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1.
《中国海洋大学学报(英文版)》2016,(5)
The morphology and phylogeny of two hypotrichous ciliates, Metaurostylopsis parastruederkypkeae n. sp. and Neourostylopsis flavicana(Wang et al., 2011) Chen et al., 2013 were investigated based on morphology, infraciliature and the small subunit(SSU) ribosomal RNA gene(r RNA) sequence. The new species, M. parastruederkypkeae n. sp. was identified according to its characteristics: body shape ellipsoidal, size about(165–200) ×(45–60) μm in vivo, cell color reddish; two types of cortical granules including wheat grain-like and yellow-greenish larger ones along the marginal cirri rows and dorsal kineties and dot-like and reddish smaller ones, grouped around marginal cirri on ventral side and arranged in short lines on dorsal side; 26–41 adoral membranelles; three frontal and one parabuccal, five to seven frontoterminal, one buccal, and three to six transverse cirri; seven to thirteen midventral pairs; five to nine unpaired ventral cirri, five to seven left and three to five right marginal rows; and three complete dorsal kineties. Phylogenetic analysis based on SSU r DNA sequences showed that both Metaurostylopsis and Neourostylopsis are monophyletic. As the internal relationship between and within both genera are not clear, further studies on the species in these two genera are necessary. The key characteristics of all known twelve Metaurostylopsis-Apourostylopsis-Neourostylopsis species complex were updated. 相似文献
2.
The living morphology and infraciliature of two rare marine ciliates, Placus salinus Dietz, 1964 and Strombidium apolatum Wilbert and Song, 2005, collected from the coastal waters near Qingdao, China, were investigated by in vivo observation and protargol impregnation technique. The improved diagnosis for Placus salinus is as follows: medium-sized marine Placus, in vivo (50–60)μm×(30–40)μm; cell elliptical to barrel-shaped; 28–31 somatic kineties; single macronucleus usually ellipsoid and
one micronucleus located in the indention of the macronucleus; one contractile vacuole posteriorly positioned. Strombidium apolatum is characterized by: marine strombidium (40–60)μm×(30–45)μmm in vivo, cordiform in shape with somewhat pointed posterior end and conspicuous apical protrusion; extrusomes prominent, about 15μm
in length and evenly arranged along the circle kinety; about 16 collar and 5–6 buccal membranelles; one elongate macronucleus
and one micronucleus; circle and ventral kineties consisting of about 53 and 45 dikinetids respectively. 相似文献
3.
From June 2003 to June 2004, an investigation on the life cycle, production and trophic basis of dominant species of macrozoobenthos community in a second-order river of the Hanjiang River basin, Hubei, China was carded out. The results showed that the dominant species Leptophlebia sp. and Ephemera sp. appeared to develop two generations per year, and there was a small overlap in the two generations of both species. The pupation of Leptophlebia sp. mainly occurred in autumn and winter, while pupation of Ephemera sp. mainly took place in summer and winter. The standing stocks of the Leptophlebia sp. population and Ephemera sp. population had two peaks in a year. The cohort production and cohort P/B ratio of the Leptophlebia sp. population estimated by size frequency method were 19.018 1 g/m^2.a and 5.7 respectively, while its annual production and P/B ratio were 38.036 2 g/m^2.a and 11.4. The cohort production and cohort P/B ratio of the Ephemera sp. population were 38.015 9 g/m^2.a and 5.9, while its annual production and P/B ratio were 76.031 8 g/m^2.a and 11.8. 相似文献
4.
To investigate the antitumor effect of bromophenol derivatives in vitro and Leathesia nana extract in vivo, six bromophenol derivatives 6-(2,3-dibromo-4,5-dihydroxybenzyl)-2,3-dibromo-4,5-dihydroxy benzyl methyl ether (1), (+)-3-(2,3-dibromo-4,5-dihydroxyphenyl)-4-bromo-5,6-dihydroxy-1,3-dihydroisobenzofuran (2), 3-bromo-4-(2,3-dibromo-4,5-dihydroxybenzyl)-5-methoxymethyl-pyrocatechol (3), 2,2′,3,3′-tetrabromo-4,4′,5,5′-tetrahydroxy-diphenylmethane (4), bis(2,3-dibromo-4,5-dihydroxybenzyl) ether (5), 2,2′,3-tribromo-3′,4,4′,5-tetrahydroxy-6′-ethyloxymethyldiphenylmethane (6) were isolated from brown alga Leathesia nana, and their cytotoxicity were tested by MTT assays in human cancer cell lines A549, BGC-823, MCF-7, B16-BL6, HT-1080, A2780,
Bel7402 and HCT-8. Their inhibitory activity against protein tyrosine kinase (PTK) with over-expression of c-kit was analyzed also by ELISA. The antitumor activity of ethanolic extraction of Leathesia nana (EELN) was evaluated on S180-bearing mice. All compounds showed very potent cytotoxicity against all of the eight cancer cell lines with IC50 below 10 μg/mL. In PTK inhibition study, all bromophenol derivatives showed moderate inhibitory activity and compounds 2,
5 and 6 showed significant bioactivity with the inhibition ratio of 77.5%, 80.1% and 71.4%, respectively. Pharmacological
studies reveal that EELN could inhibit the growth of Sarcoma 180 tumor and increase the indices of thymus and spleen to improve
the immune system remarkably in vivo. Results indicated that the bromophenol derivatives and EELN can be used as potent antitumor agents for PTK over-expression
of c-kit and considered in a new therapeutic strategy for treatment of cancer.
Supported by the National High Technology Research and Development Program of China (863 Program, No. 2007AA09Z410) and Knowledge
Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-209) 相似文献
5.
For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was
injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension of Vibrio alginolyticus in density of 2×107 CFU/ml, while each individual in the control group was injected i.p. with 0.2 ml sterile saline solution (0.85%). It was
observed that the artificial injection of V. alginolyticus significantly increased the number of erythrocytes, leucocytes, lymphocytes in peripheral blood as well as peripheral serum
antibacterial activity and antibody titer of large yellow croaker, and significantly reduced the number of peripheral blood
granulocytes as compared with those in the control group. No significant difference in acid phosphytase and superoxide dismutase
activity of serum was detected between the two groups. It is suggested that non-specific immune factors including leucocytes
and anti-bacteria substance in peripheral blood played important role at the initial stage of infection, and specific immune
factors such as antibody then played important role in response to anti-infection at the latter stage.
Supported by the National High Technology Research and Development Program of China (863 program, No. 2007AA09Z115) and Technology
Program of Xiamen (No. 3502Z73019) 相似文献
6.
The scyphozoan Aurelia aurita (Linnaeus) sp. l., is a cosmopolitan species-complex which blooms seasonally in a variety of coastal and shelf sea environments around the world. The effects of different microalgal species on the growth of newly-released Aurelia sp.1 ephyrae were studied under laboratory conditions. We fed ephyrae with four different microalgal species (diatom, autotrophic dinoflagellate, heterotrophic dinoflagellate, and chlorophyta) plus Artemia nauplii for 12-24 d at 18°C. Results showed that the growth rate diverged significantly for Artemia nauplii compared to other food types. In addition, there was no significant variation between the growth rates for Skeletonema costatum and Prorocentrum donghaiense, and no significant variation was found in the growth rates for N. scintillans and P. subcordiformis. Artemia nauplii could support the energy requirement for the newly-released ephyrae to develop to meduase, and the ephyrae with Artemia nauplii showed a significant average growth rate of 25.85% d?1. Newly-released ephyrae could grow slightly with some species of microalgae in the earliest development stage. Chain diatom Skeletonema costatum and autotrophic dinoflagellate Prorocentrum donghaiense, could not support the growth of the ephyrae, while heterotrophic dinoflagellate Noctiluca scintillans and chlorophyta Platymonas subcordiformis could support the growth of the ephyrae. However, none of the ephyrae fed with the tested phytoplankton could mature to medusae. 相似文献
7.
Two new species of the genusTinocladia Kylin (1940)T. eudesmoides Ding et Lu sp. nov. andTinocladia zhangii Ding et Lu sp. nov., are described.T. eudesmoides is mainly characterized by its longitudinally and transversely produced sub-cortical filaments from the medulla, its short
uniseriate assimilating filaments, usually composed of 6–10 cells with slightly swollen and narrow ultimate cells, and its
unilocular sporangia (60–115)×55–70μm, variable in size.T. zhangii is mainly characterized by its very solid frond, not rip apart by hands, its evident longer primary branches, its short and
slender secondary branches, with very evident sub-cortical layer, and filaments divided repeatedly, and its large and small
unilocular sporangia, with the latter borne on an evidently swollen pedicel.
Project B80981816 supported by the NSFC.
Contribution No. 4443 from the Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China. 相似文献
8.
Synedra ulna var, repanda Q. X. Wang & Q. M. You, a new variety of Synedra (Bacillariophyta) from Xinjiang, China, is described and illustrated, and the characteristic of the variety: includes undulate-linear valves and straight pseudoraphe, differs from other species of Synedra. 相似文献
9.
The information of trophic relationship is important for studying the Southern Ocean ecosystems. In this study, three dominant krill species, Euphausia superba, Thysanoessa macrura and Euphausia crystallorophias, were collected from Prydz Bay, Antarctica, during austral summer of 2009/2010. The composition of fatty acids in these species was studied. E. superba and T. macrura showed a similar fatty acid composition which was dominated by C14:0, C16:0, EPA (eicosapentenoic acid) and DHA (decosahexenoic acid) while E. crystallorophias showed higher contents of C18:1(n-9), C18:1(n-7), DHA and EPA than the former two. Higher fatty acid ratios of C18:1(n-9)/18:1(n-7), PUFA (polyunsaturated fatty acid)/SFA (saturated fatty acid), and 18PUFA/16PUFA indicated that E. crystallorophias should be classified as a typical omnivore with a higher trophic position compared with E. superba and T. macrura. 相似文献
10.
Reactive oxygen species (ROS) scavengers, including ascorbate peroxidase, superoxide dismutase, catalase and peroxidase, are the most commonly used biomarkers in assessing an organisms’ response to many biotic and abiotic stresses. In this study, we cloned an 866 bp GST (phi) gene in Lemna minor and investigated its characteristics, expression and enzymatic activities under 75 μmol/L cadmium concentrations in comparison with other ROS scavengers. GST (phi) gene expression patterns were similar to those of other scavengers of ROS. This suggests that GST (phi) might be involved in responding to heavy metal (cadmium) stress and that its expression level could be used as a bio-indicator in monitoring cadmium pollution. 相似文献
11.
Jia Jia Junhong Bai Wei Wang Guangliang Zhang Xin Wang Qingqing Zhao Shuai Zhang 《中国地理科学(英文版)》2018,28(3):411-419
Little information is available on biogenic elements (carbon, nitrogen, phosphorus and sulfur) and the ecological stoichiometric characteristics of plants in coastal wetlands. To investigate the contents of carbon, nitrogen, phosphorus and sulfur of plants, and their ecological stoichiometric characteristics in the Yellow (Huanghe) River Delta, plant samples were collected from two typical salt marshes (Suaeda salsa and Phragmites australis wetlands) during the period of from August to October in 2007, and the ratios of C/N, C/P, N/P, C/N/P and C/N/P/S were calculated. Results showed that during the studying period, plant C, N and P were lower than the global average values, and plant N and P were lower than the China’s average values. Leaf C and S in Suaeda salsa were significantly lower than those in Phragmites australis (P < 0.05), and leaf N and P in Suaeda salsa and Phragmites australis showed no significant differences (P > 0.05). Average C/N ratios were 23.75 in leaf, 73.36 in stem, 65.67 in root of Suaeda salsa, and 33.77 in leaf, 121.68 in stem, 97.13 in root of Phragmites australis. Average C/N ratios of Suaeda salsa and Phragmites australis were all great than 25, indicating the salt marsh in the Yellow River Delta is an N limitation system. Average C/P ratios were 276.78 in leaf, 709.28 in stem and 1031.32 in root of Suaeda salsa, and 536.94 in leaf, 768.13 in stem and 875.22 in root of Phragmites australis. The average N/P ratios of Suaeda salsa were 12.92 in leaf, 10.77 in stem and 10.91 in root, and the average N/P ratios of Phragmites australis were 16.40 in leaf, 7.40 in stem and 6.92 in root, indicating the Suaeda salsa wetlands were N limited and Phragmites australis wetlands were N limited in August and P limited in October in 2007. The average C/N, C/P and C/N/P ratios in Suaeda salsa and Pragmites australis were higher than the global average values, indicating the lower quality of organic matter provided by wetland plants in the Yellow River delta. 相似文献
12.
Compounds isolated and identified in a culture of the alga-endophytic fungus Talaromyces sp. cf-16 included two naturally occurring alkaloids, 2-[(S)-hydroxy(phenyl)methyl]-3-methylquinazolin-4(3H)-one (1a) and 2-[(R)-hydroxy(phenyl)methyl]-3-methylquinazolin-4(3H)-one (1b), that were identified for the first time. In addition, seven known compounds (2–8) were obtained from the culture. Following chiral column chromatography, compounds 1a and 1b were identified as enantiomers by spectroscopic analyses and quantum chemical calculations. Bioassay results showed that 5 was more toxic to brine shrimp than the other compounds, and that 3–6 could inhibit Staphylococcus aureus. 相似文献
13.
Status of two <Emphasis Type="Italic">Coreius</Emphasis> species in the Three Gorges Reservoir,China
Dam construction alters natural flow regimes which, in turn, cause significant changes in fish communities during and after impoundment. The construction of the Three Gorges Reservoir, from impoundment of the Changjiang (Yangtze) River, China, may have affected native fish species. Thus, the status of two lotic freshwater fish species, Coreius heterodon and C. guichenoti, were monitored in the Three Gorges Reservoir, including fish abundance, individual composition, growth, condition, and mortality. Data on both species were gathered from upstream, midstream and downstream areas of the reservoir and, where available, from studies published before and after dam construction. Lower abundance, slower growth, a less diversified age structure, poorer fish condition (indicated by hepatosomatic index) and higher mortalities were recorded in sites nearest the dam compared with upstream areas. Furthermore, after final impoundment, individual Coreius species inhabiting the area changed, with young individuals becoming more abundant, while upstream of the reservoir the two Coreius species became smaller at a given age. The results show that the status of the two Coreius species was subject to dramatic changes after impoundment. 相似文献
14.
Over the past few years, harmful algal blooms (HABs), such as red tides, have been frequently observed in coastal zones worldwide. The natural allelopathic interactions among macroalgae and red tide microalgae can alter the structure and succession of aquatic ecosystems. We investigated the influence of four environmental factors (temperature, salinity, light, and pH) on the allelopathic effects of the macroalgae Corallina pilulifera on red-tide forming Heterosigma akashiwo under laboratory conditions. Each of the factors had four levels: temperature (15, 20, 25, and 30°C), salinity (10, 20, 30, and 40), light (20, 100, 200 and 400 μmol/(m2?s)), and pH (5.5, 7, 8.5, and 10. Two-factor experiments were designed for each two environmental factors, with six combination treatments (temperature-salinity, temperature-light, temperature-pH, salinity-light, salinity-pH, and light-pH). Results showed that the allelopathic effect was significantly influenced by temperature, salinity, light, and pH. As single factors, the low temperature (15°C), low salinity (10), high-intensity light (400 μmol/(m2?s)), and high pH (10) treatments substantially enhanced the allelopathic effect. The strongest allelopathic effect of C. pilulifera on H. akashiwo was observed under the following treatments: 15°C and salinity of 40, 25°C and pH 10, 25°C with medium- to high-intensity light at 200–400 μmol/(m 2 ?s), 400 μmol/(m2?s) and salinity of 10, 400 μmol/(m2?s) and pH 10, and pH 10 with a salinity of 40. 相似文献
15.
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.
Diatoms are the only ecological phytoplankton that require silicic acid for growth. They are also the dominant contributor of ocean’s total primary productivity. Generation and circulation with silica walls, which the siliceous organisms form, is an important component of the marine biological pump. It is crucial to the study of the operational mechanisms of biological pump with different sea areas. Moreover, it is the key link to the study of global silicon cycle. This paper introduces the basic mechanism of the formation of diatom silica walls and a new way of researching silicic acid metabolism, namely the 2-(4-pyridyl)-5-((4-(2-dimethylaminoethylaminocarbamoyl)- methoxy)phenyl)oxazole (PDMPO) dyeing method. Under a fluorescence microscope after excitation with bright green fluorescence, it can combine with silicic acid to form a complex into the Si deposition within diatom cells. The advantage of this method is that it can monitor the metabolism of silicate after adding PDMPO. For experimentation and sample collection in each of the specified time points, samples were determinated through the unutilized silicic acid, silica dissoluble intracellular and Si deposition within diatom cells, not only using hot alkaline digestions method but also PDMPO dyeing method. Results showed a good linear relationship between PDMPO fluorescent value and biogenic silica concentration. It was also indicated that PDMPO had no deleterious impact on Skeletonema cf. costatum growth for 34 h and was useful for tracking newly-deposited biogenic silica in diatoms’ frustules. 相似文献
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Abies georgei var. smithii is an important plant species in Southeast Tibet, China. It has high ecological value in terms of biodiversity protection, as well as soil and water conservation. We analyzed the spatial pattern and associations of A. georgei var. smithii populations at different growth stages by using Ripley’s L function for point pattern analysis. The diameter structure was a nearly reverse ‘J’ shape. The amount of saplings and medium-sized trees accounts for a large part of the entire population, suggesting a high regeneration rate and an expanding population. In the transition from saplings to medium trees or to large trees, saplings show a significant aggregation distribution at small scales, while medium trees and large trees show a random distribution. There are significant inverse associations between saplings and medium trees and large trees at small scales, while there are no obvious associations between medium trees and large trees. The natural regeneration was affected by interspecific competition, and it was also affected by intraspecific competition. The joint effects of biological characteristics and environmental factors contribute to the spatial distribution pattern and associations of this A. georgei var. smithii population. 相似文献
20.
Micro-communities are supposed to have more potential functions of biodegradation of polysaccharides than single strain; however, the intestinal micro-communities involved in the biodegradation of Enteromorpha polysaccharides (EP) were seldom reported. In order to obtain the EP-degrading micro-community, the intestines of Siganus oramin was obtained to isolate the micro-communities, which were enriched by 0.3% of EP as the sole carbon source. A stable micro-community with EP degradative capability was achieved after seven generations of subculture, named H1. Results showed that H1 was able to degrade 75% of EP within 24 hours, and the activity of EP lyases reached 500 U mL?1 in 32 hours. With denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone library analysis, ten bacteria closely related to Marinomonas pontica, Microbacterium sp., Leucobacter chironomi, Cyclobacterium sp., Algoriphagus winogradskyi, Pseudoalteromonas sp. and Vibrio sp. were determined. Furthermore, compared with the DGGE bands sequence and the clone library analysis, the dominant bacteria of the EP-biodegrading micro- community were Pseudoalteromonas sp. and Vibrio sp., with the respective proportion of 38% and 46%, and they should play an important role in EP degradation together with other degrading bacteria in the micro-community H1. 相似文献