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61.
62.
q-Space diffusion of myelin-deficient spinal cords. 总被引:1,自引:0,他引:1
The apparent water diffusion anisotropy in white matter (WM) of excised spinal cords of myelin-deficient (md) rats and their age-matched controls was studied by high-b-value q-space diffusion MRS and MRI at different diffusion times. Non-monoexponential signal decay was observed at long diffusion times. The mean displacements in the md spinal cords were found to be higher than those of the controls. The apparent anisotropy (AA) of the fast-diffusing component was found to decrease more dramatically with the increase in diffusion time for the md spinal cords as compared with controls, whereas the AA of the slow-diffusing component in the controls was found to increase with the increase in diffusion time while that of the md cords decreased with the increase in diffusion time. When diffusion MRI was performed, similar diffusion anisotropy was extracted for the md and control spinal cords at diffusion times of 22 and 50 ms. Only at a diffusion time of about 200 ms was a significant difference obtained in the AA of the two groups. This originates from the much smaller increase in the mean displacement perpendicular to the fiber direction in the control group vs. the md group when the diffusion time was increased. 相似文献
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OBJECTIVE: There are currently no studies that have investigated dietary supplement use in the chronic renal insufficiency (CRI) population. The objectives of this study were to determine the prevalence of dietary supplement use in a sample of adults with CRI and to examine whether the prevalence of dietary supplement use was higher in the earlier stages of CRI. DESIGN AND SETTING: Cross-sectional survey conducted at an outpatient nephrology clinic. PATIENTS: Adults (n = 100) with varying degrees of CRI. INTERVENTION: Interview-administered questionnaire. MAIN OUTCOME MEASURES: The questionnaire contained questions related to the use of dietary supplements, attitudes, and beliefs about dietary supplements, as well as medical and demographic data including gender, age, body weight, smoking status, concurrent chronic conditions, prescribed medications, serum creatinine, estimated glomerular filtration rate (GFR), etiology of CRI, income, and education level. RESULTS: The prevalence of dietary supplement use was 45%, with the most frequent use occurring in subjects with a mild to moderate degree of renal insufficiency. There were no significant differences in gender, age, body mass index, smoking status, number of concurrent chronic conditions, number of prescribed medications, income, or education level between supplement users and supplement nonusers. Further analysis of dietary supplement use showed that the number of supplements used ranged from 1 to 5 or more supplements per day, with an overall total of 36 different supplements. Dietary supplement users were significantly more concerned with their health than were supplement nonusers. The most frequent sources of supplement information were physicians and printed material; however, 75% of the dietary supplement users desired further information about their dietary supplements. CONCLUSION: This is the first study to investigate the use of dietary supplements in adults with CRI, and it provides valuable information for health care professionals regarding the dietary supplement use of their patients with CRI. 相似文献
65.
KLEPP K-I.; ULVIK R.J.; MATTHIESEN S.B.; HANNAN P.; JACOBS D.R. JR.; AARO L.E. 《European journal of public health》1993,3(1):38-42
The general public of the City of Bergen, Norway was Invitedto participate in a cholesterol screening programme in October1988. Participants received the results of the cholesterol screeningand nutritional information from trained health personnel. Ashort questionnaire was mailed to all 354 participants 12weeks after the initial cholesterol screening. In March 1990,all participants were invited to have their cholesterol levelsre-examined. Psychosocial factors believed to be predictiveof future serum cholesterol changes were assessed at baselinealong with demographic variables. The majority of participants(61%) reduced their cholesterol level from October 1988 to March1990, and the average reduction in cholesterol level for thetotal population was 4.0%. Baseline cholesterol levels, beingconfident of one's own ability to change one's diet (self-efficacy),seeing heart disease risk reduction as very important, and maritalstatus were factors that significantly predicted successfulcholesterol reduction 18 months later. 相似文献
66.
Postoperative radiation therapy in the management of lung cancer 总被引:1,自引:0,他引:1
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate. 相似文献
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J Lloyd Michener Mary T Champagne Duncan Yaggy Susan D Yaggy Katrina M Krause 《Academic medicine》2005,80(1):57-61
Academic medical centers (AMCs) have traditionally provided primary care for low-income and other underserved populations. However, they have had difficulty developing lasting partnerships with other organizations serving the same populations. This article describes an exception to the rule, in which an academic division was created at Duke University Medical Center to develop effective collaborations with health care and social service providers in Durham, North Carolina, including both public agencies and private organizations. Together, the division and its partners have created and operate programs that improve health outcomes and access to care for those at risk. These programs share a number of characteristics: they are designed to meet the needs of the patient, not the provider; they are based in the community, not in the AMC; they bring services to people's homes, schools, and neighborhoods; they are multidisciplinary, combining health, social, and even mental health services; and, once established, they are revenue-generating and can be made self-supporting when grant funding ends. These programs are also innovative. They are designed to model and test new ways of organizing and delivering care. Preliminary indications suggest that they also strengthen the AMC's relationships with the surrounding community. 相似文献
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Urinary cytokines following photodynamic therapy for bladder cancer. A preliminary report 总被引:1,自引:0,他引:1
This preliminary study was undertaken to test for the presence of urinary cytokines whose detection would provide evidence in support of the theory that photodynamic therapy (PDT) produces an immunologic response in patients treated for bladder cancer. Gamma interferon, interleukin 1-beta, interleukin 2, and tumor necrosis factor-alpha were assayed for in the urine of 4 patients treated with photodynamic therapy for bladder cancer, in 7 control patients undergoing transurethral surgical procedures, and in 5 healthy control subjects. Quantifiable concentrations of all cytokines, except gamma interferon, were measured in urine samples from the PDT patients with the highest light energies, while no urinary cytokines were found in the PDT patient who received the lowest light energy nor in any of the control subjects. These findings suggest that a local immunologic response may occur following PDT for bladder cancer. 相似文献