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At least 1,675 records · Page 93Linked to original sources
PubMed1990

[Spectral analysis and color-coded Doppler study of the changes in aortic regurgitation induced by vasodilators in asymptomatic patients with severe aortic insufficiency].

The acute effects of 20 mg of sublingual nifedipine in 12 patients with chronic severe aortic regurgitation were evaluated with M-mode echocardiography, continuous wave and colour Doppler. After nifedipine, heart rate increased from 68 +/- 8 to 82 +/- 11 beats/m' (p less than 0.001); arterial systolic and diastolic pressures decreased from 143 +/- 16 to 129 +/- 9 mmHg (p less than 0.01) and from 61 +/- 11 to 53 +/- 17 mmHg (p less than 0.01) respectively. Left ventricular systolic and diastolic diameters also decreased from 50 +/- 4 to 46 +/- 4 mm (p less than 0.01) and 76 +/- 6 to 72 +/- 6 mm (p less than 0.01) respectively; the slightly increase in fractional shortening which occurred was not significant. The aortic systolic and diastolic velocity integrals decreased from 38 +/- 9 to 34.7 +/- 8 cm (p less than 0.01) and from 203 +/- 41 to 163 +/- 29 cm (p less than 0.001); the diastolic slope of the velocity curve increased a little but significantly: from 334 +/- 70 to 394 +/- 70 cm/sec2 (p less than 0.01). With colour Doppler, protodiastolic jet areas decreased by 19% in the long parasternal view (p less than 0.01), by 28% in the apical view (p less than 0.001), by 26% in the short-axis view (p less than 0.01); the length of the jets in the long parasternal view decreased by 14% (p less than 0.001), but the height did not change significantly. Positive changes from acute nifedipine administration are present in this study.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve Insufficiency↗
PubMed1989

[Spectral analysis of electrocochleogram in Menière's disease].

The power spectrum of electrocochleogram in Ménière's disease was analysed. Usually, the ratio -SP/AP was used to diagnose Ménière's disease. However, when -SP could not be discriminated exactly, we were dubious of using this method. With power spectrum, we can raise the rate of diagnosis and estimate the condition of endolymphatic hydrops. In power spectrogram it shows more components of low frequency (that is, the power peak moves to the left) when the amplitude of -SP goes higher. Extratympanic electrocochleography was performed on 34 ears diagnosed as having Ménière's disease (MD group) and on 8 normal ears (normal group). An obvious difference in power spectrogram was found between these two groups (P less than 0.01). The peak in spectrogram of normal group was mean = 594 Hz; S = +60 Hz; the peak in MD group was mean = 359 Hz; S = +161 Hz. In MD group there were 28 cases (82.4%) with power peak moved to the left and 18 cases (52.9%) with the ratio -SP/AP no less than 0.4. During remission, the spectrum resembled the normal ones.

Adult↗
PubMed1989

[Power spectral analysis of heart rate in qi deficiency and both qi and yin deficiency in patients with coronary heart disease].

Qi deficiency (QD) and both Qi and Yin deficiency (QYD) are most common in TCM classification of CHD patients with insufficiency syndrome. The authors used the power spectrum of spontaneous heart rate fluctuation (PSHF) to analyze the function of cardiac regulation in 30 QD patients and 27 QYD patients with CHD and compare with the control group of 30 cases for discussing the association between different TCM syndrome patterns and the function of cardiac nerve regulation. The main results were as follows: (1) Low-frequency areas of PSHF in QYD (34.15 +/- 11.60%) were significantly higher than those in QD group (26.24 +/- 11.57%) and the control group (27.80 +/- 11.65%). The L/H ratio in QYD (1.78 +/- 0.96) was significantly higher than those in QD (0.91 +/- 0.64) and the control group (0.98 +/- 0.58). The changes of PSHF in QYD could have some relations with the increasing of the activity of sympathetic nervous system. (2) The change in body posture was used as a load test to study cardiovascular regulation in different TCM patterns of insufficiency syndrome with CHD. In control group the L/H ratio increased with the change of body posture from 0.98 +/- 0.58 to 4.29 +/- 0.89 (P less than 0.001), while in QD group and QYD group increased from 0.91 +/- 0.64 to 1.67 +/- 0.83 (P less than 0.05) and 1.78 +/- 0.96 to 1.85 +/- 0.87 (P greater than 0.2) respectively. The results suggested that cardiovascular baroreceptor reflex was decreased in CHD patients, and QYD group was inferior to DQ group.

Aged↗
PubMed1978

Spectral analysis of alpha rhythm during Schultz's autogenic training. A tentative approach to rapid visualization.

The records from experimental sessions including autogenic standard exercises and other conscious states, in two long-term trainees, were treated by using a frequency analysis programme. Starting from a synoptic reduced representation of the data and selecting sequences for the building of histograms of averaged energy levels in limited frequency bands, the authors describe the progressive spread of a dominant alpha band all over the scalp during autogenic training.

Adult↗
PubMed1985

Quantification of lumbar function. Part 3: Preliminary data on isokinetic torso rotation testing with myoelectric spectral analysis in normal and low-back pain subjects.

A prototype isokinetic torso rotation unit and an EMG signal processing system were utilized to obtain preliminary information on torso rotation. In Study 1, range-of-motion was found to be surprisingly uniform between low-back pain patients and normal subjects, although there was a significant strength variation between them at all isokinetic speeds tested. Both female patients and normal females showed approximately 70%-75% of the strength (torque/body weight) levels relative to their male counterparts. The decrement in trunk strength at high speeds was proportional for both patients and controls and was not nearly as dramatic as the decrement seen in the sagittal plane. In Studies 2 and 3, anatomic relationships evaluated by EMG testing of obliques and erector spinae showed that the contralateral abdominal obliques were the most consistent muscles providing a significant torsional moment to the spine.

Adult↗
PubMed1986

Characterization of a structural series of lipid A obtained from the lipopolysaccharides of Neisseria gonorrhoeae. Combined laser desorption and fast atom bombardment mass spectral analysis of high performance liquid chromatography-purified dimethyl derivatives.

Monophosphoryl lipid A (MLA) obtained from the lipopolysaccharides of serum-sensitive strains of Neisseria gonorrhoeae was fractionated on a silicic acid column to yield the hexaacyl and pentaacyl MLAs. The dimethyl derivative of the hexaacyl MLA was analyzed by proton nuclear magnetic resonance spectroscopy. The dimethyl esters of hexaacyl and pentaacyl MLAs were further purified by reverse-phase high performance liquid chromatography, and all of the peaks were analyzed by laser desorption mass spectrometry. Considerable structural information was obtained by laser desorption mass spectrometry due to three kinds of specific fragmentations of the sugar at the reducing end. Two major fractions were also analyzed by positive ion fast atom bombardment mass spectrometry. High performance liquid chromatography was able to separate the dimethyl MLA according to number, nature, and position of the fatty acyl groups. Since almost no structural information is available, the mass spectra of the samples were interpreted on the basis of the established structure of a model lipid A (hexaacyl MLA derived from Salmonella minnesota). Thirteen different structures of dimethyl MLA were identified. The four prominent dimethyl MLAs found in the fractionated samples were M1 (Mr = 1463), M2 (Mr = 1479), M3 (Mr = 1661), and M4 (Mr = 1677). These MLAs appear to have a 1'----6 linked glucosamine disaccharide backbone. The most prominent hexaacyl MLA was M3. We propose that it contains hydroxylaurate at the 3- and 3'-positions in ester linkage and lauroxymyristate at the 2- and 2'-positions in amide linkage of the glucosamine disaccharide. The most abundant pentacyl MLA was M2. We propose that it contains hydroxylaurate at the 3- and 3'-positions in ester linkage, lauroxymyristate at the 2'-position in amide linkage, and hydroxymyristate at the 2-position in amide linkage of the disaccharide. The lipid A of N. gonorrhoeae appeared to differ from that of the Salmonella strains by the presence of shorter-chain fatty acids and by the normal fatty acid distribution in the reducing and distal subunits.

Chromatography, High Pressure Liquid↗