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211.
Serum protein fingerprinting coupled with artificial neural network distinguishes glioma from healthy population or brain benign tumor 总被引:6,自引:0,他引:6
To screen and evaluate protein biomarkers for the detection of gliomas (Astrocytoma grade Ⅰ-Ⅳ) from healthy individuals and gliomas from brain benign tumors by using surface enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS) coupled with an artificial neural network (ANN) algorithm. SELDI-TOF-MS protein fingerprinting of serum from 105 brain tumor patients and healthy individuals, included 28 patients with glioma (Astrocytoma Ⅰ-Ⅳ), 37 patients with brain benign tumor, and 40 age-matched healthy individuals. Two thirds of the total samples of every compared pair as training set were used to set up discriminating patterns, and one third of total samples of every compared pair as test set were used to cross-validate; simultaneously, discriminate-cluster analysis derived SPSS 10.0 software was used to compare Astrocytoma grade Ⅰ-Ⅱ with grade Ⅲ-Ⅳ ones. An accuracy of 95.7%, sensitivity of 88.9%, specificity of 100%, positive predictive value of 90% and negative predictive value of 100% were obtained in a blinded test set comparing gliomas patients with healthy individuals; an accuracy of 86.4%, sensitivity of 88.9%, specificity of 84.6%, positive predictive value of 90% and negative predictive value of 85.7% were obtained when patient's gliomas was compared with benign brain tumor. Total accuracy of 85.7%, accuracy of grade Ⅰ-Ⅱ Astrocytoma was 86.7%, accuracy ofⅢ-Ⅳ Astrocytoma was 84.6% were obtained when grade Ⅰ-Ⅱ Astrocytoma was compared with grade Ⅲ-Ⅳ ones (discriminant analysis). SELDI-TOF-MS combined with bioinformatics tools, could greatly facilitate the discovery of better biomarkers. The high sensitivity and specificity achieved by the use of selected biomarkers showed great potential application for the discrimination of gliomas patients from healthy individuals and glioma from brain benign tumors. 相似文献
212.
大学,这个无数人向往的象牙塔。大学是智慧的象征,是精神的家园,是令人向往和憧憬的圣地。从高中走进大学,就如同沿着小溪和江河蛋糕进了大海。请关注本期特别策划——我的大学! 相似文献
213.
网络正在以前所未有的速度进入我们的工作和生活,深刻地影响着人们的生活、学习方式。In-ternet的快速发展为我们提供了大量的学习资源。在数字时代,学习、工作和生活紧密地融合在一起。学习成为人类生存的先决条件。丰富的网络资源建构了一个活跃的学习环境。基于资源的学习正在成为一种重要的学习方式,它能够满足不同学生的需要,使学习者得到提高。一、资源型学习的内涵资源型学习是学生根据学习任务,从丰富的学习环境和学习资源中,在教师激发与引导下的正式或非正式实践活动,将检索和探求所获得的信息组 相似文献
214.
To investigate the effects of salt concentration and freeze-thaw (FT) on the first hydration shell of Zn2+ ions in Zn(NO3)2 aqueous solutions, extended X-ray absorption fine structure (EXAFS) spectroscopy was used to examine Zn K-edge EXAFS spectra of Zn(NO3)2 aqueous solutions with various concentrations before and after FT treatment. The influences of salt concentration and freeze-thaw on the structural parameters of the first hydration shell of Zn2+ ions, including hydration number, Zn-O distance and thermal disorder, were analyzed. The results show that Zn2+ ions have 3.2―6.8 nearest oxygen neighbors with the Zn-O distance being 0.202―0.207 nm. In highly concen-trated solutions, Zn2+ ions are hydrated with four water molecules in a tetrahedral form. The dilution of Zn(NO3)2 aqueous solutions increases the number of water molecules in the first hydration shell of Zn2+ ions to six with their octahedral arrangement. Both the hydration number in the first hydration shell of Zn2+ ions and the degree of thermal disorder increase when the FT treatment is operated in Zn(NO3)2 aqueous solutions. 相似文献
215.
当前,部分学校片面地追求高考成绩,在教学中压缩了美术、音乐等非高考科目的课时。这不但有违新课程改革的教学理念,而且扼杀了学生学习美术的兴趣爱好。笔者多年从事美术教学工作,收获了几点体会,望与大家共勉。 相似文献
216.
Karami R Hosseini M Khodabandehloo F Khatami L Taiarani Z 《Journal of Zhejiang University. Science. B》2011,12(12):1016-1023
Objective
The roles of gonadal hormones and nitric oxide (NO) on the analgesic effects of morphine, tolerance to morphine, and their interactions have been widely investigated. In the present study, the effect of l-arginine (an NO precursor) on morphine tolerance in sham and ovariectomized (OVX) female mice was investigated. 相似文献217.
In this quasi-experimental study, we describe the effect of showing dissection videos on first-year medical students' performance in terms of test scores during a gross anatomy course. We also surveyed students' perception regarding the showing of dissection videos. Two hundred eighty-seven first-year medical students at Rawalpindi Medical College in Pakistan, divided into two groups, dissected one limb in first term and switched over to the other limb in the second term. During the second term, instruction was supplemented by dissection videos. Second-term anatomy examination marks were compared with first-term scores and with results from first-year medical students in previous years. Multiple linear regression analysis was performed, with term scores (continuous, 0-200) as the dependent variable. Students shown dissection videos scored 1.26 marks higher than those not shown. The relationship was not statistically significant (95% CI: -1.11, 3.70; P = 0.314). Ninety-three percent of students favored regular inclusion of dissection videos in curriculum, and 50% termed it the best source for learning gross anatomy. Seventy-six percent of students did not perform regular cadaver dissection. The most frequent reason cited for not performing regular dissection was high student-cadaver ratio. Dissection videos did not improve performance on final examination scores; however, students favored their use. 相似文献
218.
Yi K Li D Park WS Park KH Shim TT Kwern O Kim JY 《Journal of deaf studies and deaf education》2011,16(3):375-391
Individuals' relative awareness of thematic and taxonomic relations is influenced by factors such as language and background knowledge. Relatively weak in Korean language skills and also having relatively limited social opportunities, Korean deaf adolescents might be different from hearing adolescents in how they make decisions in taxonomically and thematically associated entities represented by pictures and words. Experiment 1 indicated that deaf adolescents had longer reaction times than hearing adolescents in a forced-choice decision-making task. Both deaf and hearing adolescents had shorter reaction times and higher accuracies with pictures than with words, but deaf adolescents' differences were bigger than those of hearing adolescents. Experiment 2 further showed that deaf adolescents had lower accuracies than hearing adolescents in a priming task of living-nonliving categorization. Both deaf and hearing adolescents had shorter reaction times with taxonomic than with thematic categories, but deaf adolescents' difference was bigger than that of hearing adolescents. In conclusion, Korean deaf adolescents were aware of thematic and taxonomic relations less than hearing adolescents in general. They were more likely than hearing adolescents to show the advantage of pictures over words in their performance in conceptual activities and to prefer taxonomic to thematic associations for written words in Experiment 2. 相似文献
219.
在中国,有些老年人讳疾忌医,得病后害怕去医院看医生,就连像“病”和“癌”这样的字眼儿,也非常忌讳听到。而类似在有生之年立下遗嘱或提前安排身后之事这样的事,就更不要提了。人的年龄越大,心理承受能力越弱,也就更害怕谈论疾病和触碰生死这条红线。对于这一点,定居日本多年的兰州人赵林深有体会。他在老家的母亲腹痛两年都死活不愿去医院就诊,用她的话来说,如果医生告诉她患了绝症,那不是更吓人吗?不知道结果,她反而不会感到害怕。不过赵林眼中的日本老人却不是这样。在日本老人看来,疾病和死亡并不是什么恐怖的事情,而是生命走至尽头的必经之路。正视死亡、坦然面对,在日本老人中是非常普遍寻常的生死观。 相似文献
220.
小学科学的主要学习方式是学生的实验和探究活动,其目的不仅要学生在积极的实验和探究活动中领悟教材的内容,还得养成良好的实验和探究的习惯,培养科学的素养。实验老师创新实验教学方法,把解决实验教学难点和调动学生积极性创造性相结合,实验课教学就能够取得很好的成效。 相似文献