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81.
82.
Optical extinction resonant properties of the silver rhombic plasmonic nanoparticles in visible regime were investigated by means of finite difference time domain method algorithm-based computational numerical calculation. Considering aspect ratio (a/b) of the x- and y-axes of the rhombic particles, the polarization in different angles of the incident light, and the index of the surrounding medium, we studied the extinction properties of a single rhombus. The simulation results show that there is only one clear resonance peak in the visible regime, and the corresponding plasmon mode is a dipolar plasmon mode. Along the direction of the light polarization, with the increase of the aspect ratio (a/b), red shift of the resonant peak occurs and the extinction efficiency increases accordingly. With the polarization angle varying from 0° to 90°, the resonance peaks show a small blue shift and the corresponding extinction efficiency varies slightly consequently. The tailoring ability of the resonance frequency is shown to be improved due to a unique interaction of local geometry with surface charge distributions. 相似文献
83.
Zhongkai Hao Qi Chen Wenrui Dai Yinjuan Ren Yin Zhou Jinlin Yang Sijie Xie Yanbin Shen Jihong Wu Wei Chen Guo Qin Xu 《Liver Transplantation》2020,10(10)
Developing a titanium dioxide (TiO2)‐based anode with superior high‐rate capability and long‐term cycling stability is important for efficient energy storage. Herein, a simple one‐step approach for fabricating blue TiO2 nanoparticles with oxygen vacancies is reported. Oxygen vacancies can enlarge lattice spaces, lower charge transfer resistance, and provide more active sites in TiO2 lattices. As a result, this blue TiO2 electrode exhibits a highly reversible capacity of 50 mAh g?1 at 100 C (16 800 mA g?1) even after 10 000 cycles, which is attributable to the combination of surface capacitive process and remarkable diffusion‐controlled insertion revealed by the kinetic analysis. The strategy of employing oxygen‐deficient nanoparticles may be extended to the design of other robust semiconductor materials as electrodes for energy storage. 相似文献
84.
85.
Syk is a 72-kDa protein-tyrosine kinase that regulates signaling through multiple cell surface receptors including those for antigens, immunoglobulins and proteins of the extracellular matrix. As part of its function, Syk binds a variety of downstream effectors through interactions that are often mediated by motifs that recognize phosphotyrosines. In a search for novel Syk-interacting proteins by yeast two-hybrid analysis, we identified tensin2 as a Syk-binding protein. Syk interacts with a fragment of tensin2 located near the C-terminus that contains SH2 and PTB domains. In epithelial cells, tensin2 localizes both to focal adhesions and to large cytoplasmic puncta. It is within these punctuate structures that Syk and tensin2 are co-localized. The clustering of Syk within these structures leads to its phosphorylation on tyrosine. 相似文献
86.
Hongwei Wan Yong Zhou Ping Yang Bo Chen Guiqing Jia Xiaoting Wu 《Cancer epidemiology》2010,34(1):66-72
Background: Studies investigating the association between genetic polymorphism of glutathione S-transferase T1 (GSTT1) and risk of colorectal cancer have reported conflicting results. In order to clarify the effect of GSTT1 polymorphism on the risk of developing colorectal cancer, we carried out a meta-analysis using published data to obtain more precise estimates of risk. Methods: Electronic searches of PubMed and EMBASE were conducted to select studies for this meta-analysis. Papers were included if they were observational studies investigating the association between GSTT1 polymorphism and colorectal cancer risk. The principal outcome measure was the odds ratio (OR) with 95% confidence interval (CI) for the risk of colorectal cancer associated with GSTT1 null genotype. Results: We identified 30 eligible studies, which included 7635 cases and 12,911 controls. The combined results based on all studies showed that there was a statistically significant link between GSTT1 null genotype and colorectal cancer risk (OR = 1.20, 95% CI = 1.03–1.40). In the analysis of ethnic groups, we observed distinct differences associated with GSTT1 null genotype, the pooled odds ratios for the GSTT1 polymorphism were 1.32 in Caucasians (95% CI = 1.09–1.58) and 1.03 in Asians (95% CI = 0.81–1.32). As far as concerned the interaction between GSTT1 genotype and colorectal cancer risk in relation to smoking history, there was no increase in risk for smokers or nonsmokers with the GSTT1 null genotype (smokers: OR = 1.13, 95% CI = 0.80–1.60, nonsmokers: OR = 0.99, 95% CI = 0.71–1.38). When stratifying by the location of colorectal cancer, we found that there was a statistically significant link in rectal cancer (OR = 1.50, 95% CI = 1.09–2.07), but not in colon cancer (OR = 1.33, 95% CI = 0.94–1.88). No associations could be detected between null GSTT1 polymorphism and age, sex, tumor stage and differentiation. Conclusion: Our current study demonstrates that GSTT1 null genotype is associated with an increased risk of colorectal cancer, specifically, among Caucasians. 相似文献
87.
Zhi Qian Zeyuan Zhong Shuo Ni Dejian Li Fangxue Zhang Ying Zhou Zhanrong Kang Jun Qian Baoqing Yu 《Journal of cellular and molecular medicine》2020,24(17):10112-10127
Postmenopausal Osteoporosis (PMOP) is oestrogen withdrawal characterized of much production and activation by osteoclast in the elderly female. Cytisine is a quinolizidine alkaloid that comes from seeds or other plants of the Leguminosae (Fabaceae) family. Cytisine has been shown several potential pharmacological functions. However, its effects on PMOP remain unknown. This study designed to explore whether Cytisine is able to suppress RANKL‐induced osteoclastogenesis and prevent the bone loss induced by oestrogen deficiency in ovariectomized (OVX) mice. In this study, we investigated the effect of Cytisine on RAW 264.7 cells and bone marrow monocytes (BMMs) derived osteoclast culture system in vitro and observed the effect of Cytisine on ovariectomized (OVX) mice model to imitate postmenopausal osteoporosis in vivo. We found that Cytisine inhibited F‐actin ring formation and tartrate‐resistant acid phosphatase (TRAP) staining in dose‐dependent ways, as well as bone resorption by pit formation assays. For molecular mechanism, Cytisine suppressed RANK‐related trigger RANKL by phosphorylation JNK/ERK/p38‐MAPK, IκBα/p65‐NF‐κB, and PI3K/AKT axis and significantly inhibited these signalling pathways. However, the suppression of PI3K‐AKT‐NFATc1 axis was rescued by AKT activator SC79. Meanwhile, Cytisine inhibited RANKL‐induced RANK‐TRAF6 association and RANKL‐related gene and protein markers such as NFATc1, Cathepsin K, MMP‐9 and TRAP. Our study indicated that Cytisine could suppress bone loss in OVX mouse through inhibited osteoclastogenesis. All data provide the evidence that Cytisine may be a promising agent in the treatment of osteoclast‐related diseases such as osteoporosis. 相似文献
88.
Wan YJ Zhang YL Zhou ZR Jia RX Li M Song H Wang ZY Wang LZ Zhang GM You JH Wang F 《Theriogenology》2012,78(3):583-592
The objective was to investigate the effects of the transgenic donor cell synchronization method, oocyte sources, and other factors, on production of hLF-gene nucleus transfer dairy goats. Three transfected cell lines from ear biopsies from three 3-mo-old Saanen dairy goats (designated Number 1, Number 2, and Number 3, respectively) were selected as karyoplast donors for somatic cell nuclear transfer (SCNT) after detailed identification (including PCR and sequencing of PCR products). In donor cell cycle synchronization studies, the apoptosis rate of hLF transgenic fibroblasts was not different (P > 0.05) after 3 days of serum starvation or 2 days of contact inhibition. Additionally, there was no effect (P > 0.05) on developmental capacity of reconstructed embryos; however, the kidding rate of recipients in the serum starvation group was higher than that in the contact inhibition group (18 vs. 0%, respectively). The production efficiency of the transgenic cloned goats using donor cells from the Number 1 dairy goat cell line was higher than those using the Number 2 and the Number 3 cell lines (kidding rates were 18, 2, and 0%, respectively, P < 0.05). The oocyte source did not significantly affect the pregnancy rate of hLF-transgenic cloned dairy goats, but more fetuses were aborted when using in vitro matured oocytes compared to in vivo matured oocytes. In summary, utilizing transfected 3-mo-old dairy goat fibroblasts as donor cells, seven live offspring were produced, and the hLF gene was successfully integrated. This study provided additional insights into preparation of donor cells and recipient oocytes for producing transgenic cloned goats through SCNT. 相似文献
89.
The biosynthesis of caldariellaquionone (CQ) was studied in species of Sulfolobus by measuring the incorporation of stable isotopically labeled tyrosines into CQ. By feeding a series of tyrosines labeled with deuterium or 13C and then measuring the extent and position at which label was incorporated into CQ by mass spectrometry, it was shown that more than 95% of the label was incorporated into the benzo[b]thiophen-4,7-quinone moiety of CQ. From the labeling experiments, it is concluded that the benzo[b]thiophen-4,7-quinone is derived as an intact unit from all of the carbons of tyrosine except C-1. 相似文献
90.