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21.
Z Kalina B Okopień A Madej D Tokarz A Ma?lankiewicz Z Szwed V Gross-Furek ZS Herman 《Canadian Metallurgical Quarterly》1998,137(7):281-285
OBJECTIVE: The present study was undertaken to evaluate the efficacy and safety of amlodipine for hypertension treatment in comparison with nifedipine retard. METHODS: We examined 31 patients with arterial blood pressure approximately 155-165 mmHg/100-105 mm Hg at the beginning of the trial. It was a randomized double-blind, parallel-group trial including two groups of patients. Patients of the first group were given active amlodipine and nifedipine retard placebo during 6 weeks, while the second group was given active nifedipine retard and amlodipine placebo. Statistical analysis was made using the paired Student's t-test, chi-square test and ANOVA test. RESULTS: At end point we observed significant decrease in arterial blood pressure after treatment of both drugs. The treatment with nifedipine retard increased the mean heart rate of patients. Amlodipine therapy in comparison to nifedipine retard did not change the heart rate in treated patients. Safety parameters: SGOT, SGTP, creatinine and others were in laboratory norms ranges. CONCLUSION: Amlodipine proved to be an effective, more safe and better-tolerated therapeutical alternative for hypertension management than nifedipine retard. 相似文献
22.
Scholfield C. R. Nowakowska Janina Dutton H. J. 《Journal of the American Oil Chemists' Society》1961,38(4):175-177
Corn oil has been fractionated in a 200-tube countereurrent distribution apparatus. Although this technique gives no information
about the positional isomers of the glycerides, the fatty acid composition of the fractions and the amounts of the more unsaturated
triglycerides are in agreement with an essentially random pattern.
Presented at fall meeting. American Oil Chemists’ Society, New York, N.Y,, October 17–19, 1960.
This is a laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, U.S. Department
of Agriculture. 相似文献
23.
The influence of different treatments (in H2 or in O2 at 250 or 600 °C) of alumina supported Ru catalysts on the total oxidation of propane was investigated. Ruthenium catalysts were prepared using RuCl3 as metal precursor and characterized by H2 chemisorption, O2 uptake, BET, XRD and TEM. The presence of chloride on the catalyst surface was found to exert an inhibiting effect on the activity of Ru. The reduced Ru/γ-Al2O3 catalysts after partial removing chlorine ions were more active than the same samples oxidized at 250 °C. The higher activity of the reduced Ru/γ-Al2O3 catalysts was attributed to the presence of a large amount of active sites on small Ru x O y clusters without well defined stoichiometry or on a poorly ordered layer of a ruthenium oxide on the larger Ru particles. The formation of highly dispersed, but in some extent crystallized RuO2 phase in catalysts oxidized at 250 °C, leads to slightly lower activity of the Ru phase. Strong decline of the activity was found for catalysts oxidized at 600 °C. At this temperature, the Ru particles were completely oxidized to well-crystallized RuO2 oxide, and the mean crystallite size of the Ru oxide phase was much higher (9–25 nm) than that of after oxidation at 250 °C (~4 nm). The effect of the regeneration treatment in H2 on the activity of the Ru/γ-Al2O3 catalysts was also studied. The active ruthenium species for propane oxidation were discussed based on the catalytic and characterization data both before and after activity tests. 相似文献
24.
Felix Kexel Alexandra von Kameke Janina Tenhaus Marko Hoffmann Michael Schlüter 《化学,工程师,技术》2021,93(5):830-837
A consecutive competitive gas-liquid reaction is investigated using a Taylor bubble setup regarding the influence of fluid mixing in the bubble wake on yield and selectivity. The concentration fields behind a Taylor bubble are visualized and measured quantitatively with a novel time-resolved absorption imaging technique based on Beer Lamberts law and an integral selectivity is derived. In addition, the calculation of the local selectivity, often used in numerical approaches, is discussed and the existing experimental limits for its derivation are pointed out. Finally, an increase in selectivity of a competitive consecutive reaction for enhanced mixing is experimentally confirmed. 相似文献
25.
26.
Kiwilsza Anna Milanowski Bartłomiej Drużbicki Kacper Coy L. Emerson Grzeszkowiak Mikołaj Jarek Marcin Mielcarek Jadwiga Lulek Janina Pajzderska Aleksandra Wąsicki Jan 《Journal of Porous Materials》2015,22(3):817-829
Journal of Porous Materials - Two mesoporous silica materials: MCM-41 and SBA-15 were applied as potential nanocarriers for poorly soluble drug—nimodipine. Drug incorporation was performed... 相似文献
27.
Bettina Grauel Christian Würth Christian Homann Lisa Krukewitt Elina Andresen Janina Roik Sebastian Recknagel Markus Haase Ute Resch-Genger 《Nano Research》2022,(3):2362-2373
Despite considerable advances in synthesizing high-quality core/shell upconversion(UC)nanocrystals(NC;UCNC)and UCNC photophysics,the application of near-infrare... 相似文献
28.
Janina Tokarz Gabriele Mller Anna Artati Simone Huber Anja Zeigerer Bert Blaauw Jerzy Adamski Kenneth Allen Dyar 《International journal of molecular sciences》2021,22(15)
Biological aging research is expected to reveal modifiable molecular mechanisms that can be harnessed to slow or possibly reverse unhealthy trajectories. However, there is first an urgent need to define consensus molecular markers of healthy and unhealthy aging. Established aging hallmarks are all linked to metabolism, and a ‘rewired’ metabolic circuitry has been shown to accelerate or delay biological aging. To identify metabolic signatures distinguishing healthy from unhealthy aging trajectories, we performed nontargeted metabolomics on skeletal muscles from 2-month-old and 21-month-old mice, and after dietary and lifestyle interventions known to impact biological aging. We hypothesized that common metabolic signatures would highlight specific pathways and processes promoting healthy aging, while revealing the molecular underpinnings of unhealthy aging. Here, we report 50 metabolites that commonly distinguished aging trajectories in all cohorts, including 18 commonly reduced under unhealthy aging and 32 increased. We stratified these metabolites according to known relationships with various aging hallmarks and found the greatest associations with oxidative stress and nutrient sensing. Collectively, our data suggest interventions aimed at maintaining skeletal muscle arginine and lysine may be useful therapeutic strategies to minimize biological aging and maintain skeletal muscle health, function, and regenerative capacity in old age. 相似文献
29.
Spudat C Müller M Houben L Maultzsch J Goss K Thomsen C Schneider CM Meyer C 《Nano letters》2010,10(11):4470-4474
We study collective vibrational breathing modes in the Raman spectrum of a multiwalled carbon nanotube. In correlation with high-resolution transmission electron microscopy, we find that these modes have energies differing by more than 23% from the radial breathing modes of the corresponding single-walled nanotubes. This shift in energy is explained with intershell interactions using a model of coupled harmonic oscillators. The strength of this interaction is related to the coupling strength expected for few-layer graphene. 相似文献
30.
It is indispensable to modify the physical properties of egg white prior to a fractionation of the included bio-functional proteins. It was already demonstrated that this can be realized with mechanical devices. However, until now, it was not clear by which kind of molecular changes this is accompanied. Thus, this study reports on the molecular changes in egg white proteins induced by various mechanical treatments (high-pressure homogenizer, colloid mill, toothed disc dispersing machine). Evaluation criteria were the particle size of the long-chain protein ovomucin, the content of thiol groups, and disulfide bridges in egg white as well as the amount of free lysozyme. In general, it was shown that these treatments led to changes in the molecular structure and that the obtained modifications were more pronounced the higher the applied energy was. In detail, it was found that the applied mechanical forces in the experimental range of this study were able to disrupt strong covalent bonds in the fibrillar protein ovomucin. Additionally, the bio-functional protein lysozyme that is partly entrapped in the natural egg white structure was released by the applied forces. Summing up, this study generates comprehensive knowledge concerning the underlying mechanisms that enable the release of lysozyme as well as the use of egg white for fractionation processes. 相似文献