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121.
Yamile Gonzlez Aparecida S. Tanaka Izaura Y. Hirata Maday Alonso del Rivero Maria L.V. Oliva Mariana S. Araujo Maria A. Chvez 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,146(4):506
Human neutrophil elastase inhibition was detected in a crude extract of the marine snail Cenchritis muricatus (Gastropoda, Mollusca). This inhibitory activity remained after heating this extract at 60 °C for 30 min. From this extract, three human neutrophil elastase inhibitors (designated CmPI–I, CmPI–II and CmPI–III) were purified by affinity and reversed-phase chromatographies. Homogeneity of CmPI–I and CmPI–II was confirmed, while CmPI–III showed a single peak in reversed-phase chromatography, but heterogeneity in SDS-PAGE with preliminary molecular masses in the range of 18.4 to 22.0 kDa. In contrast, MALDI-TOF mass spectrometry of CmPI–I and CmPI–II showed that these inhibitors are molecules of low molecular mass, 5576 and 5469 Da, respectively. N-terminal amino acid sequences of CmPI–I (6 amino acids) and CmPI–II (20 amino acids) were determined. Homology to Kazal-type protease inhibitors was preliminarily detected for CmPI–II. Both inhibitors, CmPI–I and CmPI–II are able to inhibit human neutrophil elastase strongly, with equilibrium dissociation constant (Ki) values of 54.2 and 1.6 nM, respectively. In addition, trypsin and pancreatic elastase were also inhibited, but not plasma kallikrein or thrombin. CmPI–I and CmPI–II are the first human neutrophil elastase inhibitors described in a mollusk. 相似文献
122.
Inulinase production by a marine yeast <Emphasis Type="Italic">Pichia guilliermondii</Emphasis> and inulin hydrolysis by the crude inulinase 总被引:1,自引:0,他引:1
Marine yeast strain 1, isolated from the surface of a marine alga, was found to secrete a large amount of inulinase into the
medium. This marine yeast was identified as a strain of Pichia guilliermondii according to the results of routine yeast identification and molecular methods. The crude inulinase produced by this marine
yeast worked optimally at pH 6.0 and 60°C. The optimal medium for inulinase production was seawater containing 4.0% (w/v)
inulin and 0.5% (w/v) yeast extract, while the optimal cultivation conditions for inulinase production were pH 8.0, 28°C and
170 rpm. Under the optimal conditions, over 60 U ml−1 of inulinase activity was produced within 48 h of fermentation in shake flasks. A large amount of monosaccharides and a trace
amount of oligosaccharides were detected after the hydrolysis, indicating that the crude inulinase had a high exoinulinase
activity. 相似文献
123.
The accumulation of storage lipids during the biodegradation of 2,6,10,14-tetramethylhexadecane (phytane) by Mycobacterium ratisbonense strain SD4 grown under nitrogen-starved conditions was investigated. Detailed chemical analysis of intracellular metabolites revealed the existence of (at least) three different pathways for the catabolism of phytane, and the accumulation of significant proportions (39% of the total lipids) of several isoprenoid wax esters formed by condensation of oxidation products of the hydrocarbon. In contrast, triacylglycerols but no wax esters were accumulated by strain SD4 grown on hexadecane, the unbranched homologue of phytane. 相似文献
124.
Richard S. Nemeth Jeremiah Blondeau Steve Herzlieb Elizabeth Kadison 《Environmental Biology of Fishes》2007,78(4):365-381
This study compared the spatial and temporal patterns of red hind, Epinephelus guttatus, movement and migration from annual spawning aggregations on St Thomas (STT) and St Croix (STX), United States Virgin Islands.
Around STT E. guttatus migrated 6–33 km from a functional spawning migration area of 500 km2 and around STX E. guttatus migrated 5–18 km from an area of 90 km2. Similarities between sites were found in regards to timing of movement, temporal and spatial changes in sex ratios, annual
and lunar predictability and were synchronized with environmental cues. E. guttatus spawning aggregations in the Virgin Islands occur between the winter solstice (i.e., after December 20) and about February
20 of any year and show a distinctive peak 20–40 days after the winter solstice. Spawning typically occurred during periods
of declining seawater temperature and slacking currents within a temperature range of 26–27.5°C and current speed of 2.5–3.5 cm s−1. Males arrived early to spawning sites and stayed longer than females. These gender-based behavioral patterns are important
to E. guttatus reproductive dynamics and must be factored into future studies and the design of fisheries regulations to ensure sustainability
of spawning aggregation sites. The predictability of E. guttatus spawning aggregations relative to the winter solstice will be extremely beneficial for defining the temporal and spatial
aspects of area closures. The consistency and synchrony of movement and migration will improve both the efficiency of planning
research and monitoring programs and directing enforcement activities during critical time periods. Applying this knowledge
strategically will maximize the limited resources available for research and enforcement and lead to greater protection of
spawning aggregations. 相似文献
125.
The Mexican Government decreed Chinchorro Bank reef as a Biosphere Reserve in 1996. The aim of this study was to evaluate
the spatial and size-frequency distribution of Acropora spp. in order to provide further knowledge and tools to enhance management. A field survey was conducted, within six regions,
to locate and measure Acropora patches in the reef lagoon. Density, colony size and living tissue cover of Acropora colonies were evaluated using the line-intercept transect technique, combining direct observations and video transects. The
results showed that Acropora spp. was preferentially distributed in the southern regions; where cover and density were high. Based on these results and
considering that Acropora spp. produces landscape heterogeneity, which in turn generates shelter for other species, including some of considerable
economic importance, then at least the South East region should be considered as a key area for Acropora species conservation, and should be included in the Chinchorro Bank management plan. 相似文献
126.
Coral reef marine protected areas (MPA) are widely distributed around the globe for social and ecological reasons. Relatively
few of these MPAs are well managed. This review examines the governance of coral reef MPAs and the means to improve coral
reef MPA management. It highlights common governance challenges, such as confused goals, conflict, and unrealistic attempts
to scale up beyond institutional capacity. Recommendations, based on field experience and empirical evidence from around the
world, are made for best practices at various stages of MPA implementation.
相似文献
A. T. WhiteEmail: |
127.
Marine conservation programs in Oceania are increasingly turning to precautionary and adaptive management, particularly approaches
which emphasize local participation and customary management. Although the application of community-based natural resource
management is widespread in the region, the full integration of local knowledge and practices into the design, implementation,
and monitoring of community-based conservation programs has been limited. There is also little empirical data to show whether
or not community-based conservation projects are meeting their stated objectives. This paper summarizes an integrated method
for selecting Marine Protected Area (MPA) sites and presents empirical evidence that illustrates how an MPA that was largely
conceived using indigenous ecological knowledge and existing sea tenure governance (i.e., customary management practices),
as part of a regional precautionary and adaptive community-based management plan, is showing signs of biological and social
success. More generally, the paper shows how hybrid natural and social research approaches in tandem with customary management
for designing MPAs can protect coral reefs in Oceania. 相似文献
128.
129.
This study reports the state and causes of eutrophication in the Portuguese continental Exclusive Economic Zone (EEZ), during a 14-year period (1995–2008), following the European Marine Strategy Framework Directive (MSFD) and using the trophic index TRIX for an integrated evaluation of indicators of eutrophication, and identifies areas where monitoring is needed to improve the eutrophication assessment. A non-continuous dataset for the 8 indicators specified by the MSFD for eutrophication assessment was used, including published and grey data. Eutrophication indicators were validated and thresholds reviewed, considering regional differences. The diatom:flagellate ratio was found a poor indicator of eutrophication as shifts in the diatom:flagellate ratio naturally occur associated with alternating water column turbulence and upwelling, and stratification, and therefore, could not be associated with anthropogenic nutrient enrichment effects. Assessment areas were, as a whole, classified as non-problem areas concerning eutrophication. Although nutrient enrichment was observed in coastal waters, related to river plume influence, nutrient enrichment direct and indirect effects were generally not detectable, possibly due to water column dispersion and mixing processes. Only occasionally, mild eutrophication was found in specific areas under the influence of major river (Douro, Vouga and Guadiana) plumes, associated with high nutrient and phytoplankton biomass levels and seagrass decline, which indicates the need for directed monitoring on eutrophication in those areas. 相似文献
130.
Jacqueline W.A. Scheepmaker Jan van de Kassteele 《Biocontrol Science and Technology》2011,21(10):1225-1242
Our aim was to investigate the non-target effects on soil micro-organisms in agricultural environments caused by chemical control agents (CCAs) and microbial biocontrol agents (mBCAs), including the recovery from these effects. This was a desk study in which quantifiable endpoints, such as numbers of colony forming units (CFU), were derived from a series of studies and the combined data then analysed with a meta-regression analysis. Three analyses of the same dataset were performed. The first analysis, which was performed at the level of the CCAs and mBCAs in general, revealed that the effects of CCAs differed significantly from those of mBCAs. The second analysis, which included the type of non-target group (bacteria, fungi, actinomycetes, and protozoa) as additional input, revealed that mBCAs have greater effects than CCAs on fungi at study initiation, that CCAs had greater effects than mBCAs on bacteria and protozoa and that when effects were measured, recovery occurred within 100 days post-treatment initiation. The final analysis, which included the type of CCA (fungicide, insecticide, herbicide) or mBCA (antagonist) as additional input, revealed that (1) antagonists had a greater effect on fungi than insecticides and fungicides, (2) insecticides and to a lesser extent fungicides had a larger effect on bacteria than fungicides and antagonists, and (3) recovery of the CFU occurred within 100 days for all types of pesticides, mBCAs as well as CCAs, and for all non-target groups. The findings are discussed in view of the regulatory context of admittance of mBCAs to the market. 相似文献