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Seung‐Cheol Lee Harish Poptani Stephen Pickup W. Timothy Jenkins Sungheon Kim Cameron J. Koch E. James Delikatny Jerry D. Glickson 《NMR in biomedicine》2010,23(6):624-632
The purpose of the study was to investigate the capability of 1H MRS and MRI methods for detecting early response to radiation therapy in non‐Hodgkin's lymphoma (NHL). Studies were performed on the WSU‐DLCL2 xenograft model in nude mice of human diffuse large B‐cell lymphoma, the most common form of NHL. Radiation treatment was applied as a single 15 Gy dose to the tumor. Tumor lactate, lipids, total choline, T2 and apparent diffusion coefficients (ADC) were measured before treatment and at 24 h and 72 h after radiation. A Hadamard‐encoded slice‐selective multiple quantum coherence spectroscopy sequence was used for detecting lactate (Lac) while a stimulated echo acquisition mode sequence was used for detection of total choline (tCho) and lipids. T2‐ and diffusion‐weighted imaging sequences were used for measuring T2 and ADC. Within 24 h after radiation, significant changes were observed in the normalized integrated resonance intensities of Lac and the methylenes of lipids. Lac/H2O decreased by 38 ± 15% (p = 0.03), and lipid (1.3 ppm, CH2)/H2O increased by 57 ± 14% (p = 0.01). At 72 h after radiation, tCho/H2O decreased by 45 ± 14% (p = 0.01), and lipid (2.8 ppm, polyunsaturated fatty acid)/H2O increased by 970 ± 36% (p = 0.001). ADC increased by 14 ± 2% (p = 0.003), and T2 did not change significantly. Tumor growth delay and regression were observed thereafter. This study enabled comparison of the relative sensitivities of various 1H MRS and MRI indices to radiation and suggests that 1H MRS/MRI measurements detect early responses to radiation that precede tumor volume changes. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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AIDS Knowledge, Attitudes, and Behavior Among Inner City, Junior High School Students 总被引:3,自引:0,他引:3
David Siegel MD MPH Flora Krasnovsky MA Meg Durbin MD Margaret Chesney PhD Nancy Lazarus MD MPH 《The Journal of school health》1991,61(4):160-165
To gain information about AIDS knowledge, attitudes, and behavior of junior high school students, 1,967 students in three junior high schools in an inner city school district were surveyed. Ages of the participants ranged from 11-16 years, and 48% were male. Ethnically, 33% were Asian, 31% African-American, 24% Latino, and 5% white. African-American students had greater AIDS general knowledge than Asians and similar general knowledge to Latinos and whites. Most students wanted to be taught about AIDS in school. Misconceptions about casual contagion of AIDS were common. Students with these misconceptions were more likely to believe that students with AIDS should not be allowed to attend school. A high proportion of students had engaged in high-risk behavior including sexual intercourse, drinking alcoholic beverages, and using street drugs. More boys than girls reported each of these activities. Of individuals having had sexual intercourse, a positive association was found between the belief that condoms are effective in preventing HIV infection and use of condoms. These findings support the possibility that improving knowledge about HIV transmission would result in more tolerance toward students with HIV infection and would result in less high-risk behavior. 相似文献
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Evaluation of nuclear matrix protein 22 as a tumour marker in the detection of transitional cell carcinoma of the bladder. 总被引:11,自引:0,他引:11
OBJECTIVES: To evaluate the sensitivity and specificity of urinary nuclear matrix protein-22 (NMP22) in detecting bladder cancer, to compare the diagnostic performance of NMP22 alone and when corrected by urinary creatinine level, and to correlate NMP22 level with the histological and clinical characteristics of bladder cancer. PATIENTS, SUBJECTS AND METHODS: The study included 267 patients classified into five groups: group 1 comprised 111 patients with active transitional cell carcinoma (TCC) of the bladder; group 2 included 76 patients who had had bladder TCC but were being followed and were free of disease, as confirmed by cystoscopy; group 3 comprised 25 patients with benign urological diseases; group 4 included 25 patients with other malignant pathological conditions; group 5 constituted a control group of 30 healthy subjects free of urological diseases. Urinary NMP22 was measured using an enzyme-linked immunosorbent assay. Receiver operating characteristic (ROC) curves were constructed to obtain the thresholds which gave optimal sensitivity and specificity for combinations of NMP22 alone and when corrected by urinary creatinine level. Stage, grade, tumour size, pattern of growth, focality and the presence of recurrence were recorded and their associations with NMP22 evaluated. RESULTS: The mean levels of NMP22 were 122.8, 5.1, 3.7, 2.3 and 0.3 U/mL for groups 1-5, respectively; overall, these values were significantly different (P<0.001). The mean (95% CI) optimal combination of 78.2% (69.3-85.5) sensitivity and 95.5% (87.3-99.0) specificity was obtained from the ROC analysis with a threshold value of 13.7 U/mL NMP22. When values were corrected by urinary creatinine levels, the threshold given by the best combination of sensitivity and specificity, at 73.2% (63.2-81.7) and 97.0% (89.6-99.5), respectively, was 3.0 U/mg creatinine. NMP22 level was statistically associated with stage, grade, tumour size and focality. CONCLUSIONS: Urinary NMP22 appeared to be a potential tumour marker for detecting TCC of the bladder; when corrected by urinary creatinine level, it might provide a better interpretation than when used alone. NMP22 correlated with the most relevant variables in bladder cancer. As a noninvasive adjunct, NMP22 might have a role in guiding urologists about the need for cystoscopy in such patients. 相似文献
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