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71.
M B Casey E Winner I Hurwitz D DaSilva 《Journal of clinical and experimental neuropsychology》1991,13(4):600-606
This study investigated the effects of visual vs. verbal processing style preferences on immediate recall accuracy for the Rey-Osterrieth and Taylor Complex Figure Tests. Undergraduates were classified as visualizers or verbalizers and asked to copy either the Rey-Osterrieth or Taylor figure and then draw it from memory. A subset of subjects reported the strategy they used to reproduce the figure. Visualizers showed better reproduction accuracy than verbalizers for the Rey-Osterrieth test, and for this test approximately 80% of verbalizers as well as visualizers reported using a visual strategy. For the Taylor, no effect of processing style was obtained, and close to half of the verbalizers (43%) reported using their preferred verbal strategy, while 82% of the visualizers used a visual strategy. These results suggest that a general preference for thinking "in images" is important for predicting visual memory accuracy only on tests such as the Rey-Osterrieth which do not lend themselves easily to a verbal strategy. In contrast, for the Taylor test, deficits to the visual imagery system may be circumvented and obscured by the verbalizers' use of verbal recall strategies. Thus, in test batteries, the Rey-Osterrieth and the Taylor Tests should not be used interchangeably. 相似文献
72.
Data compiled over seven years present evidence that small-group or "cluster" carrels are successfully utilized by medical students in a learning resource center (LRC) and, therefore, should be considered to be an efficient method of managing space, software, and hardware. Three management concepts account for high utilization of an LRC operated as a service in support of a medical school curriculum. Of special importance is the interaction of LRC staff with faculty, which directly accounts for a collection relevant to the curriculum. The other management concepts are responsiveness to students and delivery of services that support production and distribution of print and audiovisual resources for student learning. 相似文献
73.
Primo N Lara Paul Frankel Philip C Mack Paul H Gumerlock Irina Galvin Cynthia L Martel Jeff Longmate James H Doroshow Heinz Josef Lenz Derick H M Lau David R Gandara 《Clinical cancer research》2003,9(12):4356-4362
PURPOSE: Tumor hypoxia confers chemotherapy resistance. Tirapazamine is a cytotoxin that selectively targets hypoxic cells and has supra-additive toxicity with platinums and taxanes in preclinical studies. We conducted a Phase I study of tirapazamine, carboplatin, and paclitaxel and assessed potential plasma markers of hypoxia as surrogates for response. EXPERIMENTAL DESIGN: Forty-two patients with advanced solid tumors were treated at four dose levels; parallel dose escalations were carried out in chemotherapy-naive and previously treated subjects. Pre and post-therapy plasma levels of the hypoxia-induced proteins plasminogen activator inhibitor-1 and vascular endothelial growth factor were measured. RESULTS: Three of four chemotherapy-na?ve patients developed dose-limiting toxicities at dose level 4 (grade 3 stomatitis/infection, grade 3 emesis, and grade 4 febrile neutropenia). Four of seven previously treated patients developed dose-limiting toxicities at dose level 3, including one death [grade 3 myalgia, grade 3 infection/grade 4 neutropenia, grade 3 infection/grade 4 neutropenia, and grade 5 infection (death)/grade 4 neutropenia]. Of 38 patients assessable for response, 3 had a complete response, 1 a partial response, 1 an unconfirmed partial response, and 23 had stable disease in at least one evaluation; 10 quickly progressed. One complete responder had normalization of vascular endothelial growth factor and plasminogen activator inhibitor-1 levels. CONCLUSION: Dose levels 3 (carboplatin AUC of 6, 225 mg/m(2) paclitaxel, and 330 mg/m(2) tirapazamine) and 2 (carboplatin AUC 6, 225 mg/m(2) paclitaxel, and 260 mg/m(2) tirapazamine) are the maximum tolerated doses for chemotherapy naive and patients treated previously, respectively. Dose level 3 is the experimental arm of a Phase III Southwest Oncology Group trial (S0003) in advanced non-small cell lung cancer. Potential markers of tumor hypoxia may be useful correlates in studies of hypoxic cytotoxins and are being prospectively investigated in S0003. 相似文献
74.
Marilyn A Roubidoux Judith Salmon Kaur Kent A Griffith Barbara Stillwater Paul Novotny Jeff Sloan 《Cancer epidemiology, biomarkers & prevention》2003,12(10):1081-1086
The purpose is to determine breast cancer risk factors and correlates of mammographic parenchymal patterns among Alaska Native women. A retrospective review was performed of mammograms and mammogram records among 528 sequential screening mammogram examinations performed in Anchorage, Alaska. Mammogram density was classified by American College of Radiology (Breast Imaging Reporting and Data System) density patterns 1-4 (fat-->dense) and by percent density. Clinical data, including risk factors, ethnic group (Indian, Aleut, or Eskimo), and smoking status were obtained. Results were analyzed by univariate and multivariate analyses. Of 528 women, 164 were Indian, 155 were Aleut, and 209 were Eskimo. Mean age at first birth was lower and parity higher compared with published data in white women. Breast cancer risk factors were similar across ethnic groups. In multivariate analysis, patient age, parity, hormone replacement therapy, hysterectomy, and history of biopsy were associated, and smoking was not associated with density scores. Aleut and Indian women were less likely to have high-density mammograms than were Eskimo women (P = 0.0448). No significant differences were found between ethnic group for conventional breast cancer risk factors. Mammogram density was associated with age at screening, parity, hormone replacement therapy, hysterectomy, history of biopsy, and ethnicity but not smoking status. Eskimo women had higher mammogram density than Aleuts or Indians. 相似文献
75.
Ranjan K. Sur Bernard Donde Victor Levin Juan Pacella Jeff Kotzen Kum Cooper Martin Hale 《The Laryngoscope》1997,107(9):1276-1280
A retrospective analysis was performed of 50 patients with adenoid cystic carcinoma who were seen in the Department of Radiation Oncology, University of Witwatersrand, Johannesburg, South Africa, in the past 10 years. There were 25 men and 25 women with a mean age of 52 years (age range, 21 to 88 years). Five patients had metastatic disease, and 17 had neural invasion. Thirty-four patients had surgery (11, complete; 23, microscopic residual). Sixteen patients had radiotherapy as initial management. The disease-free survival was 26%, overall survival was 29%, and local control was 30% at 10 years. Most recurrences occurred in the first 3 years. Nine patients had metastasis following treatment. The mean survival after metastasis was 15 months. Seven prognostic variables were analyzed using the log-rank test. There was no impact of age, site, type of salivary gland (major vs. minor), tumor stage, node positivity, or neural invasion on disease-free survival, overall survival, or local control. Extent of surgical resection (complete vs. microscopic residual) had a significant impact on disease-free survival and local control (P < 0.05) but no impact on overall survival (P > 0.05) because of the slow-growing nature of these tumors. Similarly, patients who had microscopic residual after surgery and were treated with radiotherapy did better than those who had biopsy and radiotherapy, although this was not significant statistically (P > 0.05). Thus, whenever possible, every attempt must be made to remove all microscopic tumor by surgery. Addition of postoperative radiotherapy with high-energy photons did not improve the locoregional control or survival in our series. There is a place for neutrons in the treatment of adenoid cystic carcinomas in advanced cases of inoperable or recurrent tumors, as a review of literature shows. 相似文献
76.
Impact of education for physicians on patient outcomes 总被引:4,自引:0,他引:4
NM Clark M Gong MA Schork D Evans D Roloff M Hurwitz L Maiman RB Mellins 《Pediatrics》1998,101(5):831-836
77.
Janet Li Paul Roche Jenean Spencer Ivan Bastian Amanda Christensen Mark Hurwitz Anastasios Konstantinos Vicki Krause Moira McKinnon Avner Misrachi Graham Tallis Justin Waring 《Communicable diseases intelligence》2004,28(4):464-473
The National Notifiable Disease Surveillance System (NNDSS) received 982 tuberculosis (TB) notifications in 2003, of which 947 were new cases, 33 were relapses and two were cases with unknown history. The incidence of TB in Australia has remained at a stable rate since 1985 and was 4.9 cases per 100,000 population in 2003. The high-incidence groups remain people born overseas and Indigenous Australians at 19.9 and 8.7 cases per 100,000 population, respectively. By contrast the incidence in non-Indigenous Australians was 0.9 per 100,000. Comparison of the 2003 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups. 相似文献
78.
Using Vignettes to Compare the Quality of Clinical Care Variation in Economically Divergent Countries 下载免费PDF全文
John W. Peabody Fimka Tozija Jorge A. Muñoz Robert J. Nordyke Jeff Luck 《Health services research》2004,39(6P2):1951-1970
Objective. To determine whether clinical vignettes can measure variations in the quality of clinical care in two economically divergent countries.
Data Source/Study Setting. Primary data collected between February 1997 and February 1998 at two Veterans Affairs facilities in the United States and four government-run outpatient facilities in Macedonia.
Study Design. Randomly selected, eligible Macedonian and U.S. physicians (>97 percent participation rate) completed vignettes for four common outpatient conditions. Responses were judged against a master list of explicit quality criteria and scored as percent correct.
Data Collection/ Extraction. An ANOVA model and two-tailed t-tests were used to compare overall scores by case, study site, and country.
Principal Findings. The mean score for U.S. physicians was 67 percent (+/−11 percent) compared to 48 percent (+/−11 percent) for Macedonian physicians. The quality of clinical practice, which emphasizes basic skills, varied greatly in both sites, but more so in Macedonia. However, the top Macedonian physicians in all sites approached or—in one case—exceeded the median score in the U.S. sites.
Conclusions. Vignettes are a useful method for making cross-national comparisons of the quality of care provided in very different settings. The vignette measurements revealed that some physicians in Macedonia performed at a standard comparable to that of their counterparts in the United States, despite the disparity of the two health systems. We infer that in poorer countries, policy that promotes improvements in the quality of clinical practice—not just structural inputs—could lead to rapid improvements in health. 相似文献
Data Source/Study Setting. Primary data collected between February 1997 and February 1998 at two Veterans Affairs facilities in the United States and four government-run outpatient facilities in Macedonia.
Study Design. Randomly selected, eligible Macedonian and U.S. physicians (>97 percent participation rate) completed vignettes for four common outpatient conditions. Responses were judged against a master list of explicit quality criteria and scored as percent correct.
Data Collection/ Extraction. An ANOVA model and two-tailed t-tests were used to compare overall scores by case, study site, and country.
Principal Findings. The mean score for U.S. physicians was 67 percent (+/−11 percent) compared to 48 percent (+/−11 percent) for Macedonian physicians. The quality of clinical practice, which emphasizes basic skills, varied greatly in both sites, but more so in Macedonia. However, the top Macedonian physicians in all sites approached or—in one case—exceeded the median score in the U.S. sites.
Conclusions. Vignettes are a useful method for making cross-national comparisons of the quality of care provided in very different settings. The vignette measurements revealed that some physicians in Macedonia performed at a standard comparable to that of their counterparts in the United States, despite the disparity of the two health systems. We infer that in poorer countries, policy that promotes improvements in the quality of clinical practice—not just structural inputs—could lead to rapid improvements in health. 相似文献
79.
Phase I trial of 17-allylamino-17-demethoxygeldanamycin in patients with advanced cancer. 总被引:13,自引:0,他引:13
Matthew P Goetz David Toft Joel Reid Matthew Ames Bridget Stensgard Stephanie Safgren Araba A Adjei Jeff Sloan Pamela Atherton Vlad Vasile Sandra Salazaar Alex Adjei Gary Croghan Charles Erlichman 《Journal of clinical oncology》2005,23(6):1078-1087
PURPOSE: We determined the maximum-tolerated dose (MTD) and the dose-limiting toxicities (DLT) of 17-allylamino-17-demethoxygeldanamycin (17-AAG) when infused on days 1, 8, and 15 of a 28-day cycle in advanced solid tumor patients. We also characterized the pharmacokinetics of 17-AAG, its effect on chaperone and client proteins, and whether cytochrome P450 (CYP) 3A5 and NAD(P)H:quinone oxidoreductase 1 (NQO1) polymorphisms affected 17-AAG disposition or toxicity. PATIENTS AND METHODS: An accelerated titration design was used. Biomarkers were measured in peripheral-blood mononuclear cells (PBMCs) at baseline and on days 1 and 15, and pharmacokinetic analysis was performed on day 1 of cycle 1. CYP3A5*3 and NQO1*2 genotypes were determined and correlated with pharmacokinetics and toxicity. RESULTS: Twenty-one patients received 52 courses at 11 dose levels. DLTs at 431 mg/m(2) were grade 3 bilirubin (n = 1), AST (n = 1), anemia (n = 1), nausea (n = 1), vomiting (n = 1), and myalgias (n = 1). No tumor responses were seen. 17-AAG consistently increased heat shock protein (Hsp) 70 levels in PBMCs. At the MTD, the clearance and half-life (t(1/2)) of 17-AAG were 11.6 L/h/m(2) and 4.15 hours, respectively; whereas the active metabolite 17-aminogeldanamycin had a t(1/2) of 7.63 hours. The CYP3A5*3 and NQO1*2 polymorphisms were not associated with 17-AAG toxicity. The CYP3A5*3 polymorphism was associated with higher 17-AAG clearance. CONCLUSION: The MTD of weekly 17-AAG is 308 mg/m(2). 17-AAG induced Hsp70 in PBMCs, indicating that Hsp90 has been affected. Further evaluation of 17-AAG is ongoing using a twice-weekly regimen, and this schedule of 17-AAG is being tested in combination with chemotherapy. 相似文献
80.
Clinical evaluation of ZD6474, an orally active inhibitor of VEGF and EGF receptor signaling, in patients with solid, malignant tumors. 总被引:7,自引:0,他引:7
S N Holden S G Eckhardt R Basser R de Boer D Rischin M Green M A Rosenthal C Wheeler A Barge H I Hurwitz 《Annals of oncology》2005,16(8):1391-1397
BACKGROUND: ZD6474 selectively inhibits the tyrosine kinase activity of vascular endothelial growth factor receptor and epidermal growth factor receptor. The safety, tolerability and pharmacokinetics of ZD6474 were assessed in a phase I dose-escalation study of patients with advanced solid tumors. PATIENTS AND METHODS: Adult patients with tumors refractory to standard treatments received once-daily oral ZD6474 (50-600 mg) in 28-day cycles, until disease progression or unacceptable toxicity was observed. RESULTS: Seventy-seven patients were treated at doses of 50 mg (n=9), 100 mg (n=19), 200 mg (n=8), 300 mg (n=25), 500 mg (n=8), and 600 mg (n=8). Adverse events were generally mild, and the most common dose-limiting toxicities (DLT) were diarrhea (n=4), hypertension (n=4), and rash (n=3). The incidence of most adverse events appeared to be dose-dependant. In the 500 mg/day cohort, 3/8 patients experienced DLT and this dose was therefore considered to exceed the maximum tolerated dose. Pharmacokinetic analysis confirmed that ZD6474 was suitable for once-daily oral dosing. CONCLUSIONS: Once-daily oral dosing of ZD6474 at 300 mg/day is generally well tolerated in patients with advanced solid tumors, and this dose is being investigated in phase II trials. 相似文献