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Biomedical subjects

A Schmidt

Publications and source records attributed to A Schmidt.

At least 739 records · Page 41Linked to original sources
PubMed1977

Prevention of 2-acetylaminofluorene-induced extrahepatic short-term effects by 3-methylcholanthrene.

It is well known that simultaneous application of polycyclic carcinogenic hydrocarbons, especially 3-methylcholanthrene (MC) inhibits or prevents tumorigenesis induced by carcinogenic aromatic amines or azo dyes. Short-term tests showed a mitogenic effect upon adrenal cortex 48 hours following a single dose of 2-acetylaminofluorene (AAF) among other carcinogenic substances. 6 mg/kg body weight given simultaneously prevent the proliferative response of the adrenals by AAF (60 mg/kg b.w.) in male Sprague-Dawley rats. These different effects can be assumed to depend on the production of carcinogenic derivatives or their non-production. Therefore, the positive adrenal reaction by other substances tested is probably also provoked by carcinogenic compounds. The lack of responsiveness by MC may reflect a fundamental change of AAF metabolism. The mode of action is unknown. Possible explanations are discussed.

2-Acetylaminofluorene↗
PubMed1977

The diagnosis of pancreatic cyst by endoscopic retrograde pancreatography and ultrasonic scanning.

Fourteen patients with verified pancreatic cysts were examined by both preoperative endoscopic retrograde pancreatography (ERP) and ultrasonic scanning. ERP showed filling of a cyst in 4 patients and raised suspicion of a cyst in 8. In two patients it was not possible to visualize the pancreatic duct. Ultrasonic scanning showed a cyst in 12 patients. There were two false negative ultrasonic diagnoses. These two were correctly diagnosed by ERP. Ultrasonically guided percutaneous puncture was carried out on 19 occasions in 8 patients. Cysts down to 2 cm in diameter were punctured without difficulty. There were no clinically significant complications due to the punctures. One patient was followed for 20 months without ultrasonically demonstrable recurrence of a large cyst aspirated, showing that definite therapy is possible by this method. Puncture can be used to verify the diagnosis and as treatment in patients where surgery is contraindicated.

Diagnosis, Differential↗
PubMed1977

Low dose heparin in major surgery: clinical relevance of plasma heparin concentrations.

56 patients undergoing elective major surgery received low dose heparin prophylaxis, 5,000 IU 2 h before surgery and every 8 h for 7 days. The patients were tested by the 125I-fibrinogen uptake test, which, if positive, was controlled by venography. The heparin concentrations were measured by the method of DENSON and BONNAR and by the chromogenic method of TEIEN et al. in blood samples drained immediately before and after surgery and on the 1st and 5th postoperative day 2 and 4h after the injection of heparin. The values were found higher when estimated by the method of DENSON and BONNAR than by the chromogenic method. Deep vein thrombosis (DVT) developed in 11 patients, and in 10 of them within the first 48 after the operative procedure, in 1 after 4 days. The preoperative values were not lower in the patients who developed DVT, and the heparin concentrations found on the 1st and 5th postoperative day were at the same level as in those who did not develop DVT.

Adult↗
PubMed1977

[The cialit-conserved trachea homograft (author's transl)].

After all techniques for reconstruction of tracheal segments with trachea-homografts, known from the literature, have failed to show satisfactory functional results, we have carried out further experiments concerning this subject. Our main interest was focused on the following topics: 1. the regeneration pattern of the respiratory epithelium in the trachea, 2. possibilities of the conservation of trachea-transplants, 3. the behaviour of the receptor area against trachea homografts. We found, that in correspondence with clinical observations, even large circumferencial defected epithelial areas in the mucous layer of the trachea have been regenerated in a form of new mucous membrane which showed no morphological difference from normal structure. Segments of trachea can be preserved in Cialit solution. Prefixation in formaldehydsaline fixative improves the preservation of the tissue structure. Homografts obtained in the above described technique could almost always be made to heal, either directly in the trachea or in the subcutaneous tissue of the recipient-animals. The behaviour of the cartilage and the epithelium is demonstrated by histological methods as well as by scanning electronmicroscopy.

Animals↗
PubMed1977

Effect of urethral stretch on urethral pressure profile.

Urethral pressure profiles were recorded in anesthetized dogs with the urethra in both the relaxed and stretched positions. Similar studies were done with fresh specimens of intact dog bladder and urethra removed en bloc. Clinical studies were performed on women during surgical correction of stress incontinence. The pressure profiles reflected the intrinsic smooth muscular activity of the urethra, inasmuch as they were all obtained under full relaxation by anesthesia and with the abdomen open. In all cases, functional as well as anatomical lengths of the urethra were increased with stretch. The rise in urethral closure pressure was most marked in the proximal third of the urethra. Changes were more notable in women with stress incontinence than in the normal dog. Similar results were noted in the in vitro studies. Length-tension properties of smooth and striated muscles offer a clear explanation for the rationale and effectiveness of surgical procedures done for the correction of stress incontinence.

Animals↗
PubMed1977

[Comparative study of bone mineral densities in the human skeleton].

The different mineral densities and their distribution within human bone of the iliac crest, the femoral and the humeral head are analysed by microradiography with computerized photometry. 10 male and 11 female corpses between the age of 17 to 80, show that the results obtained depended upon age, sex and upon the site of the bone biopsy. Bcause of the small number of cases in this preliminary investigation, careful interpretation of these differences is mandatory. The advantages of this method are discussed.

Adolescent↗
PubMed1976

The effect of vasopressin and triglycyl lysine vasopressin (glypressin) on the splanchnic circulation in cirrhotic patients with portal hypertension.

In four cirrhotic patients with portal hypertension we have measured some hemodynamic parameters over 60-120 min; portal venous pressure, hepatic venous pressure, mean arterial blood pressure, hepatic blood flow, transsinusoidal vascular resistance and splanchnic oxygen uptake under treatment with Vasopressin (1 IU/min for 10 min) and glypressin (50 mug/kg body weight). The effect on the parameters was less pronounced with glypressin but of longer duration.

Abdomen↗
PubMed1976

Secretin-induced insulin response. I. Cubital insulin concentration in normal, obese and pancreatectomized patients, including portal insulin concentration in normals after secretin.

Intravenous injection of the gastro-intestinal hormone secretin elicits an increase in the insulin concentration in the cubital vein. In 10 normal weight non-diabetics and 10 obese non-diabetics the latter group gave a hypernormal insulin response. By the simultaneous determination of the insulin concentration in the cubital and portal veins and also by an investigation of 2 pancreatectomized patients, it was demonstrated that an increase in the cubital insulin concentration following intravenous injection of secretin was due to an altered secretion from the pancreas and not to an altered elimination of insulin.

Adult↗
PubMed1976

Fibrinogen related antigens in acute pancreatitis.

The fibrinogen related antigens were measured in 22 consecutive patients with acute pancreatitis. During the attack a marked elevation was seen, the values normalizing in the quiet phase. This may be due to either intravascular and/or extravascular degradation of fibrinogen-fibrin. As other authors have demonstrated intravascular coagulation experimentally in animals with pancreatitis, the authors stress that intravascular coagulation may play an important role in the patheogenesis of acute pancreatitis.

Acute Disease↗
PubMed1975

[Functional studies on the differential diagnosis of so-called cardiospasm and esophageal achalasia. Simultaneous electromanometric and serial radiographic studies].

The characteristic esophageal pressure tracings and radiological appearances of diffuse spasm and achalasia are reported. In two patients of the series spastic activity involves the gastroesophageal junction. The findings indicate that differentiation of so-called cardiospasm and achalasia can only be obtained by simultaneous electromanometric pressure measurement and serial film technique. The resulting surgical methods are briefly reviewed.

Adult↗