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101.
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
102.
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
103.
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
104.
胃癌 (Gastric Cancer,GC) 是全球第五大最常见的恶性肿瘤,也是第四大癌症死亡相关原因。胃癌异质性明显,肿瘤微环境复杂,免疫检查点抑制剂虽然在晚期胃癌中展现出一定抗肿瘤疗效,但获益人群仍在少数。吲哚胺2,3-双加氧酶 1 (Indoleamine 2,3-Dioxygenase 1,IDO1) 是色氨酸沿犬尿氨酸途径代谢中的关键酶,对肿瘤免疫逃逸起到了关键作用。目前已有多项研究表明IDO1在胃癌发生发展及幽门螺杆菌感染和EB病毒感染中发挥重要作用,所以靶向IDO1有望成为胃癌免疫治疗的新策略。本文就IDO1作用机制、IDO1在胃癌及相关疾病中的研究进展及IDO1抑制剂在胃癌中的应用前景进行综述。 相似文献
105.
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
106.
该院将PDCA循环、根因分析这两个管理工具引入医院静脉血栓栓塞症(VTE)的精细化管理中,形成了以质控科为圆心,围绕圆心的一环为VTE防治管理委员会及VTE快速反应团队、二环为临床科室VTE防治管理小组的同心圆模式的管理体系.以回顾性分析1例医院相关性VTE事件的发生为例,剖析环节中尚存在的缺陷,进行多方位自我检查,健全了医院VTE管理体系,显著提升了全院VTE评估合格率、预防措施实施率,降低了医院相关性VTE发生率、致死性PTE发生率. 相似文献
107.
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
108.
我院自1995~1999年行单发多子囊肝包虫囊肿切除38例,取得较好效果,报道如下。 1 临床资料 1.1 一般资料 本组38例,男22例,女16例,年龄18~40岁,平均29岁。肝包虫囊肿位于肝右叶32例(右肝Ⅱ段5例、Ⅵ段10例、Ⅶ段10例),位于肝右叶6例(Ⅱ段3例、Ⅳ段3例)。切除最大囊肝4cm×2cm,最小2cm×1.5cm。1.2手术方式本组均行手术切除。在常温肝门间歇性血流阻断下,行肝局部切除14例,各类肝 相似文献
109.
比较国产与进口吲哚美辛缓释胶囊在人体内的生物利用度和生物等效性.18名健康男性志愿者双周期随机交叉口服吲哚美辛缓释胶囊75 mg,用反相高效液相色谱法测定达稳态后的血药浓度.受试制剂与参比制剂的达峰时间(Tpeak)分别为(3.78±1. 00)h和(3.50±1.29)h;达峰浓度(Cmax)分别为(7.51±2.74)ug/ml和(8.05±2.58)ug/ml;药时曲线面积(AUC)分别为(66.41±30.12)和(63.90±26.50)ug@ml-1@h-1.多次给药达稳态条件下,国产的吲哚美辛缓释胶囊与进口制剂的相对生物利用度为(103.20±21.90)%.双单侧检验表明,国产与进口吲哚美辛缓释胶囊具有生物等效性. 相似文献
110.
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