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91.
Coček A Hahn A Mártonová J Ambruš M Dohnalová A Nedbalová M Jandová A 《Electromagnetic biology and medicine》2012,31(2):166-177
Our research thus far has concerned the impact of external electromagnetic fields (50 Hz) and low (0.01-10 mT) induction on adherence capabilities of T lymphocytes obtained from the blood of patients with head and neck tumors. We know that the in vitro adherence capability of T lymphocytes towards surfaces in cancer patients is less than that of control. Previously, we have found that exposure to electromagnetic fields (50 Hz/0.01-10 mT) increases the capability of T lymphocytes, in larynx/pharynx cancer patients, to adhere in vitro to surfaces, achieving almost physiological values, in not only pre-treatment patients but also those receiving treatment in the course of follow-up. The capability of T lymphocytes in controls (voluntary blood donors) to adhere to surfaces was also increased (50 Hz/0.01-0.5 mT). The present study concentrates on the significance of the level of electromagnetic field induction in order to determine whether low induction values can restore T lymphocytes adherence capabilities. Testing a subset of 20 patients showed a statistically significant difference (p<0.05) in the in vitro adherence capacity of T lymphocytes between both 0.01 and 0.05, and 0.1 mT induction levels. In the control group (patients diagnosed with chronic sensorineural hearing loss) there was even a statistically significant difference between induction values of 0.05 and 0.01 mT. A statistically significant difference (p<0.05) was also achieved with induction levels of 1 and 10 mT compared to 0.5, 0.1, and 0.05 mT, respectively. Therefore, we concluded that lower induction values resulted in a more biologically significant response. 相似文献
92.
Petr?SmykalEmail author Michala?Chaloupská Michael?Bariotakis Lucie?Mare?ková Andrey?Sinjushin Ivan?Gabrielyan Janna?Akopian Cengiz?Toker Gregory?Kenicer Miloslav?Kitner Stergios?Pirintsos 《Plant Systematics and Evolution》2017,303(3):267-282
Vavilovia formosa is one of five genera in tribe Fabeae, (Fabaceae, Leguminosae) with close phylogenetic relationships to Pisum. It grows in subalpine and alpine levels in Armenia, Azerbaijan, Georgia, Iran, Iraq, Lebanon, Russia and Turkey and is recognized as an endangered and protected plant. This study was conducted to reveal its intraspecific variability, as well as to predict the past, extant and future species distribution range. We analysed 51 accessions with common phylogenetic markers (trnF-trnL, trnS-trnG, matK, rbcL, psbA-trnH and ITS). These represent in total up to 2551 bp of chloroplast and 664 bp of nuclear sequences per sample. Two populations from Turkey and Armenia were analysed for genetic diversity by AFLP. Leaf morphometry was conducted on 1457 leaflets from 43 specimens. Extracted bioclimatic parameters were used for niche-modelling approach. Analysis of cpDNA revealed two haplotypes, 12 samples from Armenia, Daghestan, Nakhichevan and Iran belonged to H1 group, while 39 samples of all Turkish and part of Armenian were in H2 group. The mean intrapopulation diversity based on AFLP was low (H E = 0.088) indicating limited outcrossing rate. A significantly positive correlation between geographical latitude and leaf area (\(\rho\) = 0.527, p < 0.05) was found. Niche modelling has shown temporal variation of predicted occurrence across the projected time periods. Vavilovia formosa has suffered a range reduction following climate warming after last glacial maximum, which classify this species as cold-adapted among the Fabeae species as well as a glacial relict. 相似文献
93.
Koplík R Borková M Mestek O Komínková J Suchánek M 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,775(2):179-187
Fractionation of soluble species of P, Mn, Fe, Co, Ni, Cu, Zn, Se and Mo in pea and lentil seeds was made by on-line hyphenation of size-exclusion chromatography (SEC) and inductively coupled plasma mass spectrometry. Seed samples were extracted with 0.02 mol l(-1) Tris-HCl buffer solution, pH 7.5. SEC was performed on Superdex 75 and Superdex Peptide columns (300 x 10 mm) with the same buffer solution as the mobile phase. Monitoring of oxide ion 47(PO)+ was used for detection of phosphorus compounds. Other elements were detected as ions of 55Mn, 57Fe, 59Co, 62Ni, 65Cu, 66Zn, 82Se and 95Mo nuclides. Elements in individual elution zones were quantified using external calibration. Complete chromatographic recoveries of elements were found in cases of phosphorus, nickel and copper. Substantial parts of manganese and zinc, as well as traces of cobalt, selenium and molybdenum are retained on the column. Injection of EDTA solution removes these elements from the column. Chromatographic profiles of pea and lentil samples are very similar for all elements except Mo. Main element species in the high-molecular-mass region (approx. 190,000 rel. mol. mass unit) were detected in case of Fe. Low-molecular-mass species (<2000 rel. mol. mass unit) as major element forms are typical for Cu and Zn. 相似文献
94.
Frollo I Banic B Mravec B Jurani M Greksak M Macho L Kvetnansky R 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2002,9(1):P339-P340
Electro-mechanical equipment for multiple blood withdrawal from small experimental animals applied to a centrifuge with maximal 6g gravitational overloading has been developed and tested. The equipment consists of a transmitter and receiver equipped by microcomputers. Active rotor stepping motors are driving four pairs of syringes. It is also possible to measure the instantaneous gravitational force using an accelerometric transducer. This telemetrically regulated blood sampling allows studying selective effects of hypergravity during centrifugation. It can be also used for study of microgravity effects in the animal organism during space flights for the understanding of the mechanism of the changes of the activity of neuroendocrine system and metabolic processes. 相似文献
95.
Kopecek M Sos P Brunovsky M Bares M Stopkova P Krajca V 《Neuro endocrinology letters》2007,28(4):524-526
We present a case report of a 37-year old woman diagnosed with depressive disorder, first episode, who was admitted into a psychiatric hospital after a failed suicidal attempt. She responded to antidepressant therapy, as evidenced by a >50% reduction in MADRS total score. She was discharged after 4 weeks of treatment, denying any suicidal ideations. The following day the patient committed suicide; she burned herself to death. It is very likely that the patient dissimulated her symptoms and ideations. Subsequently, her quantitative EEG records were retrospectively analyzed. An increase of prefrontal theta cordance value after the first week of mirtazapine therapy was found. Recently three small studies have revealed that decrease of prefrontal theta cordance after 1 week of antidepressant administration can predict clinical response in patients with unipolar depression. In our previous study the absence of a decreased theta prefrontal cordance was associated with lack of treatment response with NPV 1.0 (Bares et al., 2007). Thus, we hypothesize that prefrontal theta cordance could become an objective marker of change of depressive symptoms, independent of patients' compliance and symptom dissimulation, more precise than objective and self-rated depression rating scales. 相似文献
96.
Alica Chroňáková Brigitte Schloter-Hai Viviane Radl David Endesfelder Christopher Quince Dana Elhottová Miloslav ?imek Michael Schloter 《PloS one》2015,10(8)
Archaea and bacteria are important drivers for nutrient transformations in soils and catalyse the production and consumption of important greenhouse gases. In this study, we investigate changes in archaeal and bacterial communities of four Czech grassland soils affected by outdoor cattle husbandry. Two show short-term (3 years; STI) and long-term impact (17 years; LTI), one is regenerating from cattle impact (REG) and a control is unaffected by cattle (CON). Cattle manure (CMN), the source of allochthonous microbes, was collected from the same area. We used pyrosequencing of 16S rRNA genes to assess the composition of archaeal and bacterial communities in each soil type and CMN. Both short- and long- term cattle impact negatively altered archaeal and bacterial diversity, leading to increase of homogenization of microbial communities in overwintering soils over time. Moreover, strong shifts in the prokaryotic communities were observed in response to cattle overwintering, with the greatest impact on archaea. Oligotrophic and acidophilic microorganisms (e.g. Thaumarchaeota, Acidobacteria, and α-Proteobacteria) dominated in CON and expressed strong negative response to increased pH, total C and N. Whereas copiotrophic and alkalophilic microbes (e.g. methanogenic Euryarchaeota, Firmicutes, Chloroflexi, Actinobacteria, and Bacteroidetes) were common in LTI showing opposite trends. Crenarchaeota were also found in LTI, though their trophic interactions remain cryptic. Firmicutes, Bacteroidetes, Methanobacteriaceae, and Methanomicrobiaceae indicated the introduction and establishment of faecal microbes into the impacted soils, while Chloroflexi and Methanosarcinaceae suggested increased abundance of soil-borne microbes under altered environmental conditions. The observed changes in prokaryotic community composition may have driven corresponding changes in soil functioning. 相似文献
97.
The influence of plant transpiration on the entropy exchange was quantified as associated with the degradation of solar energy
on the Earth’s surface covered by plants. Two surfaces were studied: (1) productive surface — plant transpiration taken as
equal to the potential one, (2) non-productive surface — plant transpiration taken as equal to zero. The entropy exchanges
associated with the absorption of solar radiation and with the conversion of absorbed solar radiation into the sensible heat
and latent heat were taken into account. These processes were examined in the experimental watershed Liz (828–1074 m a.s.l.)
located in the Bohemian Forest (Czech Republic). We found that in the growing season 1992 the net entropy exchange in humid
hydrologic period (the Earth’s surface is productive) was considerably higher than in the arid one (the Earth’s surface was
productive in 39% of days, and non-productive in 61% of days). Considering that the biotic effect on the Earth’s functioning
can be measured with the help of the net entropy exchange, we can assume that the theory that biotic activities — represented
by plant transpiration here — are the cause of the self-organizing processes in Earth’s environment is proved in the watershed
scale.
Presented at the International Conference on Bioclimatology and Natural Hazards, Poľana nad Detvou, Slovakia, 17–20 September
2007. 相似文献
98.
Miloslav Devetter 《Biologia》2007,62(2):222-224
Soil rotifers of the Kokořínsko Protected Landscape Area (Central and Northern Bohemia, Czech Republic) were investigated
in August, 2004. This is the first investigation of the soil rotifers in the area. Altogether 25 rotifer taxa were found at
five sites. Mniobia symbiotica, M. variabilis, Macrotrachela habita, M. oblita, Habrotrocha flaviformis, H. bidens and Ceratotrocha cornigera were the most abundant species. These are the first findings of Mniobia variabilis and Macrotrachela oblita in the Czech Republic. Total rotifer abundances varied from 67 to 647 × 103 ind. m−2. 相似文献
99.
100.
Kaniakova M Krausova B Vyklicky V Korinek M Lichnerova K Vyklicky L Horak M 《The Journal of biological chemistry》2012,287(31):26423-26434
N-methyl-d-aspartate (NMDA) receptors are glutamate ionotropic receptors that play critical roles in synaptic transmission, plasticity, and excitotoxicity. The functional NMDA receptors, heterotetramers composed mainly of two NR1 and two NR2 subunits, likely pass endoplasmic reticulum quality control before they are released from the endoplasmic reticulum and trafficked to the cell surface. However, the mechanism underlying this process is not clear. Using truncated and mutated NMDA receptor subunits expressed in heterologous cells, we found that the M3 domains of both NR1 and NR2 subunits contain key amino acid residues that contribute to the regulation of the number of surface functional NMDA receptors. These key residues are critical neither for the interaction between the NR1 and NR2 subunits nor for the formation of the functional receptors, but rather they regulate the early trafficking of the receptors. We also found that the identified key amino acid residues within both NR1 and NR2 M3 domains contribute to the regulation of the surface expression of unassembled NR1 and NR2 subunits. Thus, our data identify the unique role of the membrane domains in the regulation of the number of surface NMDA receptors. 相似文献