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排序方式: 共有96条查询结果,搜索用时 15 毫秒
1.
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
2.
Bacteriophage-resistant mutants of Bacillus thuringiensis with decreased virulence in pupae of Hyalophora cecropia 总被引:3,自引:1,他引:2
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Starting from a crystal-negative parental strain of Bacillus thuringiensis, we isolated certain bacteriophage-resistant mutants which showed decreased virulence in pupae of the cecropia moth (Hyalophora cecropia). These strains (class I mutants) were highly pleiotropic and showed resistance to seven or eight different phages, sensitivity to methicillin, and loss of flagella. They were also more sensitive to cecropia immune hemolymph in vitro. In addition, the export of at least three proteins was reduced. Revertants (class II mutants) were sensitive to phages, virulent, and resistant to penicillin derivatives. One class II mutant was a complete revertant in all properties examined. The other class II mutant was an incomplete revertant still susceptible to immune hemolymph and with repressed export of proteins. Virulence was not coupled to phage resistance as such or to lack of flagella because other mutants affected in these properties were virulent. Other factors which could be excluded as causes of virulence were production of extracellular protease and hemolysin. 相似文献
3.
Preacclimatization of men to heat by training 总被引:2,自引:0,他引:2
4.
Inga Sidén-Kiamos Guido Favia Dora Artiaco Giuseppe Saceone Maria Furia Lino C. Bolito Christos Louis 《Genetica》1993,92(1):43-53
The sequence determination of several genomic clones isolated from the Mediterranean fruitfly Ceratitis capitata identified the existence of opa-like repeats, often more than one being clustered in small chromosomal segments. These repeats have previously been shown to consist of stretches of tandemly reiterated glutamine-encoding residues, and they are found in multiple genes of several organisms. Most of the repeats described here are flanked or interrupted by stop codons in all reading frames and, thus, could not possibly be part of protein-coding sequences. Furthermore, these repeats, of which there are several hundred in the genome of the Medfly, can be used effectively for the determination of sequence polymorphisms, providing a convenient approach to obtain additional landmarks for the construction of genomic maps of this economically important insect.This paper is dedicated to the memory of our colleague and friend Dr. Jim Flach who took part in the initial phase of this work and died during the course of the investigation. 相似文献
5.
Petridis L Kneffel Z Kispéter Z Horváth P Sidó Z Pavlik G 《Acta physiologica Hungarica》2004,91(2):99-109
The purpose of this study was to examine the effects of different sport activities on cardiac adaptation. Echocardiographic data of 137 athletes and 21 non-athletes were measured and compared in two age groups 15-16 and 17-18 years of age. Athletes belonged into three groups according to their sports activity (endurance events, power athletes, ball game players). The observed variables were related to body size by indices in which the exponents of the numerator and the denominator were matched. Left ventricular hypertrophy was manifest in all athletic groups. Power athletes had the largest mean left ventricular wall thickness (LVWTd) in both age groups. In the older age group differences between the athletic groups were smaller, but the endurance and power athletes had significantly higher wall thickness. Left ventricular internal diameter (LVIDd) was the largest in the endurance athletes, while mean relative muscle mass (LVMM) was the largest in the power athletes. LVMM of the older endurance athletes was significantly larger. Muscular quotient (MQ) was the highest in the endurance athletes; in the 17-18-year group there was no inter-event difference. Bradycardia was most manifest in the endurance athletes and ball game players, power athletes had higher resting heart rates than non-athletic subjects. It can be inferred that endurance training induces firstly an enlargement of the left ventricle what is then followed by an increase of muscle mass. In the studied functional and regulatory parameters no difference was found between the athletic and non-athletic groups. 相似文献
6.
AMPK beta subunit targets metabolic stress sensing to glycogen 总被引:12,自引:0,他引:12
Polekhina G Gupta A Michell BJ van Denderen B Murthy S Feil SC Jennings IG Campbell DJ Witters LA Parker MW Kemp BE Stapleton D 《Current biology : CB》2003,13(10):867-871
AMP-activated protein kinase (AMPK) is a multisubstrate enzyme activated by increases in AMP during metabolic stress caused by exercise, hypoxia, lack of cell nutrients, as well as hormones, including adiponectin and leptin. Furthermore, metformin and rosiglitazone, frontline drugs used for the treatment of type II diabetes, activate AMPK. Mammalian AMPK is an alphabetagamma heterotrimer with multiple isoforms of each subunit comprising alpha1, alpha2, beta1, beta2, gamma1, gamma2, and gamma3, which have varying tissue and subcellular expression. Mutations in the AMPK gamma subunit cause glycogen storage disease in humans, but the molecular relationship between glycogen and the AMPK/Snf1p kinase subfamily has not been apparent. We show that the AMPK beta subunit contains a functional glycogen binding domain (beta-GBD) that is most closely related to isoamylase domains found in glycogen and starch branching enzymes. Mutation of key glycogen binding residues, predicted by molecular modeling, completely abolished beta-GBD binding to glycogen. AMPK binds to glycogen but retains full activity. Overexpressed AMPK beta1 localized to specific mammalian subcellular structures that corresponded with the expression pattern of glycogen phosphorylase. Glycogen binding provides an architectural link between AMPK and a major cellular energy store and juxtaposes AMPK to glycogen bound phosphatases. 相似文献
7.
We have conducted an evaluation of three of the most widely used commercial toxicity prediction programs, Toxicity Prediction by Komputer Assisted Technology (TOPKAT), Deductive Estimation of Risk from Existing Knowledge (DEREK) for Windows (DfW) and CASETOX. The three programs were evaluated for their ability to predict Ames test mutagenicity using 520 proprietary drug candidate (Test set 1) and 94 commercial (Test set 2) compounds. The study demonstrates that these three commercially available programs are useful, with limitations in their ability to predict mutagenicity over a wide range of chemical space, i.e. global predictivity. Individually, each of the programs performed at an acceptable level for overall accuracy, i.e. the ability to predict the correct outcome. However, analysis of the predictions indicates that the overall accuracy figure is heavily weighted by the ability of the programs to correctly predict non-mutagens, whereas none of the programs individually performed well in the prediction of novel mutagenic structures, i.e. Ames positive compounds. The performance of these programs' in predicting Ames positive mutagens appeared to be independent of the chemical utility of the compound, i.e. industrial, agricultural or pharmaceutical. The combination of program predictions provided some improvement in overall accuracy, sensitivity and specificity. 相似文献
8.
Manolas VM Pavlik G Bánhegyi A Faludi J Sidó Z Olexó Z 《Acta physiologica Hungarica》2001,88(3-4):259-270
The purpose of this cross-sectional investigation was to estimate the age at which specific traits of the "athlete's heart" first appear and how they evolve from the beginning of regular physical training until young adulthood in healthy active males. Male athletes (n=389) and non-athletes (n=55) aged between 9 and 20 years were examined by two-dimensionally guided M-mode and Doppler echocardiography. Intragroup differences were examined by t-tests for independent samples between age groups of two years each. Morphologic variables were related to body size by using ratio indices in which the power terms of numerator and denominator were matched. Relative left ventricular muscle mass (LVMM) was significantly larger in the athletic males at age of 11-12, and this significant difference was maintained with advancing age. Most of this increase of LVMM could be attributed to the increase in wall thickness that became significantly manifest first in the 13- to 14-year-old athletic subjects but was demonstrable in all the other groups. A significantly larger left ventricular internal diameter was only found in the age-group of 15-16. Fractional shortening percentage (FS%) did not show any change, while resting heart rate was decreased in our athletic groups. 相似文献
9.
Goutham Mylavarapu Shanmugam Murugappan Mihai Mihaescu Maninder Kalra Sid Khosla Ephraim Gutmark 《Journal of biomechanics》2009,42(10):1553-1559
An anatomically accurate human upper airway model was constructed from multiple magnetic resonance imaging axial scans. This model was used to conduct detailed Computational Fluid Dynamics (CFD) simulations during expiration, to investigate the fluid flow in the airway regions where obstruction could occur. An identical physical model of the same airway was built using stereo lithography. Pressure and velocity measurements were conducted in the physical model. Both simulations and experiments were performed at a peak expiratory flow rate of 200 L/min. Several different numerical approaches within the FLUENT commercial software framework were used in the simulations; unsteady Large Eddy Simulation (LES), steady Reynolds-Averaged Navier-Stokes (RANS) with two-equation turbulence models (i.e. k?ε, standard k?ω, and k?ω Shear Stress Transport (SST)) and with one-equation Spalart–Allmaras model. The CFD predictions of the average wall static pressures at different locations along the airway wall were favorably compared with the experimental data. Among all the approaches, standard k?ω turbulence model resulted in the best agreement with the static pressure measurements, with an average error of ~20% over all ports. The highest positive pressures were observed in the retroglossal regions below the epiglottis, while the lowest negative pressures were recorded in the retropalatal region. The latter is a result of the airflow acceleration in the narrow retropalatal region. The largest pressure drop was observed at the tip of the soft palate. This location has the smallest cross section of the airway. The good agreement between the computations and the experimental results suggest that CFD simulations can be used to accurately compute aerodynamic flow characteristics of the upper airway. 相似文献
10.
Masa-aki Higuchi Dan D. Topiol Bilal Ahmed Hokuto Morita Samuel Carbunaru Christopher W. Hess Dawn Bowers Herbert E. Ward Lisa R. Warren Meredith M. DeFranco Michelle S. Troche Shankar J. Kulkarni Erin Hastings Kelly D. Foote Michael S. Okun Daniel Martinez-Ramirez 《PloS one》2015,10(12)