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991.
A computational method has been developed successfully to predict the developing flow and heat transfer to a power law fluid flowing in square, trapezoidal and pentagonal cross-section straight ducts. The governing three-dimensional equations are parabolized axially. An orthogonal body-fitted coordinate system is employed to handle any arbitrary simply-connected channel geometry. The transformed equations are discretized and solved by line SOR technique. The computer code is capable of handling various boundary conditions and incorporates variable fluid properties and viscous dissipation. Typical results are presented to demonstrate the applicability of the code developed.  相似文献   
992.
Steady laminar binary mixed convection flow along a vertical circular cone under the combined buoyancy effects of thermal and species diffusion is studied analytically. The analysis is confined to mass diffusion processes with low concentration levels. In the analysis the surface of the cone is assumed to be at a uniform temperature and uniform concentration. Numerical results for the local Sherwood number, local Nusselt number and local friction factor are presented. Representative temperature, concentration and velocity profiles are also shown. The analysis covers the diffusion of common gases and vapours into air. Considerations are given to the situations where the buoyancy forces assist and oppose the forced convection flow for various possible combinations of the thermal and species diffusion processes.  相似文献   
993.
Graft-versus-host disease (GvHD) includes inflammatory and/or fibrosing manifestations that may arise at various times after transplantation of any organ containing lymphoid cells. For the dermatologist, the importance of GvHD is real and current. Indeed, because it has become easier to perform bone marrow transplantation (EMT), the indications of BMT have become broader, making follow-up of patients receiving grafts a widespread practice. Nonetheless, GvHD remains a frequent complication of BMT and its principal target organ is the skin. Furthermore, recent innovations, such as grafting of umbilical cord blood and the mobilization of peripheral blood progenitor cells, will be the source of new questions concerning the development of GvHD under these conditions. Finally, because of its analogies with other spontaneous idiopathic skin diseases, GvHD constitutes a model that may lead to a better understanding of the pathophysiological features of these diseases. In this review, the cutaneous aspects of GvHD are emphasized.  相似文献   
994.
Selective antagonists to the Type 3 serotonin receptor (5HT3) in combination with corticosteroids are now considered the standard of care for the prevention of emesis from moderately to highly emetogenic chemotherapy. Here we address issues of optimal dose, schedule and route of administration of four currently available selectable 5HT3 antagonists. This paper utilizes an evidence based medicine approach to the literature regarding this class of drugs, emphasizing the results large, randomized, controlled trials to make formal recommendations concerning optimal use of this important new class of anti-emetic agents. We conclude that for each drug there is a plateau in therapeutic efficacy at a definable dose level above which further dose escalation does not improve outcome. Furthermore, a single dose is as effective as multiple doses or continuous infusion, and finally, emerging data demonstrate that the oral route is equally efficacious as the intravenous route of administration, even with highly emetogenic chemotherapy.  相似文献   
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alpha-Crystallins possess molecular chaperone properties and are one of the most abundant of the lenticular proteins. Posttranslational modifications of these proteins have been implicated as a possible etiology of human cataracts. This article will review current knowledge concerning the effects of known posttranslational modifications upon the molecular chaperone properties and aggregation behavior of alpha-A and alpha-B crystallin. Based upon these effects, experimental approaches will be discussed that may be useful in the development of reagents that may selectively inhibit the cataractogenic process in the aging human lens.  相似文献   
997.
A large public service organization was concerned with protection of its customers against hazards associated with furniture tipping in public use concourses. Because no injury experience was available for analysis, hazard patterns for tipping accidents were developed from an observational study of public interaction with the furniture. For each hazard pattern, anthropometric models were used to find the probability of the furniture being safe from tipping, for different age and gender combinations. A safety criterion was developed from this modeling, and used to change the weights of some furniture items to resist tipping. These modifications have now been implemented and are in widespread use. Implications for broader application of these models to the development of valid tipping standards for furniture are discussed.  相似文献   
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