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71.
72.
73.
Damasceno-Sá JC Carneiro CN DaMatta RA Samuels RI Terra WR Silva CP 《Journal of insect physiology》2007,53(6):592-600
The development of perimicrovillar membranes (PMM) from midgut cells of starved and fed Dysdercus peruvianus was studied by using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and assays for specific enzymatic markers of the perimicrovillar membranes (alpha-glucosidase), perimicrovillar space (aminopeptidase) and microvillar membranes (beta-glucosidase). High activities of these enzymes were observed 6h post-feeding and significant production of membranes was observed at 30 h post-feeding. In the gut cells of starved insects, the rough endoplasmic reticulum was organized in concentric bundles, with a greater number of mitochondria in the cellular apex. The presence of electron dense double-membrane vesicles and the production of PMM were not observed in this condition. Thirty hours post-feeding, a disorganization of the rough endoplasmic reticulum was observed, and it was possible to see double-membrane vesicles close to the cell apex. The membrane system formation was evident with a significant development of PMM in the midgut lumen. The luminal surface of the midgut during starvation and up to 48 h post-feeding was monitored using SEM. It was demonstrated that in the starved condition, the PMM was virtually absent from gut cells, except at the base of the microvilli. At 6h post-feeding, the microvilli were already completely covered with PMM, but with a maximum of PMM formation seen at 30 h post-feeding. Signals of PMM degradation were observed 48 h after pulse feeding. 相似文献
74.
Martin Sander Tatiana Coelho Balbão Michael John Polito Erli Schneider Costa Ana Paula Bertoldi Carneiro 《Polar Biology》2007,30(5):659-661
We examined the breeding populations of chinstrap penguins (Pygoscelis antarctica) on Chabrier Rock and Shag Island within Admiralty Bay, King George Island, South Shetland Islands, Antarctica from 2002
to 2004. When comparing our results to historic data from 1979, we found an overall decline of 57% in the last 25 years, mirroring
the population trend of this species in other regions of the Antarctic Peninsula. Our results are discussed in relation to
factors hypothesized to be driving the declines found at other sites, as well as the importance of consistent annual censuses
to accurately determine population trends. 相似文献
75.
76.
Development, characterization, and comparative analysis of polymorphism at common bean SSR loci isolated from genic and genomic sources. 总被引:4,自引:0,他引:4
Luiz Ricardo Hanai Tatiana de Campos Luis Eduardo Aranha Camargo Luciana Lasry Benchimol Anete Pereira de Souza Maeli Melotto Sérgio Augusto Moraes Carbonell Alisson Fernando Chioratto Luciano Consoli Eduardo Fernando Formighieri Marcos Vinícius Bohrer Monteiro Siqueira Siu Mui Tsai Maria Lucia Carneiro Vieira 《Génome》2007,50(3):266-277
Microsatellites or SSRs (single sequence repeats) have been used to construct and integrate genetic maps in crop species, including Phaseolus vulgaris. In the present study, 3 cDNA libraries generated by the Bean EST project (http://lgm.esalq.usp.br/BEST/), comprising a unigene collection of 3126 sequences and a genomic microsatellite-enriched library, were analyzed for the presence of SSRs. A total of 219 expressed sequence tags (ESTs) were found to carry 240 SSRs (named EST-SSR), whereas 714 genomic sequences contained 471 SSRs (named genomic-SSR). A subset of 80 SSRs, 40 EST-SSRs, and 40 genomic-SSRs were evaluated for molecular polymorphism in 23 genotypes of cultivated beans from the Mesoamerican and Andean genetic pools, including Brazilian cultivars and 2 related species. Of the common bean genotypes, 31 EST-SSR loci were polymorphic, yielding 2-12 alleles as compared with 26 polymorphic genomic-SSRs, accounting for 2-7 alleles. Cluster analysis from data using both genic and genomic-SSR revealed a clear separation between Andean and Mesoamerican beans. The usefulness of these loci for distinguishing bean genotypes and genetic mapping is discussed. 相似文献
77.
Marcelo De Franco Patrícia dos Santos Carneiro Luciana Carla Peters Francisca Vorraro Andrea Borrego Orlando Garcia Ribeiro Nancy Starobinas Wafa Koury Cabrera Olga Martinez Ibañez 《Mammalian genome》2007,18(4):263-269
Lines of mice were obtained by selective breeding for maximum (AIRmax) or minimum (AIRmin) acute inflammation. They present
distinct neutrophil influx and show frequency disequilibrium of the solute carrier family 11a member 1
(Slc11a1) alleles. This gene is involved in ion transport at the endosomes within macrophages and neutrophils, interfering in their
activation. Homozygous AIRmax and AIRmin sublines for the Slc11a1 gene were produced to examine the interaction of this gene with the acute inflammatory loci. The present work investigated
wound-healing traits in AIRmax and AIRmin mice, in F1 and F2 intercrosses, and in Slc11a1 sublines. Two-millimeter ear punches were made in the mice and hole closure was measured during 40 days. AIRmax mice demonstrated
significant tissue repair while AIRmin mice did not. Significant differences between the responses of male and female mice
were also observed. Wound-healing traits demonstrated a correlation with neutrophil influx in F2 populations. AIRmax
SS
showed higher ear-wound closure than AIRmax
RR
mice, suggesting that the Slc11a1
S allele favored ear tissue repair. QTL analysis has detected two inflammatory loci modulating ear wound healing on chromosomes
1 and 14. These results suggest the involvement of the acute inflammation modifier QTL in the wound-healing phenotype. 相似文献
78.
Ana Claudia Guerra Araujo Rosana Falcão Vera Tavares de Campos Carneiro 《Sexual plant reproduction》2007,20(3):109-121
Gametophytic organization, fertilization and reproductive success are described for the fertile diploid Brachiaria brizantha accession BRA-002747 which is being raised for use in Brachiaria breeding programs, as well as to understand and control of apomixis in this genus. The current paper reports on reproductive
biology and analysis of seed set in field experiments during three consecutive years. Unsuccessful seed production in this
plant is believed to correlate with early inbreeding depression, based on the reproductive features analyzed. Caryopsis development
was observed using differential interference contrast microscopy with seed set determined by the number of self- and open-pollinated
pistils that fully developed into viable seeds. Developing and mature female and male gametophytes were observed in the context
of flower phenology, morphology and anthesis patterns. Pollen viability was determined by acetocarmine staining and by observation
of germination in vivo, which was also used to observe pollen tube/pistil interaction. Although normal development was observed
in floral structures, anthesis and gametophytes, seed set was low, with 2 and 6% in self- and open-pollination, respectively,
producing seed. Variations observed in the female organs, such as the presence of a hermaphrodite flower in 50% of the inferior
floscules and the presence of multiple embryo sacs of the Polygonum type within the same ovule in 15% of the pistils, are
not related to low fertility. The majority of pollen grains are viable, in spite of the reduced number of pollen tubes within
the style and ovary carpel, and a developing caryopsis was observed in 70% of self-pollinated pistils, indicating successful
double fertilization from 2 days after anthesis (DAA). Nevertheless, abortion gradually increased from 2 until 7 DAA and remains
elevated until 12 DAA, when caryopsis maturity is achieved. These data confirm low seed set in this accession and indicate
that low fertility is not a consequence of abnormalities, either in the floral or gamete structures, or pollen tube rejection,
but most likely a consequence of inbreeding depression. 相似文献
79.
Background
Paulinella chromatophora is a freshwater filose amoeba with photosynthetic endosymbionts (chromatophores) of cyanobacterial origin that are closely related to free-living Prochlorococcus and Synechococcus species (PS-clade). Members of the PS-clade of cyanobacteria contain a proteobacterial form 1A RubisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) that was acquired by horizontal gene transfer (HGT) of a carboxysomal operon. In rDNA-phylogenies, the Paulinella chromatophore diverged basal to the PS-clade, raising the question whether the HGT occurred before or after the split of the chromatophore ancestor. 相似文献80.
Gonçalves Renata C. Carvalho Celso Carneiro Michels Monique Abatti Mariane R. Manfredini Andressa Silva Milena C. Dominguini Diogo Steckert Amanda Mina Francielle Streck Emílio Budni Josiane Dal-Pizzol Felipe 《Neurochemical research》2022,47(3):613-621
Neurochemical Research - Critical illness encompasses a wide spectrum of life-threatening clinical conditions requiring intensive care. Our objective was to evaluate cognitive, inflammatory and... 相似文献