 +/- 1.7, 24.3 +/- 1.4 and 23 +/- 1.1 sit-ups by 9.8 +/- 0.9, 7.7 +/- 1.4, and 1.9 +/- 0.7 sit-ups, respectively (P > 0.05 for morning with afternoon comparison and P < 0.05 versus control). No statistically significant differences were detected between the morning and afternoon groups in terms of physical training of asthmatic children.

Abdominal Muscles↗

PubMed2000

Comparison of two bioassay methods for determining deltamethrin resistance in German cockroaches (Blattodea: Blattellidae).

Susceptibility to deltamethrin of 10 strains of the German cockroach, Blattella germanica (L.), trapped in hotel kitchens in Singapore was determined. Two resistance detection bioassay methods (topical application and World Health Organization glass jar method) were compared. Resistance ratios based on 50% knockdown, obtained by comparison with the S strain, ranged from 17.7 to 4,235 for topical application and from 2.2 to 22 for the glass jar method. A field strain, with consistently low resistance ratios (topical method = 17.7, glass jar method = 2.2), was identified as a potential field strain to be used as a baseline for comparison with other field strains. Resistance ratios for the other field strains obtained by comparison with the R5 strain ranged from 24.5 to 239 for topical application and from 1.2 to 9.8 for the glass jar method. The results of our study demonstrate that deltamethrin-resistant German cockroaches are numerous in Singapore. Comparison between the two bioassay methods showed that there was significant correlation between KD50 and KT50 values. The glass jar method is similar to field situations but topical application is sensitive enough to define the magnitude of resistance. Differences between the two detection bioassays and the factors governing the choice of bioassay in monitoring resistance in German cockroaches are discussed.

Administration, Topical↗

PubMed1966

A comparison of two psychophysical methods using animals.

A discrimination box containing two levers with a light above each was used to train eight rats to press beneath the brighter light for a milk reinforcer. The brighter light was held constant and the comparison light was varied to produce 12 brightness differences. The animals were run under two experimental methods: the block method in which each brightness level comparison was presented for a block of 11 contiguous trials, and the staircase method in which the sequence of brightness comparisons was determined by the correctness of the response on the preceding comparison. The block method produced a smaller differential brightness threshold and a larger change in discrimination performance for stimulus magnitude changes than did the staircase method.

Animals↗

PubMed1969

Generalization during acquisition, extinction, and transfer of matching with an adjustable comparison.

Three groups of pigeons were given conditional discrimination training in which the number of standard stimuli was varied across groups. In the presence of each standard, a pigeon adjusted the comparison stimulus on a second key until the two keys matched. A report of this match (response on the first key) was reinforced. Transfer of the matching performance was investigated by adding new standards to the ones already available. All pigeons were exposed to two extinction sessions after 155 sessions of training. Rapidity of acquisition was inversely related to the number of standards presented. Generalization gradients derived from the several comparison stimuli showed that all pigeons reached a high level of accuracy in the presence of at least one standard, and some pigeons did so in the presence of as many as four of the six standards. There was no evidence of a systematic effect of extinction upon overall accuracy, or the individual generalization gradients. When a new standard was added, a given pigeon's performance (in terms of responding to the comparisons) was similar to performance in the presence of one of the old standards. However, the pigeons did not show evidence of confusion among the comparisons.

Journal Article↗

PubMed1993

Methodological aspects of international drug price comparisons.

Drug prices have become an important issue in the last few years as concerns about constrained healthcare resources have increased. Healthcare authorities in all industrialised countries are questioning whether their country is carrying a heavier burden than others in paying for drugs. In view of this discussion, several price comparison studies have been conducted. However, there is no generally accepted methodology on how to conduct price comparisons, and many methodological issues remain unresolved. The results of most published studies are affected by moderately serious methodological flaws, which are never properly addressed. The purpose of this study is to discuss the methodological issue of international drug price comparison, in terms of 6 points that appear to this author to be necessary to conduct a methodologically sound study. A previous review of a large number of drug price comparisons revealed that they all fail to take into account some or all of these 6 basic methodological points. Studies that fulfil the methodological criteria outlined in this paper are therefore urgently needed before drug pricing studies can be fully utilised as a basis for important policy decisions in the healthcare arena.

Drug Costs↗