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101.
GR Stewart Y Zhu W Parredes TI Tree R Guderian JE Bradley 《Canadian Metallurgical Quarterly》1997,65(1):164-170
The concentration and affinity to concanavalin A (ConA) of plasma alpha 1-acid glycoprotein (AGP) and AGP levels in extracts of liver tissues were investigated in specific-pathogen-free chickens infected with the highly virulent HPS-2 strain or virulent reference GBF-1 strain of infectious bursal disease virus. The plasma AGP value in uninfected control 3- to 7-wk-old chickens was 161.8 +/- 25.8 micrograms/ml (mean +/- SD), and ConA-unreactive and ConA-reactive AGP comprised 47% and 63% of total AGP. Increases in AGP levels in plasma and liver extracts were observed in both the HPS-2 and the GBF-1 groups, although albumin levels decreased. The plasma AGP values were higher in the HPS-2 group than in the GBF-1 group through the experimental period. In the HPS-2 group, ConA-reactive AGP reached levels 6.8-fold greater than control values and comprised 80% of total AGP at 4 days post-inoculation. In the lipopolysaccharide group, a great increase in ConA-reactive AGP was observed. 相似文献
102.
Praveen K. Sekhar Jie Zhou Matthew B. Post Leta Woo William J. Buttner William R. Penrose Rangachary Mukundan Cortney R. Kreller Robert S. Glass Fernando H. Garzon Eric L. Brosha 《International Journal of Hydrogen Energy》2014
In this article, the independent testing and validation of a packaged, electrochemical prototype hydrogen sensor at the National Renewable Energy Laboratory (NREL) is reported. Custom electronics were developed to be compatible with the data acquisition system at NREL. The specialized hydrogen sensor-testing laboratory at NREL used a variety of standardized test protocols to assess sensor performance. The system controlled and monitored humidity, pressure, and hydrogen gas concentration and introduced interference gases such as methane, carbon dioxide, carbon monoxide and ammonia. 相似文献
103.
KR Solomon EA Kurt-Jones RA Saladino AM Stack IF Dunn M Ferretti D Golenbock GR Fleisher RW Finberg 《Canadian Metallurgical Quarterly》1998,102(11):2019-2027
Septic shock induced by lipopolysaccharide (LPS) triggering of cytokine production from monocytes/macrophages is a major cause of morbidity and mortality. The major monocyte/macrophage LPS receptor is the glycosylphosphatidylinositol (GPI)-anchored glycoprotein CD14. Here we demonstrate that CD14 coimmunoprecipitates with Gi/Go heterotrimeric G proteins. Furthermore, we demonstrate that heterotrimeric G proteins specifically regulate CD14-mediated, LPS-induced mitogen-activated protein kinase (MAPK) activation and cytokine production in normal human monocytes and cultured cells. We report here that a G protein binding peptide protects rats from LPS-induced mortality, suggesting a functional linkage between a GPI-anchored receptor and the intracellular signaling molecules with which it is physically associated. 相似文献
104.
David C. Post Robert E. Page Jr. Eric H. Erickson Jr. 《Journal of chemical ecology》1987,13(3):583-591
When placed in a small observation arena with workers, most young virgin honeybee queens released fecal (hindgut) material during agonistic interactions with workers and with each other. On release of this material, workers moved to the sides of the arena and groomed themselves. Bioassays of virgin queen fecal material demonstrated that it contains pheromone that repels workers and stimulates grooming behavior. Pheromone was present only in the feces of virgin queens that were more than 24 hr old and less than 2 weeks old. Feces of 2- to 4-day-old workers and virgin queens more than 2 weeks old did not elicit an avoidance response by workers. Moreover, the feces of young virgin queens had a strong fragrance, while that of older queens had a rancid odor and that of young workers had no detectable odor. 相似文献
105.
GR Login M Aoki M Yamakawa LO Lunardi EC Digenis N Tanda LB Schwartz AM Dvorak 《Canadian Metallurgical Quarterly》1997,45(10):1379-1391
The subcellular events responsible for release of mediators by mast cells may help to clarify roles for mast cells in health and disease. In this study we show that the granule-associated protease chymase is also within cytoplasmic vesicles in appropriately stimulated rat peritoneal mast cells. Rat peritoneal mast cells were recovered before or 1-10 sec after exposure to the secretogogue compound 48/80 (10 micrograms/ml) and then were examined by radioimmunoassay to quantify histamine release or were processed, using routine methods for postembedding immunoelectron microscopy, to identify the subcellular localization of chymase. In comparison to unstimulated cells, compound 48/80 stimulated cells in two independent experiments showed an increase (15%, 28%) in the surface area of the cell and a decrease (12%, 6%) in the surface area of the total granule compartment before degranulation channel formation. These global cellular changes occurred in a background of transient but significant (p < 0.01) increases in the area and number of chymase-immunoreactive vesicles per microns2 cytoplasm. These changes were detectable at 5 or 7 sec after stimulation with compound 48/80 but returned to near prestimulation levels by 9 or 10 sec after addition of compound 48/80 (total cumulative histamine release was 28% by 8 sec and 47% by 14 sec). These observations suggest that vesicles participate in the early stages of regulated secretion of chymase from rat peritoneal mast cells. 相似文献
106.
107.
108.
GE Duncan SS Moy DJ Knapp RA Mueller GR Breese 《Canadian Metallurgical Quarterly》1998,787(2):181-190
Several lines of evidence suggest the molecular and functional entity of muscarinic M1 receptors in mammalian heart. We have reported that acetylcholine (ACh) reduces the maximum upstroke velocity of action potential (Vmax) through activation of muscarinic M1 receptors, which is followed by a muscarinic M2 receptor-mediated increase. The present study sought to determine whether activation of beta-adrenergic receptors modulates the muscarinic M1 and M2 receptor-mediated effects on Vmax in isolated mouse right atria. Intracellular recordings of spontaneous action potential were done using the conventional glass microelectrode technique. Isoproterenol (3 nM) completely antagonized ACh (5 microM)-induced reduction in Vmax. The antagonism was accompanied by a subsequent increase in Vmax. Propranolol (0.3 microM) abolished the effects of isoproterenol on ACh-induced changes in Vmax. Isoproterenol antagonized McN-A-343 (4-(m-chlorophenyl-carbamoyloxy)-2-butynyltrimethylammonium chloride) (300 microM, a muscarinic M1 receptor agonist)-induced reduction in Vmax. Oxotremorine (0.03 microM), a muscarinic M2 receptor agonist, did not affect Vmax by itself, but significantly increased it in the presence of 3 nM isoproterenol. The effects of isoproterenol were mimicked by cholera toxin (100 nM, 1 hr), a Gs-protein activator, and forskolin (10 nM), a direct activator of adenylyl cyclase. H-89 (N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulphonamide++ +, 1 microM), a selective protein kinase (PK)-A inhibitor, abolished the antagonism by isoproterenol of ACh-induced reduction in Vmax. The present results suggest that activation of the beta-adrenergic-Gs-adenylyl cyclase system antagonizes ACh-induced reduction (muscarinic M1-mediated) and potentiates the subsequent increase (muscarinic M2 receptor-mediated) in Vmax. The beta-adrenergic antagonism of ACh-induced reduction in Vmax may involve cross-talk between PK-A and PK-C signaling pathways. 相似文献
109.
A Lange M Walayat CM Turnbull P Palka P Mankad GR Sutherland MJ Godman 《Canadian Metallurgical Quarterly》1997,78(4):382-389
The properties of chemically cured and light-cured composite resins were recorded at baseline and at intervals over seven years, while the materials were exposed to controlled storage conditions as well as to various conditions typical of clinical situations. For chemically cured resins in clinical conditions, mechanical properties decreased, and working and setting times increased over four years; if refrigerated (controlled), properties remained constant past seven years. For light-cured resins, test results were constant over the entire seven-year test period regardless of storage conditions. An accelerated aging protocol was developed to allow for the evaluation of the relative storage stability of new and similar materials. 相似文献
110.
Kendall Richard Carver Jeffrey C. Fisher David Henderson Dale Mark Andrew Post Douglass Rhoades Jr. Clifford E. Squires Susan 《Software, IEEE》2008,25(4):59-65
Computational science is increasingly supporting advances in scientific and engineering knowledge. The unique constraints of these types of projects result in a development process that differs from the process more traditional information technology projects use. This article reports the results of the sixth case study conducted under the support of the Darpa High Productivity Computing Systems Program. The case study aimed to investigate the technical challenges of code development in this environment, understand the use of development tools, and document the findings as concrete lessons learned for other developers' benefit. The project studied here is a major component of a weather forecasting system of systems. It includes complex behavior and interaction of several individual physical systems (such as the atmosphere and the ocean). This article describes the development of the code and presents important lessons learned. 相似文献