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排序方式: 共有135条查询结果,搜索用时 15 毫秒
1.
Carles Grau Romuald Ginhoux Alejandro Riera Thanh Lam Nguyen Hubert Chauvat Michel Berg Julià L. Amengual Alvaro Pascual-Leone Giulio Ruffini 《PloS one》2014,9(8)
Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues. 相似文献
2.
Clinical and biochemical studies in three patients with severe early infantile Cockayne syndrome 总被引:2,自引:0,他引:2
Jaak Jacken Helmut Klocker Helga Schwaiger Romuald Bellmann Monica Hirsch-Kauffmann Manfred Schweiger 《Human genetics》1989,83(4):339-346
Summary We present clinical and biochemical data from three patients with severe Cockayne syndrome (CS) of very early onset. Unlike in classic CS, signs became evident in the first weeks of life and led to unusually early death. Fibroblasts from two of the patients showed a complete defect of the repair of UV-induced thymine dimer lesions. They were unable to remove thymine dimer lesions from their DNA, had a severe reduction of the RNA synthesis rates after UV irradiation, and showed no reactivation of an UV-inactivated indicator gene and no DNA recondensation after UV irradiation. DNA repair investigated in these two fibroblast cell strains resembled that of xeroderma pigmentosum cells of complementation group A. In contrast, fibroblasts from the third patient showed the same in vitro repair characteristics as classic CS cells. 相似文献
3.
Questions relating to the antiquity of domestic cattle in the Sahara are among the most controversial in North African prehistory. It is generally believed that cattle were first domesticated in southwest Asia, particularly Anatolia, or in southeast Europe, where their remains have been found in several sites dated between 9,000 and 8,000 years ago.1 The discovery, in several small sites in the Western Desert of Egypt, of large bovid bones identified as domestic cattle and having radiocarbon dates ranging between 9,500 and 8,000 B.P. has raised the possibility that there was a separate, independent center for cattle domestication in northeast Africa (Fig. 1).2–4 However, it has not been universally accepted that these bones are from cattle or, if so, that the cattle were domestic. 相似文献
4.
Enhanced Rate of Expression and Biosynthesis of Neuropeptide Y After Kainic Acid-Induced Seizures 总被引:2,自引:0,他引:2
Romuald Bellmann Rudolf Widmann Claudia Olenik Dieter K. Meyer Dagmar Maas Josef Marksteiner Günther Sperk 《Journal of neurochemistry》1991,56(2):525-530
Recent studies have shown marked increases in brain content of neuropeptide Y (NPY) after seizures induced by intraperitoneal injection of kainic acid and after pentylenetetrazole kindling in the rat. We have now investigated possible changes in the rate of biosynthesis of NPY after kainic acid treatment, by using pulse-labeling of the peptide and by determining prepro-NPY mRNA concentrations. For pulse labeling experiments, [3H]tyrosine was injected into the frontal cortex, and the incorporation of the amino acid into NPY was determined after purifying the peptide by gel filtration chromatography, antibody affinity chromatography, and reversed-phase HPLC. At 2 and 30 days after kainic acid treatment, the rate of tyrosine incorporation was enhanced by approximately 380% in the cortex. In addition, concentrations of pre-pro-NPY mRNA were determined in four different brain areas by hybridization of Northern blots with a complementary 32P-labeled RNA probe 2, 10, 30, and 60 days after kainic acid treatment. Marked increases were observed in the frontal cortex (by up to 350% of controls), in the dorsal hippocampus (by 750%), and in the amygdala/pyriform cortex (by 280%) at all intervals investigated. In the striatum only a small, transient increase was observed. The data demonstrate increased expression of prepro-NPY mRNA and an enhanced rate of in vivo synthesis of NPY as a result of seizures induced by the neurotoxin kainic acid. 相似文献
5.
In recent years, Enterococcus faecalis has emerged as an important opportunistic nosocomial pathogen capable of causing dangerous infections. Therefore, there is an urgent need to develop novel antibacterial agents to control this pathogen. Bacteriophages have very effective bactericidal activity and several advantages over other antimicrobial agents and so far, no serious or irreversible side effects of phage therapy have been described. The objective of this study was to characterize a novel virulent bacteriophage φ4D isolated from sewage. Electron microscopy revealed its resemblance to Myoviridae, with an isometric head (74 ± 4 nm) and a long contractile tail (164 ± 4 nm). The φ4D phage genome was tested using pulsed-field gel electrophoresis and estimated to be 145 ± 2 kb. It exhibited short latent period (25 min) and a relatively small burst size (36 PFU/cell). Tests were conducted on the host range, multiplicities of infection (MOI), thermal stability, digestion of DNA by restriction enzymes, and proteomic analyses of this phage. The isolated phage was capable of infecting a wide spectrum of enterococcal strains. The results of these investigations indicate that φ4D is similar to other Myoviridae bacteriophages (for example φEF24C), which have been successfully used in phagotherapy. 相似文献
6.
David Negus Jane Burton Angela Sweed Romuald Gryko Peter W. Taylor 《Applied and environmental microbiology》2013,79(2):714-717
The poly-γ-d-glutamic acid capsule of Bacillus anthracis is a barrier to infection by B. anthracis-specific bacteriophages. Capsule expression was found to completely inhibit lytic infection by γ phage, an observation supported by the demonstration that this phage does not elaborate a hydrolase that would facilitate penetration through the protective capsule outer layer. 相似文献
7.
In this study, the sensitivities of multiplex PCR and an immuno-chromatographic methods to detect Escherichia coli O157:H7 in minced beef were compared. The detection of Escherichia coli O157:H7 in minced beef inoculated with 1-100 cells of this bacterium was possible after enrichment of culture and subsequent analysis by either of the two methods. Enrichment conditions were eight hours of incubation at 37 degrees C or 42 degrees C in a non-selective medium (Buffered Peptone Water). Multiplex PCR analysis was performed using three primer sets with analysis by gel electrophoresis. The Quix immuno-chromatographic assay which is a new kit being marketed by New Horizons Diagnostics, Columbia, MD, was used for immunological analysis of the enriched broths.The sensitivity of both tests was similar. The results depended on the concentration of the specific bacterium in the culture since the influence of the proportion of other bacteria to the E. coli O157:H7 was not observed. The data suggests that either method or used together, when coupled with an enrichment technique, could provide a rapid mean to detect the presence of this pathogen in minced meat samples. 相似文献
8.
Mikuliszyn R Kowalski W Kowalczuk K 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2002,9(1):P333-P334
There are many factors affecting pilots' +Gz-tolerance. Recently, attention of the aviation community has been focused on lay-off and it's impact on +Gz-tolerance. Pilots of the Polish Air Force (PAF) have dealt with that problem for several years now. The aim of the study was to provide insight on how lay-off periods with different duration impact +Gz-tolerance. Methods: 95 male jet pilots from the PAF participated in the study. Every one had at least two weeks lay-off period (non-medical reasons). Subjects were divided into four groups according to the length of lay-off period (2-4 weeks; 5-13 weeks; 14-26 weeks; 27-154 weeks), All pilots were subjected to a centrifuge exposure in GOR (0.1 G/s) or ROR (1.0 G/s) profiles, depending on the pre-lay-off exposure. Post-lay-off exposures were carried out directly after lay-off. 18 jet pilots without any lay-off constituted the control group. Results: The difference between pre- and post-lay-off G-tolerance limit (-0,93 +/- 0,53) was statistically significant (p<0.01) only for one group, where lay-off period ranged between two and four weeks. No statistically significant differences were found where influence of other factors like total and yearly flight hours, heart rate gain (AHR) or physical activity measured as maximal oxygen intake were considered. Conclusions: 2-4 weeks of lay-off period decreases +Gz tolerance is statistically significant manner. Subsequent increase of lay-off period does not result in mean tolerance changes for group, however in certain individuals critical decrement of +Gz tolerance occurs. Total and last year flying hours, physical fitness does not modify impact of lay-off period on +Gz tolerance. 相似文献
9.
In the last two decades, multiple aspects of the peptide YY (PYY) secretion have been investigated. Besides fat and fatty acids, many luminal nutrients in the distal intestine appear to induce PYY release. Some studies have shown that bile acid, but not nutrients, plays a crucial role in the regulation of PYY secretion. Moreover, chyme in the proximal intestine also regulates the peptide release by indirect action through humoral and neuronal factors. Gastrin, cholecystokinin, and the vagus nerve are major candidates for mediators of these indirect actions. Several growth factors have been shown to regulate PYY synthesis in mucosa of the distal intestine. This review is aimed at presenting an overview of these recent studies on PYY secretion in the distal intestine. 相似文献
10.