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991.
Suspected multiple sclerosis: MR imaging with a thin-section fast FLAIR pulse sequence 总被引:28,自引:0,他引:28
Hashemi RH; Bradley WG Jr; Chen DY; Jordan JE; Queralt JA; Cheng AE; Henrie JN 《Radiology》1995,196(2):505
992.
Rats were concurrently exposed to a sustained avoidance/escape (SAE) procedure and a procedure for assessing demand for food. In the sustained SAE procedure, signalled shock avoidance/escape trials were presented at varying intervals averaging five minutes. The shock could be avoided by pulling on a ceiling chain early in the trial, or escaped by pulling on the chain later in the trial. Demand curves for food were generated by requiring 1, 5, 10, 20, 40, 80, 160, and 320 lever presses for each food pellet on successive days. The demand curve procedure was introduced after either brief (3 or 5 days) or extended (21 or 23 days) exposure to SAE. Following brief exposure to SAE, SAE animals showed decreased food intake and less elasticity of demand relative to non-SAE controls. Following extended exposure to SAE, these effects were diminished or absent. 相似文献
993.
994.
995.
Combined aspirin and sulfinpyrazone in the prevention of recurrent hemodialysis vascular access thrombosis 总被引:1,自引:0,他引:1
We carried out a pilot study in 15 hemodialysis patients with recurrent vascular access thrombosis to examine whether the combination of low dose aspirin (85 mg once daily) and sulfinpyrazone (200 mg three times daily) is safe and effective in the prevention of vascular access thrombosis. Hemostatic measurements were performed prior to and after four weeks of starting the drug combination. Baseline values for fibrinopeptide A were elevated in all patients while those for platelet factor 4, fibrinogen, antithrombin III and protein C were generally within normal limits. A major reduction in the frequency of vascular access thrombosis from 0.114 per month to 0.04 per month was noted during combined drug treatment (p < 0.001). Although in vitro platelet aggregation to various stimuli was markedly suppressed and platelet thromboxane B2 formation was almost completely inhibited in patients on aspirin/sulfinpyrazone, this was not associated with a significant further prolongation of the bleeding time. A relatively high rate of complications, particularly mild gastrointestinal bleeding, was noted in patients on aspirin/sulfinpyrazone that could not be predicted on the basis of pre-treatment hemostatic test results. 相似文献
996.
997.
YOU Yuan Hai SONG Yan Yan YAN Xiao Mei WANG Hai Bin ZHANG Meng Han TAO Xiao Xia LI Lei Lei ZHANG Yu Xin JIANG Xi Hong ZHANG Bing Hua ZHOU Hao XIAO Di JN Lian Mei FENG Zi Jian LUO Feng Ji ZHANG Jian Zhong 《Biomedical and environmental sciences : BES》2013,26(11):877-885
Objective To investigate molecular characterization of streptococcus pyogenes isolates involved in an outbreak of scarlet fever in China in 2011. Methods Seventy-four 5treptococcol pyogenes involved in an outbreak of scarlet fever were isolated from pediatric patients in the areas with high incidence in China from May to August of 2011. Emm genotyping, pulsed-field gel electrophoresis (PFGE), superantigen (SAg) genes and antimicrobial susceptibility profiling were analyzed for these isolates. Results A total of 4 different emm types were identified. Emm12 was the most prevalent type which contained four predominating PFGE patterns corresponding to four different virulence and superantigen profiles. Emm12(79.7%) and emml (14.9%) accounted for approximately 94% of all the isolates. The speA gene was all negative in emm12 isolates and positive in emml isolates. All strains were resistant to erythromycin, and 89.4% of them were resistant to erythromycin, tracycline, and clindamycin simultaneously. Conclusion Several highly diversified clones with a high macrolide resistance rate comprise a predominant proportion of circulating strains, though no new emm type was found in this outbreak. The data provide a baseline for further surveillance of scarlet fever, which may contribute to the explanation of the outbreak and development of a GAS vaccine in China. 相似文献
998.
Y D Senturia L J Bauman Y M Coyle W Morgan D L Rosenstreich M D Roudier H Mitchell R Gruchalla E F Crain 《Ambulatory Pediatrics》2001,1(4):194-200
OBJECTIVE: To determine the accuracy of parent report and the accuracy of the medical record in documenting physician performance of elements of pediatric asthma care in the primary care setting. METHODS: A convenience sample of 79 English-speaking parents of 4--12-year old children with asthma presenting to medical center--affiliated inner-city primary care pediatric clinics in the Bronx, Dallas, and Chicago was enrolled, and the office visit was audiotaped. Parents were interviewed 1--16 days after the visit by telephone. OUTCOME MEASURES: Accuracy of parent report was the primary outcome. The "reference standard" was an independent evaluation of the audiotaped record of the primary care visit. The National Asthma Education and Prevention Program was used as a guide to select data elements to assess quality of pediatric asthma care during primary care visits. RESULTS: Sufficient documentation was significantly (P <.001) less likely to be present in the medical record than in the follow-up interview for each element of care. When these elements were combined into a cumulative score, 71% of parent interviews but only 37% of medical records scored > or = 5 (out of a possible 6), with 29% of medical records scoring < 3. Parents were able to accurately report (concordance of parent data with audiotape reference standard) whether or not the visit had included performance of 5 of the 6 elements of care. CONCLUSIONS: Our study suggests that parent telephone interview within 2 weeks after the visit is more accurate than the medical record for documentation of the quality of asthma care in pediatric primary care visits. The medical record was not sufficient to assess the quality of primary care related to asthma, primarily because of missing data. Therefore, our data suggest that assessing quality of care using the medical record will not only bias the findings in the direction of more deficient care but will also make improvement in care more difficult. Further validation of our strategy for using parent report to assess the quality of care in primary care visits will require its application in a variety of other primary care settings. 相似文献
999.
Jill M. Wecht Dwindally Rosado-Rivera Joseph P. Weir Adrian Ivan Christina Yen William A. Bauman 《Archives of physical medicine and rehabilitation》2013
Objectives
To determine the effect of an escalating dose of droxidopa (100, 200, and 400mg) compared with placebo on seated blood pressure (BP) in hypotensive individuals with spinal cord injury (SCI). Secondarily, we aimed to determine the effect of droxidopa on (1) supine BP and heart rate, (2) the change in BP and heart rate when these individuals were transferred from the supine to the seated position, and (3) adverse event (AE) reporting.Design
Open-label dose titration trial.Setting
A Veterans Administration Medical Center.Participants
Participants with SCI (C3-T12) (N=10) were studied during 4 laboratory visits. Subjects visited the laboratory for about 5 hours on each visit, which incorporated a 30-minute seated baseline, a 30- to 60-minute supine, and a 4-hour seated postdrug observation.Interventions
Placebo on visit 1, droxidopa 100mg on visit 2, droxidopa 200mg on visit 3, and droxidopa 400mg on visit 4.Main Outcome Measures
BP and heart rate changes from baseline to the postdrug period, orthostatic heart rate and BP responses, and subjective AE reporting.Results
Seated BP was significantly elevated with 400mg droxidopa compared with placebo and 100mg droxidopa for 3 hours and was elevated for 2 hours compared with 200mg droxidopa. Increase in supine BP was not worsened following droxidopa, and the expected fall in BP when transferred to the seated position was prevented with droxidopa 200 and 400mg. There were no significant differences in the heart rate response or AE reporting among the study visits.Conclusions
Our preliminary findings suggest that droxidopa, at the doses tested, does not cause excessive increases in supine BP and the 400-mg dose appears to be effective at increasing seated BP for up to 3 hours in persons with SCI. 相似文献1000.
J Chen A Bauman C Rissel K C Tang R Forero B Flaherty 《The Journal of adolescent health》2000,26(1):53-63
PURPOSE: To examine for the first time adolescent substance use by ethnicity, given the high proportion of migrants from non-English-speaking countries in New South Wales, (NSW), Australia. METHODS: Data from four surveys of NSW secondary school students in 1983, 1986, 1989, and 1992 were used for this analysis. The prevalence of substance use by whether English was spoken at home was stratified by sex and age using data from the most recent survey year. Adjusted odds ratios and 95% confidence intervals were produced by simultaneous logistic regression, adjusting for sex, age group, and the interaction term of sex and age for each of these substances, and for each survey year separately. Data from 1989 and 1992 were pooled together to examine rates of substance use by ethnic subgroups which reflect migration patterns. RESULTS: The prevalence of smoking and alcohol and illicit drug use was consistently lower among NSW adolescents speaking a language other than English at home, compared with those speaking English at home in all survey years. Only the prevalence of solvent sniffing was higher among younger adolescents speaking a language other than English at home. Students from Southeast Asia showed consistently lower rates of usage of all substances compared to all other groups. CONCLUSIONS: There may be different opportunities for the prevention of adolescent substance use among native English speakers to be gained from non-English-speaking cultures. 相似文献