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Paul R Helft Rachael E Eckles Cynthia Stair Johnson-Calley Christopher K Daugherty 《Journal of clinical oncology》2005,23(22):4954-4962
PURPOSE: To evaluate rates, predictors, and barriers to use of the Internet to obtain cancer information among a cohort of cancer patients at an urban county hospital. PATIENTS AND METHODS: Of 208 cancer patients approached, 200 patients completed a structured interview study examining Internet use, perceptions of the accuracy of Internet information, and barriers to use. RESULTS: Only 10% of participants reported using the Internet themselves to obtain cancer information. Another 21% reported exposure to Internet information through proxies. The most common barrier to Internet use cited was lack of Internet access, with 44% reporting that they would use the Internet to obtain cancer information if they had Internet access. Younger age and more years of formal education were significantly associated with Internet use, although race and income were not. Less education, African American race, and female sex were associated with lower estimates of the accuracy of Internet information. Fewer years of formal education was associated with increased likelihood of reporting confusion after reading Internet information. CONCLUSION: Very few cancer patients in this study of a cohort of generally disadvantaged individuals used the Internet themselves to obtain cancer information, although many more desired to do so. Significant opportunities for Web-based interventions aimed at improving cancer care outcomes in this population of cancer patients exist. However, further study will be needed to determine how to make such intervention accessible, trustworthy, and understandable to the disadvantaged. 相似文献
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Donald B. White Cynthia A. Walawander Dong Y. Liu Thaddeus H. Grasela 《Journal of pharmacokinetics and pharmacodynamics》1992,20(3):295-313
In a simulation study of inference on population pharmacokinetic parameters, two methods of performing tests of hypotheses comparing two populations using NONMEM were evaluated. These two methods are the test based upon 95% confidence intervals and the likelihood ratio test. Data were simulated according to a monoexponential model and, in that context, power curves for each test were generated for (i)the ratio of mean clearance and (ii)the ratio of the population standard deviations of clearance. To generate the power curves, a range of these parameters was employed; other pharmacokinetic parameters were selected to reflect the variability typically present in a Phase II clinical trial. For tests comparing the means, the confidence interval tests had approximately the same power as the likelihood ratio tests and were consistently more faithful to the nominal level of significance. For comparison of the standard deviations, and when the volume of information available was relatively small, however, the likelihood ratio test was more able to detect differences between the two groups. These results were then compared to results on parameter estimation in order to gain insight into the question of power. As an example, the nonnormality of estimates of the ratio of standard deviations plays an important role in explaining the low power for the confidence interval tests. We conclude that, except for the situation of modeling standard deviations with only sparse information, NONMEM produces tests of significance that are effective at detecting clinically significant differences between two populations.Partial support from the Upjohn Company, NIH-BRSG SO RR 07066, and the Burroughs Wellcome Foundation. 相似文献
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Malignant glioma is a devastating disease which presents a clinical challenge to physicians and neuroscience nurses. It carries a dismal prognosis, with a median survival of only nine months following application of conventional therapies of surgical resection, radiotherapy and chemotherapy. Hyperthermia is the application of sufficient heat to raise the temperature in a volume of tumor to cytocidal levels. Patient tolerance and response to volumetric interstitial hyperthermia treatment in this clinical study of over 40 patients has been extremely encouraging. Hyperthermia, as part of multi-modality treatment of brain tumors, presents a change in the nursing management of this patient population. The neuroscience nurse plays a crucial role in linking clinical observations to decisions of patient management and treatment planning. Because hyperthermia is a new treatment modality, nurses, patients and families require additional education and extended support during therapy. 相似文献
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J A Thorp G R Cohen J D Yeast D Perryman C Welsh N Honssinger S Stephenson J Hedrick 《American journal of perinatology》1992,9(1):22-24
Fetal hydrops at 26 weeks' gestation was diagnosed following a massive fetomaternal hemorrhage. Fetal intravascular transfusion was performed, and the hydrops completely resolved within 72 hours. The fetus required one more transfusion at 27 weeks' gestation. A subsequent percutaneous umbilical blood sampling at 30 weeks' gestation demonstrated a normal fetal hematocrit. A vaginal delivery at term resulted in a normal newborn. Massive fetomaternal hemorrhage is a well-known cause of nonimmune hydrops and may occur spontaneously in an otherwise normal pregnancy. Confirmation by percutaneous umbilical blood sampling and treatment by intravascular transfusion is recommended when massive fetomaternal hemorrhage causes hydrops in preterm gestations. 相似文献
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OBJECTIVE: The purpose of this study was to determine the efficacy and safety of a targeted narrow band UVB/UVA1 therapy for the treatment of striae alba. METHODS: Fourteen individuals with skin types II-VI were enrolled in this 22-week trial that consisted of up to 10 treatments with a combination of UVB/UVA1 (MultiClear, Curelight Ltd, Israel). Participants were treated with a maximum of 10 treatments unless 100% repigmentation of stretch was achieved prior to the tenth treatment. Biopsies were taken from willing participants at baseline, immediately after the final treatment and 12 weeks after the last treatment. RESULTS: Nine participants completed all treatment visits. After the final treatment, all the participants had >51% repigmentation of the treated striae. At the 4-week follow-up visit, 67% of participants had greater than 51% improvement, and 56% had greater than 51% improvement at the 8-week and 12-week follow-ups. Hyperpigmentation of striae was seen in >50% of the participants treated. The pretreatment biopsies were confirmatory of striae. There were no diagnostic light microscopic differences in the 4-week post-treatment biopsy set available in one patient. CONCLUSION: This high intensity UVB\UVA1 device is an effective and safe modality for the short-term repigmentation of hypopigmented stretch marks. Additional morphologic studies over time are needed to confirm these clinical findings. 相似文献