Search PubMed⌕ Search

Biomedical subjects

M Friedrich

Publications and source records attributed to M Friedrich.

At least 235 records · Page 13Linked to original sources
PubMed1988

Absence of effect of heparin on insulin secretion.

Bioartificial pancreatic devices containing isolated islets of Langerhans have been designed, in which the blood of the recipient circulates in contact with an artificial membrane, protecting the islets against immune rejection. This system assumes that heparin, required to prevent blood clotting, does not alter insulin secretion. However, heparin has been reported to inhibit in vitro insulin secretion by rat islets and to suppress in vivo insulin secretion in dogs. Therefore, the following evaluation was made on the effect of different heparin preparations on insulin secretion. (a) Isolated rat islets of Langerhans were perfused or incubated in the absence or presence of 20 micrograms/ml heparin; insulin secretion in response to a stimulation by glucose 20 mM was not altered by the presence of heparin. (b) Insulin secretion by an insulin-secreting cell line (RINm5F) in response to leucine and theophylline was not suppressed by heparin up to 100 micrograms/ml concentration. However, an inhibitory effect was observed at 200 micrograms/ml, which is 100 times higher than the heparin concentration commonly used for therapeutic use. (c) Neither in normal rats nor in dogs did heparin alter portal plasma insulin levels and the increase in plasma insulin following an intravenous injection of glucose. In conclusion, these data do not confirm the formerly observed inhibitory effect of heparin, which can therefore be used for the in vivo evaluation of a bioartificial pancreas.

Animals↗
PubMed1987

Improvements of metabolic imbalances after enteral sodium bicarbonate supplementation in infants of very low birth weight (VLBW).

One of the main points of clinical care is the catch-up growth of VLBW infants especially those of small gestational age (SGA). The required high amounts of protein are often not tolerated [1]. Metabolic imbalances due to immaturities of protein metabolism are described [2, 3] also in infants SGA feeding amounts of proteins comparable to mature newborns [4]. Remarkable signs of overloading by proteins are the elevation of amino acid and the bile acid concentrations in the serum [3, 5, 6]. In some of those cases [7] late metabolic acidosis (LMA) is to be seen. There is evidence in the literature that sodium bicarbonate influences nitrogen [8] and ionic balances [9] in newborn animals without any signs of acidosis, besides its simple buffer function. The aim of this study was to control changes of metabolic imbalances after bicarbonate supplementation before development of acidosis in predisposed infants. Therefore we determined parameters, which were significantly changed with LMA [6] during two feeding schedules: firstly, during bolus supplementation in infants feeding (2.0 +/- 0.4) g/kg BW.d protein and secondly during chronic supplementation of bicarbonate to (3.0 +/- 0.4) g/kg BW.d protein. In relation to the improvement of the nitrogen balance in growing lambs [7] we supposed comparable effect of bicarbonate on metabolic imbalances caused by protein overloading.

Bicarbonates↗
PubMed1987

[A simple attachment for superficial sonography].

Electronic linear array transducers usually have a discrepant electronic (in scanning plain) and mechanical (perpendicular to scanning plain) focal zone. The "effective" focal zone can only be determined with a true cyst phantom. With transducers of medium frequency the focal zone is about 3-6 cm from the transducer surface, rendering a water path necessary for sonography of superficial organs. The considerable thickness of layer in the scanning plain of most linear array transducers affects the visualisation of superficial vessels in longitudinal direction. A simple water path attachment for small parts sonography is presented, which enables an automatic "self-indication" of palpable lesions especially in breast sonography.

Humans↗
PubMed1987

[Clinical experiences with ultrasound-reflection computerized tomography of the breast].

Ultrasound-reflection computed tomography (URCT) of the breast can produce astonishingly detailed high resolution images of the breast, particularly in the coronal plane. In some cases it improves the demonstration of the structure of scirrhous carcinomas in this plane. On the other hand, some valuable diagnostic features known from conventional breast sonography, such as acoustic shadows and hyper-reflective area (cysts) are suppressed on URCT images and are not readily recognized. Despite individual outstanding images, a comparison carried out on 100 patients showed no advantages of URCT compared with high-resolution real-time sonography.

Adenocarcinoma, Scirrhous↗
PubMed1987

[MR tomography of the breast. Supplemental information in select cases].

Magnetic resonance tomography (MRT), as the newest imaging procedure in breast diagnosis, has to be compared with the combined use of conventional imaging methods. Many advantages of MRT, which have been emphasized in comparison with mammography, are not superior to the complementary use of mammography and sonography. Additional diagnostic information through MRT is yielded only in the following cases: differentiation between fibrous fibroadenoma of the elderly woman and circumscribed carcinoma with similar mammographic and sonographic appearances; distinction of stellated fibrous scar tissue from the scirrhotic configuration of the more vascular tumour fibrosis around a carcinoma by using contrast medium MRT; differentiation of periductal fibrosis from inflammatory or carcinomatous ductal and periductal infiltration; better delineation of fat or silicon implants. Finally, a significant advantage of mammography over all other imaging methods should be pointed out: the detailed visualization of microcalcifications for the early diagnosis of breast carcinoma.

Breast Diseases↗
PubMed1987

Excretion of 15N and incorporation into plasma proteins after high-dosage pulse labelling with various tracer substances in infants.

The suitability of a biosynthetically produced [15N] yeast-protein-thermitasehydrolysate ([15N] YPTH), [15N] yeast protein and [15N] glycine for use as 15N-tracers was tested in three groups of four infants each. The [15N] YPTH was obtained by hydrolysing 15N-labelled yeast protein with thermitase, a proteinase from Thermoactinomyces vulgaris. Following oral single-pulse labelling in a dosage of 10 mg 15N/kg body weight the 15N-excretion in stools and urine as well as the 15N-abundance in plasma proteins and in the TCA-soluble plasma fraction were determined. The [15N] YPTH differs from [15N] glycine in terms of the complete distribution of 15N among all 20 amino acids. This could be demonstrated by a distinctly lower [15N]ammonia (0.5 per cent) and a higher [15N2] urea excretion (5.0 per cent) compared with [15N] glycine (1.2 and 3.4 per cent respectively). The faecal loss of 15N from the [15N] YPTH was 3.7 per cent of the tracer dose, while the corresponding value after administration of [15N] yeast protein was found to be 7.4 per cent on average. There were no differences between the tracer substances in terms of the measured 15N-abundance in the plasma proteins (mean: 0.07 atom per cent excess) and in the TCA-soluble fraction (mean: 0.21 atom per cent excess).

Blood Proteins↗
PubMed1987

[Leiomyosarcoma of the inferior vena cava. Diagnosis--therapy--prognosis].

Leiomyosarcoma of the vena cava inferior is a mesenchymal tumor originating from the smooth muscle fibers of the vascular wall. This tumor is usually slow-growing and expansile growth. Prior to the sonographic and computer-tomographic era the tumor was usually only discovered during autopsy or surgery without any preoperative suspicion. Today, the most efficient imaging methods for exact localization, delineation or demonstration of relations to the vascular lumen and local extent are sonography and computer tomography. Caudal cavography is called upon for preoperative demonstration of the venous collateral circulation and thrombotic vascular occlusion.

Biopsy, Needle↗
PubMed1987

[Protein metabolism and lipid balance in dietary treatment of acute enteritis in infants with a defined standardized oligopeptide diet].

The advantage of a standardized oligopeptide formula (Peptisorb päd) for dietary management of diarrhea was proved in 10 infants aged 1 to 10 months with body weights between 4000 and 8860 g. The nitrogen balance turned to normal already at day 3 to 4 of the treatment due to the rapid increase of food supply. Whole body protein parameters estimated by 15N yeast protein thermitase hydrolyzate as a tracer substance were already normalized at that time. Protein synthesis amounted to 5.0 +/- 1.5 g/kg/day, protein breakdown to 3.7 +/- 1.5 g/kg/day and net protein gain to 1.3 +/- 0.6 g/kg/day, resp. Reutilisation rate of endogenous nitrogen was found to be 83%. This correlates with the relatively high nitrogen supply of the oligopeptide diet in comparison to mother's milk feeding. Approximately 15% of the administered amount of total nitrogen were excreted in the feces in contrast to only 5.8% of the 15N tracer dose, indicating the higher losses of endogenous nitrogen due to enteritis. The absorption of the medium chain triglycerides from the diet was 97.5% at an average and thus extremely high.

Acute Disease↗
PubMed1986

Ultrasound imaging in Peyronie disease.

Fifty-three patients with Peyronie disease were examined sonographically. The use of a water path facilitates good localization and measurement of the fibrotic plaques in the area of the tunica albuginea. Calcifications can be clearly detected. Penile sonography is painless, free of risk, and easy to perform and yields precise morphologic pictures. It is ideal for documentation and assessment of the anatomic alterations in Peyronie disease as well as for control of its course.

Adult↗
PubMed1986

[Magnetic resonance tomography of focal liver lesions in comparison with computed tomography and sonography].

The results of magnetic resonance tomography (MRT) performed in 37 patients with predominantly solitary intrahepatic space-occupying masses are presented. Examinations were carried out with a superconducting magnet operating at a field strength of 0.35 Tesla. The majority of intrahepatic masses exhibited a well distinguishable signal amplification compared to normal hepatic parenchyma when T2 weighted sequences were used. For a further differentiation of the lesion, however, T1 and T2 weighted sequences have to be performed. In all cases diagnostic value of MRT is compared to that of sonography and computed tomography. The assessment of magnetic resonance tomograms of focal hepatic lesions is based on the sequence-depending on the signal behaviour of the mass - especially with regard to morphological criteria. The high soft-tissue contrast of magnetic resonance tomography compensates for the low spatial resolution, thus resulting in a sensitivity of focal lesions comparable to that of sonography and computed tomography. The good visualisation of vessels is an advantage. With the exception of haemangioma, however, MRT does not seem to improve diagnosis of the type of focal hepatic lesions.

Adenoma, Bile Duct↗
PubMed1986

[Ultra-high-strip-density grids for mammography: an alternative to grid mammography?].

New stationary ultra high resolution grids have been proposed as an alternative to the conventional moving grid techniques for mammography. The physical performance of the new grids resembles those of conventional grids with 1:5 grid ratio. They fail during mammography because of their inability to render fine detail and, in particular, the important shapes of micro-calcification.

Breast Neoplasms↗
PubMed1986

[Angiographic and computed tomographic findings in intra-arterial cytostasis of colorectal liver metastases].

Between October 1983 and January 1986, sixteen patients with inoperable liver metastases from colorectal carcinomas were treated by single or cyclical intraarterial chemotherapy introduced either through an angiographic catheter or by means of a subcutaneously implanted access point (Port-A-Cath). Before each treatment cycle, the position of the catheter and the state of the vessels was examined by subtraction angiography in order to avoid complications and to confirm that the cytostatic agents were actually perfusing metastases, as shown by angio-CT. The complementary nature of the information obtained by these methods and their superiority over scintigraphy with 99mTc macroaggregated albumin particles is documented and the most frequent complications of regional tumour therapy are described.

Angiography↗
PubMed1986

[Effect of different types of nutrition on various biochemical indicators in the blood of calves during the first 4 months of life. I. Mineral components and hematological indicators of the blood].

The experiment was conducted on 3 groups of calves. Each group composed of 6 calves from 2-16 weeks of age. In the first group the calves were fed whole milk--milk replacer "Mlekomiks", in the second--whole milk and in the third group--milk replacer "Mlekomiks". Throughout the experiment ale calves were fed good meadow hay and concentrate ad libitum. Analysis of the obtained results showed significant (P less than or equal to 0.01) influence of used feeding method on level of sodium, chloride ions, calcium, phosphorus inorganic and indices of blood hematocrit, ferrum, glucose and amylase as well. There was not observed the relationship in the case of hemoglobin and potassium.

Age Factors↗
PubMed1986

[Effect of different types of nutrition on various biochemical indicators in the blood of calves during the first 4 months of life. II. Blood serum levels of total proteins, its fractions and urea].

The experiment was conducted on 3 groups of calves. Each group composed of 6 calves from 2-16 weeks of age. In the first group the calves were fed whole milk--milk replacer Mlekomiks, in the second--whole milk and the third group--milk replacer Mlekomiks. Throughout the experiment all calves were fed good meadow hay and concentrate ad libitum. Level of total protein was similar in all examined groups of calves but particular protein fractions showed highly significant differences (P less than than or equal to 0.01) due to used diet. Such differences were obtained in level of urea as well.

Animal Nutritional Physiological Phenomena↗