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Shahin Amani Amir Bagheri Garmarudi Niloofar Rahmani Mohammadreza Khanmohammadi 《RSC advances》2019,9(55):32348
Herein, the nanosized ZSM-5 zeolite was synthesized based on a fractional factorial experimental design by a hydrothermal method to study the optimum conditions for the synthesis and formation of the ZSM-5 zeolite by employing different conditions. The samples were synthesized without any organic template, and different conditions, such as the molar composition of the synthesis gel and reaction time, were applied in a wide range. Then, the samples were analysed by X-ray diffraction to investigate the formation of the zeolite ZSM-5, and the results were compared to obtain the optimum conditions for its synthesis. The obtained samples were characterized by SEM, FTIR spectroscopy and TGA. Then, the functionalization of nano zeolite ZSM-5 crystals with β-cyclodextrin (β-CD) was investigated. The zeolite surface was first functionalized with amino groups using an amino alkoxysilane. Then, toluene diisocyanate was reacted with the amino-terminated ZSM-5 zeolite crystals and used for the incorporation of β-CD via its remaining isocyanate groups. After this, a drug delivery system (DDS) was prepared based on the cyclodextrin-modified zeolite with the curcumin anticancer drug, and its formation was studied under experimental conditions. The results of in vitro studies show that this drug delivery system has better characteristics than free curcumin in terms of stability and anti-proliferative and anti-inflammatory effects.Herein, the nanosized ZSM-5 zeolite was synthesized based on a fractional factorial experimental design by a hydrothermal method to study the optimum conditions for the synthesis and formation of the ZSM-5 zeolite by employing different conditions. 相似文献
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A Toib HX Zhang TJ Broekelmann KL Hyrc Q Guo F Chen MS Remedi CG Nichols 《Journal of molecular and cellular cardiology》2012,53(3):437-445
Transgenic mice overexpressing SUR1 and gain of function Kir6.2[?N30, K185Q] KATP channel subunits, under cardiac α-myosin heavy chain (αMHC) promoter control, demonstrate arrhythmia susceptibility and premature death. Pregnant mice, crossed to carry double transgenic progeny, which harbor high levels of both overexpressed subunits, exhibit the most extreme phenotype and do not deliver any double transgenic pups. To explore the fetal lethality and embryonic phenotype that result from KATP overexpression, wild type (WT) and KATP overexpressing embryonic cardiomyocytes were isolated, cultured and voltage-clamped using whole cell and excised patch clamp techniques. Whole mount embryonic imaging, Hematoxylin and Eosin (H&;E) and α smooth muscle actin (αSMA) immunostaining were used to assess anatomy, histology and cardiac development in KATP overexpressing and WT embryos. Double transgenic embryos developed in utero heart failure and 100% embryonic lethality by 11.5 days post conception (dpc). KATP currents were detectable in both WT and KATP-overexpressing embryonic cardiomyocytes, starting at early stages of cardiac development (9.5 dpc). In contrast to adult cardiomyocytes, WT and KATP-overexpressing embryonic cardiomyocytes exhibit basal and spontaneous KATP current, implying that these channels may be open and active under physiological conditions. At 9.5 dpc, live double transgenic embryos demonstrated normal looping pattern, although all cardiac structures were collapsed, probably representing failed, non-contractile chambers. In conclusion, KATP channels are present and active in embryonic myocytes, and overexpression causes in utero heart failure and results in embryonic lethality. These results suggest that the KATP channel may have an important physiological role during early cardiac development. 相似文献
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Yen EF Pokhrel B Bianchi LK Roy HK Du H Patel A Hall CR Witt BL 《Digestive diseases and sciences》2012,57(1):161-169
Introduction
Microscopic colitis is currently considered to harbor no increased risk for colorectal cancer, based on a few small studies with limited long-term follow-up. Our aim was to identify patients with microscopic colitis, and to compare long-term rates of colorectal cancer or adenoma to a control group of patients without microscopic colitis. 相似文献109.
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Qaseem A Alguire P Dallas P Feinberg LE Fitzgerald FT Horwitch C Humphrey L LeBlond R Moyer D Wiese JG Weinberger S 《Annals of internal medicine》2012,156(2):147-149
Unsustainable rising health care costs in the United States have made reducing costs while maintaining high-quality health care a national priority. The overuse of some screening and diagnostic tests is an important component of unnecessary health care costs. More judicious use of such tests will improve quality and reflect responsible awareness of costs. Efforts to control expenditures should focus not only on benefits, harms, and costs but on the value of diagnostic tests-meaning an assessment of whether a test provides health benefits that are worth its costs or harms. To begin to identify ways that practicing clinicians can contribute to the delivery of high-value, cost-conscious health care, the American College of Physicians convened a workgroup of physicians to identify, using a consensus-based process, common clinical situations in which screening and diagnostic tests are used in ways that do not reflect high-value care. The intent of this exercise is to promote thoughtful discussions about these tests and other health care interventions to promote high-value, cost-conscious care. 相似文献