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71.
A secretory form of human α3-fucosyltransferase IX (sFUT9) was overexpressed in Spodoptera frugiperda (Sf9) insect cells using the stable expression vector pIB/V5-His-TOPO and the signal sequence of human interleukin 2 for
efficient secretion. sFUT9 was active and its three potential N-glycosylation sites were occupied. sFUT9 efficiently fucosylated the type II acceptors Galbeta4GlcNAC-R and Fucalpha2Galbeta4GlcNAc-R
(R = (CH2)3NHCO(CH2)5–NH-biotin) but not the corresponding sialylated acceptor, and only very poorly the type I (Galbeta3GlcNAc-R)
related acceptors. sFUT9 showed a clear preference for glycoproteins containing type II acceptors, with values of 121, 113
and 110 microU/million cell for asialofetuin, erythropoietin and asialoerythropoietin, respectively, values approximately
11-fold higher than those obtained for the small acceptors. 相似文献
72.
Laurentino EC Ruiz JC Brito LO Fiandt M Nicoletti LM Jamur MC Oliver C Tosi LR Cruz AK 《International journal for parasitology》2007,37(7):735-742
The use of transposable elements as a gene-trapping strategy is a powerful tool for gene discovery. Herein we describe the development of a transposable system, based on the bacterial Tn5 transposon, which has been used successfully in Leishmania braziliensis. The transposon carries the neomycin phosphotransferase gene, which is expressed only when inserted in-frame with a Leishmania gene present in the target DNA. Four cosmid clones from a L. braziliensis genomic library were used as targets in transposition reactions and four insertional libraries were constructed and transfected in L. braziliensis. Clones resistant to G418 were selected and analysed by immunofluorescence in order to identify the subcellular localisation of the protein coded by the trapped gene. A definitive subcellular localisation for neomycin phosphotransferase/targeted protein fusion was not obtained in any of the four Leishmania clones investigated. However, the constructed transposable element is highly efficient considering the frequency of insertion in large targets and is therefore a useful tool for functional genetic studies in Leishmania. Our data confirm the utility of the Tn5 transposon system for insertion of sequencing priming sites into target DNA. Furthermore, the high frequency of insertion and even distribution are important in studying genomic regions bearing long and polymorphic repetitive sequences. 相似文献
73.
Contrasting patterns of mitochondrial and microsatellite genetic structure among Western European populations of tawny owls (Strix aluco) 总被引:2,自引:2,他引:0
Brito PH 《Molecular ecology》2007,16(16):3423-3437
A recent study of mitochondrial phylogeography of tawny owls (Strix aluco) in western Europe suggested that this species survived the Pleistocene glaciations in three allopatric refugia located in Iberia, Italy, and the Balkans, and the latter was likely the predominant source of postglacial colonization of northern Europe. New data from seven microsatellite loci from 184 individual owls distributed among 14 populations were used to assess the genetic congruence between nuclear and mitochondrial DNA (mtDNA) markers. Microsatellites corroborated the major phylogeographical conclusions reached on the basis of the mtDNA sequences, but also showed important differences leading to novel inferences. Microsatellites corroborated the three major refugia and supported the Balkan origin of northern populations. When corrected for differences in effective population size, microsatellites and mtDNA yielded generally congruent overall estimates of population structure (N*ST=0.12 vs. RST=0.16); however, there was substantial heterogeneity in the RST among the seven nuclear loci that was not correlated with heterozygosity. Populations representing the Balkans postglacial expansion interact with populations from the other two refugia forming two clines near the Alps and the Pyrenees. In both cases, the apparent position of the contact zones differed substantially between markers due to the genetic composition of populations sampled in northern Italy and Madrid. Microsatellite data did not corroborate the lower genetic diversity of northern, recently populated regions as was found with mtDNA; this discrepancy was taken as evidence for a recent bottleneck recovery. Finally, this study suggests that congruence among genetic markers should be more likely in cases of range expansion into new areas than when populations interact across contact zones. 相似文献
74.
Seawater is a complex corrosive system, and biofouling is one of the factors that influences corrosion processes. The behaviour of corrosion associated with the development of macrofouling was investigated during the first 6 months of the successional process. Three treatments were compared: the 'Control' treatment (absence of macrofouling); 'Community' treatment, and 'Barnacle' treatment, where other macroorganisms were excluded. In the Community treatment, the dominant organisms were filamentous macroalgae (23.73%), barnacles (17.51%), hydroids (16.96%) and encrusting bryozoans (9.58%). In the Barnacle treatment, the cover varied between 39.38% and 62.50%. The corrosion potential ranged from -665.75 to -517.50 mV(Ag/AgC l((KCl))) and could not be associated with fouling development. The highest corrosion rate in the control suggests that macrofouling provides a protection against mass loss. The highest percentage of localised attacks was found in the Community treatment. This may indicate that not only barnacles, but also other organisms induce localised corrosion. 相似文献
75.
The spatial and temporal variation of macroinvertebrate assemblages was studied in two Portuguese commercial rice agroecosystems
under the effect of field management involving the application of pesticides and fertilizers. A faunal succession of organisms
was observed on both fields. Grazers were the first to colonize the paddies after a dry period when pesticides were applied,
followed by development into nymphs and by an increase in the abundance of the species after the application of fertilizers.
At the end of the season when no pesticides or fertilizers were applied, the communities changed with the presence of adult
predators as a result of an increase in prey. Insecticide application revealed specific taxa increase due to the lack of competition
with the target organism. Macroinvertebrates tended to prefer infested field margins with aquatic, submerged vegetation, revealing
a spatial distribution along the paddies. Two different sampling devices were used and proved necessary in documenting the
macroinvertebrate communities (grab for benthic and hand-net for pelagic organisms). 相似文献
76.
Martins Renato T. Brito Janaina Dias-Silva Karina Leal Ceclia G. Leito Rafael P. Oliveira Vivian C. Oliveira-Jnior Jos M. B. de Paula Felipe R. Roque Fabio O. Hamada Neusa Juen Leandro Nessimian Jorge L. Pompeu Paulo S. Hughes Robert M. 《Hydrobiologia》2022,849(10):2281-2298
Hydrobiologia - Stream degradation in Amazonia is outpacing our ability to effectively monitor it for three key reasons: (1) Many changes are cumulative and occur gradually; (2) Scientists have... 相似文献
77.
Martins Renato Tavares de Freitas Silva Rafael Augusto Pinheiro Pinto Valria Arajo Braule Medeiros Adriana Oliveira Brito Laisa Hamada Neusa 《Hydrobiologia》2022,849(16):3531-3544
Hydrobiologia - We used experimental chambers to evaluate the effect of the temperature increasing and microbial conditioning degree on the survival and leaf consumption of two plant species... 相似文献
78.
Bernardes-Engemann Andréa Reis Almeida Marcos de Abreu Bison Ividy Rabello Vanessa Brito de Souza Ramos Mariana Lucy Mesquita Pereira Sandro Antonio Almeida-Paes Rodrigo de Lima Brasil Arthur Willian Zancopé-Oliveira Rosely Maria 《Mycopathologia》2022,187(4):375-384
Mycopathologia - Feline sporotrichosis has emerged as an important public health issue in some countries, especially Brazil. Currently, zoonotic transmission of Sporothrix brasiliensis by domestic... 相似文献
79.
Francinaldo Soares Silva Jefferson Mesquita Brito Benedita Maria Costa Neta Shelre Emile Pereira Duarte Lobo 《Memórias do Instituto Oswaldo Cruz》2015,110(6):801-803
Hoover Pugedo light traps were modified for use with green and blue-light-emitting
diodes to trap phlebotomine sandflies in northeastern Brazil. A total of 2,267
specimens belonging to eight genera and 15 species were sampled. The predominant
species were Nyssomyia whitmani(34.41%) and Micropygomyia
echinatopharynx(17.25%).The green LED trap prevailed over the blue and
control lights; however, no statistically significant difference could be detected
among the three light sources. Even without statistical significance, we suggest
using LEDs as an attractant for the capture of sandflies because of several
advantages over the conventional method with incandescent lamps. 相似文献