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1.
Ultrasound Obstet Gynecol ; 55(1): 81-86, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31559662

RESUMEN

OBJECTIVES: To measure the ratio of choroid plexus (CP) size to head size in normal fetuses and to compare it to that in fetuses with open spina bifida (OSB) and quantify the subjective sign of a 'dry brain'. METHODS: This was a retrospective study of ultrasound images, obtained during first-trimester screening between 11 and 13 weeks of gestation, from 34 fetuses with OSB and 160 normal fetuses. From the hospital databases, we retrieved images of the fetal head in the transventricular axial plane. We measured the areas of both CPs and the head and calculated the ratio between them. We also measured the longest diameter of each CP and calculated their mean (CP length), and measured the occipitofrontal diameter (OFD) and calculated the ratio of CP length to OFD. Measurements from the OSB fetuses were plotted on crown-rump length (CRL) reference ranges constructed using data from the normal fetuses, and Z-scores were calculated. RESULTS: In the normal fetuses, the CP area increased, while the ratios of CP area to head area and CP length to OFD decreased, with increasing CRL. In 30 of the 34 (88%) fetuses with OSB, both ratios were increased significantly and the CPs filled the entirety of the head, giving the impression of a dry brain. In these cases, the borders of the lateral ventricles could not be identified. CONCLUSIONS: At 11-13 weeks, the majority of fetuses with OSB have reduced fluid in the lateral ventricles such that the CPs fill the head. The dry brain sign is easily visualized during routine first-trimester ultrasound examination while measuring the biparietal diameter, and can be quantified by comparing the size of the CPs to the head size. Until prospective data confirm the usefulness of this sign in screening for OSB, it should be considered as a hint to prompt the examiner to assess thoroughly the posterior fossa and spine. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Disrafia Espinal/diagnóstico por imagen , Ultrasonografía Prenatal , Plexo Coroideo/diagnóstico por imagen , Bases de Datos Factuales , Femenino , Alemania , Cabeza/diagnóstico por imagen , Humanos , Embarazo , Primer Trimestre del Embarazo , Estudios Retrospectivos
3.
Fresenius J Anal Chem ; 371(4): 425-30, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11760049

RESUMEN

The hyphenation of gas-diffusion separation and ion chromatography (IC) is described as a convenient, reliable, robust, and economic method for in-line sample pre-treatment. The high selectivity associated with this method permits direct analysis of samples containing microparticulates, colloidal matter, and/or high molecular weight compounds. The determination of sulfite serves as a first example of its application. The method is based on the diffusional separation of SO2 following in-line oxidation with hydrogen peroxide to sulfate and final determination of the sulfate formed using IC. The influence of operational parameters has been thoroughly investigated and gas-diffusion cells of different geometries compared with respect to the gas-transfer rates obtained. Application to the analysis of wines demonstrates the utility of the method.


Asunto(s)
Cromatografía de Gases/métodos , Cromatografía por Intercambio Iónico/métodos , Cromatografía de Gases/instrumentación , Peróxido de Hidrógeno/química , Diseño de Software , Sulfitos/análisis , Dióxido de Azufre/química , Vino/análisis
4.
Thromb Res ; 100(5): 433-41, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11150587

RESUMEN

The paper describes the production of a prothrombin complex concentrate (PCC) with high virus safety and a well-balanced content of vitamin K-dependent clotting factors and inhibitors. Solid-phase extraction is followed in a second step by optimized anion exchange chromatography using a radial column. A step for virus removal by nanofiltration is introduced in addition to the solvent/detergent step. By speeding up the chromatographic step, the period of time required for production is reduced considerably. The activities of the four vitamin K-dependent clotting factors II, VII, IX and X are in ratios of about 1:1:1:1. Protein C, Protein S, and Protein Z are also present in therapeutically effective concentrations. The product shows no thrombogenicity, in either in vivo nor in vitro models. Clinical investigations show that the PCC is a safe and efficient preparation for the substitutive treatment of FIX or FVII in patients suffering from the respective deficiencies. All bleeding episodes have been efficiently controlled with relatively low doses of the concentrate. The surgical procedures have been conducted without any problems in severely FIX and FVIII deficient patients.


Asunto(s)
Protrombina/aislamiento & purificación , Animales , Humanos , Protrombina/farmacología , Protrombina/uso terapéutico , Ratas , Trombosis/prevención & control
5.
Talanta ; 52(1): 101-9, 2000 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-18967967

RESUMEN

Flow injection methods utilising the Karl Fischer (KF) reaction with spectrophotometric and potentiometric detection are described for the determination of the trace water content in various organic solvents. Optimisation of the methods resulted in an accessible (linear) working range of 0.01-0.2% water for many solvents studied with a typical precision of 1-2% R.S.D. Only 50 mul of organic solvent was injected and the sampling frequency was about 120 samples per h. Since the slopes of the calibration curves were different for different solvents appropriate calibration was required. Problems associated with spectrophotometric detection and caused by refractive index changes were pointed out and a nested-loop configuration was proposed to overcome this kind of interference. The potentiometric method with a novel flow-through detector cell was shown to surpass the performance of spectrophotometric detection in any respect. The characteristics of the procedures developed made them well applicable for on-line monitoring of technical solvent distillations in an industrial plant.

6.
J Rheumatol ; 23(9): 1605-11, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8877932

RESUMEN

OBJECTIVE: To compare the efficacy and tolerability of lornoxicam and diclofenac in the treatment of patients with osteoarthritis (OA) over 12 weeks and to assess the efficacy and tolerability of lornoxicam over a followup period of 40 weeks. METHODS: In a double blind, parallel group study, 135 patients (mean age 63 years) with OA of the hip and/or knee were randomized to receive lornoxicam 4 mg 3 times daily (tid), lornoxicam 8 mg twice daily (bid), or diclofenac 50 mg tid for 12 weeks. 85 patients who completed this 12 week treatment period subsequently received lornoxicam 4 mg tid or 8 mg bid for up to 40 weeks. RESULTS: Over the initial 12 week treatment period, intention-to-treat analysis revealed improvements in the functional index of severity for OA in all 3 groups by -1.5 to -1.9 points and pairwise testing demonstrated significant intergroup equivalence (p < 0.033). Confirmatory analysis demonstrated the expected efficacy as outlined in the sample size calculation. The percentage of patients showing improvements in disease activity (about 46%) and pain intensity (42 to 48%) was also similar and a clear majority of patients also reported "some" or "excellent" pain relief (80 to 89%). A per protocol analysis produced similar results. During the 40 week lornoxicam followup treatment period there was slight deterioration in the functional index of severity of OA (0.3 to 1.1 points). This minor change may reflect the natural course of the disease rather than a loss of efficacy in lornoxicam. Disease activity and pain intensity continued to improve but in a lesser proportion of patients (< 23%) compared to the previous phase. Nevertheless, a similar high percentage of patients (78 to 89%) reported "some" or "excellent" pain relief. Adverse events in both phases of this study were consistent with those commonly reported during treatment with nonsteroidal antiinflammatory drugs and included headache and gastrointestinal events. There was no difference in the frequency or severity of adverse events between any of the treatment groups. Lornoxicam was well tolerated in the long term. CONCLUSION: Lornoxicam 4 mg tid and 8 mg bid were as effective as diclofenac 50 mg tid for the treatment of OA. There was no significant difference in tolerability of these regimens. Thus, lornoxicam appears to be a useful therapeutic alternative to diclofenac in patients with OA.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Diclofenaco/uso terapéutico , Osteoartritis/tratamiento farmacológico , Piroxicam/análogos & derivados , Adolescente , Adulto , Anciano , Antiinflamatorios no Esteroideos/efectos adversos , Diclofenaco/efectos adversos , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/fisiopatología , Piroxicam/efectos adversos , Piroxicam/uso terapéutico , Resultado del Tratamiento
7.
Aliment Pharmacol Ther ; 10(2): 151-6, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8730243

RESUMEN

BACKGROUND AND AIM: Gastrointestinal effects are common adverse effects associated with nonsteroidal anti-inflammatory drugs (NSAIDs). Lornoxicam is a new nonsteroidal anti-inflammatory drug and its gastroduodenal tolerability was compared to that of naproxen in a randomized, double-blind, crossover study. METHODS: Eighteen healthy male volunteers received lornoxicam 8 mg b.d. or naproxen 500 mg b.d. administered orally over two 7-day dosing periods. Upper endoscopy was performed by two independent investigators at the beginning and end of each dosing regimen. RESULTS: Lornoxicam 8 mg b.d. caused significantly less mucosal injury than naproxen 500 mg b.d. in the stomach/duodenal bulb, as well as in the mid/distal duodenum. CONCLUSION: These findings may have favourable implications for lornoxicam in the clinical setting, if this dose provides optimal control of arthritic pain.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Naproxeno/efectos adversos , Piroxicam/análogos & derivados , Adolescente , Adulto , Estudios Cruzados , Método Doble Ciego , Endoscopía Gastrointestinal/métodos , Mucosa Gástrica/efectos de los fármacos , Humanos , Mucosa Intestinal/efectos de los fármacos , Masculino , Persona de Mediana Edad , Piroxicam/efectos adversos
8.
Anal Bioanal Chem ; 353(2): 123-7, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15048525

RESUMEN

Non-suppressed ion chromatography (NSIC) has been optimized to permit the determination of chloride, nitrate and sulfate in the low mg/l concentration range within 3 min. Using conductometric detection the extraneous (positive) injection peak was found to adversely affect the early eluting chloride signal when samples with high amounts of total cations are analyzed. The serial arrangement of a downstream potentiometric detector with a chloride ion selective electrode, which does not respond to other alterations of the composition of the eluent than the change in chloride concentrations, is shown to be suitable for interference-free, sensitive and reliable chloride evaluation. Application of the proposed system to the determination of chloride in extracts of filter collected airborne particulates revealed (for those samples that could be evaluated by both detection methods) high precision and no systematic deviations between conductometric and potentiometric detection.

9.
Talanta ; 41(11): 1965-71, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18966157

RESUMEN

This paper describes the application of the well-known Molybdenum Blue method for selective determination of arsenite in a flow injection system. Selectivity is achieved by on-line separation of the main interferents phosphate, arsenate and silicate using a strong anion-exchange microcolumn located in the aspiration line of injection valve. Arsenite passing through the microcolumn unretained is determined using Molybdenum Blue method following in-line oxidation to arsenate by permanganate. A thorough investigation of optimal experimental conditions for both, the separation of interferents and sensitive detection of arsenite is presented. The method developed permits arsenite to be determined in the concentration range 5-500 microg/l with high precision and reliability. A sample throughput of 20 hr(-1) is achieved. Phosphate, arsenate and silicate do not interfere at concentration levels significantly higher than that of arsenite. The application to real water samples reveals excellent recovery of spiked samples and the absence of matrix interferences.

10.
Talanta ; 39(7): 779-87, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18965451

RESUMEN

Chemical modification of nonionic sorbent Amberlite XAD-2 or anion exchanger Amberlyst A-26 with Eriochrome Blue-Black R (EBBR) produces a chelating resin of satisfactory chemical stability and resistance towards mineral acids. Retention of 10 metal ions has been examined for both resins. EBBR loaded XAD-2 was utilized for nickel(II) preconcentration in atomic-absorption spectrometry. In optimal conditions at a preconcentration time not exceeding 1 hr, nickel(II) can be determined at the 0.1 mug/l. level in flow measurements. Retention of metal ions on chelating resin is a convenient method of preconcentration and elimination of matrix interferences.

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