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21.
V. L. M. Pádua L. D. Fernandes D. E. de Oliveira E. Mansur 《In vitro cellular & developmental biology. Plant》1998,34(4):285-288
An efficient clonal propagation procedure for a Brazilianindica rice subspecies was developed with shoot apex explants. Shoot apices were excised from 4-d-old seedlings and cultured on
MS medium supplemented with 8.9 μM 6-benzyladenine. The efficiency of shoot production was influenced by growth regulators and light treatments to the donor
plant. Explants derived from seedlings growth in the presence of 10.7 μM naphthaleneacetic acid and in the absence of light showed significantly increased regeneration capacity as compared to control
explants. Anatomical analysis of the new shoot meristems revealed that they originated from preexisting apical and axillary
meristem as well as from the mesocotyl parenchyma. 相似文献
22.
In vitro regeneration from leaf explants of Neoregelia cruenta (R. Graham) L.B. Smith,an endemic bromeliad from Eastern Brazil 总被引:1,自引:0,他引:1
Carneiro L.A. Araújo R.F.G. Brito G.J.M. Fonseca M.H.P.B. Costa A. Crocomo O.J. Mansur E. 《Plant Cell, Tissue and Organ Culture》1998,55(2):79-83
An efficient plant regeneration system was developed for the induction of direct shoot formation from leaves derived from
seedlings of Neoregelia cruenta, an endemic Bromeliaceae of Eastern Brazil. Shoot differentiation occurred directly from the
leaf bases. In vitro responses were influenced by seedling age and growth regulator combinations. Highest regeneration rates
were obtained from explants excised from 7-week-old seedlings cultured in the presence of 22 μM BA and 2.5 μM NAA. Shoot conversion
to whole plants was most effective in shoots formed in response to 4.4 or 8.8 μM BA combined with 2.5 μM NAA.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
23.
Daniel Pereira Maria Cristina Dreher Mansur Leandro D. S. Duarte Arthur Schramm de Oliveira Daniel Mansur Pimpão Cláudia Tasso Callil Cristián Ituarte Esperanza Parada Santiago Peredo Gustavo Darrigran Fabrizio Scarabino Cristhian Clavijo Gladys Lara Igor Christo Miyahira Maria Teresa Raya Rodriguez Carlos Lasso 《Hydrobiologia》2014,735(1):15-44
Based on literature review and malacological collections, 168 native freshwater bivalve and five invasive species have been recorded for 52 hydrographic regions in South America. The higher species richness has been detected in the South Atlantic, Uruguay, Paraguay, and Amazon Brazilian hydrographic regions. Presence or absence data were analysed by Principal Coordinate for Phylogeny-Weighted. The lineage Veneroida was more representative in hydrographic regions that are poorer in species and located West of South America. The Mycetopodidae and Hyriidae lineages were predominant in regions that are richest in species toward the East of the continent. The distribution of invasive species Limnoperna fortunei is not related to species richness in different hydrographic regions there. The species richness and its distribution patterns are closely associated with the geological history of the continent. The hydrographic regions present distinct phylogenetic and species composition regardless of the level of richness. Therefore, not only should the richness be considered to be a criterion for prioritizing areas for conservation, but also the phylogenetic diversity of communities engaged in services and functional aspects relevant to ecosystem maintenance. A plan to the management of this fauna according to particular ecological characteristics and human uses of hydrographic regions is needed. 相似文献
24.
Moreira MF Dos Santos AS Marotta HR Mansur JF Ramos IB Machado EA Souza GH Eberlin MN Kaiser CR Kramer KJ Muthukrishnan S Vasconcellos AM 《Insect biochemistry and molecular biology》2007,37(12):1249-1261
An insoluble white substance was prepared from extracts of eggshells of Aedes aegypti, the yellow fever mosquito and dengue vector. Its infrared and proton NMR spectra were similar to that of standard commercial chitin. This putative chitin-like material, also obtained from ovaries, newly laid and dark eggs, was hydrolyzed in acid and a major product was identified by HPLC to be glucosamine. The eggshell acid hydrolysate was also analyzed by ESI-MS and an ion identical to a glucosamine monoprotonated species was detected. The presence of chitin was also analyzed during different developmental stages of the ovary using a fluorescent microscopy technique and probes specific for chitin. The results showed that a chitin-like material accumulates in oocytes during oogenesis. Streptomyces griseus chitinase pre-treatment of oocytes greatly reduced the chitin-derived fluorescence. Chitinase activity was detected in newborn larvae and eggs prior to hatching. Feeding experiments indicated that the chitin synthesis inhibitor lufenuron inhibited chitin synthesis, either when mosquitoes were allowed to feed directly on lufenuron-treated chickens or when an artificial feeding system was used. Lufenuron inhibited egg hatch, larval development and reduced mosquito viability. These data demonstrate for the first time that (1) a chitin-like material is present in A. aegypti eggs, ovaries and eggshells; (2) a chitin synthesis inhibitor can be used to inhibit mosquito oogenesis; and (3) chitin synthesis inhibitors have potential for controlling mosquito populations. 相似文献
25.
26.
Jorge Mansur Medina Juliany Cola Fernandes Rodrigues Otacilio C Moreira Geórgia Atella Wanderley de Souza Hector Barrabin 《Memórias do Instituto Oswaldo Cruz》2015,110(1):48-55
Phytomonas serpens are flagellates in the family Trypanosomatidae that parasitise the
tomato plant (Solanum lycopersicum L.), which results in fruits with low commercial
value. The tomato glycoalkaloid tomatine and its aglycone tomatidine inhibit the
growth of P. serpens in axenic cultures. Tomatine, like many other saponins, induces
permeabilisation of the cell membrane and a loss of cell content, including the
cytosolic enzyme pyruvate kinase. In contrast, tomatidine does not cause
permeabilisation of membranes, but instead provokes morphological changes, including
vacuolisation. Phytomonas treated with tomatidine show an increased accumulation of
labelled neutral lipids (BODYPY-palmitic), a notable decrease in the amount of
C24-alkylated sterols and an increase in zymosterol content. These
results are consistent with the inhibition of 24-sterol methyltransferase (SMT),
which is an important enzyme that is responsible for the methylation of sterols at
the 24 position. We propose that the main target of tomatidine is the sterols
biosynthetic pathway, specifically, inhibition of the 24-SMT. Altogether, the results
obtained in the present paper suggest a more general effect of alkaloids in
trypanosomatids, which opens potential therapeutic possibilities for the treatment of
the diseases caused by these pathogens. 相似文献
27.
High osmolarity glycerol response PtcB phosphatase is important for Aspergillus fumigatus virulence
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Lizziane K. Winkelströter Vinícius Leite Pedro Bom Patrícia Alves de Castro Leandra Naira Zambelli Ramalho Maria Helena S. Goldman Neil Andrew Brown Ranjith Rajendran Gordon Ramage Elodie Bovier Thaila Fernanda dos Reis Marcela Savoldi Daisuke Hagiwara Gustavo H. Goldman 《Molecular microbiology》2015,96(1):42-54
Aspergillus fumigatus is a fungal pathogen that is capable of adapting to different host niches and to avoid host defenses. An enhanced understanding of how, and which, A. fumigatus signal transduction pathways are engaged in the regulation of these processes is essential for the development of improved disease control strategies. Protein phosphatases are central to numerous signal transduction pathways. To comprehend the functions of protein phosphatases in A. fumigatus, 32 phosphatase catalytic subunit encoding genes were identified. We have recognized PtcB as one of the phosphatases involved in the high osmolarity glycerol response (HOG) pathway. The ΔptcB mutant has both increased phosphorylation of the p38 MAPK (SakA) and expression of osmo‐dependent genes. The ΔptcB strain was more sensitive to cell wall damaging agents, had increased chitin and β‐1,3‐glucan, and impaired biofilm formation. The ΔptcB strain was avirulent in a murine model of invasive pulmonary aspergillosis. These results stress the importance of the HOG pathway in the regulation of pathogenicity determinants and virulence in A. fumigatus. 相似文献
28.
29.
Josh Lawrimore Paula A. Vasquez Michael R. Falvo Russell M. Taylor II Leandra Vicci Elaine Yeh M. Gregory Forest Kerry Bloom 《The Journal of cell biology》2015,210(4):553-564
The centromere is the DNA locus that dictates kinetochore formation and is visibly apparent as heterochromatin that bridges sister kinetochores in metaphase. Sister centromeres are compacted and held together by cohesin, condensin, and topoisomerase-mediated entanglements until all sister chromosomes bi-orient along the spindle apparatus. The establishment of tension between sister chromatids is essential for quenching a checkpoint kinase signal generated from kinetochores lacking microtubule attachment or tension. How the centromere chromatin spring is organized and functions as a tensiometer is largely unexplored. We have discovered that centromere chromatin loops generate an extensional/poleward force sufficient to release nucleosomes proximal to the spindle axis. This study describes how the physical consequences of DNA looping directly underlie the biological mechanism for sister centromere separation and the spring-like properties of the centromere in mitosis. 相似文献
30.
Raju Dash Mir Muhammad Nasir Uddin S.M. Zahid Hosen Zahed Bin Rahim Abu Mansur Dinar Mohammad Shah Hafez Kabir Ramiz Ahmed Sultan Ashekul Islam Md Kamrul Hossain 《Bioinformation》2015,11(12):543-549
Cyclooxygenase-2 (COX-2) catalyzed synthesis of prostaglandin E2 and it associates with tumor growth, infiltration, and metastasis
in preclinical experiments. Known inhibitors against COX-2 exhibit toxicity. Therefore, it is of interest to screen natural compounds
like flavanoids against COX-2. Molecular docking using 12 known flavanoids against COX-2 by FlexX and of ArgusLab were
performed. All compounds showed a favourable binding energy of >-10 KJ/mol in FlexX and > -8 kcal/mol in ArgusLab.
However, this data requires in vitro and in vivo verification for further consideration. 相似文献