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81.
A novel operation strategy employing self-generated oscillation to imrpove the performances of bioreactors is proposed and applied to a model system consisting of two continuous stirredtank bioreators (CSTBs) connected in series. It is demonstrated via computation that the performance of the system (in terms of timeaveraged cell concentration) can be greatly enhanced by adopting the proposed strategy. The process concept presented and the results obtained in this paper are expected to have significant implications beyond the bioprocessing industry.  相似文献   
82.
Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial lung disease that seriously threatens the health of patients. The pathogenesis of IPF is still unclear, and there is a lack of effective therapeutic drugs. Myofibroblasts are the main effector cells of IPF, leading to excessive deposition of extracellular matrix (ECM) and promoting the progression of fibrosis. Inhibiting the excessive activation and relieving autophagy blockage of myofibroblasts is the key to treat IPF. PI3K/Akt/mTOR pathway plays a key regulatory role in promoting fibroblast activation and autophagy inhibition in lung fibrosis. Duvelisib is a PI3K inhibitor that can simultaneously inhibit the activities of PI3K-δ and PI3K-γ, and is mainly used for the treatment of relapsed/refractory chronic lymphocytic leukaemia (CLL) and small lymphocytic lymphoma tumour (SLL). In this study, we aimed to examine the effects of Duvelisib on pulmonary fibrosis. We used a mouse model of bleomycin-induced pulmonary fibrosis to evaluate the effects of Duvelisib on pulmonary fibrosis in vivo and further explored the potential pharmacological mechanisms of Duvelisib in lung fibroblasts in vitro. The in vivo experiments showed that Duvelisib significantly alleviated bleomycin-induced collagen deposition and improved pulmonary function. In vitro and in vivo pharmacological experiments showed that Duvelisib dose-dependently suppressed lung fibroblast activation and improved autophagy inhibition by inhibiting the phosphorylation of PI3K, Akt and mTOR. Our results indicate that Duvelisib can alleviate the severity of pulmonary fibrosis and provide potential drugs for the treatment of pulmonary fibrosis.  相似文献   
83.
Summary Xanthan fermentations in W/O dispersions performed better than the control in both small flasks and a 6.6-L fermentor. The better bulk mixing and oxygen transfer achieved in the dispersion resulted in a still rising xanthan concentration of 65 g/L, compared with 26 g/L in the control. A phase inversion phenomenon was observed when n-hexadecane recovered from previous runs was used as the oil.  相似文献   
84.
85.
吉林省满族体质特征调查   总被引:8,自引:2,他引:6  
  相似文献   
86.
乌云伞的解剖学及花粉形态学研究   总被引:3,自引:0,他引:3  
八角莲属(Dysosma)是小檗科(Berberidaceae)一个重要属,全国共有7个种,大约分布于北纬23—32°,东经94—122°之间。湖北八角莲属有4个种,其中乌云伞(Dysosma lichuanensis Z. Cheng, sp. nev., ined.)为内定种,是多年生草本,它的形态特征与八角莲(Dysosma  相似文献   
87.
研究了伴刀豆球蛋白A(ConA)和层粘连蛋白(LN)与巨噬细胞膜受体竞争结合,初步推测两个配体与同一膜受体结合的可能性.结果表明,LN可以竞争抑制FTTC-ConA与巨噬细胞膜受体的结合,说明ConA和LN两种配体各自的巨噬细胞膜受体中有部分可能是共同的,而加入ConA反而增加巨噬细胞膜上结合的FITC-LN量,这可能是因为ConA和LN的分子特性导致的.  相似文献   
88.
89.
Clathrin-mediated endocytosis (CME) is the major endocytic pathway in eukaryotic cells that directly regulates abundance of plasma membrane proteins. Clathrin triskelia are composed of clathrin heavy chains (CHCs) and light chains (CLCs), and the phytohormone auxin differentially regulates membrane-associated CLCs and CHCs, modulating the endocytosis and therefore the distribution of auxin efflux transporter PIN-FORMED2 (PIN2). However, the molecular mechanisms by which auxin regulates clathrin are still poorly understood. Transmembrane kinase (TMKs) family proteins are considered to contribute to auxin signaling and plant development; it remains unclear whether they are involved in PIN transport by CME. We assessed TMKs involvement in the regulation of clathrin by auxin, using genetic, pharmacological, and cytological approaches including live-cell imaging and immunofluorescence. In tmk1 mutant seedlings, auxin failed to rapidly regulate abundance of both CHC and CLC and to inhibit PIN2 endocytosis, leading to an impaired asymmetric distribution of PIN2 and therefore auxin. Furthermore, TMK3 and TMK4 were shown not to be involved in regulation of clathrin by auxin. In summary, TMK1 is essential for auxin-regulated clathrin recruitment and CME. TMK1 therefore plays a critical role in the establishment of an asymmetric distribution of PIN2 and an auxin gradient during root gravitropism.  相似文献   
90.
The silkworm Bombyx mori L. is a model organism of the order Lepidoptera. Understanding the mechanism of pesticide resistance in silkworms is valuable for Lepidopteran pest control. In this study, comparative metabolomics was used to analyze the metabolites of 2 silkworm strains with different pesticide resistance levels at 6, 12, and 24 h after feeding with fenpropathrin. Twenty-six of 27 metabolites showed significant differences after fenpropathrin treatment and were classified into 6 metabolic pathways: glycerophospholipid metabolism, sulfur metabolism, glycolysis, amino acid metabolism, the urea cycle, and the tricarboxylic acid (TCA) cycle. After analyzing the percentage changes in the metabolic pathways at the 3 time points, sulfur metabolism, glycolysis, and the TCA cycle showed significant responses to fenpropathrin. Confirmatory experiments were performed by feeding silkworms with key metabolites of the 3 pathways. The combination of iron(II) fumarate + folic acid (IF-FA) enhanced fenpropathrin resistance in silkworms 6.38 fold, indicating that the TCA cycle is the core pathway associated with resistance. Furthermore, the disruption of several energy-related metabolic pathways caused by fenpropathrin was shown to be recovered by IF-FA in vitro. Therefore, IF-FA may have a role in boosting silkworm pesticide resistance by modulating the equilibrium between the TCA cycle and its related metabolic pathways.  相似文献   
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