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391.
392.
V B Gerazieva I G Mikha?lov T D Kanare?tseva 《Biulleten' eksperimental'no? biologii i meditsiny》1975,80(10):93-96
A change in the activity of succinic dehydrogenase, of the NAD- and NADP-diaphorases was studied in the dissociated culture of the cerebellum of neonatal rats under the effect of immune serum of the animals with an experimental allergic pertussis encephalomyelitis. There was revealed an increase in the activity of oligodendrocytes following a 3-hour exposure with the immune serum and a reduction of the activity of the enzymes under study in the same cells after a 12-hour exposure of the cultures with the serum. In difference from oligodendrocytes, the astrocytes displayed a high activity of all the enzymes under study after a 12-hour exposure. 相似文献
393.
394.
T W Teasdale T I S?rensen A J Stunkard 《Human biology; an international record of research》1992,64(1):99-106
In this study we explore the relationships between intelligence test score, educational level, and degree of body fatness. We collected data on intelligence test score, educational level, height, and weight from a sample of 26,274 young Danish men and computed body mass index (weight/height2) as a measure of fatness. Both intelligence test score and educational level had maximum values below the median for body mass index and declined monotonically thereafter. The decline was equal for test score and educational level and above 32 kg/m2 corresponded to almost half a standard deviation. These results are not readily explained by stigmatization of frank obesity, and other mechanisms, possibly genetic, may be responsible. 相似文献
395.
Early detection of myocardial ischaemia is a central problem in cardiological and cardiosurgical intensive care. A new approach is the use of ion-selective electrodes implanted directly on the myocardium, enabling detection of increased potassium activity as an indication of general hypoxia. After a comprehensive study of the electrode parameters, an animal experiment was carried out, in which it was found that respiration-induced hypoxia resulted in an increase in epicardial potassium activity (p < 0.01). Blood gas analysis performed simultaneously revealed reduced arterial pO2, but no acidosis. Haemodynamic data evidenced hypoxic depression of circulatory parameters. Histological examinations of the myocardium beneath the electrodes revealed typical lymphocytic infiltration. Electron microscopy demonstrated crystolysis in the mitochondria as an early sign of hypoxia, thus confirming the sensitivity of these electrodes. This underscores the potential of ion-selective electrodes for the detection of myocardial ischaemia, and they should now be investigated in the clinical setting. 相似文献
396.
397.
V Ia Bykhovski? N I Za?tseva A F Mironov N S Osin E V Pecherskikh V D Rumiantseva G M Sukhin 《Prikladnaia biokhimiia i mikrobiologiia》2001,37(6):660-668
Methods of synthesis of coproporphyrin and uroporphyrin by using bacteria of the genus Arthrobacter are proposed. Metal complexes of coproporphyrin and uroporphyrin with Pt, Pd, and Zn were synthesized. Their structures were identified by spectrophotometry, IR spectrometry, 1H-NMR, mass spectrometry, and HPLC. Data showing the possibility to use coproporphyrin III-metal complexes as luminophores for fluorescence detection of tumors. The current and prospective uses of metal complexes of water-soluble natural porphyrins in advanced immunofluorescence assays are discussed. 相似文献
398.
M Huber M Lindgren P Hammarstr?m L G M?rtensson U Carlsson G R Eaton S S Eaton 《Biophysical chemistry》2001,94(3):245-256
Phase memory relaxation times (T(M) or T(2)) of spin labels in human carbonic anhydrase II (HCA II) are reported. Spin labels (N-(1-oxyl-2,2,5,5-tetramethyl-3-pyrrolidinyl)iodoacetamide, IPSL) were introduced at cysteines, by site-directed mutagenesis at seven different positions in the protein. By two pulse electron paramagnetic resonance (EPR), electron spin echo decays at 45 K are measured and fitted by stretched exponentials, resulting in relaxation parameters T(M) and x. T(M) values of seven positions are between 1.6 micros for the most buried residue (L79C) and 4.7 micros for a residue at the protein surface (W245C). In deuteriated buffer, longer T(M) are found for all but the most buried residues (L79C and W97C), and electron spin echo envelop modulation (ESEEM) of deuterium nuclei is observed. Different deuterium ESEEM patterns for W95C and W16C (surface residue) indicate differences in the local water concentration, or accessibility, of the spin label by deuterium. We propose T(M) as a parameter to determine the spin label location in proteins. Furthermore, these systems are interesting for studying the pertaining relaxation mechanism. 相似文献
399.
400.
Zooplankton in the artificial pond of the Botanical Garden of the Jagiellonian University in Kraków.
Paramecium caudatum and the predominant zooplanton organisms were registered in the studied pond of the Botanical Garden of the Jagiellonian University in Kraków. The finding of Stentor coeruleus indicates an improvement in the environmental conditions in Kraków, connected with the partial liquidation of the huge steelworks. 相似文献