Search PubMed⌕ Search

Biomedical subjects

I Schmidt

Publications and source records attributed to I Schmidt.

At least 127 records · Page 7Linked to original sources
PubMed1984

Results of interlocking wire trochanteric reattachment and technique refinements to prevent complications following total hip arthroplasty.

In 3.2% of 712 procedures performed in 668 hips after May 1, 1976, separation and migration of the trochanteric fragment occurred after total hip arthroplasty (THA) through a transtrochanteric approach and an interlocking cruciate two-wire technique of reattachment. Of these hips, 23 trochanters showed separation, and in eight the Trendelenburg test was positive. The abductor weakness was correlated with the amount of separation, especially if it exceeded 2 cm. Trochanteric separation was attributed to technical deficiencies, including a small trochanteric fragment, wire placed around the lesser trochanter, and/or a loose wire loop. Improved technique reduced the separation and migration rate from 4.5% to 2.3% following primary surgery. Trochanteric advancement with impaction against the vastus ridge and repair of the vastus lateralis were major determinants in reducing the migration rate of those that did not unite and were responsible for improved gait in this second series. However, the failure rate remained at 7% following reoperations for failed THA. As a result, a more secure three-wire technique with two vertical wires has been used in 36 revision operations since July 1981 with no incidence of migration.

Femur↗
PubMed1982

Negative and positive feedback of central nervous system temperature in thermoregulation of pigeons.

Experimental alterations of spinal cord and hypothalamic temperature affecting behavioral and autonomic cold defense were investigated in pigeons under external cold load with access to instrumental heat reinforcement. Warming and cooling spinal cord resulted in negative-feedback effects on both instrumental and autonomic cold defense. Hypothalamic warming produced similar negative-feedback effects, whereas hypothalamic cooling produced either no effect or positive-feedback effects on both kinds of cold defense. As determined in previous studies, hypothalamic temperature displacements under heat-load conditions produced only negative-feedback effects on instrumental heat defense. However, only positive-feedback effects were observed on autonomic heat defense by panting. The diverse response patterns of autonomic and behavioral thermoregulatory effectors to changing hypothalamic temperature under heat- and cold-load conditions could be quantitatively described by a mathematical model that takes into account 1) a greater Q10 for intrahypothalamic transmission of the cold signal input than of the warm signal input, and 2) different weights of extra- and intrahypothalamic temperature signal inputs for the control of different effectors.

Animals↗
PubMed1981

Contrast media-induced side effects on excitation and conduction of electrical activity in the heart on intracardiac application. Investigations in anaesthetized dogs.

In several series of experiments with intracardiac application in anaesthetized dogs, the following contrast media were tested for their adverse effects on excitation and conduction of electrical activity in the heart. Diatrizoate, lysine-diatrizoate, lysine-sodium-diatrizoate, ioxaglate, iopamidol, iodamide, ioxitalamate, ioglicinate and metrizamide. Blood pressure and, using the His' bundle-ECG technique, the parameters P0-P1 (heart rate), A1-H1 period (conduction time in the AV-node), and H1-V1 period (conduction time in the TAWARA branches) were measured. A statistical correlation exists between osmolarity and blood pressure (higher osmolarity causes a greater decrease in blood pressure), as well as between osmolality and decrease in heart rate (higher osmolarity causes a greater decrease in heart rate). The delay in conduction time in the AV-node correlates only with viscosity and sodium content (increased viscosity with increased sodium content delays the time of conduction). A tendency towards delay in conduction in the TAWARA branches could not be correlated to any one of the physico-chemical parameters studied.

Anesthesia, General↗
PubMed1979

Temperature changes of the hypothalamus and body core in ducks feeding in cold water.

Hypothalamic (Thy), spinal(Tsc) and colonic (Tc) temperatures were measured in Pekin ducks spontaneously dabbling for food in cold water (5 degrees C). In agreement with observations in the pigeon and the fowl Thy was found to be consistently lower by about 0.5 degrees C than the other core temperatures. The drop of Thy during dipping head and neck into the cold water was not substantially greater than that of Tsc, while both changed more than Tc. The measurements do not support the assumption that the hypothalamic region in the duck is exposed to substantially greater temperature fluctuations than other thermosensitive parts of the body core.

Animals↗
PubMed1979

[Operative treatment of deep vein thrombosis (author's transl)].

From 1973 to 1977 a total of 63 patients with thrombosis of the deep veins in leg and pelvis and in the V. cava inferior was treated by operative thrombectomy. Prior to the operation all patients were submitted to phlebography. The mean age of all was 52 years. One patient died from pulmonary embolism during thrombectomy, there was no further hospital mortality. Because of low mortality incidence and rarely postthrombotic complications we prefer the operative treatment of deep vein thrombosis. The preoperative cavography helps to avoid pulmonary embolism during thrombectomy.

Adolescent↗
PubMed1979

[Correspondence alterations due to tenomyotomy (author's transl)].

This report covers 310 patients with concomitant convergent strabismus and anomalous retinal correspondence. In 36 cases tenomyotomy alone was responsible for normalization of correspondence. This is best achieved in cases of bilateral converging strabismus without vertical divergence.

Adult↗
PubMed1979

[Preliminary pharmacokinetics of metoclopramide in humans. Plasma levels following a single oral and intravenous dose (author's transl)].

A quantitative thin-layer chromatographic method is discribed for the determination of metoclopramide in human plasma for the 40--320 ng/ml range. Similar plasma levels were observed after single oral dosing with capsules (5 X 11.62 mg metoclopramide X 2 HC'L X H2O) and i.v. injection (2 X 11.62 mg metoclopramide X 2 HCl X H2O). The shape of the plasma level curve after i.v. administration indicates the presence of an open two-compartment model for metoclopramide in humans. Following a very short distributive phase an elimination phase is observed with a half-life of 3--6 h over the period studied. The present data suggest that under the conditions employed in this study metoclopramide is bioavailable by only about 50%; a "first-pass" metabolism is indicated.

Administration, Oral↗
PubMed1978

Interactions of behavioral and autonomic thermoregulation in heat stressed pigeons.

The interactions of behavioral and autonomic thermoregulation in pigeons during ambient heat load were studied by simultaneous measurements of instrumental response rate for cold air reinforcement and respiratory rate. When providing sufficient reinforcement-magnitudes, deep body temperatures were stabilized, due to a linear increase of response rate with ambient loads from 40-60 degrees C, without involving an increase in respiratory heat dissipation. This was effected by maintaining the temporal mean of air temperature and consequently of all skin temperatures at a level independent from load temperature (Fig. 3). When the efficiency of instrumental thermoregulation was limited by reducing the reinforcement-magnitude, not only the instrumental response rate increased, but in addition body temperatures and subsequently respiratory rate rose with the thermal load. Thus a positive correlation between body temperatures and response rate and a simultaneous increase of autonomic heat defence activities characterize incomplete behavioral thermoregulation. The instrumental response rate rapidly followed changes of external load temperature without preceding changes of core temperatures or skin temperatures at well feathered areas (Fig. 6). These findings suggest that the input signal controlling instrumental thermoregulatory behavior is related to the rate of change of temperatures at exposed areas of the body shell, whereas the autonomic heat defence response follows the steady displacements of body temperatures. This points to an important difference between the input signals controlling behavioral and autonomic heat defence in the pigeon.

Animals↗
PubMed1978

[Selection and characterization of Penicillium cyclopium mutants with altered developmental program].

After treatment with NNMG, NaNO2 or UV-light of conidiospores of Penicillium cyclopium strain SM 72 variant strains (mutants) with altered developmental programme were selected. Additionally from a methionine-auxotrophic mutant of P. cyclopium prototrophic revertants were prepared. Investigation of the alkaloid metabolism and other idiophase processes has shown that these mutant strains can be divided into two groups (cf. table 1): a) Mutants with a depression of all idiophase features. The defects of these strains presumably affect central regulatory processes which, as in strain rev-met 83a, can be reversed spontaneously by an one-step mechanism and b) mutants defective in certain parts of the idiophase programme only, demonstrating that there is a certain autonomy in regulation of the individual parts of the programme.

Alkaloids↗
PubMed1978

[Synthesis of human [11-leucine]minigastrin I--II. Purification of the synthetic tridecapeptide amide and isolation of a side-product (author's transl)].

The preparation of the pure 11-leucine analogue of human minigastrin I, a linear tridecapeptidaemide with full "gastrin activity", from the crude synthetic material obtained after deblocking of the overall protected tridecapeptide amide derivative by means of trifluoroacetic acid, is achieved by ion-exchange chromatography on DEAE-Sephadex A-25 and subsequent partition chromatography on Sephadex G-25. The isolation of a synthetic side-product and its identification as human [10-(Nin-tert-butyl-tryptophan),11-leucine]minigastrin I by means of spectroscopic (UV, fluorescence, 1H-NMR, MS), enzymatic and chromatographic methods is described. The pure tridecapeptide amides human [Leu11]minigastrin I and human [Trp(1'-But)10,Leu11]minigastrin I are isolated in overall yields of 37.4% and 4.6%, respectively (mol-% with regard to the overall protected tridecapeptide amide derivative).

Amides↗