神经系统疾病少年儿童患者的脆性X综合征检查与临床诊治研究

目的研究神经疾病少年儿童患者脆性X综合征（fragjle X syndrome,FraX）的细胞遗传学检测和临床诊治特征。方法应用低叶酸培养基，对患神经疾病的18岁以下146例儿童行X染色体脆性部位的检测，对检出的Frax患儿给以叶酸为主辅以营养神经和神经康复的治疗。结果146例就诊患儿检出FraX13例，检出率为8．90％。以补充叶酸为主的综合治疗取得一定疗效，治疗效果与患儿年龄和原发神经疾病有关。结论FraX值得临床重视，早检出、早治疗收效较好。     

SARS冠状病毒棘突蛋白的S1蛋白诱导小鼠产生中和抗体的研究

目的 研究SARS冠状病毒棘突蛋白受体结合部位S1的免疫原性，为SARS的实验诊断和新型疫苗的研究提供依据。方法 用克隆有哺乳动物细胞密码子优化的SARS-CoV S1基因的质粒pcDNA3．1／S1或P-S1Ig转染293T细胞，用细胞的上清液纯化S1蛋白。以pcDNA3．1／S1质粒对BALB／c小鼠进行2次基因免疫，以纯化的S1蛋白进行加强免疫。用ELISA法检测小鼠抗SARS-CoV的特异性IgG抗体，并在Vero E6细胞上做体外中和实验，检测中和抗体。结果 S1蛋白诱导小鼠产生抗SARS-CoV的特异性抗体；1：1499．68稀释的S1蛋白免疫的小鼠血清可保护50％的细胞对1000TCID50的病毒攻击，而阴性对照血清不能保护细胞对病毒的感染。结论 SAPS冠状病毒棘突蛋白受体结合部位S1能有效诱导机体产生具有高效保护作用的中和抗体免疫反应，可望发展成为理想的SARS棘突蛋白亚单位疫苗。     

氟烷和七氟醚对缺血心肌功能和代谢及Ca2+-ATP酶活性的影响

目的: 研究氟烷、七氟醚(1.5MAC)对缺血心肌的影响。方法: 应用离体大鼠心脏Langendorff逆行灌注模型研究氟烷、七氟醚对心肌缺血前心率(HR)、左室舒张末期压力(LVEDP)、左室发展压(LVDP)、左室压力升高速率(+dp/dt)、左室压力下降速率(-dp/dt)和冠脉流量(CF)的影响,测定缺血前、缺血10min、缺血25min3个不同时间的心肌ATP含量、Ca²⁺-ATP酶活性,同时记录缺血间期左室内压的变化情况。结果: 七氟醚显著增加正常离体心脏的CF,氟烷、七氟醚均不同程度地抑制心肌收缩功能和Ca²⁺-ATP酶活性,能够增加正常心肌的能量贮备。缺血10min时,二药能够减缓心肌ATP含量及Ca²⁺-ATP酶活性的下降,氟烷的作用比较明显。缺血间期,氟烷明显推迟缺血性挛缩的起始时间,降低挛缩幅度。结论: 氟烷的抗缺血损伤作用优于七氟醚,延缓缺血期心肌ATP含量及Ca²⁺-ATP酶活性的下降可能是氟烷抗缺血损伤作用的重要机制之一。     

"Waste" follicular aspirate from fertility treatment--a potential source of human germline stem cells?

Fertility clinics worldwide routinely produce a large volume of 'waste' follicular aspirate, which is potentially an abundant source of immature ovarian follicles. Current attempts to cultivate these further in vitro to yield viable mature oocytes for fertility treatment have not yet achieved much success. Instead, recent lines of evidence have emerged that are suggestive of a potential stem cell niche within such immature ovarian follicles. The recent discovery of follicular renewal and putative germ-line stem cells within the postnatal mammalian ovary shook the foundations of reproductive biology by challenging the established dogma that mammalian females lose the capacity for germ cell renewal during fetal life, such that a fixed reserve of germ cells (oocytes) enclosed within follicles is endowed at birth. More intriguingly, another recent study in the Drosophila model provided compelling evidence that somatic progenies (nurse cells) of germ-line stem cells had the ability to revert back to the stem-cell-like state. This introduces the exciting possibility that within the mammalian ovarian follicle, similar somatic progenies of germ-line stem cells may also possess a greater intrinsic ability to revert back into functional stem cells. If this is the case, then a favored candidate would be the cumulus/granulosa of immature ovarian follicles, since such cells are true homologues of nurse cells found within the Drosophila ovary. The successful elucidation of a human germ-line stem cell niche within immature ovarian follicles is likely to have huge ramifications in stem cell biology and regenerative medicine.     

中国汉族人与美国高加索白人膝关节几何形态的比较

背景:有研究显示中国人膝关节胫骨近端前后径和横径均小于美国高加索人,所以在膝关节形态学方面存在一定差异,因此常发生进口假体系统应用于国人后出现匹配度不高的现象。目的:测量中国人和美国人股骨远端、胫骨近端的几何形态学参数,比较其差异。方法:选择北京清华长庚医院骨科拟行前交叉韧带重建的中国汉族患者50例,以及美国匹兹堡大学运动医学中心拟行前交叉韧带重建的高加索白人后裔患者40例,对90例受试者膝关节进行CT扫描,使用AW Volume Share 5软件进行三维重建,利用Geomagic软件对胫骨近端和股骨远端的各项参数进行测量。结果与结论:①股骨近端测量参数中,中国人的外侧胫骨平台内外径小于美国人(P=0.027),外侧胫骨平台后倾角大于美国人(P<0.05);两组间胫骨平台内外径、内侧胫骨平台外径、内侧胫骨平台前后径、外侧胫骨平台前后径与内侧胫骨平台后倾角比较差异均无显著性意义(P>0.05);②股骨远端测量参数中,中国人的股骨远端横径、外侧髁内外径、内侧髁前后径、外侧髁前后径及髁间窝高度均小于美国人(P<0.05),股骨外翻角大于美国人(P<0.05);两组间内侧髁内外径、髁间窝宽度及滑车沟宽度比较差异无显著性意义(P>0.05);③结果表明,中国人与美国人在膝关节形态学的多个参数存在差异,有必要针对中国人设计更为个体化的膝关节假体。     

Towards practical soft X-ray spectromicroscopy of biomaterials

Scanning transmission X-ray microscopy (STXM) is being developed as a new tool to study the surface chemical morphology and biointeractions of candidate biomaterials with emphasis on blood compatible polymers. STXM is a synchrotron based technique which provides quantitative chemical mapping at a spatial resolution of 50 nm. Chemical speciation is provided by the near edge X-ray absorption spectral (NEXAFS) signal. We show that STXM can detect proteins on soft X-ray transparent polymer thin films with monolayer sensitivity. Of great significance is the fact that measurements can be made in situ, i.e. in the presence of an overlayer of the protein solution. The strengths, limitations and future potential of STXM for studies of biomaterials are discussed.     

Evolutionary computing for knowledge discovery in medical diagnosis

One of the major challenges in medical domain is the extraction of comprehensible knowledge from medical diagnosis data. In this paper, a two-phase hybrid evolutionary classification technique is proposed to extract classification rules that can be used in clinical practice for better understanding and prevention of unwanted medical events. In the first phase, a hybrid evolutionary algorithm (EA) is utilized to confine the search space by evolving a pool of good candidate rules, e.g. genetic programming (GP) is applied to evolve nominal attributes for free structured rules and genetic algorithm (GA) is used to optimize the numeric attributes for concise classification rules without the need of discretization. These candidate rules are then used in the second phase to optimize the order and number of rules in the evolution for forming accurate and comprehensible rule sets. The proposed evolutionary classifier (EvoC) is validated upon hepatitis and breast cancer datasets obtained from the UCI machine-learning repository. Simulation results show that the evolutionary classifier produces comprehensible rules and good classification accuracy for the medical datasets. Results obtained from t-tests further justify its robustness and invariance to random partition of datasets.     

基于EGFR介导的信号通路探讨中药活性成分抗肿瘤研究进展

在我国恶性肿瘤已经成为最主要的死亡原因,近年来,恶性肿瘤发病率和死亡率逐年增高,严重威胁人民的生命健康,癌症负担不断增加。恶性肿瘤的治疗,目前主要是以手术为主的外科治疗、放射治疗和以细胞增殖抑制药物为代表的内科治疗,但有很多治疗局限性且治疗相关不良反应较大。而随着生物科学技术的发展,随着人们对肿瘤微环境、免疫学、细胞生物学和分子生物学等领域的研究,抗肿瘤治疗的热点已经转向高效低毒、目标明确的靶向治疗。表皮生长因子受体（EGFR）在细胞增殖、存活、分化、迁移、炎症和基质稳态等许多细胞过程中发挥着重要作用。EGFR通过多种方式促进肿瘤的生长、增殖及转移。中医药在恶性肿瘤的综合治疗中具有独特疗效,中药抗肿瘤具有多成分、多靶点、多途径的特点,能够发挥增效减毒、延长生命、提高生存质量的作用。目前发现的许多中药及其有效成分具有抗肿瘤作用,其机制与抑制EGFR信号传导通路有关。中药靶向抑制EGFR可以促进肿瘤细胞的凋亡和自噬,抑制肿瘤细胞的增殖和转移,延缓肿瘤的进展,是抑制肿瘤的潜在靶点。该文总结了EGFR信号传导通路和肿瘤发生发展的关系,并分析中药及其有效成分通过调节EGFR信号通路抗肿瘤的作用方...