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排序方式: 共有2032条查询结果,搜索用时 15 毫秒
1.
Judith Bernardini Valerie Price Ana Figueiredo Aase Riemann Dora Leung 《Peritoneal dialysis international》2006,26(6):658-663
OBJECTIVE: To survey nurses around the world about current practices for peritoneal dialysis (PD) home training programs. DESIGN: Random sampling of nurses to complete a written survey from the International Society for Peritoneal Dialysis Nursing Liaison Committee. Settings: United States, Canada, South America (Brazil, Columbia), The Netherlands, Hong Kong. METHODS: Surveys and responses were sent by fax whenever possible, or by regular mail, or hand carried, or conducted by telephone. Results were stratified by geographic areas as well as by cumulative responses and were expressed as medians with ranges. Kruskal-Wallis was used to evaluate differences in responses. Associations between variables were tested with Pearson correlation. Univariate regression analysis was used to evaluate the impact of variables on peritonitis rates. Variables with p < 0.10 were included in a multivariate analysis. RESULTS: A total of 317 nurses responded: 88 in the United States, 46 in Canada, 58 in South America, 58 in Hong Kong, and 67 in The Netherlands. This represented 37% of all surveys distributed. Respondents had a median of 12 years' experience in nephrology (range 1-35 years), but only 31% had a formal background in adult education. Nearly half received their guidance to patient training from a nurse colleague, 11% were guided by a corporate colleague, and 8% were simply self-taught. Clinics responding had a median of 30 PD patients (range 1-400) and reported they trained a median of 8 patients per year (range 0-86). Reported peritonitis rates were a median 0.46 per year or 1 episode every 26 months. Peritonitis rates, however, were not known by 53% of respondents. Total training time per patient had a very wide range of hours, from 6 to 96. There was no correlation between training time and peritonitis rates among the study respondents (p = 0.38), nor with any other variables. CONCLUSIONS: There is wide variation in practices for PD patient training programs within countries and around the world. Training time did not appear to be related to peritonitis rates. Randomized trials of training practices are needed to determine which approaches produce the best outcomes for patients. 相似文献
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John Goffin Stefan Baral Dongsheng Tu Dora Nomikos Lesley Seymour 《Clinical cancer research》2005,11(16):5928-5934
PURPOSE: Tumor responses in early-phase trials are used to determine whether new agents warrant further study. Given that spontaneous regressions are observed in melanoma and renal cell carcinoma, this study assessed whether tumor responses, particularly in these two tumor types, predict for future regulatory drug approval. EXPERIMENTAL DESIGN: The literature was reviewed to assess tumor response rates to cytotoxic agents in phase I and II trials in the following solid tumors: melanoma, renal cell carcinoma, non-small-cell lung cancer, breast cancer, ovarian cancer, colorectal cancer, and other solid tumors. Response rates were categorized and the relationship of these categories to the end point of regulatory drug approval was determined. RESULTS: Fifty-eight drugs were assessed in 100 phase I trials, and 46 of these drugs were also studied in 499 phase II trials. Higher overall response rates in both phase I trials (P = 0.03) and phase II trials (P < 0.0001) were predictive of regulatory approval. However, response in melanoma or renal cell carcinoma was not predictive for either phase I or phase II studies. CONCLUSIONS: For cytotoxic agents, although overall objective response rates reliably predict subsequent marketing approval, isolated responses in melanoma and renal cell carcinoma are not predictive. 相似文献
5.
Circulating levels of inflammatory markers and cancer risk in the health aging and body composition cohort. 总被引:8,自引:0,他引:8
Dora Il'yasova Lisa H Colbert Tamara B Harris Anne B Newman Douglas C Bauer Suzanne Satterfield Stephen B Kritchevsky 《Cancer epidemiology, biomarkers & prevention》2005,14(10):2413-2418
BACKGROUND: Chronic inflammation is associated with processes that contribute to the onset or progression of cancer. This study examined the relationships between circulating levels of the inflammatory markers interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-alpha) and total as well as site-specific cancer incidence. METHODS: Study subjects (n = 2,438) were older adults (ages 70-79 years) participating in the Health Aging and Body Composition study, who did not report a previous cancer diagnosis (except for nonmelanoma skin cancer) at baseline. Incident cancer events (n = 296) were ascertained during an average follow-up of 5.5 years. Inflammatory markers were measured in stored baseline fasting blood samples. RESULTS: The adjusted hazard ratios (95% confidence intervals) for incident cancer associated with a 1-unit increase on the natural log-scale were 1.13 (0.94-1.37), 1.25 (1.09-1.43), and 1.28 (0.96-1.70) for IL-6, CRP, and TNF-alpha, respectively. Markers were more strongly associated with cancer death: hazard ratios were 1.63 (1.19-2.23) for IL-6, 1.64 (1.20-2.24) for CRP, and 1.82 (1.14-2.92) for TNF-alpha. Although precision was low for site-specific analyses, our results suggest that all three markers were associated with lung cancer, that IL-6 and CRP were associated with colorectal cancer, and that CRP was associated with breast cancer. Prostate cancer was not associated with any of these markers. CONCLUSIONS: These findings suggest that (a) the associations between IL-6, CRP, and TNF-alpha and the risk of cancer may be site specific and (b) increased levels of inflammatory markers are more strongly associated with the risk of cancer death than cancer incidence. 相似文献
6.
Comparison of Benchtop Microplate Beta Counters with the Traditional Gamma Counting Method for Measurement of Chromium-51 Release in Cytotoxic Assays 下载免费PDF全文
Dora Wallace Allan Hildesheim Ligia A. Pinto 《Clinical and Vaccine Immunology : CVI》2004,11(2):255-260
The most traditional method used to measure the lytic activity of cytotoxic T lymphocytes or natural killer (NK) cells is the chromium release assay (CRA). No study has been reported that systematically compares the traditional gamma counting method with various benchtop microplate scintillation formats to measure chromium release. Here we investigated the utilization of microplate beta counters in comparison with the traditional gamma counting method to quantitate antigen-specific cytolysis, lymphokine-activated killer (LAK) activity, and NK activity in the CRA. Supernatants from standard CRA (n = 7) were directly transferred to a 96-well microplate containing either a solid scintillant (Lumaplate) or a liquid scintillant (flexible beta plate). Samples were quantified by using two benchtop microplate beta counters, Wallac Microbeta Trilux (Lumalux and Trilux methods, respectively) and Packard TopCount instruments (TopCount method). These results were then compared with data from an identical assay run in parallel using the traditional gamma counting method (LKB). The lytic activity for influenza virus-stimulated effectors measured in the benchtop microplate beta counters using Lumalux and Trilux methods exhibited excellent correlations with the one measured in the traditional LKB (r = 0.967 and 0.968, respectively). The TopCount method demonstrated a similar correlation (r = 0.966). Similar findings were observed for LAK and NK activity. The 96-well microplate format, specifically the dry-scintillant Lumaplates, offers several advantages over the traditional gamma counting format. Most notable are the reductions in sample volume needed and in the total sample preparation and counting time. Furthermore, this system reduces the amount of dry and mixed radioactive waste generated while using the same instrument for gamma- and beta-emitting isotopes. 相似文献
7.
Genetic variants of homocysteine metabolizing enzymes and the risk of coronary artery disease 总被引:2,自引:0,他引:2
Janosíková B Pavlíková M Kocmanová D Vítová A Veselá K Krupková L Kahleová R Krijt J Kraml P Hyánek J Zvárová J Andel M Kozich V 《Molecular genetics and metabolism》2003,79(3):167-175
It is unresolved whether elevated homocysteine in coronary artery disease (CAD) is the cause of arteriosclerosis or its consequence. In contrast, genetic variants of enzymes that metabolize homocysteine cannot be altered by arteriosclerosis. Consequently, their association with CAD would permit to imply causality. We modeled by regression analysis the effect of 11 variants in the methionine cycle upon CAD manifestation in 591 controls and 278 CAD patients. Among the examined variants only the carriership for the c.844ins68 in the cystathionine beta-synthase (CBS) gene was associated with a significantly lowered risk of CAD (OR=0.56; 95% CI=0.35-0.90 in the univariable, and OR=0.41, 95% CI=0.19-0.89 for obese people in the multivariable analysis, respectively). Healthy carriers of the c.844ins68 variant exhibited, compared to the wild type controls, significantly higher postload ratios of blood S-adenosylmethionine to S-adenosylhomocysteine (61.4 vs. 54.9, p=0.001) and of plasma total cysteine to homocysteine (8.6 vs. 7.3, p=0.004). The changes in these metabolites are compatible with an improved methylation status and with enhanced activity of homocysteine transsulfuration. In conclusion, the coincidence of clinical and biochemical effects of a common c.844ins68 CBS variant supports the hypothesis that compounds relating to homocysteine metabolism may play role in the development and/or progression of CAD. 相似文献
8.
Lena Möbus Elke Rodriguez Inken Harder Agatha Schwarz Ulrike Wehkamp Dora Stölzl Nicole Boraczynski Sascha Gerdes Thomas Litman Andreas Kleinheinz Susanne Abraham Annice Heratizadeh Christiane Handrick Eva Haufe Jochen Schmitt Thomas Werfel Stephan Weidinger 《The Journal of allergy and clinical immunology》2021,147(5):1959-1965.e2
9.
Sleep apnea-related cognitive deficits and intelligence: an implication of cognitive reserve theory 总被引:3,自引:0,他引:3
Alchanatis M Zias N Deligiorgis N Amfilochiou A Dionellis G Orphanidou D 《Journal of sleep research》2005,14(1):69-75
Cognitive deficits in patients with obstructive sleep apnea syndrome (OSAS) are well demonstrated, but the pathophysiology of these deficits is still controversial, as the relationship between OSA severity and cognitive deficits is usually weak. Our study considers the possible relationship between OSA-related cognitive deficits and the overall intellectual function of OSA patients. Forty-seven OSA patients and 36 normal individuals underwent a neuropsychological battery test assessing attention and alertness. According to the resulting IQ score, patients and controls were divided into a high-intelligence group (IQ > or = 90th percentile) and a normal-intelligence group (50 < or = IQ < 90%ile). Between the two patient groups there were no significant differences noticed, regarding OSA severity or sleepiness. High-intelligence patients showed the same attention/alertness performance compared with the high-intelligence controls. On the contrary, patients with normal-intelligence showed attention/alertness decline compared with the normal-intelligence control group. The two patient groups were re-examined with the same battery test after at least 1 year of CPAP treatment. At re-examination neither patient group showed any differences regarding attention and alertness compared with the control groups. We assume that high-intelligence may have a protective effect against OSA-related cognitive decline, perhaps due to increased cognitive reserve. 相似文献
10.
Luis F Gonzalez-Cuyar Dora Lam-Himlin Fabio Tavora Allen Burke Rudy J Castellani 《Cardiovascular pathology》2008,17(2):113-116
BACKGROUND: Bilateral internal carotid artery agenesis (ICAA) is a rare developmental anomaly of unknown etiology that is often associated with disruption of adequate perfusion to the central nervous system. Nevertheless, some patients remain asymptomatic due to collateral circulation involving the communicating arteries of the Circle of Willis. Secondary to the hemodynamical stress through the collateral circulation, affected patients are at an increased risk of developing subarachnoid hemorrhage and intracranial aneurysms. METHODS AND RESULTS: We report an unusual case of a 62-year-old man with bilateral ICAA who expired following two asystolic events during minor surgery. CONCLUSION: This case emphasizes the plasticity of the cerebral collateral circulation during development, to the point of normal cerebral perfusion throughout life with no ischemic complications. 相似文献