Search PubMed⌕ Search

Biomedical subjects

U Meier

Publications and source records attributed to U Meier.

At least 109 records · Page 6Linked to original sources
PubMed1987

[Computerized tomography and infusion test as a simultaneous study method in post-traumatic hydrocephalus].

The cerebral compression of a patient with posttraumatic hydrocephalus was measured intraventricularly, and an intrathecas infusion test was made simultaneously with computed tomography. Substractive computed tomography pictures show that continuously increasing volume does not imply uniform enlargement of the ventricular system, the cornua of the lateral ventricles in particular exhibiting a frontal increase in size.

Adult↗
PubMed1987

[Penetrating craniocerebral injury].

Through a ten-year period, treatment was applied to 145 patients for open craniocerebral injuries in the calottal region. Mortality amounted to 35 per cent and postoperative infections to 16 per cent. Early or, in cases of intracranial invasive growths, immediate surgery with purpose-oriented osteoplastic trepanation is the optional method.

Adolescent↗
PubMed1987

[Instrumentation for hollow screw osteosynthesis of basal dens axis fractures].

The trend in the treatment of odontoid bone fractures is characterized by progressive application of operative methods. Special instruments for the fixation of odontoid bone was developed. Due to the ventral extraoral approach odontoid bone is possible to fix temporary with two rigid Kirschner wires by these hollow screws drilled from the ventral lower edge of the second vertebral body through the fracture in the odontoid bone. By using this method the operative procedure is much more safety as well as the x-ray exposure of the patient and of the operating team is reduced.

Axis, Cervical Vertebra↗
PubMed1987

[The intrathecal infusion test in the study of craniospinal cerebrospinal fluid dynamics. A new assessment procedure].

A new mathematical method is presented for calculation of cerebrospinal fluid (CSF) parameters. Intrathecal lumbal infusion test with constant flow technique was used. Resistance to CSF outflow R(p) and compliance C(p) are computed by continuous comparing the change of pressure response dp/dt during infusion and--dp/dt after infusion. Using of this method, it is not necessary to determine the pressure plateau at the steady-state between artificial volume loading and the rate of CSF outflow. With that we were able to minimize the physical load on the patient. The expressiveness of investigation is increased by printing graphs of pressure-dependent resistance CSF outflow and compliance.

Cerebrospinal Fluid↗
PubMed1986

[Concentration and memory impairment in the later postoperative phase].

Of the different psychic function disturbances which may occur during the postnarcotic phase, those showing symptom complexes with sensory, neurotic-emotional or psychotic reactions mostly diminish within some hours or a few days. On the other hand, a great many patients suffer from individual mental problems of which concentration and memory weaknesses are the main characteristics, sometimes outlasting the surgical operation by a number of weeks or even months. The results of a preliminary examination of 520 patients, recently released from surgical departments, confirmed that 30% suffered from prolonged memory disturbances. Of a control group of patients treated with local anesthesia only 6% of 69 persons questioned had been aware of such symptoms. In the consecutive analysis of 90 surgical patients, making use of psychometric test methods such as digit span, learn- and memory test (German abbreviation LGT1) and concentration test d2, no reduction of memory capacity could be ascertained. An additional questioning of these patients about subjectively experienced disturbances, in comparison with the preliminary examination, resulted in approximately identical statements. The aetiology of subjectively experienced impairment of memory and concentration during the later postoperative phase appears to be still insufficiently clarified, for which psychogenic factors must be taken in consideration.

Adult↗
PubMed1985

Genetic location of genes encoding enterobacterial common antigen.

A new rff mutation (rff-726) of Escherichia coli is described which affects the biosynthesis of the enterobacterial common antigen. This mutation was detected in an rfe-defective strain. A Tn10 insertion near the rfe locus was isolated to facilitate further mapping. Both mutations rfe and rff were mapped by transduction with bacteriophage P1, giving the gene order ilv rfe rff uvrD metE. The F' factor F14 was able to complement both mutations rfe and rff, whereas the F' factor F16 could complement the rfe but not the rff mutation. The rff mutation did not affect the biosynthesis of N-acetyl-D-mannosaminuronic acid, as the previously described rff mutations in Salmonella typhimurium do (H. C. Lew, H. Nikaido, and P. H. Mäkelä, J. Bacteriol. 136:227-233, 1978), and also did not affect the biosynthesis of other enterobacterial common antigen components; however, the biosynthesis of the complete enterobacterial common antigen molecule was blocked.

Antigens, Bacterial↗
PubMed1984

[Fundus asymmetry--supertraction of the papilla and posterior sclera staphyloma--as a source of error in the calculation of intraocular lenses].

The evaluation of 404 consecutively implanted posterior-chamber intraocular lenses after extra-capsular cataract extraction revealed a mean post-operative refractive error of + 0.52 diopters with a standard deviation of +/- 1.27 diopters. Four calculations attracted attention because of their unusually high refractive error of + 3.4 diopters. A post-operative refractive balance excluded measurement or calculation errors. On the other hand, repeated axial length measurements on these four eyes showed a very high mean variation of 3.27 mm. This high variation can be correlated to such typical elevation changes of the central fundus as a tilted disc or posterior staphyloma. High axial length measurements which do not correspond to appropriate amounts of axial myopia should be handled carefully to avoid high amounts of hyperopia following intraocular implantation.

Fundus Oculi↗
PubMed1982

[Computer tomographic measuring procedure in generalized brain edema after craniocerebral trauma].

Computer tomography enables for the first time the direct demonstration of the consequences of a craniocerebral trauma. In the computer tomogram, the cerebral oedema is dominating as an area of reduced density (hypodense region). Three different measuring techniques are compared and their application in 43 craniocerebral traumata discussed. Among the measuring methods employed, the area index shows the greatest diagnostic reliability in the computer-tomographic findings of a posttraumatic cerebral oedema. The partial volume analysis without application of a contrast medium is of little use for computer-tomographic clearing of the question of a generalised cerebral oedema after SHT while the density index is only suitable in conjunction with additional parameters.

Adolescent↗
PubMed1981

The epididymis and its development in ratite birds (ostrich, emu, rhea).

The epididymis of ratitae is subdivided into a main part and a appendix epididymidis. The appendix epididymidis consists of the ductus aberrans and ductuli aberrantes. The ductus aberrans is the cranial continuation of the ductus epididymidis. The appendix epididymidis is cranially attached to the adrenal gland. In the main part of the epididymis the largest part of the rete testis is found. The rete testis is composed of an intratesticular rete (also named tubuli recti), and intracapsular rete (with a longitudinal cistern and a true rete), and an extratesticular rete (predominantly consisting of approximately 20 longitudinal channels). The rete testis develops most likely embryonally from buds of the glomerular capsules of the mesonephros. The ductuli efferentes proximales also from these capsules, while the ductuli efferentes distales develop from the proximal and distal tubules and intermediate-segments of the mesonephros. The ductus epididymidis originates from the Wolffian duct and meanders dorsolaterally through the epididymis.

Animals↗
PubMed1980

[Dosage related effect of fenoterol on fetal hemoglobin oxygen affinity (author's transl)].

Fenoterol induced displacements of the fetal oxygen dissociation curve were investigated in animal experiments by determining the oxygen halfsaturation pressure (P 50). At term pregnant rabbits were infused intravenously over 3 hours with an increasing Fenoterol dosis (10 to 30 microgram/kg/min) up to a dosis level which produced complete labour inhibition. By cesarean section fetal aortic blood was collected and the oxygen halfsaturation pressure (P 50) was determined as described by Lichtman et al. (14). All P 50 values were corrected to so-called standard conditions (pH: 7.4; PCO2: 40 mmHg; t: 37 degrees C). Likewise, in a second series P 50 values were measured in newborn rabbits which received Fenoterol subcutaneously as a single shot injection. In the first series standardized P 50 significantly fell from 20.9 to 15.0 mmHg and in the second series it fell from 20.9 to 14.4 mmHg. This raised oxygen hemoglobin affinity, i.e. leftward shift of the fetal oxygen dissociation curve, is probably due to a Fenoterol induced diminution of the red cell 2.3-DPG concentration. In all cases of severe fetal hypoxia a beneficial effect on O2-transport is discussed whereas at normoxia or mild hypoxia a rightward shift of the oxygen dissociation curve would be more favourable.

Animals↗
PubMed1979

[Examinations on the pathomechanism of severe cardio-pulmonary hazards under i.v. tocolytic treatment with beta-adrenergic drugs (author's transl)].

Lungs edemas in five pregnant women under i.v. tocolytic treatment with betaadrenergic drugs between the 28.--33. week of gestation are reported. Additionally, in all cases Betamethasone was given to prevent fetal lungs dysmaturity. Within less than 72 hours the occurrence of lungs edema was observed when both drugs were given simultaneously. These findings are in agreement with those of other authors, who observed similar symptoms in as well clinically healthy pregnant women under the same therapy. As the underlying pathomechanism the coincidence of the following factors are discussed: 1. An increased pressure in the pulmonary circulatory system as found in current, not yet published heart catheter investigations. 2. A reduced colloidosmotic pressure caused by Beta-methasone.

Adrenergic beta-Agonists↗
PubMed1978

Interrelation between Bohr and temperature effects on the oxygen dissociation curve in men and women.

For both sexes (7 males, 7 females) the fixed acid Bohr coefficient BCFA (delta PO2/deltapH) and the temperature coefficient TC (deltalogPO2/deltaT) were investigated in whole blood as function of oxygen saturation (SO2). BCFA which yielded maxima at midsaturation were generally lower at increased temperature (41 degrees C) and in females. Values for 50% SO2 amount to: -0.46 +/- 0.04 SD (males) and -0.37 +/- 0.06 (females) at 37 degrees C, -0.38 +/- 0.09 (MALes) and -0.31 +/- 0.04 (females) at 41 degrees C. TC, too, was generally lower in females, decreased in both sexes at falling pH, but showed no O2-saturation dependency. Mean values were 0.024 +/- 0.008 (males) and 0.017 +/- 0.003 (females) at pH 7.4, 0.019 +/- 0.008 (males) and 0.012 +/- 0.006 (females) at pH 7.2. Sex differences of both TC and BC could also be confirmed in additional experiments. While the interrelation of BC and TC and the variable saturation effect on the coefficients may be referred to known theories about ionization heats of oxylabile groups and nonuniform reactions of the single Hb4(O2)n fractions, respectively, no clear explanation was found for the sex influence.

Adult↗
PubMed1976

Some evidence for aldosterone action on 2,3-diphosphoglycerate level in human red cells.

In healthy male subjects aldosterone excretion and plasma renin activity were reduced by a 4-6 hr head-out immersion in thermoindifferent water baths (35.5 +/- 0.1 degrees C). The red cell 2,3-diphosphoglycerate (DPG) concentration before and throughout immersion period was positively correlated both with aldosterone excretion in 2 hr pooled urine (r = +0.69; 2 p less than 0.001) and with renin activity (r = + 0.54; 2p less than 0.001) despite a concomitant increase of cubital venous pH and inorganic phosphate concentration. These findings furnish evidence for a regulatory role of aldosterone in DPG metabolism, possibily by a direct influence on red cell glycolysis.

Adult↗
PubMed1975

Effects of a multi-hour immersion with intermittent exercise on urinary excretion and tilt table tolerance in athletes and nonathletes.

The circulatory and diuretic responses of athletes and non-athletes to 6-h water i-mersion with intermittent swimming exercise (series I) as well as to 8-h inactive immersions (series II) were studied. With simultaneous intermittent exercise, the normally arising diuresis during a water bath was strongly suppressed in athletes and even abolished in nonathletes. In subsequent tilt table tests, 3 of 11 (27.3%) athletes of series I and 3 of 4 (75%) of series II collapsed, whereas all nonathletes tolerated the vertical position without any subjective complaints. By use of the so-called "orthostatic index" (4) the later group, however, was also shown to yield a substantially better orthostatic stability in series I than in series II. The protective effect of intermittent physical activity for simulation of the weightless state can possibly be explained by assuming a less-reduced plasma volume via a diminished urinary excretion.

Adaptation, Physiological↗