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11.
Isoforms p69 and p100 of 2'',5''-oligoadenylate synthetase induced differentially by interferons in vivo and in vitro 总被引:1,自引:0,他引:1
PL Witt I Marié N Robert A Irizarry EC Borden AG Hovanessian 《Canadian Metallurgical Quarterly》1993,13(1):17-23
There is no better place to test life-saving resuscitation interventions than in the prehospital setting. Patients rarely survive cardiac arrest if resuscitation techniques have failed before leaving the scene. Also, paramedics are usually very experienced in key initial resuscitative techniques, and they routinely operate under strict paramilitary protocol, resulting in better study compliance. In addition, the large study populations that are derived from emergency medical services (EMS) systems lead to faster study completion and statistically stronger data. Most important, by reinforcing standardized care, rigidly scrutinized trials improve patient care, regardless of the effect of the study intervention. The success of productive EMS research centers requires routine communication between hospital and EMS administrators and their medical directors, designation of mutually acceptable data collectors who guarantee confidentiality, reciprocal exchange of study data provided as educational seminars to the hospitals, commitments to support the budget requests of an EMS program and appropriate system modifications, inclusion of EMS personnel in study design from the very beginning, prospective education of the medical community and media before protocol implementation, an authoritative grassroots medical director, and a paramedic supervisor system. 相似文献
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T Tillmann K Kamino C Dasenbrock H Ernst M Kohler G Morawietz E Campo A Cardesa L Tomatis U Mohr 《Canadian Metallurgical Quarterly》1997,49(3-4):197-200
An experiment using 4279 CBA/J mice of two generations was carried out to investigate the influence of parental preconceptual exposure to X-ray radiation or to chemical carcinogens. Microchips were implanted subcutaneously in the dorsolateral back for unique identification of each animal. The animals were kept for lifespan under standard laboratory conditions. In 36 mice a circumscribed neoplasm occurred in the area of the implanted microchip. Females were significantly more frequently affected than male mice. An influence of age or different treatment on the s.c. tumour incidence in two mice generations could not be observed. Macroscopically, firm, pale white nodules up to 25 mm in diameter with the microchip in its center were found. Microscopically, soft tissue tumours such as fibrosarcoma and malignant fibrous histiocytoma were detected. 相似文献
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Ernst L.J. Hinman W.L. Quam D.H. Thorp J.S. 《Power Delivery, IEEE Transactions on》1992,7(4):1834-1852
The authors describe the relaying concepts of charge comparison. Charge comparison is a new transmission line protection system. It is a form of current differential relaying. Charge comparison largely resolves the traditional problems of current differential relaying of transmission lines, which are that protection is lost if a channel fails, a large channel capacity is required, and precise channel delay compensation is required. This technique is suitable for the protection of two- or three-terminal AC transmission lines, of all lengths and voltage levels, with or without series of shunt compensation, with three-hole or single-pole tripping 相似文献
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E Ernst 《Canadian Metallurgical Quarterly》1995,7(4):259-263
Complementary therapies are frequently used by cancer patients, yet the area is a minefield of hazards and hopes. A distinction between cure and care seems helpful. There are no effective complementary cures and most options that are promoted carry a distinct and, in certain cases, fatal risk. Complementary cancer care is more acceptable and there are options that can be shown to ease suffering. Vis a vis the popularity of complementary cancer treatments, the lack of scientific evidence for most therapies seems unacceptable. The call for more rigorous research is loud and clear. 相似文献
20.
HOW EVOLUTIONARY IS SCHUMPETER'S THEORY OF ECONOMIC DEVELOPMENT? 总被引:1,自引:0,他引:1
Ulrich Witt 《Industry and innovation》2002,9(1):7-22
The generic features of an evolutionary theory which are identified in the conceptional discussion of the present paper can be shown to be present already in Schumpeter's 1912 work, The Theory of Economic Development . None the less, it is argued that Schumpeter fell short of a level of generality by which he would have succeeded in providing a true foundation for evolutionary economics. The reason is his eagerness--very clearly visible in the "lost" seventh chapter--to align his theory with the economic reasoning of contemporary "pure" economic theory that was moulded in an equilibrium-oriented heuristic and the methodology of comparative statics. Schumpeter's conception--which, in opposing the idea of borrowing from Darwinian thought, he called "development"--is rather a special theory of the unsteady capitalist growth process passing through booms and crises. Throughout all of Schumpeter's writings the notion of development is therefore closely related to the business cycle phenomenon. The paper argues that this special framing implies not only some arbitrary hypotheses which are difficult to accept in an evolutionary interpretation, but also some limitations in his understanding of (what he refused to call) economic evolution, particularly with respect to its driving forces. 相似文献