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51.
Reactive oxygen species (ROS) are cytotoxic at higher concentration resulting in cell death, mutations, chromosomal aberrations or carcinogenesis. In this study DNA was modified by singlet oxygen and superoxide anion radicals generated by illumination of riboflavin under 365 nm UV-light. The modified DNA induced high titre antibodies in experimental animals. In enzyme immunoassay, serum antibodies from cancer patients (n = 34) showed a higher recognition of the modified DNA, as compared to the native form. This was further confirmed by the gel-shift assay. Immune IgG were used as a probe to detect oxidative lesions in the DNA of cancer patients. DNA isolated from lymphocytes of cancer patients proved to be an appreciable inhibitor of the experimentally induced antibodies against the ROS-DNA. This indicates the presence of oxidative lesions in the DNA obtained from cancer patients. The results show that ROS induced oxidative damage to DNA in cancer patients generate neo-epitopes that are alien for the immune system, resulting in autoantibody formation.  相似文献   
52.
Breast cancer is one of the most feared diseases in contemporary Western society. Popular women's magazines are important sources of information about and orientation to the disease. The current study applies problematic integration theory in an interpretive analysis of all breast cancer articles appearing in five top-circulating women's magazines between 1997 and 2002. In so doing, the study illuminates two major challenges (uncertainty and ambivalence) and several imperfect approaches to coping constructed in this discourse (simplification, information-seeking/provision, affect management, trusting intuition, sustaining hope, and metaphoric reframing). These results have several clear and important practical implications and highlight a major and largely untried direction for future research.  相似文献   
53.
研究目的:优化获得血红密孔菌(P.sanguineus)的最佳培养基组成,提高耐热漆酶的产量。创新要点:获得了目前文献报道的最高水平的漆酶活力。研究方法:通过单因素试验研究了不同培养基(番茄汁、麦麸、麦芽提取物和葡萄糖细菌蛋白胨培养基)和不同组合诱导剂(大豆油、阿魏酸、没食子酸、二甲基苯胺、酸性蓝62和活性蓝19分别与硫酸铜组合诱导剂)对P.sanguineus产耐热漆酶的影响。在此基础上采用中心组合试验设计,进一步研究了番茄汁培养基结合硫酸铜和大豆油组合诱导剂对P.sanguineus产耐热漆酶的影响。利用SAS10.0和响应面分析方法对试验结果进行了统计分析和建立回归模型。重要结论:通过中心组合设计优化得出P.sanguineus产耐热漆酶的最优培养基条件:以36.8%番茄汁为培养基,以3 mmol/L硫酸铜和1%大豆油作为组合诱导剂。该条件下在10 L搅拌槽生物反应器中漆酶活力达到了143 000 IU/L(2,2'-联氮双(3-乙基苯并噻唑啉-6-磺酸)为底物,pH值为3.0)。  相似文献   
54.
BackgroundCancer is a life-threatening disease that affects approximately 18 million individuals worldwide. Breast cancer is the most common female neoplasm globally with more than 276,480 new cases of invasive breast cancer expected to be diagnosed in women in the U.S. alone in 2020. Genetic and epigenetic factors play role in the carcinogenesis and progression of this disease. In this study, MCF-7 adenocarcinoma cells were transfected with CRISPR/Cas9 plasmid to either knock out CDK11 or to activate CDH1. Treated cells were allografted into the mammary glands of female rats (150–190 g, 6–8 weeks) to evaluate the capability of these cells to control cancer progression and metastasis.ResultsqPCR data revealed a significant downregulation of CDK11 and upregulation of CDH1. Cell cycle analysis and apoptosis assays indicated the knockout of CDK11 and simultaneous activation of CDH1 resulted in cell cycle arrest at G2/M phase and accumulation of cells at G2. Meanwhile, the percentage of cells that underwent late apoptosis increased in both genome editing hits. Histopathological sectioning data indicated that untransfected MCF-7 cells were capable of developing tumors in the mammary gland and initiation g angiogenesis. Transfected cells significantly restricted cancer cell infiltration/invasion by minimally localizing tumors and inhibiting angiogenesis.ConclusionsAlthough further investigation is needed, the present data indicate the potentiality of using CRISPR/Cas9-based therapy as a promising approach to treat breast cancer. Impact: these data indicate targeting cancer-related genes via any genome editing tool might represent a novel approach to combat cancer.How to cite: Al-Mulhim F, Alqosaibi AI, Al-Muhnna A, et al. CRISPR/Cas9-mediated activation of CDH1 suppresses metastasis of breast cancer in rats. Electron J Biotechnol 2021;53. https://doi.org/10.1016/j.ejbt.2021.06.002  相似文献   
55.
颈椎病是指因颈椎间盘退行性变、颈椎肥厚增生以及颈部损伤等引起的疾病,是中、老年人的常见病、多发病之一,多见于40岁以上病人。随着人们工作性质和工作条件的改变,颈椎病的发病年龄已经提前到40岁以前,已成为骨科的常见病,需要手术治疗的病人也越来越多,颈椎病病人的护理已成为骨科病房的重要工作之一。  相似文献   
56.
Twenty-four hour urinary albumin excretion (UAE) is considered as gold standard method for albuminuria measurement, but collection of 24-h urine is inconvenient. The aim of present study was to evaluate whether albumin: creatinine ratio (ACR) and urinary albumin concentration (UAC) in different spot urine samples correlate or not with 24-h UAE for screening of microalbuminuria in type 2 diabetic patients. We collected first morning void (FMV), random urine sample (RUS) and 24-h urine, separately on consecutive days from 104 type 2 diabetic patients. ACR and UAC in each spot urine sample compared with 24-h UAE with regard to Pearson correlation coefficient. Pearson’s correlation of albumin: creatinine ratio (ACR) with 24-h UAE was (r = 0.802 and 0.623) in first morning void (FMV) and random urine sample (RUS), respectively. Pearson’s correlation coefficient of urinary albumin concentration (UAC) compared with 24-h UAE was (r = 0.943 and 0.920), in FMV and RUS, respectively, P < 0.01. Results revealed that values in first morning void (FMV) were better correlated with 24-h urinary albumin excretion (UAE), than the values in random urine sample (RUS). We conclude that the first morning void (FMV) may be able to replace 24-h urine collection, preferably urinary albumin concentration (UAC) in the initial screening of microalbuminuria in diabetic patients.  相似文献   
57.
利用流行病学中无金标准的筛检理论构建搜索引擎的评价指标,将用户体验得分和用户判断作为贝叶斯估计的先验信息,通过MCMC技术估算出Google简体中文和百度的灵敏度、特异度和检出率。  相似文献   
58.
基于失屏参数,建立了一个计算金属晶体结合能的新方法,其计算值与文献值符合得很好。  相似文献   
59.
The rapidly developing resistance of cancers to chemotherapy agents and the severe cytotoxicity of such agents to normal cells are major stumbling blocks in current cancer treatments.Most current chemotherapy agents have significant cytotoxicity,which leads to devastating adverse effects and results in a substandard quality of life,including increased daily morbidity and premature mortality.The death receptor of tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)can sidestep p53-dependent pathways to induce tumor cell apoptosis without damaging most normal cells.However,various cancer cells can develop resistance to TRAIL-induced apoptosis via different pathways.Therefore,it is critical to find an efficient TRAIL sensitizer to reverse the resistance of tumor cells to TRAIL,and to reinforce TRAIL’s ability to induce tumor cell apoptosis.In recent years,traditional Chinese medicines and their active ingredients have shown great potential to trigger apoptotic cell death in TRAIL-resistant cancer cell lines.This review aims to collate information about Chinese medicines that can effectively reverse the resistance of tumor cells to TRAIL and enhance TRAIL’s ability to induce apoptosis.We explore the therapeutic potential of TRAIL and provide new ideas for the development of TRAIL therapy and the generation of new anticancer drugs for human cancer treatment.This study involved an extensive review of studies obtained from literature searches of electronic databases such as Google Scholar and PubMed."TRAIL sensitize"and"Chinese medicine"were the search keywords.We then isolated newly published studies on the mechanisms of TRAIL-induced apoptosis.The name of each plant was validated using certified databases such as The Plant List.This study indicates that TRAIL can be combined with different Chinese medicine components through intrinsic or extrinsic pathways to promote cancer cell apoptosis.It also demonstrates that the active ingredients of traditional Chinese medicines enhance the sensitivity of cancer cells to TRAIL-mediated apoptosis.This provides useful information regarding traditional Chinese medicine treatment,the development of TRAIL-based therapies,and the treatment of cancer.  相似文献   
60.
Serum tumor markers may be requested inappropriately by clinicians. In this retrospective study, we aimed to investigate the appropriateness of TM requests in our hospital. Patients in the study were identified from the TM requests for 3 months between June–August 2004, using the laboratory database. A total of 2249 patients (1351 men, 898 women) were included in the study and there were 6570 TM requests. The number of requests were 1050 (16%) for Carbohydrate Antigen 19-9, 993 (15.1%) for Cancer Antigen 125, 941 (14.3%) for Prostate Specific Antigen, 921 (14%) for free PSA, 925 (14.1%) for Cancer Antigen 15-3, 788 (12%) for Alphafetoprotein, 730 (11.1%) for Carcinoembryonic Antigen and 222 (3.4%) for AFP/Human Chorionic Gonadotrophin. Our findings support the idea that for the evidence-based use of TM requests the education of clinical staff is required. Clear clinical guidelines including recommendations about the appropriate use of TM can be useful for this education process. Careful audit studies are also useful to determine the impact of these guidelines on the practice of evidence-based laboratory medicine.  相似文献   
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