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51.
52.
Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Previous studies have found that microRNAs (miRNAs) play key roles in drug resistance; however, the role of miRNA‐373‐3p (miR‐375‐3p) in CRC remains unclear. The current study aimed to explore the potential function of miR‐375‐3p in 5‐fluorouracil (5‐FU) resistance. MicroRNA‐375‐3p was found to be widely downregulated in human CRC cell lines and tissues and to promote the sensitivity of CRC cells to 5‐FU by inducing colon cancer cell apoptosis and cycle arrest and by inhibiting cell growth, migration, and invasion in vitro. Thymidylate synthase (TYMS) was found to be a direct target of miR‐375‐3p, and TYMS knockdown exerted similar effects as miR‐375‐3p overexpression on the CRC cellular response to 5‐FU. Lipid‐coated calcium carbonate nanoparticles (NPs) were designed to cotransport 5‐FU and miR‐375‐3p into cells efficiently and rapidly and to release the drugs in a weakly acidic tumor microenvironment. The therapeutic effect of combined miR‐375 + 5‐FU/NPs was significantly higher than that of the individual treatments in mouse s.c. xenografts derived from HCT116 cells. Our results suggest that restoring miR‐375‐3p levels could be a future novel therapeutic strategy to enhance chemosensitivity to 5‐FU.  相似文献   
53.
TP53 alterations are frequent relapse‐acquired mutations in childhood acute lymphoblastic leukemia (ALL). The present study evaluated the clinical significance of relapsed childhood ALL in Taiwan. Diagnostic and/or relapsed bone marrow or peripheral blood was obtained from 111 children with relapsed ALL who were initially treated by using Taiwan Pediatric Oncology Group (TPOG) ALL protocols from January 1997 to May 2018. Mutations were detected by PCR and sequencing, as well as by multiplex ligation‐dependent probe amplification to detect copy number alterations. Copy number and/or sequence alterations of TP53 were detected in 29% (28 of 98) and in 46% (6 of 13) of patients with relapsed B‐cell and T‐cell ALL, respectively. This incidence was much higher than that in several similar studies conducted in Caucasian populations. Seventy percent of all TP53 alterations were gained at relapse in 67 matched samples by back‐tracking matched diagnostic samples. TP53 alterations were associated with lower 5‐year event‐free survival (EFS) and overall survival (OS) rates (P = .013 and P = .0002, respectively). Multivariate analysis confirmed the prognostic significance of TP53 alterations. Forty‐five patients received hematopoietic stem‐cell transplantations post‐relapse. Patients with TP53 alterations (14/45) had inferior 5‐year EFS and OS than patients without TP53 alterations after transplantation (P = .002 and P = .001, respectively). The significance of these TP53 alterations for patients who received transplantations was confirmed by multivariate analysis. In conclusion, TP53 alterations were enriched and useful as prognostic markers in relapsed childhood ALL.  相似文献   
54.
刘蕤  陈紫雯  华桂丰  王立强  萨翼  刘昶 《中草药》2020,51(18):4829-4836
目的建立保健食品原料评价体系(Functional Food Crude Materials Evaluation System,FUFMES),为保健食品原料目录排名提供科学依据与技术保障。方法首先,利用文献调研和多轮专家访谈方法筛选FUFMES的指标并确定其层级关系;第二,使用层次分析法(Analytic Hierarchy Process,AHP)计算指标权重,具体方法是依据专家打分构建判断矩阵,利用R语言进行一致性检验与最大特征根检验,得出各级指标权重;第三,使用极值法计算原料的单个指标值;第四,利用线性加权综合法得到每种原料的评价指数并据此进行排名;最后,将获得的分析结果与专家评价结果进行比较。结果 FUFMES包括6个一级指标、39个二级指标、11个三级指标。利用FUFMES对9种保健食品原料进行评价,获得的评价指数依次是:西洋参(0.49)、人参(0.48)、银杏叶(0.21)、灵芝孢子粉(0.08)、鱼油(0.06)、螺旋藻(0.03)、辅酶Q10(0.02)、褪黑素(0.01)、大蒜油(-0.03)。基于该评价指数的排名结果与专家评价结果显示了较高一致性。结论构建了科学、完整的FUFMES,FUFMES将成为保健食品原料目录评价与排名的有力工具,为推进保健食品原料备案制提供科学依据与技术保障。  相似文献   
55.
Abstract

Cadmium (Cd) as environmental pollutant can induce severe damage, particularly to the testis. This study investigated the effects of Caffeic acid phenethyl ester (CAPE) on testicular dysfunction induced by Cd. Adult mice were intraperitoneally injected with cadmium chloride (CdCl2) with different doses of CAPE pretreatment. After CdCl2 injection, body/testis weight ratio decreased, Cd levels accumulated and zinc levels decreased in testis. Furthermore, Cd intoxication caused a significant increase of oxidative stress levels, antioxidant enzymes activities, and glutathione levels. Interestingly, significant improvements were observed after the administration of CAPE. Our results demonstrated the protective effect of CAPE, linking Cd testicular dysfunction to oxidative stress.  相似文献   
56.
ABSTRACT

Little guidance is available to clinicians on how to talk about weight with their patients. The aim of this study is to explore youth preferences for weight-related conversations. Participants came from the National MyVoice Text Message Cohort. Between 7/2017 and 01/2018, 952 MyVoice participants provided open-ended responses via text message to three questions about weight-related conversations (“Has your doctor ever talked to you about weight?”, “What did he or she say?”, and “What should a doctor NOT say when talking about weight?”). The presence of themes was coded using standard qualitative methods. Of the 952 respondents, 568 (60%) reported that their doctor had talked with them about weight. Of these, 85% indicated that their doctor had notified them of their weight, BMI, or weight status and/or the need to change their body weight and 16% had doctors who provided advice about weight control. Eight themes emerged from the analysis of responses to the question “What should a doctor NOT say when talking about weight?”. The two most common themes were: (1): Avoid stigmatizing terms/language (32%); and (2) Do not shame patient for their weight (25%). Findings suggest that weight-related conversations do not reflect the preferences of the youth they are designed to benefit. Youth recommended that clinicians focus on health and sustainable behavioral solutions, avoid stigmatizing language and comparing them to others, and be aware of the potential harm associated with making assumptions that conflate weight with health behaviors, morality, or appearance.  相似文献   
57.
目的 制备吸附重组戊型肝炎病毒(hepatitis E virus,HEV)P179抗原的海藻酸钠/壳聚糖微球混悬制剂,并观察其免疫效果。方法 乳化法制备海藻酸钠/壳聚糖微球,采用不同海藻酸钠浓度、混合乳化剂添加量、混合乳化剂亲水亲油平衡值设计正交试验,确定最佳制备工艺参数。将重组HEV P179抗原吸附在最佳工艺制备的微球表面,制备吸附重组HEV P179的海藻酸钠/壳聚糖微球混悬制剂,皮下多点免疫BALB/c小鼠,测定其诱导小鼠产生特异性IgG抗体的能力,与同剂量含弗氏佐剂的重组HEV P179免疫制剂对比。结果 经正交试验确定乳化最佳工艺参数为:海藻酸钠质量分数1%、混合乳化剂体积分数2%,混合乳化剂亲水亲油平衡值4。制备的微球平均粒径为6.73 μm(分布范围3.90~9.10 μm,方差1.78 μm),形态较为均一,透射电镜观察结果与双层球体及内部疏松多孔的微球结构特点相符。用此条件制备抗原质量浓度为500 μg/ml的混悬制剂,微球对抗原的吸附率为90.64%。免疫效果观察试验结果表明,皮下多点免疫试验中微球制剂诱导特异性IgG抗体的能力优于含弗氏佐剂抗原。结论 成功制备了吸附重组HEV P179的海藻酸钠/壳聚糖微球混悬制剂,且诱导产生特异性IgG抗体的能力优于含弗氏佐剂抗原,为其在新型实验动物超敏制剂中的应用奠定了基础。  相似文献   
58.
BackgroundThe American Radium Society (ARS) Appropriate Use Criteria brain malignancies panel systematically reviewed (PRISMA [Preferred Reporting Items for Systematic Reviews and Meta-Analyses]) published literature on neurocognitive outcomes after stereotactic radiosurgery (SRS) for patients with multiple brain metastases (BM) to generate consensus guidelines.MethodsThe panel developed 4 key questions (KQs) to guide systematic review. From 11 614 original articles, 12 were selected. The panel developed model cases addressing KQs and potentially controversial scenarios not addressed in the systematic review (which might inform future ARS projects). Based upon quality of evidence, the panel confidentially voted on treatment options using a 9-point scale of appropriateness.ResultsThe panel agreed that SRS alone is usually appropriate for those with good performance status and 2–10 asymptomatic BM, and usually not appropriate for >20 BM. For 11–15 and 16–20 BM there was (between 2 case variants) agreement that SRS alone may be appropriate or disagreement on the appropriateness of SRS alone. There was no scenario (among 6 case variants) in which conventional whole-brain radiotherapy (WBRT) was considered usually appropriate by most panelists. There were several areas of disagreement, including: hippocampal sparing WBRT for 2–4 asymptomatic BM; WBRT for resected BM amenable to SRS; fractionated versus single-fraction SRS for resected BM, larger targets, and/or brainstem metastases; optimal treatment (WBRT, hippocampal sparing WBRT, SRS alone to all or select lesions) for patients with progressive extracranial disease, poor performance status, and no systemic options.ConclusionsFor patients with 2–10 BM, SRS alone is an appropriate treatment option for well-selected patients with good performance status. Future study is needed for those scenarios in which there was disagreement among panelists.  相似文献   
59.
目的:探索易产生艾烟刺激反应的针灸师人群流行病学特征,为临床艾烟安全性防护提供进一步指导;进一步验证网络调查的可行性。方法:自制艾烟机体反应调查问卷,对临床长期从事艾灸工作的针灸医师进行面对面问卷调查,运用Logistic回归模型分析影响针灸师易产生刺激反应的因素,获取对艾烟刺激敏感针灸师人群的流行病学特征。结果:共获取733例有效数据。多因素Logistic回归模型分析显示,慢性呼吸疾病史是接触艾烟后产生咳嗽、喉中有痰、气喘、呼吸困难、短气、鼻干刺激反应的影响因素(P<0.05,P<0.01);女性发生咳嗽、流泪、鼻干刺激反应的风险性高于男性(P<0.05,P<0.01);吸烟者发生眼干、眼痛的风险性高于不吸烟者(P<0.05);二手香烟暴露者发生短气的风险性高于非二手烟暴露者(P<0.05)。指数趋势线分析表明,网络调查和面对面调查所反映的机体刺激反应结果基本一致。结论:针灸师长期接触艾烟后产生机体刺激反应与慢性呼吸疾病史、女性、吸烟或二手香烟暴露有关,应对这类人群予以重点关注。网络问卷调查可用于艾烟安全性流行病学调查。  相似文献   
60.
Second primary cancer is prevalent in patients with gastrointestinal (GI) cancer, for which lung cancer is the most common and associated with high lethality. Image screening for lung cancer was proved to be effective in early diagnosis and lower mortality. However, trials of screen for lung cancer generally excluded patients with a previous diagnosis of malignancy. The study aimed to investigate the outcome of second primary lung cancer and the factor that improve survival in patients with hepato-GI cancer.A total of 276 patients with secondary lung cancer were found among 3723 newly-diagnosed lung cancer patients diagnosed in Chang Gung Memorial Hospital, between 2010 and 2014. Patients’ clinical characteristics, stages and survival were recorded and analyzed. The patients were separated into 2 groups: Group I was defined as lung cancer detected in original primary cancer clinic and group II patients defined as lung cancer detected in other medical places.Sixty-nine cases with primary GI-hepatic and secondary lung cancer were diagnosed (42 (60.8%) in Group I and 27 (39.1%) in Group II). Although both groups had comparable primary cancer stages and treatment, more patients in Group I than Group II were diagnosed as early stage lung cancer (stage I-II: 40.5% vs 11.1%; P = .023). Group II had larger lung tumor sizes than Group I (4.7 vs 3.5 cm; P = .025). Group I showed better 5-year overall survival than Group II (P = .014, median survival: 27 vs 10 months). Among Group II, only 37% had received image follow up in clinic compared with 67% of Group I cases (P = .025). Patients with chest image follow up in clinics also had better 5-year overall survival (P = .043).GI-hepatic cancer was the most common primary malignancy in the lung cancer cohort. Patients had better survival outcome when secondary lung cancer was diagnosed in original primary cancer clinic. Chest image screening strategy may contribute better survival in secondary lung cancer due to detection at an earlier stage.  相似文献   
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