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91.
Drumo R Widmer G Morrison LJ Tait A Grelloni V D'Avino N Pozio E Cacciò SM 《Applied and environmental microbiology》2012,78(10):3523-3529
Recent studies have revealed extensive genetic variation among isolates of Cryptosporidium parvum, an Apicomplexan parasite that causes gastroenteritis in both humans and animals worldwide. The parasite's population structure is influenced by the intensity of transmission, the host-parasite interaction, and husbandry practices. As a result, C. parvum populations can be panmictic, clonal, or even epidemic on both a local scale and a larger geographical scale. To extend the study of C. parvum populations to an unexplored region, 173 isolates of C. parvum collected in Italy from humans and livestock (calf, sheep, and goat) over a 10-year period were genotyped using a multilocus scheme based on 7 mini- and microsatellite loci. In agreement with other studies, extensive polymorphism was observed, with 102 distinct multilocus genotypes (MLGs) identified among 173 isolates. The presence of linkage disequilibrium, the confinement of MLGs to individual farms, and the relationship of many MLGs inferred using network analysis (eBURST) suggest a predominantly clonal population structure, but there is also evidence that part of the diversity can be explained by genetic exchange. MLGs from goats were found to differ from bovine and sheep MLGs, supporting the existence of C. parvum subpopulations. Finally, MLGs from isolates collected between 1997 and 1999 were also identified as a distinct subgroup in principal-component analysis and eBURST analysis, suggesting a continuous introduction of novel genotypes in the parasite population. 相似文献
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Michelini L Meggio F La Rocca N Ferro S Ghisi R 《International journal of phytoremediation》2012,14(4):388-402
The application of manure to fertilize arable lands is one of the major means through which veterinary sulfonamides (SAs) enter the environment. Little is known about the capacity of woody plants to phytoremediate this class of antibiotics. To this purpose we performed preliminary studies to evaluate Salix fragilis L. response to sulfadimethoxine (SDM) by investigating both its ability to absorb and tolerate doses of SDM found in fresh faeces of treated calves. Forty cuttings were exposed to either 0, 0.5, 1, or 2 mM of SDM for one month. Decreases in photosynthetic electron transport rate and net CO2 assimilation after 25 days for the higher SDM concentrations were noticed. Moreover, alterations in root morphology of treated plants were observed and further investigated through electron microscopy. However, collected data revealed high root accumulation potential. These preliminary results are promising as they demonstrate that Salix fragilis L. can both absorb and tolerate high concentrations of SAs. 相似文献
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DM Iglesias R El-Kares A Taranta F Bellomo F Emma M Besouw E Levtchenko J Toelen L van den Heuvel L Chu J Zhao YK Young N Eliopoulos P Goodyer 《PloS one》2012,7(8):e42840
Cystinosis is a rare disease caused by homozygous mutations of the CTNS gene, encoding a cystine efflux channel in the lysosomal membrane. In Ctns knockout mice, the pathologic intralysosomal accumulation of cystine that drives progressive organ damage can be reversed by infusion of wildtype bone marrow-derived stem cells, but the mechanism involved is unclear since the exogeneous stem cells are rarely integrated into renal tubules. Here we show that human mesenchymal stem cells, from amniotic fluid or bone marrow, reduce pathologic cystine accumulation in co-cultured CTNS mutant fibroblasts or proximal tubular cells from cystinosis patients. This paracrine effect is associated with release into the culture medium of stem cell microvesicles (100-400 nm diameter) containing wildtype cystinosin protein and CTNS mRNA. Isolated stem cell microvesicles reduce target cell cystine accumulation in a dose-dependent, Annexin V-sensitive manner. Microvesicles from stem cells expressing CTNS(Red) transfer tagged CTNS protein to the lysosome/endosome compartment of cystinotic fibroblasts. Our observations suggest that exogenous stem cells may reprogram the biology of mutant tissues by direct microvesicle transfer of membrane-associated wildtype molecules. 相似文献
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Anand Raj Kumar Kullan Maria M. van Dyk Nicoletta Jones Arnulf Kanzler Arlene Bayley Alexander A. Myburg 《Tree Genetics & Genomes》2012,8(1):163-175
Traits that differentiate cross-fertile plant species can be dissected by genetic linkage analysis in interspecific hybrids.
Such studies have been greatly facilitated in Eucalyptus tree species by the recent development of Diversity Arrays Technology (DArT) markers. DArT is an affordable, high-throughput
marker technology for the construction of high-density genetic linkage maps. Eucalyptus grandis and Eucalyptus urophylla are commonly used to produce fast-growing, disease tolerant hybrids for clonal eucalypt plantations in tropical and subtropical
regions. We analysed 7,680 DArT markers in an F2 pseudo-backcross mapping pedigree based on an F1 hybrid clone of E. grandis and E. urophylla. A total of 2,440 markers (31.7%) were polymorphic and could be placed in linkage maps of the F1 hybrid and two pure-species
backcross parents. An integrated genetic linkage map was constructed for the pedigree resulting in 11 linkage groups (n = 11) with 2,290 high-confidence (LOD ≥ 3.0) markers and a total map length of 1,107.6 cM. DNA sequence analysis of the mapped
DArT marker fragments revealed that 43% were located in protein coding regions and 90% could be placed in the recently completed
draft genome assembly of E. grandis. Together with the anchored genomic sequence information, this linkage map will allow detailed genetic dissection of quantitative
traits and hybrid fitness characters segregating in the F2 progeny and will facilitate the development of markers for molecular
breeding in Eucalyptus. 相似文献
100.
Raffaella Ponassi Barbara Biasotti Valeria Tomati Silvia Bruno Alessandro Poggi Davide Malacarne Guido Cimoli Annalisa Salis Sarah Pozzi Maurizio Miglino Gianluca Damonte Pietro Cozzini Francesca Spyrakis Barbara Campanini Luca Bagnasco Nicoletta Castagnino Lorenzo Tortolina Anna Mumot Francesco Frassoni Antonio Daga Michele Cilli Federica Piccardi Ilaria Monfardini Miriam Perugini Gabriele Zoppoli Cristina D’Arrigo Raffaele Pesenti Silvio Parodi 《Cell cycle (Georgetown, Tex.)》2012,11(19):3703