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活血皇浆对田径运动员血液动力流变学和血液有形成分参数的影响 总被引:2,自引:1,他引:1
根据中医内科辩证和因时制宜原则 ,对校田径代表队在夏季比赛期间服用活血皇浆前后进行血液动力流变学和血液有形成分参数的比较观察结果表明 ,运动员服液后在脉率 (PR)、每搏量 (SV)、心输出量 (CO)、左心有效泵力 (VPE)和左心能量有效利用率 (EWK )改善的同时 ,出现心肌耗氧量 (HOV)、心肌耗氧指数 (HOI)、心肌血液需要量 (CMBN)、心肌血液灌注量(CMBV)和总周阻 (TPR)、标准周阻 (SPR)、收缩压 (SP)舒张压 (DP)等参数下降 ,呈现机能和能量节省化 ,而血液状态则表现为血容量 (BV)增多 ,全血粘度 (η)和还原血粘度 (ηr)下降 ,切变应力增高 ,血流速度加快 ,有利于维持微循环正常功能。血液有形成分的改变提示 ,血红蛋白 (Hb)红细胞比积 (HCT)和血小板 (PL T)有增高趋势 ;平均红细胞血红蛋白浓度 (MCHC)下降 ,则有可能与 BV相对增多 ,红细胞 (RBC)体积增大有关 相似文献
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The Concept of Record in Interactive, Experiential and Dynamic Environments: the View of InterPARES*
This article presents the concept of electronic record as articulated by the first phase of the InterPARES (International research on Permanent Authentic Records in Electronic Systems) Project (1999–2001) and discusses it in light of the findings of the second phase of the Project (2002–2006). While InterPARES 1 focused on records produced and/or maintained in databases and document management systems, InterPARES 2 examined records produced and/or maintained in interactive, experiential and dynamic environments. The authors describe the characteristics of these environments and of the entities found in them in the course of case studies conducted on systems used for carrying out artistic, scientific and e-government activities, and propose the new concept of record that InterPARES 2 is eleborating, which expands on that formulated by InterPARES 1.The authors would like to thank InterPARES 2 research assistant Randy Preston for his careful editing and constructive criticisms. Some of his suggestions have been incorporated in the text of this article. 相似文献
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This study examined two levels of media agenda effects on aggregatepublic opinion from different news sources. The effects wereinvestigated immediately and cumulatively. Content analysisdata from the 2000 U.S. presidential election coverage by fournational news organizations were related to the Gallup pre-electionpoll standings of each candidate. Regression analyses foundthat both the salience of a candidate and the salience of theattributes of a candidate cumulatively, but not immediately,influenced his standing in the polls. An analysis of news sourcessupported the finding that the two levels of agenda-settingeffects seemed mostly cumulative rather than immediate. Newsfrom different sources, however, tended to have effects of differentdegrees and sometimes different directions on candidate pollstandings. Cumulative effects of candidate salience on aggregateopinion change were found for non-partisan and neutral newssourcesreporters, poll reporting and public documentswhereasthe effects of candidate attribute salience mostly came frompartisan sourcesthe candidate himself and members ofthe competing political party. Possible political implicationsof these findings are discussed. 相似文献
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Cyberbullying is an increasingly common experience that produces psychosocial consequences for targets. Interventions encouraging bystanders to support targets of cyberbullying are limited by a lack of focus on what to communicate. This study considers supportive messages that emphasize emotional comfort, attributions of responsibility, and beliefs that people can change as relevant to this context, and it examines how perceptions of messages differ based on whether support providers have or lack experience with cyberbullying. We extend research on the indirect effects model of supportive communication by randomly assigning participants (N?=?304), who self-identify as targets of cyberbullying, to message and source conditions and assessing their perceptions of messages, providers, and outcomes. Impressions of messages mediate their influence on outcomes, and the experiential similarity of support providers moderates these effects. Certain messages, notably those contending that bullies can change, are less effective when delivered by sources who lack experience with bullying. 相似文献
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Stacy L. Young Manuel D. Pulido Catherine F. Brooks 《Communication Research Reports》2018,35(2):172-177
This study extends instructional communication research on extra-class communication (ECC) by presenting an integrative analysis comparing the explanatory utility of student- and instructor-oriented reasons for student engagement in frequent ECC. Results from 495 college students suggested that student-oriented reasons, specifically the relational and functional student motives, were the only significant, positive predictors of students’ perceptions of frequent ECC engagement. Other student motives (excuse making, participation, sycophancy) and perceptions of instructor approachability did not significantly predict perceived frequency of ECC engagement. 相似文献
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Caty Borum Chattoo Patricia Aufderheide Kenneth Merrill Modupeola Oyebolu 《广播与电子媒介杂志》2018,62(3):495-513
Where are diverse makers and subjects most likely to be found in U.S. TV documentary? This study compares commercial and public TV series, and also anthology formats (“authorial” series) and executive-produced formats. A content analysis for characters and makers showed that public TV authorial series are more diverse than either commercial or other public TV series. Independent documentaries have diversity value both in commercial and public TV settings. 相似文献
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