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Adolescents and young adults (AYAs) are underrepresented in cancer clinical trials (CCTs). Limited trial enrollment slows progress in improving survival rates and prevents the collection of valuable biospecimens. A systematic literature review was conducted to assess barriers and facilitators to AYA enrollment in CCTs and to identify opportunities to improve enrollment. The PubMed MEDLINE, Web of Science, Scopus, and PsycINFO databases were searched to identify studies relevant to AYA CCT enrollment. Eligibility criteria included the qualitative and/or quantitative evaluation of barriers and facilitators to AYA enrollment. One hundred fifty-five unique publications were identified; 13 were included in the final analysis. Barriers to AYA enrollment in CCTs included a lack of existing trials applicable to the patient population, limited access to available CCTs, and a lack of physician awareness of relevant trials. Facilitators of enrollment included optimizing the research infrastructure, improving the awareness of available CCTs among providers, and enhancing communication about CCTs between providers and patients. In conclusion, the limited available research reports institution- and patient-level barriers and facilitators to AYA CCT enrollment. Because of persistent disparities in AYA enrollment, there is an urgent need to further identify the barriers and facilitators to AYA CCT enrollment to determine actionable areas for intervention.  相似文献   
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The purpose of this study was to examine whether the symptoms experienced by patients with unstable angina (UA) differed from the symptoms experienced by patients with myocardial infarction (MI). Data were obtained from two studies: one examining the symptoms of MI (n=238) and one examining the symptoms of UA (n=100). Interviews were conducted after hospital admission at three medical centers in the Midwest. There were no differences between patients with MI or UA in age, gender, or race. The patients experiencing MI reported significantly more nausea (46% vs. 32%), vomiting (19% vs. 2%), indigestion (42% vs. 16%), and fainting (9% vs. 2%). The patients experiencing UA reported significantly more chest discomfort (97% vs. 87%), lightheadedness (52% vs. 39%), numbness in the hands (43% vs. 28%), and neck discomfort (31% vs. 13%). Patients with MI rated the peak intensity of the chest discomfort higher than patients with UA (mean 8.4 vs. mean 7.7).  相似文献   
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Polyubiquitin chains linked through the Lys48 residue of ubiquitin are most commonly associated with targeting proteins for proteosomal degradation. In contrast, polyubiquitin chains linked through the Lys63 residue of ubiquitin are associated with nonproteolytic functions such as signal transduction. The mechanism by which Lys63-linked polyubiquitin chains participate in signaling cascades has yet to be determined, but two recent publications (Wu et al., Nat Cell Bio 2006; 8:398-406 and Ea et al., Mol Cell 2006; 22:245-57) shed light on how this distinctive modification functions in NFkappaB activation by TNFalpha. Upon stimulation with TNFalpha, RIP1 undergoes Lys63-linked polyubiquitination. The polyubiquitin chain on RIP1 is recognized and bound by NEMO, the regulatory subunit of the IKK complex, and this binding is essential for NFkappaB activation by TNFalpha. Thus, Lys63-linked polyubiquitin chains critically connect components of NFkappaB signaling in a highly regulated manner.  相似文献   
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BACKGROUND: We recently showed that bone morphogenetic protein 7 (BMP7) is overexpressed in primary breast tumors. Here we explored the clinical significance of BMP7 expression in breast cancer. MATERIALS AND METHODS: This study included 483 breast cancer patients with complete clinicopathological information and up to 15 years of follow-up. Samples contained 241 lobular carcinomas, 242 ductal carcinomas, and 40 local recurrences. BMP7 protein expression was determined using immunohistochemistry. RESULTS: BMP7 was expressed in 47% of the primary tumor samples and 13% of the local recurrences. The primary tumors expressed BMP7 more often than the corresponding local recurrences (P = 0.004). BMP7 expression was dependent on the tumor subtype; 57% of the lobular carcinomas but only 37% of the ductal carcinomas were BMP7 positive (P = 0.0001). BMP7 expression was associated with accelerated bone metastasis formation (P = 0.040), especially in ductal carcinomas (P = 0.033), and multivariate analysis confirmed that BMP7 is an independent prognostic indicator for early bone metastasis development (P = 0.032). CONCLUSION: BMP7 is clearly associated with bone metastasis formation and thus might have clinical utility in identification of patients with increased risk of bone metastasis. This is the first time that bone inducing factor BMP7 has been linked to the bone metastasis process in breast cancer.  相似文献   
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Seppanen  S; Lehtinen  E; Holli  H 《Radiology》1978,127(2):377-380
Radiation doses of modern 100mm fluorography and full-scale radiography were compared experimentally and applied to hysterosalpingography. It was determined that 100mm fluorography reduced the doses by 28-29% per exposure and 37-47% per examination compared with full-scale radiography performed with fast tungstate screens in identical conditions (70-80 kV, 400 mA). The dose during one minute of videofluoroscopy was equivalent to the doses produced by one exposure in full-scale filming and three to four exposures in 100mm filming. Although electronic magnification in 100mm fluorography increases the doses by two or threefold, these are still less than the doses in full-scale radiography.  相似文献   
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The aim of this trial was to study the value of adding post-operative radiotherapy to lumpectomy in a subgroup of breast cancer patients with favourable patient-, tumour-, and treatment-related prognostic features. 152 women aged over 40 with unifocal breast cancer seen in preoperative mammography were randomly assigned to lumpectomy alone (no-XRT group) or to lumpectomy followed by radiotherapy to the ipsilateral breast (50 Gy given within 5 weeks, XRT group). All cancers were required to be invasive node-negative, smaller than 2 cm in diameter and well or moderately differentiated, to contain no extensive intraductal component, to be progesterone receptor-positive, DNA diploid, have S-phase fraction 相似文献   
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