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1.
针对风电机组偏航系统具有高度非线性与不确定性的特性,提出基于生物神经内分泌免疫调节机制的仿生偏航控制方法。设计了一种仿生偏航控制器,其中偏差处理模块根据免疫机制对偏差进行动态处理,偏差控制模块通过调整"抗体"的数量来消除控制偏差,主控模块调整偏差处理和偏差控制模块的控制作用,优化模块与辨识模块用于优化偏差处理和偏差控制模块的参数,保证偏航系统的自学习和自适应能力。仿真实验结果表明:该控制方法具有较好的控制性能。  相似文献   

2.
应用基因重组肝细胞生长因子(HGF)可诱导入肺癌细胞运动和侵袭,通过细胞离散,集落扩散和基底膜侵袭实验证明,侵袭抑制因子-2(IIF-2)可明显地抑制由HGF诱导的作用,该抑制作用可被抗IIF-2抗体所阻断,表明IIF-2在肿瘤转移的预防和治疗方面可能具有重要意义。  相似文献   

3.
将大鼠肝细胞接种至2种不同微载体(实体微载体Cytodex、多孔微载体Cytopore)进行微重力高密度体外培养,观察细胞生长形态及细胞活力等情况,并通过细胞代谢功能指标葡萄糖、白蛋白、尿素等指标的测定,反映细胞在两种载体的生长和代谢情况。结果表明,Cytopore的MTT值、代谢指标值是Cytodex的1倍左右。因此,大鼠肝细胞在载体Cytopore的高密度培养比载体Cytodex更有利于细胞的生长增殖和代谢。  相似文献   

4.
将大鼠肝细胞接种至2种不同微载体(实体微载体Cytodex、多孔微载体Cytopore)进行微重力高密度体外培养,观察细胞生长形态及细胞活力等情况,并通过细胞代谢功能指标葡萄糖、白蛋白、尿素等指标的测定,反映细胞在两种载体的生长和代谢情况。结果表明,Cytopore的MTT值、代谢指标值是Cytodex的1倍左右。因此,大鼠肝细胞在载体Cytopore的高密度培养比载体Cytodex更有利于细胞的生长增殖和代谢。  相似文献   

5.
目的探讨短暂前脑缺血再灌注(transient forebrain ischemia-reperfusion,I/R)对脑源性神经营养因子(brainderived neurotrophic factor,BDNF)蛋白及mRNA表达的影响,为进一步探索大鼠海马CA1区神经元损伤机制提供新的思路。方法将雄性SD大鼠随机分为control组、sham组和I/R组,利用Western blot和荧光定量PCR分析I/R后大鼠BDNF蛋白及mRNA表达的变化;染色质免疫共沉淀(chromatin immunoprecipitation,ChIP)试验检测I/R后大鼠BDNF基因启动子上H3K27的乙酰化水平。结果与control组相比,sham组大鼠CA1和CA3区BDNF蛋白和m RNA表达差异无统计学意义(P> 0. 05)。与sham组相比,I/R组大鼠CA1区BDNF蛋白表达显著下降(P <0. 001),而CA3区BDNF蛋白表达增高(P <0. 05);I/R组大鼠CA1区BDNF mRNAⅠ、Ⅱ和Ⅵ的表达均显著增高(P <0. 01),而mRNAⅣ的表达...  相似文献   

6.
目的原核表达并纯化仅含BH3结构域的细胞凋亡调控蛋白BMF,并进行CyclinA-Cdk2特异性底物的体外磷酸化检测。方法从HeLa细胞中扩增人源BMF基因,克隆至pGEX-6P-1表达载体,转化大肠杆菌BL21(DE3),IPTG诱导表达,表达产物经Glutathione Sepharose 4B凝胶柱亲和层析纯化。以纯化的融合蛋白GST-BMF作为底物,免疫共沉淀得到的CyclinA-Cdk2作为酶源,并以Cdk2的已知底物HistoneH1作为阳性对照,进行体外磷酸化试验。结果BMF基因的原核表达载体构建正确,表达的融合蛋白GST-BMF约占菌体总蛋白的40%,纯化后纯度约为90%。在体外磷酸化试验中,未出现与目的蛋白GST-BMF相对分子质量相近的放射自显影带。结论BMF蛋白在无细胞体系中不能被CyclinA-Cdk2磷酸化。  相似文献   

7.
目的检测不同浓度β-羟丁酸(β-hydroxy butyrate,BHBA)对体外培养牛肝细胞肉碱脂酰基转移酶Ⅰ(Carnitine palmityl transferase-Ⅰ,CPT-Ⅰ)转录及翻译水平的影响。方法分别采用荧光定量PCR法和ELISA法,检测不同浓度BHBA(0、0.3、0.6、1.2、2.4、4.8mmol/L)对体外培养牛肝细胞CPT-I基因和蛋白表达的影响。结果随着BHBA浓度的增加,肝细胞CPT-Ⅰ的转录和翻译水平均下降。当BHBA浓度大于1.2mmol/L时,肝细胞CPT-I的转录和翻译水平下降更显著。结论高浓度的BHBA可显著抑制体外培养牛肝细胞CPT-I的表达,可能减少肝细胞脂肪酸氧化代谢。  相似文献   

8.
目的纯化重组人睫状神经营养因子(rhCNTF)。方法破菌液上清经硫酸铵分级沉淀和G-25脱盐后,用QSepharose FF阴离子交换层析初纯,再经Superdex 75 prepgrade凝胶过滤精制,并对纯化产物进行各项检测。结果纯化的rhC-NTF纯度达95%以上,蛋白浓度约为2mg/ml,收率约30%,相对分子质量21600,等电点为6.15,与理论值相符合。Western blot检测证明纯化蛋白能够与特异性抗体结合,并能够明显刺激鸡胚背根神经节突触生长。结论采用盐析、离子交换、凝胶过滤等方法有机组合,成功分离纯化了rhCNTF蛋白。  相似文献   

9.
葛君  王栋 《辽宁化工》2006,35(9):497-499,502
研究以酸性类染料酸性红B模拟废水为对象,通过循环伏安法与整体电解获得其电化学反应特性,通过调控溶液的性质考察了不同电解质体系对其降解效果的影响。实验结果表明,通过对液相组分的调控,能产生加速电化学反应,较彻底降解底物的效果。为电化学法处理难降解有机污染物的技术改善提供参考。  相似文献   

10.
目的 研究聚乙二醇(PEG)修饰的重组人睫状神经营养因子(recombinant human ciliary neurotrophic factor,rhCNTF)对ob/ob小鼠非酒精性脂肪肝(non-alcoholic fatty liver disease,NAFLD)的治疗作用,为PEG-rhCNTF的临床应用提供参考。方法 以14只4~10周龄雌性野生型C57BL/6J小鼠为正常对照组,83只4~10周龄雌性ob/ob小鼠分为赋形剂组、利拉鲁肽0.1 mg/kg组(每天给药2次)和0.2 mg/kg组(每4 d给药1次)、rhCNTF 0.1 mg/kg组(每天给药1次)以及PEG-rhCNTF 0.05、0.1和0.2 mg/kg组(每4 d给药1次),每组11~12只,均经皮下注射给药。给药期间测定小鼠体质量、24 h饲料消耗量、连续血糖和随机血糖水平及口服葡萄糖耐量;实验终点时,先测定小鼠空腹血糖水平,再测定空腹血清胰岛素(fasting serum insulin,FINS)水平,并计算胰岛素抵抗指数(homeostasis model assessment of i...  相似文献   

11.
The distinct effects of the estrogen and progestin components of hormonal therapy on the metabolism of apolipoprotein (apo) B‐containing lipoproteins have not been studied. We enrolled eight healthy postmenopausal women in a placebo‐controlled, randomized, double‐blind crossover study. Each subject received placebo, conjugated equine estrogen (CEE, 0.625 mg/day) and CEE plus medroxyprogesterone acetate (MPA, 2.5 mg/day) for 8 weeks in a randomized order, with a 4‐week washout between phases. Main outcomes were the fractional catabolic rate (FCR) and production rate (PR) of apo B100 in triglyceride‐rich lipoproteins (TRL), intermediate‐density lipoproteins (IDL) and low ‐density lipoprotein (LDL) and of apo B48 in TRL. Compared to placebo, CEE increased TRL apo B100 PR (p = 0.04). CEE also increased LDL apo B100 FCR (p = 0.02), but this effect was offset by a significant increase in LDL apo B100 PR (p = 0.04). Adding MPA to CEE negated the CEE effects resulting in no significant changes in TRL apo B100 PR and LDL apo B100 FCR and PR relative to placebo. Relative to placebo, during CEE there was a trend toward a reduction in plasma apo B48 concentrations and PR (p = 0.07 and p = 0.12, respectively). Compared with CEE, CEE + MPA significantly increased TRL apo B48 FCR (p = 0.02) as well as apo B48 PR (p = 0.01), resulting in no significant changes in apo B48 concentration. Estrogen and progestin have independent and opposing effects on the metabolism of the atherogenic apo B100‐ and apo B48‐containing lipoproteins.  相似文献   

12.
Oxidized LDL (oxLDL) has been shown to activate the sphingomyelinase pathway producing ceramide in vascular smooth muscle cells. Therefore ceramide, which is a biologically active lipid causing apoptosis in a variety of cells, may be involved in the apoptotic action of oxLDL. In this study, we examined whether cholesterol enriched diets affected ceramide metabolism and oxidation product of LDL, represented by degradation of apolipoprotein B-100 (apoB) in apoE-deficient (apoE−/−) mice. ApoE−/− and wild type mice were fed a standard (AIN-76) diet or 1% cholesterol-enriched diet for 8 weeks. Tissue ceramide levels were analyzed using electrospray tandem mass spectrometry (LC-MS/MS). Ceramide levels in the plasma and the liver of apoE−/− mice were intrinsically higher than those of the wild type. In apoE−/− mice, dietary cholesterol significantly increased several ceramides and degradation products of apoB in plasma compared to those fed the control diet. Dietary cholesterol did not affect tissue ceramide levels in the wild type mice. Based on these results, plasma ceramides possibly correlate with the increase in LDL oxidation and are a risk factor for atherosclerosis.  相似文献   

13.
The liver is vulnerable to oxidative attacks from heavy metals, such as iron, as well as some drugs, including acetaminophen. It has been shown that enhanced oxidative stress in the liver leads to excessive ROS production and mitochondrial dysfunction, resulting in organ injury. The beneficial effects of Spatholobi Caulis (SC), a natural herbal medicine, include treating ischemic stroke, inhibiting tumor cell invasion, pro-angiogenic activities, and anti-inflammatory properties. Scientific studies on its effects against hepatotoxic reagents (e.g., iron and acetaminophen), as well as their underlying mechanisms, are insufficient. This study examined the antioxidant effects and mechanisms of SC in vitro and in vivo. In cells, the proinflammatory mediator, arachidonic acid (AA), plus iron, significantly induced an increase in ROS generation, the damage in mitochondrial membrane potential, and the resulting apoptosis, which were markedly blocked by SC. More importantly, SC affected the activation of AMP-activated protein kinase (AMPK)-related proteins, which were vital to regulating oxidative stress in cells. In addition, SC mediated the expression of Yes-associated protein (YAP)-related proteins. Among the active compounds in SC, the procyanidin B2, but not liquiritigenin, daidzein, and genistein, significantly inhibited the cytotoxicity induced by AA + iron, and activated the LKB1-AMPK pathway. In mice, the oral administration of SC alleviated the elevations of ALT and histological changes by the acetaminophen-induced liver injury. These results reveal the potential of SC and a key bioactive component, procyanidin B2, as antioxidant candidates for hepatoprotection.  相似文献   

14.
Despite a wide range of bactericides and antiseptics, the treatment of chronic or complicated wounds is still a major challenge for modern medicine. Topical medications are the most sought-after new agents for use as treatment. The therapeutic concentration of their active substances is easy to achieve with the lowest possible burden on the patient’s body. This study assesses the effect of salvianolic acid B (Sal B) on the proliferation, migration, and production of collagen type III by fibroblasts, which are the most important processes in wound healing. The study was conducted on human gingival fibroblasts obtained from primary cell culture. The results showed that Sal B at a dose of 75 µg/mL increases the cell viability with significant stimulation of the cell migration as demonstrated in the wound healing assay, as well as an increase in the expression of collagen type III, which has great importance in the initial stages of wound scarring. The results obtained in the conducted studies and previous scientific reports on the antibacterial properties and low toxicity of Sal B indicate its high potential in wound healing.  相似文献   

15.
目的探讨尿S100B蛋白在新生儿缺氧缺血脑病早期诊断的临床价值。方法对窒息患儿以临床表现为基础,同时监测38例HIE患儿出生后3d内尿S100B蛋白(利用ELISA方法)的动态变化。结果HIE组尿S100B水平在生后3d比较有显著性差异(P<0.01),且尿S100B蛋白含量与HIE的临床分度成正比,尿S100B蛋白水平越高,脑损伤越严重,预后越差。结论S100B蛋白水平升高均提示HIE的发生,且能反映其严重程度。  相似文献   

16.
Chronic mild stress (CMS) affects the hippocampal structure and function in the rat. S100B, a calcium-binding protein secreted by astrocytes, has been shown to be increased in serum of patients with depression and associated with good therapeutic response and clinical outcome. This work aimed to study the impact of CMS and fluoxetine on depressive-like behaviors in rats, as well as the concomitant expression of the astroglial protein S100B and of its receptor RAGE (receptor for advanced glycation end products) in the hippocampus and Cerebrospinal fluid of the same group of animals. S100B and sRAGE (circulating soluble form of RAGE) were measured in CSF by ELISA, and S100B and RAGE were measured in hippocampal slices by Western blot. Our study has demonstrated that stress and depression decrease S100B and RAGE/SRAGE expression and antidepressant treatment reverses or blocks these effects. This result suggested that S100B/RAGE interactions may be involved in the development and maintenance of depression and may play an important role in the mechanism of antidepressants' therapeutic action.  相似文献   

17.
The emergence, survival, growth and maintenance of autoreactive (AR) B-cell clones, the hallmark of humoral autoimmunity, leave their footprints in B-cell receptor repertoires. Collecting IgH sequences related to polyreactive (PR) ones from adaptive immune receptor repertoire (AIRR) datasets make the reconstruction and analysis of PR/AR B-cell lineages possible. We developed a computational approach, named ImmChainTracer, to extract members and to visualize clonal relationships of such B-cell lineages. Our approach was successfully applied on the IgH repertoires of patients suffering from monogenic hypomorphic RAG1 and 2 deficiency (pRD) or polygenic systemic lupus erythematosus (SLE) autoimmune diseases to identify relatives of AR IgH sequences and to track their fate in AIRRs. Signs of clonal expansion, affinity maturation and class-switching events in PR/AR and non-PR/AR B-cell lineages were revealed. An extension of our method towards B-cell expansion caused by any trigger (e.g., infection, vaccination or antibody development) may provide deeper insight into antigen specific B-lymphogenesis.  相似文献   

18.
With the rapid growth of the wireless communication industry, humans are extensively exposed to electromagnetic fields (EMF) comprised of radiofrequency (RF). The skin is considered the primary target of EMFs given its outermost location. Recent evidence suggests that extremely low frequency (ELF)-EMF can improve the efficacy of DNA repair in human cell-lines. However, the effects of EMF-RF on DNA damage remain unknown. Here, we investigated the impact of EMF-long term evolution (LTE, 1.762 GHz, 8 W/kg) irradiation on DNA double-strand break (DSB) using the murine melanoma cell line B16 and the human keratinocyte cell line HaCaT. EMF-LTE exposure alone did not affect cell viability or induce apoptosis or necrosis. In addition, DNA DSB damage, as determined by the neutral comet assay, was not induced by EMF-LTE irradiation. Of note, EMF-LTE exposure can attenuate the DNA DSB damage induced by physical and chemical DNA damaging agents (such as ionizing radiation (IR, 10 Gy) in HaCaT and B16 cells and bleomycin (BLM, 3 μM) in HaCaT cells and a human melanoma cell line MNT-1), suggesting that EMF-LTE promotes the repair of DNA DSB damage. The protective effect of EMF-LTE against DNA damage was further confirmed by attenuation of the DNA damage marker γ-H2AX after exposure to EMF-LTE in HaCaT and B16 cells. Most importantly, irradiation of EMF-LTE (1.76 GHz, 6 W/kg, 8 h/day) on mice in vivo for 4 weeks reduced the γ-H2AX level in the skin tissue, further supporting the protective effects of EMF-LTE against DNA DSB damage. Furthermore, p53, the master tumor-suppressor gene, was commonly upregulated by EMF-LTE irradiation in B16 and HaCaT cells. This finding suggests that p53 plays a role in the protective effect of EMF-LTE against DNA DSBs. Collectively, these results demonstrated that EMF-LTE might have a protective effect against DNA DSB damage in the skin, although further studies are necessary to understand its impact on human health.  相似文献   

19.
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