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91.
Growth and development of biofeedback: A bibliographic update 总被引:1,自引:0,他引:1
Computerized literature searching techniques were used to examine publication patterns in the worldwide biofeedback literature. Searches were completed in the United States and in Japan for the years 1985 through 1987. The results were used to update the results of an earlier study (Hatch & Riley, 1985) that covered the years from 1964 through 1984. Publication growth curves were generated for several media, including scientific journal articles, books, doctoral dissertations, and popular magazine articles. Although publication of information about biofeedback remains active worldwide, there has been a declining trend in effect for the past several years. The American database grossly underestimated the number of Japanese biofeedback articles, and it is likely that the literatures of other countries outside of North America were similarly underestimated. Possible explanations for the various trends noted are discussed.These results were presented in part at the Twentieth Annual Meeting of the Association for Applied Psychophysiology and Biofeedback. We gratefully acknowledge the assistance of Margaret Cyr-Provost in preparing the data for analysis. 相似文献
92.
M. Couturier F. Lemonnier M. Conti M. Feneant-Thibault A. Lemonnier 《In vitro cellular & developmental biology. Plant》1990,26(1):29-32
Summary 2-Deoxy-d-glucose (2-DOG) uptake was tested in human fibroblast cultures in the presence and absence of vitamin E. Addition of 10 μg/ml
vitamin E to the culture medium significantly reduced this uptake for 2-DOG concentrations of 0.005, to 10 mmol/liter (P≤0.01). The decrease of 2-DOG uptake was inversely proportional to the rise in 2-DOG concentration (P≤0.01). The presence of vitamin E reduced by 71% the average cellular level of lipid peroxides (expressed as thiobarbituric
acid reactive substances) and caused a small but significant decrease in the cholesterol concentration (P≤0.01). These last results might explain the decrease in 2-DOG uptake observed in the presence of vitamin E. 相似文献
93.
S. Meintjes 《Hydrobiologia》1996,325(3):213-218
Reproductive traits of Triops granarius females were examined. Fertilization by males was a prerequisite for oviposition. Clutch size ranged from 1 to 154, and clutch frequency (per 24 hours) from 1 to 9. Clutch size generally increased with increasing body size and increasing age. Total reproductive output was dependent upon life span, and estimated at around 200 eggs for a life span of 25 days. Clutch data indicate that T. granarius may have r-selected traits. 相似文献
94.
Airborne particles and ammonia were monitored in horse stalls managed under four conditions. Two ventilation rates, high (27 air changes per h) and low (5 air changes per h) and two bedding types, paper and straw, were employed. At both ventilation rates, the number of airborne particles generated while the stalls were mucked out was higher with straw than with paper. Particles were more efficiently cleared at the higher ventilation rate in both the straw and paper stalls. Ammonia measurements reflected an accumulation over time. In the stalls with low ventilation, ammonia levels were significantly higher than in those stalls with high ventilation regardless of bedding type. Management decisions and their relationships to respiratory disorders are discussed. 相似文献
95.
Ouriel Faktor Jan M. Kooter Richard A. Dixon Chris J. Lamb 《Plant molecular biology》1996,32(5):849-859
Expression of chalcone synthase (CHS), the first enzyme in the flavonoid branch of the phenylpropanoid biosynthetic pathway in plants, is induced by developmental cues and environmental stimuli. We used plant transformation technology to delineate the functional structure of the French bean CHS15 gene promoter during plant development. In the absence of an efficient transformation procedure for bean, Nicotiana tabacum was used as the model plant. CHS15 promoter activity, evaluated by measurements of -d-glucuronidase (GUS) activity, revealed a tissue-specific pattern of expression similar to that reported for CHS genes in bean. GUS activity was observed in flowers and root tips. Floral expression was confined to the pigmented part of petals and was induced in a transient fashion. Fine mapping of promoter cis-elements was accomplished using a set of promoter mutants generated by unidirectional deletions or by site-directed mutagenesis. Maximal floral and root-specific expression was found to require sequence elements located on both sides of the TATA-box. Two adjacent sequence motifs, the G-box (CACGTG) and H-box (CCTACC(N)7CT) located near the TATA-box, were both essential for floral expression, and were also found to be important for root-specific expression. The CHS15 promoter is regulated by a complex interplay between different cis-elements and their cognate factors. The conservation of both the G-box and H-box in different CHS promoters emphasizes their importance as regulatory motifs. 相似文献
96.
Anthers of diploid genotypes of Solanum tuberosum capable of androgenesis were cultured on different media to examine the effect on induction of pollen embryogenesis of 2,4-d and lactose. Anthers cultured in callogenic medium with 2,4-d and sucrose produced pollen derived embryoids only exceptionally. When sucrose was replaced by lactose the frequency of embryogenesis was as high or higher than in embryogenic auxin-free medium. Substitution of lactose for sucrose in the embryogenic medium had no effect. Supplementing the embryogenic medium with 2,4-d strongly reduced the frequency of pollen embryoids in the presence of sucrose but not with lactose.Abbreviations 2,4-d
2,4-dichlorophenoxyacetic acid 相似文献
97.
Sub Sunoo Katsumi Asano Fumiyuki Mitsumori 《European journal of applied physiology and occupational physiology》1996,74(4):305-310
We measured ATP, phosphocreatine (PCr), inorganic phosphate (Pi), and the intracellular pH in rat hindlimb muscles during submaximal isometric exercise with various O2 deliveries using31P nuclear magnetic resonance spectroscopy (31P NMR) to evaluate changes in energy metabolism in relation to O2 availability. Delivery of O2 to muscles was altered by controlling the fractional concentration of inspired oxygen (F
IO2) at 0.50, 0.28, 0.21, 0.11 and 0.08 with monitoring partial pressure of oxygen and carbon dioxide, and bicarbonate at the femoral artery. The steady-state ratio of PCr : (PCr + Pi) during exercise decreased as a function ofF
IO2 even at 0.21. Significant acidification of the intracellular pH during exercise occurred at 0.08F
IO2. Change in the PCr : (PCr + Pi) ratio demonstrated that the oxidative capacity, i.e. the maximal rate of the oxidative phosphorylation reaction, in muscle was not limited by O2 delivery at 0.50F
IO2, but was significantly limited at 0.21F
IO2 or below. Change in the intracellular pH at 0.08F
IO2 could be interpreted as an increase in lactate, suggesting activation of glycolysis. Correlation between the PCr : (PCr + Pi) ratio and the intracellular pH revealed the existence of a critical PCr : (PCr + Pi) ratio and pH for glycolysis activation at around 0.4 and 6.7, respectively. 相似文献
98.
99.
Three routes were investigated for the conversion of d-glucose into the title compound. In the first approach, reduction of the 5,6-thürane ring of 5,6-dideoxy-5,6-epithio-1,2-O-isopropylidene α-d-glucofuranose (17) as well as that of its 3-O-allyl derivative (13) with lithium aluminium hydride was investigated; 17 afforded the corresponding 6-deoxy derivative besides di-, tri-, and poly-mers, whereas only polymers were formed from 13. In the second approach, the oxirane ring of was reduced by sodium borohydride and the resulting 6-deoxy derivative was converted into the 5-thiobenzoate; the corresponding hex-4-enofuranose was formed as a byproduct. In the third approach partial mesylation of methyl 5-thio-α-d-glucopyranoside was attempted, but the 6-mesylate 27 could be isolated only in modest yield (28%) together with rearranged 2,5-thioanhydromannofuranoside derivatives. The mechanism of this rearrangement is discussed in detail. The 6-mesylate 27 was converted via the 6-iodo derivative into the title compound. 相似文献
100.
Tenshuk A. Kadima Susan E. Jensen Michael A. Pickard 《Journal of industrial microbiology & biotechnology》1995,14(1):35-40
Summary -(l--Aminoadipyl)-l-cysteinyl-d-valine (ACV)-synthetase fromStreptomyces clavuligerus was studied under conditions that enabled the reuse of the enzyme. Coupling of ACV-synthetase to DEAE-Trisacryl and aminopropyl-glass resulted in an immobilized enzyme product of little or no catalytic activity. However, an enzyme reactor was designed by physical confinement of partially-purified ACV-synthetase in an ultrafiltration cell. This system was stimulated by phosphoenolpyruvate at lower concentrations of ATP, an effect not observed with purified enzyme. Up to 30% conversion of the limiting substrate, cysteine, to ACV occurred under semi-continuous conditions. Reaction products were investigated as potential inhibitors: AMP was the most inhibitory, but only when used at concentrations in excess of those produced in reaction mixtures. Under a nitrogen atmosphere, both product and enzyme stabilities were greatly improved and the enzyme retained 45–46% of its initial activity after five uses at room temperature during a 24-h period. Extrapolations based on these data suggest that 1.3 g partially purified enzyme (0.13 U g–1) would be capable of producing 411 mg of ACV in a 1-L reaction mixture in this period. 相似文献