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1.
Phys Rev Lett ; 87(9): 096103, 2001 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-11531580

RESUMEN

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.

2.
Age Ageing ; 28(6): 531-6, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10604504

RESUMEN

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.


Asunto(s)
Envejecimiento/fisiología , Fenómenos Fisiológicos Cardiovasculares , Ejercicio Físico/fisiología , Adulto , Presión Sanguínea/fisiología , Composición Corporal/fisiología , Metabolismo Energético/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Oxígeno/sangre
3.
Appl Opt ; 33(19): 4286-92, 1994 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20935785

RESUMEN

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.

4.
Z Gesamte Inn Med ; 46(16): 621-3, 1991 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-1792804

RESUMEN

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.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Ecoencefalografía/instrumentación , Interpretación de Imagen Asistida por Computador/instrumentación , Ataque Isquémico Transitorio/diagnóstico por imagen , Adulto , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Femenino , Humanos , Arteriosclerosis Intracraneal/diagnóstico por imagen , Masculino , Persona de Mediana Edad
5.
Z Kardiol ; 80(11): 687-94, 1991 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-1792811

RESUMEN

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.


Asunto(s)
Cardiotónicos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Piridazinas/uso terapéutico , Adulto , Anciano , Glicósidos Cardíacos/uso terapéutico , Cardiotónicos/efectos adversos , Diuréticos/uso terapéutico , Método Doble Ciego , Quimioterapia Combinada , Prueba de Esfuerzo/efectos de los fármacos , Femenino , Estudios de Seguimiento , Hemodinámica/efectos de los fármacos , Humanos , Cuidados a Largo Plazo , Masculino , Persona de Mediana Edad , Piridazinas/efectos adversos
6.
Z Gesamte Inn Med ; 46(13): 483-5, 1991 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-1962493

RESUMEN

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.


Asunto(s)
Embolia Pulmonar/prevención & control , Filtros de Vena Cava , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Flebografía
9.
Vasa Suppl ; 33: 202-3, 1991.
Artículo en Alemán | MEDLINE | ID: mdl-1788669

RESUMEN

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.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Ecoencefalografía/instrumentación , Procesamiento de Imagen Asistido por Computador/instrumentación , Ataque Isquémico Transitorio/diagnóstico por imagen , Adulto , Anciano , Arteria Carótida Interna/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Z Gesamte Inn Med ; 46(1-2): 49-51, 1991.
Artículo en Alemán | MEDLINE | ID: mdl-2038875

RESUMEN

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.


Asunto(s)
Isquemia Encefálica/complicaciones , Infarto Cerebral/complicaciones , Ataque Isquémico Transitorio/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico , Neumonía/etiología , Pronóstico , Embolia Pulmonar/etiología
11.
Z Gesamte Inn Med ; 45(22): 683-4, 1990 Nov 15.
Artículo en Alemán | MEDLINE | ID: mdl-2099029

RESUMEN

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.


Asunto(s)
Isquemia Encefálica/diagnóstico , Enfermedades de las Arterias Carótidas/diagnóstico , Angiografía Cerebral , Electroencefalografía , Ataque Isquémico Transitorio/diagnóstico , Adolescente , Adulto , Anciano , Arteria Carótida Interna/diagnóstico por imagen , Constricción Patológica/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico
12.
Z Gesamte Inn Med ; 45(20): 609-11, 1990 Oct 15.
Artículo en Alemán | MEDLINE | ID: mdl-2099578

RESUMEN

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.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Ecoencefalografía/métodos , Arteriosclerosis Intracraneal/diagnóstico por imagen , Ataque Isquémico Transitorio/diagnóstico por imagen , Adulto , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Isquemia Encefálica/fisiopatología , Enfermedades de las Arterias Carótidas/fisiopatología , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/fisiopatología , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/fisiopatología , Femenino , Humanos , Arteriosclerosis Intracraneal/fisiopatología , Ataque Isquémico Transitorio/fisiopatología , Masculino , Persona de Mediana Edad
13.
Hum Biol ; 62(3): 369-88, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2373507

RESUMEN

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.


Asunto(s)
Antropometría/instrumentación , Grosor de los Pliegues Cutáneos , Estudios de Evaluación como Asunto , Humanos , Reproducibilidad de los Resultados
15.
Z Med Lab Diagn ; 31(3): 181-4, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2368474

RESUMEN

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.


Asunto(s)
Infarto del Miocardio/sangre , Oligoelementos/sangre , Aldosterona/sangre , Cobre/sangre , Humanos , Hidrocortisona/sangre , Triyodotironina/sangre , Zinc/sangre
19.
Z Kardiol ; 77(4): 256-7, 1988 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-3388941

RESUMEN

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.


Asunto(s)
Electrocardiografía , Bloqueo Cardíaco/fisiopatología , Enfermedad de Lyme/fisiopatología , Miocarditis/fisiopatología , Adulto , Anticuerpos Antibacterianos/análisis , Nodo Atrioventricular/fisiopatología , Borrelia/inmunología , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad
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