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101.
Els Goetghebeur Saskia le Cessie Bianca De Stavola Erica EM Moodie Ingeborg Waernbaum “on behalf of” the topic group Causal Inference of the STRATOS initiative 《Statistics in medicine》2020,39(30):4922-4948
Although review papers on causal inference methods are now available, there is a lack of introductory overviews on what they can render and on the guiding criteria for choosing one particular method. This tutorial gives an overview in situations where an exposure of interest is set at a chosen baseline (“point exposure”) and the target outcome arises at a later time point. We first phrase relevant causal questions and make a case for being specific about the possible exposure levels involved and the populations for which the question is relevant. Using the potential outcomes framework, we describe principled definitions of causal effects and of estimation approaches classified according to whether they invoke the no unmeasured confounding assumption (including outcome regression and propensity score-based methods) or an instrumental variable with added assumptions. We mainly focus on continuous outcomes and causal average treatment effects. We discuss interpretation, challenges, and potential pitfalls and illustrate application using a “simulation learner,” that mimics the effect of various breastfeeding interventions on a child's later development. This involves a typical simulation component with generated exposure, covariate, and outcome data inspired by a randomized intervention study. The simulation learner further generates various (linked) exposure types with a set of possible values per observation unit, from which observed as well as potential outcome data are generated. It thus provides true values of several causal effects. R code for data generation and analysis is available on www.ofcaus.org , where SAS and Stata code for analysis is also provided. 相似文献
102.
103.
BACKGROUND AND PURPOSE
Conditioned gaping reactions reflect nausea-induced behaviour in rats. Cannabinoid 1 receptor (CB1) agonists interfere with the establishment of nausea-induced conditioned gaping; however, it is not known if their effects are mediated by an action at peripheral or central CB1 receptors.EXPERIMENTAL APPROACH
We utilized the conditioned gaping model of nausea to evaluate the effect of peripheral and central administration of the peripherally restricted CB1 agonist, CB13, on the establishment of LiCl-induced gaping in rats. We further evaluated the ability of HU-210 administered to the gustatory insular cortex (GIC) or visceral insular cortex (VIC) to interfere with LiCl-induced conditioned gaping and determined if this effect was mediated by CB1 receptors.KEY RESULTS
Central, but not peripheral, CB13 suppressed LiCl-induced conditioned gaping. Central administration of the potent CB1 agonist, HU-210, delivered to the VIC, but not the GIC, suppressed the establishment of LiCl-induced gaping reactions, but not LiCl-induced suppression of hedonic reactions or conditioned taste avoidance. This pattern of results suggests that HU-210 delivered to the VIC prevented LiCl-induced nausea, but not learning per se. The suppression of LiCl-induced conditioned gaping by HU-210 was mediated by CB1 receptors because it was prevented by co-administration of CB1 antagonist/inverse agonist, AM-251, into the VIC. A high dose of AM-251 (20 µg) administered alone into the VIC did not produce conditioned gaping reactions.CONCLUSIONS AND IMPLICATIONS
The nausea-relieving effects of CB1 agonists, but not the nausea-inducing effects of CB1 inverse agonists, are mediated, at least in part, by their action at the VIC in rats. 相似文献104.
GTA Jombo EM Mbaawuaga AN Gyuse MNO Enenebeaku EE Okwori EJ Peters S Akpan F Odey EA Etukumana JT Akosu 《Asian Pacific journal of tropical medicine》2010,3(5):402-406
ObjectiveTo ascertain the socio-cultural factors influencing the rate of utilization of insecticide treated bed nets (ITNs) in a malaria endemic city of Makurdi, north central Nigeria.MethodsThe study was cross-sectional in nature using systematic sampling method to identify households. Both quantitative and qualitative data was generated from adult women using structured and semi structured questionnaires, and focused group discussions (FGDs) to obtain information on rate and patterns of utilization of ITNs. Information such as age, educational level, marital status, awareness or otherwise of the existence of malaria, and factors influencing rate of ownership and utilization of ITNs were obtained. FGDs were used to obtain qualitative information on rate of utilization of ITNs not captured in the questionnaires. Data obtained was analysed using Epi Info 6 statistical software.ResultsAmong the respondents interviewed, 97.0% (2 013/2 075) were aware of existence of malaria and 87.0% of these (1 751/2 013) would associate it with mosquitoes. The rate of ownership of any bed net, ITNs and untreated bed nets (UTNs) was 25.1%, 17.0% and 8.3%, respectively. Utilization of ITNs among children was 30.0% (112/373) and UTNs 12.9% (48/373). Positive contributors to ITNs utilization were literacy, enhanced economy, experience of marriage, and being gainfully employed (P<0.05); while negative contributors were ignorance, poverty and some cultural beliefs and values.ConclusionsA more synchronized advocacy should be carried out on the potential benefits of ITNs utilization and sustained. Also ITNs should be made available to the people of the community at minimal or no cost. 相似文献
105.
Adam EM Eltorai Jack Haglin Sudheesha Perera Bielinsky A Brea Roy Ruttiman Dioscaris R Garcia Christopher T Born Alan H Daniels 《World journal of orthopedics》2016,7(6):361-369
Infections can hinder orthopedic implant function and retention.Current implant-based antimicrobial strategies largely utilize coating-based approaches in order to reduce biofilm formation and bacterial adhesion.Several emerging antimicrobial technologies that integrate a multidisciplinary combination of drug delivery systems,material science,immunology,and polymer chemistry are in development and early clinical use.This review outlines orthopedic implant antimicrobial technology,its current applications and supporting evidence,and clinically promising future directions. 相似文献
106.
The aim of this study was to evaluate the effect of hormone replacement therapy (HRT) on the expression of Ki-67, bcl-2 and c-erb.B2 in endometrial polyps during menopause. Sixteen patients using HRT and 24 untreated controls with endometrial polyps were enrolled in this study. Polypectomy was carried out by hysteroscopy. The presence of c-erb.B2, bcl-2 and Ki-67 expression was determined by immunohistochemistry. HRT was found to decrease Ki-67 and bcl-2 expression in endometrial polyps without affecting the c-erb.B2 staining reaction. HRT may cause endometrial polyp involution by decreasing proliferation and stimulating apoptosis. 相似文献
107.
Sara Gray MD FRCPC MPH Bjug Borgundvaag MD PhD CCFP‐EM Anita Sirvastava MD CCFP MSc Ian Randall MD Meldon Kahan MD MHSc CCFP FRCPC FCFP 《Academic emergency medicine》2010,17(10):1048-1054
Background: Use of a symptom‐triggered scale to measure the severity of alcohol withdrawal could reduce the rate of seizures and other complications. The current standard scale, the Clinical Institute of Withdrawal Assessment (CIWA), takes a mean (±SD) of 5 minutes to complete, requiring 30 minutes of nursing time per patient when multiple measures are required. Objectives: The objective was to assess the feasibility and reliability of a brief scale of alcohol withdrawal severity. Methods: The SHOT is a brief scale designed to assess alcohol withdrawal in the emergency department (ED). It includes four items: sweating, hallucinations, orientation, and tremor (SHOT). It was developed based on a literature review and a consensus process by emergency and addiction physicians. The SHOT was first piloted in one ED, and then a prospective observational study was conducted at a different ED to measure its feasibility and reliability. Subjects included patients who were in alcohol withdrawal. One nurse administered the SHOT and CIWA, and the physician repeated the SHOT independently. The SHOT was done only at baseline, before treatment was administered. Results: In the pilot study (12 patients), the SHOT took 1 minute to complete on average, and the CIWA took 5 minutes. Sixty‐one patients participated in the prospective study. For the SHOT and the CIWA done by the same nurse, the kappa was 0.88 (95% confidence interval [CI] = 0.52 to 1.0; p < 0.0001), and the Pearson’s r was 0.71 (p < 0.001). The kappa for the nurse’s CIWA score and the physician’s SHOT score was 0.61 (95% CI = 0.25 to 0.97; p < 0.0006), and the Pearson’s r was 0.48 (p = 0.002). The SHOTs performed by the nurse and physician agreed on the need for benzodiazepine treatment in 30 of 37 cases (82% agreement, kappa = 0.35, 95% CI = 0.03 to 0.67; p < 0.02). The mean (±SD) time taken by nurses and physicians to complete the SHOT was 1 (± 0.52) minute (median = 0.6 minutes). Seventeen percent of patients scored positive on the SHOT for hallucinations or disorientation. Conclusions: The SHOT has potential as a feasible and acceptable tool for measuring pretreatment alcohol withdrawal severity in the ED. Further research is needed to validate the SHOT, to assess the utility of serial measurements of the SHOT, and to demonstrate that its use reduces length of stay and improves clinical outcomes. ACADEMIC EMERGENCY MEDICINE 2010; 17:1048–1054 © 2010 by the Society for Academic Emergency Medicine 相似文献
108.
Intravenous gammaglobulin treatment of chronic idiopathic thrombocytopenic purpura 总被引:11,自引:0,他引:11
Bussel JB; Kimberly RP; Inman RD; Schulman I; Cunningham-Rundles C; Cheung N; Smithwick EM; O'Malley J; Barandun S; Hilgartner MW 《Blood》1983,62(2):480-486
High-dose intravenous gammaglobulin (IVIgG) was given to 12 children and adults with chronic idiopathic thrombocytopenic purpura (ITP) to avoid splenectomy or because they either failed to respond to or required maintenance with high doses of steroids and/or immunosuppressives. The average platelet count increase to initial therapy was 239,500/microliters (range 23,000-790,000). A concomitant IgG Fc receptor blockade, measured by IgG-sensitized 51Cr-labeled autologous erythrocytes, was seen in 11 of 11 patients tested, both splenectomized and not splenectomized, lasting 3-4 wk. Six or more months after treatment, 2 children are in remission, 2 children and 2 adults are stable requiring no therapy with platelet counts of approximately 50,000 and 30,000, respectively, 3 children require maintenance IVIgG therapy at 2-10-wk intervals, and 1 child and 2 adults have become refractory to further IVIgG. Splenectomy was not performed in 4 children. Two adults were able to discontinue daily prednisone. The 3 patients who became unresponsive to Swiss Red Cross gamma-globulin (IgSRK) therapy did so in conjunction with a markedly elevated platelet-associated IgG and IgM. Serum IgM increased an average of 103 mg/dl after the IVIgG infusions. No significant side effects were seen. 相似文献
109.
MA Nasar FRCP FRCP EM Lyle BSc MRPharmS 《International journal of clinical practice》1994,48(1):19-21
SUMMARY Serum potassium was measured within 24 hours in 156 patients (48 male, 108 female) with an average age of 81.9 years admitted to the unit with acute illness. Of the 156 patients, 88 (56.4%) were taking diuretics (none was on ACE inhibitors); 20 patients (12.8%) were also on digoxin therapy. In all, 24 patients (16%) had hypokalaemia and 3 (2%) hyperkalaemia. Hypokalaemia was seen in patients associated with acute illness. There was no significant difference between the diuretic and non-diuretic groups. Monitoring of serum potassium is not routinely indicated to detect hypokalaemia in patients on diuretic therapy except in those with severe hepatic or renal impairment or those on digoxin. 相似文献
110.