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141.
Shai Bel 《Autophagy》2018,14(4):719-721
Secretion of antimicrobial proteins is an important host defense mechanism against bacteria, yet how secretory cells maintain function during bacterial invasion has been unclear. We discovered that Paneth cells, specialized secretory cells in the small intestine, react to bacterial invasion by rerouting a critical secreted antibacterial protein through a macroautophagy/autophagy-based secretion system termed secretory autophagy. Mice harboring a mutation in an essential autophagy gene, a mutation which is common in Crohn disease patients, cannot reroute their antimicrobial cargo during bacterial invasion and thus have compromised innate immunity. We showed that this alternative secretion system is triggered by both a cell-intrinsic mechanism, involving the ER stress response, and a cell-extrinsic mechanism, involving subepithelial innate immune cells. Our findings uncover a new role for secretory autophagy in host defense and suggest how a mutation in an autophagy gene can predispose individuals to Crohn disease. 相似文献
142.
Genome‐wide signatures of flowering adaptation to climate temperature: Regional analyses in a highly diverse native range of Arabidopsis thaliana
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Daniel Tabas‐Madrid Belén Méndez‐Vigo Noelia Arteaga Arnald Marcer Alberto Pascual‐Montano Detlef Weigel F. Xavier Picó Carlos Alonso‐Blanco 《Plant, cell & environment》2018,41(8):1806-1820
Current global change is fueling an interest to understand the genetic and molecular mechanisms of plant adaptation to climate. In particular, altered flowering time is a common strategy for escape from unfavourable climate temperature. In order to determine the genomic bases underlying flowering time adaptation to this climatic factor, we have systematically analysed a collection of 174 highly diverse Arabidopsis thaliana accessions from the Iberian Peninsula. Analyses of 1.88 million single nucleotide polymorphisms provide evidence for a spatially heterogeneous contribution of demographic and adaptive processes to geographic patterns of genetic variation. Mountains appear to be allele dispersal barriers, whereas the relationship between flowering time and temperature depended on the precise temperature range. Environmental genome‐wide associations supported an overall genome adaptation to temperature, with 9.4% of the genes showing significant associations. Furthermore, phenotypic genome‐wide associations provided a catalogue of candidate genes underlying flowering time variation. Finally, comparison of environmental and phenotypic genome‐wide associations identified known (Twin Sister of FT, FRIGIDA‐like 1, and Casein Kinase II Beta chain 1) and new (Epithiospecifer Modifier 1 and Voltage‐Dependent Anion Channel 5) genes as candidates for adaptation to climate temperature by altered flowering time. Thus, this regional collection provides an excellent resource to address the spatial complexity of climate adaptation in annual plants. 相似文献
143.
Guillermo Rodríguez‐Hernández Inés González‐Herrero Carolin Walter Sara González de Tena‐Dávila Salma Parvin Oskar Haas Wilhelm Woessmann Martin Stanulla Martin Schrappe Martin Dugas Yasodha Natkunam Alberto Orfao Verónica Domínguez Belén Pintado Oscar Blanco Diego Alonso‐López Javier De Las Rivas Alberto Martín‐Lorenzo Rafael Jiménez Francisco Javier García Criado María Begoña García Cenador Izidore S Lossos Carolina Vicente‐Dueñas Arndt Borkhardt Julia Hauer Isidro Sánchez‐García 《The EMBO journal》2018,37(14)
144.
The lipid phosphatase Sac1 dephosphorylates phosphatidylinositol 4‐phosphate (PI4P), thereby holding levels of this crucial membrane signaling molecule in check. Sac1 regulates multiple cellular processes, including cytoskeletal organization, membrane trafficking and cell signaling. Here, we review the structure and regulation of Sac1, its roles in cell signaling and development and its links to health and disease. Remarkably, many of the diverse roles attributed to Sac1 can be explained by the recent discovery of its requirement at membrane contact sites, where its consumption of PI4P is proposed to drive interorganelle transfer of other cellular lipids, thereby promoting normal lipid homeostasis within cells. 相似文献
145.
Rosa Belén Mohedano del Pozo Margarita Rubio Alonso Mª Soledad Cuétara García 《Revista iberoamericana de micología》2018,35(3):117-122
Background
The role of culture-independent techniques (galactomannan, (1-3)-β-d-glucan) in the early diagnosis of invasive fungal diseases (IFD) is well assessed in hematological patients, but there are no clear conclusions in patients with chronic obstructive pulmonary disease (COPD).Aims
To study the usefulness of nonculture-based techniques in the diagnosis of IFD in COPD-patients at risk for IFD.Methods
A prospective observational study based on monitoring COPD patients at risk for IFD during 2007–2010 was carried out. The presence of galactomannan, (1-3)-β-d-glucan and an indirect immunofluorescence of Candida albicans germ tube specific antibodies (CAGTA) were performed.Results
Among 43 COPD patients, 16 (37.2%) were diagnosed with IFD: seven cases were proven IFD (five invasive candidemia – IC, one invasive aspergillosis – IA and a rhinocerebral zygomycosis) and nine probable IFD (seven IA and two IC). In the diagnosis of IC and IA, the negative predictive value (NPV) of (1-3)-β-d-glucan was 100%. Regarding CAGTA in IC, NPV was 96.2%. Finally, NPV of galactomannan in IA was 91.2%. The area under the ROC curve for (1-3)-β-d-glucan in IC and for the rest of the IFD cases was 0.86 (95% CI, 0.79–0.93) and 0.60 (95% CI, 0.43–0.77), for CAGTA in IC was 0.83 (95% CI, 0.74–0.91) and for galactomannan in IA was 0.71 (95% CI, 0.56–0.85). Positive (1-3)-β-d-glucan preceded the growth of Candida (average of 1.7 days) in blood culture.Conclusions
In COPD patients at risk for IFD the assayed techniques are especially useful to rule out the presence of IFD. 相似文献146.
How to tackle chemical communication? Relative proportions versus semiquantitative determination of compounds in lizard chemical secretions
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Roberto García‐Roa Jorge Sáiz Belén Gómara Pilar López José Martín 《Ecology and evolution》2018,8(4):2032-2040
Knowledge about chemical communication in some vertebrates is still relatively limited. Squamates are a glaring example of this, even when recent evidences indicate that scents are involved in social and sexual interactions. In lizards, where our understanding of chemical communication has considerably progressed in the last few years, many questions about chemical interactions remain unanswered. A potential reason for this is the inherent complexity and technical limitations that some methodologies embody when analyzing the compounds used to convey information. We provide here a straightforward procedure to analyze lizard chemical secretions based on gas chromatography coupled to mass spectrometry that uses an internal standard for the semiquantification of compounds. We compare the results of this method with those obtained by the traditional procedure of calculating relative proportions of compounds. For such purpose, we designed two experiments to investigate if these procedures allowed revealing changes in chemical secretions 1) when lizards received previously a vitamin dietary supplementation or 2) when the chemical secretions were exposed to high temperatures. Our results show that the procedure based on relative proportions is useful to describe the overall chemical profile, or changes in it, at population or species levels. On the other hand, the use of the procedure based on semiquantitative determination can be applied when the target of study is the variation in one or more particular compounds of the sample, as it has proved more accurate detecting quantitative variations in the secretions. This method would reveal new aspects produced by, for example, the effects of different physiological and climatic factors that the traditional method does not show. 相似文献
147.
Single step recombinant human growth hormone (rhGH) purification from milk by peptide affinity chromatography
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Soledad L. Saavedra María C. Martínez Ceron Silvana L. Giudicessi Guillermina Forno María Belén Bosco Mariela M. Marani Rosa Erra‐Balsells Fernando Albericio Osvaldo Cascone Silvia A. Camperi 《Biotechnology progress》2018,34(4):999-1005
Recombinant human growth hormone (rhGH) is used for the treatment of several pathologies, most of them related to growth. Although different expression systems can be used for its production, the milk from transgenic cows is one of the most interesting due to the high rhGH level achieved (5 g/L). We have designed and synthesized short peptides (9 or 10 amino acid long) using Fmoc chemistry and studied their ability to purify rhGH from milk once immobilized on an agarose support. Using spiked milk with the hormone as a sample, rhGH was purified with 88% yield and 92% purity in a single step with a fold purification of 4.5. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:999–1005, 2018 相似文献
148.
E. Richard Lourdes R. Desviat Belén Pérez Celia Pérez-Cerdá M. Ugarte 《Human genetics》1997,101(1):93-96
Propionyl-CoA carboxylase (PCC) is a mitochondrial, biotin-dependent enzyme involved in the catabolism of branched chain
amino acids, odd chain fatty acids, and other metabolites. PCC consists of non-identical subunits, α and β, encoded by the
PCCA and PCCB genes, respectively. Inherited deficiency of PCC due to mutations in either the PCCA or the PCCB gene results
in propionic acidemia (PA), a clinically heterogeneous disorder with a severe, often lethal, neonatal form, and a mild, later
onset form. To characterize PCCA gene mutations responsible for PCC deficiency, we analyzed RT-PCR products obtained from
cultured fibroblasts from Spanish PCC-α deficient patients. In three patients, smaller than normal PCR products were observed,
and sequence analysis revealed the deletion of a 54-bp exon in the cDNA. Sequencing of genomic DNA from these three patients
led to the identification of three novel mutations in the PCCA gene, two short deletions and one small insertion, adjacent
to short direct repeats, and all of them affecting the consensus splice sites of the skipped exon. These mutations, 1771IVS-2del9,
1824IVS+3del4, and 1824IVS+3insCT, are the cause of the aberrant splicing of the PCCA pre-mRNA and result in an in-frame deletion
of 54 nucleotides in the cDNA, probably leading to an unstable protein structure which is responsible for the lack of activity
leading to PCC deficiency in these patients.
Received: 6 June 1997 / Accepted: 14 July 1997 相似文献
149.
Belén Román Ana Ma Torres Diego Rubiales Jose Ignacio Cubero Zlatko Satovic 《Génome》2002,45(6):1057-1063
Orobanche crenata Forsk. is a root parasite that produces devastating effects on many crop legumes and has become a limiting factor for faba bean production in the Mediterranean region. The efficacy of available control methods is minimal and breeding for broomrape resistance remains the most promising method of control. Resistance seems to be scarce and complex in nature, being a quantitative characteristic difficult to manage in breeding programmes. To identify and map the QTLs (quantitative trait loci) controlling the trait, 196 F2 plants derived from the cross between a susceptible and a resistant parent were analysed using isozymes, RAPD, seed protein genes, and microsatellites. F2-derived F3 lines were studied for broomrape resistance under field conditions. Of the 130 marker loci segregating in the F2 population, 121 could be mapped into 16 linkage groups. Simple interval mapping (SIM) and composite interval mapping (CIM) were performed using QTL Cartographer. Composite interval mapping using the maximum number of markers as cofactors was clearly the most efficient way to locate putative QTLs. Three QTLs for broomrape resistance were detected. One of the three QTLs explained more than 35% of the phenotypic variance, whereas the others accounted for 11.2 and 25.5%, respectively. This result suggests that broomrape resistance in faba bean can be considered a polygenic trait with major effects of a few single genes. 相似文献
150.
Jesús Arenas Ana Abel Sandra Sánchez Belén Alcalá María T Criado Carlos M Ferreirós 《International microbiology》2006,9(4):273-280
A47 kDa neisserial outer-membrane antigenic protein (P47) was purified to homogeneity and used to prepare polyclonal anti-P47 antisera. Protein P47 was identified by MALDI-TOF fingerprinting analysis as the hypothetical lipoprotein NMB0035. Two-dimensional diagonal SDS-PAGE results suggested that, contrary to previous findings, P47 is not strongly associated with other proteins in membrane complexes. Western blotting with the polyclonal monospecific serum showed that linear P47 epitopes were expressed in similar amounts in the 27 Neisseria meningitidis strains tested and, to a lesser extent, in commensal Neisseria, particularly N. lactamica. However, dot-blotting assays with the same serum demonstrated binding variability between meningococcal strains, indicating differences in surface accessibility or steric hindrance by other surface structures. Specific anti-P47 antibodies were bactericidal against the homologous strain but had variable activity against heterologous strains, consistent with the results from dot-blotting experiments. An in-depth study of P47 is necessary to evaluate its potential as a candidate for new vaccine designs. 相似文献