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71.
Mathias Prado Pereira Rafaela de Souza Martins Marcone Augusto Leal de Oliveira Fernanda Irene Bombonato 《RSC advances》2018,8(42):23903
In the present work, we describe the preparation of ten amino acid ionic liquids (AAILs) formed from ammonium salts as cations, derivatives of glycerol, and natural amino acids as anions. All of them are viscous oils, colorless or pale yellow, and hygroscopic at room temperature. They have appreciable solubility in many protic and aprotic polar solvents. The AAILs were used as catalysts in a Morita–Baylis–Hillman (MBH) reaction. The ionic liquids derivative from l-proline and l-histidine demonstrated the ability to catalyze the reaction between methyl vinyl ketone and aromatic aldehydes differently substituted in the absence of an additional co-catalyst under organic solvent-free conditions. The AAIL derivatives from l-valine, l-leucine, and l-tyrosine catalyzed the MBH reaction only in the presence of imidazole. The MBH adducts were obtained in moderate to good yields. Although the catalytic site in the ILs was in its enantiomerically pure form, all the MBH adducts were obtained in their racemic form.In this work, we describe the preparation of ten amino acid ionic liquids (AAILs). The AAILs were used as catalysts in a Morita–Baylis–Hillman (MBH) reaction. The MBH adducts were obtained from moderate to good yields and in their racemic form. 相似文献
72.
Mohamed R. Saber Gomaa Khabiri Ahmed A. Maarouf Mathias Ulbricht Ahmed S. G. Khalil 《RSC advances》2018,8(46):26364
MoS2 is a very attractive material and has been well studied for potential applications in various areas. However, due to the wide variety of factors affecting the molecular and electronic structure of MoS2, several contradictory reports about the adsorptive and photocatalytic properties of such materials have been published. In most of these reports, the effect of the actual phase of the materials on the properties was neglected. Here, different phases of MoS2 nanosheets (1T/2H, 1T/3R and 2H) have been obtained using the hydrothermal method with different Mo : S molar ratios and different autoclave filling ratios. The obtained materials have been thoroughly characterized using Raman, UV-vis, powder XRD, SEM, TEM and XPS measurements in order to accurately identify the existing phases in each material. A comparative study of the photocatalytic organic dye degradation efficiency under white light irradiation has been conducted using methyl orange to correlate the different activity of each material to the respective phase composition. The results indicate a much higher performance of the 1T/2H phase compared to the 2H and 3R phases. Detailed computational studies of the different phases revealed the emergence of mid-gap states upon introducing 1T sites into the 2H lattice. This leads to the improvement of the photocatalytic activity of 1T/2H compared to the other prepared materials.MoS2 is a very attractive material and has been well studied for potential applications in various areas. 相似文献
73.
Dennis Hanke Maria Jenckel Anja Petrov Mathias Ritzmann Julia Stadler Valerij Akimkin Sandra Blome Anne Pohlmann Horst Schirrmeier Martin Beer Dirk H?per 《Emerging infectious diseases》2015,21(3):493-496
Since 2013, highly virulent porcine epidemic diarrhea virus has caused considerable economic losses in the United States. To determine the relation of US strains to those recently causing disease in Germany, we compared genomes and found that the strain from Germany is closely related to variants in the United States. 相似文献
74.
Miedany Yasser El Gaafary Maha El Toth Mathias Hegazi Mohamed Osama Aroussy Nadia El Hassan Waleed Almedany Samah Nasr Annie Bahlas Sami Galal Salwa 《Clinical rheumatology》2021,40(10):4225-4232
Clinical Rheumatology - The prevalence of sarcopenia with osteoporosis results in a higher risk of falling and fractures. It was noted that patients who had completed their planned 5-year denosumab... 相似文献
75.
76.
Kröger N Einsele H Wolff D Casper J Freund M Derigs G Wandt H Schäfer-Eckart K Wittkowsky G Schmitz N Krüger W Zabelina T Renges H Ayuk F Krüll A Zander A;German Study-group Multiple Myeloma 《Bone marrow transplantation》2003,31(11):973-979
We investigated toxicity and efficacy of in vivo T-cell depletion with anti-thymocyte globulin (ATG) as part of an intensified myeloablative conditioning regimen followed by allogeneic stem cell transplantation in patients with advanced multiple myeloma. The conditioning regimen consisted of modified total body irradiation, busulfan and cyclophosphamide (n=15) or in the case of prior dose-limiting radiotherapy of busulfan and cyclophosphamide (n=3). The median age was 44 years (range, 29-53) and the median time from diagnosis to transplant was 12 months (range, 6-144). Grade II-IV acute graft-versus-host disease (GvHD) occurred in six patients (35%). Severe grade III/IV GvHD developed in one patient (6%). Three patients died of therapy-related causes (17%). A complete remission (CR) with negative immunofixation after allogeneic transplantation was seen in eight of the evaluable patients (53%). After a median follow-up of 41 months (range, 8-84), the estimated overall survival at 6 years for all patients is 77% (CI 95%: 58-96%). The estimated progression-free survival at 6 years for all patients is 31% (CI 95%: 2-59%) and 46% (CI 95%: 9-83%) for patients with CR. In vivo T-cell depletion with ATG resulted in a low rate of severe GvHD with low treatment-related mortality, and a substantial number of long-term survivors. 相似文献
77.
Focal congenital alveolar proteinosis associated with abnormal surfactant protein B messenger RNA 总被引:3,自引:0,他引:3
Two siblings presented with typical clinical features of congenital pulmonary alveolar proteinosis (PAP). Necropsy of one sibling revealed scattered foci of the diagnostic histologic changes in the lung tissue. In contrast to infantile and adult PAP, focal distribution is uncommon in congenital PAP. Defective expression of the granulocyte-macrophage colony-stimulating factor receptor was ruled out. The surfactant protein B (SP-B) content in the lung tissue of the autopsied patient was low, and a deletion in the SP-B messenger RNA was detected. We speculate that the PAP in our patients was related to the reduced quantity and/or to the altered quality of SP-B. 相似文献
78.
Alves PM de Freitas EJ Mathias HA da Motta AE Silva Rde C Müller M Almeida SF Stapleton E Timerman S Ramires JA 《Arquivos brasileiros de cardiologia》2001,76(4):310-314
After the incorporation of automated external defibrillators by other airlines and the support of the Brazilian Society of Cardiology, Varig Airlines began the onboard defibrillation program with the initial purpose of equipping wide-body aircrafts frequently used in international flights and that airplanes use in the Rio - S?o Paulo route. With all flight attendants trained, the automated external defibrillation devices were incorporated to 34 airplanes of a total fleet of 80 aircrafts. The devices were installed in the baggage compartments secured with velcro straps and 2 pairs of electrodes, one or which pre-connected to the device to minimize application time. Later, a portable monitor was address to the resuscitation kit in the long flights. The expansion of the knowledge of the basic life support fundamentors and the corrected implantation of the survival chain and of the automated external defibrillators will increase the extense of recovery of cardiorespiratory arrest victims in aircrafts. 相似文献
79.
Camila Alexandrina Figueiredo PhD Maurício Lima Barreto Neuza Maria Alcantara-Neves Laura Cunha Rodrigues Philip John Cooper Alvaro A. Cruz Lain Carlos Pontes-de-Carvalho Denise C. Lemaire Ryan dos Santos Costa Leila D. Amorim Candelaria Vergara Nicholas Rafaels Li Gao Cassandra FosterMonica Campbell BS Rasika A. Mathias Kathleen C. Barnes 《The Journal of allergy and clinical immunology》2013
80.
Shinji Naganawa Rintaro Ito Yutaka Kato Hisashi Kawai Toshiaki Taoka Tadao Yoshida Katsuya Maruyama Katsutoshi Murata Gregor Krzdrfer Josef Pfeuffer Mathias Nittka Michihiko Sone 《Magnetic resonance in medical sciences》2021,20(1):91
Purpose:To evaluate the feasibility for the detection of slight contrast effects after intravenous administration of single dose gadolinium-based contrast agent (IV-SD-GBCA), the time course of the GBCA distribution up to 24 h was examined in various fluid spaces and brain parenchyma using 3D-real IR imaging and MR fingerprinting (MRF).Methods:Twenty-four patients with a suspicion of endolymphatic hydrops were scanned at pre-administration and at 10 min, 4 and 24 h post-IV-SD-GBCA. 3D-real IR images and MRF at the level of the internal auditory canal were obtained. The signal intensity on the 3D-real IR image of the cerebrospinal fluid (CSF) in the cerebellopontine angle cistern (CPA), Sylvian fissure (Syl), lateral ventricle (LV), and cochlear perilymph (CPL) was measured. The T1 and T2 values of cerebellar gray (GM) and white matter (WM) were measured using MRF. Each averaged value at the various time points was compared using an analysis of variance.Results:The signal intensity on the 3D-real IR image in each CSF region peaked at 4 h, and was decreased significantly by 24 h (P < 0.05). All patients had a maximum signal intensity at 4 h in the CPA, and Syl. The mean CPL signal intensity peaked at 4 h and decreased significantly by 24 h (P < 0.05). All patients but two had a maximum signal intensity at 4 h. Regarding the T1 value in the cerebellar WM and GM, the T1 value at 10 min post-IV-GBCA was significantly decreased compared to the pre-contrast scan, but no significant difference was observed at the other time points. There was no significant change in T2 in the gray or white matter at any of the time points.Conclusion:Time course of GBCA after IV-SD-GBCA could be evaluated by 3D-real IR imaging in CSF spaces and in the brain by MRF. 相似文献