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101.
Elissavet Nikolaou Ino Agrafioti Michael Stumpf Janet Quinn Ian Stansfield Alistair JP Brown 《BMC evolutionary biology》2009,9(1):44
Background
Microbes must sense environmental stresses, transduce these signals and mount protective responses to survive in hostile environments. In this study we have tested the hypothesis that fungal stress signalling pathways have evolved rapidly in a niche-specific fashion that is independent of phylogeny. To test this hypothesis we have compared the conservation of stress signalling molecules in diverse fungal species with their stress resistance. These fungi, which include ascomycetes, basidiomycetes and microsporidia, occupy highly divergent niches from saline environments to plant or mammalian hosts. 相似文献102.
Georgia Tsagkogeorga Xavier Turon Russell R Hopcroft Marie-Ka Tilak Tamar Feldstein Noa Shenkar Yossi Loya Dorothée Huchon Emmanuel JP Douzery Frédéric Delsuc 《BMC evolutionary biology》2009,9(1):187-16
Background
Tunicates have been recently revealed to be the closest living relatives of vertebrates. Yet, with more than 2500 described species, details of their evolutionary history are still obscure. From a molecular point of view, tunicate phylogenetic relationships have been mostly studied based on analyses of 18S rRNA sequences, which indicate several major clades at odds with the traditional class-level arrangements. Nonetheless, substantial uncertainty remains about the phylogenetic relationships and taxonomic status of key groups such as the Aplousobranchia, Appendicularia, and Thaliacea. 相似文献103.
GMDD: a database of GMO detection methods 总被引:1,自引:0,他引:1
Wei Dong Litao Yang Kailin Shen Banghyun Kim Gijs A Kleter Hans JP Marvin Rong Guo Wanqi Liang Dabing Zhang 《BMC bioinformatics》2008,9(1):260
Background
Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed. 相似文献104.
105.
Jawahir M Nicholas SA Coughlan K Sumbayev VV 《Apoptosis : an international journal on programmed cell death》2008,13(12):1410-1416
Nitric oxide (NO) is a reactive secondary mediator, which has been found to participate in cell cycle regulation and apoptosis
in myeloid macrophages, the key effectors of inflammatory and innate immune responses. However, the molecular mechanisms of
nitric oxide-induced death of myeloid macrophages are not well understood. In this study we have found that NO derived from
S-nitrosoglutathione (GSNO) activates ASK1 in THP-1 human myeloid macrophages in a concentration and time-dependent manner.
It also induces accumulation of HIF-1α protein in a concentration-dependent manner, which peaks at 4 h of exposure to 1 mM
GSNO. GSNO does not affect the level of HIF-1α mRNA as detected by the RT-PCR. In addition, GSNO was found to induce accumulation
of p53 in normal but not HIF-1α knockdown THP-1 cells, where expression of this protein was silenced by specific siRNA. It
has also been found that GSNO-mediated accumulation of p53 depends on activation of ASK1 since no GSNO-induced p53 stabilisation
was observed in THP-1 cells transfected with dominant-negative form of this kinase. However, in both HIF-1α knockdown THP-1
cells and those transfected with the dominant-negative form of ASK1, GSNO was able to induce cell death as detected by the
MTS cell viability assay leading to an increase in release of LDH. 相似文献
106.
Earth’s Precambrian Era as a Common Evolutionary Theme in Two Art Courses at Winona State University
Bruno Borsari Robin Richardson Anne Scott Plummer Mary Coughlan Jennifer Anderson 《Evolution》2008,1(2):172-178
A multidisciplinary approach to teaching was adopted in two art courses by employing concepts of evolutionary biology with
a focus on the Precambrian Era. This knowledge served to help students create original art pieces while learning and applying
concepts that are often challenging to non-science majors. This evaluation report shows the efficacy of our teaching methods
and will hopefully inspire educators to creatively enhance the teaching of evolution across the curriculum. 相似文献
107.
Thomas C. Kelly D. Paddy Sleeman Neil E. Coughlan Eileen Dillane Michael J.A. O’Callaghan 《European Journal of Wildlife Research》2017,63(1):23
Globally, collisions between wildlife and aircraft are a serious threat to aviation safety. While reported collisions have increased in recent years, the impact of these collisions on air safety is rarely quantified. Here, we report all bat collisions (bat strikes) with civil aircraft known to have occurred in the Republic of Ireland over the 10-year interval, 2006–2015. Morphological and/or DNA identification techniques were used to identify chiropteran specimens to species level. In total, carcasses or remains from five bat strikes—three Leisler’s Nyctalus leisleri, one Soprano Pipistrelle Pipistrellus pygmaeus, and one Natterer’s Myotis nattereri—were recovered. The collisions are discussed in the context of (a) the rate of chiropteran strikes in relation to the number of civil aircraft movements and (b) possible damage caused to aircraft. Overall, however, bat strikes with aircraft appear to have a negligible effect on civil aircraft safety. 相似文献
108.
109.
Widespread generalist clones are associated with range and niche expansion in allopolyploids of Pacific Northwest Hawthorns (Crataegus L.)
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Range and niche expansion are commonly associated with transitions to asexuality, polyploidy and hybridity (allopolyploidy) in plants. The ability of asexual polyploids to colonize novel habitats may be due to widespread generalist clones, multiple ecologically specialized clones, or may be a neutral by‐product of multiple, independent origins of asexual polyploids throughout the range. We have quantified niche size and divergence for hawthorns of the Pacific Northwest using data from herbarium vouchers with known cytotypes. We find that all polyploid niches diverge from that of the diploid range, and allopolyploids have the broadest niches. Allotetraploids have the largest niche and the widest geographic distribution. We then assessed the genetic mechanism of range expansion by surveying the ecological and geographic distribution of genotypes within each cytotype from sites in which fine‐scale habitat assessments were completed. We find no isolation by either geographic or ecological distance in allopolyploids, suggesting high dispersal and colonization ability. In contrast, autotriploids and diploids show patterns of isolation by geographic distance. We also compared the geographic and ecological distributions of clonal genotypes with those of randomly drawn sites of the most widespread cytotype. We found that most clones are geographically widespread and occur in a variety of habitats. We interpret these findings to suggest that patterns of range and niche expansion in Pacific Northwest Hawthorns may stem from these widespread, ecologically generalist clones of hybrid origin. 相似文献
110.