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排序方式: 共有231条查询结果,搜索用时 15 毫秒
1.
The Fis protein: it''s not just for DNA inversion anymore 总被引:36,自引:0,他引:36
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Candida Finkel Abrahamson 《Applied psychophysiology and biofeedback》1987,12(2):121-125
This notes pursues the theme introduced in the first Notes and Observations publication: the effectiveness of biofeedback in treatment of the elderly. Current clinical results in progress are reported for a 76-year-old female hypertensive whose blood pressure has to date been lowered from 190/90 to 160/82 by means of thermal biofeedback in conjunction with progressive relaxation. These results are contrasted with reported failures in the headache study of elderly patients (Blanchard, Andrasik, Evans, & Hillhouse 1985). Results of this study are reinterpreted in terms of biofeedback modality rather than age of subjects. 相似文献
4.
D L Finkel 《Journal of theoretical biology》1992,154(3):285-302
The human T-lymphotropic retroviruses HTLV-I and HIV-1/-2 share a complementary patchwork homology in which the RRE regions of HIV-1 and -2 cover 78.1% of a 169 nucleotide (nt) region (PX1,2) positioned precisely between open reading frames PX I and PX II of ATLV (HTLV-I). The sequence character of the PX1,2 region is shown to be influenced by a primordial expansion, CTC2T, originating several hundred nucleotides upstream. A second primordial expansion, AGCU(U/C), is identified and shown to represent 52.1% of the HIV-1 RRE region. It is argued that prior to the present AIDS pandemic the efficiency of the rev receptor was enhanced by an ancestral recombination event. 相似文献
5.
A 106 kD protein was isolated from skeletal sarcoplasmic reticulum (SR) vesicles and shown to have the properties of SR Ca2+ release channels, including blockade by 5 nM ryanodine. In view of extensive reports that the ryanodine-receptor complex consists of four 565 kD junctional feet proteins (JFPs) and is the 'physiological' Ca2+ release channel, we prepared ryanodine-affinity columns to isolate its receptor site(s). Conditions known to maximize the association and dissociation of ryanodine to SR proteins were respectively used to link, then elute, the receptor(s) from ryanodine-affinity columns. The method purified a protein at about 100 kD from both rabbit skeletal and canine cardiac SR vesicles. The skeletal and cardiac proteins isolated by ryanodine-affinity chromatography were identified as the low molecular weight Ca2+ release channel through their antigenic reaction with an anti-106 kD monoclonal antibody. Upon reconstitution in planar bilayers, both skeletal and cardiac proteins revealed the presence of functional SR Ca2+ release channels. Surprisingly, ryanodine-affinity columns did not retain JFPs but purified 106 kD Ca2+ release channels which are a minor component (0.1-0.3%) of SR proteins. 相似文献
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Myriam V. Thoma Roberto La Marca Rebecca Br?nnimann Linda Finkel Ulrike Ehlert Urs M. Nater 《PloS one》2013,8(8)
Background
Music listening has been suggested to beneficially impact health via stress-reducing effects. However, the existing literature presents itself with a limited number of investigations and with discrepancies in reported findings that may result from methodological shortcomings (e.g. small sample size, no valid stressor). It was the aim of the current study to address this gap in knowledge and overcome previous shortcomings by thoroughly examining music effects across endocrine, autonomic, cognitive, and emotional domains of the human stress response.Methods
Sixty healthy female volunteers (mean age = 25 years) were exposed to a standardized psychosocial stress test after having been randomly assigned to one of three different conditions prior to the stress test: 1) relaxing music (‘Miserere’, Allegri) (RM), 2) sound of rippling water (SW), and 3) rest without acoustic stimulation (R). Salivary cortisol and salivary alpha-amylase (sAA), heart rate (HR), respiratory sinus arrhythmia (RSA), subjective stress perception and anxiety were repeatedly assessed in all subjects. We hypothesized that listening to RM prior to the stress test, compared to SW or R would result in a decreased stress response across all measured parameters.Results
The three conditions significantly differed regarding cortisol response (p = 0.025) to the stressor, with highest concentrations in the RM and lowest in the SW condition. After the stressor, sAA (p=0.026) baseline values were reached considerably faster in the RM group than in the R group. HR and psychological measures did not significantly differ between groups.Conclusion
Our findings indicate that music listening impacted the psychobiological stress system. Listening to music prior to a standardized stressor predominantly affected the autonomic nervous system (in terms of a faster recovery), and to a lesser degree the endocrine and psychological stress response. These findings may help better understanding the beneficial effects of music on the human body. 相似文献8.
Increased internal and external bacterial load during Drosophila aging without life-span trade-off 总被引:3,自引:0,他引:3
The role of microbial load during aging of the adult fruit fly Drosophila melanogaster is incompletely understood. Here we show dramatic increases in aerobic and anaerobic bacterial load during aging, both inside the body and on the surface. Scanning electron microscopy and cell staining analyses of the surface of aged flies detected structures resembling abundant small bacteria and bacterial biofilms. Bacteria cultured from laboratory flies included aerobic species Acetobacter aceti, Acetobacter tropicalis, and Acetobacter pasteurianus and anaerobic species Lactobacillus plantarum and Lactobacillus sp. MR-2; Lactobacillus homohiochii, Lactobacillus fructivorans, and Lactobacillus brevis were identified by DNA sequencing. Reducing bacterial load and antimicrobial peptide gene expression by axenic culture or antibiotics had no effect on life span. We conclude that Drosophila can tolerate a significant bacterial load and mount a large innate immune response without a detectable trade-off with life span; furthermore, microbes do not seem to limit life span under optimized laboratory conditions. 相似文献
9.
Metabolism and mitochondrial activity are thought to be important determinants of life span. A new study in this issue of Cell Metabolism (Bonawitz et al., 2007) suggests that the TOR pathway controls mitochondrial respiration in yeast and that the harder mitochondria work, the longer yeast live. 相似文献
10.
The macromolecular composition of macroalgae influences nutrient flow and food quality in aquatic ecosystems and the value of macroalgae species for human consumption, aquaculture, biofuels, and other applications. We used literature data (125 publications, 1,117 observations) and a hierarchal Bayesian statistical model to estimate the average macromolecular composition, protein, lipid, and carbohydrate of macroalgae as a whole and at the phylum level. Our focus was on marine, noncalcified macroalgae sampled from wild‐grown populations in the field. We found that the median macromolecular composition is 9.98% protein, 2.7% lipid, 48.5% carbohydrate, and 31.8% ash as percent dry weight. We compared the median macromolecular content of macroalgae to microalgae and herbaceous plants and test for differences in macromolecular content across macroalgal phyla. Macroalgae were much more enriched in carbohydrate and minerals than the microalgae and lower in protein and lipid than many herbaceous plants. Rhodophyte macroalgae have significantly less lipid and more protein and the Ochrophyte macroalgae have significantly less protein than the average. 相似文献