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991.
992.
Understanding factors that influence local community support for conservation projects is critical to their success. Perceptions of wildlife are particularly important in countries where people rely heavily on natural resources for their survival, as is the case in Madagascar. Renowned as one of the “hottest” regions for global biodiversity, Madagascar hosts an exceptional assemblage of lemurs. Yet little is known concerning the knowledge and perceptions of local people toward lemurs. The Lake Alaotra gentle lemur (Hapalemur alaotrensis) is classified as Critically Endangered on the IUCN Red List and restricted to marsh habitat in the Lake Alaotra New Protected Area. Habitat destruction and hunting have brought the lemur to the brink of extinction. In this study we characterize local people’s knowledge, awareness, and perceptions of Hapalemur alaotrensis. We conducted an initial survey with 180 participants in 6 villages with varying distance to Park Bandro, a high-priority conservation zone. During a second survey, we interviewed 50 people in the village adjacent to the park. Our findings demonstrate that fishers are the most knowledgeable local resource users despite having the lowest education levels, and they also are the most concerned with the endemic lemur’s decline. There is a link between environmental awareness and distance in both a literal and figurative sense; the more often people encounter Hapalemur alaotrensis, the more they know about it, and the more likely they are to be concerned about its future. Our study further shows that despite this concern, subsistence is prioritized over conservation in the Alaotra region. Ecological knowledge in the fishers’ communities is a valuable resource that can benefit the conservation of Hapalemur alaotrensis and its marshland habitat if conservation planning and management can align the resource users’ concerns and livelihood needs with biodiversity values.  相似文献   
993.
In this publication, we review the biology, ecology, invasion history, impacts and management options of Emerald ash borer (EAB) Agrilus plannipennis, with a particular focus on its invasion in Europe. Agrilus planipennis (EAB) is a wood‐boring beetle native to East Asia. Having caused massive damages on ash species in North America in the last decades, it was first recorded in Europe in 2003 in Russia (Moscow). All ash (Fraxinus) species native to Europe and North America are known to be susceptible to EAB attacks, which cause high tree mortality even among formerly healthy trees. Recorded expansion rates are between 2.5 and 80 km/year in North America and between 13 and 41 km/year in European Russia. Given current expansion rates, EAB is expected to reach Central Europe within 15–20 years. A combination of mechanical, biological and chemical control and phytosanitary measures may reduce its impact, which nevertheless most likely will be substantial. There is an urgent need to identify native enemies in Europe, to test suitable biocontrol agents and to develop early detection and management measures. Although it is obvious that EAB will become a major pest in Europe, early and dedicated response will likely be able to reduce the level of ash mortality, and thus improve the opportunity for long‐term survival of ash as an important component in European forests.  相似文献   
994.
995.
Here, we characterize the Aspergillus fumigatus homologue ncsA Neuronal Calcium Sensor. We showed that ncsA is not an essential gene and ?ncsA growth was decreased in the presence of EGTA and SDS. Furthermore, the ?ncsA mutant is more resistant to calcium chloride. NcsA:mRFP localizes to the cytoplasm and its cellular localization is not affected by the cellular response to either calcium chloride or EGTA. The ?ncsA mutant strain is more sensitive to voriconazole, itraconazole, and amphotericin. Polar growth in the ΔncsA mutant was also considerably more affected by lovastatin than in the wild type strain. The Spitzenkörper can be visualized in both strains and although the vacuolar system does not seem to be very different, there is an increase in the staining intensity on the germling surface of the ?ncsA strain. NcsA promotes pmcA and pmcB expression and therefore there is a reduced expression of these ion pumps in the ΔncsA mutant background, and also of other genes involved in the response to calcium in A. fumigatus. The ncsA inactivation mutation is not causing loss of virulence in a low dose murine infection when compared to the corresponding wild type strain.  相似文献   
996.
Social waves in giant honeybees repel hornets   总被引:3,自引:0,他引:3  
Giant honeybees (Apis dorsata) nest in the open and have evolved a plethora of defence behaviors. Against predatory wasps, including hornets, they display highly coordinated Mexican wave-like cascades termed 'shimmering'. Shimmering starts at distinct spots on the nest surface and then spreads across the nest within a split second whereby hundreds of individual bees flip their abdomens upwards. However, so far it is not known whether prey and predator interact and if shimmering has anti-predatory significance. This article reports on the complex spatial and temporal patterns of interaction between Giant honeybee and hornet exemplified in 450 filmed episodes of two A. dorsata colonies and hornets (Vespa sp.). Detailed frame-by-frame analysis showed that shimmering elicits an avoidance response from the hornets showing a strong temporal correlation with the time course of shimmering. In turn, the strength and the rate of the bees' shimmering are modulated by the hornets' flight speed and proximity. The findings suggest that shimmering creates a 'shelter zone' of around 50 cm that prevents predatory wasps from foraging bees directly from the nest surface. Thus shimmering appears to be a key defence strategy that supports the Giant honeybees' open-nesting life-style.  相似文献   
997.
An estimated one-third of all proteins in higher eukaryotes are regulated by phosphorylation by protein kinases (PKs). Although plant genomes encode more than 1000 PKs, the substrates of only a small fraction of these kinases are known. By mass spectrometry of peptides from cytoplasmic- and nuclear-enriched fractions, we determined 303 in vivo phosphorylation sites in Arabidopsis proteins. Among 21 different PKs, 12 were phosphorylated in their activation loops, suggesting that they were in their active state. Immunoblotting and mutational analysis confirmed a tyrosine phosphorylation site in the activation loop of a GSK3/shaggy-like kinase. Analysis of phosphorylation motifs in the substrates suggested links between several of these PKs and many target sites. To perform quantitative phosphorylation analysis, peptide arrays were generated with peptides corresponding to in vivo phosphorylation sites. These peptide chips were used for kinome profiling of subcellular fractions as well as H 2O 2-treated Arabidopsis cells. Different peptide phosphorylation profiles indicated the presence of overlapping but distinct PK activities in cytosolic and nuclear compartments. Among different H 2O 2-induced PK targets, a peptide of the serine/arginine-rich (SR) splicing factor SCL30 was most strongly affected. SRPK4 (SR protein-specific kinase 4) and MAPKs (mitogen-activated PKs) were found to phosphorylate this peptide, as well as full-length SCL30. However, whereas SRPK4 was constitutively active, MAPKs were activated by H 2O 2. These results suggest that SCL30 is targeted by different PKs. Together, our data demonstrate that a combination of mass spectrometry with peptide chip phosphorylation profiling has a great potential to unravel phosphoproteome dynamics and to identify PK substrates.  相似文献   
998.
Heat shock protein hsp27 is a molecular chaperone and identification of hsp27-binding proteins might help to elucidate its functional role in keratinocyte biology. In the present investigation we used a human epidermal cell carcinoma cell line (A431) transfected with hsp27 (A431/16) to study interference between hsp27 protein and other proteins. Immunoprecipitation experiments with anti-hsp27 antibody revealed a multicomponent complex when analysed by silver staining. By immunoblotting analysis we could demonstrate that hsp27 associates with actin, the mutant form of p53, hsp70 and hsp90. Immunofluorescence analysis showed a co-localization between hsp27 and p53, hsp70 and hsp90. To control for the specificity of the observed interactions, immuno-precipitations with antibodies to actin, p53, hsp70 and hsp90 respectively, were performed. All of the tested proteins demonstrated a coimmunoprecipitation with hsp27. We conclude that hsp27, like the other heat shock proteins, is part of a complex system of molecular chaperones in epidermal keratinocytes.  相似文献   
999.
1000.
Thirty years ago, Peter Mitchell won the Nobel Prize for proposing how electrical and proton gradients across bioenergetic membranes were the energy coupling intermediate between photosynthetic and respiratory electron transfer and cellular activities that include ATP production. A high point of his thinking was the development of the Q-cycle model that advanced our understanding of cytochrome bc 1. While the principle tenets of his Q-cycle still hold true today, Mitchell did not explain the specific mechanism that allows the Qo site to perform this Q-cycle efficiently without undue energy loss. Though much speculation on Qo site mode of molecular action and regulation has been introduced over the 30 years after Mitchell collected his Prize, no single mechanism has been universally accepted. The mystery behind the Qo site mechanism remains unsolved due to elusive kinetic intermediates during Qo site electron transfer that have not been detected spectroscopically. Therefore, to reveal the Qo mechanism, we must look beyond traditional steady-state experimental approaches by changing cytochrome bc 1 thermodynamics and promoting otherwise transient Qo site redox states. Invited paper to special issue “Peter Mitchell 30th anniversary” for JBB.  相似文献   
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