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21.
Guowei Lu Franck H. Lei Jean-François Angiboust Michel Manfait 《European biophysics journal : EBJ》2010,39(5):855-860
A fiber-tip-based near-field fluorescence correlation spectroscopy (FCS) has been developed for confining the detection volume
to sub-diffraction-limited dimensions. This near-field FCS is based on near-field illumination by coupling a scanning near-field
optical microscope (SNOM) to a conventional confocal FCS. Single-molecule FCS analysis at 100 nM Rhodamine 6G has been achieved
by using bare chemically etched, tapered fiber tips. The detection volume under control of the SNOM system has been reduced
over one order of magnitude compared to that of the conventional confocal FCS. Related factors influencing the near-field
FCS performance are investigated and discussed in detail. In this proof-of-principle study, the preliminary experimental results
suggest that the fiber-tip-based near-field FCS might be a good alternative to realize localized analysis at the single-molecule
level. 相似文献
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23.
Background
NOL7 is a candidate tumor suppressor that localizes to a chromosomal region 6p23. This locus is frequently lost in a number of malignancies, and consistent loss of NOL7 through loss of heterozygosity and decreased mRNA and protein expression has been observed in tumors and cell lines. Reintroduction of NOL7 into cells resulted in significant suppression of in vivo tumor growth and modulation of the angiogenic phenotype. Further, NOL7 was observed to localize to the nucleus and nucleolus of cells. However, the mechanisms regulating its subcellular localization have not been elucidated. 相似文献24.
25.
Salatiel Gonçalves-Neto Marianne Azevedo-Silva Alessandra S. M. Lemos Anete P. Souza Paulo S. Oliveira 《Entomological Science》2021,24(1):79-84
Ants (Hymenoptera: Formicidae) are dominant social insects that play important ecological roles in terrestrial ecosystems. Camponotus leydigi (Forel) is widely distributed in the Neotropical region and is frequently found in the Brazilian cerrado savanna interacting with plants and other insects. Field observations indicate that C. leydigi has a polydomous nesting habit, but little is known about the genetic relationship among workers. In this study, we identify the first nine microsatellite loci for C. leydigi that will allow further investigation on its genetic diversity. We used a microsatellite-enriched library method. According to this method, repetitive sequences are captured with (CT)8 and (GT)8 biotin-linked probes, with subsequent recovery by streptavidin magnetic-coated beads. We observed that eight loci were polymorphic. The mean (± standard error) observed and expected heterozygosities were 0.55 ± 0.23 and 0.73 ± 0.28, respectively. The rarified allelic richness ranged from 1 to 5.32. The polymorphism contents were similar to diversity estimates found in markers previously developed for other Camponotus ants. These markers will be useful for future studies on population genetics and ecology of Camponotus ants in cerrado, including nesting ecology, colony structure, dispersal and conservation. 相似文献
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27.
François Tremblay Annie-Claude Mireault Julie Létourneau Audrey Pierrat Shannon Bourrassa 《Somatosensory & motor research》2013,30(2):101-108
Recent studies suggest that sensory input generated during highly repetitive tasks can degrade the sensory representation of the hand and eventually lead to sensory and motor problems. In this study, we investigated whether early changes in tactile perception and manual dexterity could be detected in persons exposed to computer tasks. Performance in tests designed to assess tactile perception (grating orientation task for spatial acuity and roughness discrimination) and manual dexterity (grooved pegboard test) was compared between two groups of healthy individuals, matched for age, gender, and experience, who differed in terms of computer habits. One group consisted of frequent users (FU, > 2 h/day, n = 36) and the other of non or occasional users (OU, < 2 h/day, n = 28). Comparison of performance between groups with subjects sorted by gender revealed significant differences ( t -test, p < 0.05) in female, but not male, participants. Grating resolution thresholds at the tip on the second and fifth digits were, on average, 40% higher in female FU ( n = 13) than in female OU ( n = 10) and performance scores on the dexterity test were significantly higher for the left hand. The results of this study indicate that early signs of deterioration in hand function can be present in persons constantly exposed to computer tasks and that these signs are more readily apparent in women than in men. The loss of tactile spatial acuity found in female FU possibly reflect an early consequence of the degraded sensory representation of the hand resulting from constant repetitions of fine motor tasks. 相似文献
28.
Carole-Anne Lefebvre Elsa Forcellini Sophie Boutin Marie-France Côté René C.-Gaudreault Patrick Mathieu Patrick Lagüe Jean-François Paquin 《Bioorganic & medicinal chemistry letters》2017,27(2):299-302
The synthesis of two series of novel substituted pyrimidine derivatives bearing a sulfamide group have been described and their in vitro cancer growth inhibition activities have been evaluated against three human tumour cell lines (HT-29, M21, and MCF7). In general, growth inhibition activity has been enhanced by the introduction of a bulky substituent on the aromatic ring with the best compound having GI50 < 6 μM for all the human tumour cell lines. The MCF7 selective compounds were evaluated on four additional human invasive breast ductal carcinoma cell lines (MDA-MB-231, MDA-MB-468, SKBR3, and T47D) and were selective against T47D cell line in all cases except one, suggesting a potential antiestrogen activity. 相似文献
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30.
The roles of allopatric fragmentation and niche divergence in intraspecific lineage diversification in the common midwife toad (Alytes obstetricans) 下载免费PDF全文