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Charlie Breitrose 《Computer Fraud & Security》1997,1997(8):8-10
Security conscious businesses in today's networked world not only look for new, improved ways to safeguard highly sensitive information, but also ways to detect or prevent intrusions, or theft of personal and company bank or credit cards, which can lead to sometimes catastrophic financial losses. Most computers and automatic teller machines still rely on personal identification numbers or passwords, things that can be stolen by a clever criminal. 相似文献
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BACKGROUND: The correct placement of large-bore venous catheters plays an important role in the management of haemodialysis patients. Whilst the procedure for landmark-based placement of these catheters is well known, the technique is not without significant morbidity and mortality. Complications include arterial puncture, haematoma, and pneumothorax. The procedure may be further complicated in these patients by venous thrombosis and abnormal vein position from multiple previous attempts at venous access. METHODS: Data on the use of ultrasound guidance versus anatomical landmarks for the placement of internal jugular vein (n = 69) and femoral vein (n = 30) dialysis access was retrospectively analysed over a 13-month period. Data collected included age, sex, duration on dialysis, number of vein cannulation sets required, number of attempts for successful cannulation, salvage of failed cannulation using landmark-based technique by ultrasound guidance, and the complication rate. RESULTS: Internal jugular vein cannulation using ultrasound was ultimately successful in 96.7% compared to 82% in the landmark group. The vein was entered on the first attempt in 83.3% of patients with ultrasound compared to 35.9% of the landmark group (P < 0.0001). Seven patients in whom the landmark technique was unsuccessful had access placed under ultrasound guidance. There were fewer carotid artery punctures in the ultrasound group (7.7 versus 0%, P = n.s.). In the femoral vein group, the vein was entered on the first attempt in 85.7% of patients with ultrasound compared to 56.25% of the landmark group (P = n.s.). CONCLUSIONS: The use of ultrasound guidance is associated with fewer complications and is more likely to lead to cannulation of the vein at the first attempt in haemodialysis patients. 相似文献
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Borrelia burgdorferi was identified as the etiological agent of Lyme disease in 1982. This Gram-negative spirochete is classified in the order Spirochaetales and the family Spirochaetaceae. The pathogen is fastidious, microaerophilic, mesophilic and metabolises glucose through the Embden-Meyerhof pathway. A generation time of 11 to 12 h at 37 degrees C in Barbour-Stoenner-Kelly medium has been reported. Lyme disease, named after Lyme in Connecticut, is distributed globally. It is the most commonly reported vector-borne disease in the United States, where the incidence is highest in the eastern and midwestern states. Since establishment of national surveillance in 1982, there has been a nine-fold increase in the number of cases reported to the U.S. Centers for Disease Control. The deer tick of the genus Ixodes is the primary vector of Lyme borreliosis. The tick may become infected with B. burgdorferi, by feeding on an infected host, at any point in its 2-year life cycle which involves larval, nymphal and adult stages. The infection rate in deer ticks may be as high as 40% in endemic areas. The primary vertebrate reservoirs for Ixodes are the white-footed mouse (Peromyscus leucopus) and the white-tailed deer (Odocopileus virginianus). Dairy cattle and other food animals can be infected with B. burgdorferi and hence some raw foods of animal origin might be contaminated with the pathogen. Recent findings indicate that the pathogen may be transmitted orally to laboratory animals, without an arthropod vector. Thus, the possibility exists that Lyme disease can be a food infection. In humans, the symptoms of Lyme disease, which manifest themselves days to years after the onset of infection, may involve the skin, cardiac, nervous and/or muscular systems, and so misdiagnosis can occur. 相似文献
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J Marsden M Gossop D Stewart D Best M Farrell P Lehmann C Edwards J Strang 《Canadian Metallurgical Quarterly》1998,93(12):1857-1867
AIM: To develop a brief, multi-dimensional instrument for assessing treatment outcome for people with drug and/or alcohol problems. The Maudsley Addiction Profile (MAP) is the first instrument to be developed in the United Kingdom for this purpose. DESIGN: Field testing with quota-recruitment of problem drug users and problem alcohol users in treatment with researcher and clinician-administered test-retest interviews. SETTING: Two community and two inpatient services at the Bethlem Royal and Maudsley Hospital, London. PARTICIPANTS: Subjects (160 drug users and 80 alcohol users) interviewed by eight interviews (four researchers and four clinicians), each of whom interviewed 30 subjects on two occasions. MEASURES: Sixty items across substance use, health risk, physical/psychological health and personal/social functioning domains. FINDINGS: Average completion time of the MAP was 12 minutes. The questionnaire was acceptable to a majority of subjects and performed well with both researcher and clinician interviewers. Internal reliability and feasible concurrent validity assessments of the scales and items were highly satisfactory. Test-retest reliability was good, average intraclass correlation coefficients across eight substances were 0.94 and 0.81 across health risk, health problems, relationship conflict, employment and crime measures. CONCLUSIONS: The MAP can serve as a core research instrument with additional outcome measures added as required. The collection of a set of reliable quantitative measures of problems among drug and alcohol users by research or treatment personnel for outcome evaluation purposes need not be time-consuming. 相似文献
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One-day-old specific-pathogen-free White Leghorn chicks were inoculated orally with Salmonella enteritidis phage type 4 to study adhesion and invasion of the ceca by immunohistochemistry. Positive staining bacilli were associated with the epithelial surface and were present in the lumen of the cecal crypts. They were observed in the interstitial tissue and in the cytoplasm of macrophage-like cells in the lamina propria. A granulomatous nodule containing positive staining bacilli was present in the submucosa of the cecum of one bird at 14 d after inoculation. 相似文献