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31.
陶晓璇  郑志兵  陈伟  李松 《化学试剂》2012,34(7):581-584
以5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基-1H-吡唑-3-甲酸与二氯亚砜为起始原料,经酰氯化反应、酰胺反应、霍夫曼重排以及水解反应生成中间体5-(4-氯苯基)-1-(2,4-二氯苯基)-3-氨基-4-甲基-1H-吡唑,再经过与氯甲酸苯酯反应、胺酯交换反应得到标题化合物,其结构经1HNMR、MS谱确证,总收率26.9%。  相似文献   
32.
以4-(4-哌啶基)-1-氯丁烷、L-酪氨酸等为原料经过7步反应得到盐酸替罗非班。此合成路线操作简易,总收率达21.6%,中间体及最终产物结构均经过MS和1H NMR确证。  相似文献   
33.
二磺酰胺类内皮素受体拮抗剂的构效关系研究   总被引:2,自引:0,他引:2  
应用量子化学方法计算了34个二磺酰胺类化合物的结构参数,并用BP神经网络对34个二磺酰胺类化合物的结构参数与ETs受体拮抗活性进行了定量构效关系分析,获得了一个预测能力较好的QSAR神经网络模型。研究表明:二磺酰胺类化合物与ETs受体之间存在直接的电荷迁移作用,电子结构、疏水性是影响其活性的主要因素。本文建立的二磺酰胺类化合物分子结构与ETs受体拮抗活性之间的定量构效关系,为设计合成新的此类内皮素受体拮抗剂提供了参考。  相似文献   
34.
Neurofibromatosis type 1 (NF1) is a common inherited disorder caused by mutations of the NF1 gene that encodes the Ras-GTPase activating protein neurofibromin, leading to overactivation of Ras-dependent signaling pathways such as the mTOR pathway. It is often characterized by a broad range of cognitive symptoms that are currently untreated. The serotonin 5-HT6 receptor is a potentially relevant target in view of its ability to associate with neurofibromin and to engage the mTOR pathway to compromise cognition in several cognitive impairment paradigms. Here, we show that constitutively active 5-HT6 receptors contribute to increased mTOR activity in the brain of Nf1+/− mice, a preclinical model recapitulating some behavioral alterations of NF1. Correspondingly, peripheral administration of SB258585, a 5-HT6 receptor inverse agonist, or rapamycin, abolished deficits in long-term social and associative memories in Nf1+/− mice, whereas administration of CPPQ, a neutral antagonist, did not produce cognitive improvement. These results show a key influence of mTOR activation by constitutively active 5-HT6 receptors in NF1 cognitive symptoms. They provide a proof of concept that 5-HT6 receptor inverse agonists already in clinical development as symptomatic treatments to reduce cognitive decline in dementia and psychoses, might be repurposed as therapies alleviating cognitive deficits in NF1 patients.  相似文献   
35.
Mineralocorticoid receptor antagonists (MRA) are drugs with a potentially broad spectrum of action. They have been reported to have healing effects in many diseases, such as chronic heart failure, hypertension, or nephrotic syndrome. Numerous studies suggest that mineralocorticoid receptor activation is pathogenic and a progression factor of chronic kidney disease (CKD); however, results of studies on the use of MRA in the treatment of CKD are inconclusive. Current guidelines recommend against the use of MRA in patients with advanced CKD. Although, there is growing interest on their use in this population due to treatment benefits. In this review, we summarize studies which were purposed to evaluate the impact of MRA therapy on CKD patients. Despite many benefits of this treatment e.g., reducing cardiovascular mortality or alleviating proteinuria, steroidal MRA (such as spironolactone or eplerenone) have a low safety profile. They often lead to hyperkalemia complications which are dangerous in patients with CKD, and diabetic nephropathy, especially in hemodialysis patients. Studies on recently developed nonsteroidal MRA showed that they have fewer side effects. In our review, we discuss steroidal and nonsteroidal MRA treatment effects on the estimated glomerular filtration rate (eGFR), proteinuria, the cardiovascular system, and hyperkalemia in CKD patients. We present new content and recent publications in this field.  相似文献   
36.
杜荣辉  管立  戴德哉  张媛  吉民 《金属学报》2004,9(12):1357-1360
目的: 建立内皮素受体拮抗剂CPU-0213 在小鼠和大鼠血清中的检测方法, 测定单次静脉注射(iv) CPU-0213 80 mg·kg-1后在小鼠和大鼠体内的药代动力学。方法: 用HPLC 测定小鼠和大鼠血清中的药物浓度, 3P97 程序拟合药动学参数。结果: CPU-0213 在0.4~200 μg·L-1的范围内呈良好的线性关系(r=0.9998), 最低检测浓度为35 μg·L-1。日内差小于2.7 %, 日间差小于6.3 %, 方法回收率大于95.9 %。CPU-0213 在小鼠和大鼠体内的药-时数据均符合二室模型, 消除半衰期分别为83.0±1.8 min 和96.6±11.5 min 。结论: 该方法灵敏、简单, 专属性强, 重现性好。单次iv CPU-021380 mg·kg-1后, 在小鼠和大鼠体内的药代动力学未见种属差异性。  相似文献   
37.
Fungal diseases result in significant losses of fruits and vegetables during handling, transportation and storage. At present, post-production fungal spoilage is predominantly controlled by using synthetic fungicides. Under the global climate change scenario and with the need for sustainable agriculture, biological control methods of fungal diseases, using antagonistic microorganisms, are emerging as ecofriendly alternatives to the use of fungicides. The potential of microbial antagonists, isolated from a diversity of natural habitats, for postharvest disease suppression has been investigated. Postharvest biocontrol systems involve tripartite interaction between microbial antagonists, the pathogen and the host, affected by environmental conditions. Several modes for fungistatic activities of microbial antagonists have been suggested, including competition for nutrients and space, mycoparasitism, secretion of antifungal antibiotics and volatile metabolites and induction of host resistance. Postharvest application of microbial antagonists is more successful for efficient disease control in comparison to pre-harvest application. Attempts have also been made to improve the overall efficacy of antagonists by combining them with different physical and chemical substances and methods. Globally, many microbe-based biocontrol products have been developed and registered for commercial use. The present review provides a brief overview on the use of microbial antagonists as postharvest biocontrol agents and summarises information on their isolation, mechanisms of action, application methods, efficacy enhancement, product formulation and commercialisation.  相似文献   
38.
蒜苔采后灰霉病害及生防拮抗菌的筛选研究   总被引:1,自引:0,他引:1  
薛婷  李喜宏  陈丽  马骏 《食品科学》2006,27(6):220-222
在蒜苔贮藏后期,从0℃冷库里发生灰霉病的蒜苔上分离到灰霉菌,经纯化和致病性鉴定得到灰霉属病原菌株。并且在其中并未发病的蒜苔分离到16种拮抗细菌,通过平板筛选法筛选出4株对灰霉菌具有拮抗作用的细菌,这4株拮抗菌在平板上对灰霉病菌的抑制力分别为:63.5%、47.6%、41.3%、38.1%。  相似文献   
39.
为分离筛选对烟草赤星病有良好防效的拮抗菌,以烟草赤星病链格孢菌为靶菌,从蚯蚓粪中经初筛和复筛获得拮抗菌,通过形态、生理生化特征和16S rDNA分析鉴定拮抗菌种类,并对烟草赤星病的防治效果进行了研究。结果表明,筛选出一株拮抗菌Q96,初筛和复筛的抑菌率均超过60%,经鉴定为副地衣芽孢杆菌(Bacillus paralicheniformis),其活菌液(稀释10倍)对孢子萌发和菌丝生长的抑制率分别为73.33%和79.68%,粗发酵液离体防效可达60.04%。Q96菌株可作为抗烟草赤星病生防菌剂的菌种资源。  相似文献   
40.
Increasing evidence links the RAGE (receptor for advanced glycation end products)/DIAPH1 (Diaphanous 1) signaling axis to the pathogenesis of diabetic complications. RAGE is a multi-ligand receptor and through these ligand–receptor interactions, extensive maladaptive effects are exerted on cell types and tissues targeted for dysfunction in hyperglycemia observed in both type 1 and type 2 diabetes. Recent evidence indicates that RAGE ligands, acting as damage-associated molecular patterns molecules, or DAMPs, through RAGE may impact interferon signaling pathways, specifically through upregulation of IRF7 (interferon regulatory factor 7), thereby heralding and evoking pro-inflammatory effects on vulnerable tissues. Although successful targeting of RAGE in the clinical milieu has, to date, not been met with success, recent approaches to target RAGE intracellular signaling may hold promise to fill this critical gap. This review focuses on recent examples of highlights and updates to the pathobiology of RAGE and DIAPH1 in diabetic complications.  相似文献   
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