Catalogue Search | MBRL
هل أنت متأكد أنك تريد إزالة الكتاب من الرف؟
{{itemTitle}}
8,958
نتائج ل
"Simpson, R. S"
صنف حسب:
Is Mental Health in the Canadian Population Changing over Time?
Objective:
Mental health in populations may be deteriorating, or it may be improving, but there is little direct evidence to support either possibility. Our objective was to examine secular trends in mental health indicators from national data sources.
Methods:
We used data (1994–2008) from the National Population Health Survey and from a series of cross-sectional studies (Canadian Community Health Survey) conducted in 2001, 2003, 2005, and 2007. We calculated population-weighted proportions and also generated sex-specifc, age-standardized estimates of major depressive episode prevalence, distress, professionally diagnosed mood disorders, antidepressant use, self-rated perceived mental health, and self-rated stress.
Results:
Major depression prevalence did not change over time. No changes in the frequency of severe distress were seen. However, there were increases in reported diagnoses of mood disorders and an increasing proportion of the population reported that they were taking antidepressants. The proportion of the population reporting that their life was extremely stressful decreased, but the proportion reporting poor mental health did not change.
Conclusions:
Measures based on assessment of symptoms showed no evidence of change over time. However, the frequency of diagnosis and treatment appears to be increasing and perceptions of extreme stress are decreasing. These changes probably reflect changes in diagnostic practice, mental health literacy, or willingness to report mental health concerns. However, no direct evidence of changing mental health status was found.
Journal Article
Epidural catheter tip cultures: Results of a 4-Year audit and implications for clinical practice
Background and Objectives: The aims of this study were to evaluate the clinical relevance of routine microbiological culture of epidural catheter tips after use in acute pain management, and to identify patterns of culture result with respect to both indications for, and duration of, epidural catheterization.
Methods: The Acute Pain Service (APS) reviews all patients under its care at least daily and keeps detailed records on each. Over a 4-year period, when APS protocol required epidural catheter tips to be sent for microbiological culture on removal, the APS saw 1,810 patients who had received epidural analgesia. The records of these patients were reviewed.
Results: Culture results were available for 1,443 (79.7%) patients: 1,027 catheter tips (71.2%) were sterile, while 416 (28.8%) were positive for at least 1 type of microorganism. Clinically, no epidural space infections were identified. The highest positive culture rates were found from epidural catheters used in the treatment of pain from fractured ribs or fractured pelves, while the lowest incidences occurred in elective orthopedic and thoracic surgery. The proportion of epidural catheters with positive culture results steadily increased with the duration of catheterization, but there were no clinically significant differences for catheters left in situ for either 3 or 4 days.
Conclusions: We concluded that a significant proportion of epidural catheter tips may be “culture positive” after removal. It is suggested that this probably represents colonization of the skin at the catheter insertion site and subsequent contamination of the catheter tip on removal of the catheter. The large number of “culture positive” tips in the absence of clinically identifiable epidural space infection suggests that routine culture of epidural catheter tips is clinically irrelevant in the vast majority of cases, and that it is not a good predictor of the presence of an epidural space infection.
Reg Anesth Pain Med 2000;25:360-367.
Journal Article
Menstrual Disorders and Occupational, Stress, and Racial Factors Among Military Personnel
Few studies have assessed multiple stress factors as a potential risk for menstrual disorders. This study evaluated whether work-related stress or life event stress was associated with alterations in menstrual function of military personnel. The study is unique in that it evaluated the association between race and three job factors—job stress, handling chemical mixtures, and being a military or civilian employee of the US Air Force. A comprehensive questionnaire was administered to 170 healthy, premenopausal employed women to examine the relationship between work-related or life event stress and menstrual disorders. Multiple logistic regression analyses showed no statistically significant association between work-related stress and menstrual disorders, whereas life event stress was significantly associated with dysmenorrhea (odds ratio [OR], 2,20; 95% confidence interval [CI], 1.08 to 4.50) abnormal cycle length (OR, 3.42; CI, 1.12 to 10.50), and hypermenarrhea (OR, 2.99; 95% CI, 1.20 to 7.42). Having one or more menstrual disorders was significantly associated with life events by race interaction (OR, 6.52; 95% CI, 2.45 to 17.36). Non-Caucasians had significantly increased risks of hypermenorrhea (OR, 4.99; 95% CI, 2.07 to 12.05) and abnormal cycle length (OR, 4.12; 95% CI, 1.47 to 11.55). The prevalence of menstrual disorders in this military population was 31.2% for dysmenorrhea, 17.9% for hypermenorrhea, and 12.0% for abnormal cycle length. This study suggests that women in the military report less day-to-day job stress but more atypical life events, including those related to their jobs, and that these life events are associated with adverse menstrual consequences.
Journal Article
Dynamic Model of a Current Transformer
The performance of current transformers and its errors during short-circuit conditions are very important with regard to protective devices in power networks. Core saturation of protective current transformers due to the d.c. component of fault current and the qualitative effect of core hysteresis resulting in residual flux are both well-known phenomena which can produce distorted output currents. A numerical technique for the mathematical representation of the flux density/field strength relationship, including the effects of hysteresis for a current transformer magnetic material, is presented, based on the use of exponential series. The simulation results are compared with experimental results obtained from a sample current transformer.
Journal Article
Weight Change and Lung Function: Implications for Workplace Surveillance Studies
This study evaluated the relationship between weight change and longitudinal measurement of lung function among 361 men providing at least five pulmonary function tests. The men in this study were participants in a workplace pulmonary surveillance program for subjects with exposure to refractory ceramic fibers (RCFs). Occupationa and environmental studies are generally designed to evaluate factors suspected of causing excess decline in lung function. Failure to adequately account for all significant factors may lead to erroneous conclusions regarding change in lung function. This study utilized two different statistical models to evaluate longitudinal changes in a cohort of RCF workers. What was unique to this study was the modeling of longitudinally measured initial weight, weight change, and longitudinal exposure before and during the period of observation. Results showed a strong relationship between weight gain and longitudinal loss in lung function that approximated forced vital capacity declines of 16 mL for every kilogram of weight gain per year in both models. This value is comparable or greater in magnitude and significance to other factors known to be inversely related to lung function, such as age and pack-years smoking to time of initial testing In conclusion, weight gain was found to have a significant impact on longitudinal change in lung function. Therefore, weight gain becomes a very important variable th requires consideration whenever longitudinal studies of pulmonary function are conducted.
Journal Article
Systemic gene expression in Arabidopsis during an incompatible interaction with Alternaria brassicicola
Pathogen challenge can trigger an integrated set of signal transduction pathways, which ultimately leads to a state of \"high alert,\" otherwise known as systemic or induced resistance in tissue remote to the initial infection. Although large-scale gene expression during systemic acquired resistance, which is induced by salicylic acid or necrotizing pathogens has been previously reported using a bacterial pathogen, the nature of systemic defense responses triggered by an incompatible necrotrophic fungal pathogen is not known. We examined transcriptional changes that occur during systemic defense responses in Arabidopsis plants inoculated with the incompatible fungal pathogen Alternaria brassicicola. Substantial changes (2.00-fold and statistically significant) were demonstrated in distal tissue of inoculated plants for 35 genes (25 up-regulated and 10 down-regulated), and expression of a selected subset of systemically expressed genes was confirmed using real-time quantitative polymerase chain reaction. Genes with altered expression in distal tissue included those with putative functions in cellular housekeeping, indicating that plants modify these vital processes to facilitate a coordinated response to pathogen attack. Transcriptional up-regulation of genes encoding enzymes functioning in the β-oxidation pathway of fatty acids was particularly interesting. Transcriptional up-regulation was also observed for genes involved in cell wall synthesis and modification and genes putatively involved in signal transduction. The results of this study, therefore, confirm the notion that distal tissue of a pathogen-challenged plant has a heightened preparedness for subsequent pathogen attacks.
Journal Article