Biomedical subjects

W Heim

Publications and source records attributed to W Heim.

17 recordsLinked to original sources

PubMed2003

Systematic characterisation of silicon-embedded accelerometers for mechanomyography.

Silicon soft suction sockets (roll-on sleeves) currently used in passive prostheses for below-elbow amputees could also be used in externally powered prostheses, enhancing their functionality and comfort. However, as it is extremely difficult to hold currently used electromyography (EMG) sensors in place reliably within a silicon socket, an alternative measurement of muscular activity as the control input is necessary. Mechanomyography (MMG) is the epidermal measurement of the low-frequency vibrations produced by a contracting muscle. MMG sensors do not have to be in direct contact with the skin. Moreover, the embedding of sensors in the roll-on sleeve may also solve attachment issues, making sensor placement flexible. Therefore the objective was to determine the feasibility of recording MMG signals using silicon-embedded, micro-machined accelerometers. Fifteen embedded accelerometers were excited with predefined vibration patterns. The signal-to-noise ratio (SNR) and frequency response of each sample were measured and compared with those of non-embedded accelerometers. The SNR of embedded samples (approximately equal to 19 dB) was significantly higher than that of non-embedded samples (approximately equal to 12 dB), owing to the considerable mechanical damping effect of the silicon in the 300-900 Hz bandwidth (p=0.0028). This has implications for the application of silicon-embedded accelerometers for externally powered prosthesis control.

Amputation, Surgical↗

PubMed1994

Liberation of lithium from sustained release preparations. A comparison of seven registered brands.

We investigated the rate of release of seven commercial lithium preparations designated as sustained-release preparations and available in Europe and the USA. The examined products release lithium completely within four hours. The rate of liberation from three drugs resembles that of nonsustained-release preparations, three of which were tested under the same conditions. In one case, the comparison between two batches of sustained-release preparations reveals marked differences in quality. Physicians should be aware that some drugs available on the market and designated as sustained-release preparations do not comply with the international standard for this type of formulation.

Acetates↗

PubMed1991

A study of infusional cisplatin and infusional fluorouracil for locally advanced or metastatic non-small-cell lung cancer: a Mid-Atlantic Oncology Program study.

A combination of cisplatin administered as a 24-hour infusion and fluorouracil administered as a 5-day infusion was used to treat 97 patients with non-small-cell lung (NSCLC) cancer in a phase II trial. Thirty patients had stage IIIB disease; 67 patients, stage IV disease (new international classification). Patients with stage IIIB disease also received thoracic radiation after chemotherapy. The regimen was well tolerated, with 24% or less grade 3 or greater toxicities of all types. One toxic death was attributed to fluid overload. The response rate, partial and complete, was 43% (95% confidence interval, 27% to 63%), and median survival was 13.8 months for patients with stage IIIB disease. Response rates refer to the chemotherapy response. For patients with stage IV disease, the response rate was 34% (95% confidence interval, 24% to 47%), and median survival was 6.2 months. On this regimen, stable-disease patients with stage IV disease had survivals at least equal to responders.

Adult↗

PubMed1990

[Experience with ambulatory, preoperative autologous blood donation in heart surgery patients with special reference to hemodynamic parameters].

Our study is based on 843 autologous blood donations that we collected from 379 patients. The coronary angiogram, the diagnosis of the ventricles and the ergometry served to judge the patients suffering from a coronary insufficiency. The complication rate could be reduced to 1% with the help of volume substitution during the donation and the contraindications we ascertained. The exercise electrocardiogram proved to be a significant parameter of the complication rate. It was not the number and the extent of stenoses, but the interpretation of the myocardial oxygen supply that proved to be helpful for the diagnosis based on the evaluation of the coronary angiogram. Our technique of collecting blood and the assessment of the patients' ability as donors give even patients with highly affected coronary vessels the possibility of a preoperative autologous blood donation.

Blood Transfusion, Autologous↗

PubMed1980