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101.
It is increasingly recognised that phenotypic plasticity, apparently driven by epigenetic mechanisms, plays a key role in tumour behaviour and markedly influences the important processes of therapeutic survival and metastasis. An important source of plasticity in malignancy is epithelial‐to‐mesenchymal transition (EMT), a common epigenetically controlled event that results in transition of malignant cells between different phenotypic states that confer motility and enhance survival. In this review, we discuss the importance of phenotypic plasticity and its contribution to cellular heterogeneity in oral squamous cell carcinoma with emphasis on aspects of drug resistance and EMT.  相似文献   
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Biliary tract cancers (BTCs) are a group of invasive neoplasms, with increasing incidence and dismal prognosis. In advanced disease, the standard of care is represented by first-line chemotherapy with cisplatin and gemcitabine. In subsequent lines, no clear recommendations are currently available, highlighting the need for novel therapeutic approaches.The PI3K/AKT/mTOR pathway is a core regulator of cell metabolism, growth and survival, and is involved in BTCs carcinogenesis and progression. Mutations, gene copy number alterations and aberrant protein phosphorylation of PI3K, AKT, mTOR and PTEN have been thoroughly described in BTCs and correlate with poor survival outcomes.Several pre-clinical evidences state the efficacy of PI3K/AKT/mTOR pathway inhibitors in BTCs, both in vitro and in vivo. In the clinical setting, initial studies with rapamycin analogs have shown interesting activity with an acceptable toxicity profile. Novel strategies evaluating AKT and PI3K inhibitors have risen serious safety concerns, pointing out the need for improved patient selection and increased target specificity for the clinical development of these agents, both alone and in combination with chemotherapy.This review extensively describes the role of the PI3K/AKT/mTOR pathway in BTCs and examines the rationale of its targeting in these tumors, with particular focus on clinical activity, toxicities and perspectives on further development of PI3K/AKT/mTOR pathway inhibitors.  相似文献   
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The study explored adult gerontology acute care nurse practitioner (AGACNP) student’s self-perception of confidence and competence in essential domains of nurse practitioner (NP) skills. A preclinical hospital immersion experience was developed to improve transition to the ACACNP role. AGACNP students participated in once-weekly sessions for 3 consecutive weeks, with 14 students completing the experience over a 3-year period. Data showed a 28.7% improvement in student’s self-perception of confidence and competence, with statistically significant improvement in clinical decision-making skills and NP role. AGACNP students requested additional days and appreciated direct faculty feedback, while faculty efficiently supported AGACNP role transition.  相似文献   
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王博  魏芳 《现代肿瘤医学》2020,(16):2901-2904
E-钙黏蛋白(E-cadherin)是一种主要存在于人和动物上皮的黏附分子,主要功能是维持正常上皮细胞形态和结构完整性。现已在多种肿瘤研究中发现,E-cadherin表达的下调,极易造成肿瘤细胞向外周组织发生浸润和远端转移,但与E-cadherin相关研究在妇科恶性肿瘤中进展缓慢,E-cadherin在子宫内膜癌、卵巢癌和宫颈癌病变过程的调控机制尚不完全清楚,而且肿瘤的发生和发展是多因素作用的过程,需要进一步加强研究,该文章就 E-cadherin在妇科三大妇科恶性肿瘤中表达的意义及研究进展进行综述。  相似文献   
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Outcomes following healthcare transition (HCT) from pediatric to adult HIV care are not well described. We sought to describe clinical outcomes following HCT within our institution among young adults with behavioral-acquired (N?=?31) and perinatally-acquired (N?=?19) HIV. We conducted a retrospective cohort study among HIV-infected adults who attempted transition from pediatric to adult HIV care within our institution. The primary end point was retention in care, defined as the completion of at least two visits over 12 months following linkage to adult care. Additional end points include time to linkage to adult care, and changes in CD4?+?T cell count and HIV RNA across time. Outcomes were compared between perinatal and behavioral HIV cohorts. Binary data were analyzed using the Fisher exact test and continuous data were analyzed using the Mann–Whitney test. Forty-three (86%) of 50 patients were successfully linked to adult care. The median time to linkage was 98 days. Fifty percent of patients achieved full retention in care at 12 months post-linkage. Though those with behavioral-acquired HIV attempted transfer at an older age, the groups did not differ in rates of linkage and retention in adult care. CD4?+?T cell counts and rates of viral suppression did not differ between pre- and post-HCT periods. Despite high rates of successful linkage to adult care in our study population, rates of retention in adult HIV care following HCT were low. These results imply that challenges remain in the adult HIV care setting toward improving the HCT process.  相似文献   
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Animal models have made and continue to make important contributions to neonatal medicine. For example, studies in fetal sheep have taught us much about the physiology of the fetal-to-neonatal transition. However, whereas animal models allow multiple factors to be investigated in a logical and systematic manner, no animal model is perfect for humans and so we need to understand the fundamental differences in physiology between the species in question and humans. Although most physiological systems are well conserved between species, some small differences exist and so wherever possible the knowledge generated from preclinical studies in animals should be tested in clinical trials. However, with the rise of evidence-based medicine the distinction between scientific knowledge generation and evidence gathering has been confused and the two have been lumped together. This misunderstands the contribution that scientific knowledge can provide. Science should be used to guide the gathering of evidence by informing the design of clinical trials, thereby increasing their likelihood of success. While scientific knowledge is not evidence, in the absence of evidence it is likely to be the best option for guiding clinical practice.  相似文献   
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