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Öğe The evaluation of coagulation profiles in calves with suspected septic shock(SPRINGER, 2006) Irmak, K; Sen, I; Col, R; Birdane, FM; Guzelbektes, H; Civelek, T; Yilmaz, AThe purpose of the study reported here was to evaluate the haemostatic function in calves with suspected septic shock and to reflect the occurrence of disseminated intravascular coagulation (DIC). Twenty-six calves suspected of having septic shock (experimental group) and 10 clinically healthy calves (control group) were used. On admission, the experimental group of calves had been ill for an average of 2 days. Therapy was applied to the experimental group of calves. The packed cell volume (PCV), haemoglobin (Hb), white blood cell (WBC), red blood cell (RBC) and platelet (PLT) counts were determined. Blood smears for toxic neutrophil and schistocyte intensity were evaluated. For the coagulation profile, plasma activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), fibrinogen and fibrin/fibrinogen degradation products (FDPs) values were determined. Toxic neutrophils in blood smears were observed in 12 calves of the experimental group. APTT was prolonged in the experimental group compared with the control group (p < 0.05). Fibrinogen concentration was found to be higher in the experimental group than in the control group (p < 0.001). Total leukocyte counts were higher in the experimental group compared with the control group (p < 0.01). Platelet counts in the experimental group were lower than the control group (p < 0.001). However, when the individual values of coagulation profiles of each calf were evaluated, 8 calves had at least three abnormal coagulation profiles (APTT > 72 s, PT > 34.5 s, TT > 33.7 s, FDPs > 5 mu g/ml, PLT <= 150 x 10(3)/mm(3)) and abnormal erythrocyte morphology (schistocytes >= 1). The most common abnormal tests in the coagulation profile were APTT and PT (7 cases), FDPs (6 cases), thrombocytopenia (4 cases), and schistocytes in blood smears (8 cases) in these 8 calves. The results of this study indicate that DIC might be a significant risk factor for mortality in calves with suspected septic shock.Öğe Synthesis and binding properties of calix[4]arene telomers(JOHN WILEY & SONS INC, 1999) Yilmaz, A; Memon, S; Yilmaz, MTwo calix[4]arene derivatives (5 and 8) and their telomers are synthesized to estimate selective extraction of alkali and transition metal cations from the aqueous to the organic phase (chloroform). Compound 5 shows selectivity toward Hg2+. Compound 8 and telomers 6 and 9 are not selective but are good extractants for all used transition metal ions. The observations suggest that ethylene glycol bridges are efficient for carrying transition metal cations in a two-phase solvent system. (C) 1999 John Wiley & Sons, Inc.Öğe Synthesis and extraction studies of a novel tetra-calix[4]arene(TAYLOR & FRANCIS INC, 2002) Yilmaz, A; Memon, S; Yilmaz, M[Abstract not Available]Öğe Synthesis and study of allosteric effects on extraction behaviour of novel calixarene-based dichromate anion receptors(PERGAMON-ELSEVIER SCIENCE LTD, 2002) Yilmaz, A; Memon, S; Yilmaz, MIn this study the selective derivatization of p-tert-butylcalix[4]arene was carried out and two new calix[4]arene-based azacrown ionophores, 5,17-di-tert-butyl-11,23-di-(methyl-3,5-dioxaoctane-1,8-diimine)-25,26,27,28-tetrahydroxycalix[4]arene (6), and 5,17-di-tertbutyl-11,23-di-(methyl-3,5-dioxaoctane-1,8-diimine)-25,27-diethoxyformyl-methoxy-26,28-dihydroxycalix[4]arene (7) have been synthesized. Treatment of 5,17-di-tert-butyl-11,23-diformylcalix[4]arene-25,26,27,28-tetrol (5) with 1,8-diamino-3,6-dioxaoctane gave the ionophore 6 which was converted to its diester derivative 7 by reaction with ethylbromoacetate in the presence of potassium carbonate. In the synthesis, the upper and lower rims of p-tert-butylcalix[4]arene were modified in order to acquire binding sites for the recognition of metal cations and dichromate anions. It was observed that receptor 7 is a better extractant for Cr2O72- anions than receptors 6. The protonated alkylinium form of 7 is an effective extractant for transferring the Cr2O72- anions from aqueous into a dichloromethane layer and failed in transferring Na+ cations due to the allosteric effect produced by the crown part of the calix moiety present at the p-position. (C) 2002 Elsevier Science Ltd. All rights reserved.Öğe Synthesis of polymeric calix[4]arene dinitrile and diamino-derivatives: Exploration of their extraction properties towards dichromate anion(MARCEL DEKKER INC, 2004) Memon, S; Yilmaz, A; Roundhill, DM; Yilmaz, MThe article describes the syntheses and extraction properties of new alkylnitrile and alkylamino substituted calix[4]arene based copolymers. These compounds have been synthesized via nucleophilic substitution reactions involving 5,11,17,23-tetra-tert-butyl-25,27-bis(cyanomethoxy)-26,28-dihydroxycalix[4]arene (3), or 25,27-bis(cyanomethoxy)26,28-dihydroxycalix[4]arene (4) with 1,5-dibromopentane and bisphenol-A, followed by their reduction with sodium borohydride in the presence Of CoCl2.6H(2)O. In addition an oligomer containing pendant calix[4]arene units with nitrile functionalities on its lower rim has been synthesized via nucleophilic reaction involving 5,11,17,23-tetra-tert-butyl-25,27-bis(cyanomethoxy)-26,28-dihydroxycalix[4]arene 3 with p-dibromoxylene. The extraction properties of polymers 5-9 toward the HCr2O7- anion are also reported. Due to the higher oxidative stability of nitrile groups, polymers 5-7 have been developed as good extractants for transferring the HCr2O7- anion from an aqueous into a dichloromethane phase.
