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A series of compounds was synthesized, these compounds were tested for Hela-S3cells in vitro for radiosensitizing activity. Five of them are 2,2′- (arylimino)-diethyl-sodium thio-sulfate and two of them are phenylalanine derivatives. Most of them showed various degrees of ra-diosensitizing activity. Among them, SER of L07 was 1.89 at 3 mmol, and had low cytotoxicity toHela-S3 cells;ID50 was 18.8 mmol. The relationship between radiosensitizing effects and chemicalstructure was discussed. It offers a base for further exploration of selectively hypoxic cell radiosens-itizers. 相似文献
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Turner DA; Alcorn FS; Shorey WD; Stelling CB; Mategrano VC; Merten CW; Silver B; Economou SG; Straus AK; Witt TR 《Radiology》1988,168(1):49-58
Detectability of breast cancer with magnetic resonance (MR) imaging versus xeromammography was quantitatively compared. MR images were obtained of breasts of 120 women who underwent xeromammography. T1 values were determined for masses larger than 2 cm. Cancer was histologically confirmed in 39 breasts and was considered excluded from 81 due to results of biopsy, cyst aspiration, or sonography or absence of change in xeromammographic findings over time. Images were blindly interpreted by three observers, and results were expressed as receiver operating characteristic curves. Detectability of breast cancer was substantially better with xeromammography than with MR imaging for all observers (P less than .03, 10(-6), and .001). On MR images, spiculation of a mass, distorted architecture, skin thickening, and nipple or skin retraction were specific but relatively insensitive indicators of cancer. Masses with smooth, distinct margins and signal intensity greater than that of fat on T2-weighted images were always benign. Other findings and T1 values were not diagnostically useful. The authors conclude that xeromammography is superior to MR imaging in detection of breast cancer. 相似文献
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BACKGROUND: To investigate the findings and prognosis of rheumatic fever (RF) patients seen in the past 20 years and to compare the last two decades. METHODS: The medical records of all RF patients admitted to Gazi University Department of Pediatric Cardiology during 1982-2002 were reviewed. The decade from 1.1.1982 to 31.12.1991 was designated as 1980s and the following decade as the 1990s. RESULTS: Among the 609 RF cases, there was no difference between the two decades regarding mean age, male/female ratio, most of the minor manifestations and findings of the preceding streptococcal infection. As the rate of carditis declined in 1990s, rates of arthritis and chorea increased. Severity of carditis and admissions with reactivation decreased during 1990s. The two decades did not differ regarding mean age, gender ratio, pericarditis rate, number and type of valvular involvement and sequel of carditis cases. Severity of carditis and number of valvular involvement influenced the first-year prognosis. Almost one-third of the arthritis cases had monoarthritis in both decades. Atypical cases with small-joint involvement were detected number of which increased during the 1990s. CONCLUSIONS: The two decades do not seem to differ regarding most of the manifestations of RF. More emphasis should be given to atypical cases such as small-joint involvement and monoarthritis and silent carditis. 相似文献
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OBJECTIVES: To investigate the relationship of specific nutrients and food items with oral precancerous lesions among tobacco users.
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day-1 ( P < 0.05). Ascorbic acid appeared to be protective against leukoplakia with the halving of risk in the two highest quartiles of intake (versus the lowest quartile: OR = 0.46 and 0.44, respectively; P < 0.10). A protective effect of tomato consumption was observed in leukoplakia and a suggestion of a protective effect of wheat in OSF.
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions. 相似文献
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions. 相似文献
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树突状细胞与肝脏疾病 总被引:9,自引:3,他引:6
免疫反应的产生首先是由抗原提呈细胞(antigenpresenting cells,APC)捕获抗原,经其加工处理后将抗原信息传递给T,B淋巴细胞,从而引发一系列的特异性免疫应答.APC包括树突状细胞(dendritic cells,DC)、巨噬细胞(MΦ)、B细胞等,其中DC是人体内最具潜能的抗原提呈细胞(APC),能在体内外直接激活纯真(naive)T细胞,提呈抗原给MHC-Ⅰ类限制性CD8+和MHC-Ⅱ类限制性CD4+T淋巴细胞,诱导特异性免疫应答[1-6]. 相似文献