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1.
Wang Renxue Wu Xianhan Zhou Jing Zhang Shicui Ma Yingjie Wu Shangqin Shi Yingxian 《中国海洋湖沼学报》1991,9(1):88-93
Full maturation of goldfish oocyte was inducedin vitro by 17 α-hydroxy-20β-dihydroprogesterone. The oocyte maturation involves GV migration to the periphery of the oocyte and germinal
vesicle breakdown (GVBD). In the experiment, incubation duration for GVBD varied in different broods of oocytes. Generally,
if the duration for GVBD was shorter than 6 h, oocytes would have a better chance to survive after maturation and insemination.
The maturation of nucleus (GV) and cytoplasm are not synchronous. Cytoplasm maturation occurs several hs after GVBD. Oocytes
inseminated 8–9 h after GVBD have the highest fertilizing and hatching rate. Fertilized ova maturedin vitro can develop to sexually mature adults capable of reproduction.
Contribution No 1731 from the Institute of Oceanology, Academia Sinica. 相似文献
2.
The profiles of cortisol, testosterone, ll-ketotestosterone and 17α， 20β- dihydroxy-4-pregnene-3-one in mule rainbow trout reared under constant water temperature and natural photoperiod were determined by radioimmunoassay. Gonads of male rainbow trout reached maturity when the fish were two years old. Changes in the plasma levels of both sex steroid hormones and cortisol were closely related to the GSI. Plasma levels of testosterone, 11-ketotestostemne and 17a, 2013-dihydroxy 4-pregnene-3-one showed a clear peak in the annual breeding season, when the GSI reached their maxima. Plasma cortisol levels also showed clearly seasonal changes in both two- and three-year-old fish. The results suggest that the elevated plasma levels of cortisol may not just be due to stresses during the breeding season but have certain physiological functions in the reproduction of rainbow trout. 相似文献
3.
R-phycoerythrin fromPorphyra haitanensis exists in two aggregation states with different molecular weights. A more highly aggregated form, RPE I, was chromatographed
on Bio-Rex 70 column with urea solution (pH 3.0) as eluent, and the molecular weights of the 3 subunits (α, β, γ) obtained
were determined on SDS-PAGE at 18000, 19200 and 30000, respectively. α subunit carried two phycoerythrobilin (PEB); β subunit,
three PEB and one phycourobilin (PUB); γ subunit, one PEB and three PUB chromophores. The molar ratio of α, β, and γ subunits
of RPE I was 6: 6: 1, and their subunit composition was confired to be (αβ)6γ on account of the molecular weight of RPE I, 232000.
A lower aggregated form, RPE II, contained α and β subunits similar to those of RPE I, but its subunit composition was the
(αβ) monomer of RPE.
Contribution No. 2108 from the Institute of Oceanology, Chinese Academy of Sciences 相似文献
4.
Six steroids have been isolated from ethanolic extract of green alga Chaetomorpha basiretorsa Setchell by a combination of repeated normal phase silica gel and Sephadex LH-20 gel column chromatography as well as recrystallization. Using spectroscopic methods including MS and NMR, their structures were determined as β-1awsaritol （1）, saringosterol （2）, 24-hydroperoxy-24-vinyl- cholesterol （3）, β-stigmasterol （4）, stigmast-4-en-3α, 6β-diol （5）, 29-hydroxystigmasta-5, 24 （28）-dien-3β-ol （6）. All these compounds were obtained from this genus for the first time and they were inactive （IC50〉10μg/ml） against KB, Bel-7402, PC-3M, Ketr 3 and MCF-7 cell lines. 相似文献
5.
1-methladenine (1-MA) induces starfish oocytes maturation via surface reaction followed by the appearance of a cytoplasmic
maturation factor which in turn induces germinal vesicle breakdown (GVBD) to resume meiosis. Cellular mechanisms involved
in GVBD were investigated by microinjection of metabolic inhibitors. Colchicine (Co) inhibited maturation, cytochalasin-B
(CB) delayed GVBD and actinomycin-D-(Act-D) and puromycin (Pu) had no effect. It appears that the microtubule and the microfilament
systems are associated with the nuclear membrane dissolution during the process of oocyte maturation of starfish. 相似文献
6.
A new ketosteroid, along with six known steroids, was isolated from the ethanolic extracts of red alga Acanthophora spicifera (Vahl.) Boergesen. The structures, identified using chemical and spectroscopic methods including 2D NMR, were: (1) 22-hydroxy-5α-cholest-3,6-dione, (2) 6-hydroxycholest-4-ene-3-one, (3) cholest-4-ene-3,6-dione, (4) cholest-5-ene-3β-ol, (5) 5α-cholestane-3,6-dione, (6) β-Sitosterol and (7) Saringosterol. The MTT method was used to test the cytotoxicity of the compounds against the human cancer cell lines, HCT-8, Bel-7402, BGC-823, A549 and HELA. Compounds 1, 2, 3 and 5 showed moderate cytotoxic activity against human cancer cell lines. 相似文献
7.
The effects of two intraperitoneal injections of human chorionic gonadotropin (HCG) or [D-ALA6, pro9-N-ethylamide]-luteinizing hormone releasing hormone analogue (LHRH-A), respectively, and the combined effect of LHRH-A with
pimozide (PIM), a dopamine antagonist, on ovulation in female mud skipper were investigated. A high rate of ovulation (83.3%)
was observed after injection with HCG(30 I. U./g). Injection of LHRH-A at a total dosage of 2 μg/g was 100% effective in inducing
ovulation. No ovulations occurred in the group receiving a low dosage of LHRH-A (0.02 μg/g). Injection of LHRH-A (0.2 μg/g)
with PIM (10 or 20 μg/g) induced greater ovulatory response than injection with LHRH-A (0.2 μg/g) alone. PIM at total dosages
of 0.2 μg/g or 2 μg/g did not enhance the potency of LHRH-A to stimulate ovulation. 相似文献
8.
Hong Wanshu 《中国海洋湖沼学报》1992,10(1):40-43
The plasma cortisol and glucose concentrations were determined in mature female striped mullet (Mugil cephalus L.) subjected to short term intense handling stress. The results indicated that plasma cortisol levels reached a peak 20
min after stress and declined gradually afterwards. The highest concentration of plasma glucose was observed 30 min after
stress. The present study showed that the rise of plasma glucose was associated with the plasma cortisol levels. 相似文献
9.
洪万树 《中国海洋湖沼学报》1992,(1)
The plasma cortisol and glucose concentrations were determined in mature female striped mullet (Mugil cephalus L . ) subjected to short term intense handling stress . The results indicated that plasma cortisol levels reached a peak 20 min after stress and declined gradually afterwards . The highest concentration of plasma glucose was observed 30 min after stress . The present study showed that the rise of plasma glucose was associated with the plasma cortisol levels . 相似文献
10.
魏印心 《中国海洋湖沼学报》2002,20(2):142-148
The species composition, horizontal distribution and seasonal succession of the phyto-plankton at five sampling stations in the channel between Dongting Lake and the Changjiang River, China were studied from May 1995 to December 1997. A total of 416 taxa were observed; diatoms comprised the most diverse taxonomic group representing 58.2 % of the total species. The β-mezotrophic indicators were 92 taxa or 22 % of the total, the a-mezotrophic or α, β-eutrophic indicators decreased distinctly to 20 taxa or 4.8 % of the total. The species number and composition of various phyla were approximately similar at Stations 1, 2, 3 and 4, but at Station 5 the number of species was the minimum and the ratio of diatoms to total phytoplankton in the number of species was the highest. In seasonal succession of the phytoplank-ton species, the number was the highest in May and June, lower in December, January, March and July in the channel. The dominant species were different in different months. The ratio of diatoms species number to blue green algae and green algae species number diminished gradually from winter to summer and autumn, and then increased gradually from autumn to winter and early spring in the annual cycle. Margalef, Simpson and Shannon—Weaver diversity indices changed in different months, their values were higher in winter, lower in summer. Nygaard‘s diatoms quotients were lower in winter, then in spring and autumn, higher in summer. These results indicated that the water quality was the best in winter, better in spring and autumn than in summer. The relationship between the structure of the phytoplankton communi-ty and the water environmental quality was discussed. 相似文献
11.
Twenty-four compounds including eight steroids (1–8), nine triterpenoids (9–16, 24), three flavonoids (20–22), and four benzenecarboxylic derivatives (17–19, 23) were isolated and identified from stems and twigs of medicinal mangrove plant Sonneratia caseolaris. The structures of the isolated compounds were determined by extensive analysis of their spectroscopic data. Among these
metabolites, compounds 1, 4–20 and 22–24 were isolated and identified for the first time from S. caseolaris. In the in vitro cytotoxic assay against SMMC-7721 human hepatoma cells, compound 21 (3′,4′,5,7-tetrahydroxyflavone) exhibited significant activity with IC50 2.8 μg/mL, while oleanolic acid (14), 3,3′-di-O-methyl ether ellagic acid (18), and 3,3′,4-O-tri-O-methyl ether ellagic acid (19) showed weak activity. None of these compounds displayed significant antibacterial activites.
Supported by the National Natural Science Foundation of China (No. 30770234); Knowledge Innovation Program of Chinese Academy
of Sciences (KZCX2-YW-211-04); Department of Science and Technology of Shandong Province (No.2006GG2205023) 相似文献
12.
mODUCTIONTheislandsOfHaitan,Yuo,Dalian,DowiangandCaoguinPingtanCoUntyofFu-jianProvincearetogetherthewhtoasPingtan(25'l5'-25o45'E,l19"32'-12o"lo'N,EaStChinaSea).AmngthemHaitangIslanisthedrinoneinPingtanCotmty,andthelargestinFuianProvince.RngtanhaSanatuIalfishinggroUn(SeduMOUntaln)beingrenownedboghoutthecOUnnyandawelldeVfoPedaqUacultUreindusny.Pingtanwa-tersresotirceswerestirveyedforthefirsttimebytheauthorssothattheknowedgegainedcanbeaPPliedforbettereaploitahon,PIDechon,andde… 相似文献
13.
Seven compounds (1–7) were identified from the cultivation of the endophytic fungus Exophiala oligosperma (EN-21) that was isolated from the inner tissue of the marine red alga Laurencia similis. Their structures were identified with spectroscopic and chemical methods as 2-phenoxynaphthalene (1), (2S, 3R, 4E, 8E)-1-O-β-D-glucopyranosyl-3-hydroxy-2-[(R)-2′-hydroxyoctadecanoyl] amino-9-methyl-4, 8-octadeca-diene (2), (22E,24R)-ergosta-7,22-dien-3β,5α,6β-triol (3), (22E, 24R)-3β, 5α, 9α-trihydroxy- ergosta-7, ... 相似文献
14.
Serotonin (5-HT) has been found to stimulate meiotic maturation of oocytes in many molluscs. During maturation, several signaling pathways are involved, especially the phosphatidylinositol and cAMP pathways. In order to examine the possible role of the phosphatidylinositol signaling pathway in regulating oocyte maturation in Mercenaria mercenaria, the effects of the activator/inhibitor of phospholipase (PLC) and protein kinase C (PKC) on serotonin-induced maturation were studied. Results show that high-concentrations of neomycin (inhibitor of PLC) blocked oocyte maturation, while 9, 10-dimethyl-1, 2-benzanthracene (DMBA, activator of PLC) promoted oocyte maturation in the presence of serotonin. It was also found that in the presence of serotonin, phorbol 12-myristate 13-acetate (PMA, activator of PKC) inhibited oocyte maturation, while sphingosine (inhibitor of PKC) stimulated oocyte maturation. These results indicate that serotonin-induced oocyte maturation requires the activation of the phosphatidylinositol pathway. Decrease of PLC inhibited serotonin-induced oocyte maturation, whereas a decrease of PKC stimulated the maturation. Thus, our study indicates that serotonin promotes maturation of M. mercenaria oocytes through PLC stimulated increase in calcium ion concentration via inositol-1, 4, 5-trisphosphate (IP3) but not PKC. 相似文献
15.
The unicellular cyanobacterium Synechocystis sp. PCC 6803, a model organism known for its unique combination of highly desirable molecular genetic, physiological and
morphological characteristics, was employed in the present study. The species was cultured in BG11 liquid medium contained
various initial concentrations of Pb2+ and Cd2+ (0, 0.5, 1, 2, 4, 6 and 8 mg/L). The experiment was conducted for six days and the metal induced alterations in the ultrastructure,
growth and pigment contents were assessed. Alterations in the ultrastructure of the Synechocystis sp. PCC 6803 cells became evident with the increased (>4 mg/L Pb2+) metal concentration. The photosynthetic apparatus (thylakoid membranes) were found to be the worst affected. Deteriorated
or completely destroyed thylakoid membranes have made large empty spaces in the cell interior. In addition, at the highest
concentration (8 mg/L Pb2+), the polyphosphate granules became more prominent both in size and number. Despite the initial slight stimulations (0.2,
3.8 and 6.5% respectively at 0.5, 1 and 2 mg/L Pb2+), both metals inhibited the growth in a dose-dependent manner as incubation progressed. Pigment contents (chlorophyll α, β carotene and phycocyanin) were also decreased with increasing metal concentration. Cells exposed to 6 mg/L Pb2+, resulted in 36.56, 37.39 and 29.34% reductions of chlorophyll α, β carotene and phycocyanin respectively over the control. Corresponding reductions for the same Cd2+concentrations were 57.83, 48.94 and 56.90%. Lethal concentration (96 h LC50) values (3.47 mg/L Cd2+ and 12.11 mg/L Pb2+) indicated that Synechocystis sp. PCC 6803 is more vulnerable to Cd2+ than Pb2+.
Supported by the Chinese Scholarship Council 相似文献
16.
A laboratory experiment was conducted to assess the bioaccumulation of Pb2+ and its effects on growth, morphology and pigment contents of Spirulina (Arthrospira) platensis. The specimen cultured in Zarrouk liquid medium was treated with various initial metal concentrations (0, 5, 10, 30, 50 and
100 μg mL−1). The growth of S. platensis was adversely affected by Pb2+ at high concentrations (30, 50 and 100 μg mL−1). However, at low concentrations (5 μg mL−1), Pb2+ could stimulate its growth slightly. The pigment contents (chlorophyll α and β carotene) were decreased in a dose-dependent
manner. The highest reductions (67% and 53% respectively in chlorophyll α and β carotene) were observed in 100 μg mL−1 treatment group. The LC50 (96 h) of Pb2+ was measured as 75.34 μg mL−1. Apart from a few cases of filament breakages at elevated concentrations (50 and 100 μg mL−1), morphological abnormalities are not specific. Metal bioaccumulation increased with Pb2+ concentrations, but decreased with exposure time. The maximum accumulated amount was 188 mg g−1 dry weight. The bioconcentration factor (BCF) reached to a peak at day 2, followed by a gradual reduction for all the exposure
concentrations. S. platensis is able to tolerate considerably high Pb2+ concentrations. Consequently it can be used as a potential species to remove heavy metal from contaminated waters. 相似文献
17.
18.
The structural feature of agar polysaccharides fromPorphyra haitanensis grown in south China and transplanted to the north was investigated by fractionation on DEAE—Sephadex A 50, chemical analysis,
and infrared and13C-NMR spectroscopy. The agars composed mainly of charged molecules were eluted from DEAE—Sephadex A 50 with 1.0 mol/L NaCl
solution from the southernP. haitanensis and with 0.5 mol/L NaCl from the northern one. The13C-NMR spectra showed that agarobiose [(1→3)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-α-L-galactopyranose] and the biological precursor of agarobiose [(1→3)-β-D-galactopyra nosyl-(1→4)-6-sulfate-α-L-galactopyranose] were the major disaccharide repeating units in the charged fractions. The content of the biological precursor
in the agar polysaccharides from southernP. haitanensis was higher than that in the northern one, the content of the biological precursor extracted from cold water was higher than
that from hot water, and the content of 6-OMe-D-galactose in the southernP. haitanensis polysaccharides was higher than in the northern one. This distinct difference will be of significance for further study of
the physiological characters ofP. haitanensis.
Contribution No. 1849 from the Institute of Oceanology, Academia Sinica. 相似文献
19.
Giant red sea cucumber (Parastichopus californicus) is an under-utilized species due to its high tendency to autolysis.The aim of this study was to evaluate the functional properties of collagen hydrolysates from this species.The degree of hydrolysis (DH),amino acid composition,SDS-PAGE,emulsion activity index (EAI),emulsion stability index (ESI),foam expansion (FE),and foam stability (FS) of hydrolysates were investigated.The effects of pH on the EAI,ESI FE and FS of hydrolysates were also inves-tigated.The results indicated that the β and α1 chains of the collagen were effectively hydrolyzed by trypsin at 50℃ with an En-zyme/Substrate (E/S) ration of 1:20 (w:w).The DH of collagen was up to 17.3% after 3 h hydrolysis with trypsin.The hydrolysates had a molecular weight distribution of 1.1 17 kDa,and were abundant in glycine (Gly),proline (Pro),glutamic acid (Glu),alanine (Ala) and hydroxyproline (Hyp) residues.The hydrolysates were fractionated into three fractions (< 3 kDa,3 10 kDa,and > 10 kDa),and the fraction of 3 10 kDa exhibited a higher EAI value than the fraction of > 10 kDa (P<0.05).The fraction of > 10 kDa had higher FE and FS values than other fractions (P<0.05).The pH had an important effect on the EAI,ESI,FE and FS.All the fractions showed undesirable emulsion and forming properties at pH 4.0.Under pH 7.0 and pH 10.0,the 3 10 kDa fraction showed higher EAI value and the fraction of > 10 kDa showed higher FE value,respectively.They are hoped to be utilized as functional ingredients in food and nutraceutical industries. 相似文献
20.
Extraction of organochlorine pesticides in sediments using soxhlet,ultrasonic and accelerated solvent extraction techniques 总被引：2，自引：0，他引：2
LANG Yinhai CAO Zhengmei and NIE Xinhua College of Environmental Science Engineering Ocean University of China Oingdao P.R.China Bureau of Environmental Protection of Qingdao Qingdao P. R. China 《中国海洋大学学报(英文版)》2005,4(2):173-176
The application of soxhlet, ultrasonic and accelerated solvent extraction techniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT, p,p'-DDT and p, p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits of quantification ranged from 0.002μgg-1 to 0.004μgg-1, and the recoveries of organochlorine pesticides with the three extraction techniques were acceptable (>80.7%). With a mass selective detector, better results were obtained by accelerated solvent extraction using hexane-acetone (1:1) as compared with soxhlet and ultrasonic extraction. It was shown that the accelerated solvent extraction was the optimum technique for the analysis of organochlorine pesticides in sediments. The general features of the three extraction techniques are also presented. 相似文献