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81.
Polyphosphate esters were synthesized by interfacial polymerization of 2,5-bis(p-hydroxybenzylidene)cyclopentanone, 2,5-divanillylidenecyclopentanone, 2,6-bis(p-hydroxybenzylidene)cyclohexanone, 2,6-divanillylidenecyclohexanone or 2,7-bis(p-hydroxybenzylidene)cycloheptanone with phenyl phosphorodichloridate. The resulting polymers were characterized by elemental analysis, IR spectroscopy, solubility and viscometry measurements. The thermal properties of the polymers were evaluated by TGA measurements and correlated with their structural units. The crystallinity of all the polyphosphate esters was tested by X-ray analysis. 相似文献
82.
83.
Patients with arteriovenous malformation (AVM)-associated aneurysms are a well-recognized subset of the cerebrovascular disease population. The origin of these dual lesions is likely multifactorial, with hemodynamic stresses having a dominant influence. In most patients who present with hemorrhage, the aneurysm is the usual source. Since aneurysm rupture continues to carry a more significant morbidity and mortality when compared to AVM hemorrhage, the authors recommend that the aneurysm be treated first or simultaneously with the AVM in the majority of cases. Treatment of the AVM first is primarily reserved for patients who have suffered bleeds from resectable AVMs. 相似文献
84.
BACKGROUND AND PURPOSE: The purpose of this study was to determine the intertherapist reliability of judgments of stiffness and pain at L-1 to L-5 made using posteroanterior (PA) central pressure testing. SUBJECTS: Three pairs of manipulative physical therapists with a minimum of 5 years of experience were asked to rate pain and stiffness in a total of 90 patients with low back pain. METHODS: Each pair of therapists assessed 30 patients within their own clinic, using their preferred technique to perform an examination using the PA central pressure test at the five lumbar levels. Each pair of therapists recorded their ratings of pain and stiffness. Reliability of judgments was evaluated by intraclass correlation coefficients (ICC) and percentage of exact agreement scores. RESULTS: The ICC values for pain judgments for the group as a whole ranged from .67 to .72, with agreement scores ranging from 31% to 43%. The ICC values for stiffness judgments ranged from .03 to .37, with agreement scores ranging from 21% to 29%. CONCLUSION AND DISCUSSION: Judgments of stiffness made by experienced manipulative physical therapists examining patients in their own clinics were found to have poor reliability, whereas pain judgments had good reliability. Further investigation of this test is required in order to develop a more reliable method of assessing PA stiffness. 相似文献
85.
Throughout history, nuts have been a staple food providing energy, protein, essential fatty acids, vitamins, and minerals. Today, nuts are classified as part of the USDA Food Guide Pyramid's Meat/ Meat Alternate Group. Foods in this group contribute protein as well as important vitamins and minerals to the diet. Nuts are also being studied for their potential health benefits. Research suggests that there may be a connection between frequent nut consumption and a reduced incidence of coronary heart disease. Thus, tradition and promising scientific evidence combine to support the role of nuts in healthful eating. 相似文献
86.
This paper discusses a process hazard management study of a fuel gas conditioning facility based on stateof-the-art fault tree analysis techniques. This facility lowers the water and hydrocarbon dewpoints of a high pressure fuel gas exposed to frigid temperatures during distribution. Using hazards checklists and guidelines as well as internal reviews, various process hazards were identified for this facility. Computerized fault tree analysis techniques were used to identify the failure sequences which could lead to process hazards, and analysts used these results to evaluate the impact of specific hazards upon process safety. Through recommendations presented in the study, the facility owner gained an increased awareness of potential problems and made modifications to reduce the possibility of a hazardous condition and subsequent catastrophic failure. 相似文献
87.
Memorializes Edwin B. Newman (1908–1989). Newman served as chair of the Department of Psychology at Harvard University from 1948 to 1964. He researched the interaction of the problems of measurement and equipment. His investigations centered on the analysis of language and speech and on the technical challenges involved in their quantification. In 1929 he and Frederick Howell Lewis formed Psi Chi, the national honor society for psychology. He served the American Psychological Association in various capacities, including membership on the Board of Directors and the Publication Committee. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
J Maher F Rutledge H Remtulla A Parkes L Bernardi CF Bolton 《Canadian Metallurgical Quarterly》1995,21(9):737-743
OBJECTIVE: To determine, by retrospective chart analysis, the frequency, type and significance of neuromuscular disorders in patients whose clinical features suggested a neuromuscular cause of failure to wean. BACKGROUND: Failure to wean is a common and difficult problem in critical care units. While a neuromuscular cause may be suspected in some patients, the frequency and type has not been determined utilizing comprehensive electrophysiological studies of limbs and the respiratory system. Such knowledge may aid in patient management and prognosis. METHODS: The clinical setting was a critical care/trauma centre that admits 1500 patients per year, approximately 500 being on ventilators for longer than five days. We analyzed the hospital charts of 40 patients admitted to the unit during three years, whose respiratory assessment suggested a neuromuscular cause for failure to wean from the ventilator. To investigate this possibility, we performed electrophysiological studies of the limbs and also of the respiratory system by phrenic nerve conduction and needle electromyography of the chest wall and diaphragm. The results were compared to 25 healthy controls. RESULTS: 38 of 40 patients (95%) had a neuromuscular disorder: 25--critical illness polyneuropathy, 2--Guillain-Barré syndrome, 4--diabetic and critical illness polyneuropathy, 2--uremic and critical illness polyneuropathy, 10--an abnormality of central drive, 5--unilateral phrenic nerve palsy, 3--a neuromuscular transmission defect, and 5--a primary myopathy. Fifteen (38%) had a combination of disorders. Patients with more severe polyneuropathy took longer to wean, a mean of 136 versus 52 days (p = 0.007). The severity of the polyneuropathy had no effect on mortality. CONCLUSIONS: Electrophysiological studies of limbs and the respiratory system are together valuable in confirming the presence, and identifying the specific type of neuromuscular cause for difficulty in weaning from the ventilator. This information is important in patient management and prognosis. 相似文献
89.
Focal and segmental, but not generalized, myoclonus have been described with human immunodeficiency virus (HIV) infection. We describe three patients with generalized myoclonus and acquired immunodeficiency syndrome (AIDS) dementia complex. In each, myoclonus persisted until death, invariably after a course of a few months. In two patients, myoclonus was elicited by sudden auditory stimuli and resembled a startle response. This form of myoclonus may be subcortical in origin. We suggest that the AIDS dementia complex be included among the causes of myoclonic dementia. 相似文献
90.
M Tavassoli N Brunel R Maher NW Johnson T Soussi 《Canadian Metallurgical Quarterly》1998,78(3):390-391
A significant age dependence of the risk of complete heart block complicating radiofrequency ablation of the AV nodal slow pathway was noticed, with no patients <45 years of age experiencing this complication. 相似文献