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91.
目的 探讨河南汉族群体的D1S5 49、D3S175 4、D2 2S683和CSF1PO、TPOX、TH0 1基因座遗传多态性分布。方法 ACD抗凝血样采自 2 19名无血缘关系汉族个体 ,酚 氯仿法提取DNA ,应用复合扩增技术对D1S5 49等 6个短串重复序列 (STR)基因座进行扩增 ,采用高分辨率的聚丙烯酰胺凝胶电泳分离、银染法显影技术。统计各基因频率、计算杂合度、多态信息含量、个人识别概率及亲权否定概率。结果  6个STR基因座基因频率的分布均符合Hardy Weinberg平衡 ,各基因座的杂合度分别为 0 .7964、0 .72 3 1、0 .815 9、0 .75 81、0 .65 2 3、0 .6816;非父排除概率为 0 .62 46、0 .4914、0 .65 0 1、0 .5 2 3 6、0 .40 98、0 .42 87;个人识别机率为 0 .8996、0 .8781、0 .92 3 1、0 .8896、0 .8167、0 .83 92 ;多态信息含量为 0 .72 16、0 .6994、0 .742 1、0 .7169、0 .65 17、0 .710 6。结论 D1S5 49等 6个STR基因座是一组高度多态性的遗传标记系统 ,在人类遗传学及法医学研究中具有重要意义  相似文献   
92.
The effect associated with the substitution of adenine (A) for guanidine (G) in the promoter region of the apolipoprotein AI gene (?75 bp) with plasma apo AI and high-density lipoprotein (HDL) levels was investigated in the European Atherosclerosis Research Study (EARS). This is a study of healthy offspring (cases) of fathers who had suffered premature myocardial infarction (MI) before age 55 years (n = 565) and age- and sex-matched controls (n = 1,078) from 12 European countries, divided into 5 regions based on geography and language. The frequency of the polymorphism was not significantly different among the regions and the relative frequency of the rare A allele was similar in cases and controls (0.159 vs. 0.142) combining data from all regions. Individuals with one or more A allele had significantly higher plasma apo AI levels (P < 0.05) than individuals homozygous for the G allele. This effect was consistent in all regions. The data were analyzed separately in males and females. In females, those with one or more A allele had significantly higher apo AI levels (P = 0.05) than individuals homozygous for the G allele, and this raising effect of the A allele was greater in cases than controls for both apo AI (5.23% vs. 1.56%) and HDL (4.48% vs. 1.89%). In males, the A allele was associated with higher levels of apo AI and HDL, but the effect was much smaller and the differences did not reach statistical significance. In the females, where the effect of the A allele was strongest, the effect on apo AI associated with genotype was evident in non-smokers, and individuals with one or two A alleles had 3.6% higher apo AI and 3.14% higher HDL levels than individuals homozygous for the G allele. However, in the female smokers the raising effect of the A allele was greatly reduced (0.56%). Thus genetic variation in the promoter region of the apo AI gene is associated with differences in apo AI and HDL levels in healthy individuals throughout Europe, but the effect is modulated by gender, environmental factors such as smoking, and a family history of MI.  相似文献   
93.
为研究广东省乙型肝炎 (乙肝 )疫苗纳入计划免疫管理 10年后儿童血清乙肝病毒感染标志物 (HBVM )的变化 ,采用分层多阶段随机抽样法 ,将全省分 4层 ,共抽取 12个县 2 4个村的 196 3名儿童为研究样本。采血用固相放射免疫法 (SPRIA)检测乙肝病毒表面抗原 (HBsAg)、乙肝病毒核心抗体 (抗 HBc)、乙肝病毒表面抗体 (抗 HBs)。2 0 0 2年调查 1~ 14岁儿童乙肝疫苗接种率为 78 81% ,全程接种率为 74 17%。其中 1~ 9岁儿童乙肝疫苗全程接种率为 81 73% ,10~ 14岁为 6 0 32 %。 1~ 14岁儿童HBsAg携带率、抗 HBc阳性率、HBV感染率分别从 1992年的 19 86 %、5 3 5 9%、71 4 1%降至 2 0 0 2年的 8 5 6 %、2 2 5 7%、31 33%。其中 1~ 9岁儿童的HBsAg携带率、抗 HBc阳性率、HBV感染率分别从 1992年的 17 88%、4 7 0 9%、6 7 4 4 %下降至 2 0 0 2年的 5 75 %、14 4 9%、2 1 81%。乙肝疫苗接种后 ,1~ 3岁儿童抗 HBs阳性率为 5 2 0 2 %~ 6 2 18%。由于实施了加强免疫 ,4~ 14岁儿童的抗 HBs维持在 5 9 32 %~ 6 5 80 %。广东省乙肝疫苗纳入计划免疫管理 10年后 ,全省 1~ 14岁儿童HBV感染率已大幅度下降 ,抗 HBs阳性率大幅度升高 ,取得了良好的经济和社会效益。  相似文献   
94.
Guard honeybees stand at the entrance of colonies and facilitate the exclusion of nonnestmates from the colony. In this study, we examined the hypothesis that genetic variability among individuals in colonies might explain variability in guarding activity. To do this, we cross-fostered honey bees between colonies with high-defensive responses and colonies with low-defensive responses in alarm pheromone tests. Individuals from high-defensive colonies were more likely to guard in their own colonies (controls) than cross-fostered bees from low-defensive colonies. Cross-fostered high-defensive bees also were more likely to guard in low-defense colonies. These results support the hypothesis that interindividual differences in guarding behavior are at least partially under genetic control. A positive correlation between number of guards and response to alarm pheromone demonstrates a link between behaviorally separated components of the overall defensive response.This work was supported by NSF Grant BNS 8605604.  相似文献   
95.
Systolic and diastolic blood pressures were measured on 254 monozygotic (MZ) and 260 dizygotic (DZ) male twin pairs, during middle age (average age 48 years) and at two later age points. Genetic and environmental components of covariation were modeled by time series. For both measures, shared environmental influences were absent and specific environmental influences were largely time-specific. Although heritability was about 0.5 at each time point, genetic variation present at middle age contributed only about 60% to that present 9 years later, the remaining 40% being new. Fifteen years later, at the third time point, no new genetic variation was evident, variation in individual differences being entirely attributable to genetic differences laid down at the two earlier ages. © 1993 Wiley-Liss, Inc.  相似文献   
96.
Molecular genetic analysis was performed in a patient with cytochrome b positive X-linked chronic granulomatous disease. A previous Southern blot study, using a cytochrome b heavy chain cDNA as probe, revealed a Pst I restriction fragment pattern for the cytochrome b heavy chain gene (CYBB) different to that of normal individuals. Since restriction length polymorphism with Pst I has never been observed in control individuals and no abnormal restriction fragment patterns in the patient's CYBB was detected with seven other enzymes used, we focussed on the single Pst I site in the CYBB cDNA as being the only mutation site responsible for his disease. A fragment of the patient's cDNA which included the Pst I site was amplified by reverse polymerase chain reaction, and loss of the Pst I site in the fragment was confirmed by incubation with Pst I. Subsequent sequence analysis of the fragment revealed a point mutation in the Pst I site (cytosine to adenine), substituting glutamic acid for alanine at position 57.  相似文献   
97.
The genes of the major histocompatibility complex (MHC) are amongst the most polymorphic loci known in the human population. The population genetics of the MHC encoded HLA loci of sub-Saharan Africa are of major interest because of their particular genetic diversity. Here we report on the HLA-DR 52- and 51-associated determinants of the DRB1 loci observed in 165 East African individuals studied in Nairobi, Kenya. The HLA-DR typing was done by serologic and by molecular DNA techniques (PCR-SSOP). The most frequent allele identified was DRB1*1101, followed by DRB1*1503 and DRB1*1302. Some unexpected alleles were repeatedly identified: DRB1*1108, DRB1*1316 and DRB1*1421. Most oftheDR 52-and 51-associated DRB1 alleles were correctly identified by serology as part of the DR3, DR5, DR6 and DR2 groups respectively. The HLA-DRB1 profile reported here corroborates previous genetic and linguistic data supporting the concept that the Eastern African Black population is genetically distinct from other African Black populations. This has important implications in public health issues related to the genetic profile of a population (transplantation, vaccine design for example).  相似文献   
98.
Electroencephalogram (EEG) recordings were made from 26 pairs of monozygotic (MZ) and 26 pairs of dizygotic (DZ) adult male twins, before and after alcohol ingestion. After a baseline EEG and a light breakfast, 1.2 ml/kg of ethanol was given orally over 15 min and the EEG repeated four times at hourly intervals. Alcohol caused a significant drop in the percentage of beta waves (14-30 cycles/sec) during the 1st hr. For the percentage of beta waves in 38 pairs of twins with complete data, MZ twin beta-wave intraclass correlations (RMZ) ranged between 0.85 and 0.91 before and after alcohol, but the DZ intraclass correlations (RDZ) started at 0.54 and fell to 0.05 at 2 hr after alcohol before recovering to baseline levels. These correlations resulted in heritability estimates [2(RMZ-RDZ)] of 0.68 at baseline and 1.73 at 2 hr. A heritability of 1.43 was found for the 1st hr drop in percentage of beta waves (RMZ = 0.78, RDZ = 0.06). These unrealistically high heritabilities, due to RDZ's approaching 0.0, suggest a failure of assumptions in the linear twin model that was used. Also, these findings are similar to, but more exaggerated than, findings in resting EEG's and visually evoked EEG potentials of twins and are compatible with the influence of gene interactions.  相似文献   
99.
A vaccination trial, performed on 86 3-month-old infants, has shown that the ability of the RIT 4237 live attenuated rotavirus strain to induce seroconversion is dramatically reduced when administered with live poliovirus vaccine. In a subsequent trial performed on 93 infants the attempt to overcome the poliovirus interference by administering two doses of associated vaccines was unsuccessful. No interference by the RIT 4237 strain on live attenuated polioviruses was observed.  相似文献   
100.
Abstract: Most individuals concerned about hereditary breast cancer risk will neither order nor benefit from genetic testing at the present time. Many will, however, seek information about their risk and testing. Risk assessment services, in addition to providing information about hereditary risk and genetic testing, need also to include assessment of non-hereditary risks, information about how to evaluate risks, early detection modalities, the etiology of cancer, and assistance in devising follow-up health care plans. Psychosocial factors, particularly those pertaining to the individual's past history with illness and beliefs about causes and prognosis, must be taken into account to provide relevant information that is understood. A case history with examples of some of the types of information that lead to informed consent in a cancer risk assessment setting is provided.  相似文献   
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