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1.
在温度220~260°C,压力5MPa,转筐转速2600r/min,空速1000~2000mL/(g·h)条件下,建立了工业级双功能混合催化剂上含氮合成气直接制二甲醚的宏观动力学模型,并获得了模型参数。统计检验和残差分析表明模型可靠。根据获得的宏观动力学及本征动力学的模拟计算,比较了两模型下温度及含氮量对反应的影响。由于含氮量影响反应组分的分压,进而影响CO的转化率,还通过影响反应组分在催化剂颗粒内的内扩散来影响产物的选择性,但总的结果是内扩散的存在减弱了催化剂的协同效应。  相似文献   
2.
The interaction between sulbactam and imipenem was evaluated with four clinical isolates of Acinetobacter baumannii, including two isolates resistant to imipenem, one of which produced IMP-1 metallo-beta-lactamase. Two isolates (one of which was imipenem-resistant) were sulbactam-resistant by undefined mechanisms. MICs were determined by standard broth microdilution methods. Time-kill assays with imipenem and sulbactam, alone or in combination at 0.5 x MIC and 1 x MIC, showed a synergic effect in all four isolates of A. baumannii after incubation for 0, 4, 8 and > 24 h at 35 degrees C.  相似文献   
3.
Osteoarthritis (OA) is the most common form of arthritis and a major cause of limited functionality and thus a decrease in the quality of life of the inflicted. Given the fact that the existing pharmacological treatments lack disease-modifying properties and their use entails significant side effects, nutraceuticals with bioactive compounds constitute an interesting field of research. Polyphenols are plant-derived molecules with established anti-inflammatory and antioxidant properties that have been extensively evaluated in clinical settings and preclinical models in OA. As more knowledge is gained in the research field, an interesting approach in the management of OA is the additive and/or synergistic effects that polyphenols may have in an optimized supplement. Therefore, the aim of this review was to summarize the recent literature regarding the use of combined polyphenols in the management of OA. For that purpose, a PubMed literature survey was conducted with a focus on some preclinical osteoarthritis models and randomized clinical trials on patients with osteoarthritis from 2018 to 2021 which have evaluated the effect of combinations of polyphenol-rich extracts and purified polyphenol constituents. Data indicate that combined polyphenols may be promising for the treatment of osteoarthritis in the future, but more clinical trials with novel approaches in the identification of the in-between relationship of such constituents are needed.  相似文献   
4.
There is evidence that B vitamins produce antinociception in animals. However, potentiation of NSAID‐induced antinociception by B vitamins is unclear. The current study was designed to investigate the antinociceptive interaction between a mixture of B vitamins and either acetaminophen or metamizol. Acetaminophen (56–316 mg/kg), metamizol (32–178 mg/kg), and the mixture of B vitamins (32–178 mg/kg of thiamine, pyridoxine, and cyanocobalamin in a 100:100:1 proportion, respectively) or a combination of each drug with the B vitamins mixture was administered orally to female Wistar rats, and the antinociceptive effect determined in the formalin test. Isobolographic analyses were used to define the nature of the interaction between NSAIDs and B vitamins. Oral administration of either drug produced a dose‐related antinociceptive effect. Isobolographic analyses revealed that both acetaminophen or metamizol and the B vitamins mixture interacted synergistically in the formalin test, suggesting that these two combinations could be useful in treating inflammatory pain states. Drug Dev. Res. 66:286–294, 2006. © 2006 Wiley‐Liss, Inc.  相似文献   
5.
目的 探讨拟康氏木霉胞外多糖(EPS)联合奥沙利铂(Oxa)用药对结肠癌细胞HCT116的协同抑制作用。方法 实验分为Control组(0 μg/mL)、Oxa组(8 μg/mL Oxa)、EPS组(100 μg/mL EPS)、EPS+Oxa组(8 μg/mL Oxa+100 μg/mL EPS)。CCK-8检测细胞活力,CompuSyn软件拟合Fa-CI曲线评价联用效果。流式检测凋亡和周期、划痕实验和transwell实验检测细胞迁移能力,Oxa和EPS相关基因与结直肠癌相关基因取交集进行PPI分析以及GO和KEGG富集分析。结果 Oxa单用或与EPS联用处理HCT116细胞,均可使HCT116细胞活力受到抑制,并呈现剂量与时间依耐性,两者联用有明显的协同作用(CI<1)。两药联用组的细胞总凋亡率与Oxa组以及对照组比较均显著升高(P<0.05);联合用药组处于S期的比例高于其他各组。EPS和Oxa均具有抑制HCT116细胞迁移的作用,两者联用后抑制作用更为明显。KEGG分析显示主要涉及耐药、凋亡、血管新生等通路。结论 EPS联合奥沙利铂可协同抑制HCT116细胞增殖,促进该细胞凋亡和细胞S周期阻滞、抑制细胞迁移,铂耐药、PI3K-Akt、MAPK等信号通路发挥了关键作用。  相似文献   
6.
7.
The increasing prevalence of hospital and community-acquired infections caused by multidrug-resistant (MDR) bacterial pathogens is rapidly limiting the options for effective antibiotic therapy. Systematic studies on combinations of already available antibiotics that could provide an effective treatment against MDR bacteria are needed. We tested combinations of antibiotics that target one important physiological function (peptidoglycan synthesis) at several steps, and studied Enterobacteriaceae (Klebsiella pneumoniae and Escherichia coli) for which multidrug resistance associated with ESBL-producing plasmids has become a major problem. To measure the effectiveness of antibiotics alone and in combination, we used checkerboard assays, static antibiotic concentration time-kill assays, and an improved in-vitro kinetic model that simulates human pharmacokinetics of multiple simultaneously administered antibiotics. The target strains included an MDR K. pneumoniae isolate responsible for a recent major hospital outbreak. A double combination (fosfomycin and aztreonam) and a triple combination (fosfomycin, aztreonam and mecillinam) were both highly effective in reducing bacterial populations in all assays, including the in vitro kinetic model. These combinations were effective even though each of the MDR strains was resistant to aztreonam alone. Our results provide an initial validation of the potential usefulness of a combination of antibiotics targeting peptidoglycan synthesis in the treatment of MDR Gram-negative bacteria. We suggest that a combination of fosfomycin with aztreonam could become a useful treatment option for such infections and should be further studied.  相似文献   
8.
Cationic antimicrobial peptides are a novel type of antibiotic offering much potential in the treatment of microbial-related diseases. They offer many advantages for commercial development, including a broad spectrum of action and modest size. However, despite the identification or synthetic production of thousands of such peptides, the mode of action remains elusive, except for a few examples. While the dogma for the mechanism of action of antimicrobial peptides against bacteria is believed to be through pore formation or membrane barrier disruption, some peptides clearly act differently and other intracellular target sites have been identified. This article presents an updated review of how cationic antimicrobial peptides are able to affect bacterial killing, with a focus on internal targets.  相似文献   
9.
Abstract

In this prospective study, consecutive isolates of Klebsiella pneumoniae were tested for different mechanisms of carbapenem resistance using the modified Hodge test (MHT), Rosco Neo-Sensitabs (ROSCO). Phenylalanine arginine beta-naphthylamide assay (PABN) inhibitor-based test was done on isolates in which the mechanism of resistance was not identifiable by the ROSCO. Among 105 selected isolates, carbapenemase production was noted in 100 (95%) by MHT and ROSCO showed 97 (92·4%) inhibition with dipicolinic acid signifying the production of MBL. PCR amplification was positive in 90 (86%) isolates for blaNDM-1 and 46 (44%) isolates for blaOXA-48. 54 (51%) isolates were positive for blaCTX-M and all belonged to blaCTX-M group 1. Isolates co produced blaOXA-48 (31/105, 30%) and blaCTX-M (40/105, 38%) in combination with the carbapenemase (blaNDM-1) gene. Five colistin-resistant isolates were positive for blaOXA-48. Eight isolates did not show inhibition with any of the inhibitor containing disks and found to be positive for blaOXA-48. Isolates were tested for colistin-meropenem synergy and detection rate was higher by the checkerboard (48%) than E-test method (35%). Our study necessitates continuous surveillance to recognize the predominant machinery of resistance in a particular geographical region to formulate effective control measures.  相似文献   
10.
当前医院信息化建设业务流程与财务流程相互独立、相互分散,数据之间缺乏有效沟通。以协同理论思维为指导,将医院财务与业务信息化统一谋划、系统建设,建立基于开放性、实时性、标准性、决策性和共享性的财务信息化协同管理模式,实现财务和业务的有机融合。  相似文献   
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