Spectra of the voluntary first cough sounds.

The voluntary cough sounds recorded according to Korpas and Sadlonova-Korpasova were sampled at a frequency of 20.000Hz and spectra of six consecutive windows of 50ms were estimated. To digitize signals an autotrigger mode was used.

[Serum ferritin levels in elderly patients].

The authors examined, using the enzyme immunometric method, the serum ferritin concentration in 144 patients aged 60 to 93 years and in 26 healthy volunteers aged 22 to 30 years. They divided the group into four sub-groups: A control group of old people, B control group of young people, C patients with malignities and D patients with various diseases affecting the serum ferritin level. The authors confirmed the significant difference in the serum ferritin concentration between the two control groups (higher concentration in old people).

The origin of cough sounds.

We have analyzed the origin of the first and second cough sounds recorded by tussiphonography. About 10,000 tussiphonograms were performed in about 1,000 healthy and diseased subjects. Changes in the first cough sound are due to pathological processes in the airways, for example, the presence of mucus or acute inflammatory disease.