Coexistence of atomic and molecular chemisorption states: H(2)/Pd(210).

A novel H(2) molecular adsorption state on metal surfaces has been detected by temperature-programmed desorption and electron energy loss spectroscopy experiments of the H(2)/Pd(210) system. The molecular nature of this state has been verified by isotope exchange experiments. This molecular state leads to a decrease of the surface work function while atomic hydrogen on Pd(210) causes an increase. Ab initio total-energy calculations have confirmed all experimental findings. Through these calculations the microscopic nature of this novel molecular adsorption state could be identified; it turns out that this state is stabilized by the presence of atomic hydrogen on the Pd(210) surface.

Ageing of the cardiovascular system during 33 years of aerobic exercise.

BACKGROUND: increasing age affects aerobic capacity, with an average loss of 10% or more per decade. AIM: to determine the effect of ageing on the circulatory system in middle-aged men during 33 years of physical training. METHODS: 15 men initially aged 45 years took part in an exercise training programme for 25-33 years. Nine serial measurements were made at rest and during maximal effort. Aerobic training consisted of swimming, jogging, walking and cycling 3-4 times per week. Sessions were for 61-70 min at 77-84% of heart rate reserve. RESULTS: there was no change in resting heart rate, blood pressure, percentage fat or body composition. Minimal cardiovascular losses at maximal work included 5.8-6.8% in maximal oxygen uptake per decade, 25 beats in maximum heart rate and 26 beats in heart rate reserve. CONCLUSION: exercise training has a favourable effect on ageing of the cardiovascular system in older men, resulting in minimal loss of oxygen uptake, no rise in resting blood pressure and no change in body composition.

Hyper-Rayleigh light scattering from an aqueous suspension of purple membrane.

Here we report the first observation of hyper-Rayleigh light scattering from bacteriorhodopsin in the form of an aqueous suspension of unoriented purple membranes. A typical purple membrane suspension used in our experiments contains approximately 10(8) randomly oriented purple membranes. Each purple membrane contains approximately 10(5) bacteriorhodopsin molecules in a two-dimensional crystallinearray. Hyper-Rayleigh light scattering is observed when the purple membrane suspension is illuminated with light that has a wavelength of 1064 nm. We propose that the 532-nm scattered light from each of the bacteriorhodopsin molecules in a single purple membrane is coherent, and that the scattered light from different purple membranes is incoherent. This proposal is supported by the following experimental observations: (a) the 532-nm light intensity is proportional to the square of the incident power, (b) the intensity of the 532-nm signal is linearly proportional to the concentration of purple membrane in solution, (c) the scattered 532-nm light is incoherent, (d) the scattered 532-nm light intensity decreases if the size of the purple membranes is reduced while the bacteriorhodopsin concentration is kept constant, and (e) the 532-nm light is due to the retinal chromophore of the bacteriorhodopsin molecule. The ratio of horizontal polarized hyper-Rayleigh scattered light to vertically polarized hyper-Rayleigh scattered light gives the angle (23 ± 4°) of the retinal axis with respect to the plane of the purple membrane. The hyperpolarizability of the bacteriorhodopsin molecule is found to be 5 ± 0.4 × 10(-27) esu.

[Value of color-coded duplex sonography in diagnosis of extracranial vascular changes]. / Wertigkeit der farbkodierten Duplex-Sonographie bei der Diagnostik extrakranieller Gefässveränderungen.

72 patients at the age of 44 to 76 years with transitory ischaemic attacks which happened and for a short time reversible deficits, respectively, were diagnosed both conventionally duplex-sonographically and with the colour-coded duplex sonography under the question of vascular stenotic process in the region of the cervical vessels. After the ultrasound examination within two weeks an angiography was performed. As a result was shown that in 10 patients with an angiogram without pathological findings by means of the colour-coded duplex sonography in 3 cases plaque formations could be proved which could be clearly diagnosed only by colour marking.

[Acute and long-term effects of pimobendan (UD-CG 115) in NYHA II and III heart failure. Results of a randomized multicenter double-blind study]. / Akut- und Langzeiteffekte von Pimobendan (UD-CG 115) bei Herzinsuffizienz NYHA II und III. Ergebnisse einer randomisierten multizentrischen Doppelblindstudie.

The effects of pimobendan (UD-CG 115) on hemodynamics and exercise capacity after acute (single dose) and chronic (6 month) oral treatment, as well as acute treatment after 6 months were investigated in 67 patients with chronic heart failure of NYHA classes II or III, which had persisted in spite of treatment with diuretics and digitalis. They were treated with pimobendan (2.5 mg bid or 5 mg) or placebo in a randomized, double-blind multicenter trial. With a single administration before and after 6 months' treatment there was-compared to placebo-a significant fall in pulmonary capillary pressure (PCP) at rest (R) and during exercise (E) of 7% to 24%. Right atrial pressure (R) and pulmonary arterial pressure (PAP) (R, E) decreased after pimobendan on day 1; cardiac index (E) increased significantly. All other parameters were not influenced. After chronic therapy, PCP (E), PAP (E), LV stroke work index (E), and pulmonary resistance (R and E) values were significantly lowered by pimobendan when compared to day 1. Exercise duration was prolonged after 6 months by 83 s and 47 s after 5 and 10 mg/day, resp., compared to the placebo group (group difference not significant). Subjective wellbeing was improved in all three groups (no group difference). Clinical symptoms were not altered; six patients (two in each group) died suddenly. Another nine patients discontinued the trial prematurely because of poor efficacy or adverse events (no group difference). Overall, pimobendan was well-tolerated and had favorable effects on both acute and chronic hemodynamics and on exercise capacity. There was no evidence of any tolerance development.

[Experiences with the Günther filter]. / Erfahrungen mit dem Güntherfilter.

In the investigation 17 patients with lung embolism being cared for with a Guenther-filter were post-observed during a period up to two years. Early complications after the implantation of the Guenther-filter did not occur in any case. Late complications after the implantation of the Guenther-filter were dislocations, deformations of the filter and breaks of the spokes. In the result of the post-observation the Guenther-filter application despite its easy handling should be regarded very critically.

[Early complications after acute cerebrovascular insufficiency]. / Frühkomplikationen nach akuter zerebrovaskulärer Insuffizienz.

In the present paper the courses of the disease of 117 patients who due to an acute cerebrovascular insufficiency were admitted to the angiological department of a Dresden county hospital in the period from January 1989 to June 1990. Early complications which were frequently observed were urinary tract infections, pneumonias and recidivations of insult. On the basis of the results of examination can be confirmed that the prognosis is decisively determined by the ability of mobilisation during the first days.

[Experiences with color-coded duplex sonography in the diagnosis of extracranial vascular changes]. / Erfahrungen mit der farbkodierten Duplexsonographie bei der Diagnostik extrakranieller Gefässveränderungen.

72 Patients with occurred transitory ischemie attacks and passed reversible neurologie deficits were duplexsonographically diagnosed. After wards a renewed duplexsonographic investigation with color coding followed in all patients. The patients were angiographically diagnosed within two weeks. As a result in three of ten patients with an unobtrusive angiogramm plaques formations were proved by means of the color codes duplexsonography.

[Results of using EEG and carotid angiography for evaluating cerebrovascular insufficiency]. / Ergebnisse der Anwendung der EEG-Untersuchung und der Karotisangiographie zur Beurteilung der zerebrovaskulären Insuffizienz.

In the cerebrovascular disease the EEG can give references at localisation, extension and course. The ability of statement is increased by methods of provocation and activation. On 35 patients with cerebrovascular insufficiency can be indicated that there are good correlations between changes on the large cerebral supply vessels and changes of the EEG, in particular in the carotid pressure trial.

[Doppler sonography in the diagnosis of extracranial vascular changes]. / Doppler-Sonographie zur Diagnostik extrakranieller Gefässveränderungen.

On account of cerebrovascular insufficiencies or asymptomatic vascular noises which had taken place 45 patients were examined by means of Doppler sonography and after this by means of angiography. The judgement of the common carotid artery, the internal and external carotid arteries, the vertebral artery, the subclavian artery and the supratrochlear artery were involved into the ultrasound investigation. The sensitivity of the supratrochlear compression test was 50% in the diagnosis of high-degree stenoses and occlusions of the internal carotid artery, whereas the sensitivity of the complete ultrasound investigation way about 80%. The advantages and disadvantages of the ultrasound Doppler sonography investigation are discussed.

Static and dynamic differences among five types of skinfold calipers.

Thirty-eight skinfold calipers were compared in terms of dial accuracy, downscale force, and pressure at jaw openings of 10, 20, 30, 40, and 50 mm. Dynamic measures were made on four thicknesses of foam rubber. Foam rubber was used to simulate the compressibility of skinfolds and to eliminate subject and tester variability. Five caliper types were tested: 10 Harpenden (HRP), 9 Lange (LNG), 12 Slim Guide (85SG), 4 Skyndex (SKN), and 3 Lafayette (LF). Within-type variation was small and consistent across openings for dial accuracy, force, pressure, and foam rubber compressed thickness. Between-type pressures differed (p less than 0.01), with the HRP and LNG calipers having the highest but similar pressures and the SKN, LF, and 85SG calipers having the lowest but similar pressures. LF and LNG calipers (which differed from each other) had higher compressed foam rubber means than HRP, SKN, and 85SG calipers (p less than 0.01), which were similar to each other at three of four thicknesses. When average pressure was used as the covariate, differences between types were still large, with 97.5-99.3% of the variation explained by type. Compressibility of foam rubber was shown to be caliper specific. It is concluded that there are static and dynamic differences between the five major types of skinfold calipers. When measurer error is eliminated, the HRP, 85SG, and SKN calipers are similar to each other, but they give lower values than the LNG or LF calipers by approximately 50-100%, depending on compressed thickness. These differences should be noted when comparing skinfolds measured with dissimilar calipers.

Trace element-hormone-relations in the early course of myocardial infarction.

In 30 patients suffered from acute myocardial infarction the serum levels of zinc, copper, cortisol, aldosterone, and triiodthyronine were determined. Zinc and triiodthyronine decrease, the other parameters increase. The serum levels of the tested parameters show a characteristic course within the first days after onset of myocardial infarction. There are significant differences between patients without complications and patients with complicated course inclusive of deaths. The differences exist already on the day of admission. Therefore we conclude zinc, copper, cortisol, and aldosterone levels as well as the course of T3 level are useful for prognosis of the clinical progress fo AMI. The tested parameters are helpful in differential diagnosis of chest pains caused by myocardial ischemia with or without myocardial infarction. The strong correlations between trace elements and hormones show new aspects due to the explanation of pathological alterations of serum levels in clinical medicine.

[Lyme borreliosis--a possible cause of atrioventricular block]. / Lyme-Borreliose--eine mögliche Ursache von atrioventrikulären (AV-)Blockierungen.

Eight cases of Lyme borreliosis of clinical certainty with carditis are reported. In six patients, AV-blocks were predominant, two patients had a myopericarditis. Six acute cases were seropositive, but one case remained seronegative. The titer was border-line in that patient, who was studied 4 years after the acute disease. A Lyme carditis should be considered in each case, in which AV-blocks appear acutely.

[Mechanical properties of a new vena cava filter]. / Mechanische Eigenschaften eines neuen Vena-cava-Filters.

The construction and the mechanical properties of a percutaneous, transvenous implantable thrombus filter on the pulmonary embolism prophylaxis is introduced. The pressure loss by this filter amounted to nearly 1/60 in comparison with the Mobin-Uddin umbrella filter. The effect of partial occlusions by thrombus is estimated theoretically by means of technical models. The anchoring of the fresh implanted filter is guaranteed in case of embolisation with covering up to 85% of the open surface. A much faster anchoring is to be expected by reaction of the tissue after few days. It also resists in the most unfavourable case imaginable.