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排序方式: 共有684条查询结果,搜索用时 31 毫秒
91.
The design of a thymus-dependent synthetic vaccine that will provide a universal T cell epitope for B cell epitopes is described in this study. Simultaneous incorporation into liposomes of both a peptide recognized by Th lymphocytes and a lipophilic hapten and the IgG antibody responses to this hapten were assessed in outbred mice. DNP-aminocaproyl phosphatidylethanolamine (DNP-CapPE) is a well characterized T-independent hapten Ag. HA2 peptide derived from the hemagglutinin protein of influenza virus contains amino acid sequences recognized by Th and T cytotoxic lymphocytes. In addition, HA2 contains a sequence of hydrophobic amino acids near the carboxyl terminus, allowing its incorporation into liposomes. Results of immunization show that (i), when DNP-CapPE is carried by liposomes without the HA2 peptide, an IgM antibody response is induced, (ii) liposomes carrying both HA2 and DNP-CapPE elicit an IgG antibody response to DNP in a dose-dependent fashion for both HA2 and DNP, (iii) the liposomes must be processed intracellularly in order to elicit a response, (iv) the system leads to a memory response for DNP, and (v) all of the IgG subclasses are elicited. These data suggest that liposomes containing the HA2 peptide exhibit a T-dependent carrier effect for a T-independent Ag. The significance of these findings is discussed in conjunction with the characteristics of the liposome model used. 相似文献
92.
Gonzalez-Zapata Fanny L Gómez-Osorio Sebastián Sánchez Juan Armando 《Coral reefs (Online)》2018,37(3):705-709
Coral Reefs - Understanding how corals and their symbionts specialize across depth gradients allows us to understand biodiversity in shallow and mesophotic coral ecosystems. Here we determined the... 相似文献
93.
Genome‐wide evidence for divergent selection between populations of a major agricultural pathogen
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The genetic and environmental homogeneity in agricultural ecosystems is thought to impose strong and uniform selection pressures. However, the impact of this selection on plant pathogen genomes remains largely unknown. We aimed to identify the proportion of the genome and the specific gene functions under positive selection in populations of the fungal wheat pathogen Zymoseptoria tritici. First, we performed genome scans in four field populations that were sampled from different continents and on distinct wheat cultivars to test which genomic regions are under recent selection. Based on extended haplotype homozygosity and composite likelihood ratio tests, we identified 384 and 81 selective sweeps affecting 4% and 0.5% of the 35 Mb core genome, respectively. We found differences both in the number and the position of selective sweeps across the genome between populations. Using a XtX‐based outlier detection approach, we identified 51 extremely divergent genomic regions between the allopatric populations, suggesting that divergent selection led to locally adapted pathogen populations. We performed an outlier detection analysis between two sympatric populations infecting two different wheat cultivars to identify evidence for host‐driven selection. Selective sweep regions harboured genes that are likely to play a role in successfully establishing host infections. We also identified secondary metabolite gene clusters and an enrichment in genes encoding transporter and protein localization functions. The latter gene functions mediate responses to environmental stress, including interactions with the host. The distinct gene functions under selection indicate that both local host genotypes and abiotic factors contributed to local adaptation. 相似文献
94.
Morgane Sonia Thion Donovan Low Aymeric Silvin Jinmiao Chen Pauline Grisel Jonas Schulte-Schrepping Ronnie Blecher Thomas Ulas Paola Squarzoni Guillaume Hoeffel Fanny Coulpier Eleni Siopi Friederike Sophie David Claus Scholz Foo Shihui Josephine Lum Arlaine Anne Amoyo Anis Larbi Sonia Garel 《Cell》2018,172(3):500-516.e16
95.
Mary H Torres Luz M Salazar Magnolia Vanegas Fanny Guzman Raul Rodriguez Yolanda Silva Jaiver Rosas Manuel E Patarroyo 《European journal of biochemistry》2003,270(19):3946-3952
The merozoite surface protein-1 represents a prime candidate for development of a malaria vaccine. Merozoite surface protein-1 has been shown to demonstrate high-activity peptide binding to human red blood cells. One of the high-activity binding peptides, named 5501, located in the N-terminus (amino acid sequence MLNISQHQCVKKQCPQNS) of the 19-kDa molecular mass fragment of merozoite surface protein-1, is conserved, nonimmunogenic and nonprotective. Its critical binding residues were identified and replaced with amino acids of similar mass but different charge, in order to modify their immunogenic and protective characteristics. Three analogues with positive or negative immunological results were studied by nuclear magnetic resonance to correlate their three-dimensional structure with their biological functions. The studied peptides presented alpha-helical fragments, but in different peptide regions and extensions, except for randomly structured 5501. We show that altering a few amino acids induced immunogenicity and protectivity against experimental malaria and changed the peptide three-dimensional structure, suggesting a better fit with immune-system molecules. 相似文献
96.
Fanny Mira-Moser 《Cell and tissue research》1972,125(1):88-107
Résumé Cinq types de cellules granulées se différencient au cours de la métamorphose dans la pars distalis de l'hypophyse du têtard de Crapaud.A la prémétamorphose apparaissent les deux types de cellules protidiques, les cellules glycoprotidiques de type II et des cellules glycoprotidiques d'un type intermédiaire. Cette dernière catégorie cellulaire disparaît au climax.A la prométamorphose se différencient les cellules glycoprotidiques de type IV.Au climax s'observent les cellules glycoprotidiques de type III.Les cellules glycoprotidiques de type II sont vraisemblablement responsables de la sécrétion de l'hormone thyréotrope (TSH). Il n'est pas encore possible de préciser la fonction des autres types cellulaires.Des fibres nerveuses ont pu être observées dans la pars distalis entre les cellules granulées.
The ultrastructure of the adenohypophysis in the toad, Bufo bufo L.III. Cell differentiation in the pars distalis during larval growth
Summary Five granulated cell types can be distinguished in the Toad's pars distalis during larval growth.During premetamorphosis the two types of protidic cells appear, the glycoprotein containing cells of type II and an intermediary cell type which disappears during the climax.During prometamorphosis the glycoprotein cells of type IV are apparent.During the climax the glycoprotein cells of type III can be observed.The glycoprotein containing cells of type II probably produce the thyroid-stimulating-hormone (TSH). The function of the other cell types can not be specified for the moment.Nervous fibers have been observed in the pars distalis between granulated cells.
Tous nos remerciements vont à Mme Sidler-Ansermet photographe, Mlle Schorderet secrétaire, et Mlle Schutz technicienne, de l'aide qu'elles ont apportée à la réalisation de ce mémoire. 相似文献
97.
98.
Rational design of a monomeric and photostable far‐red fluorescent protein for fluorescence imaging in vivo
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William Clay Gustafson Rubén Ruiz‐González Luca Signor Fanny Marzocca Franck Borel Matthew P. Klassen Kalpana Makhijani Antoine Royant Yuh‐Nung Jan William A. Weiss Su Guo Xiaokun Shu 《Protein science : a publication of the Protein Society》2016,25(2):308-315
Fluorescent proteins (FPs) are powerful tools for cell and molecular biology. Here based on structural analysis, a blue‐shifted mutant of a recently engineered monomeric infrared fluorescent protein (mIFP) has been rationally designed. This variant, named iBlueberry, bears a single mutation that shifts both excitation and emission spectra by approximately 40 nm. Furthermore, iBlueberry is four times more photostable than mIFP, rendering it more advantageous for imaging protein dynamics. By tagging iBlueberry to centrin, it has been demonstrated that the fusion protein labels the centrosome in the developing zebrafish embryo. Together with GFP‐labeled nucleus and tdTomato‐labeled plasma membrane, time‐lapse imaging to visualize the dynamics of centrosomes in radial glia neural progenitors in the intact zebrafish brain has been demonstrated. It is further shown that iBlueberry can be used together with mIFP in two‐color protein labeling in living cells and in two‐color tumor labeling in mice. 相似文献
99.
Ingrid C. A. Boucaud Pénélope A. Valère Mélissa L. N. Aguirre Smith Blandine Doligez Laure Cauchard Fanny Rybak Clémentine Vignal 《Ibis》2016,158(3):630-644
Although most bird species show monogamous pair bonds and bi‐parental care, little is known of how mated birds coordinate their activities. Whether or not partners communicate with each other to adjust their behaviour remains an open question. During incubation and the first days after hatching, one parent – generally the female – stays in the nest for extended periods, and might depend on acoustic communication to exchange information with its mate outside. The Great Tit Parus major is an interesting study system to investigate intra‐pair communication at the nest because males address songs to their mate while she is in the nest cavity, and females answer the male from the cavity with calls. However, the function of this communication remains unknown. In this study, we recorded the vocalizations and observed the resulting behaviour of Great Tit pairs around the nest at different breeding stages (laying, incubation and chick‐rearing). We observed vocal exchanges (vocalization bouts, alternated on the same tempo, between the female inside the nest and her male outside) in three contexts with different outcomes: (1) the female left the nest, (2) the male entered the box with food, and the female then used specific call types, (3) mates stopped calling but did not leave or enter the nest. The structure of vocal exchanges was globally stable between contexts, but females used calls with an up‐shifted spectrum during exchanges, at the end of which they left the nest or the male entered the nest. Birds vocalized more and at higher tempo during exchanges that ended up in feeding inside the nest. Birds also vocalized more during exchanges taking place during laying – a period of active mate guarding – than during incubation. We conclude that vocal exchanges could signal the females’ need for food and the males’ mate guarding behaviour, and discuss other possible functions of this communication. 相似文献
100.