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91.
The presence or absence of light during flotation restricted environmental stimulation: Effects on plasma cortisol,blood pressure,and mood 总被引:1,自引:0,他引:1
John W. Turner Jr. Thomas Fine Gina Ewy Peter Sershon Thomas Freundlich 《Applied psychophysiology and biofeedback》1989,14(4):291-300
This study examined the effect of light on relaxation associated with flotation restricted environmental stimulation therapy (REST), as measured by plasma cortisol, mean arterial pressure, and psychometric parameters. Twenty-one subjects were paired by baseline cortisol levels into two groups: one experiencing flotation REST in the presence of light (REST-L) and one experiencing flotation REST in the absence of light (REST-D). Subjects were 15 male and 6 female students aged 22–28 in normal health who had not experienced REST. Repeated flotation REST (8 sessions) either with light or without light was associated with a decrease in plasma cortisol and a decrease in mean arterial pressure, with no differences in effectiveness between groups. The psychometric assessment of mood, using the POMS scale, before and after sessions 1 and 8 revealed mood state improvement in both REST-L and REST-D groups. These data suggest that the presence of light did not compromise the flotation REST experience, as evidenced by the lack of difference between REST-L and REST-D groups. 相似文献
92.
Frequency of infection by Cryptosporidium sp. in 1,039 faecal smears stained by Ziehl-Neelsen, obtained from undernourished patients of a Nutritional Recovery Center and an ambulatory undernourished center from the Fifth Region, Chile, were studied. All underwent a coproparasitological examination by the modified Telemann method. Thirty eight (3.7%) patients infected by the parasite were detected, with an overall frequency of 8.5% among patients of the Nutritional Recovery Center and 1.9% among the ambulatory patients; this difference was statistically significant. The highest percentage of positive results were detected among the younger milk feeding infants. Also the percentage of difference among these and the older milk feeding infants (3.7%) was statistically significant. Association of Cryptosporidium sp. and Giardia lamblia was observed in 6 ambulatory patients (2.3%). 相似文献
93.
Carlos A. Leguizamón 《Bulletin of mathematical biology》1976,38(5):547-563
In order to recognize the realizability of inputs with different physical natures through a component, Yoneda's Lemma is applied.
The major utility of this Lemma is when the components produce only energy. From this, it is assumed that a new material input
must exist which was not recognized in the original developments in biological systems representation. Moreover, simple transfers
of energy, between objects, components, and among both objects and components are developed under the generic name; energetical
evolution. Thus, energetical evolution appears as anew element in the abstract representation of biological systems. These new concepts are incorporated into a new abstract diagram and
a newM
β category.
This paper was made possible by a Fellowship from the Consejo Nacional de Investigaciones Científicas y Técnicas of the República
Argentina. 相似文献
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Localized P1 mutagenesis was used to screen for conditionally lethal mutations in ribosomal protein genes. One such mutation, 2859mis, has been mapped inside the ribosomal protein gene cluster at 72 minutes on the Escherichia coli chromosome and cotransduces at 98% with rpsE (S5). The 2869mis mutation leads to thermosensitivity and impaired assembly in vivo of 50 S ribosomal particles at 42 °C. The strain carrying the mutation has an altered L24 ribosomal protein which at 42 °C shows weaker affinity for 23 S RNA than the wild-type protein. The mutational alteration involves a replacement of glycine by aspartic acid in protein L24 from the mutant. We conclude therefore that the 2859mis mutation affects the structural gene for protein L24 (rplX). 相似文献
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Mark T Uhlik Amy N Abell Bruce D Cuevas Kazuhiro Nakamura Gary L Johnson 《Biochimie et biologie cellulaire》2004,82(6):658-663
Mitogen-activated protein kinase (MAPK) pathways are activated by a plethora of stimuli. The literature is filled with papers describing the activation of different MAPKs by almost any stimulus or insult imaginable to cells. In this review, we use signal transduction wiring diagrams to illustrate putative upstream regulators for the MAPK kinase kinases, MEKK1, 2, and 3. Targeted gene disruption of MEKK1, 2, or 3 defined phenotypes for each MEKK associated with loss of specific MAPK regulation. Genetic analysis of MEKK function clearly defines specific components of the wiring diagram that require MEKK1, 2, or 3 for physiological responses. We propose that signal transduction network wiring diagrams are valuable tools for hypothesis building and filtering physiologically relevant phenotypic responses from less connected protein relations in the regulation of MAPK pathways. 相似文献
100.
The fraction of free fatty acids (FFA) is present in skeletal muscles. However, there is almost no data regarding regulation in the content of this intramuscular lipid pool. We took advantage of the isolated muscle preparation to examine whether: a) increasing exogenous concentration of FFA (500microM or 700microM, 30min) b) insulin (10.00 I.U./L, 30min), c) adrenalin (4.4 nM, 30 min), or d) contractions (200ms, tetani, 1Hz, 30min), affect the FFA content inside myocytes. Incubation of soleus (S) and extensor digitorum longus (EDL) with increasing concentrations of exogenous FFA (from 500microM to 700microM) resulted in an increase in the total FFA fraction in both muscles studied (by 280.2% and 259.1%, respectively). In contracting muscles FFA pool was significantly reduced both in S (by 73.1%) and in EDL (by 31.1%). Neither stimulation by adrenalin nor insulin affected the total content of FFA fraction in the muscles examined. We conclude that a) increased availability of exogenous FFA at the sarcolemma level results in an increase in the size of intramuscular FFA fraction b) the intracellular FFA fraction is utilized by contracting muscles with regard to the fiber composition and to a greater extent in more oxidative muscles, c) FFA fraction remains stable upon stimulation by insulin or adrenalin. 相似文献