共查询到20条相似文献,搜索用时 15 毫秒
1.
M. V. D'Auria L. Minale R. Riccio E. Uriarte 《Cellular and molecular life sciences : CMLS》1988,44(8):719-720
Summary The first isolation of 8-(R)-hydroxy-5Z, 9E, 11Z, 14Z-eicosatetraenoic acid [8-(R)-HETE] from a marine source, the pacific starfishPatiria miniata, is reported. 8-(R)-HETE occurs together with 8-(R)-hydroxy-5Z, 9E, 11Z, 14Z, 17Z-eicosapentaenoic acid. 相似文献
2.
海洋弧菌多样性 总被引:2,自引:0,他引:2
海洋弧菌泛指异营性、好盐性、兼性嫌气性革兰氏阴性杆菌中,具有发酵葡萄糖等醣类能力者。它们遍布于内湾、沿岸和大洋水域及海底沉积物,也遍布于形形色色海洋生物体表和体内。这类细菌中,有少数种类是海洋鱼类和无脊椎动物特化发光器官内共生者,另有许多其它种类是人类和海洋动物病原体。海洋弧茵具有各类物质分解能力,包括能降解几丁质、洋菜等复杂多醣类,因而可能在沿岸环境有机物质循环再生中,扮演重要角色。这类细菌的固氮作用,可能是海洋环境中氨态氮重要来源之一。16S rDNA序列之亲源分析显示,海洋弧菌隶属γ-Proteobacteria。七十多种海洋弧菌目前被归类于Enreovibrio、Grimontia、Photobacterium、Salinovibrio和Vibrio五属;前两属属于Enterovibrionaceae,后三属分别属于Photobacteriaceae、Salinovibrionaceae和Vibrionaceae。利用限制型分析于区分16S rDNA基因型,是一种简易快速,而又有效于遂行海洋弧菌分离株初步分类的方法。 相似文献
3.
Summary Ricinoleic acid was found in differentClaviceps sp., indicating that it is neither specific chemotaxonomic marker ofClaviceps purpurea, nor a specific indicator of peptide alkaloid synthesis. 相似文献
4.
主要国家海洋天然气水合物研发现状及我国对策 总被引:1,自引:0,他引:1
本文概述了若干主要国家海洋天然气水舍物研发近况.在回顾我国研发现状和国情分析的基础上,有针对性地提出了进一步加强顶层设计、构建研发体系、加大试采研究、促进成果转化力度、探索商业化运作模式及加强国际合作六个方面的推动性政策建议,供决策部门参考. 相似文献
5.
The polyunsaturated fatty acids (PUFAs), linoleic acid (LA), alpha linolenic acid (ALA), gamma linolenic acid (GLA), arachidonic acid (AA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), showed inhibition of growth of both normal and abnormal (Molt-4) human lymphocytes, and inhibition was concentration-dependent. Interestingly, the production of the lymphokine Interleukin-2 (IL-2) was elevated in Molt-4 cells, but it was reduced in the normal human lymphocytes. Addition of GLA or IL-2 or a combination of both showed enhancement of SO
2
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and of lipid peroxidation levels, which were significantly higher in Molt-4 cells than in the normal lymphocytes. Reduction of protein concentration was also observed in both types of cells during this treatment. The data showed that the antiproliferative effects of GLA and IL-2 may partly be exerted through the elevated production of superoxide free radicals and peroxidatin products. This is a novel finding and therefore, further exploitation of combinations of PUFAs and IL-2 may be a possible way of combating cancer cell growth. 相似文献
6.
Tryptophan is converted to 5-hydroxytryptamine (5-HT) in the brain and evidence is presented that an increase in the concentration of 5-HT can result in physical and mental fatigue during prolonged exercise. The entry of tryptophan in the brain is influenced by the plasma level of free tryptophan (that not bound to albumin) and, from competition for entry into brain, by the plasma level of branched chain amino acids. Hence, oral administration of branched chain amino acids could, theoretically, prevent the increase in 5-HT level during exercise and therefore delay physical and mental fatigue. Evidence in support of this hypothesis is presented. 相似文献
7.
J. Maruyama T. Noguchi J. K. Jeon T. Harada K. Hashimoto 《Cellular and molecular life sciences : CMLS》1984,40(12):1395-1396
Summary A toxin causing paralysis was detected in the starfishAstropecten latespinosus. The toxin was purified by a method consisting of charcoal treatment and chromatography on CM-Sephadex C-25 and Bio-Rex 70. The toxin was identified as tetrodotoxin by its behavior in thin-layer chromatography and electrophoresis and its1H-NMR spectrum.Acknowledgment. This work was in part supported by a research fund from the Ministry of Agriculture, Forestry and Fisheries of Japan. 相似文献
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H. Tabata T. Hasegawa M. Nakagoshi S. Takikawa M. Tsusue 《Cellular and molecular life sciences : CMLS》1996,52(1):85-87
A blue fluorescent compound was isolated fromMorpho butterfly wings. Based on thin layer chromatographic, UV and CD-spectrophotometric and HPLC analyses, the blue fluorescent compound was identified as L-erythro biopterin. Biopterin is a major component of blue fluorescent pteridines in bothM. sulkowskyi andM. adonis. Pterin and isoxanthopterin can also be detected as minor components in these species. This paper is the first to report the presence of biopterin in butterfly wings. 相似文献
10.
V. Erspamer G. Bertaccini J. M. Cei 《Cellular and molecular life sciences : CMLS》1962,18(12):563-564
Riassunto Gli estrati di pelle di alcuni comuni anfibi nostrani (Rana esculenta, Rana temporaria) e, ancor più, di certi anfibi sudamericani del generePhyllomedusa contengono rilevanti quantitativi di polipeptidi bradichinino-simili. Negli estratti diPhyllomedusa sauvagi ne sono stati identificati almeno tre, a mezzo di una semplice cromatografia su colonna di allumina basica: polipeptide A, assai simile alla bradichinina per le sue proprietà farmacologiche; polipeptide B, dotato di prolungata ed intensa azione ipotensiva; polipeptide C, particolarmente attivo sull'ileo di cavia. Sono in corso ricerche dirette all'isolamento di questi polipeptidi e al chiarimento della loro struttura chimica.
Supported by grants from the Consiglio Nazionale delle Ricerche, Roma, and the Rockefeller Foundation, New York. 相似文献
Supported by grants from the Consiglio Nazionale delle Ricerche, Roma, and the Rockefeller Foundation, New York. 相似文献
11.
Summary Visual pigment regeneration in the frog requires apposition between the retina and retinal pigment epithelium. However, regeneration occurs nearly as well with the retina upside down (i.e. with the inner limiting membrane facing the pigment epithelium) as right side up.Acknowledgments. Supported in part by the Medical Research Service of the Veterans Administration and National Eye Institute Grant EY-01678. 相似文献
12.
V. Agnihothrudu 《Cellular and molecular life sciences : CMLS》1956,12(4):149-150
Zusammenfassung Sechs Arten von Dictycosteliaceae sind in Indien zum ersten Mal aus bebautem und unbebautem Boden isoliert worden. Ihr Vorkommen in nichtkultivierten Böden war bis jetzt unbekannt. Die Rhizosphäre der Pflanzen scheint ein wichtiges Habitat dieser Organismen zu sein. 相似文献
13.
D. Thiéry B. Gabel P. Farkas V. Pronier 《Cellular and molecular life sciences : CMLS》1992,48(7):697-699
The oviposition of the European grapevine moth (EGVM)Lobesia botrana can be deterred by an extract of conspecific eggs corresponding to 20 egg equivalents. The reduction of the oviposition behavior is dose-dependent. Nine chemicals have been extracted from the eggs and identified as straight chain fatty acids and esters of fatty acids. A mixture of these rather simple molecules induces the same levels of deterrence as the total extract. It might be possible to use oviposition regulating pheromone in the future for the control of EGVM populations. 相似文献
14.
G. Cimino A. Crispino V. Di Marzo G. Sodano A. Spinella G. Villani 《Cellular and molecular life sciences : CMLS》1991,47(1):56-60
Summary Prostaglandin-(PG) 1,15-lactones and, in smaller amounts, free acids, were isolated from both the mantle and the dorso-lateral appendices of the opisthobranch molluscTethys fimbria. In vivo conversion of PGs into the corresponding lactones and accumulation of PGE2- and PGE3-1,15-lactones in the appendages were shown. The detachment of these appendages from the molested mollusc caused the in vivo conversion of PGE2- and PGE3-lactones back to PGE2 and PGE3 respectively, thus providing the first example of a mechanism by which prostaglandins can be stored and, when needed, released. 相似文献
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16.
E. Katchalski-Katzir 《Cellular and molecular life sciences : CMLS》1997,53(10):780-789
During the 1950s, linear and multichain poly-α-amino acids were synthesized by polymerization of the corresponding N-carboxyamino acid anhydrides in solution in the presence
of suitable catalysts. The resulting homo- and heteropolymers have since been widely employed as simple protein models. Under
appropriate conditions, poly-α-amino acids, in the solid state and in solution, were found to acquire conformations of an α-helix and of β-parallel and antiparallel pleated sheets, or to exist as random coils. Their use in experimental and theoretical investigations
of helix-coil transitions helped to shed new light on the mechanisms involved in protein denaturation. Conformational fluctuations
of peptides in solution were analysed theoretically and studied experimentally by nonradiative energy-transfer techniques.
Poly-α-amino acids played an important role in the deciphering of the genetic code. In addition, analysis of the antigenicity of
poly-α-amino acids led to the elucidation of the factors determining the antigenicity of proteins and peptides. The synthetic procedures
developed made possible the preparation of immobilized enzymes which were shown to be of considerable use as heterogeneous
biocatalysts in the chemical and pharmaceutical industry. Interest in the biological and physicochemical characteristics of
poly-α-amino acids was recently renewed because of the reported novel findings that some copolymers of amino acids are effective
as drugs in multiple sclerosis, and that glutamine repeats and reiteration of other amino acids occur in inherited neurodegenerative
diseases. 相似文献
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Resumé Un taux faible d'insuline immunoréactive (IRI) et d'activité semblable à l'insuline (ILA) a été décelé dans la muqueuse duodénale du rat, mais non pas dans celles du lapin, du chat et du chien. Les autres régions du tractus digestif de toutes ces expèces présentaient un taux extrèmement bas d'insuline. Le traitement par l'alloxane entraîne le vidage de l'IRI et l'ILA duodénales. 相似文献
19.
Résumé Une hypothèse est présentée pour expliquer la variabilité en durée de la période préléthargique au cours de l'année. La période préléthargique pouvait être approximée à trois mois. Dès novembre, le Hamster développe une prédisposition, résultant dans un raccourcissement de la période préléthargique. En février, la prédisposition pour le sommeil hivernal est au maximum, mais ensuite elle est perdue. 相似文献
20.
J. N. Medda J. Nandi D. Roy S. Ghosh T. Moitra A. Bhowmick 《Cellular and molecular life sciences : CMLS》1984,40(9):986-988
Summary Increase in nuclear size in liver has been used as an index of polyploidy. It has long been considered that the occurrence of polyploidy and multinuclearity are characteristics of mammalian liver. The present study shows the occurrence of these phenomena in the liver of birds, so these features are not confined to mammals. 3 classes of nuclear size groups have been identified. The simultaneous occurrence of polyploidy and binuclearity indicates some sort of interrelationship between them. 相似文献