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51.
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Pathogenesis-related (PR) proteins from pepper (Capsicum annuum L.) cv. Americano (tolerant) and cv. Smith-5 (sensitive), both elicited by infection with cucumber mosaic virus (CMV), were assayed for chitinase and glucanase activities. Two basic PR-proteins, Mr 49.0 and 28.0 kD, were elicicited from the intracellular fraction (INTRA-F) of both cvs. by CMV infection, while four acidic Mr 15, 19, 36 and 40 kD and two basic Mr 21.2 and 24 kD PR-proteins were elicited from the intercellular fluid (IF) of cv. Americano leaves. Five acidic Mr 21.5, 23.2, 24.4, 25.2 and 36 kD and five basic Mr 23.3, 26, 28.8, 30 and 32.3 kD PR proteins were elicited from the IF of cv. Smith-5. Isoelectric focusing (IEF) of the IF and the INTRA-F proteins revealed the occurrence, in both pepper cultivars, of one acidic Mr 36 kD and one basic Mr 25 kD PR-protein with glucanase activity. After native-PAGE for acidic proteins, the acidic PR-protein of Rf 0.7 and Mr 36 kD present in the IF of both pepper cvs. showed glucanase activity. Native-PAGE for basic proteins of the INTRA-F showed the presence of one band (Rf 0.61, Mr 25 kD) common to both cvs. and two additional bands (Rf 0.49, Mr 26 kD and Rf 0.79, Mr 33 kD) in the cv. Americano with glucanase activity. The specificity shown by the basic PR-proteins suggests glucanase activity is involved in the mechanisms of resistance to CMV in the cv. Americano. There was no difference in chitinase isoform patterns between the two pepper cultivars analyzed. After IEF of the IF proteins, one acidic chitinase isoform was detected. Native-PAGE separation of the IF showed one band (Mr 30 kD) with chitinase activity. Chitinase activity was not detected in the INTRA-F of either cultivar. 相似文献
53.
Most extant New World marsupials belong in the Didelphidae, which comprises ca. 110 currently recognized species of opossums. Didelphids are small mammals with their mean body mass, at species level, ranging from ca. 7 g to 2.2 kg. The largest species belong in a single clade, while substantial variation remains scattered across the remaining groups. We seek out to explore the details of this mass variation in an evolutionary framework. To this end, we first reconstructed the phylogeny of didelphids based on an extensive, although fragmentary sample of sequences from ten genes. We recovered a fully resolved, highly robust phylogeny that tested and confirmed most previously reported groupings, providing a simultaneous depiction of phylogenetic relationships for 81 % of currently recognized species and all relevant supra-specific clades. As much as 69 % of total body mass variation in didelphids was explained by this phylogenetic hypothesis. Mapped on it, mass variation evolved as much as 6.8 kg of total changes, starting from a reconstructed ancestral body mass range of 22–33 g. No single, family-wide pattern was evident; in fact, the dominant pattern for mass variation was that of increases in body mass along a few successive branches, or phyletic giantism, followed by apomorphic nanism, i.e., decreases localized in single terminal branches. Phyletic trends indicated the persistence of gradual, directional changes along considerable spans of geological time and show that substantial variation of interest resides in this and perhaps most groups of small mammals. 相似文献
54.
Lisa Del Bel Belluz Riccardo Guidi Ioannis S. Pateras Laura Levi Boris Mihaljevic Syed Fazle Rouf Marie Wrande Marco Candela Silvia Turroni Claudia Nastasi Clarissa Consolandi Clelia Peano Toma Tebaldi Gabriella Viero Vassilis G. Gorgoulis Thorbj?rn Krejsgaard Mikael Rhen Teresa Frisan 《PLoS pathogens》2016,12(4)
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QUANTITATIVE AUTORADIOGRAPHIC STUDY OF LABELED RNA IN RABBIT OPTIC NERVE AFTER INTRAOCULAR INJECTION OF [3H]URIDINE 总被引:1,自引:1,他引:0
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Pierluigi Gambetti Lucila Autilio-Gambetti Brenda Shafer LaDorna Pfaff 《The Journal of cell biology》1973,59(3):677-684
The distribution of labeled RNA in the optic nerve of the rabbit was studied by quantitative ultrastructural autoradiography after the intraocular injection of [3H]uridine. The highest density of silver grains related to [3H]RNA (27–40 grains/100 µm2) was found in glial cell perikarya; a slightly lower density was present in the glial nuclei (19–20 grains/100 µm2). Axons (4–5 grains/100 µm2) and myelin (2–3 grains/100 µm2) had the lowest grain densities. 74–83% of all counted grains were located outside the axons. By comparing the grain density distribution over the axon with that expected in the case of an exclusive labeling of the surrounding myelin and glial cell processes, it was concluded that the axons contained a number of grains representing [3H]RNA significantly higher than that expected to scatter from myelin and glial processes. Most of these grains were concentrated at the periphery of the axon and were not related to axonal mitochondria. 相似文献
57.
Alkylating agents from sugars. Alkyl hexopyranoside derivatives as carrier systems for chlorambucil.
F Iglesias-Guerra J I Candela J Bautista F Alcudia J M Vega-Pérez 《Carbohydrate research》1999,316(1-4):71-84
Chlorambucil derivatives involving alkyl 2-aminodeoxy sugars have been synthesized in good yield by coupling the chlorambucil moiety to positions C-2 or C-3 of the sugar, directly or via a spacer. The starting material was easily available from 2-acetamido-2-deoxy-D-glucose. The final compounds were tested for cytotoxicity, and some of those that presented the best results were studied for inhibition of cell proliferation. 相似文献
58.
Eduardo Mateo-Bonmatí Rubén Casanova-Sáez Héctor Candela José Luis Micol 《Planta》2014,240(5):1113-1122
Map-based (positional) cloning has traditionally been the preferred strategy for identifying the causal genes underlying the phenotypes of mutants isolated in forward genetic screens. Massively parallel sequencing technologies are enabling the rapid cloning of genes identified in such screens. We have used a combination of linkage mapping and whole-genome re-sequencing to identify the causal mutations in four loss-of-function angulata (anu) mutants. These mutants were isolated in a screen for mutants with defects in leaf shape and leaf pigmentation. Our results show that the anu1-1, anu4-1, anu9-1 and anu12-1 mutants carry new alleles of the previously characterized SECA2, TRANSLOCON AT THE OUTER MEMBRANE OF CHLOROPLASTS 33 (TOC33), NON-INTRINSIC ABC PROTEIN 14 (NAP14) and CLP PROTEASE PROTEOLYTIC SUBUNIT 1 (CLPR1) genes. Re-sequencing the genomes of fine mapped mutants is a feasible approach that has allowed us to identify a moderate number of candidate mutations, including the one that causes the mutant phenotype, in a nonstandard genetic background. Our results indicate that anu mutations specifically affect plastid-localized proteins involved in diverse processes, such as the movement of peptides through chloroplast membranes (ANU1 and ANU4), metal homeostasis (ANU9) and protein degradation (ANU12). 相似文献
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Beatrice Vitali Maurice Ndagijimana Federica Cruciani Paola Carnevali Marco Candela Maria Elisabetta Guerzoni Patrizia Brigidi 《BMC microbiology》2010,10(1):4