胚胎干细胞应用及其伦理学问题

目的:介绍胚胎干细胞的研究成果及其可能的临床应用,同时对胚胎干细胞应用中的伦理学问题进行探讨。资料来源:应用计算机检索Medline1996-01/2006-12与胚胎干细胞相关的文章,检索词为“embryonicstemcells,application,morality”,限定文献语种为“English”;同时检索万方数据库2000-01/2006-12相关文章,检索词为“胚胎干细胞,应用,伦理”,限定文献语种为中文。资料选择:共检索到相关文献290条,进一步查找全文,选择与胚胎干细胞可能的应用、以及与其应用相关的论理学讨论相关的文章,筛除明显重复文献,最后纳入30条文献进行综述。资料提炼:30条文献中论述胚胎干细胞可能的应用文章有18篇,探讨胚胎干细胞应用中的伦理学问题的12篇。资料综合:①目前认为,胚胎干细胞在人类医学方面可能应用于癌症、心血管疾病、神经系统疾病、糖尿病、肝脏疾病、烧伤和创伤、骨和软骨疾病等的治疗,胚胎干细胞还能用于器官组织移植、基因治疗和基因功能分析以及新药研制和开发等领域。②国内已经规定用于研究的人胚胎干细胞只能通过4种方式获得:体外受精时多余的配子或囊胚(14d内的胚胎);自然或自愿选择流产的胎儿细胞;体细胞核移植技术所获得的囊胚和单性分裂囊胚;自愿捐献的生殖细胞。同时禁止进行生殖性克隆人的任何研究。结论:胚胎干细胞对临床疾病治疗的应用价值不可估量,在积极鼓励开展胚胎干细胞研究的同时,应加强管理,制定出相应的管理法规和制度,促进胚胎干细胞研究向健康和正确的方向发展。     

噪声条件下听力测试的应用

噪声条件下听力测试(hearing in noise test,HINT)是在安静和噪声条件下测试语句识别阈(reception thresholdsfor sentences,RTS)的一项临床听力测试方法[1].目     

Cyclical vomiting syndrome: Recognition,assessment and management

Cyclical vomiting syndrome (CVS) is a functional, debilitating disorder of childhood frequently leading to hospitalization. Affected children usually experience a stereotypical pattern of vomiting though it may vary between different individuals. The vomiting is intense often bilious, and accompanied by disabling nausea. Identifiable precipitating factors for CVS include psychosocial stressors, infections, lack of sleep and occasionally even food triggers. Often, it may be difficult to distinguish episodes of CVS from other causes of acute abdomen and altered consciousness. Thus, the diagnosis of CVS remains largely one of exclusion. Investigations routinely done during the work-up of a child with suspected CVS include both blood and imaging modalities. Plasma lactate, ammonia, amino acid and acylcarnitine profiles as well as urine organic acid profile are indicated to exclude inborn errors of metabolism. The treatment remains challenging and targeted at prevention or shortening of the attacks and can be considered as abortive, supportive and prophylactic. Use of non-pharmacological therapy is also part of the management of CVS. The prognosis of CVS is variable. More insight into the pathogenesis of this disorder as well as role of non-pharmacological therapy is needed.     

浙江省4个地区60岁以上老人生活满意度的调查

目的:了解浙江省农村老年人生活满意度的现状及其有关影响因素。方法:于2005-07/10随机抽取浙江省乐清市北白象镇、白石镇、大荆镇,建德市的莲花镇及杭州下沙区和余杭区内能回答调查问卷的各项内容,同意参与该项调查的60岁以上老年人430名为调查对象。应用WHO推荐的生活满意度指数A量表,一般状况调查表,最满意和最不满意的事情调查表进行入户问卷调查。生活满意度指数A量表,包括20个项目,其中12个条目反映正性情感,8个条目反映负性情感。每项最高分为2分,总分最高分为40分。评分越高,生活质量越佳。一般状况调查表包括姓名、年龄、性别、职业、文化程度、婚姻、健康状况、医疗费用来源、住址和联系电话。结果:共发放问卷430份,收回有效问卷389份。①389名老年人生活满意度评分为25.8±7.2,与正常值(12.4±4.4)比较,差异有显著性意义(P<0.05)。②经多个独立样本的非参数检验,老年人的生活满意度评分性别差异无显著性(P>0.05),而在年龄、婚姻、文化程度、健康状况、职业、医疗费用来源和所在地区维度差异有显著性(P≤0.05)。③313人对“最满意和最不满意的事情”项目进行了回答,老年人最满意的事是“生活条件改善”和“家庭关系和睦”,有195人,占62.3%,最不满意的事主要是“家庭不和睦”(17.4%)、“社会发展不佳”(14.8%)、“身体状况差”(14.2%)、“生活条件差”(10.3%)。结论:浙江省农村老年人生活满意度较高,年龄、婚姻、文化程度、健康状况、职业、医疗费用来源、地区差异对老年人生活满意度有重要影响。     

大连市7～18岁学生1995～2005年肥胖流行情况分析:以皮褶厚度计算体脂含量

目的:采用皮褶厚度计算体脂含量的方法,了解大连学生超重和肥胖流行现状和流行趋势,为青少年生长发育研究、改善学生营养状况和制定学生肥胖防治措施提供依据。方法:①2005-05/06采用简单随机抽样原则,抽取大连市区的出生并生长的7～18岁汉族学生2474名,其中男生1244名,女生1230名。采用国际通用的人体测量学方法测量纳入学生的肱三头肌和肩胛下角部的皮褶厚度,并通过皮褶厚度推算体密度,计算全身体脂含量,再利用体脂含量判断肥胖并计算发生率。并将上述结果与1995年大连市内7～17岁汉族学生1190名和2000年大连市内7～18岁汉族学生1275名肥胖调查结果进行对比分析。②性别差异比较使用大样本的u检验。结果:2005年参与调查的2474名学生均进入结果分析。①学生体脂含量女生随年龄的增长而增加,男生则在11岁时达高峰后呈逐渐下降趋势,生长曲线男女无交叉现象。而且相同年龄段的体脂含量均是女生高于男生,并且除10～13岁年龄组外,其他年龄组差异均有显著性意义(u>1.96,2.58,P<0.05～0.01)。②与1995年调查结果比较,学生体脂含量10年来有较大程度增长,10年平均增长男女生分别为6.31%和4.47%。③学生2000年超重、轻度肥胖和中重度肥胖的发生率男生分别为14.3%,11.1%和7.9%,女生分别为11.0%,7.2%和2.8%。2005年超重、轻度肥胖和中重度肥胖的发生率男生分别为18.0%、11.6%和19.9%,女生分别为15.0%,10.2%和11.7%。结论:①2005年青春期后学生体脂含量有性别差异。②大连学生10年来体脂含量有较大程度的增长,并有继续增加的趋势。③大连学生5年间超重、轻度肥胖和中重度肥胖的发生率增加明显。     

间充质干细胞的免疫调节作用

目的:间充质干细胞因具有多向分化潜能及植入体内无排斥反应等特性而被广泛应用于医学领域。文章就间充质干细胞的生物学特性、免疫原性、免疫调节作用及其应用进行综述。资料来源:应用计算机检索PUBMED1994-02/2007-03期间的相关文章,检索词为“mesenchymal stem cell,immune”,并限定文章语言种类为English。同时计算机检索中国期刊全文数据库2004-01/2007-02期间的相关文章,检索词为“间充质干细胞,免疫”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:文章所述内容应与间充质干细胞的免疫调节研究相关。排除标准:重复研究。资料提炼:共收集到152篇相关文献,56篇文献符合纳入标准,排除的96篇文献为内容陈旧或重复。文章选择符合纳入标准的31篇文献,分别涉及间充质干细胞的生物学特性、免疫原性、免疫调节作用(抑制T细胞的增殖、移植物和宿主的免疫反应)及应用等内容。资料综合:间充质干细胞可以从哺乳动物成体骨髓、脂肪组织、肾脏、皮肤及相应胎儿组织中分离获得,具有向成骨细胞、成软骨细胞、脂肪细胞、神经细胞等多种组织细胞分化的潜能。此外其在免疫反应中可逃避免疫识别、抑制免疫反应的特性引起医学研究领域的广泛关注。间充质干细胞通过与免疫细胞(包括抗原递呈细胞、淋巴细胞、自然杀伤细胞)的相互作用降低免疫原性,调节免疫反应活性。间充质干细胞用于细胞治疗在心脏功能修复、骨骼重建、代谢疾病等方面应用前景不可忽视,利用基因修饰的间充质干细胞作为载体的基因治疗将为未来医学研究提供更广阔的空间。结论:间充质干细胞具有调节免疫系统的功能,在诱导移植耐受和治疗自身免疫性疾病中存在不可忽略的优势。对于如何有效控制其在体内定向分化、增殖、迁移并整合参与宿主细胞组织功能等问题还需深入系统研究。     

Human blood cells at microgravity: the NASA Initial Blood Storage Experiment

The Initial Blood Storage Experiment (IBSE) probed the behavior of human red cells, white cells, and platelets during exposure to microgravity for 6 days and 2 hours on a National Aeronautics and Space Administration (NASA) shuttle mission, named STS 61-C, which was launched on January 12, 1986. IBSE involved carefully controlled comparisons between two identical sets of blood cells, one exposed to microgravity and the other held on the ground. Specially designed and fabricated, electrically powered environmental chambers provided appropriate environmental temperatures and air flow to support cell metabolism throughout the experiment. To circumvent the need for constant agitation of platelets during storage, a new thin-layer compression method for platelet preservation was developed. Blood cell samples were allocated to the two arms of the experiment, microgravity and earth gravity, by blind assignment. Moreover, to ensure unbiased assessment of the experiment's findings, postexperiment samples for measurement were identified by code. To optimize the chances of detecting possible gravitational effects, a wide array of measurements of cellular function, morphology, metabolism, and immunology were made. Analysis of variance was used in analyzing the data. The most striking finding was that platelets displayed markedly superior structural and functional integrity at microgravity. Granulocytes held on the ground were preserved slightly better than those that orbited in the shuttle, whereas red cells displayed few effects that were attributable to the gravitational variable. Polyvinylchloride-di-(2-ethylhexyl)phthalate (PVC-DEHP) was the plastic of choice for storage of red cells, while PVC-trioctyltrimellitate (TOTM) was superior to PVC-DEHP and polyolefin (PO) for platelets.     

Fractionated proton beam irradiation of pituitary adenomas

PURPOSE： Various radiation techniques and modalities have been used to treat pituitary adenomas. This report details our experience with proton treatment of these tumors. METHODS AND MATERIALS： Forty-seven patients with pituitary adenomas treated with pro- tons, who had at least 6 months of follow-up, were included in this analysis. Forty-two patients underwent a prior surgical resection; 5 were treated with primary radiation.     

青钱柳甜味成分的研究

从青钱柳[Cyclocarya paliurus(Batal.)Iljinsk]嫩叶中分离得到3个(Ⅰ～Ⅲ)有强甜味的化合物。根据理化性质和光谱数据,确定化合物Ⅰ的结构为20,24-环氧-达玛烷-(3β,12β,20S,24R)-12-O-β-D-吡喃鸡纳糖基-3-O-α-L-呋喃阿拉伯糖甙,为一新化合物,命名为青钱柳甙I(cyclocariosideI)。