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21.
Nine schizophrenic patients participated in a study which explored whether EEG feedback techniques could effect changes in the EEG similar to those associated with neuroleptic-induced improvement. During five sessions, each patient was presented feedback signals which continuously refected the discrepancy between characteristics of the patient's EEG power spectral profile and spectral profile characteristics associated by past research with neuroleptic induced clinical improvement. Significant within-session changes were observed for two of three EEG power spectrum bands of interest. No significant session-to-session EEG changes were observed. The results suggest that the EEG of schizophrenics can be temporarily altered, using feedback techniques, in a way that mimics the EEG changes that have been shown to occur with neuroleptic induced clinical improvement.The authors are indebted to Turan M. Itil, John W. Fredrickson, Michael Madwed, and Irene B. Francis. Senior authorship is shared equally.  相似文献   
22.
Abstract: Phenylacetic acid, the major metabolite of phenylethylamine, has been identified and quantitated in rat brain regions by capillary column high-resolution gas chromatography mass spectrometry. Its distribution is heterogeneous and correlates with that of phenylethylamine. The values obtained were (ng/g ± SEM): whole brain, 31.2 ± 2.7; caudate nucleus, 64.6 ± 6.5; hypothalamus, 60.1 ± 7.4; cerebellum, 31.3 ± 2.9; brainstem, 33.1 ± 3.3, and the "rest," 27.6 ± 3.0.  相似文献   
23.
The reported selective serotonin Re-uptake Inhibitor Litoxetine was used as the starting point in the design of a range of potential SSRIs with high ease of synthetic accessibility. Preparation and subsequent optimization yielded a range of potent and highly selective SSRIs.  相似文献   
24.
One of the leading challenges for contemporary anthropology is to try to contribute to an understanding of the interaction between indigenous and exogenous socio‐cultural orders, especially at the frontiers of globalisation. Here I review three recent attempts to do so: (1) a model of structural transformation as developed by Marshall Sahlins; (2) a model of articulation as developed by James Clifford; (3) a model of ‘adoption’ proposed by Joel Robbins. As a test case for these models, I consider them in relation to some recent developments in local segmentary politics and verbal art in the Ku Waru region of Highland New Guinea. I show that all three models are in certain respects inadequate for understanding those developments, and offer some proposals as to what kinds of theory might be more adequate to the task.  相似文献   
25.
When expressed in Escherichia coli, a truncated form of phytochrome (oat PHYA AP3 residues 464-1129) self associates to form a series of products ranging in size from monomers to aggregates of greater than 20 subunits. When these same phytochrome sequences are coexpressed with the chaperonins GroEL and GroES, the truncated phytochrome migrates as a native-like dimer in size exclusion chromatography and no higher-order aggregates were detected. GroEL and GroES inhibition of phytochrome aggregation in E. coli presumably occurs via the suppression of folding pathways leading to incorrectly folded phytochrome.  相似文献   
26.
The photochemistry of the [(CpR)Mo(CO)(3)](2) molecules, where CpR = eta(5)-C(5)H(4)(CH(2))(2)C(O)NCH(3)(CH(2))(n)CH(3) (n = 3, 8, 13, and 18), was examined using femtosecond pump-probe transient absorption spectroscopy. The goal of this study was to investigate the importance of radical size and mass on the dynamics and efficiency of geminate radical-radical recombination. The femtosecond results demonstrated the lack of any size/mass dependence of the recombination efficiency. This finding contrasts with results from a prior study that did find a size/mass dependence using a steady-state photochemical technique. To explain these conflicting results, it is proposed that the femtosecond pump-probe results are a measurement of the efficiency of primary geminate recombination whereas the steady-state method results are a measurement of the sum of primary and secondary geminate recombination efficiencies. The size/mass dependence is evident in the latter because secondary geminate recombination is a slower diffusive recombination process and therefore depends on the steric properties of the radicals. Although the existence of primary and secondary recombination channels is often taken for granted, experimental differentiation of primary and secondary caging has proven to be difficult because it is not possible for a single experimental technique to span the entire timescale for recombination of a radical cage pair and adequately resolve these recombination pathways.  相似文献   
27.
Purine alkaloid catabolism pathways in young, mature and agedleaves of tea (Camellia sinensis L.) were investigated by incubatingleaf sections with 14C-labelled theobromine, caffeine, theophyllineand xanthine. Incorporation of label into CO2 was determinedand methanol-soluble metabolites were analysed by high-performanceliquid chromatography-radiocounting and thin layer chro-matography.The data obtained demonstrate that theobromine is the immediateprecursor of caffeine, which accumulates in tea leaves becauseits conversion to theophylline is the rate limiting step inthe purine alkaloid catabolism pathway. The main fate of [8-14C]theophyllineincubated with mature and aged leaves, and to a lesser extentyoung leaves, is conversion to 3-methylxanthine and onto xanthinewhich is degraded to 14CO2 via the purine catabolism pathway.However, with young leaves, sizable amounts of [8-14C]-theophyllinewere salvaged for the synthesis of caffeine via a 3-methylxanthine  相似文献   
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