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121.
Daniela Camargos Costa Ana Paula Madureira Lara Cotta Amaral Bruno Ant?nio Marinho Sanchez Luciano Teixeira Gomes Cor Jésus Fernandes Fontes Jean Ezequiel Limongi Cristiana Ferreira Alves de Brito Luzia Helena Carvalho 《Memórias do Instituto Oswaldo Cruz》2014,109(1):21-28
The polymerase chain reaction (PCR)-based methods for the diagnosis of malaria
infection are expected to accurately identify submicroscopic parasite carriers.
Although a significant number of PCR protocols have been described, few studies have
addressed the performance of PCR amplification in cases of field samples with
submicroscopic malaria infection. Here, the reproducibility of two well-established
PCR protocols (nested-PCR and real-time PCR for the Plasmodium 18
small subunit rRNA gene) were evaluated in a panel of 34 blood field samples from
individuals that are potential reservoirs of malaria infection, but were negative for
malaria by optical microscopy. Regardless of the PCR protocol, a large variation
between the PCR replicates was observed, leading to alternating positive and negative
results in 38% (13 out of 34) of the samples. These findings were quite different
from those obtained from the microscopy-positive patients or the unexposed
individuals; the diagnosis of these individuals could be confirmed based on the high
reproducibility and specificity of the PCR-based protocols. The limitation of PCR
amplification was restricted to the field samples with very low levels of
parasitaemia because titrations of the DNA templates were able to detect < 3
parasites/µL in the blood. In conclusion, conventional PCR protocols require careful
interpretation in cases of submicroscopic malaria infection, as inconsistent and
false-negative results can occur. 相似文献
122.
Background
If biology is modular then clusters, or communities, of proteins derived using only protein interaction network structure should define protein modules with similar biological roles. We investigate the link between biological modules and network communities in yeast and its relationship to the scale at which we probe the network. 相似文献123.
Rosane Dias Costa Vanessa Amaral Mendon?a Frederico Marianetti Soriani Sandra Lyon Rachel Adriana Penido Ana Maria Duarte Dias Costa Marina Dias Costa Fabio de Souza Terra Mauro Martins Teixeira Carlos Mauricio de Figueiredo Antunes Antonio Lúcio Teixeira 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1051-1056
Leprosy is an infectious and contagious spectral disease accompanied by a series of
immunological events triggered by the host response to the aetiologic agent,
Mycobacterium leprae . The induction and maintenance of the
immune/inflammatory response in leprosy are linked to multiple cell interactions and
soluble factors, primarily through the action of cytokines. The purpose of the
present study was to evaluate the serum levels of tumour necrosis factor (TNF)-α and
its soluble receptors (sTNF-R1 and sTNF-R2) in leprosy patients at different stages
of multidrug treatment (MDT) in comparison with non-infected individuals and to
determine their role as putative biomarkers of the severity of leprosy or the
treatment response. ELISA was used to measure the levels of these molecules in 30
healthy controls and 37 leprosy patients at the time of diagnosis and during and
after MDT. Our results showed increases in the serum levels of TNF-α and sTNF-R2 in
infected individuals in comparison with controls. The levels of TNF-α, but not
sTNF-R2, decreased with treatment. The current results corroborate previous reports
of elevated serum levels of TNF-α in leprosy and suggest a role for sTNF-R2 in the
control of this cytokine during MDT. 相似文献
124.
Vânia C. S. Pankievicz Fernanda P. do Amaral Karina F. D. N. Santos Beverly Agtuca Youwen Xu Michael J. Schueller Ana Carolina M. Arisi Maria. B.R. Steffens Emanuel M. de Souza Fábio O. Pedrosa Gary Stacey Richard A. Ferrieri 《The Plant journal : for cell and molecular biology》2015,81(6):907-919
Nitrogen‐fixing rhizobacteria can promote plant growth; however, it is controversial whether biological nitrogen fixation (BNF) from associative interaction contributes to growth promotion. The roots of Setaria viridis, a model C4 grass, were effectively colonized by bacterial inoculants resulting in a significant enhancement of growth. Nitrogen‐13 tracer studies provided direct evidence for tracer uptake by the host plant and incorporation into protein. Indeed, plants showed robust growth under nitrogen‐limiting conditions when inoculated with an ammonium‐excreting strain of Azospirillum brasilense. 11C‐labeling experiments showed that patterns in central carbon metabolism and resource allocation exhibited by nitrogen‐starved plants were largely reversed by bacterial inoculation, such that they resembled plants grown under nitrogen‐sufficient conditions. Adoption of S. viridis as a model should promote research into the mechanisms of associative nitrogen fixation with the ultimate goal of greater adoption of BNF for sustainable crop production. 相似文献
125.
126.
127.
M.F. Amaral J.M.R. Aranha M.S. Menezes 《Studies on Neotropical Fauna and Environment》2013,48(2):106-110
In the subtropical Atlantic rain forest of southern Brazil, reproduction of the catfish Pimelodella pappenheimi was studied over a two years period in a small coastal stream representing a widely undisturbed aquatic habitat. According to analyses of the gonad status, reproduction is mainly seasonal with a peak in the rainy summer months, consisting of multiple spawning. The average body length of the fishes attaining sexual maturity was the same in both sexes. At the study site summer storms cause flash floods, and heavy rainfalls can suddenly increase the river flow. Reproductive females were found to burrow in the clay palisades of the river sediments which is regarded a behavioural adaptation protecting the offspring from being washed away. 相似文献
128.
Increased ability to predict protein structures is moving research focus towards understanding protein dynamics. A promising approach is to represent protein dynamics through networks and take advantage of well-developed methods from network science. Most studies build protein dynamics networks from correlation measures, an approach that only works under very specific conditions, instead of the more robust inverse approach. Thus, we apply the inverse approach to the dynamics of protein dihedral angles, a system of internal coordinates, to avoid structural alignment. Using the well-characterized adhesion protein, FimH, we show that our method identifies networks that are physically interpretable, robust, and relevant to the allosteric pathway sites. We further use our approach to detect dynamical differences, despite structural similarity, for Siglec-8 in the immune system, and the SARS-CoV-2 spike protein. Our study demonstrates that using the inverse approach to extract a network from protein dynamics yields important biophysical insights. 相似文献
129.
Alejandro O Luquetti Suelene Brito do Nascimento Tavares Liliane da Rocha Siriano Rozangela Amaral de Oliveira Dayse Elizabeth Campos Cicilio Alves de Morais Enio Chaves de Oliveira 《Memórias do Instituto Oswaldo Cruz》2015,110(3):369-376
Transmission of Trypanosoma cruzi during pregnancy is estimated tooccur in less than 20% of infected mothers; however, the etiopathogenesis is notcompletely understood. The Centre for Studies on Chagas Disease provides confirmationof T. cruzi infection for individuals living in central Brazil.In this retrospective hospital-based study, all requests for diagnosis of T.cruzi infection in individuals less than 21 years old from 1994-2014 weresearched. We end with 1,211 individuals and their respective infected mothers.Congenital transmission of infection was confirmed in 24 individuals (2%) in centralBrazil, an area where the main T. cruzi lineage circulating inhumans is TcII. This low prevalence of congenital Chagas disease is discussed inrelation to recent findings in the south region of Brazil, where TcV is the mainlineage and congenital transmission has a higher prevalence (approximately 5%),similar to frequencies reported in Argentina, Paraguay and Bolivia. This is the firstreport to show geographical differences in the rates of congenital transmissionof T. cruzi and the relationship between the prevalence ofcongenital transmission and the type of Tc prevalent in each region. 相似文献
130.
Ismail Eş José Daniel Gonçalves Vieira André Corrêa Amaral 《Applied microbiology and biotechnology》2015,99(5):2065-2082
Immobilization is one of the most effective and powerful tools used in industry, which has been studied and improved since the last century. Various immobilization techniques and support materials have been used on both laboratory and industrial scale. Each immobilization technique is applicable for a specific production mostly depending on the cost and sensibility of process. Compared to free biocatalyst systems, immobilization techniques often offer better stability, increased activity and selectivity, higher resistance, improved separation and purification, reuse of enzymes, and consequently more efficient process. Recently, many reviews have been published about immobilization systems; however, most of them have focused on a specific application or not emphasized in details. This review focuses on most commonly used techniques in industry with many recent applications including using bioreactor systems for industrial production. It is also aimed to emphasize the advantages and disadvantages of the immobilization techniques and how these systems improve process productivity compared to non-immobilized systems. 相似文献