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101.
In 5 experiments with 265 male Wistar albino rats, production of lesions in the brain dopamine (DA) system by intraventricular injection of 6-hydroxydopamine (6-OHDA) resulted in increased responses to subcutaneous apomorphine (0.5 mg/kg) and reduced responses to methamphetamine (0.15 mg/kg). It also made Ss increase responding to intracerebroventricular (icv) cholecystokinin octapeptide (CCK-8; 0.5–2 μg) and reduce responding to cholecystokinin tetrapeptide (CCK-4; 0.5–2 μg). Response changes were quantified by measuring the level of general activity. Results indicate that DA dysfunction not only affected DA receptor sensitivity but also the sensitivity of the CCK system. The response to CCK-8 was partially blocked by a selective CCK-8 antagonist, proglumide (5 μg, icv), a result suggesting the involvement of the CCK-8 receptor system. Results indicate that manipulation of 1 neuronal system could induce sensitivity changes in another closely related system. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
The distortion of the fluorescence correlation function of a dye solution becomes larger with the increase in the excitation power, and eventually the parameters, such as the number of molecules and the diffusion time, obtained by the fluorescence correlation function systematically change. The most fundamental reason for this change is thought to be the distortion of the Gaussian excitation-detection field due to the saturation of the photocycle of the chromophore. The deviation from linearity of the fluorescence intensity causes the distortion of the fluorescence correlation function. Consequently, a smaller excitation power reduces the distortion and ensures an accurate measurement of the absolute value of these parameters. At the same time, the measurements at a fixed excitation power can be used to quantitatively determine the relative value of concentration and of the diffusion time. The deviation in the linearity of the fluorescence intensity and the deviation of the parameters show a high degree of correlation, and a 10% deviation of the intensity results in a prediction of a approximately 10% deviation in the number of molecules and a approximately 5% in the diffusion time. 相似文献
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The dead time of the detector significantly distorts the fluorescence correlation function of fluorescent particles in solution. This distortion of the correlation function is similar to the saturation effect of the correlation function in a high-power excitation region. The correlation amplitude is significantly reduced by the dead time. The deviations in the number of molecules and the diffusion time are empirically given by the deviation of the fluorescence intensity linearity. The empirical curves of the deviations can be applied to the systematic error estimation of the parameters. The proportionality of the number of molecules to the concentration of fluorophores is no longer maintained with a large dead time, although almost all of the proportionality of the diffusion time to the inverse diffusion constant remains. This fact makes the dead-time effect different from the saturation effect, which is due to photokinetics. In practice, these distortions can be reduced by use of a smaller excitation power in which the proportionality of the fluorescence intensity is maintained. 相似文献
105.
介绍了以 MESFET构成的微波放大器的 2种稳定化方法 ;在栅漏间或栅源间插入 RCL串联支路。分析了在这两种方法中 ,稳定化因子 K以及电路增益与 RCL参数的关系。 相似文献
106.
Ichiro Azuma Norio Kosaka Goro Iwamura Yoshiaki Marutani Hiroyuki Uemura 《Progress in Organic Coatings》1997,32(1-4):1-7
Acrylic oligomers containing siloxy groups were synthesized using trimethylsiloxyethyl methacrylate (TMSEMA) which have lower polarity and lower viscosity than those containing naked hydroxyl groups, and developed as high solid automotive top coatings by application of the crosslinking reaction between the siloxy groups and isocyanate groups or by the hybrid crosslinking reaction using the siloxy groups, epoxy groups, acid anhydride groups and hydrolyzable silyl groups. The hybrid crosslinked films show excellent acid resistance and scratch resistance. 相似文献
107.
Tetsuo Sato Hideyuki Abe Sumio Kawano Goro Ueno Kiyoji Suzuki Mutsuo Iwamoto 《Journal of the American Oil Chemists' Society》1994,71(10):1049-1055
The feasibility of near infrared (NIR) spectroscopy was examined for analyzing quality criteria or deterioration induces of
soybeans, such as the nitrogen solubility index (NSI), acid value, digestibility and percentage germination, as well as the
contents of their major constituents (moisture, oil and total nitrogen). Because all the criteria are closely related to yield
and quality of the final product, their rapid analysis is required for process control in the oil milling plant. NIR diffuse-reflectace
spectra were measured on ground samples in an InfraAlyzer 500 (Bran+Luebbe Co., Norderstedt, Germany). As for the major constituents,
the standard errors of prediction (SEP) were 0.34% (moisture), 0.24% (oil) and 0.067% (total nitrogen). There results show
the ability of NIR for analyzing these parameters, as many researchers reported previously. As for the other quality criteria,
the SEP values were 2.40 (NSI), 5.58 (digestibility), 0.29 (acid value) and 15.27 (germinatio percentage). Further, NIR analysis
for some of these criteria of the extracted residue and defatted soybeans was also examined, and almost the same level of
SEP values was obtained. Although it is still necessary to improve the accuracy, we concluded that the NIR method has the
feasibility to measure quality criteria for the purpose of process control in the plant in place of the time-consuming chemical
analysis that are conventionally used.
Part of this study was presented at 84th AOCS Annual Meeting & Expo, April 27, 1993, Anaheim, California. 相似文献
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