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The single‐cell screening has attracted great attentions in advanced biomedicine and tissue biology, especially for the early disease diagnosis and treatment monitoring. In this work, by using a specific‐designed fiber probe with a flat facet, we propose an “optical fan” strategy to screen K562 cells at the single‐cell level from a populations of RBCs. After the 980‐nm laser beam injected into the fiber probe, the RBCs were blown away but holding target K562 cells in place. Further, multiple leukemic cells can be screened from hundreds of red blood cells, providing an efficient approach for the cell screening. The experimental results were interpreted by the numerical simulation, and the stiffness of optical fan was also discussed.  相似文献   
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Zhang  Jiaxian  Jing  Yu  Zhang  Hu  Liu  Ping 《Amino acids》2021,53(9):1441-1454

l-arginine is a versatile amino acid with a number of bioactive metabolites. Increasing evidence implicates altered arginine metabolism in the aging and neurodegenerative processes. The present study, for the first time, determined the effects of sex and estrous cycle on the brain and blood (plasma) arginine metabolic profile in naïve rats. Female rats displayed significantly lower levels of l-arginine in the frontal cortex and three sub-regions of the hippocampus when compared to male rats. Moreover, female rats had significantly higher levels of l-arginine and γ-aminobutyric acid, but lower levels of l-ornithine, agmatine and putrescine, in plasma relative to male rats. The observed sex difference in brain l-arginine appeared to be independent of the enzymes involved in its metabolism, de novo synthesis and blood-to-brain transport (cationic acid transporter 1 protein expression at least), as well as circulating l-arginine. While the estrous cycle did not affect l-arginine and its metabolites in the brain, there were estrous cycle phase-dependent changes in plasma l-arginine. These findings demonstrate the sex difference in brain l-arginine in the estrous cycle-independent manner. Since peripheral blood has been increasingly used to identify biomarkers of brain pathology, the influences of sex and estrous cycle on blood arginine metabolic profile need attention when experimental research involves female rodents.

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The chiral construction of complex supramolecular systems is receiving much interest, especially with achiral building units. In this paper, we reported the helix supramolecular structure of an achiral rhenium complex crystal, [Re(CO)3(C16H12N2)(MeCN)] · ClO4, which was formed by coordination of Re(CO)5Cl with 2-methenepyridyl-1-aminonaphthalene and acetonitrile. X-ray diffraction analysis suggests that homohelical column metallosupramolecular architecture results from the array of the six-coordinated Re around and along a line: the helical axis in chiral P1211 (No. 4) space group. There is rare example of constructing helical architectures with both coordinated and hydrogen bonds from achiral units. The helical self-assembly process is induced by the intrastrand interaction and crystal growth. Here, the perchlorate acts as both the counter ion and the bridge linking the neighboring coordinated parts together by weak non-covalent interaction. Furthermore, the two-dimensional arrangement adopts double-edged axe-shaped motif, which is different from the common herringbone or brick-wall pattern in coordination polymers. Our investigation introduced the special arrangement model into complicated helical architecture, especially homochiral single-colony.  相似文献   
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Pescadillo was initially identified in a genetic screen for mutations that affect embryonic develop-ment of the zebrafish Daniorerio[1]. Pescadillo-/- ze-brafish mutants showed abnormal embryonic devel-opment such as reduced brain, eye size and a lack of extension of the jaw on developmental day 3. Further study showed that the Pescadillo protein is mainly distributed in tissues containing a significant number of proliferating cells and dramatically elevated in ma-lignant human astrocytomas an…  相似文献   
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Significant improvements of plasma performance after ICRF boronization have been achieved in the full range of HT-7 operation parameters. Electron power balance is analyzed in the steady state ohmic discharges of the HT-7 tokamak. The ratio of the total radiation power to ohmic input power increases with increasing the central line-averaged electron density, but decreases with plasma current. It is obviously decreased after wall conditioning. Electron heat diffusivity χe deduced from the power balance analysis is reduced throughout the main plasma after boronization. χe decreases with increasing central line-averaged electron density in the parameter range of our study. After boronization, the plasma current profile is broadened and a higher current can be easily obtained on the HT-7 tokamak experiment. It is expected that the fact that the bootstrap current increases after boronization will explain these phenomena. After boronization, the plasma pressure gradient and the electron temperature near the boundary are larger than before, these factors influencing that the ratio of bootstrap current to total plasma current increases from several percent to above 10%.  相似文献   
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