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51.
Tawanda M. Nyambuya Bongani B. Nkambule Sithandiwe E. Mazibuko-Mbeje Vuyolwethu Mxinwa Kabelo Mokgalaboni Patrick Orlando Sonia Silvestri Johan Louw Luca Tiano Phiwayinkosi V. Dludla 《Molecules (Basel, Switzerland)》2020,25(23)
Evidence on the beneficial effects of resveratrol supplementation on cardiovascular disease-related profiles in patients with type 2 diabetes (T2D) is conflicting, while its impact on renal function and blood pressure measurements remains to be established in these patients. The current meta-analysis included randomized controlled trials (RCTs) reporting on the impact of resveratrol supplementation on markers of renal function and blood pressure in patients with T2D on hypoglycemic medication. Electronic databases such as MEDLINE, Cochrane Library, Scopus, and EMBASE were searched for eligible studies from inception up to June 2020. The random and fixed effects model was used in the meta-analysis. A total of five RCTs met the inclusion criteria and involved 388 participants with T2D. Notably, most of the participants were on metformin therapy, or metformin in combination with other hypoglycemic drugs such as insulin and glibenclamide. Pooled estimates showed that resveratrol supplementation in patients with T2D lowered the levels of fasting glucose (SMD: −0.06 [95% CI: −0.24, 0.12]; I2 = 4%, p = 0.39) and insulin (SMD: −0.08 [95% CI: −0.50, 0.34], I2 = 73%, p = 0.002) when compared to those on placebo. In addition, supplementation significantly lowered systolic blood pressure (SMD: −5.77 [95% CI: −8.61, −2.93], I2 = 66%, p = 0.02) in these patients. Although resveratrol supplementation did not affect creatinine or urea levels, it reduced the total protein content (SMD: −0.19 [95% CI: −0.36, −0.02]; I2 = 91%, p = 0.001). In all, resveratrol supplementation in hypoglycemic therapy improves glucose control and lowers blood pressure; however, additional evidence is necessary to confirm its effect on renal function in patients with T2D. 相似文献
52.
Matshawandile Tukulula Stefan Louw Mathew Njoroge Kelly Chibale 《Molecules (Basel, Switzerland)》2020,25(24)
A second generation of 4-aminoquinoline- and 8-aminoquinoline-based tetrazoles and lactams were synthesized via the Staudinger and Ugi multicomponent reactions. These compounds were subsequently evaluated in vitro for their potential antiplasmodium activity against a multidrug-resistant K1 strain and for their antitrypanosomal activity against a cultured T. b. rhodesiense STIB900 strain. Several of these compounds (4a–g) displayed good antiplasmodium activities (IC50 = 0.20–0.62 µM) that were comparable to the reference drugs, while their antitrypanosomal activity was moderate (<20 µM). Compound 4e was 2-fold more active than primaquine and was also the most active (IC50 = 7.01 µM) against T. b. rhodesiense and also exhibited excellent aqueous solubility (>200 µM) at pH 7. 相似文献
53.
A. V. Pronin B. P. Gorshunov A. A. Volkov H. S. Somal D. van der Marel B. J. Feenstra Y. Jaccard J. -P. Locquet 《JETP Letters》1998,68(5):432-436
Direct measurements of the complex conductivity spectra of thin-film La2−2x
SrxCuO4 are made at frequencies of 5–40 cm−1. Narrow, intense Drude-type excitation is observed in the superconducting phase.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 5, 406–409 (10 September 1998) 相似文献
54.
F. W. Louw und W. E. Schilz 《Fresenius' Journal of Analytical Chemistry》1936,106(7-8):288
Ohne Zusammenfassung 相似文献
55.
N.J. Smeenk C. Mooney J. Feenstra P. Mulder T. Rohr C.O.A. Semprimoschnig E. Vlieg J.J. Schermer 《Polymer Degradation and Stability》2013
With the development of thin-film, high-efficient III–V solar cells using the epitaxial lift-off technique, flexible solar panels for space applications can be designed. Besides new deployment options, this also reduces the mass and thus launch costs of a satellite. One requirement for such a flexible panel configuration is the replacement of the brittle coverglass, which shields the solar cells from the harsh space environment, by a flexible alternative. In this work we have tested several compositions of a polysiloxane candidate material for a flexible shielding layer by exposing them to high energy UV and electron radiation at elevated temperatures. It was found that irradiation by electrons with a fluence corresponding to 15 years in space produces little degradation. UV radiation, on the other hand, has a more pronounced impact on the material properties, causing a discolouration of the transparent material and for some compositions even cracking of the samples. 相似文献
56.
57.
The title reaction, displaying peculiar characteristics as to relative rates and isomer distributions, has been studied in detail. Prior to this study, different mechanisms had been advanced by several groups. Kinetic features (isomer patterns, relative and absolute rates, reaction orders, influences of additives, H/D isotope effects) strongly point to a free-radical (chain) process, in which (1) is a crucial step. This abstraction reaction, endothermal by about 6 kcal/mol, apparently proceeds via a transition state closely resembling the free aryl radical. Relative rates and isomer distributions therefore reflect differences in stabilization energies, or in DH°(Ar – H). With high arene–Cl2 intake ratios or, more pronounced, with CCl4 as the reagent, aryl radicals also lead to biaryl, where arene successfully competes with the halogenating agent. This interpretation is quantitatively supported by our observation that “added,?” recognizable aryl radicals yield the same chlorination–arylation product ratio, and by the results of competitive chlorination of benzene and chloroform over a temperature range of 200°C, where the latter study substantiates the value DH0(C6H5 – H) ≈ 109 kcal/mol. 相似文献
58.
René Pool Jaap Heringa Martin Hoefling Roland Schulz Jeremy C. Smith K. Anton Feenstra 《Journal of computational chemistry》2012,33(12):1207-1214
We report on a python interface to the GROMACS molecular simulation package, GromPy (available at https://github.com/GromPy ). This application programming interface (API) uses the ctypes python module that allows function calls to shared libraries, for example, written in C. To the best of our knowledge, this is the first reported interface to the GROMACS library that uses direct library calls. GromPy can be used for extending the current GROMACS simulation and analysis modes. In this work, we demonstrate that the interface enables hybrid Monte‐Carlo/molecular dynamics (MD) simulations in the grand‐canonical ensemble, a simulation mode that is currently not implemented in GROMACS. For this application, the interplay between GromPy and GROMACS requires only minor modifications of the GROMACS source code, not affecting the operation, efficiency, and performance of the GROMACS applications. We validate the grand‐canonical application against MD in the canonical ensemble by comparison of equations of state. The results of the grand‐canonical simulations are in complete agreement with MD in the canonical ensemble. The python overhead of the grand‐canonical scheme is only minimal. © 2012 Wiley Periodicals, Inc. 相似文献
59.
Neugebauer J Zywietz TK Scheffler M Northrup JE Chen H Feenstra RM 《Physical review letters》2003,90(5):056101
Employing density-functional theory in combination with scanning tunneling microscopy, we demonstrate that a thin metallic film on a semiconductor surface may open an efficient and hitherto not expected diffusion channel for lateral adatom transport: adatoms may prefer diffusion within this metallic layer rather than on top of the surface. Based on this concept, we interpret recent experiments: We explain why and when In acts as a surfactant on GaN surfaces, why Ga acts as an autosurfactant, and how this mechanism can be used to optimize group-III nitride growth. 相似文献
60.
The Painlevé test for the parametrically driven sine-Gordon equation is performed. A new equation is derived which passes the Painlevé test. The connection with the integrability is discussed. 相似文献