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51.
Alan Shiels Stephen Jeffery Ian R. Phillips Elizabeth A. Shephard Catherine A. Wilson Nicholas D. Carter 《Biochimica et Biophysica Acta (BBA)/General Subjects》1983,760(3)
Using radioimmunoassay, the concentration of carbonic anhydrase III in the livers of adult male rats was found to be approx. 30-times greater than that observed in mature females. Castration of male rats led to a marked reduction in liver carbonic anhydrase III concentrations which could be partially restored to control levels by testosterone replacement. Administration of testosterone to ovariectomised female rats induced about a 5-fold increase in liver carbonic anhydrase III concentration. Immunoprecipitation analysis of the products of liver mRNA translation in vitro with antiserum specific for carbonic anhydrase III showed that hormonal control of the levels of carbonic anhydrase III in liver is mediated by changes in the amount of translatable carbonic anhydrase III mRNA. Marked changes in liver carbonic anhydrase III concentrations were also observed in developing and ageing male rats. 相似文献
52.
A. J. Cochran W. G. S. Spilg Rona M. Mackie Catherine E. Thomas 《BMJ (Clinical research ed.)》1972,4(5832):67-70
Leucocytes from 46 melanoma patients, 45 breast carcinoma patients, and 95 control donors were tested by the leucocyte migration test against the supernatants of homogenates of malignant melanomas, breast carcinomas, simple breast tumours, and breasts showing simple cystic disease. By comparison with controls inhibition of migration occurred significantly more frequently when tumour patients'' leucocytes were exposed to extracts of histogenetically similar tumours.Cell-mediated immunity to tumour-associated antigens was measured in 12 patients with breast carcinoma and 12 with malignant melanoma immediately before surgical operation and in the postoperative period. All patients tested before operation showed significant inhibition of migration on contact with extracts of histogenetically similar tumours. Postoperatively the degree of leucocyte migration inhibition was reduced in all patients with melanoma and breast carcinoma. Significant inhibition of leucocyte migration returned in most patients 6-22 days after operation. 相似文献
53.
Catherine M. Whittle 《Planta》1971,98(2):136-149
Summary The log. 14C activity/distance profile in the stems of Helianthus seedlings consists of two main parts: region 1, the linear advancing front and region 2, which is also linear but with a less steep slope. As the front passes down the stem, the slope of region 1 remains constant but the amplitude of the front becomes attenuated. The attenuation increases with temperature. The apparent velocity of the profile, which can be derived from the position of the front, is also temperature dependent. Small amounts of 14C occur in the stem ahead of the profile; these amounts increase with a rise of temperature. Region 2 behaves differently: its slope decreases steadily with time but it is insensitive to temperature. The behaviour of this region is dependent on the movement of tracer into an immobile fraction as well as on the longitudinal movement of tracer in the translocation stream. 相似文献
54.
55.
With the use of 32P-labeled phosphate and 42K2CO3 the effect of diphenyl on permeability and uptake properties of the cytoplasmic membrane in wild type and diphenyl-tolerant mutant conidia of Fusarium solani f. cucurbitae was studied. No general damage to the membrane with unspecific leakage of cell constituents was demonstrated under conditions in which diphenyl prevents germination of wild type conidia. The fresh conidia do not require exogenous supply of energy for the uptake of phosphate or of potassium. In the wild type the entry of 32P is inhibited but that of 42K strikingly stimulated by diphenyl. Independently of the tolerant mutant gene present, the mutant conidia are significantly less sensitive to the phosphate uptake inhibition and not affected at all by diphenyl with respect to the uptake of potassium. The latter difference from the wild type seems to indicate genetic control of some property of the potassium transport system in this fungus. 相似文献
56.
Experiments on renal cortical brush border membrane vesicles have been undertaken in order to assess the involvement of iron in oxidative stress at physiological temperatures and under conditions of hypothermia. A decrease in temperature stimulated iron-induced lipid peroxidation. The results are discussed in relation to the role of the oxidation state of the iron and iron(II)/iron(III) ratios in the initiation of peroxidative events. 相似文献
57.
Short- and Long-Term Alterations of Gene Expression in Limbic Structures by Repeated Electroconvulsive-Induced Seizures 总被引:4,自引:2,他引:2
Vincent Leviel Catherine Fayada Bernard Guibert Michel Chaminade Georges Machek Jacques Mallet Nicole Faucon Biguet† 《Journal of neurochemistry》1990,54(3):899-904
Rats were submitted to a series of 10 daily electroconvulsive shocks (ECS). A first group of animals was killed 1 day after the last seizure and a second group 30 days later. Tyrosine hydroxylase (TH) activity was measured using an in vitro assay in the nucleus caudatus, anterior cortex, amygdala, substantia nigra, ventral tegmental area, and locus ceruleus. The mRNA corresponding to this enzyme (TH-mRNA) was evaluated using a cDNA probe at the cellular level in the ventral tegmental area, substantia nigra, and locus ceruleus. Met-enkephalin (MET)-immunoreactivity and the mRNA coding for the preproenkephalin (PPE-mRNA) were assayed in striatum and the central nucleus of the amygdala. The day after the last ECS an increase of TH activity was observed in the ventral tegmental area, locus ceruleus, and substantia nigra in parallel with a similar increase in the amygdala and striatum; in the anterior cortex TH activity remained unchanged. TH-mRNA was increased in the locus ceruleus, evidencing the presence in this structure of a genomic activation. The amounts of MET and PPE-mRNA were unaffected in the striatum but increased in the amygdala. Thirty days after the last ECS we observed a decrease of TH activity in the amygdala and of TH-mRNA amount in the ventral tegmental area. In the locus ceruleus TH-mRNA remained higher in treated animals than in controls whereas TH activity returned to control levels. These results demonstrate that a series of ECS induces an initial increase of the activity of mesoamygdaloid catecholaminergic neurons followed by a sustained decrease through alterations of TH gene expression which could mediate the clinical effect of the treatment. 相似文献
58.
Melvyn P. Heyes† Marios Papagapiou Catherine Leonard Sanford P. Markey † Roland N. Auer†† 《Journal of neurochemistry》1990,54(3):1027-1033
Profound insulin-induced hypoglycemia is associated with early-onset neuronal damage that resembles excitotoxic lesions and is attenuated in severity by antagonists of N-methyl-D-aspartate receptors. Hypoglycemia increases L-tryptophan concentrations in brain and could increase the concentration of the L-tryptophan metabolite quinolinic acid (QUIN), an agonist of N-methyl-D-aspartate receptors and an excitotoxin in brain. Therefore, we investigated the effects of 40 min of profound hypoglycemia (isoelectric EEG) and 1-2 h of normoglycemic recovery on the concentrations of QUIN in brain tissue, brain extracellular fluid, and plasma in male Wistar rats. Plasma QUIN increased 6.5-fold by the time of isoelectricity (2 h after insulin administration). Regional brain QUIN concentrations increased two- to threefold during hypoglycemia and increased a further two- to threefold during recovery. However, no change in extracellular fluid QUIN concentrations in hippocampus occurred during hypoglycemia or recovery as measured using in vivo microdialysis. Therefore, the increases in brain tissue QUIN concentrations may reflect elevations of QUIN in the intracellular space or be secondary to the increases in QUIN in the vascular compartment in brain per se. L-Tryptophan concentrations increased more than twofold during recovery only. Serotonin decreased greater than 50% throughout the brain during hypoglycemia, while 5-hydroxyindoleacetic acid concentrations increased more than twofold during hypoglycemia and recovery. In striatum, dopamine was decreased 75% during hypoglycemia but returned to control values during recovery, while striatal 3,4-dihydroxyphenylacetic acid and homovanillic acid were increased more than twofold during both hypoglycemia and recovery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
59.
Franco D. Menozzi Catherine Menozzi-Dejaiffe Francis E. Nano 《FEMS microbiology letters》1989,58(1):59-63
In order to develop reagents to study the immune response of guinea pigs to infection by Chlamydia psittaci guinea pig inclusion conjunctivitis strain (GPIC), we constructed a plasmid clone bank with C. psittaci DNA. One of the recombinant clones isolated produced large amounts of a 57-kilodalton (kDa) protein that was immunoreactive with sera from GPIC infected guinea pigs. While investigating this recombinant protein, we discovered that all the Gram-negative bacteria analyzed so far have immunoreactive proteins of similar size. This protein seems to be a 'common antigen' already described in various Gram-negative bacteria. 相似文献
60.
A new bacterial alcohol dehydrogenase active on degraded lignin and several low molecular weight aromatic compounds 总被引:1,自引:0,他引:1
Jean Pelmont Catherine Tournesac Ahmed Mliki Michel Barrelle Claude Beguin 《FEMS microbiology letters》1989,57(1):109-114
A new intracellular bacterial dehydrogenase has been purified. It was active in the reversible reduction by NADH of conjugated carbonyl groups in partially degraded lignin. It was also active on various aromatic aldehydes such as vanillin, syringaldehyde and cinnamaldehyde, but had no effect on acetovanillone and lignin models carrying a conjugated ketone. It is proposed that this enzyme functions as a broadly specific lignin dehydrogenase at the level of aldehydic groups that are present in the lignin preparations. 相似文献