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41.
GP Fontana 《Canadian Metallurgical Quarterly》1998,8(4):871-890
In a short period of time, tremendous progress has been made in the field of minimally invasive cardiac surgery. The goal of true "minimally invasive" cardiac surgery should be a totally thoracoscopic or transvascular procedure that allows a very short hospital stay and prompt patient recovery at acceptable costs. To accomplish this goal, efforts to miniaturize and refine instrumentation/cannulae/visualization and the development of innovative new techniques must be pursued. The concept of performing intracardiac repair of a variety of pathologies on the beating heart is under investigation and will require a new generation of technology, which will include through-blood imaging, such as blood displacement videoscopes, and task-specific instruments. Robotics may offer additional assistance in the performance of complex and fine maneuvers. 相似文献
42.
The acceptance of highly active antiretroviral therapy (HAART) among patients and health care providers has had a dramatic impact on the epidemiology and clinical characteristics of many opportunistic infections associated with human immunodeficiency virus (HIV). Previously intractable opportunistic infections and syndromes are now far less common. In addition, effective antibiotic prophylactic therapies have had a profound impact on the risk of patients developing particular infections and on the incidence of these infections overall. Most notable among these are Pneumocystis carinii, disseminated Mycobacterium avium complex, tuberculosis, and toxoplasmosis. Nevertheless, infections continue to cause significant morbidity and mortality among patients who are infected with HIV. The role of HAART in many clinical situations is unquestioned. Compelling data from clinical trials support the use of these therapies during pregnancy to prevent perinatal transmission of HIV. HAART is also recommended for health care workers who have had a "significant" exposure to the blood of an HIV-infected patient. Both of these situations are discussed in detail in this article. In addition, although more controversial, increasing evidence supports the use of HAART during the acute HIV seroconversion syndrome. An "immune reconstitution syndrome" has been newly described for patients in the early phases of treatment with HAART who develop tuberculosis, M avium complex, and cytomegalovirus disease. Accumulating data support the use of hydroxyurea, an agent with a long history in the field of myeloproliferative disorders, for the treatment of HIV. Newer agents, particularly abacavir and adefovir dipivoxil, are available through expanded access protocols, and their roles are being defined and clarified. 相似文献
43.
This paper describes a successful project using computer animation to teach the concepts of microprogramming to lower division computer science majors. The students write a simulator for the Mic-1 horizontal microcontroller described in the book Structured Computer Organization by Tanenbaum. The simulation is enhanced by the use of a graphical representation of the machine to animate the simulation. This creative use of computer animation enables the students to see the results of their simulation without having to write an extensive user interface. They can concentrate on implementing the instruction cycle, an activity that directly enhances their understanding of microprogramming and the conventional machine level. The XTango animation package is used, making the animation facility portable to any Unix system with an X display. The user interface and additional instructional material are available via the web 相似文献
44.
Zhang A Robbins PS Averill AL Weber DC Linn CE Roelofs WL Villani MG 《Journal of chemical ecology》2003,29(7):1635-1642
Hoplia equina LeConte (Coleoptera: Scarabaeidae: Melolonthinae) is a beetle pest of cranberry beds in Massachusetts. Larvae feed on the roots of the cranberry plant, reducing yield as well as vine density. The female sex pheromone was identified as 2-tetradecanone. There were eight compounds found in the airborne volatiles collected from females that elicited antennal responses from males. Of the eight compounds tested (nonanal, decanal, dodecanal, 2-dodecanone, 2-tridecanone, 2-tetradecanone, 2-pentadecanone, and 2-hexadecanone), 2-tetradecanone was the only one that attracted male beetles in the field. Combining any of the other seven antennally active compounds with 2-tetradecanone did not increase male capture. 相似文献
45.
Bryan Angela; Rocheleau Courtney A.; Robbins Reuben N.; Hutchinson Kent E. 《Canadian Metallurgical Quarterly》2005,24(2):133
The goal of this study was the exploration of distal effects of alcohol use on condom use. Criminally involved adolescents completed an initial measure of attitudes, beliefs, and prior behavior. Of the 300 who completed the initial measurement, 267 (89%) completed a behavioral assessment 6 months later. Analyses validated a theoretical model of condom use intentions and indicated that intentions and attitudes measured at baseline were significant predictors of condom use behavior 6 months later. Neither alcohol use nor alcohol problems moderated relationships among model variables or the influence of intentions and attitudes on behavior. The findings do not support a distal role for alcohol use in altering the cognitive correlates of condom use intentions and behavior among high-risk adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
W. B. Doriese K. M. Morgan D. A. Bennett E. V. Denison C. P. Fitzgerald J. W. Fowler J. D. Gard J. P. Hays-Wehle G. C. Hilton K. D. Irwin Y. I. Joe J. A. B. Mates G. C. O’Neil C. D. Reintsema N. O. Robbins D. R. Schmidt D. S. Swetz H. Tatsuno L. R. Vale J. N. Ullom 《Journal of Low Temperature Physics》2016,184(1-2):396-396
47.
Diet modification to alter the course of age-related cognitive decline is becoming increasingly important. Few observational findings suggest that dairy food intake may be positively related to cognitive function, but research in this novel area is limited. The aim of this study was to investigate whether dairy food intake is associated with cognitive function, before and after adjustment for cardiovascular, lifestyle and dietary factors. To do this, a cross-sectional analyses of a subset of the community-based Maine-Syracuse Longitudinal Study (MSLS) sample (N = 972) was undertaken. It was determined that participants who consumed dairy products at least once per day had significantly higher scores on multiple domains of cognitive function compared with those who never or rarely consumed dairy foods, adjusting for cardiovascular risk factors, lifestyle and dietary factors. Frequent dairy food intake is associated with better cognitive performance but underlying causal mechanisms are still to be determined. 相似文献
48.
ABSTRACTThis article accounts for how value in design research can be derived from knowledge exchange that occurs through the collaborative discourse of doing design. To demonstrate this point, the article details the arc and impact of a design research collaboration that extended over several years with design practitioners in the field of internet-connected devices. As a result of this ongoing collaborative work, a programmatic set of design ideals and intentions concerning how to construct a more transparent and ethical relationship with technology was shaped. We examine this sustained and transformative collaboration as a series of knowledge exchanges. Within each particular collaborative project, worldviews and knowledge are exchanged among design researchers and practitioners, enabling them to traverse ‘through practices’ of academic and professional design. To unpack these exchanges and how they built and fed into each other, the article examines how collaboration unfolded and produced value on two levels: first on the scale of the academics and practitioners directly involved in a project; and secondly on the scale of the larger international community of design practitioners concerned with Internet-connected devices, with whom we had shared our work. 相似文献
49.
50.
Deborah Robbins 《Journal of Architectural Education》2013,67(1):57-61
In the late 1950s the Bacardi Rum Corporation commissioned Ludwig Mies van der Rohe to design an office building in Mexico. Bacardi used the commission to shape its image as a sophisticated and cosmopolitan enterprise, as it reinvented itself in the aftermath of the Cuban Revolution. The Bacardi project serves as a case study of corporate patronage of modern architecture in Latin America, marking a moment when both the image and organization of Mies's architecture helped build a reliable, mainstream international brand. Paradoxically, Mies's Bacardi building would also become part of a “mix” of architectural commissions that would include emerging alternatives to International Style modernism. 相似文献