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111.
Oku S Nakagawa K Momose T Kumakura Y Abe A Watanabe T Ohtomo K 《Annals of nuclear medicine》2002,16(6):409-416
In the management of rectal cancer after the combined therapy of the radiation and surgical operation, the evaluation of the prognosis is important. Although fluoro- 18-deoxyglucose positron emission tomography (FDG-PET) is considered as a useful tool for evaluation of therapeutic effect of this cancer as well as the other cancers, however, there are few articles that clearly describe the appropriate procedure of the FDG-PET in order to obtain the best prognostic value. The purpose of the present study is to compare several variations of a semi-quantification method, the Standardized Uptake Values (SUV) and to determine the most appropriate parameter, for the prognostic prediction and to propose the quantitative guideline of the FDG-PET. Especially, the authors focused on the SUV after radiotherapy, which had not been considered as a key quantitative value, as it was rather taken as a mere indicator of the therapeutic (radiotherapeutic) effect, not a direct indicator of the prognosis for the cancer itself. METHODS: Forty patients with rectal cancer in the lower rectal region underwent two series of FDG-PET study before and after pre-operative radiotherapy. Their SUVs were calculated from FDG-PET data and compared with the results of the long-term follow-up of the patients as well as with histopathological outcomes. Results: All 40 patients had high FDG uptake before radiotherapy. The mean value of SUV before radiotherapy (SUV1) was 7.6. After radiotherapy, the mean value of SUV (SUV2) decreased to 4.2. There was a significant difference in SUV2 between the groups with and without recurrence (p < 0.05), however, SUVI or SUV ratio (SUV2/SUV1) displayed no significant difference with the incidence of recurrence. CONCLUSION: SUV2 was considered to be a good prognostic indicator for long-term prognosis of rectal cancer patients. SUV1 nor SUV ratio SUV2/SUV1 did not have the equivalent prognostic usefulness. Subsets of patients with SUV2 greater than 3.2 should be observed closely. 相似文献
112.
Berthelsen PG Eldrup N Nilsson LB Rasmussen JP 《Acta anaesthesiologica Scandinavica》2002,46(9):1103-1110
BACKGROUND: The feasibility of thermodilution cardiac output measurements with the more convenient room temperature thermal indicator instead of cold injectates has been repeatedly investigated. However, the issue has not been addressed with the appropriate statistical approach advocated by Altman and Bland. Furthermore, we wished to determine if the incorporation of a second thermistor in the thermodilution catheter, to measure the temperature of the thermal indicator where it is delivered into the right atrium/superior caval vein, would result in more precise cardiac output measurements. METHODS: Fifty patients were randomized to receive a single or dual thermistor pulmonary artery thermodilution catheter. Cardiac output was calculated as the average of four injections of 10 ml of isotonic saline. Precision (2 x SD of differences in replicate measurements) for the two catheters and injectate temperatures, and bias and limits of agreement between measurements, with cold and room temperature injectates, were determined. RESULTS: Precision was (0 degrees C) 0.42 l/min and (20 degrees C) 0.90 l/min, and bias and limits of agreement -0.83 l/min and -1.93-0.27 l/min for the single thermistor catheter. For the dual thermistor system precision was (0 degrees C) 0.34 l/min and (20 degrees C) 0.58 l/min. Bias and limits of agreement were -0.03 l/min and -0.61-0.55 l/min. CONCLUSION: The second thermistor is redundant if cold injectates are used. If one wishes to use room temperature injectates the single thermistor system is inadequate. A dual thermistor catheter is, on the other hand, acceptable. 相似文献
113.
114.
Fuel poverty describes a complex interaction between households with low income and energy inefficiency. The Scottish Executive has charged local Scottish authorities with the task of eradicating fuel poverty by 2016. In order to direct investment and tackle fuel poverty, a local authority must know which areas are more likely to contain fuel poor households. Currently, local area fuel poverty indicators, based on small area statistics, are used to identify target areas. This paper proposes an innovative methodology for refinement of the Scottish Fuel Poverty Indicator using GIS as a framework for integrating census data with georeferenced energy efficiency data on local housing stock. This allows a multi-scale mapping of fuel poverty risk at both a census output area level and an individual dwelling level. The proposed methodology highlights small areas, and households, possibly susceptible to fuel poverty previously masked by the aggregation of statistics to large geographic units. 相似文献
115.
A modification of radiocirculography suitable for the investigation of children suffering from congenital heart disease was developed and tested in 55 children with intracardiac shunts. Comparison of data derived from radiocirculography with the data obtained by conventional cardiac catheterisation showed radiocirculography has a high degree of accuracy when it is used to assess shunt size. Pulmonary arterial and capillary pressures and pulmonary resistance values were derived from radiocirculography findings and compared with those obtained from catheterisation studies: only in children of school age could the two be closely correlated. In cyanotic heart disease morphological analysis of the radiocirculographic curves proved an especially helpful diagnostic aid. The close agreement between the assessment of aortic override when using angiography and radiocirculography was demonstrated. 相似文献
116.
医院药费监控策略与指标 总被引:10,自引:0,他引:10
本文介绍了医院内药费控制的指标及措施:根据现代医疗卫生工作效能的概念,讨论控制医院内药费开支的必要性与重要性,说明临床用药要兼顾疗效与经济学两方面因素,并运用药物经济学的原理与方法评价临床用药,以最低药费获得最佳疗效。 相似文献
117.
H. Brent Clark Hartman Boyd K. Raichle Marcus E. Preskorn Sheldon H. Kenneth B. Larson 《Brain research》1981,208(2):311-323
A small volume (5 μl) common carotid arterial injection method is described for the quantitation of cerebral vascular extraction fractions (Et) of diffusion limited tracer molecules in the rat. The method is a modification of a technique diffusion duced by Oldendorf and widely used for the study of blood-brain barrier phenomena. While the Oldendorf technique has proven valuable for estimating the relative permeabilities of substances, it is limited in measuring Et under conditions of physiologically or pharmacologically altered permeability or blood flow. The method described in this paper — using a small volume (5 μl) common carotid injection, a freely diffusible reference tracer, [14C]butanol, and a 5 sec circulation time — allows for measurements of Et that reflect changes in blood flow and small differences in permeability. The modified method is important for the study of the regulation of cerebral vascular permeability and flow in an inexpensive animal model. 相似文献
118.
Vlahović-Palcevski V Francetić I Palcevski G Novak S Bergman U 《Pharmacoepidemiology and drug safety》2005,14(8):561-566
OBJECTIVE: To evaluate the quality of antimicrobial drug prescribing at a university hospital in the Department of Medicine, by using a new scoring system as a quality indicator. METHODS: Design: a prospective, longitudinal survey, during a 21-week period. The necessity of antimicrobial treatment of all in-patients at the Department of Medicine, to whom new antimicrobials were prescribed, was assessed by using a scoring system based on the presence of signs and symptoms of an infection. If the sum's total score was 3 or more, the antimicrobial treatment was deemed justifiable; if the score was less than 3, the antimicrobial treatment was regarded as questionable. Setting: Department of Medicine (279 hospital-beds) at the University Hospital Center Rijeka, a 1200-patient-bed teaching hospital in Croatia. RESULTS: Antimicrobials were prescribed to 15% of the total patients. They were given as a treatment to 89% of the patients, and in 67% of the cases, this treatment was administered empirically. According to the scoring system, 29% of the patients did not have a justified indication for antimicrobial treatment. CONCLUSION: The proposed quality indicator (scoring system) that we used is a simple method for the quality assessment of antimicrobial use. It has indicated areas that require in-depth analysis. 相似文献
119.
OBJECTIVE: To examine facility variation in data quality of the level of pain documented in the minimum data set (MDS) as a function of level of hospice enrollment in nursing homes (NHs). DATA SOURCE: Clinical assessments on 3,469 nonhospice residents from 178 NHs were merged with On-line Survey Certification and Reporting data of 2000, Medicare Claims data of 2000 and the MDS of 2000-2002. STUDY DESIGN: Using the same assessment protocol, NH staff and study nurses independently assessed 3,469 nonhospice residents. Study nurses' assessments being gold standard, we quantified and compared quality of NH staff's pain rating across NHs with high, medium, or low hospice use. Multilevel models were built to assess the effect of NH hospice use levels on the occurrence of false positive (FP) and false negative (FN) errors in NH-rated "severe pain." PRINCIPAL FINDINGS: Of 178 NHs, 25 had medium and 41 high hospice use. NHs with higher hospice use had lower sensitivities. In multilevel analysis, we found a significant facility-level variation in the probability of FP and FN errors in facility-rated "severe pain." Resident characteristics only explained 4 and 0 percent of the facility variation in FP and FN, respectively; characteristics and locations (state) of NHs further explained 53 and 52 percent of the variance. After controlling for resident and NH characteristics, staff in NHs with medium or high hospice use were less likely to have FP or FN errors in their MDS documentation of pain than were staff in NHs with low or no hospice use. CONCLUSIONS: The examination of data quality of pooled MDS data from multiple NHs is insufficient. Multilevel analysis is needed to elucidate sources of heterogeneity in the quality of MDS data across NHs. Facility characteristics, e.g., hospice use or NH location, are systematically associated with overrated/underrated pain and may bias pain quality indicator (QI) comparisons. To ensure the integrity of QI comparison in the NH setting, the government may need to institute regular audits of MDS data quality. 相似文献
120.
Kuang K Li Y Yiming M Sánchez JM Iserovich P Cragoe EJ Diecke FP Fischbarg J 《Experimental eye research》2004,79(1):93-103
The mechanism of fluid transport across corneal endothelium remains unclear. We examine here the relative contributions of cellular mechanisms of Na+ transport and the homeostasis of intracellular [Na+] in cultured bovine corneal endothelial cells, and the influence of ambient Na+ and HCO3- on the deturgescence of rabbit cornea. Bovine corneal endothelial cells plated on glass coverslips were incubated for 60 min with 10 microm of the fluorescent Na+ indicator SBFI precursor in HCO3- HEPES (BH) Ringer's solution. After loading, cells were placed in a perfusion chamber. Indicator fluorescence (490 nm) was determined with a Chance-Legallais time-sharing fluorometer. Its voltage output was the ratio of the emissions excited at 340 and 380 nm. For calibration, cells were treated with gramicidin D. For fluid transport measurements, rabbit corneas were mounted in a Dikstein-Maurice chamber, and stromal thickness was measured with a specular microscope. The steady-state [Na+]i in BH was 14.36+/-0.38 mM (n = mean+/-s.e.). Upon exposure to Na+ -free BH solution (choline substituted), [Na+]i decreased to 1.81+/-0.20mM (n = 19). When going from Na+ -free plus 100 microm ouabain to BH plus ouabain, [Na+]i increased to 46.17+/-2.50 (n = 6) with a half time of 1.26+/-0.04 min; if 0.1 microm phenamil plus ouabain were present, it reached only 21.78+/-1.50mm. The exponential time constants (min-1) were: 0.56+/-0.04 for the Na+ pump; 0.39+/-0.01 for the phenamil sensitive Na+ channel; and 0.17+/-0.02 for the ouabain-phenamil-insensitive pathways. In HCO3- free medium (gluconate substituted), [Na+]i was 14.03+/-0.11mM; upon changing to BH medium, it increased to 30.77+/-0.74 mm. This last [Na+]i increase was inhibited 66% by 100 microm DIDS. Using BH medium, corneal thickness remained nearly constant, increasing at a rate of only 2.9+/-0.9 microm hr-1 during 3 hr. However, stromal thickness increased drastically (swelling rate 36.1+/-2.6 microm hr-1) in corneas superfused with BH plus 100 microm ouabain. Na+ -free, HCO3- free solution and 100 microm DIDS also led to increased corneal swelling rates (17.7+/-3.6, 14.4+/-1.6 and 14.9+/-1.2 microm hr-1, respectively). The present results are explained by the presence of a DIDS-inhibitable Na+-HCO3- cotransporter and an epithelial Na+ channel, both previously found in these cells. On the other hand, the quantitative picture presented here appears a novelty. The changes we observe are consistent with pump-driven rapid exchange of intracellular Na+, and recirculation of fully 70% of the Na+ pump flux via apical Na+ channels. 相似文献