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991.
Aim : The study was designed to determine the effect of computerized nutrition information on consumer food choice in two workplace restaurants, one in which customers had to pay for their lunch and the other providing a free lunch. Methods : Customers entering the restaurants were asked to make selections from the menu on a computer screen. The energy, saturated fatty acids, non-milk extrinsic sugars and non-starch polysaccharide content of the meal selected was displayed graphically in proportion to the dietary reference values. They were given the opportunity to change their selected meal and the composition of all meals was recorded. Results : The nutritional composition of the first meal provoked 16% of customers to make a second selection. The proportion of energy in the first selection had been 31% higher for saturated fatty acids and 23% higher for non-milk extrinsic sugars than the first selection made by people who were satisfied with their first choice. In their second attempt they succeeded in reducing both nutrients to levels similar to those present in the meals selected by people who had been satisfied with their first selection. Customers>> selections for non-starch polysaccharide and energy did not differ between the groups. The main changes made by customers to achieve improved second choices were to omit dishes (44%), add dishes (19%), make changes within a menu category (46%), and make changes from one menu category to another (26%). Conclusion : It was concluded that provision of graphical nutrition information on a computer screen could be used by a subset of the users of both restaurants to enable them to improve their menu selections to a similar composition to that selected by the other people who used the computer system. 相似文献
992.
993.
A clinical trial on the prevention of catheter-related sepsis using a new hub model. 总被引:8,自引:0,他引:8 下载免费PDF全文
M Segura F Alvarez-Lerma J M Tellado J Jiménez-Ferreres L Oms J Rello T Baró R Sánchez A Morera D Mariscal J Marrugat A Sitges-Serra 《Annals of surgery》1996,223(4):363-369
BACKGROUND: Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. METHODS: Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. RESULTS: Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03). CONCLUSIONS: A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks. 相似文献
994.
A RELIABLE MARKER OF ENDOTHELIAL CELL DYSFUNCTION: DOES IT EXIST? 总被引:19,自引:0,他引:19
995.
996.
Kevin L. Greason M.D. Jose A. Acosta M.D. Thomas J. Magrino M.D. Moogil Choe M.D. 《Diseases of the colon and rectum》1996,39(6):702-704
PURPOSE: This study was undertaken to clarify the importance of bleeding vascular ectasia of the colon as the etiology of massive lower gastrointestinal hemorrhage in patients 40 years of age or younger. METHODS: An otherwise healthy 21-year-old male was admitted to a tertiary medical center with massive lower gastrointestinal hemorrhage. Technetium-labeled red blood cell scan, selective visceral angiography, and colonoscopy identified the source of bleeding as vascular abnormality of the descending colon. Segmental colonic resection was performed. RESULTS: Histologic review of the specimen demonstrated a vascular ectasia. The patient recovered uneventfully and has had no further stigmata of hemorrhage. A review of the literature was undertaken to make clear the significance of vascular ectasia as the source for massive colonic hemorrhage in the young adult. CONCLUSION: This is the first report that documents histologically a vascular ectasia as the source of massive lower gastrointestinal hemorrhage in an otherwise healthy patient less than 40 years of age. Vascular ectasia is an uncommon cause of lower gastrointestinal hemorrhage in the young adult.The Chief, Bureau of Medicine and Surgery, Navy Department, Washington, DC, Clinical Investigation Program sponsored this report #84-16-1968-532, as required by HSETCINST 6000.41A. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of Defense, or the United States Government. 相似文献
997.
OBJECTIVE: To determine the most frequent clinical causes of a prolonged activated partial thromboplastin time (APTT) result, and to determine whether a new heparin-removal device (the Hepchek, Pall Biomedical, Glen Cove, NY 11542) is capable of efficiently detecting the causes of these values. DESIGN: A combination of chart review and laboratory testing comparing the criterion standard--the heparin chromogenic substrate assay--with the Hepchek. Laboratory investigations were blinded and controlled. SETTING: Inpatient, acute-care hospital. PATIENTS: A total of 1,000 hospital patients with a variety of hemostatic disorders. MAIN OUTCOME MEASURE: The extent to which the Hepchek accurately identified the etiology of a prolonged APTT result. RESULTS: The APTT was prolonged in 25.2% of samples. The presence of heparin in the sample was confirmed by chromogenic assay or by using the Hepchek heparin-removal filter. The presence of heparin was confirmed in 12.8% of all samples and in more than 50% of all abnormal samples. The cause of the abnormal APTT was often unappreciated by the clinician. Bayesian analysis of the Hepchek's ability to diagnose heparin correctly as the cause of the abnormal APTT showed a sensitivity of 100% and specificity of 99.9%. CONCLUSION: Use of the Hepchek in the routine clinical laboratory is an efficient and rapid method of detecting heparin as a cause of isolated prolonged APTT results, and should reduce demands for unwarranted coagulation analyses and inappropriate treatment with blood products. 相似文献
998.
R. B. Stewart 《Journal of clinical pharmacy and therapeutics》1993,18(4):243-253
Depression continues to be a major cause of morbidity and mortality in the elderly. It is estimated that 1–5% of elderly persons who live in the community and 5–43% of nursing–home patients have major depression. Symptoms of depression in the elderly do not differ substantially from younger patients. Tricyclic antidepressants continue to be the drugs of choice in the elderly because of their long record of use with proven efficacy, known adverse effect profile and availability of less expensive generic formulations. The newer secondgeneration antidepressants, including serotonin reuptake inhibitors, appear to offer a major advantage of fewer serious adverse effects in the elderly. This review will highlight recent developments regarding the prevalence and treatment of depression in the elderly. 相似文献
999.
Replication of Marburg virus in human endothelial cells. A possible mechanism for the development of viral hemorrhagic disease. 总被引:9,自引:0,他引:9 下载免费PDF全文
H J Schnittler F Mahner D Drenckhahn H D Klenk H Feldmann 《The Journal of clinical investigation》1993,91(4):1301-1309
Marburg and Ebola virus, members of the family Filoviridae, cause a severe hemorrhagic disease in humans and primates. The disease is characterized as a pantropic virus infection often resulting in a fulminating shock associated with hemorrhage, and death. All known histological and pathophysiological parameters of the disease are not sufficient to explain the devastating symptoms. Previous studies suggested a nonspecific destruction of the endothelium as a possible mechanism. Concerning the important regulatory functions of the endothelium (blood pressure, anti-thrombogenicity, homeostasis), we examined Marburg virus replication in primary cultures of human endothelial cells and organ cultures of human umbilical cord veins. We show here that Marburg virus replicates in endothelial cells almost as well as in monkey kidney cells commonly used for virus propagation. Our data support the concept that the destruction of endothelial cells resulting from Marburg virus replication is a possible mechanism responsible for the hemorrhagic disease and the shock syndrome typical of this infection. 相似文献
1000.
To improve the appropriateness and efficiency of diagnostic serological tests and subsequent antibiotic treatment, clinical data from 102 patients with unclassified arthritis were analysed to investigate whether the presence of positive IgG antibodies to Borrelia burgdorferi could be predicted. The clinical data were blindly ranked from 1 to 4 (1, Lyme arthritis unlikely; 4, Lyme arthritis very likely). Antibodies to B burgdorferi were positive in nine of 102 patients (9%). Six of 15 (40%) patients with rank numbers 3 and 4 were positive for antibodies to B burgdorferi, in contrast with only three of 87 (3%) patients with rank numbers 1 and 2. The likelihood ratio of positive Lyme serology for patients ranked 3 and 4 was 12.0, for patients ranked 2 to 4, 4.5, and for patients with arthritis of the knee, 3.0. These likelihood ratios were associated with a post-test probability of 55, 30, and 20% respectively. The clinical history in patients with unclassified arthritis can largely predict the presence of antibodies to B burgdorferi. The absolute value of a likelihood ratio can be a contributing factor in deciding to request tests for antibodies to B burgdorferi in patients with unclassified arthritis. 相似文献