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991.
Jakub Herman Piotr Harmata Micha Czerwiski Olga Strzeysz Marta Pytlarczyk Monika Zajc Przemysaw Kula 《Materials》2021,14(16)
The synthesis and characterization of new deuterated liquid crystal (LC) compounds based on phenyl tolane core is described in this paper. The work presents an alternative molecular approach to the conventional LC design. Correlations between molecular structure and mesomorphic and optical properties for compounds which are alkyl-hydrogen terminated and alkyl-deuterium, have been drawn. The compounds are characterized by mass spectrometry (electron ionization) analysis and infrared spectroscopy. They show enantiotropic nematic behavior in a broad temperature range, confirmed by a polarizing thermomicroscopy and differential scanning calorimetry. Detailed synthetic procedures are attached. Synthesized compounds show a significantly reduced absorption in the near-infrared (NIR) and medium-wavelength infrared (MWIR) radiation range, and stand as promising components of medium to highly birefringent liquid crystalline mixtures. 相似文献
992.
For decades, one of the most critical considerations of civil engineers has been the construction of structures that can sufficiently resist earthquakes. However, in many parts of the globe, ancient and contemporary buildings were constructed without regard for engineering; thus, there is a rising necessity to adapt existing structures to avoid accidents and preserve historical artefacts. There are various techniques for retrofitting a masonry structure, including foundation isolations, the use of Fibre-Reinforced Plastics (FRPs), shotcrete, etc. One innovative technique is the use of Shape Memory Alloys (SMAs), which improve structures by exhibiting high strength, good re-centring capabilities, self-repair, etc. One recent disastrous earthquake that happened in the city of Bam, Iran, (with a large proportion of masonry buildings) in 2003, with over 45,000 casualties, is analysed to discover the primary causes of the structural failure of buildings and its ancient citadel. It is followed by introducing the basic properties of SMAs and their applications in retrofitting masonry buildings. The outcomes of preceding implementations of SMAs in retrofitting of masonry buildings are then employed to present two comprehensive schemes as well as an implementation algorithm for strengthening masonry structures using SMA-based devices. 相似文献
993.
994.
Kolesińska B Motylski R Kamiński ZJ Kwinkowski M Kaca W 《Acta poloniae pharmaceutica》2011,68(3):387-391
The new hybrid drugs combining in a single molecule triazine ring attached to phosphonium salt were prepared and their bactericidal activity against Gram-positive bacteria Staphylococcus aureus ATCC43300 (MRSA - methycyline resistant Staphylococcus aureus strain) two Gram-negative bacteria Escherichia coli CCUG31997 serotype O153 (EPEC - enteropathogenic Escherichia coli strain), Proteus mirabilis 1784 (MDR - multidrug resistant clinical strain) were determined using microdilution method. 相似文献
995.
996.
997.
Nowakowska E Kus K Polański A Burda K Nowakowska A Sadowski C 《Pharmacological reports : PR》2011,63(2):372-380
As shown in clinical studies, combinations of first generation normothymics (carbamazepine - CBZ) with atypical neuroleptics (olanzapine - OLA) lead to improvements in approximately half of patients treated for relapses of bipolar affective disease. Our previous studies have shown OLA to have an antidepressant effect when administered at a dose of 0.5 mg/kg only upon single administration; the effect did not last throughout chronic administration, whereas CBZ administered at a dose of 30 mg/kg showed an antidepressant effect only after 7 days of administration. As shown in our previous studies, both OLA and CBZ improve memory in rats but only after chronic administration. The improved antidepressant effect of many drugs, including OLA and CBZ used in combined therapy - as observed in our clinic - as well as confirmed evidence of OLA's and CBZ's positive effects on cognitive functions in humans and animals substantiated commencement of research on defining the effect of combined administration of OLA and CBZ on sedation (tested in a locomotor activity test), antidepressant effect (Porsolt test) and spatial memory (Morris test) in animals. The tests were performed on male Wistar rats. It was found that in combined administration of CBZ and OLA for 7 and 14 days, OLA would completely prevent the CBZ's sedative effect. With combined administration of CBZ and OLA, both as a single dose and after prolonged treatment for 7 days, a significant reduction in immobility time was observed. Combined administration of CBZ and OLA did not improve memory in rats that received these drugs in a single dose, whereas statistically significant differences were observed in the chronic experiments. It can be assumed that the observed effects of combined administration of CBZ and OLA may be due to the pharmacokinetic interactions, but further studies are necessary to confirm these assumptions. 相似文献
998.
This study aimed to compare the effects of ω-3 fatty acids and fibrate treatment on plasma levels and activities of hemostatic risk factors on glucose and lipid metabolism in subjects with isolated hypertriglyceridemia. Seventy-three subjects with elevated triglyceride levels were allocated into one of the following treatment options: bezafibrate (200 mg twice daily), ω-3 fatty acids (1 g twice daily) or placebo. Plasma lipids, glucose homeostasis markers (fasting and 2-h post-glucose load plasma glucose levels and HOMA), as well as plasma levels/activities of fibrinogen, factor VII and PAI-1 were determined at baseline, on the day of randomization, and after 4 and 12 weeks of the treatment. Not only did bezafibrate improve plasma lipids, but it also increased glucose sensitivity and tended to reduce post-glucose loads of plasma glucose. Except for the reduction in plasma triglycerides, ω-3 fatty acids produced no effect on the lipid profile and insulin sensitivity. Both treatment options reduced, to similar extents, plasma levels of fibrinogen and PAI-1 and factor VII coagulant activity. Our study indicates that, although fibrates exhibit more-pronounced metabolic effects than do ω-3 fatty acids, both these treatment options are equipotent in producing a complex beneficial effect on hemostasis in isolated hypertriglyceridemic subjects. 相似文献
999.
Łabuzek K Bułdak Ł Duława-Bułdak A Bielecka A Krysiak R Madej A Okopień B 《Pharmacological reports : PR》2011,63(5):1124-1136
In this study, we compared the effects of atorvastatin and fenofibric acid, which were administered alone or in combination, on the secretory function of human adipocytes that were obtained from the visceral and subcutaneous adipose tissues of 19 mixed dyslipidemic patients and 19 subjects with a normal lipid profile. The adipocytes were incubated in vitro in the presence of atorvastatin and/or fenofibric acid. The secretory function of the cells was determined using ELISA assays. The visceral adipocytes released significantly more adiponectin and IL-6 and less PAI-1 than those that were obtained from subcutaneous tissue. The levels and patterns of adipokine release differed between the patients with or without lipid abnormalities and between the adipocytes that were obtained from visceral or subcutaneous adipose tissue. The culture that contained hypolipidemic drugs resulted in the significant changes of the release of adipokines. The effects of atorvastatin and fenofibric acid on the hormonal function of human adipocytes may be, in part, responsible for the clinical efficacy of these drugs in the prevention and treatment of dyslipidemia-related cardiovascular and metabolic disorders. The study supports the concept that the pleiotropic effects of fenofibrate and atorvastatin may be, in part, a result of their impact on the secretory function of adipocytes. 相似文献
1000.
Ezetimibe is the first agent used in hypercholesterolemia treatment known to lower intestinal cholesterol uptake that is able to inhibit NPC1L1 transport proteins in the brush boarder of enterocytes and macrophages. Furthermore, it demonstrates anti-inflammatory and immunomodulatory properties and influences the expression of certain antigens. The drug is rapidly absorbed from the gastrointestinal tract and is then glucuronidated to form the active metabolite. It also undergoes extensive enterohepatic circulation. Various genetic polymorphisms seem to influence the pharmacokinetics of ezetimibe with different effects. The drug also presents a complex impact on cytochrome P450 enzymes, as it is a metabolism-dependent inhibitor of CYP3A4. Ezetimibe does not demonstrate any clinically significant interactions with statins, fibrates, mipomersen sodium, levothyroxine or lopinavir. However, its effect in conjunction with cyclosporine is not neutral. The use of this cholesterol absorption inhibitor has been shown to be safe and effective among patients after cardiac, renal and liver transplants, as well as in HIV patients. 相似文献