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Biomedical subjects

R Fischer

Publications and source records attributed to R Fischer.

At least 721 records · Page 40Linked to original sources
PubMed1976

Mechanism of inhibition of cholesterol uptake by the arterial wall.

Experiments have been described dealing with lipid synthesis and cholesterol uptake in perfused human and pig coronary arteries, rabbit aortas, and with the inhibitory effect of 7-ketocholesterol on cholesterol uptake in these preparations and in rabbits in vivo. Human and pig coronary arteries failed to synthesize cholesterol in vitro. 7-ketocholesterol inhibited cholesterol uptake in human coronary arteries and aortas of pigs and rabbits in vitro and by rabbit aortas in vivo. The inhibitory effect in vivo could only be shown after repeated i.v. injections of 7-ketocholesterol after solubilizing the steroid with bile sale (Na-glycocholate). Although 7-ketocholesterol was absorbed from the G.I. tract, gastric feeding of the bile salt steroid complex was ineffective, probably because of inadequate blood levels of 7-ketocholesterol achieved. The metabolic fate of 7-ketocholesterol and the nature of its effect on cholesterol are discussed. It is not likely that inhibition of HMG-CoA reductase is responsible for the inhibition of cholesterol uptake. The possibility was discussed that both cholesterol and 7-ketocholesterol actively compete for identical and specific binding sites or that an increase in 7-ketocholesterol in plasma leads to an increase in intracellular concentrations of this steroid thus inhibiting cholesterol transfer across the cell membrane. However definite conclusions on the nature of inhibition must await further experimentation.

Acetates↗
PubMed1976

In vivo inhibition of cholesterol uptake in rabbit aortas by 7-ketocholesterol.

The iv injection of 7-ketocholesterol into rabbits, made soluble by combining with bile salts, inhibited cholesterol uptake by the aorta. However, the inhibition was not as marked or as uniform as previously demonstrated in in vitro experiments. This difference may have been the result of lower plasma concentrations of 7-ketocholesterol in the injected animals. Gastric feeding of 7-ketocholesterol failed to inhibit aortic cholesterol uptake, probably because of inadequate plasma concentrations of the inhibitory steroid. The results suggest that the mechanism of 7-ketocholesterol on aortic cholesterol uptake is through competitive inhibition.

Animals↗
PubMed1976

Hypnotic recall and flashback: the remembrance of things present.

There are two kinds of flashbacks: the self-programed or intra-individual variety and pre-programed or inter-individual flashbacks re-presenting mythical and narrative event structures which contribute to the survival of the species. Both types of experiences are arousal-state bound and stage (set and setting) or culture bound. Flashbackers may be characterized by (1) their variability (large SD) on perceptual-behavioural tasks pointing to their extensive cognitive or interpretive repertoire, (2) they are minimizers (or reducers) of sensory input (particularly at the peak of a hallucinogenic drug experience), (3) as a group they display high resting heart rates, (4) are hypnotizable and experience), (3) as group they display high resting heart rates, (4) are hypnotizable and hence (5) prefer righ cerebral hemispheric cognition, (6) displaying EEG-alpha dominance in the resting, waking state. Flashback and hypnotic recall differ only in the ways and means by which they are induced. Hypnotic induction, however, is not to be confused with the induced state that may be any ordinary or non-ordinary state of consciousness on the perception-hallucination-meditation continuum which the subject has a least once experienced before. If mind is an open system comprising the individual's mind and the minds of his total environment, i.e. his past and present sets and settings, then for many of us thoughts and actions are hypnotically induced, and memories are flashbacks of those experiences.

Arousal↗
PubMed1976

[Membrane receptors of lymphoreticular cells in hyperplastic and neoplastic diseases of the lymphatic system].

The results of T- and B-cell determinations are described in 105 cases of lymphoreticular and lymphoepithelial neoplasia, and are compared to similar investigations of 582 cases as published in the literature. In addition, T- and B-cell values are determined in blood of 35 healthy individuals, in 12 normal lymph nodes, as well as in hyperplastic conditions of lymph nodes from 30 patients and of tonsils from 85 patients. Cell characterizations are done by immunofluorescence and use of monospecific anti-immunoglobulin antisera (H chain specific), anti-thymus antiserum, as well as by the E-rosette test. While normal blood and normal and hyperplastic tissues show a polyclonal distribution or proliferation of lymphoreticular cells, neoplastic conditions are often characterized by an exuberant, possibly monoclonal proliferation of one cell type. According to this, lymphoreticular neoplasias are immunologically grouped into four main classes: B-cell neoplasias comprising most of the chronic lymphocytic leukemias, well differentiated lymphocytic lymphomas, BURKITT's tumor, follicular lymphoma BRILL-SYMMERS, and hairy cell leukemia. T-cell lymphomas represent a large part of poorly or undifferentiated leukemias of children, poorly differentiated lymphocytic lymphomas, prolymphocytic leukemia, and Sézary's syndrome. Monocytic neoplasias are malignant histiocytoses and leukemic reticuloendothelioses. A fourth group, which probably is not homogeneous and might be further classified in the future by use of more sophisticated methods, consists of tumors with T- and B-cell lack. Such tumors are histologically classified as Hodgkin's lymphomas, a certain number of histiocytic lymphomas, and mycosis fungoides. The prognostic and pathogenetic implications of a combined morphological and immunological classification of lymphoreticular neoplasias are briefly outlined.

B-Lymphocytes↗
PubMed1976

[Classification of malignant lymphomas of the neck: combined morphological, immunocytological, serological and tissues culture studies (author's transl)].

81 untreated malignant lymphomas of the neck were classified morphologically according to the German Kiel classification and to the American classification of Rappaport and Berard and these tumors were typed immunologically as to their T- or B-cell nature. Cells from 16 of these patients were subsequently grown in tissue culture for periods up to seven months. Tissue culture cells were monitored as to spontaneous variations in the morphologic cell type and to the expression of T- or B-cell surface determinants. In addition in 10 patients sera were tested for anti-Epstein-Barr virus (EBV) antibodies. The results of these investigations were correlated with the course of the individual neoplastic disease. Significantly elevated titers against EBV antigens were detected primarily in 8 of 10 patients, mainly in lymphocytic lymphomas respective lymphoplasmacytoid immunocytomas. All such neoplasms belonged immunologically to B-cell lymphomas and were readily grown in tissue culture. The morphological cell type and the expression of B-cell determinants showed some variation during the culture period. In contrast,lymphomas of EBV-negative patients or patients with low EBV-titers grew poorly in tissue culture and remained morphologically more stabile. Immunocytologically they belonged to tumors with B- and T-cell deficiency and were classified primarily as histiocytic lymphomas and as Hodgkin's lymphomas. The clinical course in slow proliferating tumors seemed to be rather disadvantageous.

Antibody Formation↗
PubMed1976

[Clinic and therapy of idiopathic hemochromatosis. Report of 51 cases (author's transl)].

Idiopathic hemochromatosis is a genetical defect leading to continuous accumulation of iron. Symptomatology is caused by iron deposition in different organs. Phlebotomy is by far the most efficient therapy. Case reports are given of 51 cases in different stages of the disease, all of which were proved by biopsy. Taking into account data of these cases some aspects of heredity, history and clinical symptomatology of this metabolic disease are discussed; histological and peritoneoscopic findings during the course of the disease under management by phlebotomy are demonstrated. On 46 patients treated in this was 25 were freed of iron deposits and 5 improved. In most cases there was a reduction of collagenous tissue in the liver. In some, and even in far advanced cases, almost complete anatomical and clinical normalization could be reached. Prognosis depends upon early diagnosis and consequent long-term treatment by phlebotomy.

Adult↗
PubMed1976

[Studies on the immunologic specificity of the macrophage-electrophoresis mobility test in mice with syngeneic and allogeneic transplants of mammary carcinoma].

The study was performed to answer the question as to whether the macrophage electrophoretic mobility test (MEM-test) is suitable to detect allogeneic and syngeneic lymphocyte sensitization in the murine mammary tumour host system. Lymph node cells of both CBAf and XVII/Bln mice injected with allogeneic or syngeneic mammary tumour cells reacted specifically to hypertonic KCl extracts from allogeneic or syngeneic mammary tumours. Lymph node cells of nontreated control mice did not react at all. The MEM results reflect lymphocyte sensitizations which are specific with respect to the claim of transplantation and tumour immunology in the system employed.

Animals↗
PubMed1976

Transformations of consciousness. A cartography, II. The perception-meditation continuum.

The Japanese Zen and Indian Yoga meditation techniques of zazen, dhārnā, dhyān, savichār- and nirvichār-samādhi are cartographed on a perception-meditation continuum of increasing trophotropic arousal. Certain psychophysiological characteristics and experiential dimensions of these hypometabolic states are discussed and it is proposed that observer-observed interactions or trans-substantiation (commonly termed 'reality') may not be subject to Goedelian restrictions if they proceed in hyper- and hypoaroused states. The meaning of aroused, non-verbal and logically non-Aristotelean states cannot be conveyed to individuals in a non-aroused state. The converse is also true when the relationship of arousal levels is reversed.

Arousal↗