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1.
Leukemia ; 11(4): 609-11, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9096703

RESUMEN

A typical case of eosinophilic granulocytic leukemia with PML-RAR alpha fusion gene expression is reported. The patient achieved complete remission after oral administration of all-trans retinoic acid without any exposure to cytotoxic agents. The facts strongly suggest that the genetic event occurred at the level of pluripotent stem cells.


Asunto(s)
Leucemia Eosinofílica Aguda/genética , Proteínas de Neoplasias/análisis , Proteínas de Fusión Oncogénica/análisis , Tretinoina/uso terapéutico , Anciano , Femenino , Expresión Génica , Humanos , Leucemia Eosinofílica Aguda/tratamiento farmacológico , Inducción de Remisión , Tretinoina/farmacología , Células Tumorales Cultivadas/efectos de los fármacos
2.
Anal Bioanal Chem ; 355(2): 194-9, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-15045448

RESUMEN

Using PVC polymer as membrane matrix and di-n-octylphenyl phosphate (DOPP) as plasticizer, a piezoelectric crystal sensor (PCS) array with 12 adsorptive materials selected from 68 compounds by cluster analysis has been constructed as a perfume odour-sensing system. The frequency shift data obtained from the sensor array responding to four commercial perfume odours are first autoscaled and then treated by principal component analysis. The experimental results show that the plasticized PVC membrane PCS array provides improved performance of pattern recognition compared with the single adsorptive coating PCS array. The frequency shift response characteristics of these sensors have been investigated experimentally. The proposed sensor array has also been applied to the classification of commercial spirituous liquor, wine and soft drink samples, as well as aliphatic alcohol homologues and isomers.

3.
Talanta ; 34(6): 577-9, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18964363

RESUMEN

A pH-sensitive PVC membrane electrode based on methyldioctadecylamine as neutral carrier has been prepared. It gives linear response over the pH-range 3.0-11.0 and a slope of - 58.4 +/- 0.3 mV/pH (at 20 degrees). The electrode has fairly low resistance and good potential reproducibility. The selectivity and other characteristics of the electrode have been studied.

4.
Talanta ; 35(9): 707-11, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18964598

RESUMEN

It is shown theoretically and experimentally that the reliability of the analytical results obtained by Kalman filtering in multicomponent spectrophotometry can be judged by means of the normalized autocorrelation coefficient (NAC) of the innovation sequence. Variations of the initial values of the concentration vector X(0), the error covariance matrix P(0), and the measurement noise variance R over a wide range do not show a substantial effect on the computed results. The effect of the rounding-off errors associated with application of different forms of the equation for calculation of the error covariance matrix is also discussed.

5.
Talanta ; 32(12): 1163-6, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18963976

RESUMEN

A new low-polymer surfactant, poly(propylene oxide)-alpha-stearyldimethylammonium chloride (PPOSA) has been synthesized. It contains a polyglycol main chain and quaternary ammonium branched chains. Investigation of the surface-active properties of PPOSA showed that as a sensitizing and solubilizing reagent for spectrophotometric analysis it possesses some of the characteristics of both cationic and non-ionic surfactants. The surfactant shows a sensitizing effect superior or equal to that of classical surfactants commonly used in analytical chemistry. Use of PPOSA leads to development of some excellent micellar spectrophotometric procedures for determining trace metals.

6.
Talanta ; 41(2): 327-33, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18965930

RESUMEN

Four macrocyclic polyether derivatives of o-phenanthroline were synthesized and used as neutral carriers for preparing poly(vinyl chloride) (PVC) membrane electrodes to sense primary amine species. The potentiometric response characteristics of the electrodes prepared were investigated. The electrode sensitive to benzyl amine as model analyte showed a linear response range of 8.0 x 10(-6)-0.1 mol/l with a detection limit of 8.9 x 10(-7) mol/l and a slope of 56.5 mV/decade. The linear potentiometric response of the mexiletine-sensitive electrode was 4.7 x 10(-6)-0.1 mol/l, and the detection limit was 5.0 x 10(-7)1 mol/l with a slope of 59.0 mV/decade. The transfer behavior of amines and ammonium ions through an organic phase was investigated by means of the bulk liquid membrane transport experiment. The effects of pH, counter anions and other factors on the transfer of the amine and ammonium species were studied. The mass transfer rates of the test species facilitated by macrocyclic polyether derivatives of o-phenanthroline were determined and the following sequence was found: benzyl amine > ethyl amine > tetramethyl ammonium > triethyl amine > diethyl amine > K(+) > ammonium > Na(+) > Ca(2+) > Mg(2+). This was exactly the potentiometric selectivity sequence of the membrane electrodes prepared by using these carriers. The mechanism of transfer of benzyl amine through a membrane phase induced by the carriers has been elucidated on the basis of experimental observations.

7.
Talanta ; 30(6): 427-32, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18963389

RESUMEN

Several quaternary ammonium salts have been synthesized and comparisons made of their efficiency as exchange substrates in dicyanoargentate-sensitive electrodes. The electrode prepared from hexadecyltrioctylammonium dicyanoargentate shows the best performance characteristics and has been studied in more detail. Its Nernstian response range is 10(-1)-10(-4)M, the optimum pH range is 10.6-12.6, and the detection limit is 3 x 10(-5)M. It is suggested that the detection limit of the electrode is controlled by interference from cyanide ions, and the difference between detection limits obtained with the various electrodes is discussed in the light of this. Selectivity coefficients for various interfering ions have been determined and related to the extractability of the ions. The electrode has been applied to determination of silver in cyanide-containing plating solutions.

8.
Talanta ; 44(7): 1319-27, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18966869

RESUMEN

An optical chemical sensor has been prepared for the selective determination of o-nitrophenol in aqueous solutions based on the fluorescence quenching of curcumin in PVC membrane. The sensing mechanism of the proposed sensor for o-nitrophenol has been discussed in detail. The fluorescence changes of sensing membrane resulted from an associated complex formation between curcumin and o-nitrophenol. In pH 4.8 buffer solution, the sensor responds linearly in the measuring range from 1.0 x 10(-2) mol 1(-1) to 1.5 x 10(-4) mol 1(-1), and the experimental detection limit is evaluated to be 8.0 x 10(-5) mol 1(-1). A stable signal was obtained within less than 1.5 min. Under the optimum conditions, the sequence of selective response to the sensing membrane is o-nitrophenol > 2,4-dinitrophenol > m-nitrophenol > p-nitrophenol > 2,4,6-trinitrophenol. Phenol, aniline as well as other ions have less effect on the fluorescence of the sensor. The reproducibility for the determination of o-nitrophenol is better than 1%, and the response is reversible. The sensor can be used for the determination of o-nitrophenol in water samples.

9.
Talanta ; 31(11): 1041-3, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18963718

RESUMEN

2-(8-Quinolylazo)-7-phenylazochromotropic acid (QAPAC) has been synthesized by coupling diazotized 8-aminoquinoline with 2-phenylazochromotropic acid as well as by coupling diazotized aniline with 2-(8-quinolylazo)chromotropic acid. The properties of QAPAC and the spectrophotometric characteristics of some metal-QAPAC complexes are reported.

10.
Talanta ; 31(12): 1121-4, 1984 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18963736

RESUMEN

Pyrocatecholsulphonphthalein complexan (PSC) has been synthesized from Pyrocatechol Violet (PV), iminodiacetic acid and formaldehyde by Mannich condensation. Its acid dissociation equilibria have been studied potentiometrically. Some characteristic properties of Xylenol Orange (XO) and PV are found in PSC, which is slightly superior to XO and PV in sensitivity as a chromogenic reagent for bismuth. The spectrophotometric characteristics of some metal ion-PSC complexes are reported.

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