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781.
Magdalena Jedrzejczak Iwona Szatkowska 《In vitro cellular & developmental biology. Animal》2014,50(5):389-398
In the present study, the analysis of epithelial cells derived from various sources was undertaken, beginning from the mammary gland tissue through the primary cultures and their subsequent passages. The objective of the study was the comparative analysis of the stage in which the epithelial cells obtained from individuals in different lactation cycles and disparate phases of cell culture growth are the most suitable for morphological research and analysis of gene expression activity. The cultures of primary bovine mammary epithelial cells and passages were identified morphologically using immunocytochemical methods. After positive identification, real-time PCRs were performed for the analysis of the expression level of casein genes, whey protein genes, and butyrophilin gene. The most stable reference genes in real-time PCRs for the mammary gland tissue and cell cultures were also determined. Of the reference genes, the UXT and GAPDH genes appeared to be the most stable ones for the mammary gland tissue samples and epithelial cell cultures. The results obtained allowed concluding that the mammary gland samples collected from heifers constituted the most effective material for the initiation of primary cultures. The primary cultures formed characteristic for the mammary gland tissue dome structures, which images were obtained using confocal microscopy. The highest levels of expression of the CSN1S1, CSN1S2, CSN2, and CSN3 genes were detected in primary cultures. The levels of expression of whey protein genes (LALBA and BGL) were highest in the second passage. The most abundant expression of the BTN1A1 gene was observed in primary cultures and the third passage. On the basis of the whole experiment, it can be concluded that primary cultures and cells of the second passage derived from heifer individuals appeared to be the best materials for the analysis of mammary gland function and gene expression activity. 相似文献
782.
Iwona Żur Ewa Dubas Elżbieta Golemiec Magdalena Szechyńska-Hebda Gabriela Gołębiowska Maria Wędzony 《Plant cell reports》2009,28(8):1279-1287
Isolated microspore cultures of two spring triticale (x Triticosecale Wittm.) cultivars were used to examine the effect of various stress treatments (either high—32°C or low—5°C temperature with
or without nitrogen/carbohydrate starvation) applied to excised anthers on the effectiveness of microspore embryogenesis induction.
To quantify the effects of pretreatment conditions, the activity of antioxidative enzymes (catalase, peroxidase and superoxide
dismutase) together with respiration rate and heat emission were measured. It was observed that heat shock treatment applied
as the only one stress factor increased the activity of antioxidative enzymes which suggests intensive generation of reactive
oxygen species. Such pretreatment effectively triggered microspore reprogramming but drastically decreased microspore viability.
After low temperature treatment, the activity of antioxidative enzymes was similar to the control subjected only with the
stress originated from the transfer to in vitro culture conditions. This pretreatment decreased the number of microspores
entering embryogenesis but sustained cell viability and this effect prevailed in the final estimation of microspore embryogenesis
effectiveness. For both, low- and high-temperature treatments, interaction with starvation stress was beneficial increasing
microspore viability (at 5°C) or efficiency of embryogenesis induction (at 32°C). The latter treatment significantly reduced
cell metabolic activity. Physiological background of these effects seems to be different and some hypothetical explanations
have been discussed. Received data indicate that in triticale, anther preculture conditions could generate oxidative stress
and change the cell metabolic activity which could next be reflected in the cell viability and the efficiency of microspore
embryogenesis. 相似文献
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Iwona Błaszczyk Ewa Birkner Sławomir Kasperczyk 《Biological trace element research》2011,139(3):325-331
Oxidative stress is a common mechanism by which chemical toxicity can occur in the liver. The aim of the studies conducted
has been to determine what influence the administration of methionine during intoxication with sodium fluoride may have upon
the selected enzymes of the antioxidative system in rat liver. The experiment was carried out on Wistar FL rats (adult females)
that, for 35 days, were administered distilled water, NaF, or NaF with methionine (doses: 10 mg NaF/kg bw/day, 10 mg Met/kg
bw/day). The influence of administered NaF and Met was examined by analyzing the activity of the antioxidative enzymes: superoxide
dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione transferase in the liver. The results
suggest that fluoride reduces the efficiency of the enzymatic antioxidative system in the liver. Administration of methionine
during intoxication with sodium fluoride does not have an advantageous influence upon the activity of superoxide dismutase,
catalase, reductase, and glutathione transferase in the liver. The slight increase of the activity of glutathione peroxidase
after administration of methionine may indicate its protective influence upon that enzyme. 相似文献
785.
Ewa Dubas Gabriela Golebiowska Iwona Zur Maria Wedzony 《Acta Physiologiae Plantarum》2011,33(2):529-537
According to regular reports, one of the most serious diseases of winter cereal and grass varieties in moderate and cold climatic
areas is pink snow mould caused by Microdochium nivale. Currently, the resistance of the economically important cereal species as triticale is not satisfactory. Moreover, there
is no efficient strategy of protection against this pathogen and the understanding of plant resistance mechanisms is rather
poor. Presented paper for the first time shows the cytological analysis of M. nivale infection in model triticale varieties by the use of fluorescent and light microscopy in combination with fluorescent dyes
and hydrogen peroxide staining. Both, the infection level and the dynamic of the process varied for tested genotypes confirming
the field and laboratory data of their different resistance to this pathogen. Moreover, our analysis showed that in both cultivars
cold-hardening of seedlings delayed the mycelium growth. In both cultivars, hyphal walls and fungal penetration sites were
visualized in crowns, leaf sheaths and leaves of hardened and non-hardened inoculated seedlings. For the first time the presence
of the haustoria produced by M. nivale was confirmed in those tissues. Single infection hyphae usually penetrated into the host tissues via stomatal apparatuses
were accompanied by the efflux of hydrogen peroxide. The data show a great potential of fluorescence techniques in studying
the host plant–pathogen interactions providing a better insight into plant defence reactions that may allow elaboration of
the efficient breeding strategies aimed at increasing resistance to this pathogenic fungus. 相似文献
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Keith A. Grimaldi Ben van Ommen Jose M. Ordovas Laurence D. Parnell John C. Mathers Igor Bendik Lorraine Brennan Carlos Celis-Morales Elisa Cirillo Hannelore Daniel Brenda de Kok Ahmed El-Sohemy Susan J. Fairweather-Tait Rosalind Fallaize Michael Fenech Lynnette R. Ferguson Eileen R. Gibney Mike Gibney Ingrid M. F. Gjelstad Jim Kaput Anette S. Karlsen Silvia Kolossa Julie Lovegrove Anna L. Macready Cyril F. M. Marsaux J. Alfredo Martinez Fermin Milagro Santiago Navas-Carretero Helen M. Roche Wim H. M. Saris Iwona Traczyk Henk van Kranen Lars Verschuren Fabio Virgili Peter Weber Jildau Bouwman 《Genes & nutrition》2017,12(1):35
Nutrigenetic research examines the effects of inter-individual differences in genotype on responses to nutrients and other food components, in the context of health and of nutrient requirements. A practical application of nutrigenetics is the use of personal genetic information to guide recommendations for dietary choices that are more efficacious at the individual or genetic subgroup level relative to generic dietary advice. Nutrigenetics is unregulated, with no defined standards, beyond some commercially adopted codes of practice. Only a few official nutrition-related professional bodies have embraced the subject, and, consequently, there is a lack of educational resources or guidance for implementation of the outcomes of nutrigenetic research. To avoid misuse and to protect the public, personalised nutrigenetic advice and information should be based on clear evidence of validity grounded in a careful and defensible interpretation of outcomes from nutrigenetic research studies. Evidence requirements are clearly stated and assessed within the context of state-of-the-art ‘evidence-based nutrition’. We have developed and present here a draft framework that can be used to assess the strength of the evidence for scientific validity of nutrigenetic knowledge and whether ‘actionable’. In addition, we propose that this framework be used as the basis for developing transparent and scientifically sound advice to the public based on nutrigenetic tests. We feel that although this area is still in its infancy, minimal guidelines are required. Though these guidelines are based on semi-quantitative data, they should stimulate debate on their utility. This framework will be revised biennially, as knowledge on the subject increases. 相似文献