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1.
Inference of biogeographic origin is an important factor in clinical, population and forensic genetics. The information provided by AIMs (Ancestry Informative Markers) can allow the differentiation of major continental population groups, and several AIM panels have been developed for this purpose. However, from these major population groups, Eurasia covers a wide area between two continents that is difficult to differentiate genetically. These populations display a gradual genetic cline from West Europe to South Asia in terms of allele frequency distribution. Although differences have been reported between Europe and South Asia, Middle East populations continue to be a target of further investigations due to the lack of genetic variability, therefore hampering their genetic differentiation from neighboring populations. In the present study, a custom-built ancestry panel was developed to analyze North African and Middle Eastern populations, designated the ‘NAME’ panel. The NAME panel contains 111 SNPs that have patterns of allele frequency differentiation that can distinguish individuals originating in North Africa and the Middle East when combined with a previous set of 126 Global AIM-SNPs.  相似文献   
2.
目的探讨Reiter综合征的病因、临床特点、治疗方法. 方法报告2例并检索收集国内文献171例,共计173例Reiter综合征,对其临床资料进行分析讨论. 结果 173例Reiter综合征的男女之比为5.41,平均发病年龄为27±10岁.完全型126例,不完全型67例.继发干感染106例,HLA-B27阳性59/72例.控制感染后经消炎痛、泼昆松、甲氨蝶呤等治疗后,均能达到临床完全缓解. 结论 Reiter综合征是病原体感染诱发的自身免疫性疾病,预后良好.  相似文献   
3.
对我国目前麻风防治策略的思考   总被引:1,自引:0,他引:1  
1949-2008年我国累计登记麻风患者48万余例,主要分布在北纬38°以南的东南沿海和长江流域省份.新中国成立后,经过积极防治,至20世纪80年代初,以氨苯砜单疗治愈的患者达31万余例;1986年在全国普遍推广WHO联合化疗方案,至2008年底全国累计接受联合化疗的麻风患者近8万例.  相似文献   
4.
Spatial analysis of (90)Sr artificial radionuclide in consequence of global fallout and Chernobyl nuclear accident has been carried out by using the point cumulative semivariogram (PCSV) technique based on 40 surface water station measurements in Keban Dam Lake during March, April, and May 2006. This technique is a convenient tool in obtaining the regional variability features around each sampling point, which yields the structural effects also in the vicinity of the same point. It presents the regional effect of all the other sites within the study area on the site concerned. In order to see to change of (90)Sr, the five models are constituted. Additionally, it provides a measure of cumulative similarity of the regional variable, (90)Sr, around any measurement site and hence it is possible to draw regional similarity maps at any desired distance around each station. In this paper, such similarity maps are also drawn for a set of distances. (90)Sr activities in lake that distance approximately 4.5 km from stations show the maximum similarity.  相似文献   
5.
BACKGROUND: Preservation of hair follicle units for the purpose of delayed transplant will help us graft thousands of hair grafts at one session, even in a clinic with fewer assistants and less equipment. OBJECTIVE: This study was undertaken to evaluate and compare the viability of hair follicle units preserved at 0 and 4 degrees C for various periods. MATERIALS AND METHODS: Cell cultures and transplant of hair follicle units into athymic mice were performed. RESULTS: Outer root sheath cells could be cultivated in 96% (0 degrees C group) and 92% (4 degrees C group) of the hair follicles after 24 hours of preservation, whereas 85% (0 degrees C group) and 79% (4 degrees C group) of the follicles implanted into the mice regrew well after the same period of preservation. Then, in both the 0 degrees C and the 4 degrees C group, these rates decreased significantly with length of preservation in cell cultures and mice transplant; however, 0 degrees C seems better than 4 degrees C for preservation of grafts (p<.05). CONCLUSION: Grafts are better preserved at 0 degrees C instead of 4 degrees C. When delayed transplant is an option, it should be completed within 24 hours and no later than 48 hours.  相似文献   
6.
HLA-DRB1、DQB1基因与汉族人群寻常型天疱疮的相关性研究   总被引:4,自引:0,他引:4  
目的 探讨 HL A- DRB1、DQB1位点基因在汉族人群寻常型天疱疮易感性中的作用。方法用序列特异性引物 -聚合酶链反应方法 ,对 6 1例寻常型天疱疮 (pemphigus vulgaris,PV)患者和 5 7名正常对照进行了 HL A- DRB1、DQB1等位基因的分型 ,并分析了 DRB1、DQB1基因在两组中的分布。结果 与正常对照组比较 ,PV组 DR4、DRB1* 14 (* 14 0 1、* 14 0 4、* 14 0 5 )基因频率明显增高 (Pc分别 <0 .0 5及P<0 .0 1) ,差异有显著性 ;PV组 DQB1* 0 5 0 3、DQB1* 0 30 2基因频率明显增高 (Pc均 <0 .0 5 ) ,差异有显著性。对 DR4阳性样本的组内基因亚型分型结果发现 ,PV组中 DRB1* 0 4 0 3、DRB1* 0 4 0 6频率显著增高(Pc<0 .0 5 ) ,差异有显著性。 PV患者组单倍型 HL A- DRB1* 0 4 ,DQB1* 0 30 2和 HL A- DRB1* 14 ,DQB1* 0 5 0 3频率明显增高 (P<0 .0 5 )。结论 HL A- DRB1* 0 4 ,DQB1* 0 30 2和 HL A- DRB1* 14 ,DQB1* 0 5 0 3可能是汉族人 PV推测的易感单倍型。  相似文献   
7.
Epidemiological study of pathogenic fungi in China: 1986 and 1996   总被引:2,自引:2,他引:0  
目的 研究 1986年 - 1996年 ,我国致病真菌菌群的变化情况。方法  1986年 1月 1日 - 12月 31日和 1996年 1月 1日 - 12月 31日在全国 2 5个省、市、自治区 4 0多个有代表性的单位对临床或现场确定的致病菌进行了动态研究 ,就病原菌变迁、各区动态情况和具体疾病等作了详细分析。结果 发现 10年间较易治疗的皮肤癣菌比例下降 ,而较难治疗的酵母菌和霉菌比例升高。结论  10年间致病真菌菌群的变化较大 ,我们应根据变化情况进行相应的研究及制定出相应治疗措施  相似文献   
8.
9.
用DNA microarray快速检测淋球菌耐喹诺酮类药物基因突变   总被引:1,自引:0,他引:1  
研究DNA microarray的制备及其检测淋球菌耐喹诺酮类药物基因突变的准确性。方法根据淋球菌药敏及测序结果分别对淋球菌gyrA和parC基因的序列设计特异引物和探针并制作DNA microarray。对淋球菌临床拭子进行PcR扩增并荧光标记包含gyrA和parC基因的目的DNA片段,与芯片杂交,同时以测序法进行双盲淋球菌耐喹诺酮类药物基因突变的检测。结果87份泌尿生殖道试子全部可用DNA microarray检测出来,芯片检测结果与药敏结果符合率为100%,与测序结果符合率为97.7%。结论用DNA microarray来检测淋球菌gyrA和parC基因突变快速、特异性高和灵敏度高,可以应用于临床耐药性检测。  相似文献   
10.
For the proper regulation of a carcinogenic material it is necessary to fully understand its mode of action, and in particular whether it demonstrates a threshold of effect. This paper explores our present understanding of carcinogenicity and the mechanisms underlying the carcinogenic response. The concepts of genotoxic and non-genotoxic and threshold and non-threshold carcinogens are fully described. We provide summary tables of the types of cancer considered to be associated with exposure to a number of carcinogens and the available evidence relating to whether carcinogenicity occurs through a threshold or non-threshold mechanism. In light of these observations we consider how different regulatory bodies approach the question of chemical carcinogenesis, looking in particular at the definitions and methodologies used to derive Occupational Exposure Levels (OELs) for carcinogens. We conclude that unless proper differentiation is made between threshold and non-threshold carcinogens, inappropriate risk management measures may be put in place - and lead also to difficulties in translating carcinogenicity research findings into appropriate health policies. We recommend that clear differentiation between threshold and non-threshold carcinogens should be made by all expert groups and regulatory bodies dealing with carcinogen classification and risk assessment.  相似文献   
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