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Biomedical subjects

R Fischer

Publications and source records attributed to R Fischer.

At least 739 records · Page 41Linked to original sources
PubMed1975

Spontaneous variations in the cell population of a T-cell lymphoma during tissue culture and transplantation.

Immunologically induced T-cell lymphomas were kept for long period fo time in isotransplantation and in tissue culture. Initially, a certain number of cells within the tumor showed differentiation towards histiocytes. These disappeared completely after about the twentieth graft generation when the tumor changed toward a more atypical and more uniform neoplasm. That change was correlated with a decrease in transplantability, a limited growth in tissue culture, and a decrease in density of theta antigens on tumor cell membranes. While the original tumor and early grafts contained occasional C-type particles, these were never demonstrated in late tumor grafts. The possible implications of these changes are discussed.

Animals↗
PubMed1975

[Quantitative determination of fragment erythrocytes (schistocytes) in healthy subjects and patients after surgery].

Fragmented erythrocytes (schistocytes) were counted in blood subjects and from 50 patients who underwent various surgical procedures. The results showed to be as follows: 1. The average number of schistocytes in healthy controls of both sexes was 1-20/00 (medium in Thoma chamber 1.4%0/00, in blood smears 2.030/00, with a range from 0-50/00 and 0-60/00, respectively). 2. There was an increase in the number of schistocytes two hours after a surgical procedure (average 60/00), the degree of which correlated with the extent of the operation. Higher values of fragmented erythrocytes were counted after intraoperative blood transfusion (average 100/00). In most cases schistocyte values returned to normal at about 24 hours after surgery. 3. The highest schistocyte counts (18-350/00) were observed in two patients undergoing splenectomy with persistence of elevated counts for a longer period. 4. The average schistocyte number in stored blood of various age was 2.50/00. 5. Both counting of schistocytes in Thoma chambers and in blood smears are applicable, though the values obtained with the latter technique are slightly higher. Quantitative estimtion of schistocytes proves a useful method for evaluating disturbances in microcirculation.

Adult↗
PubMed1975

[The vaso-active intestinal polypeptide in Verner-Morrison syndrome].

A 40-year-old man with the Verner-Morrison syndrome (refractory watery diarrhoea and hypokalaemia in islet-cell tumour of the pancreas) had an islet-cell carcinoma of the non-B-cell type with metastases to liver and mesenteric lymph nodes. High concentrations of a vasoactive intestinal polypeptide (VIP) were demonstrated in tumour tissue and plasma by radioimmunological tests. After surgical removal of the tumour the plasma VIP concentration fell to normal. Immunohistochemical tests of the tumour for gastrointestinal hormones demonstrated marked fluorescence only for vaso-active intestinal polypeptide. It is assumed that this polypeptide is largely responsible for the clinical signs. In the described case the severe watery diarrhoea ceased after glucocorticoid administration.

Acute Kidney Injury↗
PubMed1975

Morphological classification of malignant lymphomas: ultrastructural, cytochemical and immunological results.

Except for tumors clearly producing immunoglobulin (e.g. plasma-cytoma), the different classes of malignant lymphomas do not correlate with a constant surface immunoglobulin pattern. Beside a prevailing IgM-surface type in a high number of different lymphoma classes even T-like or O-cells occur in most tumor types provided they are studied in a sufficient number. The possibility of dedifferentiation of immunologic cell qualities has to be envisaged. In this context intracellular lambda-chain crystals occurring in chronic lymphocytic leukaemia may provide a morphological hallmark of anaplastic deterioration of immunoglobulin synthesis. - The ambiguous significance of PAS-positive inclusions and virus-like microtubular complexes in lymphoma cells is discussed. - In conclusion the recent discovery of hairy cell leukaemia provides a good example of the value of nomenclatures based on empiricism rather than on short-lived theories.

B-Lymphocytes↗
PubMed1975

[Cytochemical polymorphism of acid phosphatase in hairy cell leukemia].

In four cases of hairy cell leukemia a cytochemical polymorphism concerning acid phosphatase (AP) is evident. Any AP is lacking in all hairy cells of one case; only tartrate inhibitable AP is occurring in two cases, in another case tartrate resistant AP is found in high activity. Thus, the lack of tartrate resistant AP seems not to be an argument against hairy cell leukemia.

Acid Phosphatase↗
PubMed1975

Therapeutic usefulness of hallucinogenic drugs as a function of their chemical structure.

D-lysergic acid diethylamide (LSD) displays (1) the phenylethylamine pattern present in mescaline, cyclazocine and catecholamines and (2) the 4-substituted tryptamine structure of psilocybin which is a serotonin analog. Hence (a) Naloxone--a blocker of the LSD-like side effects of cyclazocine--should (and does) block effects of LSD, and (b) cross-tolerance may be present between LSD and cyclazocine but not between mescaline and psilocybin. Even though LSD binds subcortically, its effect on regional perfusion of the brain and, presumably, function is primarily cortical and, since the perfusion shifts evoked by psilocybin are confined to subcortical regions, we assume that other compounds with the phenylethylamine structure such as mescaline, also may selectively affect cortical activity.

Binding Sites↗
PubMed1975

Occurrence of polyamines in coliphages T5, phiX174 and in phage-infected bacteria.

The polyamine spermidine and the diamine putrescine have been detected in coliphages T5 and phiX174. Polyamines were identified by thin-layer chromatography and mass-spectrometry of dansyl derivatives, as well as by ion-exchange chromatography. In phiX174 phages, polyamines were sufficient to neutralize 0.5% of DNA phosphates. The polyamine content of T5 phages depended on growth media and purification procedures, but at least 1% of DNA phosphates were neutralized by polyamines. After infection, an increase in cellular polyamine was noticed. This increase paralleled variations in ornithine decarboxylase activity.

Carboxy-Lyases↗
PubMed1975

Gastrojejunostomy inhibits postshunt siderosis.

Thirteen of fourteen dogs developed marked increases in hepatic hemosiderin (postshunt siderosis) after construction of portacaval shunt, whereas only three of 12 dogs developed such siderosis after construction of a portacaval shunt and end-to-side gastrojejunostomy with duodenal exclusion. Splenic hemosiderin was increased markedly in dogs with portacaval shunt but increased minimally in dogs with portacaval shunt and gastrojejunostomy. Rib marrow fat increased slightly in dogs with portacaval shunt and decreased slightly in dogs with portacaval shunt and gastrojejunostomy. Thus continued iron absorption appears to account for the development of postshunt siderosis and the addition of gastrojejunostomy ameliorates postshunt siderosis by diminishing iron absorption.

Adipose Tissue↗