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21.
22.
Hammad Ullah Alessandro Di Minno Cristina Santarcangelo Haroon Khan Jianbo Xiao Carla Renata Arciola Maria Daglia 《Molecules (Basel, Switzerland)》2021,26(8)
Helicobacter pylori (H. pylori) infections affect almost half of the world’s population, with gradually increasing incidence in developed countries. Eradication of H. pylori may provide significant benefits to the affected individual by healing a number of gastrointestinal and extra-digestive disorders. But due to increased microbial resistance and lack of patient adherence to the therapy, the eradication rate of H. pylori is below 80% with current pharmacological therapies. The usage of botanicals for their therapeutic purposes and medicinal properties have been increased in last decades. They can be use as alternative H. pylori treatments, especially against drug-resistant strains. Epidemiological studies have revealed that people with lower vegetable and micronutrient intake may be at increased risk of H. pylori infection. We have undertaken a review of clinical trials to evaluate the efficacy of vegetable extracts and micronutrients in patients with H. pylori. Various databases, such as Google Scholar, PubMed, Scopus, Web of Science, and the Cochrane Library, were searched for the articles published in English. A total of 24 clinical studies (15 for vegetable extracts and 9 for micronutrients) were selected to be reviewed and summarized in this article. Vegetable extracts (Broccoli sprouts, curcumin, Burdock complex, and Nigella sativa) and micronutrients (vitamin C and E) were not found to be as effective as single agents in H. pylori eradication, rather their efficacy synergized with conventional pharmacological therapies. Conversely, GutGard was found to be significantly effective as a single agent when compared to placebo control. 相似文献
23.
Ullah Malik Zaka Muhammad Taseer Mallawi Fouad 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2411-2418
Journal of Thermal Analysis and Calorimetry - This paper provides a theoretical study of 3D nanofluid flow with zero nanoparticles mass and constant heat fluxes conditions. An incompressible... 相似文献
24.
Nanostructured ZnSe-graphene/TiO2 was synthesized by a hydrothermal-assisted approach. ZnSe-graphene/TiO2 exhibited favorable adsorption of rhodamine B, a wide wavelength absorption range, and efficient charge separation. Reactive oxygen species were generated by the oxidation of 1,5-diphenyl carbazide to 1,5-diphenyl carbazone. The sonocatalytic reaction mechanism was pro-posed. These findings potentially broaden the applications of sonocatalytic technologies. 相似文献
25.
26.
Nazakat Ullah 《Pramana》1976,7(5):316-318
An exact differential equation is given to evaluate the energy average of the scattering function. The advantage of the differential
equation as compared to the earlier methods based on series expansion is that one has to evaluate only single sums over the
complex poles of the S-matrix. Using Wigner’s semicircle law for the distribution of the real parts of the poles of the scattering
matrix, the earlier expression for the energy average of the scattering function is rederived. 相似文献
27.
Nazakat Ullah 《Pramana》1983,20(2):131-135
An integral which occurs in the new matrix ensembles and the width fluctuation factor is evaluated using a transformation
which changes a Gaussian into an exponential. It is expressed in the form of a series whose terms are found using a simple
recursion relation. It is shown that the series can be summed in closed form for the two-dimensional case. 相似文献
28.
Nazar Mohammad Ranjha Ikram Ullah Khan Shahzad Naseem 《Journal of Sol-Gel Science and Technology》2009,50(3):281-289
Flurbiprofen loaded PCL/PVP blend microspheres were prepared by o/w solvent evaporation method using various concentrations
of gelatin as emulsifying agent. Microsphere recovery decreased with a decrease in the concentration of the emulsifier in
the dispersion. Encapsulation efficiency and drug loading of microspheres increased with decrease in concentration of emulsifying
agent. Hydration rate, encapsulation efficiency and drug loading of microspheres increased with increase in concentration
of PVP. Rheological properties showed free flowing nature of microspheres. SEM (Scanning electron microscope) revealed microspheres
were discrete, spherical and became porous with decrease in concentration of emulsifying agent but smooth with higher concentration
of emulsifying agent. FTIR (Fourier transform infrared spectroscopy) spectra of pure and encapsulated flurbiprofen in all
formulation showed no significant difference in characteristic peaks, suggesting stability of flurbiprofen during encapsulation
process. X-RD (X-ray powder diffractometry) of pure flurbiprofen shows sharp peaks, which decreases on encapsulation, indicating
dispersion at molecular level and hence decrease in the crystallinity of drug in microspheres. Microspheres showed an enteric
nature at pH 1.2 and a sustained release pattern at pH 6.8. Rapid drug release was observed in microspheres with higher concentration
of PVP (polyvinylpyrrolidone), PVP acts as channeling agent. Formulation with low concentration of emulsifying agent also
showed a fast release due to porous structure. Drug release kinetics followed zero order at pH 1.2 while at pH 6.8 Higuchi
model was best fitted and was found non fickian. 相似文献
29.
Suzuki-Miyaura cross-coupling reactions of tetrabromo-p-benzoquinone provide a convenient approach to tetraaryl-p-benzoquinones. 相似文献
30.
Herein, we propose a scheme for the realization of two-dimensional atomic localization in aλ-type three-level atomic medium such that the atom interacts with the two orthogonal standing-wave fields and a probe field. Because of the spatially dependent atom-field interaction, the information about the position of the atom can be obtained by monitoring the probe transmission spectra of the weak probe field for the first time. A single and double sharp localized peaks are observed in the one-wavelength domain. We have theoretically archived high-resolution and high-precision atomic localization within a region smaller thanλ/25×λ/25. The results may have potential applications in the field of nano-lithography and advance laser cooling technology. 相似文献