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991.
Re MC Schiavone P Vitone F Bon I De Crignis E Biagetti C Alessandrini F Gibellini D 《The new microbiologica》2008,31(1):19-26
Standard serological tests (both EIA and Immunoblotting) have reached high levels of sensitivity and reproducibility, but do not indicate whether infection is recent or longstanding. Since many patients with HIV-1 infection are not usually diagnosed until symptom presentation, the possibility to distinguish between acute and chronic infection has become increasingly important for the purposes of therapeutic decision-making, partner notification and epidemiological surveillance. We evaluated a guanidine-based-antibody-avidity assay in a selected group of recent (within six months from seroconversion) and chronic (more than forty eight months) HIV-1 infections in an attempt to shed more light on the significance of the avidity index in establishing the time of infection. Sera from newly infected individuals showed a low mean avidity index (ranging from 0.35 to 0.60 with a standard deviation 0.09) at baseline and a clear increasing value at the following times of observation. Our data showed that an avidity index <0.70 might be presumptive of infection occurring within 9 months. Avidity index levels might distinguish between acute and chronic infection. The method is semi-automated, inexpensive and easy to perform, and estimates the time elapsed from seroconversion, thereby identifying a recent infection. 相似文献
992.
Non-organ-specific autoantibodies in renal transplant recipients: relation to BK virus infection 总被引:1,自引:0,他引:1
Costa C Touscoz GA Bergallo M Sidoti F Terlizzi ME Astegiano S Merlino C Segoloni GP Cavallo R 《The new microbiologica》2008,31(2):175-180
Polyomavirus BK reactivation is common in renal transplant recipients and may cause nephropathy with significant graft dysfunction. The induction of anti-double stranded DNA (anti-dsDNA) antibodies by BKV has been described in experimental animals and during primary infection, and has been implicated in the pathogenesis of systemic lupus erythematosus. This study evaluated the occurrence of anti-dsDNA antibodies and non-organ-specific autoantibodies (NOSA) by indirect immunofluorescence before transplantation and at 3 and 6 months post-transplantation in 90 renal transplant recipients and the association with BKV reactivation, demographic and clinical features. Moreover, the relation to HCMV infection, as detected by pp65-antigenemia, was also evaluated. Post-transplantation NOSAs were present in 23/90 (25.6%) and anti-dsDNA antibodies in 17/90 (18.9%). BK viremia was detected in at least one serum sample in 22 patients: 9 anti-dsDNA antibody-positive vs 13 negative (p<0.01). No significant correlation between the occurrence of NOSAs and anti-dsDNA antibodies and demographic and clinical features was found. No significant association with pp65-antigenemia-positivity was found, although antigenemia was positive in 6/23 NOSA-positive patients (26.1%). Although a relation seems to exist between BKV and the occurrence of anti-dsDNA antibodies in renal transplant patients, the lack of correlation with other epidemiological and clinical features does not allow any conclusion. The role of autoimmune response in this context and the relation with other patient-related factors and infectious agents should be further investigated. 相似文献
993.
Alessandro Chiarucci Marco Calderisi Francesca Casini Ilaria Bonini 《Folia Geobotanica》2008,43(1):19-33
The effects of the chemical and physical factors associated with geothermal activity on plant community structure and composition were investigated in one of the largest geothermal fields of central Italy. The study site was located in the geothermal area of Sasso Pisano – Monte Rotondo Marittimo, Southern Tuscany. The percentage cover of all vascular plant, bryophyte and lichen species was estimated within 119 circular plots of 0.25 m2. For each plot the soil pH, soil temperature, slope, aspect, incident radiation, soil nitrogen and carbon contents were also quantified. Two vascular plants, Calluna vulgaris and Agrostis castellana, were found to be the most widespread species tolerating the harshest conditions in terms of low soil pH and high soil temperature. The most widespread cryptogam species was Hypnum cupressiforme. Spatially autoregressive models showed that a proportion of about 41–51% of the variance in species richness of one group of plants (vascular or cryptogamic plants) could be modelled by using three or four uncorrelated environmental factors respectively (soil temperature, soil nitrogen and soil C/N ratio and these three plus incident radiation). For the total number of species (vascular and cryptogamic plants), the variance explained by the same three uncorrelated variables was about 57%. This study evidenced a strong environmental control of community composition and species richness, in a site subjected to extreme soil values of soil pH and temperature. The dominance of vascular over cryptogamic vegetation in this geothermal site can be explained by the combined effects of geothermal stress (low soil pH and high soil temperature) with the summer drought typical of the Mediterranean climate. 相似文献
994.
995.
Francesca Gherardi Sandro Bertolino Marco Bodon Sandra Casellato Simone Cianfanelli Marco Ferraguti Elisabetta Lori Graziella Mura Annamaria Nocita Nicoletta Riccardi Giampaolo Rossetti Emilia Rota Riccardo Scalera Sergio Zerunian Elena Tricarico 《Biological invasions》2008,10(4):435-454
The paper provides a list of the non-indigenous animal species occurring today in Italian inland waters. Xenodiversity was
found to amount to 112 species (64 invertebrates and 48 vertebrates), which contribute for about 2% to the inland-water fauna
in Italy. Northern and central regions are most affected, and Asia, North America, and the rest of Europe are the main donor
continents. The large majority of non-indigenous species entered Italy as a direct or indirect effect of human intervention.
A difference between invertebrates and vertebrates was found for their mode of arrival (unintentional for invertebrates and
intentional for vertebrates). Accidental transport, in association with both fish (for aquaculture or stock enhancement) and
crops, has been the main vector of invertebrate introductions, whereas vertebrates were mostly released for stocking purposes.
Overall stock enhancement (47.92%) and culture (37.5%) prevailed over the other pathways. Seventeen and 7 species of our list
are included among the 100 worst invasive species of Europe (DAISIE) and of the world (IUCN), respectively. For some (but
not all) non-indigenous species recorded in Italy the multilevel impact exerted on the recipient communities and ecosystems
is known, even if rarely quantified, but knowledge on their chronic impact is still missing. Additional research is needed
to provide criteria for prioritizing intervention against well established invaders and identify which new potential invader
should be targeted as “unwanted”. 相似文献
996.
Raciti D Reggiani L Geffers L Jiang Q Bacchion F Subrizi AE Clements D Tindal C Davidson DR Kaissling B Brändli AW 《Genome biology》2008,9(5):R84-21
Background
The pronephros, the simplest form of a vertebrate excretory organ, has recently become an important model of vertebrate kidney organogenesis. Here, we elucidated the nephron organization of the Xenopus pronephros and determined the similarities in segmentation with the metanephros, the adult kidney of mammals.Results
We performed large-scale gene expression mapping of terminal differentiation markers to identify gene expression patterns that define distinct domains of the pronephric kidney. We analyzed the expression of over 240 genes, which included members of the solute carrier, claudin, and aquaporin gene families, as well as selected ion channels. The obtained expression patterns were deposited in the searchable European Renal Genome Project Xenopus Gene Expression Database. We found that 112 genes exhibited highly regionalized expression patterns that were adequate to define the segmental organization of the pronephric nephron. Eight functionally distinct domains were discovered that shared significant analogies in gene expression with the mammalian metanephric nephron. We therefore propose a new nomenclature, which is in line with the mammalian one. The Xenopus pronephric nephron is composed of four basic domains: proximal tubule, intermediate tubule, distal tubule, and connecting tubule. Each tubule may be further subdivided into distinct segments. Finally, we also provide compelling evidence that the expression of key genes underlying inherited renal diseases in humans has been evolutionarily conserved down to the level of the pronephric kidney.Conclusion
The present study validates the Xenopus pronephros as a genuine model that may be used to elucidate the molecular basis of nephron segmentation and human renal disease. 相似文献997.
Hominoid chromosomal rearrangements on 17q map to complex regions of segmental duplication 总被引:1,自引:0,他引:1
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Cardone MF Jiang Z D'Addabbo P Archidiacono N Rocchi M Eichler EE Ventura M 《Genome biology》2008,9(2):R28
Background
Chromosomal rearrangements, such as translocations and inversions, are recurrent phenomena during evolution, and both of them are involved in reproductive isolation and speciation. To better understand the molecular basis of chromosome rearrangements and their part in karyotype evolution, we have investigated the history of human chromosome 17 by comparative fluorescence in situ hybridization (FISH) and sequence analysis. 相似文献998.
The autoimmune regulator PHD finger binds to non-methylated histone H3K4 to activate gene expression 总被引:2,自引:0,他引:2
Org T Chignola F Hetényi C Gaetani M Rebane A Liiv I Maran U Mollica L Bottomley MJ Musco G Peterson P 《EMBO reports》2008,9(4):370-376
Mutations in the gene autoimmune regulator (AIRE) cause autoimmune polyendocrinopathy candidiasis ectodermal dystrophy. AIRE is expressed in thymic medullary epithelial cells, where it promotes the expression of tissue-restricted antigens. By the combined use of biochemical and biophysical methods, we show that AIRE selectively interacts with histone H3 through its first plant homeodomain (PHD) finger (AIRE-PHD1) and preferentially binds to non-methylated H3K4 (H3K4me0). Accordingly, in vivo AIRE binds to and activates promoters containing low levels of H3K4me3 in human embryonic kidney 293 cells. We conclude that AIRE-PHD1 is an important member of a newly identified class of PHD fingers that specifically recognize H3K4me0, thus providing a new link between the status of histone modifications and the regulation of tissue-restricted antigen expression in thymus. 相似文献
999.
Stefanelli P Colotti G Neri A Salucci ML Miccoli R Di Leandro L Ippoliti R 《IUBMB life》2008,60(9):629-636
The present study evaluates sequence conservation in the gene coding for nitrite reductase (aniA) and AniA expression from a panel of Neisseria meningitidis isolates. Sequence analysis of the coding region in 19 disease-associated and 4 carrier strains notwithstanding a high degree of sequence similarity showed a number of nucleotide changes, some of which possibly resulted in premature translation termination or function loss. In particular, in one disease-associated strain a 9-residues insertion was found to be located close to the type I Cu-site and a catalytic histidine at position 280 was mutated into a leucine. In two strains from carriers, a sequence corresponding to a portion of a transposase gene within the aniA was also found. The AniA protein was always expressed, except for these two carriers strains and for other two strains in which the presence of the premature stop codons was recognized. The biochemical properties of the cloned soluble domain of the enzyme (sAniA) from N. meningitidis reference MC58 strain and from a clinical invasive isolate were studied. In particular, biochemical analysis of sAniA from MC58 demonstrated a clear dependence of its catalytic activity upon acidification, while the clinical isolate-derived sAniA was not functional. Thus, the results obtained suggest that the presence of a conserved and functional aniA gene is not essential for meningococcal survival. 相似文献
1000.
Beretta L Cossu M Marchini M Cappiello F Artoni A Motta G Scorza R 《Arthritis research & therapy》2008,10(5):R103-7