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61.
Díaz López E A Morales Ruíz EJ Vargas Ramírez P Hernández Herrera RC Reséndiz Melgar I Brena Hernández JM Loeza Corte 《Phyton》2015,84(2):319-330
The effect of six phosphorus levels (0, 40, 80, 120, 160 and 200 kg/ha) on the duration of cumulative leaf area, biomass and agronomic yield was determined in the maize cultivars: Amarillo Almoloya, Cacahuacintle and Condor in 2010 and 2011. Such cultivars were sown in the Cerrillo Piedras Blancas Mexico. A completely randomized complete block design with factorial arrangement was utilized. High phosphorus levels (120, 160 and 200 kg/ha) positively affected the duration of cumulative leaf area; greatest values were obtained in Cacahuacintle. A greater duration of accumulated leaf area contributes to determine high values of biomass accumulation and grain yield in this cultivar. Leaf area duration appeared to be a useful tool for evaluating different genotypes in a given environment. 相似文献
62.
Using a calmodulin (CaM) cDNA as a probe in northern analyses, transgenic tomato plants that overexpress the prosystemin gene were found to express increased levels of CaM mRNA and protein in leaves compared to wild-type plants. These transgenic plants have been reported previously to express several wound-inducible defense-related genes in the absence of wounding. Calmodulin mRNA and protein levels were found to increase in leaves of young wild-type tomato plants after wounding, or treatment with systemin, methyl jasmonate, or linolenic acid. CaM mRNA appeared within 0.5 h after wounding or supplying young tomato plants with systemin, and peaked at 1 h. The timing of CaM gene expression is similar to the expression of the wound- or systemin-induced lipoxygenase and prosystemin genes, signal pathway genes whose expression have been reported to begin at 0.5–1 h after wounding and 1–2 h earlier than the genes coding for defensive proteinase inhibitor genes. The similarities in timing between the synthesis of CaM mRNA and the mRNAs for signal pathway components suggests that CaM gene expression may be associated with the signaling cascade that activates defensive genes in response to wounding. 相似文献
63.
Dexamethasone induces gelsolin synthesis and altered morphology in L929 cells 总被引:1,自引:1,他引:0 下载免费PDF全文
When L929 cells are exposed to 5 μg/ml dexamethasone, synthesis of a 90,000 M(r) polypeptide is induced within 12 h. Flattening of the cells begins at about this time and progresses to become quite prominent after 48 h of exposure. Two-dimensional PAGE and partial proteolytic fingerprints identify the 90,000 M(r) polypeptide as gelsolin, a Ca(++)-dependent inhibitor of actin polymerization. Thus, this system provides evidence that gelsolin may have a role in regulating cell shape in response to physiological agents such as glucocorticoids. 相似文献
64.
We propose a new measure of synchronization of multichannel ictal and interictal EEG signals. The measure is based on the
residual covariance matrix of a multichannel autoregressive model. A major advantage of this measure is its ability to be
interpreted both in the framework of stochastic and deterministic models. A preliminary analysis of EEG data from three patients
using this measure documents the expected increased synchronization during ictal periods but also reveals that increased synchrony
persists for prolonged periods (up to 2 h or more) in the postictal period.
Received: 20 July 1997 / Accepted in revised form: 26 January 1999 相似文献
65.
Stefan Richter Rudi Loesel Günter Purschke Andreas Schmidt-Rhaesa Gerhard Scholtz Thomas Stach Lars Vogt Andreas Wanninger Georg Brenneis Carmen Döring Simone Faller Martin Fritsch Peter Grobe Carsten M Heuer Sabrina Kaul Ole S Møller Carsten HG Müller Verena Rieger Birgen H Rothe Martin EJ Stegner Steffen Harzsch 《Frontiers in zoology》2010,7(1):1-49
66.
Surface area measurement is a common component of benthic research, especially in the quantification of chlorophyll. Multiple
techniques are available and 10 are described: artificial substrates, area-specific sampling, geometric approximation, stone
shape equations, foil wrapping, grids, stamps, wetted layer, particle layer, and planar area measurement. A literature search
of 130 papers indicated the most common methods: using artificial substrates of known area, subsampling a specific area using
a template or sampler, measuring stone dimensions and using an equation to derive area, and using the weight of foil wrapped
on stones. Methods were compared using spheres of known area, smooth and rough granite stones, and plastic macrophytes. Most
methods produced highly correlated measurements and accurately estimated surface area. The wetted layer method was sensitive
to stone roughness and plant complexity, but may overestimate the area of complex surfaces. Replication of one method by 10
biologists indicated that individual differences in technique can affect surface area values. Factors to consider in choosing
an appropriate method include ease of use, characteristics of the substrates (e.g., porosity and flexibility), fineness of
scale in measuring area, and whether methods must be field-based or can include laboratory techniques. 相似文献
67.
Background
We consider the potential for infection to spread in a farm population from the primary outbreak farm via livestock movements prior to disease detection. We analyse how this depends on the time of the year infection occurs, the species transmitting, the length of infectious period on the primary outbreak farm, location of the primary outbreak, and whether a livestock market becomes involved. We consider short infectious periods of 1 week, 2 weeks and 4 weeks, characteristic of acute contagious livestock diseases. The analysis is based on farms in Scotland from 1 January 2003 to 31 July 2007.Results
The proportion of primary outbreaks from which an acute contagious disease would spread via movement of livestock is generally low, but exhibits distinct annual cyclicity with peaks in May and August. The distance that livestock are moved varies similarly: at the time of the year when the potential for spread via movements is highest, the geographical spread via movements is largest. The seasonal patterns for cattle differ from those for sheep whilst there is no obvious seasonality for pigs. When spread via movements does occur, there is a high risk of infection reaching a livestock market; infection of markets can amplify disease spread. The proportion of primary outbreaks that would spread infection via livestock movements varies significantly between geographical regions.Conclusions
In this paper we introduce a set-up for analysis of movement data that allows for a generalized assessment of the risk associated with infection spreading from a primary outbreak farm via livestock movements, applying this to Scotland, we assess how this risk depends upon the time of the year, species transmitting, location of the farm and other factors. 相似文献68.
A sample of fixed bacterial cells was examined by immunofluorescence microscopy using an Alexa 488 conjugated secondary antibody for visualization. Excitation using visible light confirmed the expected photostability of this fluorophore; however, when using 2-photon excitation, Alexa 488 was rapidly and substantially photobleached. The unexpected instability of Alexa 488 under certain conditions may have deleterious consequences if not anticipated and accommodated in experimental protocols. 相似文献
69.
70.
Veera Kainulainen Yurui Tang Thomas Spillmann Susanne Kilpinen Justus Reunanen Per EJ Saris Reetta Satokari 《BMC microbiology》2015,15(1)