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Evidence-Based Medicine and Psychiatric Practice   总被引:4,自引:0,他引:4  
Evidence-based medicine (EBM) has been defined as the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients. EBM requires the ability to apply a knowledge of medical informatics (e.g., efficiently searching the medical literature) and clinical epidemiology (e.g., being able to critically appraise the literature) to the treatment of individual patients. This article provides an introduction to the history, philosophy, and methods of EBM as applied to psychiatric practice. The article summarizes the five-step EBM model: (1) formulate the question; (2) search for answers; (3) appraise the evidence; (4) apply the results; and (5) assess the outcome. Resources (including Web sites) for further learning are provided.  相似文献   
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Bile leaks occur in up to 27 per cent of liver transplant patients after biliary reconstruction. Synthetic sealants have not been investigated for these biliary procedures. We performed a randomized controlled study to evaluate a novel absorbable polyethylene glycol/collagen biopolymer sealant (CT3 Surgical Sealant) after incomplete end-to-end choledochocholedochostomy (CDCD) in pigs. Pigs (n = 18) underwent transection of the common bile duct and incomplete CDCD over a T-tube, leaving a one-sixth circumferential defect anteriorly. Animals were randomly assigned to treatment (CDCD with sealant, n = 9) or control (no sealant, n = 9). Drains were used to monitor leak volume and bilirubin (bili) concentration. Cholangiography was performed on postoperative day 3. Leaks were defined as drain bili/serum bill > 3, total drain output > 10 mL/kg, and/or extravasation on cholangiography. Animals sacrificed at 3 and 8 weeks (n = 4 and n = 5 from each group, respectively) underwent pathologic examination of the CDCD site. Statistical methods included Student's t test, chi2, linear regression, and analysis of variance procedures. The control group had a higher drain output rate over the first 4 postoperative days than the treatment group (P < 0.05, analysis of variance). Five of nine (56%) control and one of nine (11%) treatment animals had a bile leak (P < 0.05, chi2). There was no major inflammatory response to the sealant versus controls. We conclude that CT3 is effective in decreasing biliary leaks in an incomplete CDCD porcine model with no major adverse pathologic changes. This sealant should be considered for trials for biliary reconstruction in humans.  相似文献   
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OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.  相似文献   
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Increased placental apoptosis in intrauterine growth restriction   总被引:2,自引:0,他引:2  
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n  = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401)  相似文献   
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