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141.
Requests for monographs generated within an interlibrary loan network are analyzed for half-life statistics. It is suggested that demand represents use of the literature more completely than satisfied requests or circulation statistics. Demand in this study is characterized as either regional demand or statewide demand and is related to the level of the network where final processing of the request occurs. A negative exponential distribution is found to adequately characterize both levels of demand as a function of publication date for four subject categories. Corrected demand data is obtained by removing the growth rate of most of the available literature represented by American book publisher output. Based on over 10,000 interlibrary loan requests, negative exponential distributions describe the raw data as well as the corrected data. A shorter half-life was found for regional library demand (10.47 yr) than that found for statewide library demand (15.75 yr). Applying the correction factor to reflect the growth rate of the available literature tends to increase the half-life when compared to the raw data, and changes the ordering of subject classes with respect to ascending half-lives. 相似文献
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Margetic S 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(1):49-62
Inflammation and haemostasis are interrelated pathophysiologic processes that considerably affect each other. In this bidirectional relationship, inflammation leads to activation of the haemostatic system that in turn also considerably influences inflammatory activity. Such, the haemostatic system acts in concert with the inflammatory cascade creating an inflammation-haemostasis cycle in which each activated process promotes the other and the two systems function in a positive feedback loop. The extensive crosstalk between immune and haemostatic systems occurs at level of all components of the haemostatic system including vascular endothelial cells, platelets, plasma coagulation cascade, physiologic anticoagulants and fibrinolytic activity. During inflammatory response, inflammatory mediators, in particular proinflammatory cytokines, play a central role in the effects on haemostatic system by triggering its disturbance in a number of mechanisms including endothelial cell dysfunction, increased platelet reactivity, activation of the plasma coagulation cascade, impaired function of physiologic anticoagulants and suppressed fibrinolytic activity. The two examples of pathophysiologic processes in which the tight interdependent relationship between inflammation and haemostasis considerably contribute to the pathogenesis and/or progression of disease are systemic inflammatory response to infection or sepsis and acute arterial thrombosis as a consequence of ruptured atherosclerotic plaque. Close links between inflammation and haemostasis help explain the prothrombotic tendency in these two clinical conditions in which inflammation shifts the haemostatic activity towards procoagulant state by the ability of proinflammatory mediators to activate coagulation system and to inhibit anticoagulant and fibrinolytic activities. This review summarizes the current knowledge of the complex interactions in the bidirectional relationship between inflammation and haemostasis. 相似文献
146.
This paper investigates the determinants of R&D expenditure using a sample of UK listed companies with the highest spend from 2000 to 2005. We investigate the effect of corporate governance and ownership on R&D, using panel data. The results provide some evidence that more governance tends to depress R&D activity, a finding that is robust to whether a composite or disaggregated index of governance is used. One innovation of the paper is that we treat agency and finance effects interactively. The ownership stake of the CEO appears to be supportive for R&D. 相似文献
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Domestic violence against women is a significant social and public health problem that requires a varied social service response for abused women and their children. Increasingly, this service response includes online sources and resources. Using content analysis methods, we examined the Canadian provincial E-Government response to providing information to women exposed to domestic violence. Our overarching question was “if an abused woman went to her province’s government website for information and help and used common search strategies, what would she find?” 相似文献
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Amparo Núñez Andrés Felipe Buill Pozuelo Joaquín Regot Marimón Andrés de Mesa Gisbert 《Journal of Cultural Heritage》2012,13(1):103-106
Different techniques and tools currently exist to generate three-dimensional models of small elements, buildings and cities. Apart from being easier to interpret than two-dimensional drawings, these models facilitate data necessary for reconstruction projects, preservation or rehabilitation of the architectural or archaeological heritage. Traditional surveying only enables us to obtain discrete information of the characteristic lines that define each surface, edge, slope change etc. whereas work with massive capture techniques allows us to obtain continuous points of the surfaces. Photogrammetry or laser scanning combined with conventional photography provides information of the building in addition to its geometry. We carried out a review of the different techniques showing the advantages and disadvantages of each technique as well as the information that can be obtained by applying these techniques to the survey of the great Gate of Antioch in the town of Aleppo, declared a World Heritage Site by UNESCO in 1986, in Syria. 相似文献
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