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51.
V. A. Brykov O. Ya. Semenikhina N. K. Kolotukhina 《Russian Journal of Marine Biology》2000,26(4):258-263
This paper presents the results of the analysis of density dynamics of the larvae of the Pacific mussel in plankton, and experimental
data on their settling on collectors in Vostok Bay, Sea of Japan, obtained in May–September 1989. It was found that, in the
summer-autumn season, complex demographic processes occur on the suspended anthropogenic substrata. These processes are caused
by the primary settling of pelagic larvae and by the secondary settling of juvenile mussels. 相似文献
52.
D. Medaković 《Helgoland Marine Research》2000,54(1):1-6
To decide whether a physiological role can be attributed to enzymatic activity with respect to crystal formation and biomineralization
of the first larval shell, carbonic anhydrase (CA) activity was measured in embryos and larvae of the blue mussels Mytilus edulis L. Also, CA activity was determined in the mantle edge and gonads of adult mussels with different shell length and condition
index. The intention was to find a possible correlation between CA activity and adult shell calcification, i.e. gonadal maturation.
The comparison of CA activity in different developmental stages of mussels and the results of an X-ray diffraction study of
biomineralization processes in embryonic and larval shells indicate that CA activity is maximal at the end of several developmental
stages. Consequently, the increase in CA activity precedes some physiological changes, i.e. the somatoblast 2d formation and
the occurrence of the first calcite and quartz crystals in embryos, shell field formation in the gastrula stage, shell gland
and periostracum production in trochophores, and rapid aragonite deposition in larval prodissoconch I and prodissoconch II
shells. Furthermore, it was found that in adult mussels CA activity was quite variable and that in the mantle edge it was
frequently inversely related to the activity in the gonad.
Received: 28 November 1998 / Received in revised form: 30 August 1999 / Accepted: 31 August 1999 相似文献
53.
54.
Luca Galluzzi Antonella Penna Elena Bertozzini Maria Grazia Giacobbe Magda Vila Esther Garcs Silvia Prioli Mauro Magnani 《Harmful algae》2005,4(6):337
Paralytic shellfish poisoning (PSP) is a syndrome caused by the consumption of shellfish contaminated with neurotoxins produced by organisms of the marine dinoflagellate genus Alexandrium. A. minutum is the most widespread species responsible for PSP in the Western Mediterranean basin. The standard monitoring of shellfish farms for the presence of harmful algae and related toxins usually requires the microscopic examination of phytoplankton populations, bioassays and toxin determination by HPLC. These procedures are time-consuming and require remarkable experience, thus limiting the number of specimens that can be analyzed by a single laboratory unit. Molecular biology techniques may be helpful in the detection of target microorganisms in field samples. In this study, we developed a qualitative PCR assay for the rapid detection of all potentially toxic species belonging to the Alexandrium genus and specifically A. minutum, in contaminated mussels. Alexandrium genus-specific primers were designed to target the 5.8S rDNA region, while an A. minutum species-specific primer was designed to bind in the ITS1 region. The assay was validated using several fixed seawater samples from the Mediterranean basin, which were analyzed using PCR along with standard microscopy procedures. The assay provided a rapid method for monitoring the presence of Alexandrium spp. in mussel tissues, as well as in seawater samples. The results showed that PCR is a valid, rapid alternative procedure for the detection of target phytoplankton species either in seawater or directly in mussels, where microalgae can accumulate. 相似文献
55.
《Bioscience, biotechnology, and biochemistry》2013,77(12):2699-2701
A highly potent attachment-inhibitor, polygodial, was isolated from a hexane extract of the leaves of Tasmannia lanceolata. The attachment-inhibiting activity of polygodial against the blue mussel was increased 4-fold when used in combination with sorbic acid, anethole, and indole. 相似文献
56.
Thomas J. Hilbish Brian L. Bayne Amanda Day 《Evolution; international journal of organic evolution》1994,48(2):267-286
Two divergent taxa in the marine mussel genus Mytilus are largely isolated geographically and are routinely exposed to distinctly different thermal environments. We tested the hypothesis that the two taxa are physiologically differentiated with respect to temperature and examined the evolved adaptations allowing one of the taxa to exploit habitats where warm-temperate conditions prevail for prolonged periods. We first analyzed the physiological response to high temperature of mussels collected from a hybrid population containing members of both pure taxa, F, hybrids, and a variety of introgressed genotypes. The experimental temperature of 23°C was chosen to be permissive to the taxon that occurs in warm-temperate regions (Mytilus galloprovincialis) and restrictive to the cold-water taxon (Mytilus edulis). The results show that the two taxa are physiologically differentiated. Under the experimental conditions, M. galloprovincialis exhibited a threefold higher feeding rate and a slightly elevated metabolic rate compared with M. edulis. These differences did not result in a significant difference in net energy balance between the two taxa, probably because of an interaction between physiological response and food availability. However, M. galloprovincialis grew significantly faster in the field, indicating that the physiological differences observed in the laboratory also occur in nature. Numerous introgressed genotypes provided the opportunity to test for cosegregation between the physiological differences and four highly differentiated genetic markers. Two of the markers (esterase and octopine dehydrogenase) cosegregate with variation in feeding rate and shell growth and explained most of the physiological differences observed between taxa. A strong concordance existed between these two loci, suggesting that they may be linked and may mark segregation of the same linkage group. The results suggest that the physiological differentiation between these taxa may be controlled by a few genes (perhaps only one) each with large effect. 相似文献
57.
The characteristics of algal-induced spawning of the marine mussel Mytilus californianus were studied. Exposure of mature individuals to culture suspensions of the unicellular alga Pseudoisochrysis paradoxa elicited copious and synchronous release of gametes. Alkaline conditions were necessary to make the animals responsive to the spawning stimulus provided by the algae. The filtered, cell-free fraction of the algal suspensions also stimulated spawning, suggesting that an active principle is secreted into the culture media by the algae. A key requirement for the development of an efficient and economically viable molluscan mariculture program is the capability to induce copious, synchronous spawning of gravid individuals. This procedure should be easily managed and have no deleterious effects on the gametes, fertilization, or the ontological development of the animals. Miyazaki [1] induced spawning in male oysters by exposing them to an extract of green algae. Recently it was reported that the marine mussels, M. californianus, could be induced to spawn by exposing them to cultures of the marine algae, P. paradoxa [2], This paper summarizes our efforts to characterize this spawning response of mussels to high concentrations of cultured marine algae. 相似文献
58.
Summary The main iron-binding protein in the hepatopancreas of the musselMytilus edulis, which had been previously iron-loaded by exposure to carbonyl iron (spheres of elemental iron less than 5 m diameter), has been isolated to electrophoretic purity and identified as ferritin. This ferritin hasM
r, of 480000, pI of 4.7–5.0 and is composed of two subunits,M
r 18500 andM
r 24600. Under the electron microscope, it appears as electron-dense iron cores of average diameter 5 nm surrounded by a polypeptide shell to a final average overall diameter of 11 nm. The purified protein contains, on average, 200 iron atoms/molecule protein. On immunodiffusion,M. edulis hepatopancreas ferritin gives a partial cross-reaction with antiserum to horse spleen ferritin and lamprey (Geotria australis) liver ferritin but does not react with antiserum to chiton (Acanthopleura hirtosa) haemolymph ferritin. 相似文献
59.
Background: Histopathological assessments approaches in bivalves have become an important tool in environmental toxicology. This study seeks to develop a quantitative histopathological index (Ih) and inflammation score as biomarkers in the aim to assess the health status of nanoparticles exposed mussels.Methods: Digestive gland hematoxylin and eosin (H&;E) stained sections from Mytilus galloprovincialis were assessed after in vivo exposure (for 3, 6 and 12?h) to silver nanoparticles (Ag-NPs?50?nm and Ag-NPs?100?nm) prior and after manipulating the potential uptake pathways (clathrin- and caveolae-mediated endocytosis) using amantadine and nystatin as blockers. Quantitative models evaluate the impacts of nanoparticles size, as well as their uptake routes within different time of exposure on the inflammation intensity, the digestive tubules histomorphometry and the histopathological indices.Results: Silver nanoparticles clearly induced histopathological alterations in digestive gland (maximum inflammation 2.75 with AgNP?100?nm [p?0.05]; significant Ih with AgNP?50?nm and AgNP?100?nm at different time-points [p?0.05]). Significant Ih were recorded after uptake routes were blockade: AgNP?50?nm?+?nystatin and AgNP?100?nm?+?amantadine; [p?0.05] all time-points.Conclusions: Histopathological assessments showed to be promising tool in nanotoxicity which seems to depend on nanoparticles size, exposure time and interestingly to uptake routes. It was not clear: is it the length of exposure or the size of particles is more impactful. 相似文献
60.
Marine mussels (Mytilus trossulus) attach to a wide variety of surfaces underwater using a protein adhesive that is cured by the surrounding seawater environment. In this study, the influence of environmental post-processing on adhesion strength was investigated by aging adhesive plaques in a range of seawater pH conditions. Plaques took 8–12 days to achieve full strength at pH 8, nearly doubling in adhesion strength (+94%) and increasing the work required to dislodge (+59%). Holding plaques in low pH conditions prevented strengthening, causing the material to tear more frequently under tension. The timescale of strengthening is consistent with the conversion of DOPA to DOPA-quinone, a pH dependent process that promotes cross-linking between adhesive proteins. The precise arrangement of DOPA containing proteins away from the adhesive-substratum interface emphasizes the role that structural organization can have on function, an insight that could lead to the design of better synthetic adhesives and metal-coordinating hydrogels. 相似文献