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Biomedical subjects

D Schmidt

Publications and source records attributed to D Schmidt.

At least 19 recordsLinked to original sources
PubMed1979

Visualization of pi- and pi+ stopping density distributions in one and two dimensions.

A technique suitable for mapping pi+/- stopping density distributions in patients or phantoms is described. As a position sensitive detector a multiwire proportional chamber with a slit or a hole collimator in front was applied. Results using a water and a Rando phantom are presented for various momenta and momentum band widths of the pi+/- beam. To our knowledge the two-dimensional visualization of a pi- stopping density distribution was realized for the first time.

Elementary Particles↗
PubMed1979

Latent, manifest latent, and congenital nystagmus.

Manifest latent nystagmus (MLN) was identified in 31 patients by accurate eye movement records. All the patients had horizontal tropias, and the nystagmus fast phases were always in the direction of viewing eye. The slow phases of MLN are decreasing-velocity exponentials while those of the jerk form of congenital nystagmus (CN) are increasing velocity exponentials. Several subjects who were believed to have latent nystagmus (LN) on clinical examination had small amplitude nystagmus evident by eye movement recording with both eyes open: these were actually cases of MLN. Many patients with MLN are misdiagnosed as having CN. An explanation for MLN and LN is provided based on confusion of egocentric directions between monocular and binocular viewing conditions.

Adolescent↗
PubMed1979

Circulatory pattern and duration of action of naloxone in dogs with and without opioid pretreatment.

We investigated the circulatory pattern of naloxone reversal after high-dose fentanyl infusion in dogs. Within 1 min there was a sudden decrease in total peripheral resistance with a concomitant increase in stroke volume index. All other parameters changed back in direction of pre-fentanyl values in various degrees with peak effects in about 3-7 min. The persistency of reversal was different for individual parameters, but 20 min after injection of naloxone almost all changes induced by antagonisation of narcotic activity had returned to pre naloxone levels. In a control series with animals not pretreated with opioid, naloxone was shown to have no specific pharmacologic action of its own.

Animals↗
PubMed1979

[The haemodynamic effects of dobutamine and dopamine in patients with coronary artery disease. A study performed under general anaesthesia (author's transl)].

The haemodynamic effects of dobutamine (2 microgram/kg . min and 4 microgram/kg . min) and dopamine (4 microgram/kg . min and 8 microgram/kg . min) were studied in 17 patients with coronary artery disease prior to coronary bypass surgery. The study was performed under general anaesthesia (modified neurolept analgesia) and controlled ventilation. Dopamine improved cardiac index significantly, increased mean aortic pressure slightly while heart rate and total peripheral resistance remained unchanged. Dobutamine failed to increase cardiac and stroke index significantly, but increased mean aortic pressure distinctly due to an elevated total peripheral resistance. Both catecholamines increased left ventricular filling and mean pulmonary artery pressure. The HR x ASP-product which is closely related to left ventricular oxygen consumption was found to be augmented to a greater extent during dobutamine. For the above reasons dopamine should be favoured for increasing cardiac output in patients undergoing aortocoronary bypass surgery. Our study does not confirm earlier results which have shown dobutamine to be the preferable catecholamine. The possible reasons for this discrepancy are discussed.

Adult↗
PubMed1979

Certification of medical librarians, 1949--1977 statistical analysis.

The Medical Library Association's Code for Training and Certification of Medical Librarians was in effect from 1949 to August 1977, a period during which 3,216 individuals were certified. Statistics on each type of certificate granted each year are provided. Because 54.5% of those granted certification were awarded it in the last three-year, two-month period of the code's existence, these applications are reviewed in greater detail. Statistics on each type of certificate granted each year are provided. Because 54.5% of those granted certification were awarded it in the last three-year, two-month period of the code's existence, these applications are reviewed in greater detail. Statistics on MLA membership, sex, residence, library school, and method of meeting requirements are detailed. Questions relating to certification under the code now in existence are raised.

Canada↗
PubMed1979

Saccadic velocity characteristics: intrinsic variability and fatigue.

Saccadic eye movements exhibit a characteristic peak velocity vs. amplitude relationship. As with all quantifications of biological function, there exists and associated intra- and intersubject variability of this relationship. This paper documents this variability and demonstrates both the absence of a predictable short-term "muscle fatigue" effect and the presence of a generalized "mental fatigue" (i.e. tiredness) effect.

Adolescent↗
PubMed1979

[High doses of thiopental for therapy of post-ischaemic anoxia of the brain. A case report (author's transl)].

The case of a 7-year-old child is presented, who suffered circulatory arrest during induction of anaesthesia for surgery for a posterior fossa tumour. A brain ischaemia lasting 6 minutes duration had to be assumed. After restoration of circulation, 825 mg ethiopenta were administered in order to ameliorate a possible post-ischaemic anoxia of the brain according to a protocol by Safar [18]. 11 hours after circulatory arrest the child awoke. Except for a more pronounced left sided hemiparesis and paresis of the left n. abducens no additional neurological deficit was observed compared to the neurological status before induction of anaesthesia.

Anesthesia↗
PubMed1979

[Influence of starvation on the heart rate of rabbits].

The ECG was recorded in rabbits during EEG-controlled slow wave sleep and during food conditioning sessions. A 2-day food deprivation caused a significant slowing of mean heart rate during sleep. The heart rate increased in hungry animals waiting for food (food expectancy), but did not reach the values of saturated sleeping animals.

Animals↗
PubMed1979

[Animal experiments to study placental passage of Sombrevin and Hexobarbital and their concentrations in various foetal organ systems (author's transl)].

Studies were conducted into 55 rabbits and their 327 foetuses to measure the two intravenously applied anaesthetics, Sombrevin and Hexobarbital, for their passage through the placenta and for the concentrations which eventually settle in various organ systems of the foetuses. Fast placental passage, but in different concentrations, was established for either anaesthetic. Sombrevin was found to reach the foetal organism only in low quantity and for short-time retention, whereas Hexobarbital passed the placental barrier in much higher concentration to stay detectably for a longer period of time in the foetal blood. While Sombrevin was not recordable from foetal organs, its intraplacental buildup reached higher concentrations. Relatively high concentrations of Hexobarbital were recordable from both the placenta and vital foetal organs. The conclusions so far derived from those animal experiments seem to suggest a superiority of Sombrevin over Hexobarbital and regard to applicability to obstetric anaesthesia.

Animals↗
PubMed1979

[Blood pressures in gestosis patients under general anaesthesia following hypotensive treatment (author's transl)].

A retrospective evaluation was made of the blood pressures of 131 patients with hypertensive late gestosis who had undergone caesarean section for maternal or foetal indications, between 1971 and 1977. Rauwolfia preparations should be avoided in both long-term and acute hypotensive treatment of late gestosis patients not only for their unfavourable impact upon circulation at large, but also for their cumulative effects in terms of drastic depression of blood pressure in case of anaesthesia necessary for whatever reason. Acute hypotensive-sedative treatment should be discontinued and resumed, only if necessary, not until anaesthesia is over following surgical termination of pregnancy. Imminent eclamptic fit would be the only exception acceptable. Anaesthesia should be induced, using the base anesthetic propanidid which worked extremely well in terms of circulatory stabilisation. It is obviously superior to barbiturates in that particular respect.

Anesthesia, General↗
PubMed1979

[Cerebromeningeal fibroxanthoma. A case report].

This is a report on an almost seven-year-old girl with a histologically evident fibroxanthoma of the leptomeninx and dura mater cerebri. To the authors' knowledge, this is the fifth case of an intracranial fibroxanthoma reported in the literature. Histologically, the tumor consists of close-lying pleomorphic cells and giant multinuclear cells with vacuolate or homogeneous eosinophilic cytoplasm and fusiform cells occasionally arranged in meningeoma-like whorls. The experience gathered thus far shows that, so far as intracranial fibroxanthomata are concerned, predictions or conclusions regarding the course of disease and the probability of recovery should be made with reservation only.

Age Factors↗
PubMed1978

[Idiopathic blepharospasm. Clinical and electrophysiological investigations in 27 patients (author's transl)].

Idiopathic blepharospasm is reexamined and the differential diagnosis discussed on the basis of the signs and symptoms of 27 unpublished cases. As in tardive dyskinesia, middle-aged and elderly women are mostly affected. Contrary to general opinion, spontaneous improvement occurred in about one-fifth of the patients. The habituation of the orbicularis oculi reflexes (investigated electromyographically) was diminished in 52% of the patients. These and other symptoms indicate an organic cerebral lesion as the main cause of the disease. Similarities existing between blepharospasm and torticollis spasticus are discussed.

Basal Ganglia Diseases↗