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21.
Objective

The International Federation of Gynecology and Obstetrics (FIGO) 2000 scoring system classifies gestational trophoblastic neoplasia (GTN) patients into low- and high-risk groups, so that single- or multi-agent chemotherapy can be administered accordingly. However, a number of FIGO-defined low-risk patients still exhibit resistance to single-agent regimens, and the risk factors currently adopted in the FIGO scoring system possess inequable values for predicting single-agent chemoresistance. The purpose of this study is therefore to evaluate the efficacy of risk factors in predicting single-agent chemoresistance and explore the feasibility of simplifying the FIGO 2000 scoring system for GTN.

Methods

The clinical data of 578 GTN patients who received chemotherapy between January 2000 and December 2018 were retrospectively reviewed. Univariate and multivariate logistic regression analyses were carried out to identify risk factors associated with single-agent chemoresistance in low-risk GTN patients. Then, simplified models were built and compared with the original FIGO 2000 scoring system.

Results

Among the eight FIGO risk factors, the univariate and multivariate analyses identified that pretreatment serum human chorionic gonadotropin (hCG) level and interval from antecedent pregnancy were consistently independent predictors for both first-line and subsequent single-agent chemoresistance. The simplified model with two independent factors showed a better performance in predicting single-agent chemoresistance than the model with the other four non-independent factors. However, the addition of other co-factors did improve the efficiency. Overall, simplified models can achieve favorable performance, but the original FIGO 2000 prognostic system still features the highest discrimination.

Conclusions

Pretreatment serum hCG level and interval from antecedent pregnancy were independent predictors for both first-line and subsequent single-agent chemoresistance, and they had greater weight than other non-independent factors in predicting single-agent chemoresistance. The simplified model composed of certain selected factors is a promising alternative to the original FIGO 2000 prognostic system, and it shows comparable performance.

  相似文献   
22.

Objective

To investigate stretch-induced electrophysiological changes in chronically infarcted hearts and the effect of streptomycin (SM) on these changes in vivo.

Methods

Sixty Wistar rats were divided randomly into four groups: a control group (n=15), an SM group (n=15), a myocardial infarction (MI) group (n=15), and an MI+SM group (n=15). Chronic MI was obtained by ligating the left anterior descending branch (LAD) of rat hearts for eight weeks. The in vivo blockade of stretch-activated ion channels (SACs) was achieved by intramuscular injection of SM (180 mg/(kg·d)) for seven days after operation. The hearts were stretched for 5 s by occlusion of the aortic arch. Suction electrodes were placed on the anterior wall of left ventricle to record the monophasic action potential (MAP). The effect of stretching was examined by assessing the 90% monophasic action potential duration (MAPD90), premature ventricular beats (PVBs), and ventricular tachycardia (VT).

Results

The MAPD90 decreased during stretching in both the control (from (50.27±5.61) ms to (46.27±4.51) ms, P<0.05) and MI groups (from (65.47±6.38) ms to (57.47±5.76 ms), P<0.01). SM inhibited the decrease in MAPD90 during inflation ((46.27±4.51) ms vs. (49.53±3.52) ms, P<0.05 in normal hearts; (57.47±5.76) ms vs. (61.87±5.33) ms, P<0.05 in MI hearts). The occurrence of PVBs and VT in the MI group increased compared with that in the control group (PVB: 7.93±1.66 vs. 1.80±0.86, P<0.01; VT: 7 vs. 1, P<0.05). SM decreased the occurrence of PVBs in both normal and MI hearts (0.93±0.59 vs. 1.80±0.86 in normal hearts, P<0.05; 5.40±1.18 vs. 7.93±1.66 in MI hearts, P<0.01).

Conclusions

Stretch-induced MAPD90 changes and arrhythmias were observed in chronically infarcted myocardium. The use of SM in vivo decreased the incidence of PVBs but not of VT. This suggests that SACs may be involved in mechanoelectric feedback (MEF), but that there might be other mechanisms involved in causing VT in chronic MI.  相似文献   
23.
分析了浙江省区域产业集群中企业信息需求的变化及特征,探讨了当前科技信息服务的现状和存在问题.在借鉴新的服务手段、服务方式、服务经验的基础上,结合浙江省区域产业集群的科技信息服务实践,探求科技信息服务新策略,提出基于区域产业特色的科技信息服务发展的思路.  相似文献   
24.
提出一种基于树状小波的图像融合,其基本思想是首先对源图像进行树状小波分解,之后采用基于像素、区域的选择或边缘检测的融合算法来构造融合图像的小波系数,最后通过树状小波逆变换重构得到融合图像.此外,利用熵、图像均值、均方根误差、峰值信噪比等参量对该融合方法的融合性能进行评价与分析.实验结果表明该融合方法是有效的.  相似文献   
25.
In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of assessing the quality of routine care in general practice. For a measure to have clinical usefulness it must not only be valid, appropriate, reliable, responsive, and capable of being interpreted, but it must also be simple, fast to complete, easy to score, and provide useful clinical data. The Two-step method of choosing appropriate measures is introduced. Then through comparison of generic instruments with disease-specific instruments, we can conclude that sometimes a combination of generic and disease-specific HRQOL measures may be more appropriate for monitoring changes in a patient's health status due to an intervention.  相似文献   
26.
浙江省已于2014年启动科技报告制度建设工作,并将在“十三五”期间建成全省统一的科技报告管理体 系,对浙江省科技报告制度建设进行研究探讨有着重要意义。文章简述浙江省科技报告制度建设的基本思路,介绍开 展制度建设一年来浙江省工作特色与成效,并建议从以下4方面入手深入推进浙江省科技报告工作:进一步实现与科研 项目管理的无缝衔接,推行科技报告规范化管理,建立和完善科技报告质量评价机制,进一步完善科技报告开放和共 享机制。  相似文献   
27.
徐蕾  李庆  肖相泽 《现代情报》2018,38(6):157-164
[目的/意义]本文在已有的关于大数据政策研究基础上,分析当前国内的大数据政策的关注焦点与不足,为后续的政策创新提供参考借鉴。[方法/过程]以9个国家级大数据综合试验区2014年11月至2017年11月出台的政策为研究样本,综合运用扎根理论、词频分析和政策力度测量方法,确立政策关键词的权重,借鉴Ochiia系数得出关键词共词矩阵,利用可视化分析工具获取共词网络。并综合运用度中心性研究、聚类分析、多维尺度分析和社会网络分析方法研究网络的结点特征与网络结构。[结果/结论]发现现阶段我国大数据试验区政策重点关注金融财税对大数据发展的支持、大数据产业的集聚发展、基本的制度建设和基础设施建设、创新发展应用等方面。对于产业引导基金、核心企业培育、大数据的深层次应用以及外部技术的引进等方面存在不足。  相似文献   
28.
BackgroundAvailability of related rice species is critical for rice breeding and improvement. Two distinct species of domesticated rice exist in the genus Oryza: Oryza sativa (Asian rice) and Oryza glaberrima (African rice). New rice for Africa (NERICA) is derived from interspecific crosses between these two species. Molecular profiling of these germplasms is important for both genetics and breeding studies. We used 30 polymorphic SSR markers to assess the genetic diversity and molecular fingerprints of 53 rice genotypes of O. sativa, O. glaberrima, and NERICA.ResultsIn total, 180 alleles were detected. Average polymorphism information content and Shannon's information index were 0.638 and 1.390, respectively. Population structure and neighbor-joining phylogenetic tree revealed that 53 genotypes grouped into three distinct subpopulations conforming to the original three groups, except three varieties (IR66417, WAB450-4, MZCD74), and that NERICA showed a smaller genetic distance from O. sativa genotypes (0.774) than from O. glaberrima genotypes (0.889). A molecular fingerprint map of the 53 accessions was constructed with a novel encoding method based on the SSR polymorphic alleles. Ten specific SSR markers displayed different allelic profiles between the O. glaberrima and O. sativa genotypes.ConclusionsGenetic diversity studies revealed that 50 rice types were clustered into different subpopulations whereas three genotypes were admixtures. Molecular fingerprinting and 10 specific markers were obtained to identify the 53 rice genotypes. These results can facilitate the potential utilization of sibling species in rice breeding and molecular classification of O. sativa and O. glaberrima germplasms.  相似文献   
29.
关于促进专业图书馆工作发展的两个建议案   总被引:1,自引:0,他引:1  
为了促进专业图书馆工作的发展,文章分别就目前专业图书馆存在的科普宣传意识淡薄和现代化服务手段建设滞后现象进行了分析,提出了"关于专业图书馆开展社会化科普活动的建议案"与"关于倡导专业图书馆建立眼务主导型数字信息平台的建议案".也对具体运作做了简述.落实这些提案,将有助于专业图书馆利用所藏丰富资源,有助于维护人民群众的基本文化权益,有助于公共图书馆服务质量的提高.  相似文献   
30.
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