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41.
采用免疫组化SP法检测Livin和Fhit在30例正常子宫内膜和70例子宫内膜癌组织中的表达,研究凋亡抑制蛋白Livin和Fhit在子宫内膜癌中的表达和意义。结果显示Livin蛋白在正常子宫内膜组织中表达明显低于子宫内膜癌组织(P<0.05);Fhit蛋白在正常子宫内膜组织中表达明显高于子宫内膜癌组织(P<0.05);在子宫内膜癌组织中,随组织学分级和病理分期的增加,Livin蛋白表达阳性率逐渐上升,Fhit蛋白表达阳性率逐渐下降,而且Fhit蛋白表达与淋巴结转移相关(P<0.05);Livin蛋白和Fhit蛋白表达呈负相关(P<0.05)。结果提示Livin和Fhit异常表达可能与子宫内膜癌的发生、发展关系密切,联合检测Livin和Fhit有助于子宫内膜癌早期诊断、治疗及预后判断。 相似文献
42.
目的:探讨TCT(液基薄层细胞学)与阴道镜下活检的吻合程度,分析不同医生的诊断吻合度,最大限度提高TCT作为宫颈癌筛查手段的的准确性。方法:选取2007年2月至2010年9月期间来我院进行妇科体检TCT异常病例3 226人次的TCT诊断报告与阴道镜活检诊断结果进行比较,以病理活检作为最后诊断。结果:三位主治医生中甲的阅片吻合率为73.98%,乙的吻合率为77.04%,丙的吻合率为82.30%,总的吻合率为78.18%,三者间比较差异极显著(χ2=22.42,P〈0.000 1)。结论:1)TCT细胞学检查与传统的细胞学方法相比取材方便,无创,确诊率高,是宫颈癌筛查的重要方法。2)医生经验在诊断过程中起重要作用,加强对医务人员的培养,适时培训是提高TCT确诊率的重要环节。 相似文献
43.
胡萍 《昭通师范高等专科学校学报》2011,33(5):73-76
随着科学技术的发展,多媒体教学在英语口语教学中越来越重要,教师可以利用多媒体和网络教学提供更为广阔而真实的空间进行情景教学,选择恰当的多媒体教学模式,激发学生讲英语的兴趣,促使学生积极思维、主动参与语言实践,使教学效率达到最优化,从而达到英语口语教学事半功倍的作用. 相似文献
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基于带内自回传小基站系统,提出一种以用户为中心动态成簇的部分协作干扰抑制方案。根据带内自回传小基站复用接入与回传无线资源的特点,形成以最大化系统下行接入链路吞吐量为目标,联合回传链路资源分配与接入链路预编码设计的优化问题。由于所提问题难以获得最优解,基于凸松弛和分块坐标下降方法,提出一种次优的迭代求解算法。仿真结果表明所提算法能根据回传速率调整协作簇的大小,均衡小基站回传负载,提升系统接入链路的吞吐量。 相似文献
48.
Shenqiang Wang Letao Yang Bolei Cai Fuwei Liu Yannan Hou Hua Zheng Fang Cheng Hepeng Zhang Le Wang Xiaoyi Wang Qianxin Lv Liang Kong Ki-Bum Lee Qiuyu Zhang 《国家科学评论(英文版)》2022,9(4)
Cartilage injuries are often devastating and most cannot be cured because of the intrinsically low regenerative capacity of cartilage tissues. Although stem-cell therapy has shown enormous potential for cartilage repair, the therapeutic outcome has been restricted by low survival rates and poor chondrocyte differentiation in vivo. Here, we report an injectable hybrid inorganic (IHI) nanoscaffold that facilitates fast assembly, enhances survival and regulates chondrogenic differentiation of stem cells. IHI nanoscaffolds that strongly bind to extracellular matrix (ECM) proteins assemble stem cells through synergistic 3D cell–cell and cell–matrix interactions, creating a favorable physical microenvironment for stem-cell survival and differentiation in vitro and in vivo. Additionally, chondrogenic factors can be loaded into nanoscaffolds with a high capacity, which allows deep, homogenous drug delivery into assembled 3D stem-cell-derived tissues for effective control over the soluble microenvironment of stem cells. The developed IHI nanoscaffolds that assemble with stem cells are injectable. They also scavenge reactive oxygen species and timely biodegrade for proper integration into injured cartilage tissues. Implantation of stem-cell-assembled IHI nanoscaffolds into injured cartilage results in accelerated tissue regeneration and functional recovery. By establishing our IHI nanoscaffold-templated 3D stem-cell assembly method, we provide a promising approach to better overcoming the inhibitory microenvironment associated with cartilage injuries and to advance current stem-cell-based tissue engineering. 相似文献
49.
Junzhen Ren Pengqing Bi Jianqi Zhang Jiao Liu Jingwen Wang Ye Xu Zhixiang Wei Shaoqing Zhang Jianhui Hou 《国家科学评论(英文版)》2021,8(8)
Developing photovoltaic materials with simple chemical structures and easy synthesis still remains a major challenge in the industrialization process of organic solar cells (OSCs). Herein, an ester substituted poly(thiophene vinylene) derivative, PTVT-T, was designed and synthesized in very few steps by adopting commercially available raw materials. The ester groups on the thiophene units enable PTVT-T to have a planar and stable conformation. Moreover, PTVT-T presents a wide absorption band and strong aggregation effect in solution, which are the key characteristics needed to realize high performance in non-fullerene-acceptor (NFA)-based OSCs. We then prepared OSCs by blending PTVT-T with three representative fullerene- and NF-based acceptors, PC71BM, IT-4F and BTP-eC9. It was found that PTVT-T can work well with all the acceptors, showing great potential to match new emerging NFAs. Particularly, a remarkable power conversion efficiency of 16.20% is achieved in a PTVT-T:BTP-eC9-based device, which is the highest value among the counterparts based on PTV derivatives. This work demonstrates that PTVT-T shows great potential for the future commercialization of OSCs. 相似文献
50.
Trevor N. Simper Cecile Morris Anthony Lynn Ciara O'Hagan Karen Kilner 《运动与健康科学(英文)》2020,9(6):645-650
BackgroundOne-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.MethodsThirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m2; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.ResultsThere were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).ConclusionThe results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity. 相似文献