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991.
雷娜  雷钧茜  吴辉  石崇景  徐月阳 《生物磁学》2011,(15):2976-2978
为适应目前医学事业发展的需要,医学生的临床思维与临床技能的培养至关重要。在教学中,应不断提高教师自身的业务水平和自身素质,给予学生适当引导和启发,采取灵活多样的教学方式,并鼓励学生学会独立思考能力,激发学生的主动性和创造性,同时理论与实践相结合,推出模拟教学,由此激发学生的学习兴趣;并通过病例的采集归纳和整理,加强基本功的训练。从而提高学生临床思维能力与标准实践技能。  相似文献   
992.
刘倩  周莉  何晓凤 《生物磁学》2011,(7):1333-1335
成人先天性髋关节发育不良是一种髋臼先天性发育缺陷的疾病,长期发展会形成髋关节半脱位、脱位,最终甚至可能出现股骨头坏死等严重合并症。对于早期患者目前主要采用髋臼旋转截骨手术治疗,而晚期出现股骨头脱位及坏死则只能通过全髋关节置换进行治疗。不论哪种手术方式,围手术期的护理对于患者的健康恢复都有着非常重要的意义。  相似文献   
993.
赵谦  杜娟 《生物磁学》2011,(18):3565-3568
DPPA2(Developmental pluripotency.associatedgene2)是近年来发现的一种在多能性细胞和某些癌组织中特意表达的基因。它与早期胚胎发育密切相关,参与维持胚胎干细胞的多能性及自我更新,还在体细胞重编程为多能性诱导干细胞的过程中发挥了作用。此外,它还是一种新的肿瘤抗原,有望成为某些恶性肿瘤的特异性免疫治疗新靶点。本文就DPPA2的结构、功能,以及它与胚胎发育、恶性肿瘤、体细胞重编程的关系等方面的研究进展做一综述。  相似文献   
994.
随着生物医学技术、计算机技术、物理化学技术的迅速发展,临床医学对检验医学提出了更高的要求。作为实验室工作人员,在保证结果准确的基础上,还应对临床医生及病人提出的疑问给予合理、正确地解释。此外,还应该具备和临床医生进行交流,以及合理处理病人投诉的能力。五年制检验医学本科生是检验医学的主力军,培养高素质的检验医学本科生,对检验医学的发展将起关键性作用。  相似文献   
995.
利用乳腺生物反应器高效地表达重组人乳清白蛋白,但是目标产物分离纯化的难度较大。通过分子模拟计算比较待分离原料中主要蛋白组分的物化性质,包括表面电势和表面疏水性,在此基础上设计了高分辨率、快速的分离纯化工艺。通过硫酸铵沉淀的正交试验条件优化,有效地去除了干扰层析精制过程的IgG杂质,提高了后续疏水层析的稳定性,从而成功地分离开目标蛋白及与其同源的牛乳清白蛋白杂质,得到纯度>95%的rHLA纯品,工艺回收率48.6%。乳糖合成活性和圆二色谱检测结果表明,纯化rHLA具有调节β-1,4-半乳糖苷转移酶活性和天然的空间结构。  相似文献   
996.
The complexity and dynamics of microbial metagenomes may be evaluated by genome size, gene duplication and the disruption rate between lineages. In this study, we pyrosequenced the metagenomes of microbes obtained from the brine and sediment of a deep-sea brine pool in the Red Sea to explore the possible genomic adaptations of the microbes in response to environmental changes. The microbes from the brine and sediments (both surface and deep layers) of the Atlantis II Deep brine pool had similar communities whereas the effective genome size varied from 7.4 Mb in the brine to more than 9 Mb in the sediment. This genome expansion in the sediment samples was due to gene duplication as evidenced by enrichment of the homologs. The duplicated genes were highly disrupted, on average by 47.6% and 70% for the surface and deep layers of the Atlantis II Deep sediment samples, respectively. The disruptive effects appeared to be mainly due to point mutations and frameshifts. In contrast, the homologs from the Atlantis II Deep brine sample were highly conserved and they maintained relatively small copy numbers. Likely, the adaptation of the microbes in the sediments was coupled with pseudogenizations and possibly functional diversifications of the paralogs in the expanded genomes. The maintenance of the pseudogenes in the large genomes is discussed.  相似文献   
997.

Background

The Beijing family is a successful group of M. tuberculosis strains, often associated with drug resistance and widely distributed throughout the world. Polymorphic genetic markers have been used to type particular M. tuberculosis strains. We recently identified a group of polymorphic DNA repair replication and recombination (3R) genes. It was shown that evolution of M. tuberculosis complex strains can be studied using 3R SNPs and a high-resolution tool for strain discrimination was developed. Here we investigated the genetic diversity and propose a phylogeny for Beijing strains by analyzing polymorphisms in 3R genes.

Methodology/Principal Findings

A group of 3R genes was sequenced in a collection of Beijing strains from different geographic origins. Sequence analysis and comparison with the ones of non-Beijing strains identified several SNPs. These SNPs were used to type a larger collection of Beijing strains and allowed identification of 26 different sequence types for which a phylogeny was constructed. Phylogenetic relationships established by sequence types were in agreement with evolutionary pathways suggested by other genetic markers, such as Large Sequence Polymorphisms (LSPs). A recent Beijing genotype (Bmyc10), which included 60% of strains from distinct parts of the world, appeared to be predominant.

Conclusions/Significance

We found SNPs in 3R genes associated with the Beijing family, which enabled discrimination of different groups and the proposal of a phylogeny. The Beijing family can be divided into different groups characterized by particular genetic polymorphisms that may reflect pathogenic features. These SNPs are new, potential genetic markers that may contribute to better understand the success of the Beijing family.  相似文献   
998.
999.
Ma N  Liu Y  Fu XM  Li N  Wang CX  Zhang H  Qian RB  Xu HS  Hu X  Zhang DR 《PloS one》2011,6(1):e16560

Background

The default mode network (DMN) is a set of brain regions that exhibit synchronized low frequency oscillations at resting-state, and is believed to be relevant to attention and self-monitoring. As the anterior cingulate cortex and hippocampus are impaired in drug addiction and meanwhile are parts of the DMN, the present study examined addiction-related alteration of functional connectivity of the DMN.

Methodology

Resting-state functional magnetic resonance imaging data of chronic heroin users (14 males, age: 30.1±5.3 years, range from 22 to 39 years) and non-addicted controls (13 males, age: 29.8±7.2 years, range from 20 to 39 years) were investigated with independent component analysis to address their functional connectivity of the DMN.

Principal Findings

Compared with controls, heroin users showed increased functional connectivity in right hippocampus and decreased functional connectivity in right dorsal anterior cingulate cortex and left caudate in the DMN.

Conclusions

These findings suggest drug addicts'' abnormal functional organization of the DMN, and are discussed as addiction-related abnormally increased memory processing but diminished cognitive control related to attention and self-monitoring, which may underlie the hypersensitivity toward drug related cues but weakened strength of cognitive control in the state of addiction.  相似文献   
1000.
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