Search results for "Linear model"
showing 10 items of 598 documents
Bipedal distribution of human vestibular‐evoked postural responses during asymmetrical standing
2002
Galvanic vestibular stimulation (GVS) evokes responses in muscles of both legs when bilateral stimuli are applied during normal stance. We have used this technique to assess whether asymmetrical standing alters the distribution of responses in the two legs. Subjects stood either asymmetrically with 75% of their body weight on one leg or symmetrically with each leg taking 50% of their body weight. The net response in each leg was taken from changes in ground reaction force measured from separate force plates under each foot. The net force profile consisted of a small initial force change that peaked at approximately 200 ms followed by an oppositely directed larger component that peaked at ap…
Differences in cannabis-related experiences between patients with a first episode of psychosis and controls
2016
BackgroundMany studies have reported that cannabis use increases the risk of a first episode of psychosis (FEP). However, only a few studies have investigated the nature of cannabis-related experiences in FEP patients, and none has examined whether these experiences are similar in FEP and general populations. The aim of this study was to explore differences in self-reported cannabis experiences between FEP and non-psychotic populations.MethodA total of 252 subjects, who met International Classification of Diseases (ICD)-10 criteria for FEP, and 217 controls who reported cannabis use were selected from the Genetics and Psychosis (GAP) study. The Medical Research Council Social Schedule and t…
Cognitive impairment is related to oxidative stress and chemokine levels in first psychotic episodes.
2011
Abstract Introduction This study measures the levels of various markers of oxidative stress and inflammation in blood samples from first-episode psychosis (FEP) patients, and examines the association between these peripheral biomarkers and cognitive performance at 6 months after treatment. Methods Twenty-eight FEP patients and 28 healthy controls (matched by age, sex and educational level) had blood samples taken at admission for assessment of total antioxidant status, superoxide dismutase (SOD), total glutathione (GSH), catalase (CAT), glutathione peroxidase, lipid peroxidation, nitrites and the chemokine monocyte chemoattractant protein-1 (MCP-1). A battery of cognitive tests was also app…
Is there a group effect? It depends on how you ask the question: Intraclass correlations for California Psychotherapy Alliance Scale–Group items.
2014
California Psychotherapy Alliance Scale-Group (CALPAS-G) data were collected from 1,138 group sessions attended by 248 group members in 16 counseling groups. Hierarchical linear modeling (HLM) was used to derive between-groups, between-member, and between-session variance components and intraclass correlation coefficients (ICCs) for the 12 CALPAS-G items. Using Ledermann and Kenny's (2012) descriptions of variable types, we examined differences in between-groups variance for the 6 CALPAS-G items classified as "Individual" items and the 6 CALPAS-G items classified as "Group" items. A Related-Samples Wilcoxon's Signed Ranked Test showed that the ICCs for the Group items were significantly lar…
Baroreflex control of heart rate during sleep in severe obstructive sleep apnoea: effects of acute CPAP
2006
Baroreflex control of heart rate during sleep (baroreflex sensitivity; BRS) has been shown to be depressed in obstructive sleep apnoea (OSA), and improved after treatment with continuous positive airway pressure (CPAP). Whether CPAP also acutely affects BRS during sleep in uncomplicated severe OSA is still debatable. Blood pressure was monitored during nocturnal polysomnography in 18 patients at baseline and during first-time CPAP application. Spontaneous BRS was analysed by the sequence method, and estimated as the mean sequence slope. CPAP did not acutely affect mean blood pressure or heart rate but decreased cardiovascular variability during sleep. Mean BRS increased slightly during CPAP…
Detection of gamma-hydroxybutyrate in hair: Validation of GC–MS and LC–MS/MS methods and application to a real case
2012
A gas chromatography-mass spectrometry (GC-MS) and a liquid chromatography tandem mass spectrometry (LC-MS/MS) method were validated for quantifying endogenous and exogenous hair concentrations of gamma-hydroxybutyrate (GHB). The GC-MS method is based on overnight extraction of 25 mg hair in NaOH at 56 °C, liquid/liquid extraction in ethylacetate and trimethylsylil derivatization; analysis is by electron ionization and single ion monitoring of three ions. The LC-MS/MS method entails a rapid digestion of 25 mg hair with NaOH at 75 °C for 40 min, liquid/liquid extraction in ethylacetate and reconstitution of the extract in the LC mobile phase; negative ion electrospray ionization and multiple…
Prenatal and postnatal insecticide use and infant neuropsychological development in a multicenter birth cohort study
2013
There is little evidence about exposure to currently used insecticides during early life periods and adverse effects on child neuropsychological development. The aim of this study is to examine the association between residential insecticide use during pregnancy and infancy, and the development of children.Study subjects were participants in the INMA (Environment and Childhood) Project, a Spanish multicenter birth cohort study. Prenatal and postnatal use of indoor insecticides and other variables were obtained from personal interview during pregnancy and infancy. Mental and psychomotor development was assessed around 14 months using the Bayley Scales of Infant Development. The associations …
Therapy expectations and physical comorbidity affect quality of life in chronic hepatitis C virus infection.
2007
Summary. Hepatitis C virus (HCV) infection is associated with a significant reduction of health related quality of life (QOL), the causes and mechanisms of which are still unknown. To explore whether treatment history could affect QOL, we examined patients with detectable HCV viraemia who had a different therapeutic background. Two hundred sixty-four consecutive subjects with chronic HCV infection and detectable viraemia were enrolled. Of these, 163 were untreated patients, 43 were relapsers, 58 were nonresponders (NR) to nonpegylated interferon (IFN) therapy. To assess QOL, three self-report instruments were employed: the Short Form-36 (SF-36), the Chronic Liver Disease Questionnaire (CLD…
Stretch-reflex mechanical response to varying types of previous muscle activities
2002
This study was designed to examine the effects of varying types of background muscle activity on the stretch-reflex mechanical response. A rapid stretch was applied to the calf muscles after an isometric (pre-ISO), shortening (pre-SHO) and lengthening contraction (pre-LEN) with several pre-contraction levels, respectively. The stretch perturbation was applied with the tibio-tarsal joint angle at 90 degrees. The ankle joint torque elicited by the stretch showed a first peak (non-reflex torque: NRT), a transient drop and a second peak (reflex torque: RT). The muscle activities before the stretch clearly influenced the stretch-reflex mechanical response. The NRT reached the largest peak with t…
Studies on adaptation to complete dentures. Part II: Oral stereognosis and tactile sensibility
1995
High oral perception is thought to contribute to poor adaptation to new dentures. The aim of this study was to evaluate the oral stereognosis and tactile sensibility in edentate subjects and relate these to patient age and capability of adaptation to new prostheses. A total of 67 patients were provided with new complete dentures 2-3 weeks before the experiment. In 54 subjects, the oral stereognosis was evaluated by 12 different test-pieces, which were placed unseen on the tongue and had to be recognized. In 38 patients, the oral tactile sensibility was determined in the premolar area using copper foils. The capability of adaptation was evaluated by a questionnaire. Denture retention was ass…