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191.
With the help of quantum mechanical calculations, we have examined the series of central system X(ML)3 +(X = O, S, Se; M = Au, Ag, Cu). Using a scalar–relativistic density functional approach, we studied the geometry structures, Mulliken populations and charges of the systems. Structure parameters of the experimental systems are reproduced well with Xα method. The metallophilic interaction energy is analyzed and decomposed. For the systems with different central atoms and different metal atoms, the nature of the metallophilic attraction interaction is analyzed.  相似文献   
192.
UiO-66-NH2 nanocomposite was post-modified with 4-mercaptophenylboronic acid (MPBA) by the method of in situ hybridization reaction. The hybrid boronate affinity material UiO-NH2@P (TEPIC-co-MPBA) was characterized by scanning electron microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy. The material was applied as fluorescent probe for the detection of cis-diol containing compounds based on the boronate affinity mechanism, and exhibited high specific selectively. The proposed method exhibited good linearity for the detection of catechol in the range of 0.50 to 8.00 μg ml−1. The detection limit was 0.13 μg ml−1. The tactic was successfully applied to analyze the total polyphenols in tea beverages for catechol, and relative recovery was in 98.86–106.00%. Therefore, this work provided a promising strategy for the recognition of cis-diol containing compounds.  相似文献   
193.
Biomechanics and Modeling in Mechanobiology - A better understanding of the time-dependent biomechanical behaviour of the biphasic hip articular cartilage (AC) under physiological loadings is...  相似文献   
194.
Wu  Yuru  Chen  Jiehao  Wei  Wenyan  Miao  Yujia  Liang  Chao  Wu  Jianing  Huang  Xiaoli  Yin  Lizi  Geng  Yi  Chen  Defang  Ouyang  Ping 《International microbiology》2022,25(3):605-613
International Microbiology - Aeromonas hydrophila is a common pathogen in fish that has caused severe economic losses in aquaculture worldwide. With the emergence of bacterial resistance, it is...  相似文献   
195.
196.
Protein regulator of cytokinesis 1 (PRC1) has been reported in correlation with various malignancies. Functionality of PRC1 in nasopharyngeal carcinoma (NPC) was investigated, in perspective of long noncoding RNA (lncRNA) regulatory circuitry. Aberrant expressed messenger RNA and lncRNA were screened out from the Gene Expression Omnibus microarray database. NPC cell line CNE-2 was adopted for in vitro study and transfected with mimic or short hairpin RNA of miR-194-3p and PTPRG-AS1. The radioactive sensitivity, cell viability, migration, invasion, and apoptosis were detected. PTPRG-AS1 and PRC1 were upregulated in NPC, whereas miR-194-3p was downregulated. PTPRG-AS1 was found to specifically bind to miR-194-3p as a competing endogenous RNA and miR-194-3p targets and negatively regulates PRC1. Overexpressed miR-194-3p or silenced PTPRG-AS1 resulted in enhanced sensitivity to radiotherapy and cell apoptosis along with suppressed cell migration, invasion and proliferation in NPC. Furthermore, impaired tumor formation was also caused by miR-194-3p overexpression or PTPRG-AS1 suppression through xenograft tumor in nude mice. In our study, PTPRG-AS1/miR-194-3p/PRC1 regulatory circuitry was revealed in NPC, the mechanism of which can be of clinical significance for treatment of NPC.  相似文献   
197.
Collagen is one of the most abundant and important proteins in the human body. Human collagen type III (hCOL3A1) belongs to the fibril-forming collagens and is widely distributed in extensible connective tissue like skin, internal organs, or the vascular system. It plays key roles in wound healing, collagen fibrillogenesis, and normal cardiovascular development in human. The charged residues are considered to be an important characteristic of hCOL3A1, especially for collagen binding and recognition. Here we found that a triple helix fragment of hCOL3A1, Gly489-Gly510, contained multiple charged residues, as well as representative Glu-Lys-Gly and Glu-Arg-Gly charged triplets. We solved the crystal structure of this new fragment to a high-resolution of 1.50?Å and identified some important conformations of this new triple-helix region, including strong hydrogen bonds in interchain and interhelical interactions in addition to obvious flexible bending for the triple helix. We also found that the synthetic collagen peptides around this region exhibited potent activities through integrin-mediated peptide-membrane interaction. We then developed a method to produce a recombinant protein consisting of 16 tandem repeats of the triple-helix fragment of hCOL3A1 with strong activity without cytotoxicity. These results provide a strong base for further functional studies of human collagen type III and the method developed in this study can be applied to produce hCOL3A1-derived proteins or other tandem-repeat proteins with membrane adhesion activity.  相似文献   
198.
In this study, a cell line, designated as Acipenser ruthenus testis (ART), was successfully established from testis tissues of the sterlet Acipenser ruthenus and characterized by studying and comparing the expression of specific genes between the cell line and the parent gonad tissues. The results suggested that the developed ART cell line was composed of a mixture of germ cells and somatic cells. Ploidy analysis indicated that the cell line exhibited a high degree of genetic stability and that the cells remained in a good proliferating state after being subcultured to passage 80.  相似文献   
199.
Abrupt drought–flood alternation (T1) is a meteorological disaster that frequently occurs during summer in southern China and the Yangtze river basin, often causing a significant loss of rice production. In this study, the response mechanism of yield decline under abrupt drought–flood alternation stress at the panicle differentiation stage was analyzed by looking at the metabolome, proteome as well as yield and physiological and biochemical indexes. The results showed that drought and flood stress caused a decrease in the yield of rice at the panicle differentiation stage, and abrupt drought–flood alternation stress created a synergistic effect for the reduction of yield. The main reason for the decrease of yield per plant under abrupt drought–flood alternation was the decrease of seed setting rate. Compared with CK0 (no drought and no flood), the net photosynthetic rate and soluble sugar content of T1 decreased significantly and its hydrogen peroxidase, superoxide dismutase, peroxidase activity increased significantly. The identified differential metabolites and differentially expressed proteins indicated that photosynthesis metabolism, energy metabolism pathway and reactive oxygen species response have changed strongly under abrupt drought–flood alteration stress, which are factors that leads to the rice grain yield reduction.  相似文献   
200.

As grassroots user/survivor movements gained traction across the Global North, mental health activists have provided mutual aid for those who consider themselves to be negatively affected by their psychiatrization experiences and for those in search of alternative (non-biopsychiatric) frameworks for understanding mental diversity. In addition to in-person support groups, digital communication has become an integral organizing mechanism for mutual aid actions to support those in mental distress. However, activists have often found both digital and face-to-face communication to be quite taxing to their own well-being—as they negotiate personal capacity to respond to collective needs and practice self-care through limiting their engagements in radical mental health communities. While engaging in an ethnography with a mutual aid community in the United States, I explored the use of “boundary formation” to set parameters for social engagement within digital support and face-to-face encounters. Semi-structured interviews with 14 participants, focus group discussions, participatory observation, and an analysis of digital communication revealed that group members often discussed setting personal boundaries as an act of self-care, a recognition of the pitfalls associated with engaging in group dynamics during times of mental distress, and as a practice to ensure communal longevity. The ways that participants discussed and enacted boundary formation are analyzed in this paper as a way of blocking, redirecting, and restructuring digital and in-person engagements within mutual aid assemblages.

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