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PubMedDate not supplied

[Application of fluorescent probe spectrum analysis for the investigation of the structural state of sorbent. Heterogeneous binding sites].

A method is proposed for analyzing the fluorescence spectra of 1-anilinonaphthalene-8-sulphonate (ANS) and N-phenyl-1-naphthylamine (NPN) in the systems with nonuniform binding regions. Capacities of the method are demonstrated by analysing the fluorescence spectra of probes sorbed on bovine albumin molecules. It has been shown that there are two binding sites of the probes. Relative content of the probes in these binding sites was determined and their structural state was characterized (hydrophoby and microviscosity were estimated). The method described can be used to characterize the structural state of natural and artificial membranes.

1-Naphthylamine↗
PubMed1981

[Spectrum analysis of the electroencephalogram during electrohypoalgesia (combined with electroacupuncture) and pharmacological anesthesia].

Cerebral function has been monitored by means of the spectral analysis of EEG during general pharmacological anaesthesia and during electrohypoalgesia (auriculoacupuncture) in patients subjected to chest and heart surgery. The results have shown that during electrohypoalgesia, waking or subvigilance frequencies predominate, an aspect that is quite different from those recorded in patients subjected to general pharmacological anaesthesia. It is therefore demonstrated that electrohypoalgesia is useful for surgery and saves the patient from pharmacological aggression which, while on the one hand suppressing the state of awareness, along with its analgesic and neurovegetative protection action, is not free from risks and undesirable side-effects, particularly in high risk patients. The usefulness, harmlessness and simplicity of the method as an alternative to other anaesthesiological schedules is confirmed.

Acupuncture Therapy↗
PubMed1993

[Neural regulation of heart rate. Spectrum analysis of the RR interval in healthy subjects].

Dynamic 24-hour recordings were obtained in 10 healthy non hospitalized subjects. Spectral analysis of RR interval variabilities provided quantitative markers of sympatho-vagal balance throughout the day and night. The low frequency (0.1 Hz) component was considered a marker of sympathetic activity whereas the high frequency component (0.25 Hz) a marker of vagal tone. We observed an early morning rise in the sympathetic activity markers in all our patients, with a second smaller rise in the early afternoon. We believe this rise may be the trigger of the increased rate of major cardiovascular events reported to happen in the first hours of the morning.

Circadian Rhythm↗
PubMed1993

[Comparative evaluation of diabetic cardiac autonomic neuropathy by spectrum analysis and Ewing's tests].

METHODS: 62 diabetic patients of both sex (age: 46 +/- 16 yr, BMI: 26.1 +/- 4 kg/m2, casual blood pressure: 134 +/- 17/81 +/- 11 mmHg, mean age of diabetes: 11 +/- 9 yr) without cardiovascular medications were recruited. Autonomic involvement was based on the results from a battery of five cardiovascular tests as suggested by Ewing. The result of each test and a scoring system was considered. All patients underwent power spectral analysis (PSA) of digital blood pressure (BP) and RR intervals recorded in the recumbent position and after tilting with a Finapres monitor. The percentage of total power (0.025-0.4 Hz) computed in the low-frequency band (0.070-0.139 Hz) computed in the low-frequency band (0.070-0.139 Hz) was chosen as a sympathetic index (sigma Ind). Results of tests were correlated with sigma Ind. RESULTS: 24 patients (39%) have an autonomic involvement. The most affected tests are: the Valsalva maneuver (VAL): 16% RR response from lying to standing (LS): 25%, sustained handgrip (SHG): 30%, postural hypotension (PH); 57%, deep breathing (DB): 87%. Correlations coefficients of cardiovascular tests and sigma Ind are: VAL/sigma Ind (SBP tilt): r = 0.277, p = 0.029; Val/sigma Ind (DBP tilt): r = 0.318, p = 0.012; VAL/sigma Ind (RR tilt): ns. PH/Ind sigma (SBP tilt): r = 0.391, p = 0.0017; PH/sigma Ind (DBP tilt): r = -0.296, p = 0.019; PH/sigma Ind (RR tilt): r = -0.308, p = 0.015, DB/sigma Ind (SBP tilt): r = 0.417, p = 0.0007; DB/sigma Ind (DBP tilt): r = 0.361, p = 0.0039; DB/sigma Ind (RR tilt): ns. Results of LS and SHG show no correlation with Ind sigma. Correlations between global autonomic score (GAS) and sigma Ind during tilting have the following values: GAS/sigma Ind (SBP tilt): r = -0486, p = 0.0001; GAS/sigma Ind (DBP tilt): r = -0.385, p = 0.002; GAS/sigma Ind (RR tilt): r = -0.411, p = 0.0009. CONCLUSIONS: The so-called sympathetic index computed from PSA are well correlated with autonomic tests. They allow an early detection of sympathetic involvement in diabetics patients. These results are to consider while managing these subjects.

Autonomic Nervous System Diseases↗
PubMed1993

Speech-spectrum analysis of Mandarin: implications for hearing-aid fittings in a multi-ethnic society.

Using similar recording and analysis techniques, the long-term average speech spectra of English and Mandarin were compared in order to identify difference that might influence hearing-aid fitting strategies. Despite the well-documented pitch contour differences between English and Mandarin, no significant difference was found in the long-term average spectral analysis. Implications for hearing-aid prescription are discussed.

Adult↗