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61.
研制广谱抗病毒制剂是病毒学前瞻性方向,也是国际医药界倍受瞩目的热点之一.近年来,广谱抗病毒制剂相关研究获得长足进展,突破了抗病毒制剂单一宿主的瓶颈与限制,以及广谱类制剂活性相对较弱的原有思维,部分成果已面向临床应用.本文基于病毒侵染以及宿主细胞防御两个层面,全面综述新型广谱抗病毒抑制剂的研究进展与应用潜力,讨论现存的挑战,并展望了未来研究趋势.  相似文献   
62.
The mutagenic activities of quinoline, isoquinoline, phenanthridine, benzo(f)quinoline, benzo(h)quinoline and their α-amino derivatives were compared in relation to the effect of structural changes using the Salmonella typhimurium test system. All mutagenic compounds tested require the liver microsomal fraction for their mutagenic activity. Phenanthridine, two benzoquinolines and quinoline were mutagenic. α-Amination of two benzoquinolines and quinoline resulted to increase their mutagenic activity intensively. Addition of a benzene ring to the benzene moiety of 2-aminoquinoline, so that two carbon atoms are shared, affected distinctly the increase in the mutagenic activity. The co-existence of benzoquinoline series with 2-aminobenzo(f)quinoline showed the clear synergistic action.  相似文献   
63.
The textures of cooked rice prepared from aged rice grains and their improvement by reducing agents were investigated. For aged rice that was stored for 5 months without air by the operation of a vacuum packing machine, the stickiness/hardness ratio of cooked rice was as low as that of aged rice stored in air. The results of electrophoresis showed that oxidation of proteins in the former was advanced to the same degree as in the latter. The stickiness/hardness ratios of the aged rice were increased by the addition of sodium sulfite, cysteine, and dithiothreitol to the cooking water. Sodium sulfite, cysteine, and dithiothreitol cleave disulfide bonds to sulfhydryl groups. Therefore, cleaving disulfide bonds to sulfhydryl groups improved the texture. The addition of them to the cooking water also increased the extractable solids at the time of heating. Hence cleaving disulfide bonds to sulfhydryl groups must increase extractable solids. Consequently, the gelatinized paste layer thickened and the thick paste layer softened the cooked rice.  相似文献   
64.
对2012 年全球上市新药的基本信息,包括通用名、商品名、结构式、CAS 号、研发公司、上市国家和主要适应证进行汇总,为新药研发工作者提供参考。  相似文献   
65.
The use of Micro-Computed Tomography (MicroCT) for in vivo studies of small animals as models of human disease has risen tremendously due to the fact that MicroCT provides quantitative high-resolution three-dimensional (3D) anatomical data non-destructively and longitudinally. Most importantly, with the development of a novel preclinical iodinated contrast agent called eXIA160, functional and metabolic assessment of the heart became possible. However, prior to the advent of commercial MicroCT scanners equipped with X-ray flat-panel detector technology and easy-to-use cardio-respiratory gating, preclinical studies of cardiovascular disease (CVD) in small animals required a MicroCT technologist with advanced skills, and thus were impractical for widespread implementation. The goal of this work is to provide a practical guide to the use of the high-speed Quantum FX MicroCT system for comprehensive determination of myocardial global and regional function along with assessment of myocardial perfusion, metabolism and viability in healthy mice and in a cardiac ischemia mouse model induced by permanent occlusion of the left anterior descending coronary artery (LAD).  相似文献   
66.
Fibrinolysis is a process responsible for the dissolution of formed thrombi to re‐establish blood flow after thrombus formation. Plasminogen activator inhibitor‐1 (PAI‐1) inhibits urokinase‐type and tissue‐type plasminogen activator (uPA and tPA) and is the major negative regulator of fibrinolysis. Inhibition of PAI‐1 activity prevents thrombosis and accelerates fibrinolysis. However, a specific antagonist of PAI‐1 is currently unavailable for therapeutic use. We screened a panel of uPA variants with mutations at and near the active site to maximize their binding to PAI‐1 and identified a potent PAI‐1 antagonist, PAItrap. PAItrap is the serine protease domain of urokinase containing active‐site mutation (S195A) and four additional mutations (G37bR–R217L–C122A–N145Q). PAItrap inhibits human recombinant PAI‐1 with high potency (Kd = 0.15 nM) and high specificity. In vitro using human plasma, PAItrap showed significant thrombolytic activity by inhibiting endogenous PAI‐1. In addition, PAItrap inhibits both human and murine PAI‐1, allowing the evaluation in murine models. In vivo, using a laser‐induced thrombosis mouse model in which thrombus formation and fibrinolysis are monitored by intravital microscopy, PAItrap reduced fibrin generation and inhibited platelet accumulation following vascular injury. Therefore, this work demonstrates the feasibility to generate PAI‐1 inhibitors using inactivated urokinase.  相似文献   
67.
Ferulic acid (FA) has been reported to exhibit protective effects against amyloid-β (Aβ)-induced neurodegeneration in vitro and in vivo. Recently, we developed two water-soluble FA derivatives: 1-feruloyl glycerol and 1-feruloyl diglycerol. In this study, we examined the neuroprotective effects of these water-soluble FA derivatives on Aβ-induced neurodegeneration both in vitro and in vivo. FA and water-soluble FA derivatives inhibited Aβ aggregation and destabilized pre-aggregated Aβ to a similar extent. Furthermore, water-soluble FA derivatives, as well as FA, inhibited Aβ-induced neuronal cell death in cultured neuronal cells. In in vivo experiments, oral administration of water-soluble FA derivatives to mice improved Aβ-induced dysmnesia assessed by contextual fear conditioning test and protected hippocampal neurons against Aβ-induced neurotoxicity. This study provides useful evidence suggesting that water-soluble FA derivatives are expected to be effective neuroprotective agents.  相似文献   
68.
The plasmid encoding His-tagged organophosphorus hydrolase (OPH) cloned from Sphingobium fuliginis was modified to be transferred back to this bacterium. The replication function of S. amiense plasmid was inserted at downstream of OPH gene, and S. fuliginis was transformed with this plasmid. The transformant produced larger amount of active OPH with His-tag than E. coli.  相似文献   
69.
Enterovirus 71 (EV71) is a kind of RNA virus and one of the two causes of Hand, foot and mouth disease (HFMD). Inhibitors that target key components of Ras/Raf/MEK/ERK pathway in host cells could impair replication of EV71. A series of 3-benzyl-1,3-benzoxazine-2,4-diones were designed from a specific MEK inhibitor G8935, by replacing the double bond between C3 and C4 within the coumarin scaffold with amide bond. One compound (9f) showed submicromolar inhibitory activity among the 12 derivatives. Further optimization on 9f led to two active compounds (9k and 9m) with nanomolar bioactivities (55 nM and 60 nM). The results of enzymatic assays also demonstrated that this series of compounds were allosteric inhibitors of unphosphorylated MEK1. The binding mode of compound 9k was predicted by molecular dynamic simulation and the key interactions were same as published MEK1/2 allosteric inhibitors. In the cell-based assays, compounds 9k and 9m could effectively suppress the ERK1/2 pathway, expression of EV71 VP1, and EV71 induced cytopathic effect (CPE) in rhabdomyosarcoma (RD) cells.  相似文献   
70.
耿天龙  李佛生  于敏  罗枫雪  唐琳  王胜华 《广西植物》2016,36(10):1238-1244
该研究以金发草愈伤组织为材料,通过分析比较不同抗生素种类(卡那霉素、潮霉素、头孢噻呋钠和氨苄青霉素)和浓度对金发草愈伤组织生长分化的影响,来确定适用于金发草遗传转化体系中的抗性筛选剂和抑菌剂。结果表明:(1)金发草愈伤组织对卡那霉素很敏感,且其分化率随着卡那霉素浓度的增加显著减少( P=0.01)。当卡那霉素浓度为10 mg·L-1时,金发草愈伤组织的生长分化受到明显抑制,且有大量的白化苗形成,但分化率仍有36.56%;当卡那霉素浓度为15 mg·L-1时,金发草愈伤组织的分化率为11.94%,只有很少部分的愈伤分化出绿色的丛生苗;当卡那霉素浓度为20 mg·L-1时,金发草愈伤组织基本褐化死亡,分化率仅为2.26%。因此,浓度为15 mg·L-1的卡那霉素适合作为金发草遗传转化体系中的抗性筛选剂。(2)金发草愈伤组织对潮霉素的敏感性要比卡那霉素弱,且潮霉素对金发草愈伤组织分化率的影响小,但毒害作用大。因此,潮霉素不适合作为金发草遗传转化体系中的抗性筛选剂。(3)300 mg·L-1的头孢霉素和氨苄青霉素对金发草愈伤组织生长分化影响很小且能有效抑制杂菌的生长,较高浓度的氨苄青霉素对金发草愈伤组织的抑制作用不太明显。因此,300 mg·L-1的头孢霉素和较高浓度的氨苄青霉素均可作为金发草遗传转化体系中的抑菌剂。该研究确定了适用于农杆菌介导的金发草遗传转化体系中的抗性筛选剂和抑菌剂,为金发草的遗传改良及功能性基因的研究奠定了基础。  相似文献   
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