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Biomedical subjects

P Schmidt

Publications and source records attributed to P Schmidt.

At least 199 records · Page 11Linked to original sources
PubMed1990

Determination of dose distribution of cosmic radiation behind different shielding thicknesses.

Investigations are described for the determination of dose distributions of cosmic radiation behind different shielding thicknesses. For this purpose, ultra-thin thermoluminescent detectors on a base of CaF2-polytetrafluorethylene (PTFE) were prepared and arranged in a stack at the outer wall of the biosatellite Cosmos 1887. During the 13 days of flight in a near-Earth orbit, the detectors were exposed to the unshielded cosmic radiation. After the flight, the dose distribution in the stack was determined by successive evaluations of the CaF2-PTFE discs. In the upper layers of the detector arrangement, dose values up to 100 Gy were observed. The strong decrease of the dose within a few mm demonstrates that weak particle radiation is dominant in the radiation field under investigation.

Calcium Fluoride↗
PubMed1990

Chicken egg antibodies for prophylaxis and therapy of infectious intestinal diseases. III. In vivo tenacity test in piglets with artificial jejunal fistula.

Large quantities of specific egg antibodies can be produced with little effort by immunization of laying hens. Several antibody containing egg preparations were subjected to a tenacity test against digestive activity taking piglets with artificial jejunum fistulas as a model. Even with high doses of orally administered yolk lyophilisate no antibody activity could be found in the distal jejunum. The additional feeding of egg white, however, showed a significant protective effect on the yolks antibodies during the digestive act. No difference between egg white of immunized hens and egg white of unimmunized hens could be detected. Buffering the acidic gastric environment with sodium bicarbonate increased the antibody activity in the intestine by an average of 40%. Eggs administered in hot (70 degrees C) beef stock had higher antibody titers than eggs that were boiled for 4 minutes. Tenacity in antibodies fed in pellets was significantly lower than in powdered feed.

Animals↗
PubMed1990

The remitting atypical psychoses: clinical and nosologic considerations.

There exists in the literature a group of nonorganic psychoses which appear to have no obvious relationship to either schizophrenia or affective illness. Diagnostic terminology to classify these atypical psychoses has been varied, although features in common can be identified. For example, they often are associated with antecedent personality problems, acute onset, florid and mixed symptomatology, brief duration, and full remission with a return to premorbid level of functioning. Case material reflecting these types of psychoses is presented here, and is discussed with reference to the nosologic status of these atypical psychoses.

Adult↗
PubMed1990

[The differential diagnosis of spinal cord malformations in cattle].

Hereditary developmental disorders of the CNS, especially spinal cord, are of increasing importance in the bovine species. Therefore, congenital spinal malformations of non-hereditary origin have to be ruled out by carefully directed neuromorphological procedures. The two cases of malformation of the spinal cord reported were not accompanied by vertebral defects: The first one represents a complete diplomyelia of the caudal lumbo-sacral medulla in an 18 months old Brown Swiss heifer, the second one a circumscribed hydromyelia of the fifth lumbal segment, based on an incomplete dysraphic defect, in a 4 months old male German Simmental calf. Problems of diagnostic measures and of terminology, concerning differentiation between diplomyelia and diastematomyelia, were discussed in detail.

Animals↗
PubMed1990

[Frontal sinus injuries: apropos of 67 cases].

The authors report their experience in the treatment of frontal sinus fractures, between 1979 and 1987, about 67 cases. 52% of these trauma involve alone, the anterior and/or posterior wall of the frontal sinus, with or without cerebrospinal fluid rhinorrhea. The sinus surgery was composed of cranialization in 20 cases (30%) and open reduction with reconstruction, with or without tube to stent the nasofrontal duct, in 30 cases (48%). Two points appear to them, essential to guide the treatment, osteomeningeal tear and naso-frontal duct injury.

Adolescent↗
PubMed1990

Female DWI-delinquency and chronic alcoholism in Düsseldorf.

The blood sample records of all 1,231 blood samples of female DWI-offenders submitted to the Düsseldorf Institute of Forensic Medicine in 1986/87 were analysed for date and time arrest, age, additional drug intake. BAC and results of medical examination. The data obtained were compared to a randomly selected male comparison group and to the situation in the sixties. The proportion of women arrested for impaired driving has increased from 1.75% in the sixties to 7.5% in 1986/87 (factor 4.3), the percentage of highly intoxicated women (BAC above 2.5 g/l) from 0.07% to 0.55% (factor 7.9). Current female DWI behavior is quite similar to male with both groups mainly comprising highly intoxicated young subjects apprehended on the days of the weekend in the hours around midnight. Women more often admit additional drug intake with benzodiazepine abuse representing a major problem. As concluded from time of arrest, discrepancy between BAC and degree of drunkeness and blood methanol levels about 60% of the women with a BAC above 2.5 g/l have to be classified as chronic alcoholics. As a consequence female alcoholics are significantly overrepresented in female DWI-delinquency.

Accidents, Traffic↗
PubMed1990

[Injuries of the frontal sinus].

The authors report their experience in the treatment of frontal sinus fractures, between 1979 and 1987, about 67 cases. --52% of these trauma involve alone, the anterior and/or posterior wall of the frontal sinus, with or without cerebrospinal fluid rhinorrhea; --the sinus surgery was composed of cranialization in 20 cases (30%) and open reduction with reconstruction, with or without tube to stent the nasofrontal duct, in 30 cases (48%). Two points appear to them, essential to guide the treatment: --osteomeningeal tear, --naso-frontal duct injury.

Adolescent↗
PubMed1990

[Psychosocial factors of preserving health? Prospective studies of breast cancer, bronchial cancer and fibrocystic mastopathy].

Do psychosocial factors affect the development of health? 156 patients were interviewed and tested before a breast biopsy or before the initial medical treatment of lung cancer. Multiple regressions examined the influence of age, diagnosis (tumor stage) and different psychosocial parameters as dependent variables the development of health after 2 or 5 years as independent variables. The breastbiopsy-group (n = 52) shows five psychological variables being effective in a positive (health promoting) manner: autonomy, emotional outlet, expression of one's needs, family support, lack of life stress. In lung cancer (n = 104) the development of health 2 years after diagnosis is only influenced by the type of tumor (small cell versus non small cell) and by the initial tumor stage. A structuralequation model (LISREL) shows for the first 3 months of illness that almost exclusively biological variables have an influence on psychological variables. Despite this family dynamics had a moderate effect on the patient's general wellbeing (Karnoffsky-Index).

Adult↗
PubMed1989

A selection for mutants of the RNA polymerase III transcription apparatus: PCF1 stimulates transcription of tRNA and 5S RNA genes.

A genetic approach has been developed to study transcription by RNA polymerase III. A pair of Schizosaccharomyces pombe nonsense suppressor tRNA genes were arranged in tandem such that expression of the downstream (supS1) tRNA suppressor was dependent upon transcription initiated by the internal promoter of the upstream (sup9-e) gene. Dominant mutant strains of Saccharomyces cerevisiae were isolated that suppress in trans the effect of an A block promoter mutation (A19) in the sup9-e gene and restore supS1 suppressor activity. Fifteen mutant strains, eight of which were independently isolated, all have elevated steady-state levels of sup9-e A19 RNA consistent with an increase in gene transcription. Extracts of a strain carrying the dominant mutant gene, PCF1, show a general 6-fold stimulation in transcription of mutant (A19) and wild-type tRNA genes and increase 5S gene transcription 4-fold compared with extracts from a wild-type strain. A transcription factor exclusion assay was used to show that the PCF1 mutation affects two distinct stages in transcription: one prior to and one after stable complex formation; and that these effects are mediated by a component of the stable complex. Further evidence of an effect during complex assembly was obtained in a time-course experiment that showed a shortened lag phase in the PCF1 extract. The results indicate that PCF1 is either a component of the stable complex or a positive regulator of its activity.

Base Sequence↗
PubMed1989

[How often and for what symptoms would parents consult child heath services?].

Author prepared and processed 1500 computerised questionnaires in which primary-school children' parents were asked about their knowledge of symptoms of children- diseases and habits: "how to consult with physicians". The questionnaire was divided 3 parts: in the first one general questions and some problem in connection with high temperature, in the second one about symptoms, and in the third group pains were mentioned located in organs and different body-parts of children. The majority of parents accepted these questions and gave good answers and prepared some additional suggestions. Other group of parents having very bad habits relation to symptoms, and "how to consult with doctors and call duty-system". Author emphasized the very important role of data processing system for the further health organisation and health education.

Child↗
PubMed1989

[Successful clonidine treatment of restless leg syndrome in chronic kidney insufficiency].

Restless legs syndrome is a common and sometimes incapacitating disorder in chronic uraemic patients. While therapeutic concepts have so far been disappointing, there have been recent reports on the favourable effect of clonidine in non-uraemic patients with symptoms of restless legs syndrome. Therefore, a double-blind study was conducted in 20 patients with chronic renal failure (11 conservatively treated, 9 on RDT) and symptoms of restless legs. 10 patients were treated with 0.075 mg clonidine twice daily and 10 received placebo. The patients were investigated 3 days after starting therapy. - In the clonidine-treated group complete relief of symptoms was noted in 8 out of 10 patients, a striking alleviation in one, while in one further patient the symptoms remained unchanged. In contrast, only one of 10 patients in the placebo group had a mild alleviation of symptoms. Blood pressure did not differ significantly in the two groups. The data show that low-dose clonidine administration is a very effective approach in the treatment of the restless legs syndrome in chronic uraemic patients.

Adult↗
PubMed1989

Development of an ELISA for detection of an organophosphorus compound using monoclonal antibodies.

This paper describes a specific and highly sensitive ELISA system using monoclonal antibodies in order to assay an organophosphorus compound. The soman derivative methyl phosphonic acid, p-aminophenyl 1,2,2,-trimethyl-propyl diester (MATP) served as model substance. In order to obtain antibody-producing hybridomas BALB/c mice were immunized with MATP linked onto human serum albumin (HSA). The spleen cells of immunized mice were fused with syngenic plasmacytomas of the non-producer-line X63Ag8.653 with the aid of polyethylene glycol. To eliminate undesirable cross-reaction, common screening procedures were modified by directly coating the ELISA plates with hapten. Five out of 15 positive cell-lines were cloned by limiting dilution and further propagated. The respective immunoglobulin class and subclass of the obtained monoclonal antibodies was determined. Four of which were identified as IgG1, the other as IgG2a. After enrichment of antibodies in ascites and their isolation by protein A-sepharose, the affinity of various monoclonal antibodies was estimated in competitive inhibition enzyme immunoassay (CIEIA) by measuring the IC50 rates of free MATP. The rates were found to lie between 2.5 x 10(-6) mol/l and 4.3 x 10(-4) mol/l MATP. The IC10 rate for detectable MATP concentration was 5.4 x 10(-7) mol/l MATP. Test duration was 280 min. The reactivity of the monoclonal antibodies with structurally related substances was used to check their specificity. Cross-reaction turned out to be negative. In order to develop a direct competitive ELISA, MATP was linked to horse radish peroxidase (HRPO) by adding a spacer. This helped to reduce total duration to 40 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Improved low energy defibrillation efficacy in man with the use of a biphasic truncated exponential waveform.

The standard implantable defibrillator waveform is a truncated exponential of approximately 6 msec duration. This study compares the defibrillation efficacy of a standard monophasic truncated exponential to a biphasic 12 msec truncated exponential waveform in 21 patients undergoing automatic implantable cardioverter defibrillator (AICD) surgery. For the biphasic waveform, the polarity was reversed and remaining capacitor voltage was attenuated by 75% after 6 msec. Two hundred thirty episodes of VF were induced with 115 "matched pairs" of monophasic and biphasic waveforms of identical initial capacitor voltages given over a range from 70 to 600 V (0.35 to 25.7 joules). The biphasic waveform was superior to the monophasic waveform (p less than 0.006), especially for "low energy" defibrillation. For initial voltages less than 200 V, the percent successful defibrillation was 28% for the monophasic waveform versus 64% for the biphasic waveform and from 200 to 290 V (energies less than 6.4 joules) it was 45% versus 69%. There was no difference in the two waveforms in time to the first QRS complex or in the blood pressure following defibrillation. This study shows that a 12 msec biphasic truncated exponential is superior to a 6 msec monophasic waveform for defibrillation in man, especially at energies less than 6.4 joules. The waveform can be achieved in an implanted device without any increase in capacitor size or in battery energy consumption.

Electric Countershock↗
PubMed1989

Long-term outcome with the automatic implantable cardioverter-defibrillator.

The automatic implantable cardioverter-defibrillator was implanted in 270 patients because of life-threatening arrhythmias over a 7 year period. There was a history of sustained ventricular tachycardia or fibrillation, or both, in 96% of these patients, 80% had one or more prior cardiac arrests and 78% had coronary artery disease as their underlying diagnosis. The average ejection fraction was 34%, and 96% of these patients had had an average of 3.4 antiarrhythmic drug failures per patient before defibrillator implantation. There were four perioperative deaths and eight patients had generator infection or generator erosion, or both, during the perioperative period or during long-term follow-up. Concomitant antiarrhythmic drug therapy was given to 69% of patients. Shocks from the device were given to 58% of patients. and 20% received "problematic" shocks. The device was removed from 16 patients during long-term follow-up for a variety of reasons. There were 7 sudden cardiac deaths and 30 nonsudden cardiac deaths, 18 of which were secondary to congestive heart failure. The actuarial incidence of sudden death, total cardiac death and total mortality from all causes was 1%, 7% and 8%, respectively, at 1 year, and 4%, 24% and 26% at 5 years. The automatic implantable cardioverter-defibrillator nearly eliminates sudden death over a long-term follow-up period in a high risk group of patients. It has an acceptable rate of complications or problems, or both, and most late deaths in these patients are nonsudden and of cardiovascular origin.

Death, Sudden↗