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91.
Tracy Roberts BSc MPhil RGN Stirling Bryan BSc MSc Chris Heginbotham BSc MSc MA & Alison McCallum MB ChB MSc FFPHM 《Health expectations》1999,2(4):235-244
Background Public involvement in health care decision making and priority setting in the UK is being promoted by recent policy initiatives. In 1993, the British Medical Association called for public consultation where rationing of services was to be undertaken. The approach to priority setting advocated by many health economists is the maximization of quality adjusted life years (QALYs). Typically, for a particular health care programme, the QALY calculation takes account of four features: (1) the number of patients receiving the programme, (2) the survival gain, (3) the gain in quality of life and, (4) the probability of treatment success. Only one feature, that relating to quality of life, is based upon public preferences. If the QALY is to be used as a tool for health care resource allocation at a societal level then it should incorporate broader societal preferences.
Methods This study used an interview-based survey of 91 members of the general public to explore whether the traditional QALY maximization model is a good predictor of public responses to health care priority setting choices.
Results and conclusions Many respondents did not choose consistently in line with a QALY maximization objective and were most influenced by quality of life concerns. There was little support for health care programmes that provided a prognostic improvement but left patients in relatively poor states of health. The level of respondent engagement in the survey exercise was not sensitive to the provision of supporting clinical information. 相似文献
Methods This study used an interview-based survey of 91 members of the general public to explore whether the traditional QALY maximization model is a good predictor of public responses to health care priority setting choices.
Results and conclusions Many respondents did not choose consistently in line with a QALY maximization objective and were most influenced by quality of life concerns. There was little support for health care programmes that provided a prognostic improvement but left patients in relatively poor states of health. The level of respondent engagement in the survey exercise was not sensitive to the provision of supporting clinical information. 相似文献
92.
J. Byrne MB BCh FRCSI J. W. Hallett Jr. MD C. F. Kollmorgen MD M. M. Gayari BS W. Davies MD FRCSC 《Annals of vascular surgery》1996,10(2):156-165
Our aim was to examine the feasibility of a totally laparoscopic insertion of a bifurcated aortofemoral bypass graft in a canine model and to compare the surgical results with those in control animals undergoing standard grafting and laparoscopic-assisted bypass procedures. Using a six-port approach, we exposed and cross clamped the aorta, tunneled a bifurcated Dacron graft, and performed an end-to-end aortic anastomosis while maintaining pneumoperitoneum by means of CO2. Proximal anastomoses were performed with 4/0 double-ended continuous Prolene sutures and distal anastomoses were performed through standard groin incisions. Total operating and aortic cross-clamp times were measured as was the total blood loss for each procedure. Clinical outcome was also documented. Eight female laboratory-bred hounds underwent successful totally laparoscopic aortobifemoral bypass grafting, eight underwent open grafting, and eight underwent laparoscopic-assisted bypass. Mean operating time was 193 minutes in the animals undergoing totally laparoscopic insertion vs. 156 minutes in the open group and 180 minutes in the laparoscopic-assisted group. Aortic cross-clamping time was also significantly longer at 87 minutes vs. 43 minutes (p < 0.001)=" in=" the=" totally=" laparoscopic=" group,=" but=" blood=" loss=" was=" less.=" all=" eight=" laparotomy=" and=" laparoscopic-assisted=" dogs=" were=" still=" alive=" with=" no=" complications=" at=" 28=" days,=" whereas=" three=" of=" the=" eight=" in=" the=" totally=" laparoscopic=" group=" showed=" evidence=" of=" temporary=" paraplegia.=" this=" experimental=" study=" demonstrates=" that=" a=" totally=" laparoscopic=" approach=" can=" be=" used=" to=" insert=" a=" bifurcated=" aortofemoral=" bypass=" with=" a=" proximal=" end-to-end=" anastomosis=" but=" currently=" does=" not=" save=" time=" and=" may=" increase=" the=" risk=" of=" neurologic=">Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995. 相似文献
93.
The success of vertical gastroplasty may be jeopardized by gastric leakage or ulceration due to failure of the technique.
Reports of band erosion and staple-line leakage have led us to seek technical improvements to reduce technical failures. We
describe a modification to the technique of band placement and a manoeuvre to aid the placement of staples when the TA90 staple
gun is used. 相似文献
94.
Frydenberg HB 《Obesity surgery》1991,1(3):315-317
Many forms of gastric banding have been described and high reoperation rates reported. These can be mainly attributed to excess
vomiting associated both with and without stenosis. Reflux oesophagitis and the ‘sump’ effect may be other causes. This paper
examines the problems associated with banding leading to revisional surgery and introduces a new technique, ‘fundal supporting
suture’, to correct these problems. Preliminary results on 126 bandings without the modification and 22 with the modification
are presented. 相似文献
95.
N M Leahy 《The Nursing clinics of North America》1991,26(4):971-983
The body-system alterations that occur in a patient who has suffered a cerebrovascular insult are multiple and often permanent. Even the "uncomplicated" stroke patient presents a challenge for multifaceted nursing care. The patient who develops complications secondary to the event poses even more complex issues for medical and nursing management. The proclivity for complications to evolve varies with age, brain areas involved, whether the event is hemorrhagic or nonhemorrhagic in nature, and the presence of concomitant systemic disease. Today's professional nurse has access to current technology and possesses the assessment skills and knowledge that enable early recognition of signs and symptoms foreboding potentially disastrous complications. 相似文献
96.
The hypothesis of physician-induced demand is examined empirically in a model where variation in consumer information affects health-care utilization. A theoretical framework is posited under which demand-inducing physicians will provide more services, ceteris paribus, to their medically uninformed patients. Using data from the CHAS-NORC National Survey of Access to Medical uninformed patients. Using data from the CHAS-NORC National Survey of Access to Medical Care 1975-1976, physician office visit demand equations are estimated. The key finding is that medical professionals and their families are as likely, if not more likely, to visit physicians as other people, controlling for sociodemographic factors, price factors, access to care factors and perceived health status. 相似文献
97.
David E. Leahy 《Drug Discovery Today: BIOSILICO》2004,2(2):78-84
The ‘virtual human’ refers to simulation models based on explicit mathematical models of mammalian physiology. When applied to pharmacokinetics (PK), the virtual human embodies models that can be parameterised for different species, different individuals and populations of individuals, and that allow simulation of PK from measured and/or predicted in vitro properties. The models are independent of the properties of any specific drug, and can be used for the prediction of drug behaviour in specific human individuals and in pre-clinical species. The hope is that these models will allow the prediction of PK throughout the drug discovery and development process, enabling effective targeting of synthetic chemistry efforts to compounds with the required therapeutic effect, careful evaluation of multiple candidates for development, assessment of the potential for drug-drug interactions, evaluation of multiple formulations, efficient clinical trial design and other benefits, including reduction of animal usage in drug discovery. However, we believe that the biggest impact on drug discovery productivity would accrue from achieving two clear objectives: an estimate of human in vivo activity on every compound synthesised and a reliable prioritisation, based on predictions of human in vivo activity, for the next round of synthesis. It is realistic to believe that the benefits of delivering these objectives could, through shortening the time to decision and increasing the chance of success, lead to a five- to ten-fold increase in discovery output. It is also now possible to demonstrate that a combination of virtual human simulation software and industrial-scale absorption, distribution, metabolism and elimination (ADME) testing can deliver both of these objectives. 相似文献
98.
Increased placental apoptosis in intrauterine growth restriction 总被引:2,自引:0,他引:2
Stephen C. Smith MB ChB Philip N. Baker DM E.Malcolm Symonds MD 《American journal of obstetrics and gynecology》1997,177(6):1395-1401
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401) 相似文献
99.
MB Popli N Mehta VS Nijhavan V Popli 《Journal of Medical Imaging and Radiation Oncology》1998,42(3):256-257
Congenital tuberculosis is a rare disease. The non-specific nature of presenting signs and symptoms (because of the lack of host response) and the fatal outcome in the absence of early therapy all underscore the importance of early diagnosis and treatment in infants. Recognition requires awareness that tuberculosis at this age has manifestations not found in older children. Here a case of congenital tuberculosis is presented, where changes were confined only to the thorax. Tuberculosis in the mother could be diagnosed only retrospectively. 相似文献
100.