Due to this atypical appearance, histological sampling is frequently required for definitive diagnosis (Figs. 9 and 10).
Histopathological analysis of tissue samples is frequently used (Spangehl et al. 1999, Bauer et al. 2006).
The concentration of pathogen DNA in biological samples is frequently very low, close to the detection limit.
Va, isolated from Sepia officinalis and Trachurus trachurus samples, is frequently detected from fin fish, shellfish, seawater, and sediment [ 7].
Availability of appropriate and clinically well-documented samples is frequently a major bottleneck for biomarker studies, even if all other aforementioned gaps are filled.
Transcriptomic analysis of the cancer samples is frequently performed, often being a good starting point for the identification of novel biomarkers for a given cancer type.
When it is necessary to establish a threshold, that is, the clinical decision point, for a quantitative continuous biomarker, obtaining appropriate validation samples is frequently the rate limiting step in assay validation, so it is wise for the team to establish the strategy (purchase commercially or collaborate, e.g).
However, dilute, large-volume biological samples are frequently encountered, especially in forensic or clinical laboratories.
The samples are frequently degraded and prone to contamination by DNA from other sources, and coaxing data out of the ancient material is costly and painstaking work.
Mass spectrometric detection is gradually replacing ultraviolet (UV) as the method of choice in bioanalysis, especially in the area of early drug discovery where high sensitivity and rapid sample throughput is required and where samples are frequently pooled or "cocktailed" prior to dosing or analysis.
