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1.
The neural mechanisms to reflex dilation elicited by electro-acupuncture stimulation were investigated in anesthetized rats. Two needles, with 160 microns diameter and about 5 mm apart, were inserted into the skin and underlying muscle of a hindpaw. Repetitive 20 Hz, 0.5 ms electrical pulses at various intensities were used for stimulation for 30s. The pupil size was magnified about 44 times via a microscope and was continuously recorded on a videotape. Electro-acupuncture stimulation at more than 0.5 up to 6 mA induced stimulus intensity-dependent pupil dilation. These responses were abolished by the severance of the sciatic and saphenous nerve of the stimulated hindlimb. Compound action potentials were recorded from the distal cut end of the tibial of a saphenous nerve following electro-acupuncture stimulation of the hindpaw. The mean threshold of the compound action potentials of the myelinated fibers in saphenous nerves was 0.18 mA, while that of unmyelinated fibers was 3.0 mA. The mean threshold of the compound action potentials of the myelinated fibers in the tibial nerve was 0.20 mA of unmyelinated fibers was 3.3 mA. Severance of bilateral trunks did not affect the response, while severance of the third cranial nerves abolished the responses. In conclusion, electro-acupuncture stimulation applied to the hindpaws of the anesthetized rats induced excitation of myelinated or of both myelinated and unmyelinated afferent fibers of the tibial and saphenous nerve, and involved a reflex response of pupil dilation through the third cranial parasympathetic efferent nerve.  相似文献   
2.
Thin film formation of graphite by chemical vapor deposition using 2-methyl-1,2′-naphthyl ketone as a starting material was carried out on Ni film substrates. On Ni films directly deposited on quartz glass, the graphite films were obtained when the Ni film thickness was above 1 000 Å and above 5 000 Å at 700 °C and 1 000 °C, respectively. Depositions on thinner Ni film substrates comprise amorphous carbon (a-C) or graphite tubes which was owing to the thermal coagulation of the Ni film into droplets. On the other hand, graphite film was obtained on the Ni film with thickness 10 Å when a-C was inserted between the Ni film and the quartz glass. The coagulation of the Ni film is considered to be avoided by inserting a-C layer.  相似文献   
3.
The present article reports the investigation of the effects of surrounding brightness on a visual search for three safety colors: red, orange, and yellow. Images of visual stimuli consisting of an array of colored circles placed on a large visual field (a visual angle of 40°) were displayed on an 80‐in. screen with a DLP projector. Experiment I examined the search efficiency under three levels of background luminance that were equivalent to the three target luminances. The results showed that the search efficiency for the orange target decreased as the number of distractors increased, under each of the background luminance levels, whereas the efficiency scarcely decreased for the red and yellow targets. Although a reduction in background luminance increased the search efficiency for the orange target, it is suggested that the effect of background luminance is smaller than the effect of the target color in search efficiency. Experiment II examined the search efficiency under three conditions of low levels of incident illuminance, which were matched with a linear regression to the luminance of color chips of safety colors measured twilight conditions. The results showed that the search efficiency for the orange target decreased as the number of distractors increased under each of the different illuminance conditions, whereas the efficiency scarcely decreased for red and yellow targets. Furthermore, as illuminance decreased, the search time for the orange target was more greatly impacted than for red or yellow. These results imply that the recognition of orange tends to be influenced by the surrounding brightness. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 400–409, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20152  相似文献   
4.
Selective epitaxial Si with a high arsenic concentration of 2.2×1019 atoms/cm3 was deposited at a high growth rate of 3.3 nm/min under atmospheric pressure. It was confirmed that this method had excellent selectivity and produced films having good crystalline quality, abrupt dopant profiles at the interfaces, and smooth surfaces. The growth mechanism is discussed in terms of the relationship between the effects of arsenic surface segregation and etching by hydrogen chloride.  相似文献   
5.
The levels of phosphatidylcholine hydroperoxide in serially cultured human fetal diploid fibroblasts at various population doubling levels were determined by high-performance liquid chromatography combined with chemiluminescence detections. This methodology utilizes a mixture of cytochromec and luminol as post-column hydroperoxide group specific luminescent reagents. The cellular hydroperoxide content increased with age from 0.34 to 27.72 pmol/106 cells. At the end of the cells'in vitro lifespan (51st population doubling level), the hydroperoxide content per 106 cells reached about 80 times the level found in cells of the 20th population doubling level. Supplementation of exogenous α-tocopherol to the culture medium prevented hydroperoxide accumulation, but did not extent the lifespanin vitro. The results indicate that substantial intracellular phospholipid hydroperoxide accumulation occurred in the course of aging of human fetal liploid fibroblasts.  相似文献   
6.
Wetting and brazing studies of sputtering-deposited, submicrometer thin film filler metal in an Ag—Cu—Ti/Al2O3 system were performed. The interfacial reaction layer between the filler metal and Al2O3 was investigated. It is possible to make a brazing joint even with a reaction layer of less than 100 nm thickness. Different types of interfacial reaction layers were observed when the Ti content in the filler metal was varied. The Cu—Ti—O system compounds were observed in the samples with high wetting capabilities, but not in the sample with low wetting characteristics. It was found that these compounds are substances that promote effective brazing.  相似文献   
7.
The polymerization of methyl methacrylate by tri-n-butylborane in the presence of amino acid esters was investigated. The binary systems of tri-n-butylborane and amino esters were found to be more effective for initiating the polymerization than tri-n-butylborane alone. Co-catalytic effects of amino acid esters were in the order: tyrosinate > glutamate > aspartate ? phenyl alaninate > serinate > glycinate. The rate of polymerization in a mixture of dimethylsulphoxide and toluene was proportional to the square root of the concentration of the initiator system, to the monomer concentration, and to the concentration of dimethylsulphoxide in the solvent. The overall energy of activation was estimated to be 4.6 kcal/mol for the tri-n-butylborane/methyl tyrosinate system. Copolymerization curves gave a typical free-radical character.  相似文献   
8.
To widen the vertical and horizontal angular ranges where the lens performs well, the off‐axis performance of a liquid crystal gradient index (LC GRIN) lens is analyzed by the combined simulation system of an LC director simulator and a ray‐tracing simulator. We found that the angular difference between an LC alignment direction and an electrode array direction of the LC GRIN lens is one of significant parameters, and detailed conditions of structure are established. The measurement result shows that the developed structure reduces the degradation ratio in a luminance profile from 61% to 3.2%. We have applied a user tracking system for the rotatable 3D display, equipped with a detection of a panel orientation and a face position. As a result, we have developed a rotatable 2D/3D tablet whose 3D viewing azimuth angle is over 30° in both landscape and portrait orientations.  相似文献   
9.
Cancer chemoprevention approaches use either pharmacological or dietary agents to impede, arrest or reverse the carcinogenic process. Although several agents have shown effectiveness against colon cancer, present intervention strategies provide only partial reduction. In this study, we utilized high-resolution endoscopy to obtain colon tumor biopsy specimens from Apc mutant mice before and after 2-wk sulindac intervention. To acquire information beyond genomics, proteome analysis using the ProteomeLab PF2D platform was implemented to generate 2-D protein expression maps from biopsies. Chromatograms produced common signature profiles between sulindac and nonsulindac treated samples, and contrasting profiles termed "fingerprints". We selected a double peak that appeared in tumor biopsies from sulindac-treated mice. Further analyses using MS sequencing identified this protein as histone H2B. The location of H2B in the 1(st) dimension strongly suggested PTM, consistent with identification of two oxidized methionines. While further studies on sulindac proteomic fingerprints are underway, this study demonstrates the feasibility and advantages of "real-time" proteomic analysis for obtaining information on biomarker discovery and drug activity that would not be revealed by a genetic assay. This approach should be broadly applicable for assessing lesion responsiveness in a wide range of translational and human clinical studies.  相似文献   
10.
For formation of β-FeSi2 using ion beam sputter deposition (IBSD) method, sputter etching (SE) followed by thermal annealing is effective substrate treatment to obtain highly (100)-oriented β-FeSi2 on Si(100). However, the best condition of these treatments are not yet known. In this work, the effect of SE together with annealing process on the orientation of the film is investigated. Prior to the deposition of Fe, the substrate is irradiated by Ne+ ions with various energy and fluence followed by thermal annealing at 1073 K for 60 min. The overall results show the most suitable SE condition using Ne+ ion on IBSD method is the energy of 1 keV with the fluence of 3.0×1019 ions /m2.  相似文献   
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