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101.
WC Parris BW Johnson MK Croghan MR Moore A Khojasteh RF Reder RF Kaiko BJ Buckley 《Canadian Metallurgical Quarterly》1998,16(4):205-211
1. We have studied the effects of muscarinic cholinoceptor agonists and subtype-preferring antagonists on the isometric contraction of smooth muscle strips from dog prostate. 2. Acetylcholine and carbachol induced contraction of prostate strips from the peripheral zone, ('the capsule'). Bethanechol contracted the tissue but not at lower doses. McN-A-343 and oxotremorine-M showed the same effects. 3. Blocking alpha- and beta-adrenoceptors with phentolamine and propranolol, respectively, did not modify carbachol-induced contractions. 4. The nicotinic receptor blocker, hexamethonium (10(-6)-10(-4) M) did not affect the contractile response evoked by a single dose of carbachol (10(-5) M), whilst the muscarinic receptor antagonist, atropine (10(-11)-10(-9) M), inhibited it in a competitive manner. 5. The muscarinic M1 (pirenzepine), M2 [AF-DX 116, himbacine (M2/M4) and methoctramine], M3 (HHSID and f-F-HHSID), and putative M4 (tropicamide) antagonists reduced significantly the carbachol-induced contractions. The pIC50 values were: atropine (10.01) > himbacine (8.3) > methoctramine (7.85) > AF-DX 116 (7.60) > HHSID (7.21) > p-F-HHSID (7.10) > pirenzepine (7.30) > tropicamide (7.00). 6. The antagonist profile indicates that an predominant M2 receptor subtype could mediate the muscarinic contraction in the canine prostate. 相似文献
102.
103.
This article discusses a longitudinal study of change in disruptive behaviors among nursing home residents treated with neuroleptics compared with those not treated with neuroleptics. Observations were made of 201 participants on admission to and after 1 year in eight skilled nursing facilities. Nine disruptive behaviors were measured using the Psychogeriatric Dependency Rating Scale with nursing assistants. Neuroleptic use was documented from medication records. Odds ratios are reported for the association of behavior at baseline and use of neuroleptics on nine problem behaviors. For those who received neuroleptics during the year, there was greater change in both developing and resolving disruptive behaviors than for those not receiving neuroleptics. For both groups, restless or pacing behavior and belligerent behavior manifested by refusing instructions changed the most, both in developing and in apparently resolving. Our results show that change in disruptive behaviors occurs among nursing home residents regardless of neuroleptic use, but it occurs more frequently among those who receive neuroleptic medication. Knowledge of which disruptive behaviors are most likely to resolve or develop is important in training nursing home staff to cope with the behaviors as well as in planning interventions that may modify such behaviors. 相似文献
104.
A simple extension to the staircase FDTD algorithm yielding accurate subcell models of flat metal walls and corners is presented. Electric field nodes on the edges of staircase models of perfect electric conductors are replaced by values obtained using interpolation or analytic continuation into the metal. The algorithm is validated by computing the resonant frequencies of cavities 相似文献
105.
Strength and electrical conductivity of deformation-processed Cu-15 Vol Pct Fe alloys produced by powder metallurgy techniques 总被引:16,自引:0,他引:16
G. A. Jerman I. E. Anderson J. D. Verhoeven 《Metallurgical and Materials Transactions A》1993,24(1):35-42
Powder metallurgical techniques have been employed to prepare the precursor billets in the preparation of Cu-15 vol pct Fe
alloys by deformation processing. It has been demonstrated that by (1) using high-purity gas-atomized Cu powders blended with
commercial high-purity Fe powders and (2) controlling the time/temperature processing conditions within specific limits, it
is possible to produce Cu-Fe deformation-processed alloys with strength/conductivity properties matching those of Cu-Nb, Cu-Ta,
and Cu-Cr alloys. These properties are significantly superior to the best commercial alloys.
formerly with the Department of Materials Science and Engineering and Ames Laboratory, Iowa State University
This article is based on a presentation made in the symposium “High Performance Copper-Base Materials” as part of the 1991
TMS Annual Meeting, February 17–21, 1991, New Orleans, LA, under the auspices of the TMS Structural Materials Committee. 相似文献
106.
107.
Anderson Nicole D.; Craik Fergus I. M.; Naveh-Benjamin Moshe 《Canadian Metallurgical Quarterly》1998,13(3):405
Four studies examined the effects of divided attention in younger and older adults. Attention was divided at encoding or retrieval in free recall (Experiment 1), cued recall (Experiments 2 and 3), and recognition (Experiment 4). Dividing attention at encoding disrupted memory performance equally for the two age groups; by contrast, for both age groups, dividing attention at retrieval had little or no effect on memory performance. Secondary task reaction times (RTs) were slowed to a greater extent for the older adults than for the younger adults, especially at retrieval. Age-related differences in RTs costs at retrieval were largest in free recall, smaller in cued recall, and smallest in recognition. These results provide evidence for an age-related increase in the attentional demands of encoding and retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
The insulin-like growth factor (IGF) signaling system includes the growth factors and their cell surface receptors, along with circulating IGF binding proteins (IGFBPs) that may alter and modulate the action of these neurotrophic hormones. These IGFBPs, along with IGFs and receptors, have been detected in various tissues including the brain. In this study, using polyclonal antibody to human IGFBP-1 or bovine IGFBP-2, we found that mouse muscle extracts contain similar-sized proteins that cross-react with these antibodies on Western immunoblots. After establishing that these antibodies reacted with the homologous murine IGFBPs, we performed immunocytochemistry to demonstrate the localization of IGFBP-1 at the neuromuscular junction, a model nicotinic, cholinergic synapse, as well as within intramuscular nerves. IGFBP-2, a distinct macromolecule, is present on the surface of muscle fibers and is not present within synapses or nerves. 相似文献
109.
Hobbie KA Peterson ES Barton ML Waters KM Anderson KA 《Journal of laboratory automation》2012,17(4):275-283
Large collaborative centers are a common model for accomplishing integrated environmental health research. These centers often include various types of scientific domains (e.g., chemistry, biology, bioinformatics) that are integrated to solve some of the nation's key economic or public health concerns. The Superfund Research Center (SRP) at Oregon State University (OSU) is one such center established in 2008 to study the emerging health risks of polycyclic aromatic hydrocarbons while using new technologies both in the field and laboratory. With outside collaboration at remote institutions, success for the center as a whole depends on the ability to effectively integrate data across all research projects and support cores. Therefore, the OSU SRP center developed a system that integrates environmental monitoring data with analytical chemistry data and downstream bioinformatics and statistics to enable complete "source-to-outcome" data modeling and information management. This article describes the development of this integrated information management system that includes commercial software for operational laboratory management and sample management in addition to open-source custom-built software for bioinformatics and experimental data management. 相似文献
110.
Loss of precious metals from a Pt-10 wt% Rh alloy was studied at 1300° C in refractory oxides and fused quartz environments. After 60 and 150 h annealings, samples exposed to gaseous environments showed significant weight loss. The surface was attacked and characterized by micron-sized pits, as well as river-like striations. The pits were found to be enriched with silicon and/or aluminium depending upon the heating environment. Laser Raman microprobe identified that the major compound formed in the pits is -cristobalite.Direct solid state contact of Pt-Rh with Al2O3 and SiO2 showed interactions between materials. The interaction was more extensive between Pt-Rh with SiO2 than with Al2O3. On the other hand, no evidence of interaction except pitting and striation was observed on Pt-Rh when exposed to a vapour environment.The presence of pits and striation patterns indicated that refractory oxides attacked Pt-Rh under atmospheric conditions, and gave rise to the weight loss. Calculation of weight loss by an oxidation mechanism shows one to two orders of magnitude lower value than the actual weight loss. A new loss mechanism is proposed and discussed in this article. 相似文献