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91.
GMDD: a database of GMO detection methods 总被引:1,自引:0,他引:1
Wei Dong Litao Yang Kailin Shen Banghyun Kim Gijs A Kleter Hans JP Marvin Rong Guo Wanqi Liang Dabing Zhang 《BMC bioinformatics》2008,9(1):260
Background
Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed. 相似文献92.
93.
Interactions of maize and Italian ryegrass in a living mulch system: (2) Nitrogen and water dynamics
Plant and Soil - Water and nitrogen availability may limit the growth of the main crop competing with a cover crop in a living mulch system. Some aspects of the dynamics of water (soil water... 相似文献
94.
Ten years of free-air CO2 enrichment altered the mobilization of N from soil in Lolium perenne L. swards 总被引:2,自引:0,他引:2
Manuel K. Schneider reas Lüscher Michael Richter Urs Aeschlimann Ueli A. Hartwig Herbert Blum Emmanuel Frossard Josef Nösberger 《Global Change Biology》2004,10(8):1377-1388
Effects of free‐air carbon dioxide enrichment (FACE, 60 Pa pCO2) on plant growth as compared with ambient pCO2 (36 Pa) were studied in swards of Lolium perenne L. (perennial ryegrass) at two levels of N fertilization (14 and 56 g m?2 a?1) from 1993 to 2002. The objectives were to determine how plant growth responded to the availability of C and N in the long term and how the supply of N to the plant from the two sources of N in the soil, soil organic matter (SOM) and mineral fertilizer, varied over time. In three field experiments, 15N‐labelled fertilizer was used to distinguish the sources of available N. In 1993, harvestable biomass under elevated pCO2 was 7% higher than under ambient pCO2. This relative pCO2 response increased to 32% in 2002 at high N, but remained low at low N. Between 1993 and 2002, the proportions and amounts of N in harvestable biomass derived from SOM (excluding remobilized fertilizer) were, at high N, increasingly higher at elevated pCO2 than at ambient pCO2. Two factorial experiments confirmed that at high N, but not at low N, a higher proportion of N in harvestable biomass was derived from soil (including remobilized fertilizer) following 7 and 9 years of elevated pCO2, when compared with ambient pCO2. It is suggested that N availability in the soil initially limited the pCO2 response of harvestable biomass. At high N, the limitation of plant growth decreased over time as a result of the stimulated mobilization of N from soil, especially from SOM. Consequently, harvestable biomass increasingly responded to elevated pCO2. The underlying mechanisms which contributed to the increased mobilization of N from SOM under elevated pCO2 are discussed. This study demonstrated that there are feedback mechanisms in the soil which are only revealed during long‐term field experiments. Such investigations are thus, a prerequisite for understanding the responses of ecosystems to elevated pCO2 and N supply. 相似文献
95.
Background
Comparative genomic data among organisms allow the reconstruction of their phylogenies and evolutionary time scales. Molecular timings have been recently used to suggest that environmental global change have shaped the evolutionary history of diverse terrestrial organisms. Living xenarthrans (armadillos, anteaters and sloths) constitute an ideal model for studying the influence of past environmental changes on species diversification. Indeed, extant xenarthran species are relicts from an evolutionary radiation enhanced by their isolation in South America during the Tertiary era, a period for which major climate variations and tectonic events are relatively well documented. 相似文献96.
JP Herv s J. Martí -Clú a A. Mu oz-Garcí a MC Santa-Cruz 《Biotechnic & histochemistry》2002,77(1):27-35
We have optimised an indirect immunoperoxidase technique demonstrating bromodeoxyuridine (BrdU) incorporation into dividing cells for cerebellar tissue sections of four-day-old rats injected with this marker. This permits confident identification of granule-cell precursors engaged in DNA synthesis in the external granular layer of the developing cerebellum. Preservation of BrdU immunoreactivity is attained using methanol/acetic acid fixation and different pretreatments before immunostaining, while unlabeled nuclei can be recognized clearly after Feulgen or hematoxylin counterstaining. We established conditions to ensure satisfactory BrdU uptake without affecting cell-cycle progression during the postlabeling time period. The dose of BrdU employed provides saturation S-phase labeling from at least 1 h after BrdU delivery. Various kinetic parameters and phase durations have been determined in experiments involving a single injection or cumulative labeling sequences, and the cycle time was calculated based on two models of generative behavior: steady-state and exponential growth. The working hypothesis of steadystate kinetics can be adopted successfully if the existence of neuroblasts with different proliferation rates is taken into account. 相似文献
97.
Congenital insensitivity to pain with anhidrosis: novel mutations in the TRKA (NTRK1) gene encoding a high-affinity receptor for nerve growth factor. 总被引:3,自引:0,他引:3
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S Mardy Y Miura F Endo I Matsuda L Sztriha P Frossard A Moosa E A Ismail A Macaya G Andria E Toscano W Gibson G E Graham Y Indo 《American journal of human genetics》1999,64(6):1570-1579
Congenital insensitivity to pain with anhidrosis (CIPA) is characterized by recurrent episodes of unexplained fever, anhidrosis (inability to sweat), absence of reaction to noxious stimuli, self-mutilating behavior, and mental retardation. Human TRKA encodes a high-affinity tyrosine kinase receptor for nerve growth factor (NGF), a member of the neurotrophin family that induces neurite outgrowth and promotes survival of embryonic sensory and sympathetic neurons. We have recently demonstrated that TRKA is responsible for CIPA by identifying three mutations in a region encoding the intracellular tyrosine kinase domain of TRKA in one Ecuadorian and three Japanese families. We have developed a comprehensive strategy to screen for TRKA mutations, on the basis of the gene's structure and organization. Here we report 11 novel mutations, in seven affected families. These are six missense mutations, two frameshift mutations, one nonsense mutation, and two splice-site mutations. Mendelian inheritance of the mutations is confirmed in six families for which parent samples are available. Two mutations are linked, on the same chromosome, to Arg85Ser and to His598Tyr;Gly607Val, hence, they probably represent double and triple mutations. The mutations are distributed in an extracellular domain, involved in NGF binding, as well as the intracellular signal-transduction domain. These data suggest that TRKA defects cause CIPA in various ethnic groups. 相似文献
98.
Dimorphic markers for the human apolipoprotein CII gene locus 总被引:2,自引:0,他引:2
Two restriction-site polymorphisms (RSP) have been detected when using a human apolipoprotein CII (apoCII) cDNA clone as a hybridization probe. These include a BanI and a TaqI RSP. Frequencies of the more common allele have been determined in a German population of 100 individuals and are 0.66 (BanI RSP) and 0.56 (TaqI RSP). Corresponding polymorphic information content (PIC) values are 0.36 and 0.37 for individual sites, and 0.58 for the BanI-TaqI pair of sites, making this locus a very informative (PIC-rich) marker for this region of chromosome 19. Haplotype studies also indicate the presence of allelic association (linkage disequilibrium) at the human apoCII gene locus. 相似文献
99.
Castagnone-Sereno P; Semblat JP; Leroy F; Abad P 《Molecular biology and evolution》1998,15(9):1115-1122
A highly abundant satellite DNA comprising 20% of the Meloidogyne fallax
(Nematoda, Tylenchida) genome was cloned and sequenced. The satellite
monomer is 173 bp long and has a high A + T content of 72.3%, with frequent
runs of A's and T's. The sequence variability of the monomers is 2.7%,
mainly due to random distribution of single-point mutations. A search for
evidence of internal repeated subunits in the monomer sequence revealed a
6-bp motif (AAATTT) for which five degenerated repeats, differing by just a
single base pair, could be identified. Pairwise comparison of the M. fallax
satellite with those from the sympatric species Meloidogyne chitwoodi and
Meloidogyne hapla revealed a high sequence similarity (68.39%) with one
satellite DNA subfamily in M. chitwoodi, which indicated an unexpected
close relationship between them. Given the high copy number and the extreme
sequence homogeneity among monomeric units, it may be assumed that the
satellite DNA of M. fallax could have evolved through some recent and
extensive amplification burst in the nematode genome. In this case, its
relatively short life would not yet have allowed the accumulation of random
mutations in independent amplified repeats. Considering the morphological
resemblance between the two species and their ability to produce
interspecific fertile hybrids under controlled conditions, these results
indicate that M. fallax may share a common ancestor with M. chitwoodi, from
which it could have diverged recently. All these data suggest that M.
fallax could be the result of a recent speciation process and show that
Meloidogyne satellite DNAs may be of interest to resolve phylogenetic
relationships among closely related species from this genus.
相似文献
100.
High mineral contents explain the low construction cost of leaves, stems and fruits of tomato plants 总被引:2,自引:1,他引:1
The construction cost of plant tissues is used in crop models to convert
the products of photosynthesis into biomass. As for other greenhouse crops,
tomato tissues are specific in that they have a high mineral content. The
consequences of this accumulation of minerals on the construction cost of
the tissues and the possible interactions with the physiological age of the
organs and with the CO2 concentration in the atmosphere was examined. For
that purpose, three methods of estimating the construction cost were used
and compared. Large quantities of minerals accumulated in the tissues of
tomato plants (ranging from 0.05 in fruits to 0.26 g
g-1 DM in leaves). The subsequent dilution of the
organic matter explained why the estimated construction cost of the dry
matter (organic matter + minerals) was fairly low in comparison to that of
other crops species. The construction cost was higher in fruits than in
vegetative organs, partly because of a lower mineral content. It decreased
by 7-12% from top to bottom of the canopy, following the increase in the
physiological age of the tissues. This ontogenic drift was partly explained
by the accumulation of minerals in the older organs. In the conditions of
CO2 enrichment of a commercial greenhouse, no effect of CO2 concentration
on the mineral content and on the construction cost of tissues was
observed. Such a variability of the construction cost of tomato plant
tissues due to the accumulation of minerals or to the ontogeny questions
the use of standard values in crop models.Key words: Lycopersicon
esculentum Mill., construction cost, heat of combustion,
elemental composition, mineral content.
相似文献