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1.
M Caruana R Jones A Lahiri G Brigden E Rodrigues C Dore E B Raftery 《Nuclear medicine communications》1986,7(10):717-728
Five studies were conducted to examine the degree of variability to be expected during the use of the non-imaging nuclear probe (BIOS Inc.) under a variety of clinical conditions. Comparison of the ejection fraction (EF) readings between the nuclear probe and a gamma camera showed good agreement, with the nuclear probe tending to underestimate lower, and overestimate higher camera EF values [mean (S.D.) difference, 0.84% (6.06)]. A comparison of two nuclear probes showed a small mean (S.D.) difference of EF readings of 0.063% (2.26). EF readings obtained in normal subjects 6 weeks apart were reproducible and differed by a mean (S.D.) of 0.23% (4.42). The administration of placebo to 10 normal subjects followed by sequential measurements for 4 h produced EF changes large enough to mimic a clinical effect, the largest hourly change observed being 5.4%, indicating the need for strict placebo control in interventional experiments. Data on four patients with heart failure showed small non-significant EF changes in the 1 h after placebo administration but a wide intra-subject range of ejection time and time to peak filling measurements. This highlights the problem of accurate, reproducible cursor placement in such patients. The nuclear probe is a portable, low cost instrument which produces accurate EF measurements when compared with the gamma camera. 相似文献
2.
Margaret MacDonald Matthew Law John Kaldor Jim Hales Gregory J. Dore 《The International journal on drug policy》2003,14(5-6):353
Objective: To examine the effectiveness of needle and syringe programmes (NSPs) in preventing HIV transmission among injecting drug users (IDUs).Methods: An ecological study design was used to determine change in HIV prevalence among injecting drug users between cities with and without NSPs. Several data sources, such as electronic journal databases, surveillance reports, websites, and index review of relevant journals, were used to identify studies of HIV seroprevalence among IDUs, and presence of NSPs. The rate of change in HIV prevalence was estimated by regression analysis.Results: There were 778 years of data from 99 cities globally included in the analysis. HIV prevalence decreased by 18.6% per annum in cities that introduce NSPs, and increased by 8.1% in cities that had never introduced NSPs (mean difference −24.7% [95% CI: −43.8, 0.5%], P=0.06). The mean difference was –33% when comparison was weighted to one over the variance of the regression estimator (29% decrease in cities with NSPs and 5% increase in cities without NSPs, P<0.001). When analysis was restricted to cities with first HIV seroprevalence less than 10%, the average annual change in seroprevalence was 18% lower in cities with NSPs (P=0.03).Conclusions: Despite the inherent limitations within an ecological study design, the study provides additional evidence that NSPs reduce transmission of HIV infection. The rapid spread of HIV among IDU populations and increasing rates of injecting in many countries calls for scaling up of NSPs as well as other harm reduction strategies. 相似文献
3.
D Dore 《Physical therapy》1987,67(6):964-966
The purpose of this study was to examine the effect of the Medicare prospective payment system on the utilization of physical therapy for patients served by Medicare. The total number of inpatient and outpatient physical therapy referrals and the percentage of physical therapy Medicare referrals from January 1981 through May 1985 for the 336 acute care beds in the county selected for this study were analyzed. The results indicated that acute care inpatient and outpatient physical therapy Medicare referrals have increased significantly since the implementation of the diagnostic related group system. The results indicate that physical therapy is being used increasingly to rehabilitate patients within the time and economic constraints established by the Medicare prospective payment system. 相似文献
4.
Ruprecht Nitschke Charles Pratt Michael Harris Jeffrey Krischer Teresa J. Vietti Holcombe Grier Willem Kamps Stuart Toledano 《Investigational new drugs》1992,10(2):93-96
CHIP (325 mg/M2), a second generation cisplatin derivative, was administered intravenously every 3 weeks to 85 pediatric patients with recurrent sarcomas (19), osteosarcomas (20), neuroblastoma (23), germ cell tumors (10), and other malignant tumors (7). Thirty-eight of them had been previously exposed to cisplatin. Partial remissions were only observed in 3 of 23 (13% SE=7%) patients having neuroblastoma. Severe thrombocytopenia (65%) and neutropenia (35%) were the dose limiting factors. 相似文献
5.
Alexander R Grier Katharine L Grier 《The Journal of the Canadian Chiropractic Association》1992,36(1):22-28
Chiropractic fee negotiations in Saskatchewan utilize the Chiropractic Compensation Review Committee with recourse to the Chiropractic Consultation Committee. Health care professionals who practise on a fee for service basis provide the government with a budgetary problem. Although the fees are set, the health care provider can determine his own income by deciding how many visit services he/she wishes to provide. In the fiscal years 1981-82 to 1990-91, chiropractors earned $699.00 per year more than one would expect given the increases in fee schedules. Each chiropractor earned $2,329.00 per year more than was necessary to make up for losses due to inflation. The allegation that unnecessary treatments were performed on patients is countered by analysis of the services per discrete patient values by mode of practice. The increased earnings of chiropractors was accomplished by treating an increasing percentage of the population who sought health care. Comparative information was obtained from the four western provinces. 相似文献
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Advanced malignant ovarian cancers are treated, after initial surgery, with first-choice mono/polychemotherapy, the response to which is evaluated by means of second-look laparotomy. The poor prognostic value of second-look results, the incidence of false negatives, the lack of valuable second-choice therapies, and the high incidence of complications after repeated interventions, lead to the testing of diagnostic imaging modalities--especially CT and tumor markers (Ca 125 and Ca 15-3). To define their actual clinical value, CT and serum assays of Ca 125 and Ca 15-3 have been performed on 32 treated patients affected with ovarian cancers (stages II-IV), who were clinically free of disease. The results have been compared with second-look pathology, but especially with patient follow-up (min. 24 months). Second-look laparotomy yielded a high number of false negatives (9/22 = 41%); moreover, many important/severe complications were observed. Thus, its value appears to be questionable. CT exhibited high positive predictive value (76.9% over the 24-month follow-up); high for both Ca 125 and Ca 15-3 (100% respectively, at 24-month follow-up) thus, few false positives were observed. Moreover CT, having higher sensitivity (55.5%) than Ca 125 (11.5%) and Ca 15-3 (27.7%), has greater diagnostic capabilities, especially when the lesion is in extraperitoneal location. 相似文献
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Constitutional rearrangements of chromosome 22 as a cause of neurofibromatosis 2 总被引:2,自引:0,他引:2
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