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排序方式: 共有844条查询结果,搜索用时 15 毫秒
1.
Doing it right the first time: quality improvement and the contaminant blood culture. 总被引:5,自引:3,他引:2
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F I Weinbaum S Lavie M Danek D Sixsmith G F Heinrich S S Mills 《Journal of clinical microbiology》1997,35(3):563-565
The aim of the project was to determine whether the rate of contaminant blood cultures could be reduced by using a team of dedicated phlebotomists. Comparisons were made between adult patients requiring blood cultures for suspected bacteremia on medical and surgical units before and after the introduction and withdrawal of a dedicated blood culture team. The results showed that a significant reduction in the contaminant blood culture rate was achieved by the blood culture team (P < 0.001; chi(2) test). Therefore, in our experience, the rate of contaminant blood cultures can be reduced in a teaching hospital by using a team of dedicated phlebotomists. Calculations made with our data and those published by others suggest that cost savings from reducing false-positive blood cultures are greater than the cost of the blood culture team. 相似文献
2.
Lucy Yardley David Papo Adolfo Bronstein Michael Gresty Mark Gardner Nilli Lavie Linda Luxon 《Neuropsychologia》2002,40(4):373-383
The aim of this series of experiments was to determine whether attention is normally required for continuously processing vestibular information concerning orientation, or is required only when orientation is disrupted (eg by vestibular dysfunction or by conflicting visual and vestibular orientation cues). In the first two studies, healthy subjects were passively oscillated, and indicated when they perceived they were passing through their starting position. There was only weak evidence for interference between performance on this 'continuous orientation monitoring task' and on concurrent mental tasks. However, a third study showed that when patients with vestibular imbalance carried out the continuous orientation monitoring task their performance on a concurrent mental arithmetic task was substantially impaired. This dual task interference was correlated with inaccuracy in judging orientation on the continuous orientation monitoring task, which in turn correlated with severity of recent vestibular symptomatology (assessed by questionnaire). In a fourth experiment, disorientation was induced in healthy subjects by rotating the visual field about the line of sight. Bidirectional interference was observed between monitoring orientation (assessed by accuracy in setting a rod to the perceived vertical) and performance of an arithmetic task. Dual task interference was correlated with baseline levels of disorientation induced by the visual field, as indicated by inaccuracy in judging the visual vertical. These findings suggest that monitoring orientation makes significant demands upon cortical processing resources when disorientation is induced, whether the disorientation results from deficient sensory functioning or from ambiguous perceptual information. 相似文献
3.
Ambulatory blood pressure monitoring (ABPM) allows one to evaluate the blood pressure (BP) profile over a 24-hour period in the patient's natural environment. Casual pressure measurements in the physician's office can be affected by alarm reactions, thus causing "white coat" hypertension. ABPM allows one to evaluate these reactions and determine the average pressure and variability of BP along with the effects of physical activity and emotional arousal on BP patterns while at work, at home, and during sleep. Average pressures determined by ABPM are more predictive of target organ involvement and cardiovascular complications of hypertension than casual monitoring of BP in the clinic. The absence of physiologic decline in arterial pressure during sleep is associated with increased prevalence of atherosclerotic complications and left ventricular hypertrophy as well as impairment of the autonomic nervous system. Although further prospective studies are needed to confirm the benefits of home pressure readings and ABPM, ABPM can be helpful in the diagnosis and determination of prognosis and therapeutic responses in a select group of patients. 相似文献
4.
A patient with a sleep-wake cycle greater than 24 h recorded his sleep-onset and wake times for 4 years. During this time the patient found himself unable to maintain a 24-h sleep-wake schedule. The lengths of his sleep-wake periods (subjective days) and his sleep periods were highly variable. Nonetheless, there were certain unexpected regularities in his sleep-wake data, corresponding to fixed clock hours. Across the 4-year period, there were certain clock hours during which sleep onset and waking were likely to occur and certain clock hours that may be considered forbidden zones for sleep, during which the patient rarely either began or ended a sleep period. It is possible that the unexpected regularities resulted from partial entrainment to external cues or from some residual influence of an endogenous ultradian-regulating mechanism. 相似文献
5.
6.
Monoclonal anti-tuberculosis antibodies react with DNA, and monoclonal anti-DNA autoantibodies react with Mycobacterium tuberculosis. 总被引:6,自引:3,他引:6
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Y Shoenfeld Y Vilner A R Coates J Rauch G Lavie D Shaul J Pinkhas 《Clinical and experimental immunology》1986,66(2):255-261
Classical models of experimental autoimmune diseases, such as adjuvant arthritis entail the use of mycobacteria. Furthermore, BCG immunotherapy may be followed by arthritic symptoms. To test the infection-autoimmunity relationship of mycobacteria, we used monoclonal antibodies raised against M. tuberculosis and against DNA. Murine monoclonal anti-TB antibodies were found to react with ssDNA, dsDNA and other polynucleotides. Monoclonal anti-DNA autoantibodies derived from patients and mice with SLE bound to three glycolipids shared among all mycobacteria and derived from mycobacterial cell wall. Prior incubation of the antibodies with ssDNA and other polynucleotides or with glycolipid antigens inhibited binding. These results indicate that infecting mycobacteria share antigens with human tissue, thus accounting in part for the production of autoantibodies in mycobacterial infections. 相似文献
7.
Y Shoenfeld R Zamir H Joshua G Lavie J Pinkhas 《European journal of immunology》1985,15(10):1024-1028
Two out of 25 monoclonal anti-DNA autoantibodies that were produced by human-human hybridoma were found to have lymphocytotoxic activity. The antibodies reacted with normal B and T lymphocytes at cold (4 degrees C) as well as at warm (37 degrees C) temperatures. The lymphocytotoxic activity of the monoclonal anti-DNA antibodies could be inhibited by prior incubation of the antibodies with either polynucleotides, e.g. poly(I), poly(dT) or anti-idiotypic antibodies, that had been raised against a dominant anti-DNA antibody. The cross-reactivity between nuclear material and lymphocyte membrane raises the question whether these apparently diverse materials have a shared epitope. The cross-reactivity between anti-DNA antibodies and lymphocyte membrane may account in part for the lymphopenia observed in systemic lupus erythematosus patients. 相似文献
8.
We ran two experiments to investigate whether peripheral arterial tone reflects changes in mental effort. Finger pulse wave amplitude, interpulse interval, and pulse variability in the mid- and high-frequency bands were recorded by means of a newly developed finger plethysmograph during both rest and cognitive performance. Using a modified version of the Sternberg memory task, we selectively manipulated either the difficulty of the task (Experiment 1) or the subjects' level of engagement in the task (Experiment 2). We found a significant difference in finger pulse wave amplitude between rest and task periods, suggesting that the measure reflects changes in sympathetic activity due to task engagement. In addition, our results suggest that reduced pulse wave amplitude, signaling vasoconstriction, occurs when subjects are investing effort. 相似文献
9.
Andrew Elagizi Carl J. Lavie Evan OKeefe Keri Marshall James H. OKeefe Richard V. Milani 《Nutrients》2021,13(1)
Interest in the potential cardiovascular (CV) benefits of omega-3 polyunsaturated fatty acids (Ω-3) began in the 1940s and was amplified by a subsequent landmark trial showing reduced CV disease (CVD) risk following acute myocardial infarction. Since that time, however, much controversy has circulated due to discordant results among several studies and even meta-analyses. Then, in 2018, three more large, randomized trials were released—these too with discordant findings regarding the overall benefits of Ω-3 therapy. Interestingly, the trial that used a higher dose (4 g/day highly purified eicosapentaenoic acid (EPA)) found a remarkable, statistically significant reduction in CVD events. It was proposed that insufficient Ω-3 dosing (<1 g/day EPA and docosahexaenoic acid (DHA)), as well as patients aggressively treated with multiple other effective medical therapies, may explain the conflicting results of Ω-3 therapy in controlled trials. We have thus reviewed the current evidence regarding Ω-3 and CV health, put forth potential reasoning for discrepant results in the literature, highlighted critical concepts such as measuring blood levels of Ω-3 with a dedicated Ω-3 index and addressed current recommendations as suggested by health care professional societies and recent significant scientific data. 相似文献
10.
SUMMARY A positive diagnosis of obstructive sleep apnoea (OSA) is based on a combination of characteristic symptoms and polysomnographic findings. The present study evaluated the specificity and sensitivity of several risk factors, signs and symptoms in predicting an Apnoea Index in 86 patients referred to the sleep laboratory with suspected OSA. All 86 subjects completed a detailed questionnaire, were interviewed, underwent a brief physical examination, and then a whole-night polysomnographic study. Stepwise multiple regression analysis revealed that self reporting on apnoeas, neck circumference index (NCI), age, and a tendency to fall asleep unintentionally, were all significant positive predictors of apnoea index (AI), explaining 41.8% of the variability. The sensitivity of the model for predicting OSA (taking OSA as AI>10) was 92.2%, specificity was 18.2% and the positive predictive value was 76.6%. Raising the cut-off AI values resulted in decreased sensitivity and increased specificity. Applying the predicting equation of AI to another group of 50 patients referred to the sleep laboratory with suspected OSA revealed similar results. However, running the equation on 105 offspring of OSA patients who did not complain of OSA-associated symptoms resulted in 32% sensitivity and 94% specificity in predicting OSA. It is concluded that questionnaires, interviews and physical examination, can only vaguely predict AI, and cannot replace polysomnographic recordings. However, the low rates of false negative in predicting AI > 10, and the low rates of false positive in predicting AI > 50, can be used for specific purposes. 相似文献