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991.
Dendritic cells (DCs) are professional antigen-presenting cells that play an important role in anti-tumour immunity. Endothelial-like differentiation of DCs is an interesting phenomenon. The specific role of vascular endothelial growth factor-A (VEGF-A) on the differentiation of immature DCs (iDCs) and mature DCs (mDCs) is worth further research. Here, we show that VEGF-A can induce iDCs to differentiate into endothelial-like cells (ELCs). But it has no obvious influence on mDCs. In the process of endothelial-like differentiation of iDCs, a sustained activation of extracellular signal-regulated kinase (ERK1/2) and cAMP response element binding protein (CREB) was detected. VEGF-A induced the activation of ERK1/2, and led to the nuclear translocation of phosphorylation ERK1/2. Incubation of iDCs with the ERK1/2 upstream kinase MEK1/2 inhibitor PD98059, blocked the phosphorylation of ERK1/2 and CREB as well as the endothelial-like differentiation of iDCs. These data suggest that VEGF-A induces endothelial-like differentiation of iDCs not mDCs through ERK1/2 signalling pathway.  相似文献   
992.
Nickel oxide microfibers (NiO-MFs) were directly immobilized onto the surface of fluorine tin oxide (FTO) electrode by electrospinning and calcination without using any immobilization matrix for nonenzymatic glucose sensor. Morphology and structure of NiO-MFs were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction pattern (XRD). The electrochemical and electrocatalytic performances of the NiO-MFs modified electrodes prepared at different calcination temperatures ranging from 300 to 500°C were evaluated by cyclic voltammetry (CV). The CV results have demonstrated that NiO-MFs modified electrode prepared at 300°C displayed distinct increase in electrocatalytic activity toward the oxidation of glucose, which is explored to develop an amperometric nonenzymatic glucose sensor. The NiO-MFs prepared at 300°C based amperometric nonenzymatic glucose sensor has ultrasensitive current (1785.41 μA mM(-1) cm(-2)) response and low detection limit of 3.3×10(-8) M (signal/noise ratio (S/N)=3), which are among the best values reported in literature. Additionally, excellent selectivity and stability have also been obtained.  相似文献   
993.
The doublesex gene regulates the somatic sexual development of Bombyx mori by alternatively splicing into sex-specific splice forms. In our previous study, the splice form Bmdsx F7 , which encodes the BmDSXF5 protein, was found to be expressed in a female-specific manner and to contain a novel C-terminus. In this study, we aimed to investigate the role of this C-terminus. Two transgenic lines, L1 and L2, were constructed to ectopically express Bmdsx F7 in males. Phenotype and W chromosome-specific polymerase chain reaction (PCR) analysis showed that developmental abnormalities and sex reversal did not occur. Moreover, the sex ratio was also normal. Quantitative PCR revealed that the expression levels of SP1 and Vg were upregulated in the fat body of transgenic males. Additionally, the expression level of PBP was downregulated in the antenna of transgenic males. The results suggested that the C-terminus of BmDSXF5 functioned as a regulatory domain during regulation of downstream target gene expression and that BmDSXF5 participated in the sexual development of somatic cells together with other DSX proteins in B. mori.  相似文献   
994.
995.
Leptosphaeria maculans and L. biglobosa are closely related sibling fungal pathogens that cause phoma leaf spotting, stem canker (blackleg) and stem necrosis of oilseed rape (Brassica napus). The disease is distributed worldwide, and it is one of the main causes of considerable decrease in seed yield and quality. Information about the time of ascospore release at a particular location provides important data for decision making in plant protection, thereby enabling fungicides to be used only when necessary and at optimal times and doses. Although the pathogens have been studied very extensively, the effect of climate change on the frequencies and distributions of their aerially dispersed primary inoculum has not been reported to date. We have collected a large dataset of spore counts from Poznan, located in central-west part of Poland, and studied the relationships between climate and the daily concentrations of airborne propagules over a period of 17 years (1998–2014). The average air temperature and precipitation for the time of development of pseudothecia and ascospore release (July–November), increased during the years under study at the rates of 0.1 °C and 6.3 mm per year. The day of the year (DOY) for the first detection of spores, as well as the date with maximum of spores, shifted from 270 to 248 DOY, and from 315 to 265 DOY, respectively. The acceleration of the former parameter by 22 days and the latter by 50 days has great influence on the severity of stem canker of oilseed rape.  相似文献   
996.
Iron is required for the Fe-S cluster assembly which occurs in chloroplasts, mitochondria, and cytosol and here we characterized 44 Fe-S cluster biosynthesis genes and investigated their expression profiles during different peach flowering stages. Quantitative real-time PCR analysis shows that the highest expression of most peach Fe-S cluster biosynthesis genes appeared in the full bloom stage. Also, the highest Fe accumulation occurred in the full bloom stage followed by beginning bloom, petal fall, and bud swell stages. Activities of nitrite reductase (NiR) and succinate dehydrogenase (SDH) were closely correlated to the flower Fe content, whereas the aconitase (ACO) activity kept steady during the whole flowering process. Moreover, shading treatment significantly reduced Fe accumulation and NiR, SDH, and ACO activities of the full blooming flowers. Seventeen Fe-S cluster biosynthesis genes were down-regulated in response to a shading treatment. In particular, plastid sulfur mobilization genes were sensitive to the shading treatment.  相似文献   
997.
998.
Previous studies have demonstrated that the c-Jun N-terminal kinase (JNK) pathway plays an important role in inducing neuronal apoptosis following cerebral ischemic injury. JNK signaling pathway in activated during cerebral ischemic injury. It participates in ischemia-induced neuronal apoptosis. However, whether JNK signaling is involved in the process of neuronal apoptosis of diabetes-induced cerebral ischemia is largely unknown. This study was undertaken to evaluate the influence of cerebral ischemia–reperfusion injury on phosphorylation of JNK in diabetic rats. Twenty-four adult streptozotocin induced diabetic and 24 adult non-diabetic rats were randomly subjected to 15 min of forebrain ischemia followed by reperfusion for 0, 1, 3, and 6 h. Sixteen sham-operated diabetic and non-diabetic rats were used as controls. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL). Protein expression of phospho-JNK was examined by immunohistochemistry and Western blot. The numbers of TUNEL-positive cells and phospho-JNK protein expression in the cerebral cortices after 1, 3 and 6 h reperfusion was significantly higher in diabetic rats compared to non-diabetic animals subjected to ischemia and reperfusion (p < 0.05). Western blot analysis showed significantly higher phospho-JNK protein expression in the cerebral cortices of the diabetic rats after 1 and 3 h reperfusion than that was presented in non-diabetic animals subjected to ischemia and reperfusion (p < 0.05). These findings suggest that increased phosphorylation of JNK may be associated with diabetes-enhanced ischemic brain damage.  相似文献   
999.
In this study, late Holocene vegetation, climate and human impacts were investigated using multiproxy data-pollen percentages, pollen accumulation rates (PAR), humification and loss-on-ignition (LOI)—measured from peat sediments from Daiyun Mountain, southeast China. A stratigraphic chronology was established on the basis of four radiocarbon dates. The 4,350 year sequence of vegetation history and climate change exhibits three distinctive stages: (1) 4,350–1,000 cal bp, during which the vegetation was dominated by evergreen forests mainly composed of broad-leaf trees, indicating a warm and wet climate; (2) 1,000–550 cal bp, during which the climate was thought to be cool and dry, based on a decrease in pollen percentages and the PARs of trees, shrubs and wetland herbs, and an increase in the pollen percentage and PAR of dry land herbs, as well as high overall LOI values; and (3) 550 cal bp to modern times, during which higher pollen percentages of dry land and wetland herbs, along with low pollen percentage and PAR of trees and shrubs, as well as low absorbance and LOI values, suggest relatively cooler but wetter climate conditions. In addition, major climatic events, such as the warm period from ad 670–960, the Medieval Warm Period (ad 1050–1520) and the Little Ice Age (ad 1580–1850), could be identified within the peat sediments in this study, with climatic conditions at these times being characteristically warm and wet, warm and dry, and cold and wet, respectively. Pollen signals indicate significant human impact since 1,000 cal bp, which may be linked to the development of the local porcelain industry and a rapid increase in the population in the study region.  相似文献   
1000.
正Several recent studies in Virologica Sinica and other journals have highlighted the enormous international challenge of emerging arboviral diseases,such as Zika virus disease,dengue,and chikungunya(Islam et al.,2015;Maurice et al.,2015;Dai et al.,2016;Deng et al.,2016;Song et al.,2016;Wang et al.,2016;Xu et al.,2016;Zhang et al.,2016;Zhou et  相似文献   
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