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1.
Methacholine, nicotine and succinylcholine stimulated the phospholipase A2-acylation system of synaptic membranes isolated from the cerebral cortex of guinea pig. Stimulation by acetylcholine was partially blocked by atropine and by D-tuberocurarine respectively, indicating both muscarinic and nicotinic stimulation. Muscarinic stimulation by acetylcholine was greater than -isotinic stimulation, and stimulation by acetylcholine was completely blocked by a combip, or;. and n-tuberocurarine. The phospholipase A2-acylat tem was stimulated by phenylcphrine., id. Cqxoterenoi. Stimulation by noradrenaline was J-. tidlr, by phenoxybenzamine and pindalol i:spectively, indicating both 8-adrenergic and P-adrenergic ztimulation. n-Adrenergic stimulation by noradrenaline was greater than P-adrenergic-stimulation. 5 -mlation by noradrenaline was completely blocked by a combination of phenoxybenzamins and pindalol. Stimulation of both acylation and phospholipid hydrolysis, by 5-hydroxytryptamine and histamine were partially blocked by methysergide and diphenhydramine respectively. Stimulation by dopamine was blocked by halopcridol. Stimulation by y-aminobutyric acid was partially blocked by strychnine and by picrotoxin. Dichloroisoproterenol, atropine, methysergidr, diphenhydramine, strychnine, picrotoxin and eserine, at relatively high concentrations (1 mM), stimuhted the phospholipase A2-acylation system. Synergistic stimulations of both acylatior, and hydrolysis of phosphatidylcholine, were observed by adenosine combined with noradrenaline, 5-hydroxytryptamine, histamine, dopamine or yaminobutyric acid, respectively. In the presence of ATP-MgCI, synergistic stimulations of the hydrolysis of phosphatidyicholine were observed after 30 s by noradrenaline combined with 5-hydroxytryptamine, histamine, dopamine, aminobutyric acid or carbamoylcholine respectively. In the presence of GTP-MgC12 synergistic stimulations were obtained by cdrbamoylcholine combined with noradrenaline. 5-hydroxytryptamine. histamine, dopamine or y-aminobutyric acid, respectively. In the presence of ATP-MgC12 plus GTP-MgC12, stimulation by noradrenaline and one other agonist including 5-hydroxytryptamine, histamine, dopamine, y-aminobutyric acid or carbamoylcholine were close to additive.  相似文献   

2.
Book reviewed in this article:
The Voyage of Charles Darwin: His Autobiographical writings, selected and arranged by Christopher Railing.
Penguin Nature Guides: Fungi of Northern Europe, Vols I & II, by S. Nilsson &; O. Persson; illustrated by B. Mossberg
Penguin Nature Guides: Plant Communities, by Anned Biilow-Olsen, illustrated by Susanne Larsen; translated from the Danish by Joan Tate; edited and adapted by Francis Rose.
Penguin Nature Guides: Fishes of the British and Northern European Seas, by J. Moller Christensen; illustrated by Bente Nystrom; translated from the Danish by Gwynne Vevers; edited and adapted by Gwynne Vevers and Philip Orkin.
Birds of Wood, Park and Garden, text and illustrations by Lars Jonsson; translated from the Swedish by Roger Tanner
Birds of Sea and Coast, text and illustrations by Lars Jonsson; translated from the Swedish by Roger Tanner  相似文献   

3.
The sensitivities of apoptosis induced by E1A, c-Myc, Bax, and Nip3 to wild-type (wt) and mutated p53 and Id proteins were analyzed by transient transfection followed by flow cytometry with p53 null mouse cerebellum cell lines W7 and M13 that express wt and mutated p53 in response to dexamethasone, respectively. Apoptosis induced by c-Myc was stimulated weakly by wt p53, strongly by Ids, but suppressed completely by mutated p53 irrespective of coexpression with Ids, while apoptosis induced by E1A was suppressed by mutated p53 but stimulated when coexpressed with Ids. Apoptosis induced by Bax was little affected by wt and mutated p53, but inhibited by Ids, while apoptosis induced by Nip3 was inhibited by both wt and mutated p53 and inhibition was stimulated by Ids. Caspase-1 was activated only by Bax significantly when coexpressed with mutated p53 but not with wt p53. These results indicate that the apoptotic processes elicited by these inducers are different and differently affected by wt and mutated p53 and by Ids.  相似文献   

4.
Taxonomy of Economic Seaweeds with Reference to some Pacific and Western Atlantic Species, Volume 3, edited by Isabella A. Abbott
Conservation of Medicinal Plants edited by Olayiwola Akerele, Vernon Heywood & Hugh Synge
Introduction to Floriculture, 2nd Ed., edited by R. A. Larson
Plant Membranes: A Biophysical Approach to Structure, Development and Senescence by Ya'acov Y. Leshem
The Ecology o/Fynbos, edited by R. Cowling
A Dictionary of Plant Pathology, by P. Holliday
7th International Exhibition of Botanical Art and Illustration 13 April to 31 July 1992. Catalogue by James J. White & Autumn M. Farole
Plant Growth: interactions with nutrition and environment, edited by J. R. Porter & D. W. Lawlor
Response of Plants to Multiple Stresses, edited by H. A. Mooney, W. E. Winner & E. J. Pell
Pollen and Spores: Patterns of Diversification, edited by S. Blackmore and S. H. Barnes
International Checklist for Hyacinths and Miscellaneous Bulbs, edited by J. van Scheepen
Atlas Florae Europaeae, 9 (Paeoniaceae to Capparaceae), edited by Jaakko Jalas & Juha Suominen
Nitrogen fixation, edited by M. Polsinelli, R. Materassi & M. Vincenzini
Crucifers of Great Britain and Ireland, by T.C.G. Rich
Micropropagation: Technology and Application, edited by P. C. Debergh & R. H. Zimmerman
Phytochemical Induction by Herbivores, edited by D. W. Tallamy & M. J. Raupp
Pattern Formation in Plant Tissues, by T. Sachs
Introduction to the Principles of Plant Taxonomy, 2nd ed, by V. V. Sivarajan (edited by N. K. B. Robson)
Signal Perception and Transduction in Higher Plants, edited by R. Ranjeva & A. M. Boudet
Plant Growth Substances 1988, edited by R. P. Pharis & S. B. Rood
Gibberellins, edited by N. Takahashi, B.O. Phinney & J. MacMillan  相似文献   

5.
Book reviewed in this article:
Flowers of the Himalaya , by Oleg Polunin and Adam Stainton.
A Guide to the Vegetation of Britain and Europe , by Oleg Polunin and Martin Walters.
The Experimental Biology of Bryophytes, edited by A. F. Dyer & J. G. Duckett.
A Birdwatcher's Miscellany, edited by Rob Hume.
The Moths and Butterjlies of Great Britain and Ireland, Volume 10, Noctuidae (Part II) and Agaristidae, edited by J. Heath.
Atlas of Butterjlies in Britain and Ireland, by J. Heath, E. Pollard & J. A. Thomas.
Colour Identification Guide to Butterjlies of the British Isles, revised edition by T. G. Howarth.
The World of Butterjlies, An Illustrated Encyclopaedia, by V. Sbordoni & S.Forestiero.
Colour Identijcation Guide to Moths of the British Isles, by Bernard Skinner.
The Biology of Buttegies, edited by R. I. Vane-Wright & P. R. Ackery.
Australian Grasses, by Nancy T. Burbidge, revised by Surrey W. L. Jacobs.
Collins Guide to Grasses, Sedges, Rushes and Ferns, by R. Fitter & A. Fitter. Collins.
Grasses of the Soviet Union, by N. N. Tsvelev, edited by A. A. Fedorov.
The European Garden Flora, Volume 2, Monocotyledons (Part ZZ), edited by S. M Walters et al.
Grasses, 3rd edition, by C. E. Hubbard, revised by J. C. E. Hubbard.  相似文献   

6.
Metallothionein inhibits peroxynitrite-induced DNA and lipoprotein damage   总被引:13,自引:0,他引:13  
Previous studies have demonstrated that metallothionein functions as an antioxidant that protects against oxidative DNA, protein, and lipid damage induced by superoxide anion, hydrogen peroxide, hydroxyl radical, and nitric oxide. The present study was undertaken to test the hypothesis that metallothionein also protects from DNA and lipoprotein damage induced by peroxynitrite, an important reactive nitrogen species that causes a diversity of pathological processes. A cell-free system was used. DNA damage was detected by the mobility of plasmid DNA in electrophoresis. Oxidation of low density lipoprotein was measured by a thiobarbituric acid-reactive substance, which was confirmed by lipid hydroperoxide assay. Plasmid DNA damage and low density lipoprotein oxidation were induced by 3-morpholinosydnomine, which produces peroxynitrite through the reaction between nitric oxide and superoxide anion or by synthesized peroxynitrite directly. DNA damage by 3-morpholinosydnomine was prevented by both metallothionein and superoxide dismutase, whereas the damage caused by peroxynitrite was prevented by metallothionein only. The oxidation of low density lipoprotein by 3-morpholinosydnomine and peroxynitrite was also significantly inhibited by metallothionein. This study thus demonstrates that metallothionein may react directly with peroxynitrite to prevent DNA and lipoprotein damage induced by this pathological reactive nitrogen species.  相似文献   

7.
Inducible binding proteins for C4-dicarboxylic acids (DBP) and glucose (GBP) were isolated from Pseudomonas aeruginosa by extraction of exponential-phase cells with 0.2 M MgC12 (pH 8.5) and by an osmotic shock procedure without affecting cell viability. DBP synthesis was induced by growth on aspartate, alpha-ketoglutarate, succinate, fumarate, malate, and malonate but not by growth on acetate, citrate, pyruvate, or glucose. Binding of succinate by DBP was competitively inhibited by 10-fold concentrations of fumarate and malate but not by a variety of related substances. GBP synthesis and transport of methyl alpha-glucoside by whole cells were induced by growth on glucose or pyruvate plus galactose, 2-deoxyglucose, or methyl alpha-glucoside but not by growth on gluconate, succinate, acetate, or pyruvate. The binding of radioactive glucose by GBP was significantly inhibited by 10-fold concentrations of glucose, galactose, and glucose-1-phosphate but not by the other carbohydrates tested. The binding of glucose by GBP or succinate by DBP did not result in any chemical alteration of the substrates.  相似文献   

8.
Intact cells of the marine bacterium Alteromonas haloplanktis 214 oxidized NADH, added to the suspending medium, by a process which was stimulated by Na+ or Li+ but not K+. Toluene-treated cells oxidized NADH at three times the rate of untreated cells by a mechanism activated by Na+ but not by Li+ or K+. In the latter reaction, K+ spared the requirement for Na+. Intact cells of A. haloplanktis oxidized ethanol by a mechanism stimulated by either Na+ or Li+. The uptake of alpha-aminoisobutyric acid by intact cells of A. haloplanktis in the presence of either NADH or ethanol as an oxidizable substrate required Na+, and neither Li+ nor K+ could replace it. The results indicate that exogenous and endogenous NADH and ethanol are oxidized by A. haloplanktis by processes distinguishable from one another by their requirements for alkali metal ions and from the ion requirements for membrane transport. Intact cells of Vibrio natriegens and Photobacterium phosphoreum oxidized NADH, added externally, by an Na+-activated process, and intact cells of Vibrio fischeri oxidized NADH, added externally, by a K+-activated process. Toluene treatment caused the cells of all three organisms to oxidize NADH at much faster rates than untreated cells by mechanisms which were activated by Na+ and spared by K+.  相似文献   

9.
We examined by using 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) as a radical generator the ability of estrogens to scavenge carbon-centered and peroxyl radicals. Electron spin resonance signals of carbon-centered radicals from AAPH were diminished by catecholestrogens but not by phenolic estrogens, showing that catecholestrogens efficiently scavenged carbon-centered radicals. However, fluorescent decomposition of R-phycoerythrin by AAPH-derived peroxyl radicals was inhibited by catecholestrogens and phenolic estrogens. Evidently, peroxyl radicals were scavenged by catecholestrogens and by phenolic estrogens. However, the scavenging ability of 4-hydroxyestradiol was less than 2-hydroxyestradiol. Strand break of DNA induced by AAPH was inhibited by catecholestrogens, but not by phenolic estrogens under aerobic and anaerobic conditions. Inactivation of lysozyme induced by AAPH was completely blocked by 2-hydroxyestradiol under aerobic and anaerobic conditions, and by 4-hyroxyestradiol only under anaerobic conditions. Peroxidation of arachidonic acid by AAPH was strongly inhibited by catecholestrogens at low concentrations. Only large amounts of phenolic estrogens markedly inhibited lipid peroxidation. These results show that catecholestrogens were antioxidant against AAPH-induced damage to biological molecules through scavenging both carbon-centered and peroxyl radicals, but phenolic estrogens partially inhibited AAPH-induced damage because they scavenged only peroxyl radicals.  相似文献   

10.
Book reviewed in this article:
A World Like Our Own—Man and Nature in Madagascar , by Alison Jolly.
Vertebrate Limb Regeneration , by H. Wallace.
Statistical Methods in Biology , by N. T.J. Bailey
Conservation and Evolution , by O. H. Frankel & M. E. Soule
Evolution in Age-structured Populations by B. Charlesworth
Essential Biology , by Herbert T. Hendrickson
Flora Suzakiensis , edited by Biological Laboratory, Imperial Household
Phylogenetic Patterns and the Evolutionary Process , by N. Eldredge & J. Cracraft
Excursion Flora of the British Isles , by A. R. Clapham, T. G. Tutin & E. F. Warburg
Whales , by W. N. Bonner
Les Chevaux, Fossiles et Actuels , by V. Eisenmann
Freshwater Snails of Africa and their Medical Importance , by David S. Brown
Symbiosis in Cell Evolution , by Lynn Margulis
Vegetation Dynamics , by J. Miles  相似文献   

11.
Book reviewed in this article:
Synopsis and Classification of Living Organisms , by Sybil P. Parker
The Natterjack Toad , by Trevor J. C. Beebee
Seals of the World , by Judith E. King.
British Hoverflies , by A. E. Stubbs and S. J. Falk.
Handbook of Microscopy , by Marcel Locquin and Maurice Langeron.
Global Marine Pollution Bibliography. Ocean Dumping of Municipal and Industrial Wastes , by Michael A. Champ and P. Kilho Park.
Animal Language , by M. Bright.
Modelling Fluctuating Populations , by R. M. Nisbet and W. S. C. Gurney.
Plant-Atmosphere Relationships , by J. Grace.
Wetland Ecology , by J. R. Etherington
The Role of Fire in Northern Circumpolar Ecosystems (SCOPE 18), edited by R. W. Wein and D. A. Maclean. John Wiley and Sons  相似文献   

12.
In a laboratory study, indica and japonica rice (Oryza sativa L.) seeds were exposed to thermal hardening (heating followed by chilling followed by heating; chilling followed by heating followed by chilling; heating followed by chilling or chilling followed by heating). In indica rice, heating followed by chilling followed by heating resulted in decreased mean germination time, time to start germination, electrical conductivity of seed leachates, and time to 50% germination, as well as increased germination index, energy of germination, radicle and plumule length, root length, root/shoot ratio, root fresh and dry weight, radicle and plumule growth rate, and shoot fresh weight. In japonica rice, chilling followed by heating followed by chilling performed better than all other treatments, including control.  相似文献   

13.
Book reviewed in this article:
Taxonomy of Economic Seaweeds: With reference to some Pacific and Caribbean Species, 2 edited by Isabella A. Abbott. La Jolla
Botanic Gardens and the World Conservation Strategy edited by D. Bramwell, O. Hamann, V. Heywood & H. Synge
Introduction to Ecological Biochemistry 3rd ed., by J. B. Harborne
A monographic study of the genus Rosularia (Crassulaceae) by Urs Eggli
The Photographic Guide to Identify Mediterranean Wild Flowers by Roger Phillips assisted by Martin Rix and Nicky Fox
The Photographic Guide to Identify Mediterranean Wild Flowers by Roger Phillips assisted by Martin Rix and Nicky Fox
Conserving the Wild Relatives of Crops by Erich Hoyt.
Somatic Cell Genetics of Woody Plants edited by M. R. Ahuja
Indian Journal of Natural Rubber Research
Dictionary of Weeds of Eastern Europe by G. Williams and K. Hunyadi
Nutrition of the Angiosperm Embryo by David R. Murray.
Plant Pigments edited by T. W. Goodwin.
Panbiogeography edited by R. Craw & G. Sermonti
Saxifrages of Europe: with notes on African, American and some Asiatic species by D. A. Webb & R. J. Gornall  相似文献   

14.
Formaldehyde can be metabolized primarily by two different pathways, one involving oxidation by the low-Km mitochondrial aldehyde dehydrogenase, the other involving a specific, glutathione-dependent, formaldehyde dehydrogenase. To estimate the roles played by each enzyme in formaldehyde metabolism by rat hepatocytes, experiments with acetaldehyde and cyanamide, a potent inhibitor of the low-Km aldehyde dehydrogenase were carried out. The glutathione-dependent oxidation of formaldehyde by 100,000g rat liver supernatant fractions was not affected by either acetaldehyde or by cyanamide. By contrast, the uptake of formaldehyde by intact mitochondria was inhibited 75 to 90% by cyanamide. Acetaldehyde inhibited the uptake of formaldehyde by mitochondria in a competitive fashion. Formaldehyde was a weak inhibitor of the oxidation of acetaldehyde by mitochondria, suggesting that, relative to formaldehyde, acetaldehyde was a preferred substrate. In isolated hepatocytes, cyanamide, which inhibited the oxidation of acetaldehyde by 75 to 90%, produced only 30 to 50% inhibition of formaldehyde uptake by cells as well as of the production of 14CO2 and of formate from [14C]formaldehyde. The extent of inhibition by cyanamide was the same as that produced by acetaldehyde (30-40%). In the presence of cyanamide, acetaldehyde was no longer inhibitory, suggesting that acetaldehyde and cyanamide may act at the same site(s) and inhibit the same formaldehyde-oxidizing enzyme system. These results suggest that, in rat hepatocytes, formaldehyde is oxidized by cyanamide- and acetaldehyde-sensitive (low-Km aldehyde dehydrogenase) and insensitive (formaldehyde dehydrogenase) reactions, and that both enzymes appear to contribute about equally toward the overall metabolism of formaldehyde.  相似文献   

15.
Book reviewed in this article:
The Genus Utricularia, by Peter Taylor.
Tropical Woody Rubiaceae. Characteristic features and progressions. Contributions to a new subfamial classification, by Elmar Robbrecht.
Bracken Biology and Managment, edited by J. A. Thomson and R. T. Smith.
How to Know Western Australian Wildflowers, Part I, by W. E. Blackall and B. J. Grieve.
Flora of the East Riding of Yorkshire, by Eva Crackles.
Flower Artists of Kew, Botanical Paintings by Contemporary Artists, by William T. Stearn.
The Liverworts of Britain and Ireland, by A.J. E. Smith.
Competition, by P. A. Keddy.
Origin of Cultivated Rice, by H. I. Oka.
The Impact of Biotechnology on Agriculture, edited by R. S. Sangwan and B. S. Sangwan-Norreel.  相似文献   

16.
植物生长调节物质IP-1号对木薯产量及其生物性状的影响   总被引:4,自引:0,他引:4  
1990和1991年在木薯(ManihotesculentaCrantz)生长期以植物生长调节物质IP-1号0,20,30和40ppm进行叶面喷洒,结果表明:30ppm处理可使木薯块根产量平均增加54.44%,块根淀粉含量平均提高20.81%。单株最大薯重提高31.55%,块根数增加21.17%,块根长度增长17.62%,地上部鲜重增加34.36%,植株高度增加4.36%,植株收获期保留青叶数增加19.42%,主茎直径增加6.26%,块根直径增加2.58%,叶片的叶绿素和蛋白质含量分别提高5.57%和25.96%,叶片光合作用强度提高15.86%,而对主茎高度、主茎节数没有明显影响。  相似文献   

17.
The purpose of this study was to compare the accuracy, precision, and bias of fat mass (FM) as assessed by dual-energy X-ray absorptiometry (DXA), hydrostatic weighing (HW), air-displacement plethysmography (PM) using the BOD POD body composition system and total body water (TBW) against the four-compartment (4C) model in 25 children (11.4 +/- 1.4 yr). The regression between FM by the 4C model and by DXA deviated significantly from the line of identity (FM by 4C model = 0.84 x FM by DXA + 0.95 kg; R(2) = 0.95), as did the regression between FM by 4C model and by TBW (FM by 4C model = 0. 85 x FM by TBW - 0.89 kg; R(2) = 0.98). The regression between FM by the 4C model and by HW did not significantly deviate from the line of identity (FM by 4C model = 1.09 x FM by HW + 0.94 kg; R(2) = 0. 95) and neither did the regression between FM by 4C (using density assessed by PM) and by PM (FM by 4C model = 1.03 x FM by PM + 0.88; R(2) = 0.97). DXA, HW, and TBW all showed a bias in the estimate of FM, but there was no bias for PM. In conclusion, PM was the only technique that could accurately, precisely, and without bias estimate FM in 9- to 14-yr-old children.  相似文献   

18.
Book reviewed in this article:
The Mature and Origin of the Biological World, by E. J. Ambrose
An unusual newly discovered Archosauer from the Upper Triassic of Virginia USA, by R.E. Weems
The Biology of Nectaries, edited by B. Bentley and T. Elias
Animal Taxonomy, by H. E. Goto
Diets for Birds in Captivity by K. C. Lint & A. M. Lint
Lizards of Western Australia I. Skinks, by G. M. Storr, L. A. Smith & R. E. Johnstone
Advances in Legume Systematics, edited by R. M. Polhill & P. H. Raven
Tuberous, Cormous and Bulbous Plants, by J. S. Pate and K. W. Dixon
Evolution and the Theory of Games, by John Maynard Smith
Sound and Hearing, by Martin E. Rosenberg
Differential Equations and Applications in Ecology, Epidemics and Population Problems, edited by S. N. Busenberg & K. L. Cooke
Plant Pathology and Plant Pathogens, (2nd Edition), by Colin Dickinson & John Lucas
A Complete Guide to British Butterflies, by Margaret Brooks & Charles Knight  相似文献   

19.
Book reviewed in this article:
Life Among the Scientists. An anthropological study of an Australian scientific community, by Max Charlesworth, Lyndsay Farrall, Terry Stokes and David Turnbull.
Carnivore Behaviour, Ecology and Evolution, edited by John L. Gittleman.
Oxford Surveys in Evolutionary Biology, Volume 6, edited by P. H. Harvey and L. Partridge.
The Malay Archipelago, by Alfred Russel Wallace, with an introduction by John Bastin.
Microbial Products: New Approaches, edited by S. Baumberg, I. S. Hunter & M. Rhodes.
Life at the Edge: Readings from Scientific American Magazine, edited by James L. Gould and Carol L. Gould.
Theoretical Population Genetics, by J. S. Gale.
Speciation and its Consequences, edited by Daniel Otte and John A. Endler.
Island Africa, The Evolution of Africa's Rare Animals and Plants, by Jonathan Kingdon.  相似文献   

20.
Book reviewed in this article:
Ecophysiology of the Camelidae and Desert Ruminants, by Richard T. Wilson
Paleontology of Vertebrates, by Jean Chaline
The Tettigoniidae: Biology, Systematics and Evolution, edited by W. T. Bailey and D. C. F. Rentz
Behaviour of Pinnipeds, edited by D. Renouf
Chemical Signals in Vertebrates 5, edited by D. W. Macdonald, D. Muller-Schwarze and S. E. Natynczuk
The Butterflies of Great Britain and Ireland (Hesperiidae to Nymphalidae), edited by A. Maitland Emmet & the late John Heath
Heterotypical Behaviour in Man and Animals, edited by M. Haug, P. F. Brain and C. Aron
Insect Life Cycles, Genetics, Evolution and Co-ordination, edited by F. Gilbert.
Grasshoppers and Allied Insects of Great Britain and Ireland, by J. A. Marshall and E. C. M. Haes  相似文献   

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