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11.
Mahmoud Hassanein El-Saied A. Aly Yousf A. Abbas Samia M. El-Sigeny 《Macromolecular chemistry and physics.》1993,194(6):1817-1825
To overcome mass transfer limitations which are usually encountered on immobilizing active catalysts, cationic latex particles were used as support for the cobalt(II) complex of disodium N,N′-bis(salicylidene)ethylenediamine-5,5′-disulfonate ( 1 ). The cationic latex 2 was prepared by emulsion copolymerization of chloromethylstyrene (m/p-isomer mixture 60/40) and divinylbenzene (m/p-isomer mixture) followed by treatment with trimethylamine. The latexbound catalyst from 1 and 2 was found to considerably increase the reaction rate of the autoxidation of 2,6-di-tert-butylphenol in water as compared with the conventional polymer-free system. Reaction products were identified as the oxidative coupling product 3,3′,5,5′-tetra-tert-butyldiphenoquinone (3,3′,5,5′-tetra-tert-butyl-4,4′-dioxo-1,1′-bicyclohexa-2,5-dienylidene) and 2,6-di-tert-butyl-1,4-benzoquinone. All reactions showed an induction period before the start of dioxygen consumption. The rate of autoxidation in the three-phase mixtures of water, latex particles, and phenol droplets was not affected significantly by the method of mixing. The reaction rate increased as the concentration of 1 increased. Increasing the partial pressure of dioxygen in the range between 0,25 and 1,0 atm (2,53. 104 – 1,01. 105 Pa) gave a small increase in rate. The colloidal latex catalyst from 1 and 2 showed some loss of activity after successive runs. 相似文献
12.
Rejiba S Limam F Belhadj C Belhadj O Ben-Mahrez K 《Microbial drug resistance (Larchmont, N.Y.)》2002,8(1):9-13
Pseudomonas aeruginosa 802 was isolated at Rabta hospital in Tunis and was resistant to extended-spectrum cephalosporins and aztreonam. It produced a pI 7.6 extended-spectrum beta-lactamase (ESBL). The ESBL, named LBT 802, was purified to homogeneity by filtration on Sephadex G-75 followed by CM-Sepharose chromatography and high-performance liquid chromatography (HPLC) on a TSK-gel SP-5PW column. The LBT 802 enzyme had a molecular mass of 30 kDa. It showed a broad-substrate profile by hydrolyzing benzylpenicillin, ampicillin, cephalothin, cephaloridine, cefotaxime, ceftriaxone, and cefpirome but not ceftazidime, cefoxitin, imipenem, or aztreonam. The highest hydrolytic efficiency (Vmax/Km) was obtained for ampicillin, cephalothin, cephaloridine, and benzylpenicillin. Among extended-spectrum cephalosporins the best substrate was ceftriaxone followed by cefotaxime and cefpirome. LBT 802 activity was inhibited by clavulanic acid, sulbactam, imipenem, cefoxitin, and aztreonam. It showed its lowest Ki values for clavulanic acid, imipenem and sulbactam. 相似文献
13.
Salam Bennouar Abdelghani Bachir Cherif Amel Kessira Djamel-Eddine Bennouar Samia Abdi 《Nutrition Clinique et Métabolisme》2021,35(2):144-151
Introduction/ObjectivesAcute kidney injury (AKI) and malnutrition are two complications commonly reported in severe forms of COVID-19, their combined effect on short-term mortality is, however, not yet investigated. The objective of this study is to determine both their individual and combined effects on short-term prognosis.Materials and methodsThis is a prospective, uni-centric study, including 247 severe COVID-19 patients, admitted between April 25th and June 20th, 2020, at the University Hospital of Blida. AKI was defined according to the KDIGO-2012 guidelines. Nutritional status was assessed using the Controlling Nutritional Status (CONUT) score. The association with in-hospital mortality was assessed using the Kaplan-Meier method and proportional Cox regression.ResultsAmong the 247 severely affected COVID-19 patients included in this study, 34.4% developed AKI, 30.4 and 1.2%, respectively, had moderate and severe CONUT scores, 17.7% worsened and progressed to a critical state and 26.7% did not survive. Both AKI and CONUT score were significantly associated with mortality in a dose-response manner (pLog-Rank < 0.0001). Their relative risks are respectively (HR = 3.25 CI 95% [1.99–5.3] and HR = 2.42 CI 95% [1.5–3.9], p < 0.0001). In multivariate analysis, the highest risk was observed for the AKI-CONUT-high combination (HR = 3.0, 95% CI [1.5–6.1], p = 0.002).ConclusionA possible synergistic interaction between AKI and CONUT score for COVID-19 short-term mortality has been highlighted. Monitoring of renal function associated with assessment of nutritional status should be performed routinely and systematically from the early stages of admission. 相似文献
14.
Muhammad Jamshaid Samia Yousuf Nadeem Irfan Bukhari Amir Ali Rizvi 《European journal of drug metabolism and pharmacokinetics》2003,28(1):1-6
Three commercially available brands of amikacin were investigated in a parallel study design for the assessment of comparative pharmacokinetics in pediatric oncology patients with chemotherapy-induced neutropenic febrile episode. Amikacin concentration in serum samples was determined by fluorescence polarization immunoassay method using Abbott TDx system. Computer software, PK II was used for computation of pharmacokinetic parameters of amikacin. The serum concentration of all brands nonsignificantly (p > 0.05) varied at all time points, except at 1 and 2 hrs post dosing. At 1 hr post dosing, the serum concentration of brand II varied from rest of two brands. Whereas at 2 hr following I/V infusion, brands II and I were statistically different. Highest serum concentration of 38.69 +/- 1.45 microg/ml was observed in case of brand III while brands I and II showed lower but not significantly different serum concentration values, i.e., 36.30 +/- 1.65 and 37.89 +/- 1.32 microg/ml, respectively when compared with brand I. The other pharmacokinetic parameters of 3 brands found to have non-significant difference (P < 0.05) except, t(1/2)alpha and Cl of brands I and II that deviated statistically significant (p < 0.01). The relative bioavailability of brand II and III as compared with brand I, considered as standard 86.17 and 96.86%, respectively falls within the accepted limits of +/- 20% required for the bioequivalence of any two brands. Based upon findings of the present study, all these brands may be used interchangeably in oncology patients. Further studies, however are needed to determine whether the statistically elevated Cl value in brand II is of any clinical significance. 相似文献
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16.
Eduardo Alexandre Loth Samia Khalil Biazim José Henrique Fermino Ferreira dos Santos Rosana Puccia Rosimeire Costa Brancalh?o Lucinéia de Fátima Chasco Rinaldo Ferreira Gandra Rita de Cássia Garcia Sim?o Marcello Fabiano de Franco 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(3):259-264
Paracoccidioidomycosis (PCM) is caused by the dimorphic fungus
Paracoccidioides brasiliensis (Pb) and corresponds to prevalent
systemic mycosis in Latin America. The aim of the present work was to evaluate the
dose response effect of the fungal yeast phase for the standardization of an
experimental model of septic arthritis. The experiments were performed with groups of
14 rats that received doses of 103, 104 or 105
P. brasiliensis (Pb18) cells. The fungi were injected in 50 µL of
phosphate-buffered saline (PBS) directly into the knee joints of the animals. The
following parameters were analyzed in this work: the formation of swelling in knees
infused with yeast cells and the radiological and anatomopathological alterations,
besides antibody titer by ELISA. After 15 days of infection, signs of inflammation
were evident. At 45 days, some features of damage and necrosis were observed in the
articular cartilage. The systemic dissemination of the fungus was observed in 11% of
the inoculated animals, and it was concluded that the experimental model is able to
mimic articular PCM in humans and that the dose of 105 yeast cells can be
used as standard in this model. 相似文献
17.
An animal component free medium that promotes the growth of various animal cell lines for the production of viral vaccines 总被引:1,自引:0,他引:1
IPT-AFM is a proprietary animal component free medium that was developed for rabies virus (strain LP 2061) production in Vero cells. In the present work, we demonstrated the versatility of this medium and its ability to sustain the growth of other cell lines and different virus strains. Here, three models were presented: Vero cells/rabies virus (strain LP 2061), MRC-5 cells/measles virus (strain AIK-C) and BHK-21 cells/rabies virus (strain PV-BHK21). The cell lines were first adapted to grow in IPT-AFM, by progressive reduction of the amount of serum in the culture medium. After their adaptation, BHK-21 cells grew in suspension by forming clumps, whereas MRC-5 cells remained adherent. Then, kinetics of cell growth were studied in agitated cultures for both cell lines. In addition, kinetics of virus replication were investigated. 相似文献
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Report of a newly indentified patient with mutations in BMP1 and underlying pathogenetic aspects
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