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91.
T D Moon E P Harmon R E Hurst R A Bass M Colcolough G P Hemstreet 《The Journal of urology》1991,145(6):1236-1237
Quantitative fluorescence image analysis incorporates the 2 diagnostic techniques of cytological analysis with quantitation of deoxyribonucleic acid (DNA). Exfoliated urinary cells are ideal for analysis by this method, which allows the identification of "rare event" abnormal cells. We evaluated the urine from 50 children who had undergone cystoscopy or were catheterized for other reasons. The urine was free of infection by urinalysis. Cytological analysis demonstrated normal or atypical cells in all patients. Of the patients 1 (2%) had greater than 2 of 500 cells analyzed with greater than 5C DNA and 4 (8%) had greater than 2 of 500 cells with greater than 5C double stranded nucleic acid. These data suggest that it may be "normal" for urine to contain "rare event" abnormal cells. The significance of this finding is unclear at present. 相似文献
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Prognostic significance of c-kit mutation in localized gastrointestinal stromal tumors. 总被引:16,自引:0,他引:16
Tae Won Kim Hyoungnam Lee Yoon-Koo Kang Mi Sun Choe Min-Hee Ryu Heung Moon Chang Jung Sun Kim Jeong Hwan Yook Byung Sik Kim Jung Shin Lee 《Clinical cancer research》2004,10(9):3076-3081
PURPOSE: Constitutive mutational activation of c-kit has been found to be associated with the pathogenesis of gastrointestinal stromal tumors (GISTs). The prognostic significance of c-kit mutations, however, is still controversial. EXPERIMENTAL DESIGN: We examined 86 patients curatively resected for localized GIST. Genomic DNA was extracted from paraffin-embedded tumor tissues. Exons 9, 11, 13, and 17 of the c-kit gene were amplified by PCR and sequenced. RESULTS: Mutations in exon 11 were detected in 61 tumors, and mutations in exon 9 were observed in three tumors, whereas no mutations were detected in exons 13 or 17. The overall c-kit mutation frequency was 74%. Amino acid alterations in the 61 tumors with exon 11 mutations were deletion in 33 tumors, substitution in 20, both deletion and substitution in 4, insertion in 1, and duplication in 3. Histologically, tumors with c-kit mutations showed higher mitotic counts and higher cellularity. The 5-year relapse-free survival (RFS) in patients having GISTs with c-kit mutations was 21%, compared with 60% in those without c-kit mutations. Significantly higher RFS rates were observed in patients with tumors having mitotic counts < 5 mitoses/50 high power field, spindle-cell histology, tumor size < 5 cm, or gastric GISTs. Multivariate analyses indicated association of poorer RFS with a higher mitotic count > or = 5 of 50 high power fields; odds ratio (OR) = 3.0], presence of c-kit mutations (OR = 5.6), and a larger tumor size (> or = 5 cm; OR = 4.2). CONCLUSIONS: The presence of c-kit mutation, along with high mitotic count and larger tumor size, was an independent factor for poor prognosis in patients with localized GISTs. 相似文献
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The nutrition transition in South Korea 总被引:11,自引:0,他引:11
BACKGROUND: An accelerating shift from infectious to noncommunicable diseases and concurrent shifts in diet, activity, and body composition are universal trends but are especially apparent in middle- and lower-income countries. A unique nutrition transition has occurred in South Korea, a country that modernized earlier than most Asian countries did. OBJECTIVE: The purpose of this analysis was to describe the South Korean nutrition transition, focusing on specific features that other countries might follow to retain the healthful elements of their traditional diets. DESIGN: We used secondary data on economics, dietary intake, anthropometry, and causes of death, including a series of comparable nationally representative dietary surveys (the National Nutrition Survey). RESULTS: The structure of South Korea's economy, along with the country's dietary and disease patterns, began an accelerated shift in the 1970s. Major dietary changes included a large increase in the consumption of animal food products and a fall in total cereal intake. Uniquely, the amount and rate of increase in fat intake have remained low in South Korea. South Korea also has a relatively low prevalence of obesity compared with other Asian countries with similar or much lower incomes. CONCLUSIONS: The nutrition transition in South Korea is unique. National efforts to retain elements of the traditional diet are thought to have shaped this transition in South Korea in the midst of rapid economic growth and the introduction of Western culture. 相似文献
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In this review of the scientific literature the relationship between retinoids, carotenoids, and mammary carcinogenesis is examined. Several retinoids have shown promise as chemopreventive agents against chemically induced mammary carcinogenesis in mice and especially in rats. The most promising retinoids are retinyl acetate (RA) and N-(4-hydroxyphenyl)retinamide (4-HPR, fenretinide). In rats, dietary administration of these retinoids reduced tumor incidence and multiplicity, and increased the latency of DMBA or MNU-induced mammary cancers. In mice, 4-HPR reduced the number of hyperplastic alveolar nodules and the number of tumors in MTV- and MTV+ mice, respectively. Among retinoids, 4-HPR is at present the most promising analogue, due to its ability to concentrate in the mammary gland. The combination of 4-HPR with tamoxifen not only is more effective in suppressing breast cancer than either agent alone, but also inhibits the appearance of subsequent cancers following the surgical removal of the first tumor. These studies suggest that retinoids, like tamoxifen, may be applicable to the prevention of contralateral breast cancer in women who underwent breast cancer surgery. It is also becoming evident that differentiation therapy and chemoprevention can become attractive alternative approaches to intensive cytotoxic chemotherapy. The role of carotenoids in the prevention of mammary carcinogenesis, however, is ambiguous. Poor absorption and low levels of carotenoids that reach the target tissues complicate interpretation of data in rodent models of mammary carcinogenesis. Very few animal studies are presently available in which purified carotenoids were found effective against mammary carcinogenesis. These results do not justify undertaking clinical evaluation of individual carotenoids against breast cancer at this time. 相似文献