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51.
The serrated pathway (SP) can be viewed as two parallel, but partially overlapping, arrays of colorectal precursor lesions, and their respective endpoint carcinomas, that are distinct from those of the conventional adenoma–carcinoma sequence (APC‐pathway). In this review we focus at the outset on the clinical impact, pathological features, molecular genetics and biological behaviours of the various SP cancers. Then we summarize the clinicopathological features, classification and molecular profiles of the two main precursor lesions that anchor the respective pathways: (i) sessile serrated adenoma/polyp (SSA/P), also called sessile serrated lesion (SSL), and (ii) traditional serrated adenoma (TSA). Activating mutations of the RAS–RAF–MAPK pathway initiate and sustain the lesions of the SP, and CpG island methylation of the promoter regions of tumour suppressor and DNA repair genes play the major role in their neoplastic progression. The SP includes microsatellite stable (MSS) carcinomas that are among the most biologically aggressive colorectal carcinomas (CRC), and also accounts for the great preponderance of sporadic hypermutated, mismatch repair (MMR)‐deficient or microsatellite instable (MSI) CRC. The identification, removal and appropriate classification of at‐risk SP precursors and surveillance of individuals who harbour these lesions present a challenge and opportunity for CRC prevention and mortality reduction.  相似文献   
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目的:探讨miR-26b参与原发性肝细胞肝癌(HCC)侵袭的机制。方法:在细胞培养液中培养人肝细胞系HL-7702和HCC细胞各系Hepb-3、HuH-7、MHCC97-L、MHCC97-H。实时荧光定量PCR法(qRT-PCR)检测miR-26b的表达水平;用miR-26b mimics、miR-26b inhibitors和Notch1-siRNA分别转染HCC细胞;MTT实验检测转染后HCC细胞的活力;采用Western blot检测Notch1受体蛋白表达水平的变化;Transwell小室测定不同处理后的HCC细胞的侵袭能力。结果:人正常肝细胞系HL-7702和HCC细胞系Hepb-3、HuH-7、MHCC97-L、MHCC97-H中的miR-26b相对表达含量随其侵袭和迁移能力的升高而依次下降;抑制miR-26b的表达,Notch1受体蛋白表达明显增高,而此时HCC细胞的侵袭性显著增强;相反,上调miR-26b的表达,Notch1受体蛋白表达明显降低,而HCC细胞侵袭性显著下降;miR-26b可能通过调控Notch1信号通路调节HCC细胞侵袭性。结论:miR-26b通过负调控Notch1信号通路抑制HCC细胞侵袭能力,为HCC侵袭的机制奠定了理论基础,miR-26b可能成为HCC治疗的新靶点。  相似文献   
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综述护士个人-组织契合度的概念、评估工具以及现状,通过分析影响护士个人-组织契合度的因素,明确提高护士个人-组织契合度的策略,以期为护理管理者改善护士工作环境,构建良好稳固的护理队伍提供参考.  相似文献   
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聚酰胺—胺树枝状聚合物(PAMAM)作为一种新型超支化大分子聚合物,因其出色的化学和生物学特性,一直被众学者称之为“人工蛋白”。 PAMAM的特点是存在内部空腔,并含有大量的反应性末端基团,这些结构使得PAMAM可以被用作仿生大分子,模拟天然有机基质在牙体组织表面进行仿生矿化,即PAMAM作为有机模板调控矿物质成核以及晶体的生长,以此来建造比传统的异体材料更加理想的牙体修复材料。本文就 PAMAM 诱导牙体硬组织仿生矿化的研究进展作一综述。  相似文献   
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Background:Gastrointestinal complications and malnutrition are common problems that affect postoperative rehabilitation and survival of patients with esophageal cancer. Evidence has shown that probiotics have a positive effect on improving gastrointestinal complications and nutritional status of patients with esophageal cancer after surgery, but there is a lack of prospective studies on this topic. We designed this prospective randomized controlled trial to evaluate the effects of probiotics on gastrointestinal complications and nutritional status in patients with postoperative esophageal cancer.Methods:This is a prospective, randomized, double-blind, placebo-controlled trial. It was approved by the Clinical Research Ethics Committee of our hospital. 192 patients will be randomly divided into probiotics group and the placebo group in a 1:1 ratio. After operation, probiotics and placebo will be given orally for 8 weeks. The indexes of nutritional status and incidence of digestive tract complications will be recorded and the data will be analyzed by SPSS 18.0 software.Discussion:This study will evaluate the effect of probiotics on gastrointestinal complications and nutritional status of postoperative patients with esophageal cancer. The results of this study will provide clinical basis for the use of probiotics in postoperative treatment of esophageal cancer.Trial registration:OSF Registration number: D DOI 10.17605/OSF.IO/QHW86  相似文献   
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Introduction: Malnutrition increases the risk of cancer treatment-related complications. Nutritional intervention is beneficial for the outcomes of outpatients with cancer. This study investigated the impacts of nutrition consultation and care on energy intake and weight change in inpatients receiving cancer treatment.

Methods: We conducted a longitudinal study, enrolling 3221 inpatients with head and neck, lung, hepatobiliary, upper gastrointestinal, colorectal, breast, or gynecological cancer who received at least two nutrition consultations between April 2010 and July 2015. In every consultation, a dietitian calculated the total energy requirement and the actual energy intake was assessed using a 24-h dietary recall.

Results: Patients with head and neck cancer lost the most weight (1.16?kg/mo). For every consultation, a 0.03-kg weight gain per month was observed (P?=?0.001). The average energy consumption percentage (% estimated energy requirement) at the third consultation was 87.0%. After controlling for potential covariates, the energy consumption percentages at the third, fourth, fifth–seventh, eighth, and subsequent consultations were significantly higher than those at the first consultation (P?<?0.05).

Conclusion: For oncology inpatients, routine screening and at least three active nutrition consultations with dietitians effectively improved energy intake and preserved body weight.  相似文献   

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