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41.
Wójcik C 《Cellular and molecular life sciences : CMLS》1999,56(11-12):908-917
The proteasome (multicatalytic proteinase complex, prosome) is a major cytoplasmic proteolytic enzyme, responsible for degradation of the vast majority of intracellular proteins. Proteins degraded by the proteasome are usually tagged with multiple ubiquitin moieties, conjugated to the substrates by a complicated cascade of enzymes. Over the last years, evidence has accumulated that changes in the expression and activity of the different components of the ubiquitin-proteasome system occur during apoptosis. Proteasome inhibitors have been used to induce apoptosis in various cell types, whereas in others, these compounds were able to prevent apoptosis induced by different stimuli. The proteasome mediated step(s) in apoptosis is located upstream of mitochondrial changes and caspase activation, and can involve in different systems Bcl-2, Jun N-terminal kinase, heat shock proteins, Myc, p53, polyamines and other factors. 相似文献
42.
F. J. Oliver M. K. L. Collins A. López-Rivas 《Cellular and molecular life sciences : CMLS》1996,52(10-11):995-1000
Fidelity in DNA synthesis and repair is largely dependent on a balanced supply of deoxynucleotide triphosphate (dNTP) pools. Results from different groups have shown that alterations in dNTP supply result in DNA fragmentation and cell death with characteristics of apoptosis. We have recently shown that in apoptosis driven by deprivation of interleukin-3 (IL-3) in a murine hemopoietic cell line, there is a rapid imbalance in the availability of dNTP that precedes DNA fragmentation. In these cells, dNTP pool balance is closely coupled to the function of the salvage pathway of dNTP synthesis. Apoptosis, induced by treatment of these cells with drugs that inhibit the de novo dNTP synthesis, is prevented when dNTP precursors are supplied through the salvage pathway. IL-3 regulates thymidine kinase activity, suggesting that alterations in dNTP metabolism after IL-3 deprivation could be a relevant event in the commitment of hemopoietic cells to apoptosis. 相似文献
43.
Properties of granules that contain kallikrein and renin 总被引:1,自引:0,他引:1
44.
S. Tóth L. Muszbek T. Szilágyi J. Laczkó 《Cellular and molecular life sciences : CMLS》1969,25(10):1085-1086
Zusammenfassung Kasein, Pepton bzw. Baktokasiton wurde als präparierende Erstinjektion für lokalisiertes Shwartzman-Phänomen an Kaninchen verwendet. Nach provozierender i.v. Endotoxininjektion kommt es zum typischen Shwartzman-Phänomen. Da die verwendeten Substanzen Chemotaxis von Leukozyten verursachen, ist anzunehmen, dass die an Stelle der präparierenden Injektion angesammelten Leukozyten in der Ausbildung des Shwartzman-Phänomens eine vorwiegende Rolle spielen. 相似文献
45.
A Dautigny I Bernier J Jollès J Colombani P Jollès 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(16):1535-1536
Two serologically active urinary glycoproteins (HLA-A 9 and HLA-B 12) were isolated from urine provided by a patient suffering from tubular proteinuria. Their N-terminal sequences were automatically determined. The latter were identical with the sequence of another urinary glycoprotein (protein HC). The relationship between protein HC and the serological activity is discussed. 相似文献
46.
Summary The effect of orotic acid on the liver glycogen content in the mice, frogs and catfish was studied. It was observed that the orotic acid significantly increases the glycogen content in the liver of mice and catfish as it does in rats. On the other hand it causes a fall of the glycogen level in frogs in experiments made both in autumn and spring. This effect was modified by amino acids administrated together with orotic acid. 相似文献
47.
K. Wŀodarski S. Mazur M. Jakóbisiak 《Cellular and molecular life sciences : CMLS》1982,38(9):1105-1106
Summary The absolute number of mast cells in regional lymph nodes decreases on the 5th day after stimulation by allogeneic lymphocytes and semisyngeneic leukaemic cells, despite the enlargement of stimulated lymph nodes. It is postulated that the reaction of lymphatic mast cells could be a sensitive test for tissue incompatibility, and probably also for the presence of tumor associated antigens. 相似文献
48.
S. Barrigón J. Tamargo P. D. Garcia de Jalón 《Cellular and molecular life sciences : CMLS》1978,34(6):770-770
Summary Bunaphtide induces a blockade in the3H-norepinephrine uptake and retention in the isolated guinea-pig left atrium. However, this blockade does not seems to be related with the cardiodepressant effect of the drug. 相似文献
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