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排序方式: 共有631条查询结果,搜索用时 15 毫秒
1.
David G Hicks Brian J Yoder Sarah Short Shannon Tarr Nichole Prescott Joseph P Crowe Andrea E Dawson G Thomas Budd Steven Sizemore Muzaffer Cicek Toni K Choueiri Raymond R Tubbs Daniel Gaile Norma Nowak Mary Ann Accavitti-Loper Andra R Frost Danny R Welch Graham Casey 《Clinical cancer research》2006,12(22):6702-6708
PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors. 相似文献
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Poly(lactide-co-glycolide) microspheres as a moldable scaffold for cartilage tissue engineering 总被引:2,自引:0,他引:2
This study demonstrates the use of biodegradable poly(lactide-co-glycolide) (PLG) microspheres as a moldable scaffold for cartilage tissue engineering. Chondrocytes were delivered to a cylindrical mold with or without PLG microspheres and cultured in vitro for up to 8 weeks. Cartilagenous tissue formed using chondrocytes and microspheres maintained thickness, shape, and chondrocyte collagen type II phenotype, as indicated by type II collagen staining. The presence of microspheres further enhanced total tissue mass and the amount of glycosaminoglycan that accumulated. Evaluation of microsphere composition demonstrated effects of polymer molecular weight, end group chemistry, and buffer inclusion on tissue-engineered cartilage growth. Higher molecular weight PLG resulted in a larger mass of cartilage-like tissue formed and a higher content of proteoglycans. Cartilage-like tissue formed using microspheres made from low molecular weight and free carboxylic acid end groups did not display increases in tissue mass, yet a modest increased proteoglycan accumulation was detected. Microspheres comprised of PLG with methyl ester end groups yielded a steady increase in tissue mass, with no real increase in matrix accumulation. The microencapsulation of Mg(OH)(2) had negative effects on tissue mass and matrix accumulation. The data herein reflect the potential utility of a moldable PLG-chondrocyte system for tissue-engineering applications. 相似文献
3.
Close Carolina Elek Elvira Roberts Cheryl A. Dunlap Laura J. Graham Phillip W. Scaglione Nichole M. Palen Lori-Ann Clarke Thomas 《Prevention science》2021,22(8):1071-1085
Prevention Science - This prospective cost analysis addresses a gap in the prevention literature by providing estimates of the typical real-world costs to implement community interventions focused... 相似文献
4.
Karla McGregor Tim Arbisi-Kelm Nichole Eden 《International journal of speech-language pathology》2017,19(1):43-57
Purpose: To describe the word-learning problems characteristic of developmental language impairment (LI).Method: College students with LI (n?=?39) or normal language development (ND, n?=?40) attempted to learn novel word forms. Training for half of the words was meaning-focused; training for the other half was form-focused. Form recognition and stem completion tasks administered immediately after training tapped encoding of the lexical configuration and a repetition of the stem completion task one week later tapped consolidation. A visual world paradigm tapped lexical engagement.Result: At the immediate post-test, the LI group was poorer at recognition and completion of word forms than their ND peers, suggesting a deficit in encoding the lexical configuration. However, the gap between the LI and ND groups in stem completion did not grow over the week, suggesting intact consolidation. Form-focused training yielded better performance than meaning-focused training at immediate- and one week tests. For both groups, newly trained words slowed the recognition of familiar English words, revealing lexical engagement.Conclusion: The encoding of word-form configurations is challenging for some, but not all, college students with LI. Training that encourages a focus on the form may be a useful part of vocabulary intervention for those affected. 相似文献
5.
Joel Hillhouse Rob Turrisi Nichole M. Scaglione Michael J. Cleveland Katie Baker L. Carter Florence 《Prevention science》2017,18(2):131-140
Youthful indoor tanning as few as ten sessions can increase the risk of melanoma by two to four times with each additional session adding another 2 % to the risk. Recent research estimates that indoor tanning can be linked to approximately 450,000 cases of skin cancer annually in the USA, Europe, and Australia. Despite these risks, indoor tanning remains popular with adolescents. This study tested the efficacy of a web-based skin cancer prevention intervention designed to reduce indoor tanning motivations in adolescent females. A nationally representative sample of 443 female teens was enrolled from an online panel into a two-arm, parallel group design, randomized controlled trial. Treatment participants received an appearance-focused intervention grounded in established health behavior change models. Controls viewed a teen alcohol prevention website. Outcome variables included willingness and intentions to indoor tan, willingness to sunless tan, and measures of indoor tanning attitudes and beliefs. The intervention decreased willingness and intentions to indoor tan and increased sunless tanning willingness relative to controls. We also examined indirect mechanisms of change through intervening variables (e.g., indoor tanning attitudes, norms, positive and negative expectancies) using the product of coefficient approach. The web-based intervention demonstrated efficacy in changing adolescent indoor tanning motivations and improving their orientation toward healthier alternatives. Results from the intervening variable analyses give guidance to future adolescent skin cancer prevention interventions. 相似文献
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Anthony J. Bonito Costica Aloman M. Isabel Fiel Nichole M. Danzl Sungwon Cha Erica G. Weinstein Seihwan Jeong Yongwon Choi Matthew C. Walsh Konstantina Alexandropoulos 《The Journal of clinical investigation》2013,123(8):3510-3524
TRAF6, an E3 ubiquitin protein ligase, plays a critical role in T cell tolerance by regulating medullary thymic epithelial cell (mTEC) development. mTECs regulate T cell tolerance by ectopically expressing self-antigens and eliminating autoreactive T cells in the thymus. Here we show that mice with mTEC depletion due to conditional deletion of Traf6 expression in murine thymic epithelial cells (Traf6ΔTEC mice) showed a surprisingly narrow spectrum of autoimmunity affecting the liver. The liver inflammation in Traf6ΔTEC mice exhibited all the histological and immunological characteristics of human autoimmune hepatitis (AIH). The role of T cells in AIH establishment was supported by intrahepatic T cell population changes and AIH development after transfer of liver T cells into immunodeficient mice. Despite a 50% reduction in natural Treg thymic output, peripheral tolerance in Traf6ΔTEC mice was normal, whereas compensatory T regulatory mechanisms were evident in the liver of these animals. These data indicate that mTECs exert a cell-autonomous role in central T cell tolerance and organ-specific autoimmunity, but play a redundant role in peripheral tolerance. These findings also demonstrate that Traf6ΔTEC mice are a relevant model with which to study the pathophysiology of AIH, as well as autoantigen-specific T cell responses and regulatory mechanisms underlying this disease. 相似文献
9.
Vardhmaan Jain MD Ankur Kalra MD Muhammad Siyab Panhwar MD Agam Bansal MD Amy Nowacki PhD Kirtipal Bhatia MD Tanush Gupta MD Nichole L. Ineman MSN Safi U. Khan MD Amar Krishnaswamy MD Grant W. Reed MD Rishi Puri MBBS PhD Samir R. Kapadia MD Lars G. Svensson MD PhD Anmar Kanaa'N MD Joseph A. Lahorra MD 《Journal of the American Geriatrics Society》2021,69(5):1363-1369
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