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91.
Bujor Alexandra Miron Anca Trifan Adriana Luca Simon Vlad Gille Elvira Miron Sorin-Dan Aprotosoaie Ana Clara 《Phytochemistry Reviews》2021,20(4):653-691
Phytochemistry Reviews - Endothelial dysfunction (impaired vasodilation, prothrombotic, proinflammatory and prooxidant states) is involved in the development of cardiovascular diseases... 相似文献
92.
It has previously been established that, in threatening situations, animals use alarm pheromones to communicate danger. There is emerging evidence of analogous chemosensory “stress” cues in humans. For this study, we collected alarm and exercise sweat from “donors,” extracted it, pooled it and presented it to 16 unrelated “detector” subjects undergoing fMRI. The fMRI protocol consisted of four stimulus runs, with each combination of stimulus condition and donor gender represented four times. Because olfactory stimuli do not follow the canonical hemodynamic response, we used a model-free approach. We performed minimal preprocessing and worked directly with block-average time series and step-function estimates. We found that, while male stress sweat produced a comparably strong emotional response in both detector genders, female stress sweat produced a markedly stronger arousal in female than in male detectors. Our statistical tests pinpointed this gender-specificity to the right amygdala (strongest in the superficial nuclei). When comparing the olfactory bulb responses to the corresponding stimuli, we found no significant differences between male and female detectors. These imaging results complement existing behavioral evidence, by identifying whether gender differences in response to alarm chemosignals are initiated at the perceptual versus emotional level. Since we found no significant differences in the olfactory bulb (primary processing site for chemosensory signals in mammals), we infer that the specificity in responding to female fear is likely based on processing meaning, rather than strength, of chemosensory cues from each gender. 相似文献
93.
Rhinolophus mehelyi (Mehely's horseshoe bat) is a vulnerable species with an increasingly fragmented distribution. In Romania, populations of
R. mehelyi have experienced a dramatic decline over the past 50 years, and the current population size is estimated at only 100 adult
individuals inhabiting almost exclusively the Limanu cave. In the present study, we investigated the genetic consequences
of population decline for the viability of the remaining population of R. mehelyi in Romania. We sequenced and analyzed a 359-bp fragment of the mitochondrial control region from the only known Romanian
population and compared it with two geographically close colonies from Bulgaria. A single haplotype was found in the Romanian
population compared to 10 in the Bulgarian population, suggesting genetic isolation. 相似文献
94.
SunCHem: an integrated process for the hydrothermal production of methane from microalgae and CO2 mitigation 总被引:1,自引:0,他引:1
Anca G. Haiduc Martin Brandenberger Sébastien Suquet Frédéric Vogel Rizlan Bernier-Latmani Christian Ludwig 《Journal of applied phycology》2009,21(5):529-541
We describe a potential novel process (SunCHem) for the production of bio-methane via hydrothermal gasification of microalgae,
envisioned as a closed-loop system, where the nutrients, water, and CO2 produced are recycled. The influence on the growth of microalgae of nickel, a trace contaminant that might accumulate upon
effluent recycling, was investigated. For all microalgae tested, the growth was adversely affected by the nickel present (1,
5, and 10 ppm). At 25 ppm Ni, complete inhibition of cell division occurred. Successful hydrothermal gasification of the microalgae
Phaeodactylum tricornutum to a methane-rich gas with high carbon gasification efficiency (68–74%) and C1–C3 hydrocarbon yields of 0.2 gC1–C3/gDM (DM, dry matter) was demonstrated. The biomass-released sulfur was shown to adversely affect Ru/C catalyst performance. Liquefaction
of P. tricornutum at short residence times around 360°C was possible without coke formation. 相似文献
95.
Anca Raˇdulescu 《Journal of theoretical biology》2009,259(2):269-279
We discuss the possibility of multiple underlying etiologies of the condition currently labeled as schizophrenia. We support this hypothesis with a theoretical model of the prefrontal-limbic system.We show how the dynamical behavior of this model depends on an entire set of physiological parameters, representing synaptic strengths, vulnerability to stress-induced cortisol, dopamine regulation and rates of autoantibody production. Malfunction of such different parameters produces similar outward dysregulation of the system, which may readily lead to diagnostic difficulties for a clinician.Techniques that provide a spectrum/profile of neural and steroid functions may be helpful in clarifying these diagnostic dilemmas. 相似文献
96.
In the house cricket,Acheta domesticus, the 110 genes per haploid genome encoding 18S and 28S rRNA are contained within rDNA repeats which are amplified during oogenesis. The 5S rRNA coding sequences of this cricket are found in two sizes of 5S DNA repeating units (measuring 2.1 and 3.0 kb). The 3.0 kb repeats account for more than 90% of the totalAcheta 5S DNA. We have determined the number of cricket 5S rRNA genes by RNA-DNA hybridization analysis: 310 5S DNA repeats/haploid genome clearly approximates the number of 18S and 28S rRNA genes. Because of the relatively low copy number of 5S rRNA genes the possibility of 5S DNA amplification in oocytes ofA. domesticus was also examined. Although amplification of rDNA is readily detectable, amplification of 5S DNA is not observed in oocytes ofA. domesticus. Unlike the genes coding for 18S and 28S rRNA which are localized at a single chromosomal site in the genome ofA. domesticus, the 5S rRNA genes occupy numerous sites distributed along the length of most chromosomes. 相似文献
97.
Gyrgy Vereb Lszl Mtyus Lszl Bene Gyrgy Panyi Zsolt Bacs Margit Balzs Jnos Matk Jnos Szllsi Rezs Gspr Sndor Damjanovich Robert E. Dale Carlo Pieri Marcel Ameloot 《Journal of molecular recognition : JMR》1995,8(4):237-246
Molecular recognition processes between cell surface elements are discussed with special reference to cell surface pattern formation of membrane-bound integral proteins. The existence, as detected by flow cytometric resonance energy transfer (Appendix), and significance of cell surface patterns involving the interleukin-2 receptor, the T-cell receptor–CD3 system, the intercellular adhesion molecule ICAM-1, and the major histocompatilibilty complex class I and II molecules in the plasma membrane of lymphocytes are described. The modulation of antigen presentation by transmembrane potential changes is discussed, and a general role of transmembrane potential changes, and therefore of icon channel activities, adduced as one of the major regulatory mechanisms of cell–cell communications. A general role in the mediation and regulation of intercellular interactions is suggested for cell-surface macromolecular patterns. The dynamic pattern of protein and lipid molecules in the plasma membrane is generated by the genetic code, but has a remarkable flexibility and may be one of the major instruments of accomodation and recognition processes at the cellular level. 相似文献
98.
99.
Activity of β-glucuronidase in Root Tips of Different Types of Transgenic Sugar Beet Plants 总被引:1,自引:0,他引:1
S. Vitha J.P. Phillips J.S. Gartland K.M.A. Gartland K. Beneš M.C. Elliott 《Biologia Plantarum》1997,40(4):531-541
Expression of the -glucuronidase (GUS) reporter gene driven by the CaMV 35S, rolC, nos and mas promoters was assessed in the tips of 12 independent clones of transgenic sugar beet (Beta vulgaris) roots. Three questions were addressed: 1) expression pattern specific for a given promoter, 2) expression pattern variability, and 3) relationship between gene expression and cell differentiation. Characteristic patterns of tissue-specific expression were distinguished for each promoter. Striking differences, however, were found between some clones, bearing the same construct. Statistical analysis of the pattern variability proved that the variability is significantly lower within the construct than between constructs. rolC-GUS clones exhibited the lowest and CaMV 35S clones the highest pattern variability. Comparisons between the four promoters showed consistent GUS activity in areas playing a key role in tissue determination (the elongation zone) where cells switch from frequent mitosis and mostly isodiametrical growth, typical for the promeristem, to rapid elongation and differentiation. All of the clones were highly GUS-positive in the elongation zone of stele. Activity was commonly localised in the stele of the maturation zone for CaMV 35S, rolC and mas-GUS clones. CaMV 35S-GUS clones were highly active in the promeristem. 相似文献
100.
Jan Naujoks Christoph Tabeling Brian D. Dill Christine Hoffmann Andrew S. Brown Mareike Kunze Stefan Kempa Andrea Peter Hans-Joachim Mollenkopf Anca Dorhoi Olivia Kershaw Achim D. Gruber Leif E. Sander Martin Witzenrath Susanne Herold Andreas Nerlich Andreas C. Hocke Ian van Driel Norbert Suttorp Sammy Bedoui Hubert Hilbi Matthias Trost Bastian Opitz 《PLoS pathogens》2016,12(2)