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J Neumann

Publications and source records attributed to J Neumann.

At least 253 records · Page 14Linked to original sources
PubMed1981

[Compartment analysis of potassium metabolism--mathematical modelling of 42-K tracer kinetics].

The possibility of application of the theoretical concept of the compartment analysis in the modelling of the potassium balance was demonstrated. A use of the compartment analysis of the potassium balance in the clinical routine diagnostics in the sense of a highly specialised functional diagnostics seems according to recent experiences reasonable only in closest cooperation with clinicians. The diagnostics and the control of therapy of the chronic syndrome of potassium deficit as well as metabolically conditioned disturbances of the distribution of potassium were to be seen as possible indication. At the same time the establishment of reference values for the demarcation of relative disturbances of distribution as well as for the establishment of the normal region of the turnover rates were necessary.

Body Fluid Compartments↗
PubMed1981

[Compartment analysis in the diagnosis of iron metabolism disorders].

The principle of the ferrokinetics according to the catenary model and to the multilocular system of Pollycove and Mortimer is described in short. The most important results of the investigation of the iron metabolism of 15 patients with chronic myelosis, 31 with osteomyelofibrosis and 68 with chronic liver diseases according to the catenary model are reported. According to the multicompartment model the ferrokinetic investigations of 18 patients with chronic liver disease as well as of one patient each with chronic myelosis and panmyelopathy were evaluated. An increased depot iron metabolism and a decreased effective erythropoiesis could particularly clearly stated in the latter patient. The statements to various parameters according to the two model demonstrations are compared.

Adult↗
PubMed1980

Giant cell gliomas of the temporal lobe.

Giant cell tumours of the brain are commonly a) monstrocellular sarcomas, b) giant cell glioblastomas or gliosarcomas, or c) "giant cell gliomas", i.e. gliomas characterized by many atypical, giant-sized cells with monstrous nuclei. This last group is commonly found in the temporal region and should not be mistaken for a) and b), because, in spite of their "malignant" appearance, these tumours can present benign biological behaviour. Three such cases are described. In two cases the patients received postoperatively neither radio- nor chemotherapy: seven and three years respectively after operation no signs of recurrences were present. A third patient died within two years after operation. However, his tumour had histological signs of malignancy. The importance of exact histological diagnosis is stressed. This prevents misinterpretations in estimating the efficacy of postoperative therapy.

Adult↗
PubMed1980

[On the systematic classification of oligodendrogliomas of grades I to III in tissue cultures (author's transl)].

We report on the in vitro behaviour of 71 oligodendrogliomas. This is the continuation of a systematic investigation on the morphology and biological behaviour of oligodendrogliomas, in line with the investigations of Kersting on the tissue culture of astrocytomas and their recurrences (1973). As reported elsewhere (Neumann et al.) we are able to show an extensive agreement between a histologically based system of grading and the biological behaviour (or follow-up pattern) of the oligodendrogliomas. It therefore seemed worthwhile to reconsider the tissue culture of these tumours, in order to see to what extent the histological classification shows simularities with the behaviour in vitro. One must particularly keep a careful eye on those cultures which come from a tumour which histologically was classified as Grade III, but whose follow-up corresponds much more to the pattern of more benign forms.

Brain Neoplasms↗
PubMed1979

[The slope clearance method in renal functional diagnosis. J-131-hippurate clearance is used as an example].

The clinical relevance of the clearance of radiopharmaca is controversial in literature. The cause for this are in our opinion the different methods of evaluation which either make difficult or make impossible a comparison of individual results. The late phase of the disappearance (at least 70 and 100 min p.i.) possesses a high value under the aspect of renal diagnosis, since by its means with a high approximation the renal function may be established itself.

Hippurates↗
PubMed1979

The serum-free growth of Balb/c 3T3 cells in medium supplemented with bovine colostrum.

Bovine milk contains growth promoting factors that stimulate DNA synthesis and cell division in confluent monolayers of quiescent Balb/c 3T3 cells. The growth factor activity was highest in colostrum obtained within 24 hours after birth of a calf. Samples of milk obtained 32 hours and 60 hours after birth were 20% and 1% as active respectively as was a sample obtained 8 hours after birth in stimulating DNA synthesis. No activity was detectable 3 days after birth or thereafter. A similar temporal dependence was found in sheep's milk. Bovine colostrum obtained on the day of a calf's birth can be substituted for serum and will support the growth of sparse Balb/c 3T3 cells to confluence. In Dulbecco's modified Eagles's medium (DMEM) supplemented with 2.5% (vol/vol) bovine colostrum, the number of Balb/c 3T3 cells in a dish increased 35-fold, from 2.0 X 10(4) cells to 7 X 10(5) cells. The generation time was approximately 38 hours. Proliferation of cells was characterized by formation of clusters of confluent Balb/c 3T3 cells which were smaller in size and more tightly packed than were Balb/c 3T3 cells grown to confluence in serum. No proliferation was detected in DMEM supplemented with milk obtained 10 days after birth of a calf or in DMEM supplemented with bovine serum albumen.

Animals↗
PubMed1979

The identification and clinical implications of human breast milk mitogen.

There are constituents of human breast milk that make it superior to cow's milk for the nutrition, health and development of human infants. We have discovered a new activity in breast milk. We have found in human breast milk a nitrogen that stimulates DNA synthesis and induces division in cells grown in culture. This mitogenic activity is concentration dependent, and also depends on time since lactation. No similar mitogenic activity is found in commercially available formulas or cows milk 1 wk after birthing. The human milk mitogen might be involved in the growth and development of cells in the neonate. It may be important in preventing necrotizing entercolitis and peptic ulceration of the newborn. It might also be used in the treatment of infants following massive small bowel resection.

Breast Feeding↗
PubMed1979

[Biochemical mechanisms for the effect of alcohol on the brain].

This paper reviews and discusses basic knowledge of biochemical mechanisms of action of ethanol upon the central nervous system, the emphasis being on effects upon cerebral membrane structures and processes as well as mechanisms of chemical synaptic transmission. Results of detailed studies into material and steric changes in membranes, ion-dependent adenosine triphosphatases, variations in ion balance, effects upon cyclic nucleotides, influences on special transmitter systems, and mechanisms of formation of morphine-analogous condensation products are presented. In addition, open questions are derived and formulated in problem complexes.

Acetaldehyde↗
PubMed1979

[Evaluation of research findings of potassium metabolism through biological modeling].

The cybernetic modelling of the water balance and the electrolyte balance has a heuristic value for the physiology and pathophysiology, by clearing up connections and open problems. This concerns problems of regulation size and regulation extension, but also the validity of reference values. Under this aspect is referred to the significance of steady state, input- and output inbalances and of the static and dynamic characteristics in the examination of the functional performance of the regulation circle. The static and dynamic compartment modelling is discussed at the instance of the potassium balance and exemplarily confirmed by findings of examinations. Here is referred to the special information value of the dynamic compartment analyse, as apart from the pool sizes (capacities) also intracorporal turnover rates (effects) are established.

Humans↗