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81.
Lissette Valverde-Cerdas Magaly Dufour Victor M. Villalobos 《In vitro cellular & developmental biology. Plant》1997,33(1):38-42
Summary Plants were obtained via organogenesis from hypocotyl explants of Pithecellobium saman (Jacq.) Benth. (raintree) on Murashige and Skoog (1962) medium supplemented with N6-benzyladenine (BA). Adventitious bud induction was affected by mineral salts and benzyladenine concentrations, explant age,
position of explant on the medium, and BA exposure time. The best results were obtained with explants cultured on half-strength
MS medium containing 26.6 μM BA, with explants of 5 and 10 d after germination placed horizontally and a 7 d-exposure period to BA. The proximal and intermediate
section of hypocotyls showed the highest organogenic response. Bud development and shoot elongation was promoted by increased
concentrations of activated charcoal in the culture medium. Gibberellic acid had no effect on shoot development. Rooting percentages
decreased when shoots were exposed for more than 24 h to indole-3-butyric acid (IBA). Maximum rooting was obtained with 369.0
μM IBA. The aerial and root systems of greenhouse plantlets were similar to those of seedlings. 相似文献
82.
Maria D. Hurtado Andres Acosta Paola P. Riveros Bruce J. Baum Kirill Ukhanov Alicia R. Brown Cedrick D. Dotson Herbert Herzog Sergei Zolotukhin 《PloS one》2012,7(9)
Peptide hormones and their cognate receptors belonging to neuropeptide Y (NPY) family mediate diverse biological functions in a number of tissues. Recently, we discovered the presence of the gut satiation peptide YY (PYY) in saliva of mice and humans and defined its role in the regulation of food intake and body weight maintenance. Here we report the systematic analysis of expression patterns of all NPY receptors (Rs), Y1R, Y2R, Y4R, and Y5R in lingual epithelia in mice. Using four independent assays, immunohistochemistry, in situ hybridization, immunocytochemistry and RT PCR, we show that the morphologically different layers of the keratinized stratified epithelium of the dorsal layer of the tongue express Y receptors in a very distinctive yet overlapping pattern. In particular, the monolayer of basal progenitor cells expresses both Y1 and Y2 receptors. Y1Rs are present in the parabasal prickle cell layer and the granular layer, while differentiated keratinocytes display abundant Y5Rs. Y4Rs are expressed substantially in the neuronal fibers innervating the lamina propria and mechanoreceptors. Basal epithelial cells positive for Y2Rs respond robustly to PYY3–36 by increasing intracellular Ca2+ suggesting their possible functional interaction with salivary PYY. In taste buds of the circumvallate papillae, some taste receptor cells (TRCs) express YRs localized primarily at the apical domain, indicative of their potential role in taste perception. Some of the YR-positive TRCs are co-localized with neuronal cell adhesion molecule (NCAM), suggesting that these TRCs may have synaptic contacts with nerve terminals. In summary, we show that all YRs are abundantly expressed in multiple lingual cell types, including epithelial progenitors, keratinocytes, neuronal dendrites and TRCs. These results suggest that these receptors may be involved in the mediation of a wide variety of functions, including proliferation, differentiation, motility, taste perception and satiation. 相似文献
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The aim of this study was to examine brain responses, in particular functional connectivity, to different visual stimuli depicting familiar biological motions. Ten subjects actively observed familiar biological motions embedded in point-light and video displays. Electroencephalograms were recorded from 64 electrodes. Activity was considered in three frequency bands (4-8 Hz, 8-10 Hz, and 10-13 Hz) using a non-linear measure of functional connectivity. In the 4-8 Hz and 8-10 Hz frequency bands, functional connectivity for the SMA was greater during the observation of biological motions presented in a point-light display compared to the observation of motions presented in a video display. The reverse was observed for the 4-8 Hz frequency band for the left temporal area. Explanations related to: (i) the task demands (i.e., attention and mental effort), (ii) the role(s) of theta and alpha oscillations in cognitive processes, and (iii) the function(s) of cortical areas are discussed. It has been suggested that attention was required to process human biological motions under unfamiliar viewing conditions such as point-light display. 相似文献
85.
Nicole Mongilardi Víctor Montori Alejandro Riveros Antonio Bernabé-Ortiz Javier Loza Germán Málaga 《PloS one》2013,8(3)
Background
Little is known about the extent to which Peruvian physicians seek to involve patients in shared decision making, or about the variation in these efforts across different settings.Objective
To measure the extent to which Peruvian clinicians involve their patients in decision making and to explore the differences between clinicians’ behavior in private vs. public practice.Design
Videographic analysis.Participants and Setting
Seven academic physicians who provided care to patients in a public and a private setting participate in this study. All the encounters in both settings were filmed on one random day of February 2012. Approach: Two raters, working independently and in duplicate used the 12-item OPTION scale to quantify the extent of physician effort to involve patients in shared decision making (with 0 indicating no effort and 100 maximum possible effort) in 58 video recordings of usual clinical encounters in private and public practice.Results
The mean OPTION score was 14.3 (SD 7.0). Although the OPTION score in the private setting (mean 16.5, SD 7.3) was higher than in the public setting (mean 12.3 SD 6.1) this difference was not statistically significant (p = .09).Conclusion
Peruvian academic physicians in this convenience sample barely sought to involve their patients in shared decision making. Additional studies are required to confirm these results which suggest that patient-centered care remains an unfulfilled promise and a source of inequity within and across the private and the public sectors in Peru. 相似文献86.
Marie‐Eve Val Sean P. Kennedy Alfonso J. Soler‐Bistué Valérie Barbe Christiane Bouchier Magaly Ducos‐Galand Ole Skovgaard Didier Mazel 《Molecular microbiology》2014,91(4):665-678
Dam methylates GATC sequences in γ‐proteobacteria genomes, regulating several cellular functions including replication. In Vibrio cholerae, which has two chromosomes, Dam is essential for viability, owing to its role in chr2 replication initiation. In this study, we isolated spontaneous mutants of V. cholerae that were able to survive the deletion of dam. In these mutants, homologous recombination and chromosome dimer resolution are essential, unless DNA mismatch repair is inactivated. Furthermore, the initiator of chr2 replication, RctB, is no longer required. We show that, instead, replication of chr2 is insured by spontaneous fusion with chr1 and piggybacking its replication machinery. We report that natural fusion of chr1 and chr2 occurred by two distinct recombination pathways: homologous recombination between repeated IS elements and site‐specific recombination between dif sites. Lastly, we observed a preferential fusion of the two chromosomes in their terminus of replication. 相似文献
87.
Argaw Ambelu Seblework Mekonen Magaly Koch Taffere Addis Pieter Boets Gert Everaert Peter Goethals 《PloS one》2014,9(11)
Blackflies are important macroinvertebrate groups from a public health as well as ecological point of view. Determining the biological and environmental factors favouring or inhibiting the existence of blackflies could facilitate biomonitoring of rivers as well as control of disease vectors. The combined use of different predictive modelling techniques is known to improve identification of presence/absence and abundance of taxa in a given habitat. This approach enables better identification of the suitable habitat conditions or environmental constraints of a given taxon. Simuliidae larvae are important biological indicators as they are abundant in tropical aquatic ecosystems. Some of the blackfly groups are also important disease vectors in poor tropical countries. Our investigations aim to establish a combination of models able to identify the environmental factors and macroinvertebrate organisms that are favourable or inhibiting blackfly larvae existence in aquatic ecosystems. The models developed using macroinvertebrate predictors showed better performance than those based on environmental predictors. The identified environmental and macroinvertebrate parameters can be used to determine the distribution of blackflies, which in turn can help control river blindness in endemic tropical places. Through a combination of modelling techniques, a reliable method has been developed that explains environmental and biological relationships with the target organism, and, thus, can serve as a decision support tool for ecological management strategies. 相似文献
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