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排序方式: 共有1424条查询结果,搜索用时 15 毫秒
1.
H Neudeck M Joncic C Schuster S Bisson R Hildebrandt T Oney B Stiemer H Hopp R Graf 《Canadian Metallurgical Quarterly》1997,37(6):449-458
Nitric oxide (NO) acts as a modulator of neuronal transmission in mature neuronal systems, including the retina. Recently, NO has also been suggested to have a trophic function during development. We examined immunocytochemically the distribution of NO-producing cells in developing and transplanted rabbit retinas. An antibody detecting the neuronal isoform of its biosynthetic enzyme, nitric oxide synthase (NOS), was used on normal developing retinas [starting at embryonic day (E) 15] and on rabbit retinal transplants after various survival times (1-139 days after surgery). Weakly stained cell bodies were first observed in the proximal margin of the neuroblastic layer at E 29. Stained processes projecting towards a developing inner plexiform layer were also visible at this time point. Immunoreactive cells were located at later stages in the innermost part of the inner nuclear layer and in the ganglion cell layer, and are likely to correspond mainly to amacrine cells. NOS-labelled cells were also found in retinal transplants. The first NOS-labelled cells appeared, as in normal developing retinas, in ages corresponding to E 29 and were still detected in transplants corresponding to postnatal day 123. NOS-labelled cells were seen in areas between rosettes, where amacrine cells are located. NOS-labelled processes were at times seen to project for long distances, forming very distinct plexuses. NOS-containing amacrine cells thus appear both in the transplants and in developing retinas in the embryonic stages, long before synaptic function involving these cells can be expected, suggesting a role for NO not only in neuromodulation but also in retinal development. 相似文献
2.
Tested the ability of 4 adult male Sprague-Dawley rats to use odors in discrimination among littermates living as a group. Ss were trained in a Y-maze to discriminate the presence of a littermate from its absence. Results from transfer of training in 3 subsequent testing periods indicated that the animals were capable of distinguishing among individuals when relatedness and familiarity were held constant, that this ability was not due to training, and that performance was based solely on odor cues. Results suggest that laboratory rats exhibit odor sensitivities conmensurate with very complex social processes. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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General issues relating to the use of outcome and process data from the treatment of antisocial children to predict future childhood adjustment are examined. For outcome measures, it was assumed that variables based on direct observation of child behavior would provide a better predictor of long-term adjustment than would ratings by participant adults. Long-term adjustment measures consisted of police arrest and out-of-home placement data collected 2 years after treatment termination. Observation data collected at termination predicted future police arrest, but parent and teacher ratings did not. It was also hypothesized that measures of the processes thought to produce the changes in child antisocial behavior would serve as predictors of future adjustment. The data supported this hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Vanderby R. Jr. Masters G.P. Bowers J.R. Graf B.K. 《IEEE transactions on bio-medical engineering》1991,38(10):1040-1042
A device has been designed and fabricated to measure the cross-sectional area of soft connective tissues ex vivo. It consists of two displacement transducers; one sensing tissue thickness and the other sensing width. Outputs are recorded (via an analog to digital interface) using a personal computer. Numerical integration of a thickness versus width plot computes cross-sectional area. This plot also provides a quality check of acquired data. This device has been successfully used in biomechanical studies of rabbit patellar tendons, rat medial collateral ligaments, and dissected specimens of human fascia. 相似文献
6.
About Sulfur Containing Glycosides of Rape Seeds – Analysis by Thermospray Technique/Mass Spectrometry The HPLC is the method of choise for the estimation of glucosinolates occurring in rape seeds. But in comparison to GC a disadvantage is that the HPLC fractions can't be analyzed by MS directly. Such possibility is opened now with the thermospray technique. It allows to introduce the HPLC fractions immediately into the mass spectrometer system. Based on the first application of this technique to glucosinolates published by Mellon et al. (1987) the fundamentals of the thermospray technique/mass spectrometry are presented, the experimental details are explained and the characteristic ions of the thermospray mass spectra of 12 glucosinolates (desulfo derivatives) are discussed. The analytical performance of the method is examined also. 相似文献
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The performance and architecture of a high dynamic range camera (HDRC) chip and the conceptional advantages for its adaptation to image processing systems in traffic environments are discussed. The HDRC chip was developed with 64×64 pixels using a standard digital 1.2-μm CMOS technology. It is shown that the implementation proves the functionality and indicates the system performance of a highly dynamic range camera is feasible 相似文献
9.
L Zhao JB Helms B Brügger C Harter B Martoglio R Graf J Brunner FT Wieland 《Canadian Metallurgical Quarterly》1997,94(9):4418-4423
A site-directed photocrosslink approach was used to elucidate components that interact directly with ADP- ribosylation factor (ARF)-GTP during coat assembly. Two ARF mutants were generated that contain a photolabile amino acid at positions distant to each other within the ARF molecule. Here we show that one of the two positions specifically interacts with coatomer subunit beta both on Golgi membranes and in isolated coat protein complex type I (COPI)-coated vesicles. Thus, a direct and GTP-dependent interaction of coatomer via beta-coat protein complex (COP) with ARF is involved in the coating of COPI-coated vesicles. These data implicate a bivalent interaction of the complex with the donor membrane during vesicle formation. 相似文献
10.
D. Eckert A. Junod A. Bezinge T. Graf J. Muller 《Journal of Low Temperature Physics》1988,73(3-4):241-254
We have measured the low-temperature specific heat (1.3T20 K) and the dc magnetic susceptibility (100T250 K) of eight samples of the high-T
c
superconductor Y
x
Ba3–x
Cu3O7– (x=0.9, 1.0, 1.1) and of two samples of nonsuperconducting YBa2Cu3O6+. We have also performed specific heat measurements on the possible impurity phases: YBa3Cu2O7, Y2BaCuO5, CuO, and BaCuO2+x
. The superconducting samples all have a nonzero, sample-dependent linear term * and an upturn inC/T at very low temperature. We show that this anomalous behavior is at least partly due to the presence of a small amount (1%) of BaCuO2+x
impurity phase in the measured samples. This is evidenced by the correlation between * and the Curie component of the susceptibility, which is proportional to the amount of paramagnetic impurities. 相似文献