13 research outputs found
Eine verbesserte fluorimetrische Cortisolbestimmung im Serum
Die fluorimetrische Methode zur Bestimmung von Serumcortisol wurde durch blasenfreie Füllung einer Spezialküvette mittels Pumpvorrichtung, durch Benützung eines Spectralfluorimeters, sowie Verlegung des Meßzeitpunktes (80 min) und durch optimale Anregung (464 nm) und Emissionsmessung (522 nm) verbessert. Empfindlichkeit (<1 µg Cortisol/100 ml), Richtigkeit, Genauigkeit, Reproduzierbarkeit von Tag zu Tag (VK=6–7%) und Störfaktoren der Methode werden angegeben.
Mit dieser Methode wurden Normalberciche für die 9 Uhr-Nüchterncortisolwerte und die i.v. ACTH-Belastung ermittelt.
Bei NNR-insuffizienten Patienten (M. Addison; Zustand nach Operation eines Hypophysentumors; total Adrenalektomierte) wurden i.v. ACTH-Belastungen durchgeführt, wobei sich bereits beim 9 Uhr-Nüchterncortisolwert eine diagnostisch gut brauchbare Trennung gegenüber dem Normalbereich ergab. Unter Dexamethasonsubstitution wurden bei NNR-Insuffizienz sehr niedrige Cortisolspiegel gemessen, was für die Spezifität der Methode spricht.
Dic Bestimmung des 24 Std-Rhythmus der Cortisolwerte bei NNR-Insuffizienten zeigte, daß besonders in den frühen Morgenstunden im Vergleich zu Normalpersonen erniedrigte Cortisolspiegel bestehen. Daraus wird ein besserer Verteilungsvorschlag für die Cortisol-substitution abgeleitet.The fluorimetric determination of serum cortisol was improved
1. using a pumpdevice to fill a special microcuvette avoiding the development of small bubbles,
2. using a recording spectrofluorometer with optimal absorption (464 nm) and emission (522 nm), and
3. allowing for maximal fluorescence of cortisol (80 min).
Sensitivity (<1 µg cortisol/100 ml), accuracy, precision and specificity of the method are reported. Normal values of 9.00 a.m. serum cortisol (9.7–32.0 µg/100 ml) and of values before and after ACTH infusion tests were determined.
For adrenal insufficiency (Addisons disease, total adrenalectomy, or after hypophysectomy) the 9.00 a.m. values of serum cortisol were generally satisfactory for diagnosis. In partial adrenal insufficiency ACTH infusion tests had to be performed.
Very low levels of serum cortisol (2–4 µg/100 ml) were obtained, when patients with adrenal insufficiency were substituted with dexamethasone for three days, proving the specificity of the method.
Determination of circadian rhythms of serum cortisol in patients with adrenal insufficiency on cortisol substitutive therapy in divided doses demonstrated cortisol levels far below the normal values during the carly morning hours. This situation should be improved by dividing the cortisol dose as follows: 6 a.m.: 10 mg, 10 a.m.: 5 mg, 2 p.m.: 5 mg and 8 p.m. or later: 10 mg cortisol
Delivering Quality Software in Twenty-Four Hours
Our revolutionary process eliminates the trade-offs inherent in the long-term support of critical systems: frequent improvements vs. stability, rigorous testing vs. quick delivery and early testing vs. stable testing area. We now routinely place critical modifications in our customers' hands in 24 hours without compromising testing rigor. 1. Introduction Information technology support teams are frequently given the complicated task of supporting a critical software system with a long operational lifetime that must adapt to changes in organization, process and environment. Trade-offs between competing quality issues make supporting such a process feel like navigating a ship through narrow straits where rocks on either side must painstakingly be avoided. In this paper, we discuss several such dilemmas in the context of supporting software used in planning Hubble Space Telescope observations. We describe the process we developed to mitigate those trade-offs as well as several false start..