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971.
VA Martynov IM Rosly? OV Kolobaeva VI Kolobaev NI Agapova AK Rachkov 《Canadian Metallurgical Quarterly》1996,68(11):40-44
In 63 children with severe meningococcal infection (MI) and meningitides of another origin red cell metabolism was studied: levels of ATP, ADP, AMP, ATP/ADP, ATP/AMP, energetic charge, 2,3-DPG, FAD, piruvate, lactate, activity of lactate dehydrogenase, piruvate kinase, glucose-6-phosphate dehydrogenase, glutatione reductase, Mg2+, Na+, K(+)-dependent ATPase. All the disease periods were characterized by combined pathobiochemical shifts of different degree typical for varying metabolic systems and correlating with the infection severity. The discussion covers pathogenetic and clinical significance of red cell metabolism shifts in patients with MI and purulent meningitides. 相似文献
972.
973.
Jidong Kang David S. Wilkinson Mike Bruhis Mukesh Jain Pei Dong Wu J. David Embury Raja K. Mishra Anil K. Sachdev 《Journal of Materials Engineering and Performance》2008,17(3):395-401
In this article, we study the Portevin-Le Chatelier (PLC) bands and their influences on strain localization and fracture in
continuous cast (CC) AA5754 aluminum sheets. Three types of tensile tests are conducted: (1) tensile samples are pulled directly
to fracture at 223 K, (2) tensile samples are pulled at 223 K to initiate diffuse necking followed by unloading and reloading
to fracture at room temperature, and (3) tensile samples are pulled at 223 K to localized necking and unloaded followed by
reloading to fracture at room temperature. Furthermore, in situ V-bending test coupled with deformation mapping using digital
image correlation is used to study damage at large strains. The results show that PLC bands detect favorable geometrical sites
for shear band initiation. The formation of shear bands precedes damage and damage is a consequence of shear band formation.
This article was presented at Materials Science & Technology 2007, Automotive and Ground Vehicles symposium held September
16-20, 2007, in Detroit, MI. 相似文献
974.
First metatarsal fractures are rare because of their thick size and shape. They are to be treated aggressively because of the prolonged disability associated with such fractures. Any injury to the first ray may drastically alter the pattern of normal gait and weight-bearing. Most of the literature regarding such fractures is anecdotal, and there is little in the way of scientific articles that investigate their management. The general consensus for treatment of closed, nondisplaced first metatarsal fractures is to use some form of plaster immobilization. Nevertheless, there is much variation in the literature concerning the length of time patients should be casted. Rigid internal fixation using AO techniques is preferred if open reduction is to be instituted. Long-term complications with first metatarsal fractures are attributed mostly to malunion in the sagittal plane, resulting in a nonplantigrade foot. 相似文献
975.
976.
977.
This work, using a numerical code PC-1D, describes the effects of surface and bulk recombination on the performance of p+n indium phosphide solar cells. It is shown that surface recombination velocity and minority carrier diffusion lengths play a dominant role in controlling the efficiency of p+n cells. In order to have an acceptable series resistance, a p+n cell must have an emitter that is thicker than a n+p cell emitter. Consequently the performance of a p+n cell is more sensitive to the front surface recombination velocity. Improved surface and bulk recombination parameters can lead to cell efficiencies in excess of 24% AMO at 25°C. 相似文献
978.
In order to potentially decrease the number of homicides and suicides that result from firearms, one must decrease the accessibility of guns. We describe three cases that were obtained from the Onondaga County Medical Examiners Office in New York that occurred between January 1990 to March 1993. In two suicides and a double homicide, firearms were quietly obtained from commercially manufactured locked gun cabinets by removing the door hinges, which were located on the outside of the cabinet, with a screwdriver. The incidence of obtaining firearms by this method is not known. No other similar cases are reported in the literature. Removing hinges that are placed on the outside of the cabinet may be a common method of obtaining firearms to commit either homicide or suicide in the home, but perhaps not recognized. More information is needed. If additional cases are identified, then prevention in terms of gun cabinet design, may save lives in the future. 相似文献
979.
980.