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排序方式: 共有1300条查询结果,搜索用时 9 毫秒
971.
N Goudsouzian S Chakravorti W Denman A Schwartz HS Yang DR Cook 《Canadian Metallurgical Quarterly》1997,44(9):955-962
PURPOSE: This study was designed to evaluate pharmacodynamically and pharmacokinetically if the cis-cis isomer of mivacurium contributed to neuromuscular block during prolonged infusions lasting more than four hours in young adult and elderly (> 60 yr) patients. METHODS: The mechanomyogramic neuromuscular response of the adductor pollicis was recorded in 32 adults 18-59 yr. and 19 elderly (> 60 yr.) patients during N2O:O2:opioid anaesthesia. The mivacurium infusion rate was adjusted to maintain single twitch depression at 95 +/- 4% of control. Blood samples were taken every 30 min to determine the plasma concentration of cis-cis isomer of mivacurium. At the end of the surgical procedure, patients were allowed to recover spontaneously to at least 25% of control twitch response. RESULTS: The mean mivacurium infusion requirement to maintain 97 +/- 1 (mean +/- SD)% depression of the twitch response was 6.0 +/- 0.4 micrograms.kg-1.min-1 in young adults, and 4.3 +/- 0.3 micrograms.kg-1.min-1 in elderly patients (P < 0.001). The infusion requirement in patients with low plasma cholinesterase activity was the lowest 2.4 +/- 1.2 micrograms.kg-1.min-1. Plasma cis-cis isomer concentrations reached peak levels within one-two hours and remained relatively constant throughout the duration of infusion even in patients with low cholinesterase activity. There was no relationship between duration of infusion, plasma concentrations of cis-cis isomer and the early recovery indices of mivacurium (up to 25%). Neuromuscular transmission recovered adequately with or without antagonism in all patients. CONCLUSION: When the mivacurium infusion was titrated to maintain 95 +/- 4% twitch depression, the plasma concentration of the cis-cis isomer did not increase during prolonged infusions (four hours) and neuromuscular transmission recovers satisfactorily. 相似文献
972.
Selection of tumor antigens as targets for immune attack using immunohistochemistry: II. Blood group-related antigens 总被引:1,自引:0,他引:1
S Zhang HS Zhang C Cordon-Cardo VE Reuter AK Singhal KO Lloyd PO Livingston 《Canadian Metallurgical Quarterly》1997,73(1):50-56
The Vietnam Era Twin (VET) Registry includes 14,800 male twins born 1939-55 and in military service in 1964-75. A mailed health survey including the Jenkins Sleep Questionnaire was sent to 11,959 members and 8,870 (74.2%) provided responses on the frequency of sleep problems in the previous month. Prevalence of those experiencing conditions at least 1 day per month was 67.2% for waking often, 61.5% for waking tired/worn out, 48.1% for trouble falling asleep and 48.6% for awakening early. Ordinal logistic regression analysis was used to estimate sleep problems from demographic, behaviour and lifestyle characteristics, and morbid conditions. Black (vs. white) race, older age, church/religious group participation, social support, employment, cigarette smoking, light physical activity, and strenuous physical activity were associated with lower risk of one or more sleep problems. Eleven morbid conditions with a prevalence of 1% or more, coffee consumption, heavy alcohol consumption, and Framingham Type A behaviour pattern were associated with a higher risk of sleep problems. These analyses suggest that sleep problems may be one of the mechanisms relating reduced quality of life to many physical and behavioural characteristics. Fortunately, a number of the risk factors associated with sleep problems are lifestyle characteristics which, if modified, may reduce sleep problems. 相似文献
973.
BACKGROUND: To assess the clinical features and therapeutic outcomes of adult Klebsiella pneumoniae (KP) meningitis. METHODS: Thirty-two adult patients with KP meningitis were included in this study. Their clinical features, the outcomes with the third generation cephalosporin (moxalactam, cefotaxime, ceftazidime) treatment and prognostic factors were analyzed. RESULTS: These patients' diseases were predominantly community-acquired. Males outnumbered females (3:1). Diabetes mellitus (DM) was the most common underlying disease, followed by other debilitating diseases such as liver cirrhosis, neoplasm and end-stage renal disease (ESRD). Patients with spontaneous meningitis had a more fulminant course with a higher prevalence of bacteremia, shock and death (66%). Metastatic septic abscess was frequent (19%). Among the 21 patients who received initial appropriate antimicrobial therapy (IAAT), 2 took cefotaxime and 1 died; 13 took moxalactam of whom 5 died; and 6 took ceftazidime of whom 3 died. All of the other 11 patients who did not receive IAAT died. CONCLUSIONS: The clinical features of KP meningitis are various and indistinguishable from other form of bacteria meningitis. Most of the patients with KP meningitis are associated with underlying medical problems, such as diabetes mellitus and liver cirrhosis. Many factors, including septic shock, bacteremia, high cerebrospinal fluid lactate concentration, and IAAT, might influence the prognosis. In spite of a high mortality rate, however, IAAT is mandatory to improve the overall survival rate. 相似文献
974.
CC Overtoom MN Verbaten C Kemner JL Kenemans H van Engeland JK Buitelaar G Camfferman HS Koelega 《Canadian Metallurgical Quarterly》1998,37(9):977-985
OBJECTIVES: First, to differentiate between inattention and impulsivity based on type of errors made in the AX version of the Continuous Performance Task (CPT), and second, to investigate whether differences in performance between children with attention-deficit hyperactivity disorder (ADHD) and normal controls also occur in specific forms of brain activity, namely event-related potentials (ERPs), presumably related to inattention and impulsivity or inhibition. METHOD: Sixteen ADHD and 16 normal control children performed the CPT-AX. ERPs were recorded at occipital (Oz), parietal (Pz), central (Cz), and frontal (Fz) leads. RESULTS: The ADHD children had a higher CPT-Inattention score and showed smaller parietal positive waves at a latency of approximately 300 msec in reaction to target stimuli, target P3s, likewise indicating less attention. In contrast, they showed neither higher CPT-Impulsivity nor a smaller frontocentral negative wave at about 200 msec (N2); the N2 is generally seen as reflecting inhibition. A subgroup of children with ADHD and oppositional defiant disorder (n = 6) had smaller N2 waves than controls, however. CONCLUSIONS: The ADHD group studied showed deficits in attention but not in impulsivity (or inhibition). 相似文献
975.
SP McKee SN Watamaniuk JM Harris HS Smallman DG Taylor 《Canadian Metallurgical Quarterly》1997,37(15):2047-2055
It has been suggested that breaking camouflage is one of the major functions of stereopsis (Julesz, 1971). In this study, we found that stereopsis is less effective in breaking camouflage for moving targets than for static ones. Observers were asked to detect a single dot moving on a straight trajectory amidst identical noise dots in random motion. In the three-dimensional (3D) condition, the noise dots filled a cylindrical volume 5.7 cm in height and diameter; the trajectory signal dot moved on an oblique 3D trajectory through the center of the cylinder. In the two-dimensional (2D) control condition, observers viewed one half-image of the 3D cylinder binocularly. Surprisingly, trajectory detection in the 3D condition was only slightly better than in the 2D condition. Stereoscopic tuning for motion detection was also measured with a novel target configuration in which the random motion noise was presented in two depth planes that straddled the fixation plane where the trajectory target was presented. As the disparity between the noise planes and the fixation plane was increased, trajectory detection improved, reaching a peak between 6 and 12 arcmin, and then declining to the 2D level at larger disparities, where the noise became diplopic. Similar tuning measurements were made for detecting a static pattern, a string of five aligned dots presented in the fixation plane between two planes of static noise dots. Adding disparity to the noise planes produced a far greater improvement in static detection than in motion detection, for a comparable range of disparities (1.5-12 arcmin). We speculate that the temporal characteristics of the stereo system are not well suited for responding to moving targets, with the result that stereo does not greatly enhance motion detection in noise. 相似文献
976.
977.
Postpartum depression affects 10 to 15 percent of all mothers. A study of 725 obstetric nurses and 204 obstetricians was conducted using a reliable two-factor scale to measure their knowledge and awareness of postpartum depression. Nurses were more aware than physicians of the emotional impact of postpartum depression. Nurses who demonstrated more empathy and who believed education of postpartum depression does not increase a mother's risk were more aware of the postpartum phenomenon than nurses who were less empathic and who did not hold the same belief. Younger and women physicians recognized the psychosocial antecedents to postpartum depression to a greater degree than did older and men physicians. These findings offer potential use in the training of perinatal health care professionals and in the education of pregnant women about postpartum depression. 相似文献
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