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41.
Youssef Dalia El-Bakatoushi Ranya Elframawy Asmaa El-Sadek Laila Badan Ghada El 《Journal of plant research》2023,136(3):305-322
Journal of Plant Research - The current study examined the phylogenetic pattern of medicinal species of the family Apiaceae based on flavonoid groups production, as well as the overall mechanism of... 相似文献
42.
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Ahmed Chadli Jean-Pierre LeCaer Dominique Bladier Raymonde Joubert-Caron Michel Caron 《Journal of neurochemistry》1997,68(4):1640-1647
Abstract: Our previous studies have characterized an endogenous lectin from human brain identified as galectin-1. A soluble ligand of galectin-1 was purified from human brain by affinity chromatography and preparative electrophoresis. The purified ligand (termed HBGp82, for human brain galectin-1-binding polypeptide of 82,000 daltons) has an apparent molecular mass of 82 kDa and is glycosylated by N -linked biantennary complex structures. HBGp82 was partially characterized by microsequencing of peptide fragments. Similar peptides were found in a heat shock of protein of 90,000 daltons, hsp90. However, comparison of apparent molecular weights and matrix-assisted laser desorption mass spectrometry clearly showed that HBGp82 differs to some degree from hsp90. 相似文献
44.
Microwaves induce an increase in the frequency of complement receptor-bearing lymphoid spleen cells in mice. 总被引:2,自引:0,他引:2
W Wiktor-Jedrzejczak A Ahmed K W Sell P Czerski W M Leach 《Journal of immunology (Baltimore, Md. : 1950)》1977,118(4):1499-1502
A single 30-min exposure of mice to 2450 MHz microwaves (12 to 15 mW/g body weight) in an environmentally controlled waveguide facility induced a significant increase in the proportion of complement-receptor positive lymphoid cells in the spleen. This effect was further enhanced by repeated (three times) exposures, which in addition produced a significant increase in the proportion of Ig+ cells. The proportion of theta-positive cells and the total number of spleen cells remained unchanged. 相似文献
45.
Ferdinand Bohlmann Maniruddin Ahmed Harold Robinson Robert M. King 《Phytochemistry》1982,21(7):1675-1678
The investigation of the aerial parts of a variety of Enhydra fluctuans afforded in addition to 4-hydroxyfarnesyl acetate and fluctuadin five new melampolides elucidated by high field 1H NMR spectroscopy. The chemotaxonomic situation is discussed briefly. 相似文献
46.
Summary The effect of growth at 30°, 35° and 40° on the biomass yield and on the nucleic acid and protein content of twelve isolates of yeast has been studied. Although yields of 41.6% and a true protein content of 34% were obtained, each of the strains exhibited a lower yield and protein content at 40° than at the lower temperatures. Nucleic acid levels were also reduced at 40°. 相似文献
47.
Stoichiometry and apparent dissociation constant of the calcium-arsenazo III reaction under physiological conditions. 总被引:1,自引:0,他引:1 下载免费PDF全文
In vitro and in situ tests have been run to characterize the reaction of the mettalochromic indicator, arsenazo III, with calcium. Job plots as well as plots of indicator absorbance vs. [Ca2+] at different indicator concentrations show a 1:1 reaction stoichiometry. Equilibrium analysis and analysis using Adair's equation are also consistent with 1:1 complexes being formed and give estimates of 34 and 45 muM for the apparent dissociation constant. In situ tests were carried out using giant neurons from Archidoris monteryensis, a marine gastropod mollusc. Dye absorbance changes were measured during voltage clamp pulses which produced a fixed calcium influx. The dependence of absorbance change on total dye concentration is consistent with the formation of a 1:1 complex of Ca with ArIII if measurements are made during the initial period of the loading pulse, less than 300 ms, although the apparent dependency changes with longer delay in measurements from the onset of the pulse. 相似文献
48.
T Ahmed A Januszkiewicz P Eyre M J Robinson M A Sackner 《Journal of applied physiology (Bethesda, Md. : 1985)》1981,51(5):1204-1213
We investigated the acute pulmonary hemodynamic effects of intravenous copper sulfate (CuSO4) infusion and its mechanism of action in six groups of conscious sheep (total 40). After 300 mg CuSO4 alone, mean pulmonary artery pressure (Ppa) increased from 10.3 to 22.5 Torr and pulmonary artery wedge pressure (Ppaw) from 3.5 to 7.6 Torr, whereas systemic arterial pressure (Psa) increased from 95 to 102 Torr. Cardiac output (Qp) decreased from 4.7 to 3.3 l/min. Pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) increased to 320 and 160% of base line, respectively. The hemodynamic changes correlated well with serum copper, which increased from a base-line value of 0.12 to 3.5 mg/dl after the CuSO4. Serum dopamine beta-hydroxylase increased from 3.2 U/l before CuSO4 injection to 5.7 after its administration, signifying activation of adrenergic nervous system. H1-histamine receptor blockade with chlorpheniramine failed to prevent the effects of CuSO4. Pretreatment with methysergide, a serotonin antagonist, partially attenuated the effects of CuSO4. Phenoxybenzamine, an alpha-adrenergic receptor blocker, and 6-hydroxydopamine, a catecholamine depleting agent, completely blocked the effects of CuSO4. beta-Adrenergic receptor blockade with propranolol enhanced the effects of CuSO4. We conclude, that, in conscious sheep, acute infusion of CuSO4 caused a marked reversible increase in PVR with a slight transient increase in SVR, and this pulmonary hypertension was produced by stimulation of the alpha-adrenergic nervous system. 相似文献
49.
Summary The degenerative reaction of mitochondria to tricresylphosphate (TCP) poisoning in spinal ganglion cells of Slow Loris (Nycticebus coucang coucang) were studied with the electron microscope. In neurones of animals treated with TCP, mitochondria display various stages of alterations which confirm mitochondrial involvement in TCP poisoning. The role of degenerated mitochondria in the formation of neuronal lipofuscin is discussed. It is suggested that the lipofuscin granule is a metabolic product inherently related to mitochondrial degeneration, irrespective of the primary cause: ageing or intoxication.Fellow of the Deutscher Akademischer Austauschdienst on study leave from the Medical Faculty, University of SingaporeA grant from the Deutsche Forschungsgemeinschaft (Gl. 28/20) is gratefully acknowledgedThe skilfull technical assistance of Mr. Tajuddin b.M. Ali, Mr. P. Gopal, Mr. R. Dungan and Mrs. C. Weinrichter is gratefully acknowledged 相似文献
50.