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991.
People with cognitive impairments often cannot effectively recall and articulate experiences, feelings, and perceptions. Therefore, interviewing them can be fraught with pragmatic and methodological difficulties. Given this situation, the authors' experience in a study on the allocation of rehabilitative services to survivors of traumatic brain injury is discussed. Participants had physiological impairments affecting their ability to focus on interview questions. The authors discuss the unique challenges, including participants' recall of events, intolerance to stimuli, and image management and offer strategies for mitigating these concerns. The traditional view that reality is captured only in the subjective accounts of articulate people who can remember events in a precise and reflective manner is challenged. 相似文献
992.
993.
Paterson R 《Health affairs (Project Hope)》2002,21(3):70-79
Since 1996 New Zealand has had a Code of Patients' Rights enforceable by complaints to an independent ombudsman. Patients are entitled to receive health care of an appropriate standard, to give informed consent, and to complain to a health commissioner about perceived malpractice. The commissioner investigates and reports on complaints, recommends practice changes by providers, is a gatekeeper to discipline by professional boards, and acts as a public advocate for patient safety. In this paper the current commissioner describes New Zealand's experience with the patients' complaints system and discusses the implications for the quality of health care. 相似文献
994.
995.
In the queue for coronary artery bypass grafting: patients' perceptions of risk and 'maximal acceptable waiting time'. 总被引:2,自引:0,他引:2
H Llewellyn-Thomas E Thiel M Paterson D Naylor 《Journal of health services research & policy》1999,4(2):65-72
OBJECTIVES: To elicit patients' maximal acceptable waiting times (MAWT) for non-urgent coronary artery bypass grafting (CABG), and to determine if MAWT is related to prior expectations of waiting times, symptom burden, expected relief, or perceived risks of myocardial infarction while waiting. METHODS: Seventy-two patients on an elective CABG waiting list chose between two hypothetical but plausible options: a 1-month wait with 2% risk of surgical mortality, and a 6-month wait with 1% risk of surgical mortality. Waiting time in the 6-month option was varied up if respondents chose the 6-month/lower risk option, and down if they chose the 1-month/higher risk option, until the MAWT switch point was reached. Patients also reported their expected waiting time, perceived risks of myocardial infarction while waiting, current function, expected functional improvement and the value of that improvement. RESULTS: Only 17 (24%) patients chose the 6-month/1% risk option, while 55 (76%) chose the 1-month/2% risk option. The median MAWT was 2 months; scores ranged from 1 to 12 months (with two outliers). Many perceived high cumulative risks of myocardial infarction if waiting for 1 (upper quartile, > or = 1.45%) or 6 (upper quartile, > or = 10%) months. However, MAWT scores were related only to expected waiting time (r = 0.47; P < 0.0001). CONCLUSIONS: Most patients reject waiting 6 months for elective CABG, even if offered along with a halving in surgical mortality (from 2% to 1%). Intolerance for further delay seems to be determined primarily by patients' attachment to their scheduled surgical dates. Many also have severely inflated perceptions of their risk of myocardial infarction in the queue. These results suggest a need for interventions to modify patients' inaccurate risk perceptions, particularly if a scheduled surgical date must be deferred. 相似文献
996.
J Zeng Z Zhang C A Paterson S Ferguson-Yankey M C Yappert D Borchman 《Experimental eye research》1999,69(3):323-330
Lens lipid composition and lipid hydrocarbon chain structure change with age, region and cataract. Since the lens Ca(2+)-ATPase pump is important to the maintenance of calcium homeostasis and lens clarity, muscle sarcoplasmic reticulum Ca(2+)-ATPase was reconstituted with bovine lens lipids and dihydrosphingomyelin, the rare and major phospholipid of the human lens. Ca(2+)-ATPase activity was found to be about 5 times lower when the pump was reconstituted into dihydrosphingomyelin or lens lipids compared to native sarcoplasmic reticulum lipids. The addition of cholesterol to levels ranging from 13-53 mole%, had no affect on reconstituted Ca(2+)-ATPase activity. Ca(2+)-ATPase activity correlated with the degree of hydrocarbon chain saturation. The greater levels of saturation are a consequence of the high sphingolipid content in the reconstituted systems. These data support the hypothesis that changes in lens lipid composition or structure could affect Ca(2+)-ATPase activity in human lenses. Because the mechanisms governing Ca(2+)-ATPase activity in vivo are much more complex than in these simple reconstituted systems, this study represents an initial step in the elucidation of the relationships of endogenous membrane lipid composition-structure and function. 相似文献
997.
998.
PURPOSE: To determine the effect of alpha-crystallin binding on lens membrane lipid characteristics and the stability of Ca2+ -ATPase activity when challenged with H2O2 or elevated temperatures. METHODS: Alpha-Crystallin binding to muscle sarcoplasmic reticulum membranes was quantified using a centrifugation protocol. Alpha-Crystallin binding to lens epithelial lipids was measured by a fluorescence energy transfer technique. Lipid phase transition temperature and lipid order was measured using fluorescence spectroscopy. Ca2+ -ATPase activity was measured using classical biochemical assays. RESULTS: The main phase transition temperatures of multilamellar vesicles composed of sphingomyelin or lipids extracted from bovine lens were 40 degrees C and 20 degrees C, respectively. In the presence of saturating amounts of alpha-crystallin, the phase transition temperature and lipid order of both sphingomyelin and lens lipid membranes remained almost the same as that without alpha-crystallin. The interaction of alpha-crystallin and lipid is likely to be restricted to the membrane surface. The binding of alpha-crystallin did not influence the oxidative or thermal inactivation of the Ca2+ -ATPase pump. CONCLUSION: Alpha-Crystallin-lens membrane binding does not protect the Ca2+ -ATPase pump from thermal derangement or oxidation by H2O2. 相似文献
999.
Andrew D. Paterson David M.J. Naimark Jian Huang Celine Vachon Arturas Petronis Richard A. King V. Elving Anderson Thomas A. Sellers 《Breast cancer research and treatment》1999,55(1):21-28
Genetic anticipation is characterized by an earlier age of disease onset, increased severity, and a greater proportion of affected individuals in succeeding generations. The discovery of trinucleotide repeat expansion (TRE) mutations as the molecular correlate of anticipation in a number of rare Mendelian neurodegenerative disorders has led to a resurgence of interest in this phenomenon. Because of the difficulties presented to traditional genetics by complex diseases, the testing for genetic anticipation coupled with TRE detection has been proposed as a strategy for expediting the identification of susceptibility genes for complex disorders. In the case of breast cancer, a number of previous studies found evidence consistent with genetic anticipation. It is known that a proportion of such families are linked to either BRCA1 or BRCA2, but no TRE mutations have been identified. It has been shown that the typical ascertainment employed in studies purporting to demonstrate genetic anticipation combined with unadjusted statistical analysis can dramatically elevate the type I error. We reexamine the evidence for anticipation in breast cancer by applying a new statistical approach that appears to have validity in the analysis of anticipation to data ascertained from a recent followup of a large prospective cohort family study of breast cancer. Using this approach, we find no statistically significant evidence for genetic anticipation in familial breast cancer. We discuss the limitations of our analysis, including the problem of adequate sample size for this new statistical test. 相似文献
1000.
A spectrum of acute osteomyelitis and septic arthritis seen in children was studied, identifying four major groups, each with a different clinical presentation and different expected prognosis: (1) the usual group of osteomyelitis with a 10% incidence of poor results; (2) neonatal osteomyelitis (10% of osteomyelitis) with 25% poor results; (3) a group of severely ill patients with disseminated staphylococcal disease (10% of osteomyelitis) with 13% mortality and 38% poor results; and (4) the usual group of septic arthritis, with 5% poor results. Almost all cases of osteomyelitis were due to Staphylococcus aureus except in the neonatal group, where 28% were due to -haemolytic streptococci. Surgical drainage was performed in 91% of the usual osteomyelitis cases, in all with disseminated staphylococcal disease, and in 88% of babies with neonatal osteomyelitis, i.e. all the cases involving a joint. Cloxacillin was the drug of choice in osteomyelitis. In septic arthritis Staph. aureus was cultured in 29%, Haemophilus influenzae in 18%, streptococcus in 12%, pneumococcus in 6%, and no growth in 33%. Open arthrotomy was performed in all cases. Cloxacillin was used for cases infected with Staph. aureus, ampicillin for H. influenzae, and penicillin for streptococcal and pneumococcal infections.
Offprint requests to: EB Hoffman 相似文献