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排序方式: 共有7743条查询结果,搜索用时 15 毫秒
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In vivo light scattering measurements for detection of precancerous conditions of the cervix 总被引:1,自引:0,他引:1
Mourant JR Bocklage TJ Powers TM Greene HM Bullock KL Marr-Lyon LR Dorin MH Waxman AG Zsemlye MM Smith HO 《Gynecologic oncology》2007,105(2):439-445
OBJECTIVE: To examine the utility of in vivo elastic light scattering measurements to diagnose high grade squamous interepithelial lesions (HSIL) of the cervix. METHODS: A newly developed fiber optic probe was used to measure light transport in the cervical epithelium of 36 patients undergoing standard colposcopy. Both unpolarized and polarized light transport were measured in the visible and near-infrared. Spectroscopic results of 29 patients were compared with histopathology of the measured sites using ROC curves, MANOVA and logistic regression. RESULTS: Three spectroscopic parameters are statistically different for HSIL compared with low-grade lesions and normal tissue. When these three spectroscopic parameters are combined, retrospective sensitivities and specificities for HSIL versus non-HSIL are 100% and 80%, respectively. CONCLUSIONS: Reflectance measurements of elastically scattered light show promise as a non-invasive, real-time method to discriminate HSIL from other abnormalities and normal tissue. These results compare favorably with those obtained by fluorescence alone and by fluorescence combined with light scattering. 相似文献
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Neo-angiogenesis appears to be a critical feature of tumor growth, migration, and metastasis. Therefore, inhibition of angiogenesis is an appealing strategy for treatment of cancer. Since angiogenesis is the result of several mechanistic processes, controlled by numerable pro- and anti-angiogenic factors and their receptors, multiple possibilities to prevent or reverse tumor-induced neo-vascularization have been proposed. Of these, currently, the most promising approach has been the use of bevacizumab, a humanized monoclonal antibody directed against the most potent pro-angiogenic factor, vascular endothelial growth factor (VEGF). Bevacizumab has been shown to be active in several malignancies, in particular colo-rectal cancer. Although early studies of bevacizumab in far-advanced metastatic breast cancer were disappointing, the results of a recently reported clinical trial by the Eastern Oncology Group comparing first line paclitaxel with or without bevacizumab has demonstrated statistically significant improvements in response rates and time progression. Ongoing studies are now investigating the benefits of bevacizumab with other chemotherapeutic and biologic agents in early metastatic disease as well as in the adjuvant setting. Other anti-angiogenic agents remain in early clinical trials. Small molecular inhibitors of VEGF receptor tyrosine kinase activity, such as sunitinib, appear promising. Nearly 40 years after it was first proposed, inhibition of angiogenesis appears to be gaining a role in medical oncology. 相似文献
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Georgia Robins Sadler Paula R. Beerman Kathy Lee Jenny Hung Helene Nguyen Janet Cho Wennie Huang 《Journal of cancer education》2012,27(4):612-617
Asian American women's historically low breast cancer mortality rate has remained constant as rates decreased for all other races. From 2000 to 2004, a randomized controlled trial explored the Asian grocery store-based breast cancer education program's impact on Chinese, Filipino, Korean, and Vietnamese women (n?=?1,540). Women aged 40 and older and non-adherent for annual screening mammograms were more likely to schedule a mammogram after receiving the breast cancer education program than women randomized to the prostate cancer program (X 2?=?3.85, p?=?0.05). With the right program ingredients, late adopters of breast cancer screening can be prompted to change. 相似文献
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Our previous study had demonstrated that Astragalus saponins (AST) could reduce the side effects of orthodox chemotherapeutic drugs, while concurrently promote antitumor activity. In the present study, we attempted to investigate the potential synergistic anticarcinogenic effects of AST and a vinca alkaloid vinblastine (VBL). Reduced expression of key proangiogenic and metastatic factors including VEGF, bFGF, metalloproteinase (MMP)-2, and MMP-9 was detected in VBL-treated colon cancer cells, with further downregulation by combined VBL/AST treatment. Subsequently, VBL or AST decreased LoVo cell invasiveness, with further reduction when the drugs were cotreated. Significant growth inhibition and cell cycle arrest at G2/M phase were achieved by either drug treatment with apparent synergistic effects. VBL-induced apoptosis was confirmed but found to be unrelated to induction of the novel apoptotic protein NSAID-activated gene 1. In vivo study in tumor xenograft indicates that combined VBL/AST treatment resulted in sustained regression of tumor growth, with attenuation of the neutropenic and anemic effects of VBL. In addition, downregulation of proangiogenic and proliferative factors was also visualized, with boosting effect by combined drug treatment. These findings have provided evidence that AST combined with adjuvant chemotherapeutics like VBL could alleviate cancer development through diversified modes of action, including the regulation of angiogenesis. 相似文献
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Nagi B. Kumar Jeffrey P. Krischer Kathy Allen Diane Riccardi Karen Besterman-Dahan Raoul Salup 《Nutrition and cancer》2013,65(2):169-175
Our purpose was to evaluate the safety of 80 mg of purified isoflavones administered to men with early stage prostate cancer. A total of 53 men with clinically localized prostate cancer, Gleason score of 6 or below, were supplemented with 80 mg purified isoflavones or placebo for 12 wk administered in 2 divided doses of 40 mg to provide a continuous dose of isoflavones. Compliance, changes in plasma isoflavones, and clinical toxicity were analyzed at baseline, 4, and 12 wk. A total of 50 subjects completed the 12-wk intervention. A continuous, divided-dose administration of 80 mg/day of purified isoflavones at amounts that exceeded normal American dietary intakes significantly increased (P < 0.001) plasma isoflavones in the isoflavone-treated group compared to placebo and produced no clinical toxicity. With the current evidence on the cancer preventive properties of isoflavones, these results are significant and offer promise for these phytochemicals to be developed as potent agents to prevent cancer progression. 相似文献