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101.
Charles D Criscione Claudia LL Valentim Hirohisa Hirai Philip T LoVerde Timothy JC Anderson 《Genome biology》2009,10(6):R71-13
Background
Schistosoma mansoni is a blood fluke that infects approximately 90 million people. The complete life cycle of this parasite can be maintained in the laboratory, making this one of the few experimentally tractable human helminth infections, and a rich literature reveals heritable variation in important biomedical traits such as virulence, host-specificity, transmission and drug resistance. However, there is a current lack of tools needed to study S. mansoni's molecular, quantitative, and population genetics. Our goal was to construct a genetic linkage map for S. mansoni, and thus provide a new resource that will help stimulate research on this neglected pathogen. 相似文献102.
Synemin isoforms during mouse development: Multiplicity of partners in vascular and neuronal systems
Araksya Izmiryan Claudio Areias Franco Denise Paulin Zhenlin Li Zhigang Xue 《Experimental cell research》2009,315(5):769-2552
The intermediate filament (IF) synemin gene encodes three IF proteins (H 180, M 150, L 41 kDa isoforms) with overlapping distributions. In the present study we analysed the mRNA and protein expression of each isoform in developing mouse embryos. Synemin M mRNA was present as early as E5 with vimentin and nestin. Synemin H was found later at E9 in the nervous system and mesodermic derivatives concomitantly with angiogenesis, somitogenesis and the migration of neural crest cells. Synemin L appeared later in neurons at E15. Furthermore, the synemin isoforms required different IF partners depending on the cell type to form filamentous structures. In endothelial cells, synemin H/M were found associated with vimentin and were absent in vimentin-null mice. In neurons of the peripheral nervous system of E15 embryos, synemin H/M or L were co-expressed with neurofilament, peripherin and internexin. In adult mice, our data support the existence of different subpopulations of neurons within the dorsal root ganglia: one composed of small neurons containing synemin H/M and peripherin, and another composed of large neurons containing synemin L and neurofilaments. Axons devoid of neurofilaments from mutant mice (NFHLacZ) showed an absence of the L isoform but contained H/M isoforms with peripherin. 相似文献
103.
Filipe M. Areias Jose Brea Elisabet Gregori-Puigjané Magdi E.A. Zaki M. Alice Carvalho Eduardo Domínguez Hugo Gutiérrez-de-Terán M. Fernanda Proença María I. Loza Jordi Mestres 《Bioorganic & medicinal chemistry》2010,18(9):3043-3052
One of the grand challenges in chemical biology is identifying a small-molecule modulator for each individual function of all human proteins. Instead of targeting one protein at a time, an efficient approach to address this challenge is to target entire protein families by taking advantage of the relatively high levels of chemical promiscuity observed within certain boundaries of sequence phylogeny. We recently developed a computational approach to identifying the potential protein targets of compounds based on their similarity to known bioactive molecules for almost 700 targets. Here, we describe the direct identification of novel antagonists for all four adenosine receptor subtypes by applying our virtual profiling approach to a unique synthesis-driven chemical collection composed of 482 biologically-orphan molecules. These results illustrate the potential role of in silico target profiling to guide efficiently screening campaigns directed to discover new chemical probes for all members of a protein family. 相似文献
104.
105.
Harriëtte Riese Tanja GM Vrijkotte Piet Meijer Cees Kluft Eco JC de Geus 《BMC cardiovascular disorders》2002,2(1):9-12
Background
Serum C-reactive protein (CRP) has been identified in prospective epidemiological research as an independent risk marker for cardiovascular disease. In this paper, short-term biological variation of CRP is documented and a strategy to test the reliability of a single CRP sample is proposed. 相似文献106.
107.
Keyur Doolabh Lucius Caviola Julian Savulescu Michael Selgelid Dominic JC Wilkinson 《Developing world bioethics》2017,17(3):173-204
The 2016 outbreak of the Zika arbovirus was associated with large numbers of cases of the newly‐recognised Congenital Zika Syndrome (CZS). This novel teratogenic epidemic raises significant ethical and practical issues. Many of these arise from strategies used to avoid cases of CZS, with contraception in particular being one proposed strategy that is atypical in epidemic control. Using contraception to reduce the burden of CZS has an ethical complication: interventions that impact the timing of conception alter which people will exist in the future. This so‐called ‘non‐identity problem’ potentially has significant social justice implications for evaluating contraception, that may affect our prioritisation of interventions to tackle Zika. This paper combines ethical analysis of the non‐identity problem with empirical data from a novel survey about the general public's moral intuitions. The ethical analysis examines different perspectives on the non‐identity problem, and their implications for using contraception in response to Zika. The empirical section reports the results of an online survey of 93 members of the US general public exploring their intuitions about the non‐identity problem in the context of the Zika epidemic. Respondents indicated a general preference for a person‐affecting intervention (mosquito control) over an impersonal intervention (contraception). However, their responses did not appear to be strongly influenced by the non‐identity problem. Despite its potential philosophical significance, we conclude from both theoretical considerations and analysis of the attitudes of the community that the non‐identity problem should not affect how we prioritise contraception relative to other interventions to avoid CZS. 相似文献
108.
Gutierrez A del Rio JC Martinez MJ Martinez AT 《Applied and environmental microbiology》1999,65(4):1367-1371
Solid-state fermentation of eucalypt wood with several fungal strains was investigated as a possible biological pretreatment for decreasing the content of compounds responsible for pitch deposition during Cl2-free manufacture of paper pulp. First, different pitch deposits were characterized by gas chromatography (GC) and GC-mass spectrometry (MS). The chemical species identified arose from lipophilic wood extractives that survived the pulping and bleaching processes. Second, a detailed GC-MS analysis of the lipophilic fraction after fungal treatment of wood was carried out, and different degradation patterns were observed. The results showed that some basidiomycetes that decreased the lipophilic fraction also released significant amounts of polar extractives, which were identified by thermochemolysis as originating from lignin depolymerization. Therefore, the abilities of fungi to control pitch should be evaluated after analysis of compounds involved in deposit formation and not simply by estimating the decrease in the total extractive content. In this way, Phlebia radiata, Funalia trogii, Bjerkandera adusta, and Poria subvermispora strains were identified as the most promising organisms for pitch biocontrol, since they degraded 75 to 100% of both free and esterified sterols, as well as other lipophilic components of the eucalypt wood extractives. Ophiostoma piliferum, a fungus used commercially for pitch control, hydrolyzed the sterol esters and triglycerides, but it did not appear to be suitable for eucalypt wood treatment because it increased the content of free sitosterol, a major compound in pitch deposits. 相似文献
109.
Phylogenetic utility of elongation factor-1 alpha in noctuoidea (Insecta: Lepidoptera): the limits of synonymous substitution 总被引:2,自引:1,他引:1
Mitchell A; Cho S; Regier JC; Mitter C; Poole RW; Matthews M 《Molecular biology and evolution》1997,14(4):381-390
To test its phylogenetic utility, nucleotide sequence variation in a
1,240-bp fragment of the elongation factor-1 alpha (EF-1 alpha) gene was
examined in 49 moth species representing the major groups of the
superfamily Noctuoidea. Both parsimony and distance analyses supported the
monophyly of nearly all groups for which there are clear morphological
synapomorphies. Clades of subfamily rank and lower, probably mid-Tertiary
and younger, were strongly supported. The third codon position contains 88%
of variable sites, and approaches saturation at approximately 20% sequence
divergence, possibly due to among-site rate heterogeneity and composition
bias; higher divergences occur only in association with shifts in
composition. Surprisingly, the few nonsynonymous changes appear no more
phylogenetically reliable than synonymous changes. Signal strength for
basal divergences is weak and fails to improve with character weighting;
thus, dense taxon sampling is probably needed for strong inference from
EF-1 alpha regarding deeper splits in Noctuoidea (probably early Tertiary).
EF-1 alpha synonymous changes show promise for phylogeny reconstruction
within Noctuidae and other groups of Tertiary age.
相似文献
110.
Molecular phylogeny of the major arthropod groups indicates polyphyly of crustaceans and a new hypothesis for the origin of hexapods 总被引:18,自引:6,他引:12
A phylogeny of the arthropods was inferred from analyses of amino acid
sequences derived from the nuclear genes encoding elongation factor-1 alpha
and the largest subunit of RNA polymerase II using maximum- parsimony,
neighbor-joining, and maximum-likelihood methods. Analyses of elongation
factor-1 alpha from 17 arthropods and 4 outgroup taxa recovered many
arthropod clades supported by previous morphological studies, including
Diplopoda, Myriapoda, Insecta, Hexapoda, Branchiopoda (Crustacea), Araneae,
Tetrapulmonata, Arachnida, Chelicerata, and Malacostraca (Crustacea).
However, counter to previous studies, elongation factor-1 alpha placed
Malacostraca as sister group to the other arthropods. Branchiopod
crustaceans were found to be more closely related to hexapods and myriapods
than to malacostracan crustaceans. Sequences for RNA polymerase II were
obtained from 11 arthropod taxa and were analyzed separately and in
combination with elongation factor-1 alpha. Results from these analyses
were concordant with those derived from elongation factor-1 alpha alone and
provided support for a Hexapoda/Branchiopoda clade, thus arguing against
the monophyly of the traditionally defined Atelocerata (Hexapoda +
Myriapoda).
相似文献