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81.
Human erythrocyte and brain acetylcholinesterase are preferentially inhibited by the P(-)-isomers of C(+/-)P(+/-)-soman. The enzymes inhibited by the P(-)-isomers behave similarly with respect to oxime-induced reactivation and aging. HI-6 is the best reactivator for C(+)P(-)-soman-inhibited acetylcholinesterases. Oxime-induced reactivation of the C(-)P(-)-soman-inhibited acetylcholinesterases is much more difficult to achieve. 相似文献
82.
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84.
M Garnier G de Preville P Pilardeau D Boudia 《Comparative biochemistry and physiology. A, Comparative physiology》1984,77(2):315-317
Internal sodium and lipoprotein composition of RBCs of nine mammalian species are measured. A significant correlation can be demonstrated between the erythrocyte mean sodium value of studied species and the membrane protein/lipid ratio (r = 0.80, alpha less than 0.01). Erythrocyte internal sodium can be correlated with membrane-free cholesterol but not with the phospholipid fractions. 相似文献
85.
The concentration of immunoreactive arginine-vasopressin (IR-AVP) was measured in the cerebrospinal fluid (CSF) during acquisition and retention of passive avoidance behavior. IR-AVP level in CSF of male Wistar rats immediately after the learning trial was increased; the rate of which was related to the intensity of the electric footshock during the learning trial and the avoidance latency as measured 1 day after the learning trial. Immediately after the 24 h retention test IR-AVP levels were significantly increased in rats subjected to the low (0.25 mA) shock intensity during the learning trial, but IR-AVP levels of rats exposed to the high shock (1.0 mA) were under the limit of detection. If the retention test was postponed till 5 days after the learning trial, the increase of IR-AVP level in the CSF was related to avoidance latencies which reflect the intensity of aversive stimulation (electric footshock). The results suggest an association between central AVP release and passive avoidance behavior and may be indicative of the role of this peptide in neuronal mechanisms underlying learning and memory processes. 相似文献
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87.
A search for differences due to ANS staining (hydrophobia), Con A and PNA binding capacity, and birefringence was carried out on stratified epithelia of rat skin and human breast cells (HBC) in culture. Microfluorimetric measurements confirm that the ANS fluorescence of the stratum corneum from adults is higher than that of newborns. HBC exhibited an unexpected deep ANS-fluorescence. Differences in the binding capacity of the epithelial layers to Con A and PNA were detected with advancing age. Retardation measurements revealed that the form birefringence of the stratum corneum is higher in adult animals specially as revealed by the fact that its form birefringence curve branch from n = 1.414 to n = 1.479 is steeper, i.e. depict higher values. The strong birefringence of the cytoplasmic tonofilaments presented by cultured human breast cells was considered an unexpected finding and attributed to changes that the cells underwent following the in vitro conditions. 相似文献
88.
G Decat A Léonard W de Meurichy 《Comptes rendus des séances de la Société de biologie et de ses filiales》1982,176(3):373-377
The harlequin-staining technique has been used to study the cell kinetics and the radiosensitivity of PHA-stimulated lymphocytes from Cercopithecus nictitans. C. aethiops var. cynosorus, C. irus, and C. ascanius. At 48 hours, the fixation time normally used for human lymphocytes, a large heterogeneity appears between the four species, with respect to the incidence of cells in first, second or third mitoses. If analysis of lymphocytes is restricted to Ml dividing cells, the yield of radiation-induced chromosome aberrations does not differ significantly from the incidence observed in irradiated human lymphocytes. 相似文献
89.
da Paz Priscila Marques de Oliveira Juliana 《Bioprocess and biosystems engineering》2018,41(5):697-706
Bioprocess and Biosystems Engineering - This work is based on the importance of monitoring the thermodynamic variables of sugarcane juice fermentation by Saccharomyces cerevisiae, using a numerical... 相似文献
90.
We describe a bioluminescent immunoassay procedure which does not require a separation step to remove excess free label. A luminescent immunosorbent constituted of bacterial luciferase, FMN oxidoreductase, and an antibody coimmobilized on Sepharose is used to determine specifically the label enzyme (glucose-6-phosphate dehydrogenase, coupled to an antigen) bound by a specific antibody. The immunosorbent confines the bioluminescent reaction in a small volume, and the bound label produces NADH, which is directly used by the nearby luciferase FMN oxidoreductase enzyme system. On the contrary NADH produced by dehydrogenases in solution is directly oxidized without emitting light. Dehydrogenases contained in the biological sample do not interfere with the assay, which can be performed directly on 25 microliter of serum. In this paper we describe the general procedure and we analyze the different parameters that must be optimized. 相似文献