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991.
Immunostaining for nucleophosmin in bone marrow trephine biopsy specimens in acute myeloid leukemias
992.
Bouke C. de Jong Ifedayo Adetifa Brigitte Walther Philip C. Hill Martin Antonio Martin Ota & Richard A. Adegbola 《FEMS immunology and medical microbiology》2010,58(1):102-105
Mycobacterium africanum (MAF) is a common cause of human pulmonary tuberculosis in West Africa. We previously described phenotypic differences between MAF and Mycobacterium tuberculosis (MTB) among 290 patients. In the present analysis, we compared 692 tuberculosis patients infected with the two most common lineages within the (MTB) complex found in the Gambia, namely MAF West African type 2 (39% prevalence) and Euro-American MTB (55% prevalence). We identified additional phenotypic differences between infections with these two organisms. MAF patients were more likely to be older and HIV infected. In addition, they had worse disease on chest X-ray, despite complaining of cough for an equal duration, and were more likely severely malnourished. In this cohort, the prevalence of MAF did not change significantly over a 7-year period. 相似文献
993.
Laura Tomassoli Antonio Tiberini Massimiliano Meneghini 《Journal of Phytopathology》2010,158(4):314-316
Since 2006, winter melon plants (Cucumis melo L. var inodorus) showing symptoms of pin‐point yellow spots were noticed in Sicily (Italy). Leaf samples were tested by enzyme‐linked immunosorbent assay to the most important viruses‐infecting cucurbits. Zucchini yellow fleck virus (ZYFV, genus Potyvirus) was the only virus detected. Surveys in 2007 and 2008 revealed an increasing number of sites in Sicily with ZYFV‐infected winter melon plants. To confirm the identity of the virus as ZYFV, two isolates from different locations were sequenced and shown to be approximately 85% identical to the published sequences of isolates previously identified in Italy and France. This is the first report of ZYFV occurring on melon in Italy. 相似文献
994.
A. Trabocchi G. Menchi E. Danieli D. Potenza N. Cini A. Bottoncetti S. Raspanti A. Pupi Antonio Guarna 《Amino acids》2010,38(1):329-337
3-Aza-6,8-dioxabicyclo[3.2.1]octane-based amino acids as reverse turn inducers have been introduced into cyclic peptidomimetics
containing the RGD or DGR retro-sequence, in order to achieve a stereochemical scanning of the binding capability of the resulting
molecules towards αvβ3 and αvβ5 integrins, resulting in retro-inverso DGR peptides as micromolar ligands. A comparative analysis between the conformational
preferences of 4 and of its isomer 3, having the opposite RGD sequence, was reported with respect to the binding activity, giving insight into the factors affecting
the preferential binding of 4 to the αvβ5 integrin. 相似文献
995.
Benedetta Gualeni Marcella Facchini Fabio De Leonardis Ruggero Tenni Giuseppe Cetta Manuela Viola Alberto Passi Andrea Superti-Furga Antonella Forlino Antonio Rossi 《Matrix biology》2010,29(6):453-460
Mutations in the sulfate transporter gene, SCL26A2, lead to cartilage proteoglycan undersulfation resulting in chondrodysplasia in humans; the phenotype is mirrored in the diastrophic dysplasia (dtd) mouse. It remains unclear whether bone shortening and deformities are caused solely by changes in the cartilage matrix, or whether chondroitin sulfate proteoglycan undersulfation affects also signalling pathways involved in cell proliferation and differentiation. Therefore we studied macromolecular sulfation in the different zones of the dtd mouse growth plate and these data were related to growth plate histomorphometry and proliferation analysis.A 2-fold increase of non-sulfated disaccharide in dtd animals compared to wild-type littermates in the resting, proliferative and hypertrophic zones was detected indicating proteoglycan undersulfation; among the three zones the highest level of undersulfation was in the resting zone. The relative height of the hypertrophic zone and the average number of cells per column in the proliferative and hypertrophic zones were significantly reduced compared to wild-types; however the total height of the growth plate was within normal values. The chondrocyte proliferation rate, measured by bromodeoxyuridine labelling, was also significantly reduced in mutant mice. Immunohistochemistry combined with expression data of the dtd growth plate demonstrated that the sulfation defect alters the distribution pattern, but not expression, of Indian hedgehog, a long range morphogen required for chondrocyte proliferation and differentiation.These data suggest that in dtd mice proteoglycan undersulfation causes reduced chondrocyte proliferation in the proliferative zone via the Indian hedgehog pathway, therefore contributing to reduced long bone growth. 相似文献
996.
Shailesh Sharma Gabriele Cavallaro Antonio Rosato 《Journal of biological inorganic chemistry》2010,15(4):559-571
Multiheme c-type cytochromes (MHCs) are metalloproteins that can play various biochemical roles, including enzymatic activity and electron
transfer. As electron transfer proteins, the presence of multiple heme cofactors in the vicinity allows electrons to rapidly
travel relatively long distances. MHCs are often characterized by relatively low structural complexity, with the heme cofactors
being largely responsible for maintaining the structure in place, owing to the protein–heme covalent linkages. In this work,
we analyzed an extensive ensemble of 594 complete prokaryotic proteomes, amounting to more than 1.9 million sequences, to
characterize their content in MHCs. We identified 1,659 MHCs in 258 organisms. The presence of MHCs was found to correlate
quite well with the capability of an organism to synthesize or take up heme. For two organisms, the presence of MHCs in the
proteome could be taken as a hint to the presence of divergent heme uptake pathways. The most common numbers of heme-binding
motifs in a sequence were four (25%) and two (23%), followed by five (13%) and ten (9.8%). The average protein-to-heme ratio
was relatively similar for all MHCs, except diheme proteins, regardless of the number of motifs at around 60 ± 30. The latter
ratio could in favorable cases be a useful indicator for functional assignments of novel MHCs. Finally, we showed that the
amount of structural information currently available for MHCs is limited with respect to the diversity of this broad class
of metalloproteins. Experimental efforts in the structural investigation of MHCs are thus warranted. 相似文献
997.
Daniel Gómez Patricia Lucas‐Elío Francisco Solano Antonio Sanchez‐Amat 《Molecular microbiology》2010,75(2):462-473
The melanogenic marine bacterium Marinomonas mediterranea synthesizes a novel antimicrobial protein (LodA) with lysine‐epsilon oxidase activity (EC 1.4.3.20). Homologues to LodA have been detected in several Gram‐negative bacteria, where they are involved in biofilm development. Adjacent to lodA is located a second gene, lodB, of unknown function. This genomic organization is maintained in all the microorganisms containing homologues to these genes. In this work we show that lodA and lodB constitute an operon. Western blot analysis and enzymatic determinations revealed that LodA is secreted to the external medium when the culture reaches the stationary phase. LodB, on the other hand, has only been detected inside cells, but it is not secreted. The expression of the lysine‐epsilon oxidase (LOD) activity in M. mediterranea requires functional copies of both genes since mutants lacking either lodA or lodB do not show any LOD activity. The active form of LodA containing the quinonic cofactor is intracellularly generated in a process that takes place only in the presence of LodB, suggesting that the latter is involved in this process. Moreover, in the absence of one of the proteins, the stability of the partner protein is compromised leading to a marked decrease in its cellular levels. 相似文献
998.
Iñigo Zuberogoitia Jose Antonio González-Oreja Jabi Zabala Cristina Rodríguez-Refojos 《Biodiversity and Conservation》2010,19(5):1455-1469
Biological invasions are an important cause of biodiversity loss, American mink being one of the worst invasive species in
Europe. We performed a 13-week control program of the species in the Butron river system (Northern Spain), where a natural
population of the European mink is found. Three population estimates were considered: an absolute minimum, an intermediate
scenario and a pessimistic one (n = 35, 49 and 70 animals, respectively). After 2,242 cage trap-nights, trapping success varied from 44 to 89% of these estimates.
In addition, we evaluated the costs of eradicating the estimated populations; costs ranged between 652.5 and 2,970 € per mink,
and would rise up to 83,462 € for the intermediate estimate under an exponential function linking captures and costs, or ca. 172.500 € to capture the highest estimate under a log-function. The implications of these numbers for the design and implementation
of future control projects are discussed. 相似文献
999.
ZmMYB31 directly represses maize lignin genes and redirects the phenylpropanoid metabolic flux 总被引:4,自引:0,他引:4
Fornalé S Shi X Chai C Encina A Irar S Capellades M Fuguet E Torres JL Rovira P Puigdomènech P Rigau J Grotewold E Gray J Caparrós-Ruiz D 《The Plant journal : for cell and molecular biology》2010,64(4):633-644
Few regulators of phenylpropanoids have been identified in monocots having potential as biofuel crops. Here we demonstrate the role of the maize (Zea mays) R2R3-MYB factor ZmMYB31 in the control of the phenylpropanoid pathway. We determined its in vitro consensus DNA-binding sequence as ACC(T)/(A) ACC, and chromatin immunoprecipitation (ChIP) established that it interacts with two lignin gene promoters in vivo. To explore the potential of ZmMYB31 as a regulator of phenylpropanoids in other plants, its role in the regulation of the phenylpropanoid pathway was further investigated in Arabidopsis thaliana. ZmMYB31 downregulates several genes involved in the synthesis of monolignols and transgenic plants are dwarf and show a significantly reduced lignin content with unaltered polymer composition. We demonstrate that these changes increase cell wall degradability of the transgenic plants. In addition, ZmMYB31 represses the synthesis of sinapoylmalate, resulting in plants that are more sensitive to UV irradiation, and induces several stress-related proteins. Our results suggest that, as an indirect effect of repression of lignin biosynthesis, transgenic plants redirect carbon flux towards the biosynthesis of anthocyanins. Thus, ZmMYB31 can be considered a good candidate for the manipulation of lignin biosynthesis in biotechnological applications. 相似文献
1000.
Gary Tresadern Jose María Cid Gregor J. Macdonald Juan Antonio Vega Ana Isabel de Lucas Aránzazu García Encarnación Matesanz María Lourdes Linares Daniel Oehlrich Hilde Lavreysen Ilse Biesmans Andrés A. Trabanco 《Bioorganic & medicinal chemistry letters》2010,20(1):175-179
Imidazo[1,2-a]pyridines were identified via their shape and electrostatic similarity as novel positive allosteric modulators of the metabotropic glutamate 2 receptor. The subsequent synthesis and SAR are described. Potent, selective and metabolically stable compounds were found representing a promising avenue for current further studies. 相似文献