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131.
Nexø BA Christensen T Frederiksen J Møller-Larsen A Oturai AB Villesen P Hansen B Nissen KK Laska MJ Petersen TS Bonnesen S Hedemand A Wu T Wang X Zhang X Brudek T Maric R Søndergaard HB Sellebjerg F Brusgaard K Kjeldbjerg AL Rasmussen HB Nielsen AL Nyegaard M Petersen T Børglum AD Pedersen FS 《PloS one》2011,6(2):e16652
We have investigated the role of human endogenous retroviruses in multiple sclerosis by analyzing the DNA of patients and controls in 4 cohorts for associations between multiple sclerosis and polymorphisms near viral restriction genes or near endogenous retroviral loci with one or more intact or almost-intact genes. We found that SNPs in the gene TRIM5 were inversely correlated with disease. Conversely, SNPs around one retroviral locus, HERV-Fc1, showed a highly significant association with disease. The latter association was limited to a narrow region that contains no other known genes. We conclude that HERV-Fc1 and TRIM5 play a role in the etiology of multiple sclerosis. If these results are confirmed, they point to new modes of treatment for multiple sclerosis. 相似文献
132.
The 18.8 kDa chitin-binding protein CBP21 from Serratia marcescens has been isotopically labeled and recombinantly expressed. In this paper, we report the 1H, 13C, 15N resonance assignment of CBP21. 相似文献
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Rainbow tags: a visual tag system for recombinant protein expression and purification 总被引:1,自引:0,他引:1
Visualization systems for tracking proteins are standard experimental tools in most areas of biological research apart from protein purification. Here, we have sought to plug this gap by producing red and yellow visual tags using the heme-binding domain of mosquito cytochrome b5 and the flavin mononucleotide (FMN)-binding domain of human P450 reductase. Tests with colorless glutathione-S-transferase (GST) show them to be simple and effective tools for visually identifying correctly folded protein and tracking protein molecules through protein expression and purification. Furthermore, the characteristic absorbance signatures of the colored tags can be used to quantify protein concentrations directly, which allows purification to be linked to colorimetric detection. This technology, which we call Rainbow Tagging, facilitates expression and downstream processing of recombinant proteins, paving the way for the development of automated high-throughput protein expression systems. 相似文献
137.
Kühn I Iversen A Finn M Greko C Burman LG Blanch AR Vilanova X Manero A Taylor H Caplin J Domínguez L Herrero IA Moreno MA Möllby R 《Applied and environmental microbiology》2005,71(9):5383-5390
Vancomycin-resistant enterococci (VRE) in Europe are thought to have emerged partly due to the use of the glycopeptide avoparcin in animal husbandry. We compared the occurrence of VRE in geographical regions of Europe in which until 1997 large amounts of avoparcin were used (Spain, United Kingdom, and Denmark) with the occurrence of VRE in Sweden, where avoparcin was banned in 1986. We also studied the relatedness between VRE strains from different regions and habitats. In total, 2,580 samples were collected from humans, animals, and the environment (soil, sewage, recipient water). VRE resistant to 20 microg/ml vancomycin were identified in 8.2% of the samples and were found most frequently in raw and treated urban sewage samples (means, 71% and 36% of the samples, respectively), pig manure (17%), and hospital sewage (16%). The proportions of VRE-positive sewage samples were similar in Sweden, Spain, and the United Kingdom, whereas pig feces and manure were more often positive in Spain than in Sweden (30% versus 1%). Most VRE were Enterococcus faecium carrying vanA, and computerized biochemical phenotyping of the isolates of different ecological origins showed a high degree of polyclonality. In conclusion, it seems that animal-associated VRE probably reflect the former use of avoparcin in animal production, whereas VRE in human-associated samples may be a result of antibiotic use in hospitals. Since there seems to be a reservoir of the resistance genes in all countries studied, precautions must be taken to limit the use of antibiotics and antibiotic-like feed additives. 相似文献
138.
Successful purification of biological molecules by affinity chromatography requires the attachment of desired ligands to biocompatible chromatographic supports. The Cu(I)-catalyzed cycloaddition of azides and alkynes-the premier example of "click chemistry"-is an efficient way to make covalent connections among diverse molecules and materials. Both azide and alkyne units are highly selective in their reactivity, being inert to most chemical functionalities and stable to wide ranges of solvent, temperature, and pH. We show that agarose beads bearing alkyne and azide groups can be easily made and are practical precursors to functionalized agarose materials for affinity chromatography. 相似文献
139.
Finn?DanielsenEmail author Neil?D.?Burgess Andrew?Balmford 《Biodiversity and Conservation》2005,14(11):2507-2542
Monitoring of biodiversity and resource use by professional scientists is often costly and hard to sustain, especially in
developing countries, where financial resources are limited. Moreover, such monitoring can be logistically and technically
difficult and is often perceived to be irrelevant by resource managers and the local communities. Alternatives are emerging,
carried out at a local scale and by individuals with little formal education. The methods adopted span a spectrum, from participatory
monitoring where aims and objectives are defined by the community, to ranger-based monitoring in protected areas. What distinguishes
these approaches is that local people or local government staff are directly involved in data collection and (in most instances)
analysis. In this issue of Biodiversity and Conservation, 15 case studies examine whether these new approaches can address
the limitations of professional monitoring in developing countries. The case studies evaluate ongoing locally-based monitoring
schemes involving more than 1500 community members in 13 countries. The papers are based on a symposium held in Denmark in
April 2004 (www. monitoringmatters.org). Here, we review how the case studies shed light on the following key issues concerning
locally-based methods: cost, sustainability, their ability to detect true local or larger-scale trends, their links to management
decisions and action, and the empowerment of local constituencies. Locally-based monitoring appears to be consistently cheap
relative to the costs of management and of professional monitoring, even though the start-up costs can be high. Most local
monitoring schemes are still young and thus their chances of being sustained over the longer term are not yet certain. However,
we believe their chances of surviving are better than many professional schemes, particularly when they are institutionalised
within existing management structures, and linked to the delivery of ecosystem goods or services to local communities. When
properly designed, local schemes yield locally relevant results that can be as reliable as those derived from professional
monitoring. Many management decisions emanate from local schemes. The decisions appear to be taken promptly, in response to
immediate threats to the environment, and often lead to community-based actions to protect habitats, species or the local
flow of ecosystem benefits; however, few local schemes have so far led to actions beyond the local scale. Locally-based monitoring
schemes often reinforce existing community-based resource management systems and lead to change in the attitude of locals
towards more environmentally sustainable resource management. Locally-derived data have considerable unexplored potential
to elucidate global patterns of change in the status of populations and habitats, the services they provide, and the threats
they face, but more effort is needed to develop effective modalities for feeding locally-derived data up to national and international
levels. 相似文献
140.
Finn?DanielsenEmail author Arne E.?Jensen Phillip A.?Alviola Danilo S.?Balete Marlynn?Mendoza Anson?Tagtag Carlo?Custodio Martin?Enghoff 《Biodiversity and Conservation》2005,14(11):2633-2652
Biodiversity monitoring is criticized for being insufficiently relevant to the needs of managers and ineffective in integrating information into decision-making. We examined conservation management interventions resulting from 2½ years of monitoring by 97 rangers and 350 community volunteers over 1 million hectares of Philippine protected areas. Before this monitoring scheme was established, there was little collaboration between local people and park authorities, and park monitoring was restricted to assessments of the quantity of extracted timber. As a result of the scheme, 156 interventions were undertaken in terrestrial, marine and freshwater ecosystems. In total 98% of these interventions were meaningful and justified, 47% targeted the three most serious threats to biodiversity at the site, and 90% were implemented without external support, suggesting that the interventions were relevant and could be sustained over time at the local level. The mean time from sampling to decision-making was only 97 days, probably because 82% of the interventions were initiated by the same people and institutions that had compiled the underlying data, bypassing potential government bureaucracy. Many of the interventions were jointly undertaken by community members and the management authorities or consisted of local bylaws in support of park management. As a result of the monitoring, indigenous resource use regulation schemes were re-established with government recognition in several parks. The monitoring led to more diversified and realistic management responses on the part of the authorities, including a more socially acceptable and effective approach to enforcement. Of the four field monitoring techniques used, the most participatory one generated more interventions aimed at ensuring a continued resource supply for local communities (χ23 = 69.1, p <0.01). Although this suggests that the interest of community members is associated with their possibilities to influence the flow of ecosystem goods and services, the 156 interventions targeted, directly or indirectly, all known globally threatened species of mammals, birds and butterflies in the parks. 相似文献