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71.
72.
Verónica Guajardo Simón Solís Boris Sagredo Felipe Gainza Carlos Mu?oz Ksenija Gasic Patricio Hinrichsen 《PloS one》2015,10(5)
Linkage maps are valuable tools in genetic and genomic studies. For sweet cherry, linkage maps have been constructed using mainly microsatellite markers (SSRs) and, recently, using single nucleotide polymorphism markers (SNPs) from a cherry 6K SNP array. Genotyping-by-sequencing (GBS), a new methodology based on high-throughput sequencing, holds great promise for identification of high number of SNPs and construction of high density linkage maps. In this study, GBS was used to identify SNPs from an intra-specific sweet cherry cross. A total of 8,476 high quality SNPs were selected for mapping. The physical position for each SNP was determined using the peach genome, Peach v1.0, as reference, and a homogeneous distribution of markers along the eight peach scaffolds was obtained. On average, 65.6% of the SNPs were present in genic regions and 49.8% were located in exonic regions. In addition to the SNPs, a group of SSRs was also used for construction of linkage maps. Parental and consensus high density maps were constructed by genotyping 166 siblings from a ‘Rainier’ x ‘Rivedel’ (Ra x Ri) cross. Using Ra x Ri population, 462, 489 and 985 markers were mapped into eight linkage groups in ‘Rainier’, ‘Rivedel’ and the Ra x Ri map, respectively, with 80% of mapped SNPs located in genic regions. Obtained maps spanned 549.5, 582.6 and 731.3 cM for ‘Rainier’, ‘Rivedel’ and consensus maps, respectively, with an average distance of 1.2 cM between adjacent markers for both ‘Rainier’ and ‘Rivedel’ maps and of 0.7 cM for Ra x Ri map. High synteny and co-linearity was observed between obtained maps and with Peach v1.0. These new high density linkage maps provide valuable information on the sweet cherry genome, and serve as the basis for identification of QTLs and genes relevant for the breeding of the species. 相似文献
73.
Ana Riesgo Sergio Taboada Laura Sánchez-Vila Joan Solà Andrea Bertran Conxita Avila 《PloS one》2015,10(3)
During embryogenesis, organisms with lecithotrophic indirect development usually accumulate large quantities of energetic reserves in the form of yolk that are necessary for larval survival. Since all sponges have lecithotrophic development, yolk formation is an ineludible step of their embryogenesis. Sponge yolk platelets have a wide range of morphological forms, from entirely lipid or protein platelets to a combined platelet showing both lipids and proteins and even glycogen. So far, there are no comparative studies on the nature and content of yolk in congeneric species of sponges inhabiting contrasting environments, which could have putative effects on the larval adaptation to environmental conditions. Here, we have taken advantage of the worldwide distribution of the sponge genus Mycale, in order to compare the embryogenesis and yolk formation in two species inhabiting contrasting latitudinal areas: M. acerata from Antarctic waters and M. laevis from the Caribbean. We have compared their brooded embryos and larvae using scanning and transmission electron microscopy, and calculated their energetic signatures based on the nature of their yolk. While the general morphological feature of embryos and larvae of both species were very similar, the main difference resided in the yolk nature. The Antarctic species, M. acerata, showed exclusively lipid yolk, whereas the Caribbean species, M. laevis, showed combined platelets of lipids and proteins and less frequently protein yolk platelets. The larvae of M. acerata were estimated to possess a two-fold energetic signature compared to that of M. laevis, which may have important ecological implications for their survival and for maintaining large population densities in the cold waters of the Southern Ocean. 相似文献
74.
Elizabeth J. Akin Laura Solé Sulayman D. Dib-Hajj Stephen G. Waxman Michael M. Tamkun 《PloS one》2015,10(4)
During axonal maturation, voltage-gated sodium (Nav) channels accumulate at the axon initial segment (AIS) at high concentrations. This localization is necessary for the efficient initiation of action potentials. The mechanisms underlying channel trafficking to the AIS during axonal development have remained elusive due to a lack of Nav reagents suitable for high resolution imaging of channels located specifically on the cell surface. Using an optical pulse-chase approach in combination with a novel Nav1.6 construct containing an extracellular biotinylation domain we demonstrate that Nav1.6 channels are preferentially inserted into the AIS membrane during neuronal development via direct vesicular trafficking. Single-molecule tracking illustrates that axonal channels are immediately immobilized following delivery, while channels delivered to the soma are often mobile. Neither a Nav1.6 channel lacking the ankyrin-binding motif nor a chimeric Kv2.1 channel containing the Nav ankyrinG-binding domain show preferential AIS insertion. Together these data support a model where ankyrinG-binding is required for preferential Nav1.6 insertion into the AIS plasma membrane. In contrast, ankyrinG-binding alone does not confer the preferential delivery of proteins to the AIS. 相似文献
75.
Sílvia Saumell Francesc Solé Leonor Arenillas Julia Montoro David Valcárcel Carme Pedro Carmen Sanzo Elisa Lu?o Teresa Giménez Montserrat Arnan Helena Pomares Raquel De Paz Beatriz Arrizabalaga Andrés Jerez Ana B. Martínez Judith Sánchez-Castro Juan D. Rodríguez-Gambarte José M. Raya Eduardo Ríos María Rodríguez-Rivera Blanca Espinet Lourdes Florensa 《PloS one》2015,10(6)
Isolated trisomy 8 is not considered presumptive evidence of myelodysplastic syndrome (MDS) in cases without minimal morphological criteria. One reason given is that trisomy 8 (+8) can be found as a constitutional mosaicism (cT8M). We tried to clarify the incidence of cT8M in myeloid neoplasms, specifically in MDS, and the diagnostic value of isolated +8 in MDS. Twenty-two MDS and 10 other myeloid neoplasms carrying +8 were studied. Trisomy 8 was determined in peripheral blood by conventional cytogenetics (CC) and on granulocytes, CD3+ lymphocytes and oral mucosa cells by fluorescence in situ hybridization (FISH). In peripheral blood CC, +8 was seen in 4/32 patients. By FISH, only one patient with chronic myelomonocytic leukemia showed +8 in all cell samples and was interpreted as a cT8M. In our series +8 was acquired in all MDS. Probably, once discarded cT8M by FISH from CD3+ lymphocytes and non-hematological cells, +8 should be considered with enough evidence to MDS. 相似文献
76.
Development of sucrose-utilizing Escherichia coli K-12 strain by cloning β-fructofuranosidases and its application for l-threonine production 总被引:1,自引:0,他引:1
Jeong Wook Lee Sol Choi Jin Hwan Park Claudia E. Vickers Lars K. Nielsen Sang Yup Lee 《Applied microbiology and biotechnology》2010,88(4):905-913
Sucrose is one of the most promising carbon sources for industrial fermentation. To achieve sucrose catabolism, the sucrose
utilization operons have been introduced into microorganisms that are not able to utilize sucrose. However, the rates of growth
and sucrose uptake of these engineered strains were relatively low to be successfully employed for industrial applications.
Here, we report a practical example of developing sucrose-utilizing microorganisms using Escherichia coli K-12 as a model system. The sucrose utilizing ability was acquired by introducing only β-fructofuranosidase from three different
sucrose-utilizing organisms (Mannheimia succiniciproducens, E. coli W, and Bacillus subtilis). Among them, the M. succiniciproducens β-fructofuranosidase was found to be the most effective for sucrose utilization. Analyses of the underlying mechanism revealed
that sucrose was hydrolyzed into glucose and fructose in the extracellular space and both liberated hexoses could be transported
by their respective uptake systems in E. coli K-12. To prove that this system can also be applied for the production of useful metabolites, the M. succiniciproducens β-fructofuranosidase was introduced into the engineered l-threonine production strain of E. coli K-12. This recombinant strain was able to produce 51.1 g/L l-threonine by fed-batch culture, resulting in an overall yield of 0.284 g l-threonine per g sucrose. This simple approach to make E. coli K-12 to acquire sucrose-utilizing ability and its successful biotechnological application can be employed to develop sustainable
bioprocesses using renewable biomass. 相似文献
77.
Susana Sevilla-Espinosa Maricela Solórzano-Campo Ricardo Bello-Mendoza 《Biodegradation》2010,21(5):737-751
The use of anaerobic processes to treat low-strength wastewater has been increasing in recent years due to their favourable
performance-costs balance. For optimal results, it is necessary to identify reactor configurations that are best suited for
this kind of application. This paper reports on the comparative study carried out with two high-rate anaerobic reactor systems
with the objective of evaluating their performances when used for the treatment of low-strength, complex wastewater. One of
the systems is the commonly used up-flow anaerobic sludge blanket (UASB) reactor. The other is the up-flow staged sludge bed
(USSB) system in which the reactor was divided longitudinally into 3, 5 and 7 compartments by the use of baffles. The reactors
(9 l) were fed with a synthetic, soluble and colloidal waste (chemical oxygen demand (COD) < 1000 mg/l) and operated at 28°C
and 24 h hydraulic retention time. Intermediate flow hydraulics, between plug-flow and completely-mixed, in the UASB and 7
stages USSB reactors allowed efficient degradation of substrates with minimum effluent concentrations. Low number of compartments
in the USSB reactors increased the levels of short-circuiting thus reducing substrate removal efficiencies. All reactors showed
high COD removal efficiencies (93–98%) and thus can be regarded as suitable for the treatment of low strength, complex wastewater.
Staged anaerobic reactors can be a good alternative for this kind of application provided they are fitted with a large enough
(≥7) number of compartments to fully take advantage of their strengths. Scale factors seem to have influenced importantly
on the comparison between one and multi staged sludge-bed reactors and, therefore, observations made here could change at
larger reactor volumes. 相似文献
78.
Antonio Hernández Mijares Eva Solá Izquierdo Katherinne García Malpartida Danilo Verge 《Endocrinología y nutrición》2010,57(8):376-380
The widespread use of insulin analogues is based not only on the pharmacokinetics of these preparations, which is much closer to the physiology of insulin secretion under normal conditions, but also on their safety and effectiveness. The publication of a possible association between the use of a long-acting insulin analogue (glargine) and breast cancer has caused uneasiness among the medical community regarding the safety of these analogues.The mechanism of increased tumor activity of insulin analogues is explained by the fact that they act through insulin receptors (IR) and insulin-like growth factor-1 (IGF-1R), stimulating cell growth and inhibiting apoptosis. There are two major mechanisms: an increase in the binding time of insulin to IR and increased activation of IGF-1R. Therefore, to evaluate the safety of an analogue, the slower dissociation rate from its insulin receptor must be excluded, as well as the increased affinity for the IGF-1 receptor. This is equivalent to an index of mitogenic/metabolic activity of less than 1. These aspects can only be evaluated through study of cell lines and animal testing, which are reductionist models that cannot always be extrapolated to humans. To date, there are no data to question the safety of insulin analogues in general. However, the results of observational studies and some in vitro studies, suggesting a potential risk of mitogenicity with the administration of glargine, have caused some alarm among the medical community. Until now, there are no data to refute or confirm this risk and, therefore, evaluation of the existing data is crucial to obtain objective information. 相似文献
79.
Quantitative studies were conducted to evaluate the efficiency of the slit sampler in collecting airborne Serratia marcescens and Bacillus subtilis var. niger, and to compare it with the collecting efficiency of the all-glass impinger AGI-30. The slit sampler was approximately 50% less efficient than the AGI-30. This ratio remained the same whether liquid or dry cultures were disseminated when the sample was taken at 2 min of aerosol cloud life. At 30 min of aerosol cloud life, this ratio was approximately 30% for B. subtilis var. niger. S. marcescens recoveries by the slit sampler were, however, only 17% lower than the AGI-30 at 30 min of cloud age, indicating a possible interaction involving the more labile vegetative cells, aerosol age, and method of collection. 相似文献
80.
Aina Garcia-Raventós Antonio Muñoz-Mérida Oriol Lapiedra Mar Unzeta Mariona Ferrandiz-Rovira Daniel Sol 《Molecular ecology resources》2023,23(8):1905-1913
Single-nucleotide polymorphism (SNP) analysis is a powerful tool for population genetics, pedigree reconstruction and phenotypic trait mapping. However, the untapped potential of SNP markers to discriminate the sex of individuals in species with reduced sexual dimorphism or of individuals during immature stages remains a largely unexplored avenue. Here, we developed a novel protocol for molecular sexing of birds based on the detection of unique Z- and W-linked SNP markers. Our method is based on the identification of two unique loci, one in each sexual chromosome. Individuals are considered males when they show no calls for the W-linked SNP and are heterozygous or homozygous for the Z-linked SNP, while females exhibit both Z- and W-linked SNP calls. We validated the method in the Jackdaw (Corvus monedula). The reduced sexual dimorphism in this species makes it difficult to identify the sex of individuals in the wild. We assessed the reliability of the method using 36 individuals of known sex and found that their sex was correctly assigned in 100% of cases. The sex-linked markers also proved to be widely applicable for discriminating males and females from a sample of 927 genotyped individuals at different maturity stages, with an accuracy of 99.5%. Since SNP markers are increasingly used in quantitative genetic analyses of wild populations, the approach we propose has great potential to be integrated into broader genetic research programmes without the need for additional sexing techniques. 相似文献