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71.
BACKGROUND:The high frequency of aneuploidy sperm raises concerns that there may be an increased incidence of aneuploid offspring in ICSI programmes. In order to assess the role that chromosome complement plays in normal and abnormal fertility, detailed molecular cytogenetic studies must be done on sperm samples from men with normal and abnormal fertility. METHODS: To understand more clearly the cytogenetic make-up of sperm from oligoasthenoteratozoospermic (OAT) patients, multi-colour fluorescence in situ hybridization was used to determine numerical chromosome abnormalities. RESULTS: Increased aneuploidy frequencies for chromosomes 13, 18, 21, X and Y were detected in sperm from OAT patients. The frequencies of diploidy also increased. There were no differences in non-disjunction at meiosis I compared to meiosis II. Sperm count inversely correlated with the frequencies of diploidy, aneuploidies for chromosomes 13 and 21 in OAT patients. Twenty-two cycles of ICSI and 18 embryo transfers were performed in 20 couples. Only three cases achieved successful pregnancies. CONCLUSIONS: A higher incidence of meiotic errors and lower sperm counts was found in sperm from OAT patients. 相似文献
72.
Children with temporal lobe epilepsy frequently suffer memory deficits, often marked in face processing. To determine the neural correlates of this dysfunction, we investigated face processing in adolescents with intractable epilepsy compared to typically developing controls. The M170 and M220 MEG event-related fields (ERFs) were recorded while the adolescents completed an n-back task on blocks of upright and inverted faces. Source analyses of the ERF data were performed using an event-related beamforming technique that allowed the detection of multiple sources. The control adolescents showed the expected waveforms and inversion effects, although there were differences in source localization, compared to the adult literature. The participants with epilepsy had poor performance on the tasks. The adolescents with extra-temporal lobe epilepsy showed both the M170 and M220 but the source localizations were highly atypical. The patients with right temporal lobe epilepsy had an absent or highly atypical M220, a component related to face recognition processes. We hypothesize that the children with extra-temporal lobe epilepsy have difficulty with face encoding processes while the patients with right temporal lobe epilepsy have specific difficulty with face recognition. 相似文献
73.
Functional supertype of HLA-A2 in the presentation of Flu matrix p58-66 to induce CD8+ T-cell response in a Northern Chinese population 总被引:3,自引:0,他引:3
The functional supertype of HLA-A2 was investigated in the presentation of the A*0201-restricted Flu matrix p58-66 peptide to activate recall CD8+ T-cell response. In healthy Northern Chinese, the HLA-A2 supertype was mainly composed of the six alleles, A*0201 (26.4%), A*0206 (12.7%), A*0203 (8.2%), A*0207 (7.3%), A*0210 (1.8%) and A*0205 (0.9%), as analyzed by PCR using sequence specific primer (PCR-SSP) and sequence based typing (SBT). The IFN-gamma release Elispot assay was employed to assess effector CD8+ T cells. In A*0201-bearing individuals, the CD8+ T-cell response was potent when stimulated with autologous CD8- PBMCs. The frequency of the effector CD8+ T cells was 96.6% with the magnitude of effector CD8+ T cells of 225 SFC/5 x 104 CD8+ T cells and the RI of 25.7. In non-A*0201 individuals, the effector CD8+ T cells were minimally detectable while the peptide was presented by the autologous CD8- PBMCs. However, the induction of the response of CD8+ T cells obtained from non-A*0201 individuals was remarkably improved when the peptide was presented by autologous dendritic cells instead of CD8- PBMCs. The HLA-A2 alleles possessing cross-reactivity in the peptide presentation were mainly of A*0206 and non-A*0201 heterozygotes of A*0206 and A*0210. Moreover, A*0206 as the HLA-A2 functional supertype was further confirmed by tetramer assay. In two A*0206+ donors with CD8+ T-cell response to the peptide, the CD8+ T-cell frequency assessed by specific binding of peptide HLA-A*0201 tetramer was 4.62% and 1.66%, respectively. Thus, our results have substantiated the immunological relevance of the HLA-A2 supertype, which may benefit the design of peptide vaccines with the potential to be applicable in broader populations. 相似文献
74.
Benedict Wei Jun Pang Shiou-Liang Wee Lay Khoon Lau Khalid Abdul Jabbar Wei Ting Seah Daniella Hui Min Ng Queenie Lin Ling Tan Kenneth Kexun Chen Mallya Ullal Jagadish Tze Pin Ng 《Journal of the American Medical Directors Association》2021,22(4):885.e1-885.e10
ObjectivesTo describe the normative values of sarcopenia among community-dwelling adults (≥21 years of age); compare the prevalence of sarcopenia using Asian Working Group for Sarcopenia criteria, 2014 (AWGS2014), Asian Working Group for Sarcopenia criteria, 2019 (AWGS2019), and European Working Group on Sarcopenia in Older People criteria, 2018 (EWGSOP2) guidelines; and identify factors associated with sarcopenia.DesignParticipants were recruited through random sampling. Sarcopenia assessments were performed using a dual-energy x-ray absorptiometry scan (muscle mass), handgrip test (muscle strength), and usual walking test (physical performance). Questionnaires were administered to evaluate lifestyle and cognition.Setting and ParticipantsIn total, 542 community-dwelling Singaporeans were recruited (21?90 years old, 57.9% women).MethodsWe assessed anthropometry, body composition, and questionnaire-based physical and cognitive factors, and estimated sarcopenia prevalence according to the AWGS2014, AWGS2019, and EWGSOP2 recommendations, and examined associations using logistic regression.ResultsAccording to AWGS2019, the Singapore population-adjusted sarcopenia prevalence was 13.6% (men 13.0%; women 14.2%) overall, and 32.2% (men 33.7%, women 30.9%) in those aged 60 years and above. The cut-offs derived from young adult reference group for low appendicular lean mass index were 5.28 kg/m2 for men and 3.69 kg/m2 for women (lower than AWGS recommended cut-off); for gait speed it was 0.82 m/s, (AWGS2019 recommended cut-off 1.0 m/s, AWGS2014 cut-off was 0.8 m/s); and for handgrip strength it was 27.9 kg/m2 for men and 16.7 kg/m2 for women (close to AWGS2019 recommendation). Age, sex, marital status, alcoholism, physical activity, body mass index, waist circumference, and global cognition were associated with sarcopenia (P < .05).Conclusions and ImplicationsThis is the first study to provide reference values of muscle mass, strength, and gait speed across the adult lifespan of Singaporeans. Using AWGS2019 criteria, sarcopenia is prominent in older age (32.2% in ≥60 years old), but it is already nontrivial (6.9%) among young and middle-age persons. Multidomain lifestyle modifications addressing muscle strength, cognition, and nutrition over the adult lifespan are important to delay the development of sarcopenia. 相似文献
75.
病人知情同意权的几个辩证法问题 总被引:4,自引:2,他引:2
以知情同意为核心的病人自主权是医疗服务和现代医患关系新的支撑点。在人体实验、放弃治疗等领域,充分尊重病人的知情同意权具有极大的现实意义。然而,医生的解释说明、医疗干预和亲属代理同意则构成了对知情同意的限制。因此,必须辩证理解和知情同意的内涵,以最大限度地保障病人利益。 相似文献
76.
Clinical significance and assessment of cytokines in various stages of ulcerative colitis 总被引:2,自引:0,他引:2
Summary In order to study the clinical significance and change of interleukin (IL)-1β and IL-10 concentration in intestinal mucosal
tissues in various stage of ulcerative colitis (UC), IL-1β and IL10 levels were measured by enzyme linked immunosorbent assays
(ELISA). Our results showed that IL-β level caused by spontaneous secretion in the intestinal mucous tissues in active stage
of ulcerative colitis was significantly higher than that in normal controls and in remission stage of ulcerative colitis (P <0. 01,P<0. 001). IL-10 level in various stage of UC was relatively lower in controls, but there was no significantly difference between
the two groups. Our study suggested that higher IL-1β level in active might play an important role in pathogenesis of UC,
and IL-10, as an anti-inflammatory cytokine, was low in active UC, suggesting that it may be a important factor contributing
to the development of higher IL-1β level.
This project was supported by the grant of the Scientific Research Fund of the Ministry of Health (No. 98-2-387). 相似文献
77.
中国北方汉族、维吾尔族、哈萨克族DYS19基因座的遗传多态性 总被引:4,自引:0,他引:4
目的;研究DYS19基因座在中国北方汉族、维吾尔族、哈萨克族群体中的遗传多态性及其法医学应用。方法:应用聚合酶链反应后变性聚丙烯酰胺凝胶电泳分离扩增产物结合银染显带的方法,对101例北方汉族、56例维吾尔族、30例哈萨克族无关男性个体的DYS19基因座进行检测。结果:DYS19基因座在3个群体中共检出5种等位基因,基因频率分布范围分别为0.069-0.594,0.071-0.500,0.100-0.667;个人识别机率分别为0.600,0.675,0.491。χ^2检验表明等位基因分布具有明显的人群差异。家系调查符合单体父系遗传方式。结论:DYS19基因座个人识别机率高,属较高鉴别能力的遗传标记系统,且具有明显的人群分布差异,在法医学及人类遗传学研究中具有重要的应用价值。 相似文献
78.
人胚胎肾上腺皮质褪黑素受体亚型蛋白的分布 总被引:1,自引:0,他引:1
目的:研究褪黑素(Mel)受体亚型在人胚胎肾上腺皮质的分布。方法:应用免疫组化染色检测Mel受体亚型的人胚胎肾上腺皮质的分布。结果:在人胚胎肾上腺皮质的球状速、束状带和网状带均存在Mel受体mt1(Mella)和MT2(Mellb)亚型蛋白的表达,且主要分布于细胞质。结论:人胚胎肾上腺皮质存在Mel受体mt1和MT2亚型。 相似文献
79.
80.
目的 分析养老机构老年人护理服务需求属性,为制订针对性干预措施提供参考.方法 基于Kano模型设计养老机构老年人护理服务需求调查问卷,对天津市7所养老机构共687名老年人进行调查.结果 养老机构老年人护理服务需求34个条目中,魅力属性需求10条(29.4%),均位于保留区Ⅳ;期望属性需求10条(29.4%),其中7条位于优势区Ⅰ;必备属性需求11条(32.4%),其中7条位于待改进区Ⅱ;无差异属性需求3条(8.8%),均位于次要改进区Ⅲ.生理健康与医疗需要维度中,魅力属性2条,期望属性4条,必备属性5条,无差异属性1条;安全需要维度中,期望属性1条,必备属性4条,无差异属性2条;尊重需要维度中,魅力属性1条,期望属性3条,必备属性2条;爱与归属需要维度中,魅力属性4条,期望属性2条;自我实现需要维度的3条均为魅力属性.结论 养老机构老年人必备、期望属性护理服务需求主要集中在生理健康与医疗、安全及尊重需要,魅力属性需求主要集中在爱与归属、自我实现需要.养老机构应在维持和完善必备、期望属性需求的基础上,发展和创新魅力属性需求,客观分析和优化改造无差异属性需求. 相似文献