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161.
162.
The design, synthesis, and SAR of a series of retro bis-aminopyrrolidine ureas are described. Compounds from this series exhibited considerable binding affinity (Ki = 1 nM) and functional activity at MCH-R1, acceptable CYP2D6 inhibition, and good rat brain exposure.  相似文献   
163.
A series of benzamidines and benzamides was synthesized as selective inhibitors of vascular endothelial growth factor receptor (VEGFR) tyrosine kinases, and tested for inhibitory activity toward autophosphorylation by the enzyme assay. Selective inhibition of VEGFR-2 tyrosine kinase was observed in the salicylic amide 4e and the anthranilic amidine 5a, and their percent inhibitions of VEGFR-2 tyrosine kinase were 44-60% at a 10 microM concentration of compounds. The salicylic amide 4a showed inhibition of both VEGFR-1 and VEGFR-2 tyrosine kinases at a 10 microM concentration.  相似文献   
164.
1- 磷酸鞘氨醇是一种有生物活性的脂质代谢产物,具有调节细胞增殖、再生、迁移,细胞内钙离子移动,黏附分子表达以及激活单核细胞黏附内皮细胞等功效,在血管生理性再生及动脉粥样硬化斑块发生发展中发挥重要作用。1- 磷酸鞘氨醇在高密度脂蛋白中含量在所有脂蛋白中最高,其参与调节高密度脂蛋白的抗氧化、抗血栓、抗炎等效应,而这些反应与1- 磷酸鞘氨醇的生物学功能如血管发生、内皮保护、抑制平滑肌细胞迁移、心肌缺血再灌注损伤的保护等密切相关。对1- 磷酸鞘氨醇信号通路在心血管系统中的作用及以该通路为靶点的相关药物研究进展进行综述,为今后研究提供参考。  相似文献   
165.
166.

Background

The Supreme? laryngeal mask airway (SLMA) is a single-use LMA with double lumen design that allows separation of the respiratory and the alimentary tract, hence potentially reducing the gastric volume and risk of aspiration. The purpose of this prospective cohort study is to evaluate the the role of the SLMA as an airway technique for women undergoing category 2 and 3 Cesarean delivery under general anesthesia.

Methods

We recruited 584 parturients who underwent category 2 or 3 Cesarean delivery under general anesthesia, in which 193 parturients underwent category 2 and 391 parturients underwent category 3 Cesarean delivery. The primary outcome was insertion success rate at 1st attempt in SLMA insertion. The secondary outcomes included anaesthetic, obstetric outcomes and maternal side effects associated with airway device.

Results

The 1st attempt insertion success rate was 98.3%, while the overall insertion success rate was 100%. The mean (Standard deviation) time to effective ventilation was 15.6 (4.4) seconds. Orogastric tube insertion was successful at the 1st attempt in all parturients. There was no clinical evidence of aspiration or regurgitation. No episodes of hypoxemia, laryngospasm or bronchospasm were observed intra-operatively. The incidence of complications was low and with good maternal satisfaction reported.

Conclusions

The SLMA could be an alternative effective airway in category 2 and 3 parturients emergency Cesarean Delivery under general anesthesia in a carefully-selected obstetric population.

Trial registration

Clinical Trials Registration: Clinicaltrials.gov Registration NCT02026882. Registered on December 31, 2013.
  相似文献   
167.
Oleanolic acid (OA) is a natural cosmeceutical compound with various skin beneficial activities including inhibitory effect on hyaluronidase but the anti-hyaluronidase activity and mechanisms of action of its synthetic analogues remain unclear. Herein, a series of OA derivatives were synthesised and evaluated for their inhibitory effects on hyaluronidase. Compared to OA, an induction of fluorinated (6c) and chlorinated (6g) indole moieties led to enhanced anti-hyaluronidase activity (IC50 = 80.3 vs. 9.97 and 9.57 µg/mL, respectively). Furthermore, spectroscopic and computational studies revealed that 6c and 6g can bind to hyaluronidase protein and alter its secondary structure leading to reduced enzyme activity. In addition, OA indole derivatives showed feasible skin permeability in a slightly acidic environment (pH = 6.5) and 6c exerted skin protective effect by reducing cellular reactive oxygen species in human skin keratinocytes. Findings from the current study support that OA indole derivatives are potential cosmeceuticals with anti-hyaluronidase activity.  相似文献   
168.
The nematode-trapping fungusArthrobotrys ellipsospora developed an adhesive knob and trapped nematodes when cultured on a low-nutrient medium. It also trapped polystyrene beads in the same way. The adhesive knob produced mucus that was stained with alcian blue, while mycelium of the fungus was stained with periodic acid/Schiff (PAS). The amount of mucus increased with in days after culturing in the low-nutrient media. The fungus completely lost its ability to trap nematodes when treated with EDTA and EGTA, but it recovered the ability after incubation in the presence of a low concentration of Ca (10−6–10−7 M) for 1 h. Calmodulin inhibitor W-7 also inhibited the trapping ability of the fungus, and there was a significant (p<0.05) difference between the effects of W-7 and W-5. Ca-binding protein was also detected in the fungus.  相似文献   
169.
【目的】本文旨在探索SEF14菌毛特异性表达于D-群沙门氏菌,特别是肠炎沙门氏菌以及都柏林沙门氏菌的原因。【方法】应用PCR扩增以及序列测定检测了18株鸡白痢沙门氏菌,11株肠炎沙门氏菌以及1株都柏林沙门氏菌标准株中sefA,sefD和sefR基因序列,并分析比对其序列变异。【结果】以11株肠炎沙门氏菌以及1株都柏林沙门氏菌染色体DNA为模板能成功扩增sefA,sefD以及sefR基因;从18株鸡白痢沙门氏菌中均能成功扩增sefA基因,但只有分离于1980年之前的7株分离菌能成功扩增sefD和sefR基因,而另11株1980年后分离菌PCR扩增sefD和sefR基因却无任何产物。比对PCR扩增产物测序结果发现,11株肠炎沙门氏菌以及1株都柏林沙门氏菌株中sefA,sefD以及sefR基因序列和已发表的序列(GenBank登录号为L11008,U07129和AF233854)100%同源;7株鸡白痢沙门氏菌sefD基因测序结果表明,在196位点处发生碱基缺失,造成移码突变,提前于氨基酸残基71位点处产生终止密码子。优化菌毛表达条件,体外抽提和纯化菌毛并进一步试验证明:肠炎沙门氏菌以及都柏林沙门氏菌体外能很好表达SEF14菌毛,但鸡白痢沙门氏菌在相同培养条件下却无任何表达迹象。【结论】SEF14菌毛操纵子亚单位基因sefA,sefD以及调节基因sefR在不同沙门氏菌中的变异情况可能是SEF14菌毛局限性表达的原因之一。  相似文献   
170.
塔克拉玛干沙漠腹地胡杨林土壤细菌多样性分析   总被引:2,自引:0,他引:2  
【目的】对塔克拉玛干沙漠腹地胡杨林土壤细菌多样性进行初步探索,为下一步从中筛选可用于生物饲料或生物肥料的微生物奠定基础。【方法】采用可培养方法,进行细菌的分离纯化。对各菌株进行革兰氏染色及淀粉酶、酯酶、纤维素酶和NaCl耐受浓度的测定,并提取各菌株基因组DNA,进行16SrRNA基因扩增、测序及系统进化树的绘制,分析其多样性。【结果】共分离得到27株菌,其中放线菌门(Actinobacteria)16株,变形菌门(Proteobacteria)4株,厚壁菌门(Firmicutes)6株,拟杆菌门(Bacteroidetes)1株。革兰氏染色结果表明,5株菌为革兰氏阴性,其余为革兰氏阳性;酶活测定结果表明,15株菌具有淀粉酶活性,9株菌具有酯酶活性,9株菌具有纤维素酶活性;NaCl耐受浓度测定结果显示,NaCl浓度为2%时所有菌株均能生长,5%时能生长的有22株,15%时能生长的有1株。【结论】塔克拉玛干沙漠腹地胡杨林土壤中存在较丰富的细菌类群,且具有一定的酶学活性和NaCl耐受性,具有进一步研究开发的价值。  相似文献   
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