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991.
992.
C Biddle 《Canadian Metallurgical Quarterly》1993,61(2):170-4; quiz 175
Mechanical ventilation has become commonplace in critical care environments and a number of improvements designed to improve the interface between patient and machine are finding their way into the operating room as well. Strategies which are discussed include differential lung ventilation, inspiratory pause, inverse ratio ventilation, mandatory minute volume, pressure support ventilation, and airway pressure release ventilation. These strategies are discussed individually in terms of both their theoretical and clinical utility. A user-friendly classification of ventilatory approaches based on the rate of breathing is also provided as is treatment of the issue of the cardiovascular effects of positive end-expiratory pressure. Conditions which increase ventilatory demand in mechanically ventilated patients are reviewed, as these require consideration when caring for the patient receiving mechanical ventilation. While conventional positive pressure approaches are suitable for the majority of patients who present for anesthesia and surgery, patients with significant pulmonary dysfunction should be availed the newer approaches to management when possible. This will only become feasible when practitioners recognize the importance and application of these approaches and urge their introduction into operating room based equipment. 相似文献
993.
HE Vi?tor F Klumper RJ Meerman A Brand HH Kanhai 《Canadian Metallurgical Quarterly》1998,18(4):325-331
Histamine is an important mediator in allergic reactions, gastric acid secretions, and neurotransmission in the central nervous system. Basophils and mast cells are the main sources of histamine, which is formed from L-histidine by histidine decarboxylase (HDC). However, the regulatory mechanism of HDC in these cells remains unclear. We examined the regulation of HDC activity and gene expression using a unique human mast cell line, HMC-1, after stimulation with phorbol 12-myristate 13-acetate (PMA) or ionomycin. HDC activity was increased from 52.1+/-0.4 (mean+/-standard deviation) to 154+/-6.9, or 105.6+/-6.2 pmol/min/mg protein (n = 3), 4 hours after stimulation with PMA (10 ng/mL) or ionomycin (10[-6] M). Although actinomycin D had no effect on this increase, cycloheximide completely inhibited the increase caused by these stimuli. The population of HMC-1 cells containing HDC protein was increased after stimulation with either PMA or ionomycin as evaluated by immunocytochemical analysis with anti-HDC antibody as a marker. HMC-1 constitutively expressed HDC mRNA, and its level was not increased with these stimuli. These results suggest that the increase of HDC activity in HMC-1 induced by PMA or ionomycin is regulated at the translational level. 相似文献
994.
995.
Neurological complications of radiotherapy and chemotherapy can affect the central or peripheral nervous system. Most are dose-dependent and constitute a limiting factor in the administration of treatments. Radiation-induced neurological complications are classified as acute, early-delayed or delayed. The most important are radionecrosis and cognitive dysfunction/leukoencephalopathy. Neurotoxicity of chemotherapy is frequent and depends upon dose, type of drugs (especially cisplatin and methotrexate) and their combination with radiotherapy. 相似文献
996.
PJ Kelly CT McDonald GO Neill C Thomas J Niles G Rordorf 《Canadian Metallurgical Quarterly》1998,50(4):1157-1160
Idiopathic thrombotic thrombocytopenic purpura (TTP) is frequently complicated by microinfarcts in cerebral cortex and subcortical white matter. We describe two sisters who suffered massive hemispheric infarction due to thrombosis of the middle cerebral artery main stem during exacerbations of TTP. Acute TTP may be associated with intraluminal thrombosis of large-diameter arteries in addition to arterioles and capillaries. 相似文献
997.
F Lofaso F Goldenberg MP d'Ortho A Coste A Harf 《Canadian Metallurgical Quarterly》1998,113(4):985-991
STUDY OBJECTIVES: To assess the hemodynamic effects of graded arousals during nonrapid eye movement (NREM) sleep in patients with partial upper airway obstruction during sleep without obstructive sleep apnea/hypopnea, overnight beat-to-beat BP was recorded in six patients. SETTING: At the end of each nonapneic obstructive event, EEG responses were graded as follows: grade 2, grade 1, and grade 0 were defined as increased high-frequency EEG lasting >15 s, 3 to 15 s, and no EEG arousals according to the American Sleep Disorders Association, respectively. MEASUREMENTS AND RESULTS: The following were observed during grade 0, 1, and 2 EEG patterns (mean+/-SD): systolic pressure increased by 7.1+/-1.5, 11.7+/-1.9, and 14.2+/-3.4 (p<0.005), respectively; diastolic pressure increased by 4.6+/-0.6, 6.7+/-1.7, and 9.4+/-3.0 (p<0.005), respectively; heart rate increased by 2.9+/-0.4, 3.9+/-2.2, and 8.6+/-4.6 (p<0.005), respectively. CONCLUSIONS: We conclude that nonapneic-nonhypopneic obstructive events are followed by arterial systemic pressure increases whose magnitude varies with the grade of the arousal. 相似文献
998.
The relationship between office size and noise level is one of the most significant, yet least investigated, factors affecting software productivity. According to Tom DeMarco and Tim Lister (1992), US programmers with more than 80 square feet of private, noise-free office space consistently outperform programmers who occupy two- or three-person cubicles. The result was the Santa Teresa Programming Laboratory in San Jose, California, which opened in 1978. The author discusses some requirements of an optimal programming office environment. He considers the effectiveness of home working 相似文献
999.
1000.
INTRODUCTION: Previous work has shown that parents prefer to be present when their children undergo common invasive procedures, although physicians are ambivalent about parental presence. PURPOSE: To determine the effect of a parent-focused intervention on the pain and performance of the procedure, anxiety of parents and clinicians, and parental satisfaction with care. POPULATION: Children younger than 3 years old undergoing venipuncture, intravenous cannulation, or uretheral catheterization. SETTING: Pediatric emergency department of Boston City Hospital. DESIGN: Randomized controlled trial with three groups; parents present and given instructions on how to help their children; parents present, but no instructions given; and parents not present. INTERVENTION: The parents were instructed to touch, talk to, and maintain eye contact during the procedure. RESULTS: A total of 431 parents was randomized to the intervention (N = 153), present (N = 147), and not present (N = 131) groups. The groups were equivalent with respect to measured sociodemographic variables and parents' previous experience in the pediatric emergency department. No differences emerged with respect to pain (3-point scale measured by parent and clinician, and analysis of cry); performance of the procedure (number of attempts, completion of procedure by first clinician, time); clinician anxiety; or parental satisfaction with care. Parents who were present were more likely to rate the pain of the children as extreme/severe (52%) in comparison to clinicians (15%, kappa .07, poor agreement) and were significantly less anxious than parents who were not present. CONCLUSION: Overall, the intervention was not effective in reducing the pain of routine procedures. Parental presence did not negatively affect performance of the procedure or increase clinician anxiety. Parents who were present were less anxious than those who were not present. CLINICAL IMPLICATION: In general, parents have indicated that they want to be present when their children undergo procedures. The results of this study challenge the traditional belief that parental presence negatively affects our ability to successfully complete procedures. We should encourage parents who want to be present to stay during procedures. 相似文献