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81.
The study analyses the technical efficiency of community hospitals in Ukraine during 1997–2001. Hospital cost amount to two-thirds of Ukrainian spending on health care. Data are available on the number of beds, physicians and nurses employed, surgical procedures performed, and admissions and patient days. We employ data envelopment analysis to calculate the efficiency of hospitals and to assess productivity changes over time. The scores calculated with an output-oriented model assuming constant returns to scale range from 150% to 110%. Average relative inefficiency of the hospitals is initially above 30% and later drops to 15% or below. The average productivity change is positive but below 1%; a Malmquist index decomposition reveals that negative technological progress is overcompensated by positive catching-up. 相似文献
82.
Relationship between DNA strand breaks and inhibition of poly(ADP-ribosylation): enhancement of carcinogen-induced transformation 总被引:3,自引:0,他引:3
Kasid Usha N.; Stefanik David F.; Lubet Ronald A.; Dritschilo Anatoly; Smulson Mark E. 《Carcinogenesis》1986,7(2):327-330
Inhibition of poly(ADP-Rib) by benzamide (BA) or 3-aminobenzamide(3AB) for a limited period (i.e., when ADP-ribosylation is elevated)during and shortly following X-ray or MNNG-induced DNA damageof BALB/3T3 cells significantly (3- to 30-fold) enhanced transformationfrequency by these agents. Individual Type III foci isolatedfrom benzamide, X-ray, or X-ray plus benzamide treated cultureswere established and characterized for growth in soft agar andfor tumor induction in nude mice. DNA isolated from representativetransformed lines established as a result of BA, X-ray or X-rayand BA treatments was transfected onto NIH/3T3 cells. Transformationefficiencies ranging from 0.17 to 0.28 foci/ µg of DNAwere observed suggesting the possibility that dominant transforminggene(s) were responsible for the oncogenic phenotype of radiationand benzamide transformed DNA. 相似文献
83.
84.
Alexander E. Miroslavov Nikolay I. Gorshkov Alexander L. Lumpov Anatoly N. Yalfimov Dmitrii N. Suglobov Beverley L. Ellis Rattana Braddock Anne-Marie Smith Mary C. Prescott Richard S. Lawson Harbans L. Sharma 《Nuclear medicine and biology》2009,36(1):73-79
IntroductionThe use of 99mTc-macroggregated albumin for lung perfusion imaging is well established in nuclear medicine. However, there have been safety concerns over the use of blood-derived products because of potential contamination by infective agents, for example, Variant Creutzfeldt Jakob Disease. Preliminary work has indicated that Tc(CO)5I is primarily taken up in the lungs following intravenous administration. The aim of this study was to evaluate the biodistribution and pharmacokinetics of 99mTc(CO)5I and its potential as a lung perfusion agent.Methods99mTc(CO)5I was synthesized by carbonylation of 99mTcO4? at 160 atm of CO at 170°C in the presence of HI for 40 min. Radiochemical purity was determined by HPLC using 99Tc(CO)5I as a reference. 99mTc(CO)5I was administered by ear-vein injection to three chinchilla rabbits, and dynamic images were acquired using a gamma camera (Siemens E-cam) over 20 min. Imaging studies were also performed with 99mTc-labeled macroaggregated albumin (99mTc-MAA) and 99mTcO4? for comparison. 99mTc(CO)5I was administered intravenously to Sprague–Dawley rats, and tissue distribution studies were obtained at 15 min and 1 h postinjection. Comparative studies were performed using 99mTc-MAA.ResultsRadiochemical purity, assessed by HPLC, was 98%. The retention time was similar to that of 99Tc(CO)5I. The dynamic images showed that 70% of 99mTc(CO)5I appeared promptly in the lungs and remained constant for at least 20 min. In contrast, 99mTcO4? rapidly washed out of the lungs after administration. As expected 99mTc-MAA showed 90% lung accumulation. The percentage of injected dose per gram of organ ±S.D. at 1 h for 99mTc(CO)5I was as follows: blood, 0.22±0.02; lung, 12.8±2.87; liver, 0.8±0.15; heart, 0.15±0.01; kidney, 0.47±0.08. The percentage of injected dose per organ ±S.D. at 1 h was as follows: lung, 22.47±2.31; liver, 10.53±1.8; heart, 0.18±0.01; kidney, 1.2±0.17. Tissue distribution studies with 99mTc-MAA showed 100% lung uptake.Conclusion99mTc(CO)5I was synthesized with a high radiochemical purity and showed a high accumulation in the lungs. Further work on the mechanism and optimization of lung uptake of 99mTc-pentacarbonyl complexes is warranted. 相似文献
85.
Akhutina T Foreman N Krichevets A Matikka L Narhi V Pylaeva N Vahakuopus J 《Disability and rehabilitation》2003,25(24):1361-1371
Purpose: To examine the effectiveness of combining virtual environment (VE) instruction with additional desk-top tasks, based on the Luria-Vygotsky methodology, for spatial remediation in children having complex motor disabilities restricting movement.
Method: In Experiment 1, from among children attending for residential rehabilitation, an experimental subgroup had additional spatial training using a VE and corresponding desk-top models. All children were tested at the start and end of training, using four spatial tests. In Experiment 2, larger groups of children (pair-matched for initial performance) were given the same training as in Experiment 1, but experimentals received both VE-based training and supporting tasks designed to improve executive functions and verbal regulation of spatial functioning. Assessment involved a wider range of tests than in Experiment 1.
Results: In Experiment 1, both groups showed improvement at retest, but experimentals showed greater improvement. Children beginning with the lowest level of cognitive performance failed to benefit from the additional training. In Experiment 2 the experimental group made significantly greater improvement than controls, irrespective of initial performance level.
Conclusions: VE-based spatial training is effective for children with complex disabilities, particularly when combined with training that remediates cognitive weaknesses. 相似文献
Method: In Experiment 1, from among children attending for residential rehabilitation, an experimental subgroup had additional spatial training using a VE and corresponding desk-top models. All children were tested at the start and end of training, using four spatial tests. In Experiment 2, larger groups of children (pair-matched for initial performance) were given the same training as in Experiment 1, but experimentals received both VE-based training and supporting tasks designed to improve executive functions and verbal regulation of spatial functioning. Assessment involved a wider range of tests than in Experiment 1.
Results: In Experiment 1, both groups showed improvement at retest, but experimentals showed greater improvement. Children beginning with the lowest level of cognitive performance failed to benefit from the additional training. In Experiment 2 the experimental group made significantly greater improvement than controls, irrespective of initial performance level.
Conclusions: VE-based spatial training is effective for children with complex disabilities, particularly when combined with training that remediates cognitive weaknesses. 相似文献
86.
Lieber CS DeCarli LM Leo MA Mak KM Ponomarenko A Ren C Wang X 《Journal of hepatology》2008,48(2):318-326
BACKGROUND/AIMS: Replacing long-chain triacylglycerols (LCT) with medium-chain triacylglycerols (MCT) reduces alcohol-induced liver injury. Because of the similarity of the pathogenesis of alcohol-induced liver damage and non-alcoholic steatohepatitis (NASH), our aim was to assess whether MCT is also beneficial in NASH. METHODS: We used a rat NASH model in which corn oil (35% of total calories) was isocalorically replaced with MCT. RESULTS: Partial replacement of LCT did not ameliorate hepatic fat accumulation, 4-hydroxynonenal, collagen type I and its mRNA but it increased TNF-alpha and its mRNA (p<0.001). However, in rats given the high-fat diet restricted to 2/3 of the amount they were consuming, these adverse effects decreased, with and without MCT including less liver steatosis and lower triacylglycerols, but without beneficial effects of MCT. When 70% of the fat calories were replaced with MCT with no LCT remaining in the diet, no steatosis developed and hepatic TNF-alpha was low. When all MCT were given with carbohydrates (instead of LCT) hepatic TNF-alpha also decreased (p<0.001). CONCLUSIONS: MCT are not hepatotoxic, provided the diet contains no significant amount of LCT. Total replacement of dietary LCT with MCT fed ad libitum is beneficial whereas partial replacement becomes hepatotoxic, unless the dietary intake is restricted. 相似文献
87.
Lee DS Goodman S Dean DM Lenis J Ma P Gervais PB Langer A;PRIDE Investigators 《American heart journal》2002,144(1):60-67
88.
Manoela B Braga Anatoly Langer Lawrence A Leiter 《Experimental & Clinical Cardiology》2008,13(2):71-74
Overwhelming evidence supports a causal relationship between elevated levels of plasma cholesterol, particularly low-density lipoprotein cholesterol, and increased risk of coronary artery disease, which remains the leading cause of death and morbidity worldwide. Low-density lipoprotein cholesterol lowering has been the main goal of therapy, and clinical trial results from recently published studies of intensive statin therapy confirm the benefits of more aggressive lipid-lowering targets, particularly in subjects at high risk for cardiovascular events. This management update will focus on the implications of risk reduction in patients at high cardiovascular risk, and will provide practical steps to help further risk stratify these patients and help them reach their target goals. 相似文献
89.
90.
Turton JP Mehta A Raza J Woods KS Tiulpakov A Cassar J Chong K Thomas PQ Eunice M Ammini AC Bouloux PM Starzyk J Hindmarsh PC Dattani MT 《Clinical endocrinology》2005,63(1):10-18
OBJECTIVE: Mutations within the pituitary-specific paired-like homeobox gene PROP1 have been described in 50-100% of patients with familial combined pituitary hormone deficiency (CPHD). We screened a cohort of sporadic (n = 189) and familial (n = 44) patients with hypopituitarism (153 CPHD and 80 isolated hormone deficiencies) for mutations within the coding sequence of PROP1. DESIGN AND PATIENTS: Patients with congenital hypopituitarism were recruited from the London Centre for Paediatric Endocrinology as well as several national and international centres. The pituitary phenotype ranged from isolated growth hormone deficiency (IGHD) to panhypopituitarism. Clinical data, including endocrine and neuro-radiological studies were obtained from patient records, and DNA was collected and screened for mutations within PROP1 using PCR and single-stranded conformation polymorphism (SSCP) analysis. Positive results on SSCP were sequenced directly. RESULTS: The prevalence of PROP1 mutations in unselected sporadic cases of hypopituitarism was lower (1.1%) than in familial cases (29.5%). PROP1 mutations can be associated with a highly variable phenotype, and both pituitary hypoplasia and pituitary hyperplasia. We describe the waxing and waning of a pituitary mass over 20 months in association with a PROP1 mutation that is predicted to lead to complete loss of function. Additionally, we have identified a possible founder mutation in CPHD patients from the Indian subcontinent. CONCLUSIONS: PROP1 mutations are rare in sporadic cases of CPHD, although the prevalence rises if there is a positive family history or if the patients are carefully selected with respect to the endocrine and neuroradiological phenotype. There is considerable phenotypic variability in families with the same mutation, indicating the role of other genetic or environmental factors on phenotypic expression. Finally, the pituitary enlargement that is observed in patients with PROP1 mutations can wax and wane in size before eventual involution. 相似文献