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There are more than 200,000 Canadians living with permanent pacemakers or implantable defibrillators, many of whom will require surgery or invasive procedures each year. They face potential hazards when undergoing surgery; however, with appropriate planning and education of operating room personnel, adverse device-related outcomes should be rare. This joint position statement from the Canadian Cardiovascular Society (CCS) and the Canadian Anesthesiologists' Society (CAS) has been developed as an accessible reference for physicians and surgeons, providing an overview of the key issues for the preoperative, intraoperative, and postoperative care of these patients. The document summarizes the limited published literature in this field, but for most issues, relies heavily on the experience of the cardiologists and anesthesiologists who contributed to this work. This position statement outlines how to obtain information about an individual's type of pacemaker or implantable defibrillator and its programming. It also stresses the importance of determining if a patient is highly pacemaker-dependent and proposes a simple approach for nonelective evaluation of dependency. Although the document provides a comprehensive list of the intraoperative issues facing these patients, there is a focus on electromagnetic interference resulting from electrocautery and practical guidance is given regarding the characteristics of surgery, electrocautery, pacemakers, and defibrillators which are most likely to lead to interference. The document stresses the importance of preoperative consultation and planning to minimize complications. It reviews the relative merits of intraoperative magnet use vs reprogramming of devices and gives examples of situations where one or the other approach is preferable.  相似文献   
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Vibrio parahaemolyticus is the leading bacterial cause of food-borne illness due to the consumption of contaminated seafood. The aim of the present study was to determine the population of its subtypes and establish a better understanding of the various types of V. parahaemolyticus strains that are causing human illness in Canada. The subtypes for 100 human clinical isolates of V. parahaemolyticus collected between 2000 and 2009 were determined by performing serotyping, ribotyping, pulsed-field gel electrophoresis, and multilocus sequence typing. Within this panel of strains, there was a high level of diversity (between 22 and 53 subtypes per method), but the presence of predominant clones with congruent subtypes between the various methods was also observed. For example, all 32 isolates belonging to sequence type 36 (ST36) were from serogroup O4, while 31 of them were ribotype EcoVib235-287, and 24 of the 32 were SfiI pulsed-field gel electrophoresis (PFGE) pattern VPSF1.0001. With regard to the presence of known virulence genes, 74 of the 100 isolates were PCR positive for the presence of the thermostable direct hemolysin (tdh); and 59 of these 74 strains also contained the second virulence marker, the tdh-related hemolysin (trh). The detection of trh was more predominant (81%) among the clinical isolates, and only four (4%) of the clinical isolates tested negative for the presence of both tdh and trh. This database, comprising 100 clinical isolates of V. parahaemolyticus strains from Canada, forms a baseline understanding of subtype diversity for future source attribution and other epidemiologic studies.  相似文献   
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An outbreak of community-associated methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infection (SSTI) occurred in a college football team from August to September 2003. Eleven case-players were identified, and boils were the most common sign. Linemen had the highest attack rate (18%). Among 99 (93% of team) players with cultured specimens, 8 (8%) had positive MRSA nasal cultures. All available case-players' MRSA isolates characterized had the community-associated pulsed-field type USA300. A case-control study found that sharing bars of soap and having preexisting cuts or abrasions were associated with infection. A carrier-control study found that having a locker near a teammate with an SSTI, sharing towels, and living on campus were associated with nasal carriage. Successful outbreak control measures included daily hexachlorophene showers and hygiene education.  相似文献   
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Adventure travel is becoming more popular, increasing the likelihood of contact with unusual pathogens. We investigated an outbreak of leptospirosis in "Eco-Challenge" multisport race athletes to determine illness etiology and implement public health measures. Of 304 athletes, we contacted 189 (62%) from the United States and 26 other countries. Eighty (42%) athletes met our case definition. Twenty-nine (36%) case-patients were hospitalized; none died. Logistic regression showed swimming in the Segama River (relative risk [RR]=2.0; 95% confidence interval [CI]=1.3 to 3.1) to be an independent risk factor. Twenty-six (68%) of 38 case-patients tested positive for leptospiral antibodies. Taking doxycycline before or during the race was protective (RR=0.4, 95% CI=0.2 to 1.2) for the 20 athletes who reported using it. Increased adventure travel may lead to more frequent exposure to leptospires, and preexposure chemoprophylaxis for leptospirosis (200 mg oral doxycycline/week) may decrease illness risk. Efforts are needed to inform adventure travel participants of unique infections such as leptospirosis.  相似文献   
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Background  

Information on the effectiveness of elementary school level, tobacco-use prevention programs is generally limited. This study assessed the impact of a structured, one-time intervention that was designed to modify attitudes and knowledge about tobacco. Participants were fifth-grade students from schools in western New York State.  相似文献   
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BACKGROUND: A portable automated component collection system that produces double (2) units of leukoreduced RBCs (DRBCs) from a single donation was evaluated. This study analyzed quality of the collected and final products, the efficacy of automated leukoreduction, and donor safety. STUDY DESIGN AND METHODS: The system was used to collect 120 DRBCs. WBCs were removed from 90 products with machine-controlled filtration. DRBCs were collected in ACD-A and stored in AS-1 for 42 days at 1 to 6 degrees C. Pre- and postprocedure donor vital signs and hematologic parameters were measured. Procedure time, product characteristics, and adverse events were also recorded. In vitro studies were performed on all products on Day 0 and at end of storage. In vivo recoveries of 28 leukoreduced and 9 nonleukoreduced products were measured on Day 42. RESULTS: Day 0 mean percentage of hemolysis for leukoreduced and nonleukoreduced units was 0.05 percent. DRBCs had residual WBC counts of less than 1 x 106 cells per unit and mean RBC recovery after filtration of 91.9 +/- 2.7 percent. Mean 24-hour recovery after infusion for leukoreduced units at end of storage was 80.9 +/- 6.9 percent and nonleukoreduced units was 77.6 +/- 5.8 percent (p> 0.05). No clinically significant changes in donor vital signs or serious adverse events were observed. CONCLUSIONS: The quality of leukoreduced RBCs collected with this portable automated component collection system met or exceeded FDA requirements. This automated system is safe and effective for collection and processing of 2 units of RBCs suitable for transfusion.  相似文献   
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Kava Kava is an herbal supplement used as an alternative to antianxiety drugs. Although some reports suggest an association of Kava Kava with hepatotoxicity , it continues to be used in the United States due to lack of toxicity characterization. In these studies F344/N rats and B6C3F1 mice were administered Kava Kava extract orally by gavage in corn oil for two weeks, thirteen weeks or two years. Results from prechronic studies administered Kava Kava at 0.125 to 2 g/kg body weight revealed dose-related increases in liver weights and incidences of hepatocellular hypertrophy. In the chronic studies, there were dose-related increases in the incidences of hepatocellular hypertrophy in rats and mice administered Kava Kava for up to 1 g/kg body weight. This was accompanied by significant increases in incidences of centrilobular fatty change. There was no treatment- related increase in carcinogenic activity in the livers of male or female rats in the chronic studies. Male mice showed a significant dose-related increase in the incidence of hepatoblastomas. In female mice, there was a significant increase in the combined incidence of hepatocellular adenoma and carcinoma in the low and mid dose groups but not in the high dose group. These findings were accompanied by several nonneoplastic hepatic lesions.  相似文献   
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