Search PubMed⌕ Search

Biomedical subjects

H Vogel

Publications and source records attributed to H Vogel.

At least 343 records · Page 19Linked to original sources
PubMed1982

Unifying description of the effect of membrane proteins on lipid order. Verification for the melittin/dimyristoylphosphatidylcholine system.

The effect of melittin on lipid order in dimyristoylphosphatidylcholine bilayers is investigated by means of Raman spectroscopy and fluorescence anisotropy using diphenylhexatriene as fluorescence probe. In the fluid lipid phase, the Raman results indicate a slight increase in the conformational order of the lipid chains, and the fluorescence anisotropy results indicate a considerable increase in the rigid-body orientational order of the lipid chains. These results are contrasted with the reported decrease of the deuterium magnetic resonance order parameter. A consistent interpretation of the complete set of experimental data is presented according to which proteins induce a tilt of the preferred axes of lipid orientation and increase the orientational order with respect to these axes. The values of the tilt angle and the orientational order parameter at the surface of proteins are determined from the experimental data within a continuum model of lipid-protein interaction. The same values are obtained for melittin, Ca/Mg-ATPase, and cytochrome c oxidase, suggesting that different membrane proteins affect the lipid order in the same way.

Bee Venoms↗
PubMed1982

[Nephrotic syndrome as indication for one-stage bilateral renal embolisation (author's transl)].

A 42-year-old patient suffered from a nephrotic syndrome due to primary perireticular amyloidosis. One year after diagnosis the renal protein loss increased to 40 g/d within a short time so that sufficient substitution was no longer possible. The creatinine clearance was 7-10 ml/min so that haemodialysis was performed as a vital measure to remove excessive fluid. Two weeks later, as an alternative to surgical bilateral nephrectomy, simultaneous bilateral renal embolisation with Ethibloc was done without complications. A small artery to the left lower pole was spared from embolisation. Computer tomographic follow-up showed a residual parenchymal perfusion in the subcapsular and left lower pole areas so that metabolic functions of the renal parenchyma persisted. Plasma renin activity decreased to subnormal levels, the erythropoietin plasma level remained in the lower range of normal. "Medical binephrectomy" should be considered more often as a therapeutic alternative to surgery in therapy-resistant nephrotic syndrome on account of its advantage of preserved metabolic renal function.

Adult↗
PubMed1982

Somatosensory cortical potentials evoked by stimulation of leg nerves: analysis of normal values and variability; diagnostic significance.

An attempt was undertaken to assess the diagnostic value of sensory potentials evoked by stimulation of leg nerves. Findings in normal persons were as follows. First, stimulation of the sural nerve was superior to other methods, especially stimulation of the tibial nerve. Second, variations in latency were considerable and not attributable to age, height, or skin temperature. In many normal persons latency was not stable in either short-time or long-time trials. Amplitudes varied to such an extent that they could not help in diagnosis with the possible exception of extreme side-to-side differences. Finally, both amplitudes and latencies varied in relation to stimulus intensity, repetition rate, and filtering. Since sensory potentials from the leg nerves varied considerably, normal values must extend over a range that is wide enough to avoid mistaken diagnosis of abnormality. Hence, slight disturbances of nerve conduction such as those found in certain neuropathies, root damage and many extramedullary intraspinal space-occupying lesions could not be identified, whereas extensive demyelination in all parts of the sensory neuronal chain was readily discovered.

Adult↗
PubMed1982

Dependence of motion sickness in automobiles on the direction of linear acceleration.

Thirty-eight normal volunteers were tested in an ambulance car while being accelerated in one of the following positions: (1) sitting upright facing forward in the car, (2) lying supine on a stretcher head forward, (3) supine position head backward. Consecutive short period of negative horizontal acceleration (0.7-0.95 g) were achieved by brisk braking manoeuvres of the car, followed by weak reacceleration (0.15 g). Motion sickness symptoms were observed and recorded after each experiment using a special motion sickness scaling index which was weighted according to the strength of any particular symptom. The results indicate that horizontal linear acceleration in a car, such as experienced during multiple breaking manoeuvres, is an effective motion sickness provoking stimulus. Negative X-axis stimulation is more nauseogenic then acceleration in the Z-axis stimulation is more nauseogenic then acceleration in the Z-axis of the body.

Acceleration↗
PubMed1982

[Angiography after interventions on the pancreas].

The angiograms of 35 patients who had had surgery of the pancreas were evaluated. One must distinguish between the changes due to the procedure and those due to the original disease or to progress or recurrence of tumours. Out of four patients with recurrence of a pancreatic carcinoma, the angiogram failed to show any evidence in three. Angiography after pancreatic surgery is of value in planning further treatment, or if sonography and computer tomography are unable to clarify the problem.

Angiography↗
PubMed1982

[Effect of the intravenous administration of lormetazepam on hemodynamics and arterial blood gases in patients with coronary heart disease].

In 11 conscious patients suffering from coronary artery disease undergoing aorto-coronary bypass operations the hemodynamic and respiratory effects of Lormetazepam were investigated preoperatively. Lormetazepam was administered i.v. in a dosis of 2 mg (average weight 70.4 +/- 5.7 kg) into the right atrium. The maximum of hemodynamic changes was found about 10 min after injection. At that time the mean arterial pressure was diminished about 14%. At the same time total peripheral resistance fell about 15% below the control level. The cardiac index remained unchanged. The hemodynamic effect therefore consisted in a peripheral vasodilation. This was emphasized by the reduction of right atrial pressure and pulmonary capillary wedge pressure. The heart rate was unchanged. The arterial pO2 was reduced to 18% below the control level. The arterial pCO2 was increased about 24%. This finding is possibly due to an additional effect of Morphine and Phenobarbital used for premedication.

Anti-Anxiety Agents↗
PubMed1982

[Haemodynamic changes in infrarenal aortic aneurysm operations (author's transl)].

UNLABELLED: Haemodynamic changes after aortic cross-clamping were measured during operation of 11 patients suffering from infrarenal aortic aneurysm. Systemic vascular resistance, mean arterial pressure and pulmonary capillary wedge pressure are increased, while cardiac index is significantly decreased. Heart rate and right atrial pressure remain nearly unchanged. The elevations in systemic vascular resistance, mean arterial pressure and pulmonary capillary wedge pressure are reversed by continuous nitroglycerin infusion, cardiac index is increased. CONCLUSIONS: 1. meticulous haemodynamic monitoring is very important in operations including abdominal aortic cross-clamping in order to prevent imminent cardiac complications. 2. the haemodynamic changes induced by aortic cross-clamping can be reversed by infusion of nitroglycerin.

Aged↗
PubMed1982

[Perforations of the oesophagus (author's transl)].

The different reasons for perforations of the oesophagus are listed with their preferential locations. A survey is given on the necessary x-ray diagnostics including computed tomography according to the clinical signs. Examples of the characteristic x-ray findings and follow-up are demonstrated with their relation to the surgical possibilities.

Adult↗
PubMed1982

[Preoperative roentgendiagnostic of the naso-maxillary sinuses and operative findings (author's transl)].

The preoperative roentgenmorphology of the nasomaxillary sinuses was compared with the intraoperative findings. The dates of 285 patients were evaluated. For the maxillary sinus there was correspondency in 85.7%. There were no differences in the cases explored with tomography. For the ethmoidal sinus there was correspondency in 89.5% and for the frontal sinus in 82.7%. The importance of the preoperative roentgenexamination with the standard exposure in occipitomental projection was less the demonstration of the inflammation than of other findings. The sphenoidal sinus was best explored by tomography. The standard projection did not always allow the differentiation of cysts, polyps and mucoceles in diseased sinuses. The tomography was superior to the standard projection, in tumor patients the accompanying inflammation could not be separated from tumor infiltration with certainty.

Cysts↗
PubMed1982

[Mediastinal emphysema after thoracotomy (author's transl)].

A mediastinal emphysema was seen via x-ray film in 35 of 40 patients after opening of the mediastinum by longitudinal sternotomy. After about a week it was found in approximately every second patient; after 14 days it had been fully absorbed by all patients. Mediastinal emphysema could occur in conjunction with a cutaneous emphysema, and pneumothorax, respectively. Occasionally a pneumopericardium is seen even in the recumbent patient. Safe diagnosis of mediastinal emphysema is possible in the anterior lower mediastinum projected on to the cardiac silhouette if the x-ray film is taken obliquely.

Humans↗
PubMed1982

[X-ray findings of the sternum after sternotomy (author's transl)].

X-ray examination of the sternum after sternotomy supplies proof of rupture of a suture, of dehiscence of the sternum, malpositioning of the wire ligature, of the cutting-through of the fixation wire by the bone, of the fracture, pseudoarthrosis and inflammation. Fractures can be located in the manubrium sterni, the body of the sternum, the xiphoid process and in one of the two parts of the sternum. Pseudoarthroses can be seen in the manubrium, in the body of the sternum or as longitudinal pseudoarthroses. Pseudoarthroses were found only in conjunction with inflammatory chances. Signs pointing to an osteomyelitis of the sternum can be very discreet. This applies to both the reactive scleroses and to osteolyses. In individual cases the examination of a fistula system allows identification of a connection to the bone or to the ligature material. Retrosternal abscesses can be differentiated in the computer tomogram from dissections after bolus injection. Diagnosis by exclusion requires tomography in two planes with complicated blurs. In such cases the diagnostic reliability is probably far superior to the reliability achieved by plain roentgenography and with longitudinal blurring.

Abscess↗