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171.
In 2006, the Indian Council of Medical Research (ICMR) published its ‘Ethical guidelines for Biomedical Research on human participants’. The intention was to translate international ethical standards into locally and culturally appropriate norms and values to help biomedical researchers in India to conduct ethical research and thereby safeguard the interest of human subjects. Unfortunately, it is apparent that the guideline is not fit for purpose. In addition to problems with the structure and clarity of the guidelines, there are several serious omissions and contradictions in the recommendations. In this paper, we take a close look at the two key chapters and highlight some of the striking flaws in this important document. We conclude that ethics committees and national authorities should not lose sight of international ethical standards while incorporating local reality and cultural and social values, as focusing too much on the local context could compromise the safety of human subjects in biomedical research, particularly in India. 相似文献
172.
转基因树木研究现状及发展趋势 总被引:3,自引:0,他引:3
通过基因工程技术将外源基因到树木基因组弥补了其传统育种手段周期长、过程繁琐、性状难以人为控制的缺点.在过去20年,树木转基因研究取得了令人鼓舞的成果,选育出多种携带外源基因的树木,并经过了限制性田间试验.国外开展树木转基因研究先于国内,在抗除草剂、抗虫、降低木质素等方面取得了显著进展,同时开展了转基因表达稳定性和安全性方面的研究.本文综合论述了近年来国内外树木转基因工作研究进展.就各国转基因树木种植概况、遗传性状改良方向、田间试验情况进行了介绍和总结,分析了存在的问题和未来发展的趋势.以期为我国从事林木基因工程研究的科研工作者以及政府决策部门提供借鉴,以促进我国树木基因工程的研究和发展. 相似文献
173.
In the design of clinical trials, the sample size for the trial is traditionally calculated from estimates of parameters of interest, such as the mean treatment effect, which can often be inaccurate. However, recalculation of the sample size based on an estimate of the parameter of interest that uses accumulating data from the trial can lead to inflation of the overall Type I error rate of the trial. The self-designing method of Fisher, also known as the variance-spending method, allows the use of all accumulating data in a sequential trial (including the estimated treatment effect) in determining the sample size for the next stage of the trial without inflating the Type I error rate. We propose a self-designing group sequential procedure to minimize the expected total cost of a trial. Cost is an important parameter to consider in the statistical design of clinical trials due to limited financial resources. Using Bayesian decision theory on the accumulating data, the design specifies sequentially the optimal sample size and proportion of the test statistic's variance needed for each stage of a trial to minimize the expected cost of the trial. The optimality is with respect to a prior distribution on the parameter of interest. Results are presented for a simple two-stage trial. This method can extend to nonmonetary costs, such as ethical costs or quality-adjusted life years. 相似文献
174.
BiTEs(bispecificTcellengagers)是一种以T细胞作为效应细胞的双特异性单链抗体 ,它具有两个抗原结合臂 ,可以同时和T细胞及靶细胞结合 ,并激活细胞毒性T细胞杀伤病变细胞。和其它双特异性抗体相比 ,BiTEs的分子柔韧性更好 ,能更好地促进CD3复合体和肿瘤靶标的连接 ,并且它不受T细胞受体和靶细胞上MHCⅠ类分子的约束 ,不需要共刺激分子的参与 ,是一种极具应用潜力的抗体形式。就BiTEs的结构、作用机理及其在肿瘤临床上的应用前景几个方面做一综述。 相似文献
175.
It is of interest to document the views of medical professionals on the application of artificial intelligence (using known data for the prediction of unknown events) in clinical trials using a web survery with a structured questionnaire from 377 subjects. The questionnaire contained 17 statements which were categorised into awareness (1,2 statements), perception (3-10 statements) and opinion (11-17 statements). The data obtained was compared between the subjects using two tailed Fisher''s exact test with p-value <0.05 for data significance analysis. Data shows that majority of professionals have possitive views on the application of artificial intelligence in clinical trials. This will accelarrate the drug evaluation process. However, the use of emerging tools such as AI will not replace human subjects in this context. 相似文献
176.
目的:评价非索非那定治疗变应性鼻炎的疗效及其安全性。方法:计算机检索SCI,Pubmed,Elsevier,Cochrane图书馆,知网,万方数据库,维普数据库中关于非索非那定治疗变应性鼻炎的随机对照试验,同时追索纳入文献的参考文献。检索年限均从建库检索到2013年12月。由两名评价员独立筛查文献,对纳入的文献进行质量评价并提取文献,对符合质量标准的随机对照试验(RCT)进行Meta分析,比较非索非那定组和安慰剂组鼻部症状评分、血清中白三烯浓度、生活质量评价、症状改善率和安全性评估。统计学分析采用RevMan5.2软件。结果:共纳入9个RCT。患者口服非索非那定片30mg/d,120mg/d,180mg/d后可有效改善变应性鼻炎患者的症状,可降低患者鼻部症状评分、血清中白三烯浓度;有效提高生活质量,降低患者总的生活质量评分(P均〈0.05)。非索非那定不良反应的发生率与安慰剂组相似,不良反应发生率差异无统计学意义(P〉0.05)。结论:患者口服非索非那定片30mg/d,120mg/d,180mg/d后可以有效缓解患者的症状,改善患者的生活质量,且不良反应发生率与对照组相近。基于非索非那定较好的有效性和安全性,故可以广泛应用于临床,更加有效的缓解变应性鼻炎患者的症状。 相似文献
177.
William R. Jeck Joel Parker Craig C. Carson Janiel M. Shields Maria J. Sambade Eldon C. Peters Christin E. Burd Nancy E. Thomas Derek Y. Chiang Wenjin Liu David A. Eberhard David Ollila Juneko Grilley‐Olson Stergios Moschos D. Neil Hayes Norman E. Sharpless 《Pigment cell & melanoma research》2014,27(4):653-663
Somatic sequencing of cancers has produced new insight into tumorigenesis, tumor heterogeneity, and disease progression, but the vast majority of genetic events identified are of indeterminate clinical significance. Here, we describe a NextGen sequencing approach to fully analyzing 248 genes, including all those of known clinical significance in melanoma. This strategy features solution capture of DNA followed by multiplexed, high‐throughput sequencing and was evaluated in 31 melanoma cell lines and 18 tumor tissues from patients with metastatic melanoma. Mutations in melanoma cell lines correlated with their sensitivity to corresponding small molecule inhibitors, confirming, for example, lapatinib sensitivity in ERBB4 mutant lines and identifying a novel activating mutation of BRAF. The latter event would not have been identified by clinical sequencing and was associated with responsiveness to a BRAF kinase inhibitor. This approach identified focal copy number changes of PTEN not found by standard methods, such as comparative genomic hybridization (CGH). Actionable mutations were found in 89% of the tumor tissues analyzed, 56% of which would not be identified by standard‐of‐care approaches. This work shows that targeted sequencing is an attractive approach for clinical use in melanoma. 相似文献
178.
179.
《Journal of Asia》2020,23(4):1023-1029
Aphids are among the most destructive phytophagous pests of host plants, because of their rapid reproduction, parthenogenesis, extensive crop damage, and the transmission of many plant viruses. Since lady beetles are important predatory natural enemies of aphids, developing lady beetle attractants to increase their field abundance is vital for aphid control. Floral volatiles and other semiochemicals are reportedly attractive to lady beetles. In this research, a total of 58 floral volatiles were tested by Y-tube olfactometer assays, among which 29 were highly attractive to both Harmonia axyridis (Coleoptera: Coccinellidae) and Coccinella septempunctata (Coleoptera: Coccinellidae). Meanwhile, the results of wind tunnel trials showed that only isoamyl acetate, α-humulene, trans-3-hexen-1-ol, methyl salicylate, and β-pinene lure these two species. Thereafter, 15 semiochemicals from pests, natural enemies, and pest-infested crops were mixed with the selected floral volatiles, to determine optimum formulations for attracting lady beetles through wind tunnels and further field trials. Eventually, formulas (1) α-humulene: β-pinene: methyl salicylate: trans-3-hexen-1-ol = 1:3:3:10; (5) α-humulene: β-pinene: methyl salicylate:1-nonanal = 1:3:3:10; (8) α-humulene: β-pinene: methyl salicylate: indole = 1:3:3:10 (1, 5, and 8 are labels used for the various formulations in field trials) were successfully verified to be attractive to lady beetles in both pumpkin and wheat fields. These formulations will be of great significance in developing integrated pest management strategies for aphid control. 相似文献
180.
目的评价人心脏型脂肪酸结合蛋白(H-FABP)检测试剂盒(胶体金法)在急性心肌梗死(AMI)诊断中的价值。方法采用平行、盲法、对照的对比试验设计,比较其试验产品和对比产品对诊断AMI的敏感性、特异性、准确性。结果共测定240份临床血液标本。试验产品和对比产品的阳性符合率为100%,阴性符合率为96.15%,总符合率为97.92%。对比产品和试验产品结果不一致的5例标本以临床诊断结果为标准进行验证后,试验产品与临床诊断结果的阳性符合率为100%,总符合率为100%。采用Kappa检验考核两种产品测定结果的一致性,Kappa指数为0.958。经McNamara's test分析,两产品之间无差异,χ2=3.20,P>0.05。结论试验产品显示出较好的诊断价值,可以作为AMI早期诊断标志物,试验产品与对比产品等效。 相似文献