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1.
The lack of comparative reviews of the efficacy of EMG frontalis biofeedback versus alternative procedures for reduction of muscle tension prompted the present meta-analytic treatment of literature previously concluded to be equivocal. Twenty studies comparing EMG frontalis biofeedback with other tension-reduction procedures produced a total of 68 separate effect sizes suitable for meta-analysis. Differences between clinical and normal samples were nonsignificant, and data analyses revealed that EMG frontalis biofeedback was significantly superior to control (p<.05) but that alternative forms of muscle relaxation, while effective, did not reach statistical significance.  相似文献   

2.
Summary Daytime numbers of pineal synaptic ribbons higher than reported in the pineal gland of any other mammalian species were observed in two diurnal rodents, the eastern chipmunk and Richardson's ground squirrel. The number of synaptic ribbons was lower during the daytime and higher at night in both of these species.  相似文献   

3.
Functionally active preparations of Na+,K+-ATPase isozymes from calf brain that contain catalytic subunits of three types (1, 2, and 3) were obtained using two approaches: a selective removal of contaminating proteins by the Jorgensen method and a selective solubilization of the enzyme with subsequent reconstitution of their membrane structure by the Esmann method. The ouabain inhibition constants were determined for the isozymes. The real isozyme composition of the Na+ pump from the grey matter containing glial cells and the brain stem containing neurons was determined. The plasma membranes of glial cells were shown to contain mainly Na+,K+-ATPase of the 11 type and minor amounts of isozymes of the 22(1) and the 31(2) type. The axolemma contains 21 and 31 isozymes. A carbohydrate analysis indicated that 11 enzyme preparations from the brain grey matter substantially differ from the renal enzymes of the same composition in the glycosylation of the 1 isoform. An enhanced sensitivity of the 3 catalytic subunit of Na+,K+-ATPase from neurons to endogenous proteolysis was found. A point of specific proteolysis in the amino acid sequence PNDNR492 Y493 was localized (residue numbering is that of the human 3 subunit). This sequence corresponds to one of the regions of the greatest variability in 1-, 2-, 3-, and 4-subunits, but at the same time, it is characteristic of the 3 isoforms of various species. The presence of the 3 isoform of tubulin (cytoskeletal protein) was found for the first time in the high-molecular-mass Na+,K+-ATPase 31 isozyme complex isolated from the axolemma of brain stem neurons, and its binding to the 3 catalytic subunit was shown.  相似文献   

4.
Using a cloning technique, we revealed the existence of three phototactically distinct types in Daphnia magna, viz. negatives, positives, and gipsies. The latter migrate continuously between a low and a high light intensity. The expression of this behaviour is genetically determined, although positives and negatives can reversibly switch into gipsies.It is proposed that two opposite genotypes exist, with the gipsy behaviour epigenetically induced. All juveniles behave more or less uniformly, irrespective of their origin. The phototactic responses develop rather late during ontogenesis.  相似文献   

5.
The relationship between finger pulse amplitude (PA) and frontalis EMG was studied first by looking at general physiological changes accompanying successful bidirectional PA control. Seven successful subjects were then asked to produce two patterns of PA and EMG (PAincEMGdec and PAdecEMGdec) while receiving both PA and frontalis EMG biofeedback. Results indicate subjects can easily produce the differentiation pattern of PAdecEMGdec but cannot produce the integration pattern of PAincEMGdec. These rather paradoxical results may indicate subjects were using an attentional rather than arousal strategy for controlling PA and have implications for the use of peripheral vasomotor training as a general relaxation technique.  相似文献   

6.
A spatially distributed mathematical model is developed to elucidate the effects of chemical diffusion and cell motility as well as cell growth, death, and substrate uptake on steady-state bacterial population growth in a finite, one-dimensional, nonmixed region. The situation considered is growth limited by a diffusing substrate from an adjacent phase not accessible to the bacteria. Chemotactic movement is not considered in this paper; we consider only randomwalk-type random motility behavior here. The following important general concepts are suggested by the results of our theoretical analysis: (a) The significance of random motility effects depends on the magnitude of the ratio/kL 2, where is the bacterial random motility coefficient,k is the growth rate constant, andL is the linear dimension of the confined growth region. (b) In steady-state growth in a confined region, the bacterial population size decreases as increases. (c) The effect of on population size can be great; in fact, sometimes relative population sizes of two species can be governed primarily by the relative values of rather than by the relative values ofk.  相似文献   

7.
Summary Two senscence-specific DNAs (sen-DNAs and ) were tested for their ability to drive autonomous replication in yeast and Podospora. The but not the sequence has autoreplicative (ARS) properties in yeast; the ARS sequences of are not included in the region common to all the sen-DNAs. Neither the nor the sequences can confer autoreplicative properties in Podospora. These sequences inserted into a hybrid vector carrying the suppressor tRNA, su4-1, do not change the mode of transformation of a suppressible leu-1-1 strain of Podospora: the transformation is by integration whether or not the plasmid carries a sen-DNA sequence. The su4-1 gene integrates at its homologous site in a minority of cases. It is possible to reisolate free plasmids at a low frequency from some transformants. The presence of a sen-DNA on the transforming vector has no effect upon the longevity of the transformants.  相似文献   

8.
The Arabidopsis G subunit, GP1, was expressedwithin Escherichia coli by co-transformation with the expressionvector and the dnaY gene which encodes tRNAArg AGA/AGG. Isolation of the recombinant GP1 in a highly pureform could be achieved by a combination of anion exchange and dyeaffinity chromatography or by a single step affinity procedure viachromatography on 4-amino-anilido-GTP agarose. The recombinant proteinyielded by both procedures was highly active and bound GTPS withan apparent Kd in the nM range. GTPS binding wasstimulated two-fold in the presence of Zn2+ compared with that inthe presence of Mg2+, Mn2+ or Ca2+.Abbreviations: 4aaGTP, 4-amino-anilido-GTP; GTPS,guanosine- 5-(3-O-thiotriphosphate), PMSF,phenylmethylsulphonyl fluoride; PVDF, polvinylidene fluoride;rGP1, recombinant GP1  相似文献   

9.
From tibialis anterior to Tai Chi: biofeedback and beyond   总被引:1,自引:0,他引:1  
This keynote presentation highlights events that have contributed to scientific explorations of one research clinician. Steve Wolf traces his scientific roots to early studies in single motor unit control under the guidance of his primary mentor, John Basmajian, MD. This work led to subsequent studies on the role of EMG feedback in predicting successful outcomes in upper extremity use and in ambulatory capabilities among patients with chronic stroke. These findings are contrasted to further efforts to condition entire reflexes rather than individual muscles through use of operant-conditioning paradigms. The findings from applications of EMG biofeedback to stroke patients became the basis for minimal motor criteria in the treatment of the impaired upper extremities of patients with chronic stroke, using forced use or constraint-induced movement therapy. Last, investigations into center of pressure feedback using computerized balance machines resulted in a series of experiments that ultimately led to the finding that Tai Chi as an exercise form for older adults can have a substantially favorable effect in delaying the onset of fall events.  相似文献   

10.
Successful treatment of torticollis with electromyographic (EMG) biofeedback has been reported in a number of single case and single group studies. The present investigation represents the first controlled outcome study. Twelve torticollis patients were randomly assigned to EMG biofeedback or relaxation training and graded neck exercises (RGP). The procedure involved three sessions of baseline assessment, 15 sessions of EMG BF or RGP, 6 sessions of EMG BF or RGP plus home-management, 6 sessions of home-management alone, and follow-up 3 months after the end of treatment. A variety of outcome measures were used including physiological (EMG from the two sternocleidomastoid muscles, skin conductance level), behavioral (angle of head deviation, range of movement of the head), and self-report (depression, functional disability, body concept), therapist and significant other reports and independent observer assessment of videos. In both groups, neck muscle activity was reduced from pre- to posttreatment. This reduction was greater in the EMG biofeedback group. There was evidence of feedback-specific neck muscle relaxation in the EMG biofeedback group. Therefore, the outcome was not due to nonspecific factors and could be attributed to feedback-specific effects. Changes in skin conductance level showed that neck muscle relaxation was not simply mediated by a general reduction of arousal. Significant improvements of extent of head deviation, and range of movement of the head, as well as reductions of depression were present, which were not different in the two groups. At the end of treatment, no patient was asymptomatic. Any therapeutic benefit was generally maintained at follow-up. The results and the procedural simplicity of RGP make the issue of cost-efficacy of EMG biofeedback a pertinent one. Further controlled outcome studies of EMG biofeedback treatment of torticollis with larger samples are required.This work was funded by grants from the Medical Research Council and the Dystonia Society.  相似文献   

11.
Summary The high-resolution structure of a dimeric conformer of gramicidin A, a 15-residue polypeptide, has been determined in the mixed-solvent system of benzene and ethanol by 2D NMR techniques. NOEs, coupling constants and hydrogen-bond information were used to generate 744 experimental constraints for the dimer. Stereoassignment of most -methylene groups was achieved by analysis of 3J, d(i,i), dN(i,i) and dN(i+1,i) distances, and consideration of the initial backbone structure determinations. Stereoassignment of several leucine methyl groups was accomplished via a distance geometry/simulated annealing routine, used for structure determination and refinement. The relatively static backbone structure was determined first and held rigid while side-chain conformations were calculated. This procedure is evaluated versus standard NMR structure determination protocols. The backbone is an antiparallel intertwined double helix, with 5.6–5.7 residues per turn, a total dimer length of 36–37 Å, and a pore width of 2.5–3.0 Å (van der Waals to van der Waals). The structure and dynamics of the side chains are discussed in depth, with careful attention for both the convergence of structures and the residual constraint violations per residue. Side-chain positions impart substantial amphipathic character to the helix, which could influence the conformational change that takes place upon membrane insertion of this channel-forming polypeptide.To whom correspondence should be addressed.  相似文献   

12.
13.
There is basis for concern that applied psychophysiology, if not the field of biofeedback, is being coopted by, and merged into, a reborn inner model, with the return of cognition to preeminence in the psych and neuro disciplines. Despite currently fashionable views that such mentalistic inventions and neuro/psychological developments somehow illuminate behavior or offer simpler accounts of behavioral facts, there is little or no evidence that any such construction has ever told us anything new about behavior.Preparation of this article was supported in part by the following PHHS Grants: NHLBI HL 34034, NIDA DA 03476, NIDA DA 04130, NIDA DA 02490, NIDA DA 04133, NIDA DA 01147, NIDA DA 04731, and NIDA contract 271-86-8113.  相似文献   

14.
Residual toxicities of registered and selected experimental pesticides used on citrus against Agistemus industani Gonzalez (Acari: Stigmaeidae) were compared. Pesticides considered highly toxic to A. industani were: abamectin 0.15 EC at 731ml/ha+FC 435-66 petroleum oil at 46.8l/ha, pyridaben 75WP at 469g/ha, ethion 4EC at 7.01l/ha+FC 435-66 petroleum oil at 46.8l/ha, propargite 6.55 EC at 3.51l/ha, chlorfenapyr 2SC at 1.46l/ha applied alone or in combination with FC 435-66 petroleum oil at 46.8l/ha, sulphur 80DF at 16.81kg/ha, dicofol 4EC at 7.01l/ha, fenbutatin oxide 50WP at 2.24kg/ha, benomyl 50WP at 2.24kg/ha, benomyl 50WP at 1.68kg/ha+ferbam 76 GF at 5.60kg/ha, ferbam 76GF at 11.21kg/ha, neem oil 90EC at 46.8l/ha, and copper hydroxide DF (40% metallic copper) at 4.48kg metallic copper/ha+FC 435-66 petroleum oil at 46.8l/ha. Pesticides that were moderately to slightly toxic included: copper sulphate 98% at 4.48kg metallic copper/ha+FC 435-66 petroleum oil at 46.8l/ha, fenbuconazole 2F at 280ml/ha+FC 435-66 petroleum oil at 46.8l/ha, FC 435-66 petroleum oil applied alone at 46.8l/ha or 23.4l/ha, and diflubenzuron 25WP at 1.40kg/ha. Pesticides that were non-toxic included: fenbuconazole 2F at 585ml/ha, malathion 57EC at 5.85l/ha, FC 435-66 petroleum oil at 46.8l/ha, carbaryl 80S at 3.36kg/ha, chlorpyrifos 4EC at 4.68l/ha, and formetanate 92SP at 1.12kg/ha. Understanding the toxic effects of field weathered pesticides against key predacious mite species is important for effective IPM. The results of this study provide a comparison of direct and indirect toxic effects of various pesticides to A. industani under field conditions.  相似文献   

15.
Six male volunteers assumed either relaxed or unrelaxed postures, as defined by a Behavioral Relaxation Scale, in seven areas of the body. Electromyographic (EMG) levels in the muscle groups associated with each area were determined for both categories of postures. In all instances, the relaxed postures produced significantly lower EMG levels than the unrelaxed postures. This indicates that the Behavioral Relaxation Scale is a valid behavioral measure of relaxation. Also, it supports other studies which have shown that direct training in emitting relaxed postures is an effective means of achieving relaxation.This study was conducted in partial fulfillment of the M.A. degree by Jerry P. Maurer. Appreciation is expressed to Tz-Yi Jiang, Dr. Robert Lehr, and Jim Rice for their assistance.  相似文献   

16.
Summary The water permeability of phospholipid vesicles 0.5 to 10 in diameter bounded by one or by several lipid bilayers was measured by following the change in turbidity of a suspension after mixing in a stopped flow apparatus. A semi-empirical formulation for evaluating volume changes of vesicles with a broad size range by measurement of turbidity is developed. The rate of flow is analyzed in terms of reaction rate theory. The water permeability coefficients for phosphatidylcholine vesicles were approximately 44 /sec at 25°C and 70 /sec at 37°C. The activation energy for water transport was 8.25 kcal/mole. The results were consistent with the view that water permeates by dissolution and diffusion in the membrane.  相似文献   

17.
This study investigated the effects of performance feedback and EMG biofeedback on perceptions of the self (i.e., self-esteem, self-control, self-efficacy, and locus of control) as well as on a self-control behavior (study skills) the subjects performed outside the laboratory. Forty-seven college students were randomly assigned to one of four groups in a 2(high and low success feedback) × 2(true and false EMG biofeedback) factorial experiment with repeated measures. All of the participants received four sessions of EMG biofeedback, and later they were asked to self-monitor their study habits for 2 weeks. Results showed that the self-esteem measure and perceptions of study skills improvement were differentially affected by success feedback but unrelated to the true or false EMG manipulation. Shifts toward an internal locus of control and perceptions of improved self-control were also noted, but they were independent of the subjects' group membership. Implication of the results are briefly discussed.  相似文献   

18.
The carbohydrate-binding specificity ofPseudomonas aeruginosa lectin I (PA-I) in iodinated or biotinylated form was studied. A large number of glycosphingolipids, as well as some glycoproteins and neoglycoproteins were used as ligands. Also, inhibition by free saccharides of PA-I binding to glycosphingolipids was tested. It was found that the lectin binds most strongly to terminal and nonsubstituted Gal3Gal- or Gal4Gal-structures.Abbreviations PA-I Pseudomonas aeruginosa lectin I - Cer ceramide - lactosylceramide Gal4GlcCer - iso globotriaosylcerami Gal3Gal4GlcCer - globotriaosylceramide Gal4Gal4GlcCer - globoside or globotetraosylceramide GalNAc3Gal4Gal4GlcCer - Forssman glycolipid GalNAc3GalNAc3Gal4Gal4GlcCer - P1 glycolipid Gal4Gal4GlcNAc3Gal4GlcCer - lactoneotetraosylceramide Gal4GlcNAc3Gal4GlcCer - B5 glycolipid Gal3Gal4GlcNAc3Gal4GlcCer - gangliotetraosylceramide Gal3GalNAc4Gal4GlcCer - GM1 Gal3GalNAc4(NeuAc3)Gal4GlcCer - RBC red blood cells - BSA bovine serum albumin - PBS phosphate-buffered saline - SDS sodium dodecyl sulfate - TLC thin-layer chromatography - HPLC high pressure liquid chromatography - MS mass spectrometry - FAB fast-atom bombardment - EI electron impact  相似文献   

19.
Daniel J. Cosgrove 《Planta》1987,171(2):266-278
This study was carried out to develop improved methods for measuring in-vivo stress relaxation of growing tissues and to compare relaxation in the stems of four different species. When water uptake by growing tissue is prevented, in-vivo stress relaxation occurs because continued wall loosening reduces wall stress and cell turgor pressure. With this procedure one may measure the yield threshold for growth (Y), the turgor pressure in excess of the yield threshold (P-Y), and the physiological wall extensibility (). Three relaxation techniques proved useful: turgor-relaxation, balance-pressure and pressure-block. In the turgor-relaxation method, water is withheld from growing tissue and the reduction in turgor is measured directly with the pressure probe. This technique give absolute values for P and Y, but requires tissue excision. In the balance-pressure technique, the excised growing region is sealed in a pressure chamber, and the subsequent reduction in water potential is measured as the applied pressure needed to return xylem sap to the cut surface. This method is simple, but only measures (P-Y) not the individual values of P and Y. In the pressure-block technique, the growing tissue is sealed into a pressure chamber, growth is monitored continuously, and just sufficient pressure is applied to the chamber to block growth. The method gives high-resolution kinetics of relaxation and does not require tissue excision, but only measures (P-Y).The three methods gave similar results when applied to the growing stems of pea (Pisum sativum L.), cucumber (Cucumis sativus L.), soybean (Glycine max (L.) Merr.) and zucchini (Curcubita pepo L.) seedlings. Values for (P-Y) averaged between 1.4 and 2.7 bar, depending on species. Yield thresholds averaged between 1.3 and 3.0 bar. Compared with the other methods, relaxation by pressure-block was faster and exhibited dynamic changes in wall-yielding properties. The two pressure-chamber methods were also used to measure the internal water-potential gradient (between the xylem and the epidermis) which drives water uptake for growth. For the four species it was small, between 0.3 and 0.6 bar, and so did not limit growth substantially.Symbols L tissue hydraulic conductance - P cell turgor pressure - Y wall yield threshold - volumetric elastic modulus - physiological wall extensibility  相似文献   

20.
The main carotenoid of Flavobacterium strain R1560 has been identified as (3R,3R)-zeaxanthin. Also present were small amounts of 15-cis-phytoene, phytofluene, -carotene (7,8,7,8-tetrahydro-, -carotene plus 7,8,11,12-tetrahydro-, -carotene), neurosporene, lycopene, -zeacarotene, -carotene, -carotene, -cryptoxanthin, rubixanthin, 3-hydroxy--zeacarotene and several apo-carotenals. Zeaxanthin production was inhibited by nicotine (10 mM), and lycopene and rubixanthin accumulated. The biosynthesis of zeaxanthin is discussed in terms of pathways and also of half-molecule reaction sequences. The presence of zeaxanthin may be a characteristic of a group of Flavobacterium species, and may thus be useful in the taxonomic classification of these organisms.  相似文献   

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