Quantitative diagnosis

Principle The principle behind the quantitative diagnosis of liver functions is to administer defined test sub-... 

The knowledge model used for fault diagnosis is developed from some fundamental understanding of the physics of the process. In this chapter, a unified approach to bond graph model-based qualitative and quantitative FDl is addressed. Causality in bond graph models has been exploited in different ways to arrive at various qualitative and quantitative diagnosis schemes. The relative merits and demerits of these schemes are assessed. 

Bond Graph Model-Based Quantitative Diagnosis... 

A diagnosis procedure based on evaluation of physical constraint laws derived from bond graph models is described here. Symbolically written constraints, called analytical redundancy relations (ARRs), are expressed in terms of known variables (measurements and inputs). ARRs are static or dynamic constraints which link the time evolution of the known variables when a system operates according to its normal operation model. The error or deviation from the constraint model is called a residual. The objective of quantitative diagnosis is to evaluate the residuals and associate the fault symptoms with deviations of residuals. 

Wang B, Gao Z, Zou Q, Li L (2003) Quantitative diagnosis of fatty liver with dual-energy CT. An experimental study in rabbits. Acta Radiol 44 92-97... 

Metabolic disorders of urea biosynthesis, while extremely rare, illustrate four important principles (1) Defects in any of several enzymes of a metabolic pathway enzyme can result in similar clinical signs and symptoms. (2) The identification of intermediates and of ancillary products that accumulate prior to a metabolic block provides insight into the reaction that is impaired. (3) Precise diagnosis requires quantitative assay of the activity of the enzyme thought to be defective. (4) Rational therapy must be based on an understanding of the underlying biochemical reactions in normal and impaired individuals. 

After confirming the diagnosis of syphilis, the desired outcome is a four-fold decrease in quantitative non-treponemal titers over a 6-month period and within 12 to 24 months after treatment of latent or late syphilis. An algorithm for the treatment of syphilis is shown in Fig. 77-1. 

Kramer. M. A., Malfunction diagnosis using quantitative models with non-Boolean reasoning in expert systems, AlChE J. 33,1130-140 (1987). 

The diagnosis of PK deficiency depends on the determination of quantitative enzyme activity or qualitative abnormalities of the enzyme. In 1979, the International Committee for Standardization in Haematology (ICSH) established methods for the biochemical characterization of red blood cell PK variants (M22). Since the establishment of these methods, many PK-deficient cases have been characterized, including 13 cases of homozygous PK deficiency. Residual red blood cell PK activity is not usually associated with phenotypic severity,whereas enzymatic characteristics such as decreased substrate affinity, thermal instability, or impaired response to the allosteric activator fructose-1,6-diphosphate (F-1,6-DP) correspond to a more severe phenotype. 

The advent of personalized therapies that are dependent on the outcome of an immunohistochemical stain has increased the need for quantitative positive controls. When IHC was first introduced as an adjunct in surgical pathology diagnosis, the interpretation was largely qualitative. Specific markers were present or absent, thereby characterizing a tumor cell s lineage. The fact that IHC interpretation was qualitative, rather than semiquantitative, minimized... 

Becker KF, Schott C, Hipp S, et al. Quantitative protein analysis from formalin-fixed tissues implications for translational clinical research and nanoscale molecular diagnosis. /. Pathol. 2007 211 370-378. 

Patients with type 2 DM should have a routine urinalysis at diagnosis as the initial screening test for albuminuria. If positive, a 24-hour urine for quantitative assessment will assist in developing a treatment plan. If the urinalysis is negative for protein, a test to evaluate the presence of microalbuminuria is recommended. 

Diagnosis Oa consumption Very simple and economical not quantitative Glass capillary tubing (ST)... 

In analytical redundancy schemes, the resulting difference generated from the consistency checking of different variables is called a residual signal. The residual should be by convention zero-valued when the system is normal and should diverge from zero when a fault occurs. This zero and non-zero property of the residual is used to determine whether or not a fault has occurred. Analytical redundancy makes use of a quantitative model of the monitored process and is therefore often referred to as the model-based approach to fault diagnosis. 

Buist, A. S., and B. B. Ross. Quantitative analysis of the alveolar plateau in the diagnosis of early airway obstruction. Amer. Rev. Respir. Dis. 108 1078-1087, 1973. 

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