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61.
62.
北京地区不同大豆品种异黄酮含量比较研究 总被引:1,自引:0,他引:1
异黄酮是大豆生长过程中自然产生的化学物质,被认为可以治疗和预防一些人类依赖激素的疾病.为比较北京地区生态条件下大豆品种间异黄酮含量的差异性,对53个品种种子中3种异黄酮(大豆苷元、染料木素和黄豆黄素)进行测定和分析.结果表明,品种间异黄酮含量存在较大多样性,大豆苷元为39.21~2 363.65 μg/g,染料木素为77.35~1 149.50 μg/g,黄豆黄素为0.0~51.30μg/g,3种异黄酮总量为146.73~2 845.60 μg/g.来自山西和山东品种的异黄酮含量显著高于其他地区的品种.异黄酮总量分别与大豆苷元和染料木素呈极显著正相关,而大豆苷元和染料木素之间没有互作.因此,可以利用高含量大豆苷元或染料木素材料选育高异黄酮品种. 相似文献
63.
OBJECTIVE: It is not clear whether obsessive-compulsive disorder (OCD) in the context of Tourette's syndrome (TS) is the same as that disorder found in patients with OCD alone. This study evaluated the severity and characteristics of the obsessive-compulsive symptoms in adult patients with OCD and TS compared to adult patients with OCD alone. METHOD: Thirteen subjects with both DSM-III-R TS and OCD and 13 subjects with OCD alone were recruited. Obsessive-compulsive severity was determined by using the Yale-Brown Obsessive Compulsive Scale. The Tourette Syndrome Association Unified Tic Rating Scale was administered to determine tic severity, and the adult version of the Attention Deficit and Hyperactivity Checklist was used to detect a history of childhood attention-deficit hyperactivity disorder (ADHD). RESULTS: Subjects with OCD alone had very few obsessions and compulsions that were not also experienced by subjects with both TS and OCD. In contrast, subjects with TS and OCD were significantly more likely to report obsessions involving nonviolent images, excessive concern with appearance, and need for symmetry. Touching, blinking or staring, and counting compulsions were also significantly more common in this group. Eight subjects with OCD and TS had a childhood history of ADHD, compared to none of the pure OCD subjects. CONCLUSION: There are subtle but definite differences in symptomatology of subjects with pure OCD compared to those with OCD and TS consistent with putative differences in pathophysiology between the 2 groups, i.e., abnormalities in the serotonergic system in OCD patients and serotonergic and dopaminergic abnormalities in those with OCD and TS. These observations may be consistent with genetic heterogeneity within both OCD and TS. 相似文献
64.
Miroslav Balog Viliam Vretenár Ivo Vávra Jiaming Zhang Martin A. Crimp L’udovít Kubičár Zoltán Lenčéš 《International Journal of Thermophysics》2009,30(6):1918-1930
Multifunctional cermets are being developed for a range of novel applications. The present paper deals with thermophysical
properties of electrically conductive SiC-based cermets. The cermets were prepared by in situ reaction using a two-step sintering
process. The thermophysical properties, namely, thermal conductivity, thermal diffusivity, and heat capacity, were measured
using the pulse transient technique. The microstructure and chemical composition of the samples were characterized by SEM
(scanning electron microscopy), TEM (transmission electron microscopy), STEM (scanning transmission electron microscopy),
and EDX (energy dispersive X-ray analysis) techniques. The observed thermophysical data were correlated with the observed
microstructures and chemical nature of the SiC-based cermets. 相似文献
65.
GV Matiushin VA Shul'man AI Balog SE Golovenkin AP Bezruk EA Ivanitski? OV Smirnova 《Canadian Metallurgical Quarterly》1998,70(6):47-50
AIM: To assess by means of transesophageal left atrial pacing the effectiveness of cordarone treatment for arrhythmias caused by re-entry mechanism. MATERIALS AND METHODS: Effectiveness of cordarone treatment was estimated in 25 patients with atrioventricular nodal tachycardia (AVNT) and in 33 patients with WPW syndrome and reciprocal atrioventricular tachycardia (RAVT) with frequent paroxysms of tachycardia 1-5 times per week. Transesophageal left atrial pacing (TELAP) was performed before antiarrhythmic treatment and on cordarone treatment day 14-18. Cordarone was given for two months in common regimen (the first 10 days--600 mg/day, the next 10 days--400 mg/day and then 200 mg/day). RESULTS: The first TELAP induced paroxysmal AVNT or RAVT in all the patients. According to the results of the second TELAP, all the patients were divided into three groups. Group 1 included 28 patients in whom the second TELAP was unable to induce tachycardia. All these patients had increased effective refractory period (ERP) of AV node and/or of accessory pathway (AP) values and a decreased Wenkebach point (WP) < 150/min during the second TELAP in comparison with the first TELAP. All these patients had no spontaneous paroxysms of T during the 3-month follow-up. Group 2 included 18 patients in whom the second TELAP induced AVT lasting < 30 seconds. 16 of these patients had tachycardia with less heart rate during the second TELAP in comparison with the first TELAP, 153 + (-) 8 bpm vs 188 + (-) 10 bpm, p < 0.001, respectively. Also, in these 16 patients we found an increase of values of ERP of AV node and/or AP > 360 ms and a decrease of WP < 150 bmp. 14 of these 16 patients had no spontaneous paroxysms of AVT and 2 patients had short episodes of AVT during the 3-month follow-up with effects of vagal manoeuvers. From 2 other patients of group 2 one had short episodes of spontaneous T and one had long episodes of tachycardia with effect of verapamil i.v. Group 3 included 12 patients in whom the second TELAP induced the same AVT as the first TELAP. Values of ERP of AV node and/or AP and WP during the first and second TELAP were not different. All of these patients had long spontaneous paroxysms of AVT during cordarone treatment day 14-18. The treatment was discontinued in all patients of group 3. CONCLUSION: Cordarone is effective in prevention of AVT. Negative results in provocation of AVT during TELAP after 14-18 days of cordarone treatment is a very specific predictor of cordarone treatment effectiveness. Provocation by TELAP of short episodes of AVT with reduced heart rate and higher values of ERP of AV node and AP and lowering of WP < 150 bpm may not predict ineffectiveness of cordarone in patients with AVT. Moreover, the majority of these patients had no spontaneous episodes of AVT. Provocation by TELAP during cordarone treatment of the same AVT episodes as before cordarone treatment is a very specific predictor of cordarone effectiveness. 相似文献
66.
A rapid prototyping software infrastructure for user interfaces in ubiquitous augmented reality 总被引:1,自引:0,他引:1
Recent user interface concepts, such as multimedia, multimodal, wearable, ubiquitous, tangible, or augmented-reality-based (AR) interfaces, each cover different approaches that are all needed to support complex human–computer interaction. Increasingly, an overarching approach towards building what we call ubiquitous augmented reality (UAR) user interfaces that include all of the just mentioned concepts will be required. To this end, we present a user interface architecture that can form a sound basis for combining several of these concepts into complex systems. We explain in this paper the fundamentals of DWARFs user interface framework (DWARF standing for distributed wearable augmented reality framework) and an implementation of this architecture. Finally, we present several examples that show how the framework can form the basis of prototypical applications. 相似文献
67.
Daqing Zhang Bela I. Sandor 《Fatigue & Fracture of Engineering Materials & Structures》1990,13(5):497-509
A thermoelasticity theory for damage in anisotropic materials is developed. This theory can be applied to evaluate the damage parameter D, the normalized effective mess density ρe/ρ, and the effective modulus Ee quantitatively in some metals and composites by incorporating the thermographic stress analysis method (TSA; also, SPATE method). The effective moduli due to fatigue damage and static loads in a glass fiber/epoxy laminate obtained by the TSA method are compared with the values measured by an extensometer. The correlation between the measurements using the two methods is very good. 相似文献
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70.
HfO2 films were deposited on silicon substrates by the oxygen-assisted decomposition of hafnium β-diketonates at temperatures in the range 400–550 °C. These films were characterized by using transmission electron microscopy, X-ray diffraction, electron microprobe analysis and measurements of dielectric and optical properties. It was found that the films were fine-grained (approximately 325 Å) nearly stoichiometric monoclinic HfO2. The films showed high resistance to most aqueous acids and bases. The deposits had a refractive index of 2.1 and an optical energy gap of 5.68 eV. The dielectric constant at 1 MHz was 22–25, and the dielectric strenght of the HfO2 films varied between 2 × 106 and 4.5 × 106 V cm?1. C-V measurements at 1 MHz indicated the presence of effective surface states which varied between 1.0 × 1011 and 6 × 1011 cmt?2 for films that were deposited at temperatures higher than 500 °C or that were annealed at above 750 °C if deposited at 400–450 °C. The VFB values were between ?0.6 and 0 V. The annealed films or films grown above 500 °C showed good bias-temperature stability. When positive bias and elevated temperatures were applied, the original C-V curve moved towards higher positive field values (0.2-0.5 V). After applying negative bias at elevated temperatures the C-V curved moved back in the direction of the original C-V curve. Measurements of the dependence of the current I on the electric field showed a dependence of I ∝ V2 over a wide range. 相似文献