共查询到20条相似文献,搜索用时 8 毫秒
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本文介绍了一套可在IBM PC(兼容)微机上运行的植物ms级荧光动力学数据采集和分析软件。本软件用C语言写成,具有汉化界面、菜单驱动、彩色人机对话窗口、操作简便、灵活,兼容性好等优点。本文着重讨论了本软件如何减少荧光动力学测量中的误差、在不过分占用内存的情况下扩大采样时间范围以及如何精确测量固定荧光(Fo)和偏转荧光(Fi)等问题。本软件和我们自行组装的植物ms级动力学荧光计——植物产量荧光计PFM-101型可广泛应用于农业、植物生态学及植物生理学的光合测量和研究。 相似文献
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介绍全自动膜片钳数据采集控制系统USB2.0接口的设计。该系统采用USB2.0控制器CY7C68013,实现了PC机和膜片钳放大器的数据传输。详细介绍了USB硬件接口、固件程序设计以及上位机应用程序的设计。 相似文献
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《Molecular & cellular proteomics : MCP》2020,19(7):1088-1103
Highlights
- •Rapid DIA-only library building with gas-phase fractionation.
- •Recommended DIA acquisition strategies with staggered windows and forbidden zones.
- •Optimized DIA instrument settings for several Thermo Orbitrap instruments.
- •Data analysis tutorial using open source DIA software.
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Functional magnetic resonance imaging (fMRI) is currently the standard method of evaluating brain function in the field of Cognitive Neuroscience, in part because fMRI data acquisition and analysis techniques are readily available. Because fMRI has excellent spatial resolution but poor temporal resolution, this method can only be used to identify the spatial location of brain activity associated with a given cognitive process (and reveals virtually nothing about the time course of brain activity). By contrast, event-related potential (ERP) recording, a method that is used much less frequently than fMRI, has excellent temporal resolution and thus can track rapid temporal modulations in neural activity. Unfortunately, ERPs are under utilized in Cognitive Neuroscience because data acquisition techniques are not readily available and low density ERP recording has poor spatial resolution. In an effort to foster the increased use of ERPs in Cognitive Neuroscience, the present article details key techniques involved in high density ERP data acquisition. Critically, high density ERPs offer the promise of excellent temporal resolution and good spatial resolution (or excellent spatial resolution if coupled with fMRI), which is necessary to capture the spatial-temporal dynamics of human brain function.Download video file.(101M, mp4) 相似文献
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Sidney J. Cutler 《The Western journal of medicine》1967,106(2):98-107
The End Results Group, sponsored by the National Cancer Institute, coordinates a national cooperative program for evaluating the results of cancer therapy. Three central tumor registries (in California, Connecticut and Massachusetts) plus nine individual hospital registries (in university hospitals) are participating in the program.During the period 1940-59, there was an encouraging increase in five-year survival rates among patients with carcinomas and sarcomas (solid tumors). Preliminary data for 1955-59 suggest that the upward trend is leveling off. A smaller absolute increase in five-year survival rates occurred among patients with lymphomas and leukemia. These increases in patient survival rates coincided with more frequent use of surgical operation for solid tumors and more frequent use of chemotherapy for lymphomas and leukemia. 相似文献
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基于USB数据采集器的膜片钳系统软件设计 总被引:1,自引:1,他引:1
为了控制新的基于USB总线的数据采集器进行膜片钳实验,设计和实现了能应用于Windows 2000/XP操作系统的膜片钳系统软件。软件运用面向对象程序设计方法和统一建模语言,实现了封接测试.电压门控和配体门控等实验模式。实验结果表明,该系统软件能够精确控制数据采集器进行高速数据采集,满足细胞生理实验的要求。 相似文献
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《Electromagnetic biology and medicine》2013,32(2):307-321
In some dynamic magnetic resonance imaging (MRI) applications, the sample is still, and only the signal intensity changes with time. For such cases, the keyhole imaging principle can be used. In standard keyhole imaging, a low-frequency image signal is acquired, using a limited number of phase-encoding steps, which correspond to the rectangular sampling region in the k-space center. However, such a region practically never coincides with the position of the k-space points, which carry the most relevant low-frequency image information. In this paper we propose an improved keyhole method, which allows dynamic acquisition of a low-frequency image signal from selected most relevant k-space points via fast imaging mechanisms. Dynamic data acquisition is executed in the presence of time-varying magnetic-field (MF) gradients after single sample excitation. Special care has been taken in the design of the gradient sequence to minimize gradient load. This improved keyhole imaging method has been considered theoretically and verified experimentally on a model system. 相似文献
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Dewey CF 《Biorheology》2002,39(3-4):541-549
This paper is presented as a summary and synthesis of the presentations at the conference entitled "Breaking Symmetry in Haemodynamics". As the accompanying papers will attest, there has been enormous progress in understanding the effects of fluid flow on the arterial endothelium and the consequential effects on the vessel wall. It is now clearly understood that the focal lesions found in atherosclerotic arteries are the product of asymmetrical flow and the resulting disturbed flow that occurs near arterial bifurcations and other selected points around the human vasculature. The flow in large vessels can now be determined accurately with MR and in vitro cast models. Although theory allows arterial flow to be characterized by asymmetry in time and space, our understanding of the processes that act to translate this asymmetry into pathology is becoming much more symmetric, or complete. The new frontiers of research in arterial flow are now translating to smaller scales, at the cellular level and below. 相似文献
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P. B. S. Fowler H. Ikram R. N. Maini A. R. Makey J. S. Kirkham 《BMJ (Clinical research ed.)》1969,1(5636):92-94
A patient with a sinus bradycardia and angina is described who was unable to increase his heart rate on vigorous exercise by more than a few beats. His severe angina was attributed to the bradycardia. Atrial pacing of his heart abolished his angina and increased his exercise tolerance. Circulatory changes at rest, on exertion, and with atrial pacing are described. The cause of angina in this patient is discussed. 相似文献
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Hormonal Contraception and the Risk of HIV Acquisition: An Individual Participant Data Meta-analysis
Charles S. Morrison Pai-Lien Chen Cynthia Kwok Jared M. Baeten Joelle Brown Angela M. Crook Lut Van Damme Sinead Delany-Moretlwe Suzanna C. Francis Barbara A. Friedland Richard J. Hayes Renee Heffron Saidi Kapiga Quarraisha Abdool Karim Stephanie Karpoff Rupert Kaul R. Scott McClelland Sheena McCormack Nuala McGrath Landon Myer Helen Rees Ariane van der Straten Deborah Watson-Jones Janneke H. H. M. van de Wijgert Randy Stalter Nicola Low 《PLoS medicine》2015,12(1)
BackgroundObservational studies of a putative association between hormonal contraception (HC) and HIV acquisition have produced conflicting results. We conducted an individual participant data (IPD) meta-analysis of studies from sub-Saharan Africa to compare the incidence of HIV infection in women using combined oral contraceptives (COCs) or the injectable progestins depot-medroxyprogesterone acetate (DMPA) or norethisterone enanthate (NET-EN) with women not using HC.ConclusionsThis IPD meta-analysis found no evidence that COC or NET-EN use increases women’s risk of HIV but adds to the evidence that DMPA may increase HIV risk, underscoring the need for additional safe and effective contraceptive options for women at high HIV risk. A randomized controlled trial would provide more definitive evidence about the effects of hormonal contraception, particularly DMPA, on HIV risk. 相似文献