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111.
112.
Lilian M. A. Flores Lorenzo R. S. Zanette Francisca S. Araujo 《Biodiversity and Conservation》2018,27(2):311-328
Habitat complexity is directly correlated to insect diversity in most natural environments. Structural complexity reflects an increase in vertical stratification and plant diversity and often leads to a greater availability of floral resources and nesting sites. Efficient conservation strategies require understanding of how changes in habitat structure affect insects that provide essential ecosystem services. We analyzed how the diversity and species composition of bees and wasps that nest in pre-existing cavities is affected by habitat complexity. Our study was developed in the semiarid region of northeastern Brazil, in the Ubajara National Park and surrounding area. Four types of habitats within two physiognomies were sampled for two consecutive years. We used 120 trap-nest (9000 cavities) distributed in 40 sample points. Overall, 657 cavities were occupied by 11 species of bees, nine of wasps, and six of cleptoparasitic/parasitoids. Bees and wasp diversity increases with habitat complexity. While species richness was higher in more complex physiognomies, abundance was higher in disturbed areas. Species composition also varied with habitat structure. Habitat simplification has adverse effects on the diversity and composition of assemblages. These effects are stronger in more complex habitats indicating that conservation of humid habitats within semiarid areas is essential to maintain bee and wasp regional diversity. 相似文献
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WANG Jing ZHANG Xiaobing PENG Junping YANG E BIN Wen YANG Jian DONG Jie SUN Lilian XU Xingye JIN Qi 《中国科学C辑(英文版)》2006,49(1):46-52
Comparative Genomic Hybridization (CGH) microarray analysis was used to compare the genomic compositions of all eighteen Shigella boydii serotype representative strains. The results indicated the genomic “backbone” of this subgroup contained 2552 ORFs homologous
to nonpathogenic E. coli K12. Compared with the genome of K12199 ORFs were found to be absent in all S. boydii serotype representatives, including mainly outer membrane protein genes and O-antigen biosynthesis genes. Yet the specific
ORFs of S. boydii subgroup contained basically bacteriophage genes and the function unknown (FUN) genes. Some iron metabolism, transport and
type II secretion system related genes were found in most representative strains. According to the CGH phylogenetic analysis,
the eighteen S. boydii serotype representatives were divided into four groups, in which serotype C13 strain was remarkably distinguished from the
other serotype strains. This grouping result corresponded to the distribution of some metabolism related genes. Furthermore,
the analysis of genome backbone genes, specific genes, and the phylogenetic trees allowed us to discover the evolution laws
of S. boydii and to find out important clues to pathogenesis research, vaccination and the therapeutic medicine development. 相似文献
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Alisson L. da Rocha Giovana R. Teixeira Ana P. Pinto Gustavo P. de Morais Luciana da C. Oliveira Larissa Gaioto de Vicente Lilian E. C. M. da Silva José R. Pauli Dennys E. Cintra Eduardo R. Ropelle Leandro P. de Moura Rania A. Mekary Ellen C. de Freitas Adelino S. R. da Silva 《Journal of cellular physiology》2018,233(11):8850-8861
117.
Diet of Neotropical parrots is independent of phylogeny but correlates with body size and geographical range 下载免费PDF全文
Analia Benavidez Facundo Xavier Palacio Luis Osvaldo Rivera Ada Lilian Echevarria Natalia Politi 《Ibis》2018,160(4):742-754
Body mass and geographical range are two main drivers of diet in animals, yet how these factors influence diet in the morphologically and ecologically diverse avian group of Psittaciformes is little known. We reviewed current knowledge of the diet of Neotropical parrots and assessed the relation between diet (breadth and composition), phylogeny, body mass and geographical range. Diet has been documented for 98 of 165 species, but information is available only for 34 of 59 threatened species, and countries with high species diversity (> 20 species) had few studies (one to seven). Neotropical parrot species consumed 1293 plant species of 125 families. When assessing the relative frequency of different food items in the diet (seed, fruits, flowers, leaves, nectar, bark and stems), we found that parrots mostly exploited seeds (41.9%) and fruits (38.3%) of native species. Diet overlap was very low among genera (0.006–0.321). At the species level, geographical range and body size explained the variation in diet composition. In particular, small parrots of restricted distribution had a distinct diet composition relative to either large or widely distributed species. Although body size and geographical range showed phylogenetic inertia, diet was independent of phylogenetic history. Our review not only reveals ecological factors explaining diet in a generalist group but also exposes information gaps across the Neotropical region. 相似文献
118.
The Effects of the Organic Flame‐Retardant 1,2‐Dibromo‐4‐(1,2‐dibromoethyl) Cyclohexane (TBECH) on Androgen Signaling in Human Prostate Cancer Cell Lines 下载免费PDF全文
Lilian I. L. Wong Alexandra R. Reers Heidi A. Currier Tony D. Williams Michael E. Cox John E. Elliott Timothy V. Beischlag 《Journal of biochemical and molecular toxicology》2016,30(5):239-242
The effects of the organic flame retardant 1,2‐Dibromo‐4‐(1,2‐dibromoethyl) cyclohexane (TBECH) on androgen receptor target gene expression were examined in the human LNCaP prostate cancer cell line. While γ‐/δ‐TBECH alone led to a significant increase in prostate‐specific antigen (PSA) mRNA accumulation, both the α‐/‐TBECH and γ‐/δ‐TBECH mixtures repressed androgen‐inducible PSA mRNA and protein accumulation in human LNCaP cells. Thus, we hypothesize that isomeric mixtures of TBECH may act as partial agonists of the androgen receptor. 相似文献
119.
Ronivaldo Rodrigues da Silva Tatiane Beltramini Souto Tássio Brito de Oliveira Lilian Caroline Gonçalves de Oliveira Daniel Karcher Maria Aparecida Juliano Luiz Juliano Arthur H. C. de Oliveira André Rodrigues Jose C. Rosa Hamilton Cabral 《Journal of industrial microbiology & biotechnology》2016,43(8):1059-1069
In this study, we detail the specificity of an aspartic peptidase from Rhizomucor miehei and evaluate the effects of this peptidase on clotting milk using the peptide sequence of k-casein (Abz-LSFMAIQ-EDDnp) and milk powder. Molecular mass of the peptidase was estimated at 37 kDa, and optimum activity was achieved at pH 5.5 and 55 °C. The peptidase was stable at pH values ranging from 3 to 5 and temperatures of up 45 °C for 60 min. Dramatic reductions in proteolytic activity were observed with exposure to sodium dodecyl sulfate, and aluminum and copper (II) chloride. Peptidase was inhibited by pepstatin A, and mass spectrometry analysis identified four peptide fragments (TWSISYGDGSSASGILAK, ASNGGGGEYIFGGYDSTK, GSLTTVPIDNSR, and GWWGITVDRA), similar to rhizopuspepsin. The analysis of catalytic specificity showed that the coagulant activity of the peptidase was higher than the proteolytic activity and that there was a preference for aromatic, basic, and nonpolar amino acids, particularly methionine, with specific cleavage of the peptide bond between phenylalanine and methionine. Thus, this peptidase may function as an important alternative enzyme in milk clotting during the preparation of cheese. 相似文献
120.
J. Marc Fremy Lilian Puech Sophie Krys Sylviane Dragacci 《Journal of applied phycology》1999,11(4):377-384
Okadaic acid and dinophysistoxins are produced by some marine unicellular algae from the plankton and also benthic microalgae
and may accumulate in shellfish. These phycotoxins are involved in a gastrointestinal syndrome called diarrhetic shellfish
poisoning (DSP), which occurs in humans after consumption of bivalve molluscs. Thousands cases of human poisonings in Europe
were caused by consumption of toxic shellfish during the past decade. The rapid detection and the reliable determination of
the main phycotoxins implicated in DSP are a major concern for governmental institutions in charge of the sanitary control
of seafood safety. Analytical procedures for the detection and determination of DSP toxins can be classified as: bioassays,
biochemical methods including immunoassays, or physicochemical methods. Although a large number of methods have been developed,
none have been officially validated. A complete panel of tools for DSP toxin analysis should include screening, investigation,
and confirmation methods. This paper presents a compilation of recent developments and optimisations of these methods.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献