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91.
92.
Tatiana Visnevschi-Necrasov Miguel A. Faria Sara C. Cunha J. Harris Harald W. E. Meimberg Manuel A. C. Curto M. Graça Pereira M. Beatriz P. P. Oliveira Eugénia Nunes 《Plant Systematics and Evolution》2013,299(2):357-367
This study presents the results of the identification and quantification of 12 isoflavones (prunetin, irilone, pseudobaptigenin, glycitein, daidzin, genistin, daidzein, pratensein, puerarin, biochanin A, formononetin and genistein) in 23 species of Trifolium (T. arvense, T. pratense, T. ligusticum, T. striatum, T. lappaceum, T. angustifolium, T. hirtum, T. subterraneum, T. isthmocarpum, T. stellatum, T. mutabile, T. strictum, T. fragiferum, T. alexandrinum, T. tomentosum. T. nigrescens subsp. petrisavii, T. nigrescens, T. glomeratum, T. subterraneum subsp. brachycalycinum, T. cherleri, T. resupinatum, T. campestre and T. repens). Isoflavones were extracted by an MSPD method and analyzed with HPLC coupled with a diode-array detector. The evaluation of molecular phylogeny of the IFS gene and the relation with isoflavone content was also performed. Five species (T. subterraneum subsp. brachycalycinum, T. alexandrinum, T. pratense, T. subterraneum and T. lappaceum) were identified with high levels of biochanin A (431–83 mg/kg), formononetin (72–365 mg/kg) and genistein (9–509 mg/kg), which could be utilized as alternative sources for the nutraceutical industry. Genetic phylogeny for the IFS gene was found in the species studied, with 20 out of 23 species having been divided into two clades, while the remaining three were genetically distant. Based on our results, we confirm the direct correlation between IFS gene polymorphism and isoflavones content in species of Trifolium particularly noted for formononetin. Therefore, the IFS gene can be utilized for screening Trifolium genotypes for formononetin. The relation of the three isoflavones' contents and the molecular phylogeny of plants determined by the IFS sequences, as a screening marker for plants with high isoflavone contents in Trifolium species, are to the best of our knowledge described for the first time. 相似文献
93.
Influence of sorbitol on protein production and glycosylation and cell wall formation in Trichoderma reesei 总被引:1,自引:0,他引:1
Górka-Nieć W Perlińska-Lenart U Zembek P Palamarczyk G Kruszewska JS 《Fungal biology》2010,114(10):855-862
Sorbitol is often used at 1 mol/liter as an osmotic stabilizer for cultivation of fungi with a fragile cell wall phenotype. On the other hand, at this concentration sorbitol causes an osmotic stress in fungal cells resulting in intensive production of intracellular glycerol. The highly increased consumption of glucose for glycerol synthesis may lead to changes in processes requiring carbohydrate residues. This study provides new information on the consequences of osmotic stress to the cell wall composition, protein production and glycosylation, and cell morphology of Trichoderma reesei. We observed that high osmolarity conditions enhanced biomass production and strongly limited synthesis of cell wall glucans and chitin. Moreover, in these conditions the amount of secreted protein decreased nearly ten-fold and expression of cbh1 and cbh2 genes coding for cellobiohydrolase I and cellobiohydrolase II, the main secretory proteins in T. reesei, was inhibited resulting in a lack of the proteins in the cell and cultivation medium. The activity of DPM synthase, enzyme engaged in both N- and O-glycosylation pathways, was reduced two-fold, suggesting an overall inhibition of protein glycosylation. However, the two modes of glycosylation were affected divergently: O-glycosylation of secreted proteins decreased in the early stages of growth while N-glycosylation significantly increased in the stationary phase. 相似文献
94.
95.
Alex Graça Contato Vanessa Kaplum Débora Botura Scariot Francielle Pelegrin Garcia Hugo Falzirolli Fábio Vandresen Tânia Ueda-Nakamura Sueli de Oliveira Silva Cleuza Conceição da Silva Celso Vataru Nakamura 《化学与生物多样性》2023,20(7):e202300523
Leishmaniasis is a tropical zoonotic disease. It is found in 98 countries, with an estimated 1.3 million people being affected annually. During the life cycle, the Leishmania parasite alternates between promastigote and amastigote forms. The first line treatment for leishmaniasis are the pentavalent antimonials, such as N-methylglucamine antimoniate (Glucantime®) and sodium stibogluconate (Pentostam®). These drugs are commonly related to be associated with dangerous side effects such as cardiotoxicity, nephrotoxicity, hepatotoxicity, and pancreatitis. Considering these aspects, this work aimed to obtain a new series of limonene-acylthiosemicarbazides hybrids as an alternative for the treatment of leishmaniasis. For this, promastigotes, axenic amastigotes, and intracellular amastigotes of Leishmania amazonensis were used in the antiproliferative assay; J774-A1 macrophages for the cytotoxicity assay; and electron microscopy techniques were performed to analyze the morphology and ultrastructure of parasites. ATZ−S-04 compound showed the best result in both tests. Its IC50, in promastigotes, axenic amastigotes and intracellular amastigotes was 0.35±0.08 μM, 0.49±0.06 μM, and 15.90±2.88 μM, respectively. Cytotoxicity assay determined a CC50 of 16.10±1.76 μM for the same compound. By electron microscopy, it was observed that ATZ−S-04 affected mainly the Golgi complex, in addition to morphological changes in promastigote forms of L. amazonensis. 相似文献
96.
97.
José Carlos Gonçalves Graça Diogo Maria Teresa Coelho Nieves Vidal Sara Amâncio 《In vitro cellular & developmental biology. Plant》2008,44(5):412-418
Endogenous levels of indole-3-acetic acid (IAA), indole-3-acetylaspartic acid (IAAsp) and indole-3-butyric acid (IBA) were
measured during the first 8 d of in vitro rooting of rootstock from the chestnut ‘M3’ hybrid by high performance liquid chromatography (HPLC). Rooting was induced
either by dipping the basal ends of the shoots into a 4.92-mM IBA solution for 1 min or by sub-culturing the shoots on solid
rooting medium supplemented with 14.8-μM IBA for 5 d. For root development, the induced shoots were transferred to auxin-free
solid medium. Auxins were measured in the apical and basal parts of the shoots by means of HPLC. Endogenous levels of IAA
and IAAsp were found to be greater in IBA-treated shoots than in control shoots. In extracts of the basal parts of the shoots,
the concentration of free IAA showed a significant peak 2 d after either root inductive method and a subsequent gradual decrease
for the remainder of the time course. The concentration of IAAsp peaked at day 6 in extracts of the basal parts of shoots
induced with 14.8-μM IBA for 5 d, whereas shoots induced by dipping showed an initial increase until day 2 and then remained
stable. In extracts from basal shoot portions induced by dipping, IBA concentration showed a transient peak at day 1 and a
plateau between day 2 and 4, in contrast to the profile of shoots induced on auxin-containing medium, which showed a significant
reduction between 4 and 6 d after transferred to auxin-free medium. All quantified auxins remained at a relatively low level,
virtually constant, in extracts from apical shoot portions, as well as in extracts from control non-rooting shoots. In conclusion,
the natural auxin IAA is the signal responsible for root induction, although it is driven by exogenous IBA independently of
the adding conditions. 相似文献
98.
Macedo ML das Graças Machado Freire M Novello JC Marangoni S 《Biochimica et biophysica acta》2002,1571(2):83-88
Bruchid larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil and the Mexican bean weevil, are pests that damage stored seeds. Plant lectins have been implicated as antibiosis factors against insects, particularly the cowpea weevil, Callosobruchus maculatus. Talisia esculenta lectin (TEL) was tested for anti-insect activity against C. maculatus and Zabrotes subfasciatus larvae. TEL produced ca. 90% mortality to these bruchids when incorporated in an artificial diet at a level of 2% (w/w). The LD(50) and ED(50) for TEL was ca. 1% (w/w) for both insects. TEL was not digested by midgut preparations of C. maculatus and Z. subfasciatus. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. 相似文献
99.
Patricia Messenberg Guimarães Ana Cristina Miranda Brasileiro Karina Proite Ana Claudia Guerra de Araújo Soraya Cristina Macedo Leal-Bertioli Aline Pic-Taylor Felipe Rodrigues da Silva Carolina Vianna Morgante Simone da Graça Ribeiro David John Bertioli 《Tropical plant biology》2010,3(4):183-192
Peanut (Arachis hypogaea) is amongst the most important legume crops in the world. One of its main yield constraints is the root-knot nematode Meloidogyne arenaria. A number of wild Arachis species, including A. stenosperma, are resistant to nematodes, and are a potential source of new resistance alleles for cultivated peanut. Using in silico subtraction of ESTs and macroarray analysis, we identified genes differentially expressed in A. stenosperma roots during its resistance response to M. arenaria. The three most differentially expressed genes [Auxin Repressed Protein (AsARP), Cytokinin Oxidase (AsCKX) and Metallothionein Type 2 (AsMET2)] were further analyzed using northern-blot and showed distinct expression profiles in the resistant A. stenosperma and susceptible A. hypogaea, both after, and sometimes even before, challenge with nematodes. Of the three most differentially expressed genes, AsARP and AsCKX are potentially involved in plant hormonal balance, and AsMET2 may be related to the reactive oxygen reaction triggered by the hypersensitive response (HR). 相似文献
100.
Potyviruses replicate and express their genomes in the cytoplasm in closely related membranous structures such as the endoplasmic reticulum or in the vicinity of the ER. The present research demonstrates the participation of plant cell organelles based on ultrastructural examination of compatible and incompatible interactions in tobacco- and potato-potato virus Y (PVY) necrotic strains. In two interaction types, PVYN Wi and PVYNTN particles were documented inside cell nuclei. Virus cytoplasmic inclusions and particles were associated with nuclear envelope pore complexes. Moreover, the PVY capsid protein was immunolocalised in the cell nucleus and nucleolus. Our results for the first time show PVY particles and capsid proteins inside the mitochondrion in compatible interactions, whereas in hypersensitive responses these interactions were identified inside chloroplasts. The PVY particles attached to mitochondria caused association groups of these organelles. The ultrastructural analysis clearly demonstrated both the dynamics of the endoplasmatic reticulum in two types of PVY interactions and connections between PVY cytoplasmic inclusions and particles with its membranous structures. Moreover, we demonstrated strongly localised immunodetection of the PVY capsid protein on the surface and in the vicinity of ER in cases of hypersensitive response as well as in compatible interaction. 相似文献