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21.
Ján Košuth Denisa Hrehorová Mariusz Jaskolski Eva Čellárová 《Plant Cell, Tissue and Organ Culture》2013,114(2):207-216
The phenolic oxidative coupling protein (Hyp-1) with proposed activity in the biosynthesis of hypericin in Hypericum perforatum shares about 50 % sequence similarity with Bet.v.1-like/PR-10 proteins. In our previous study, we showed that this protein is not a limiting factor in hypericin biosynthesis. To ascertain the role of Hyp-1 in defense mechanisms, we have analyzed some structural features of the hyp-1 gene in 14 Hypericum species with different abilities to synthesise hypericin. We show that the hyp-1 gene possesses characteristics typical for genes encoding plant PR-10 proteins. The coding sequence of the hyp-1 gene is interrupted by a single 86- to 125-bp intron localised strictly in codon 62, which is a typical feature of the dicot PR-10 subfamily. The localisation of the intron is conserved in all 14 tested Hypericum species indicating a common evolutionary history with genes encoding PR-10 proteins. In addition, we report that the hyp-1 gene exhibits a similar response to stress conditions as the PR-10 proteins encoding genes. Following either wounding or infection by Agrobacterium tumefaciens, all analysed Hypericum species exhibited rapid and significant upregulation of hyp-1 gene expression; this was particularly observed in hypericin-producing species. On the other hand, in the presence of high levels of abscisic acid, different levels of gene expression were observed. 相似文献
22.
Stephana Carelli Toniella Giallongo Cristina Viaggi Zuzana Gombalova Elisa Latorre Massimiliano Mazza Francesca Vaglini Anna Maria Di Giulio Alfredo Gorio 《ASN neuro》2016,8(5)
Erythropoietin-releasing neural precursor cells (Er-NPCs) are a subclass of subventricular zone-derived neural progenitors, capable of surviving for 6 hr after death of donor. They present higher neural differentiation. Here, Er-NPCs were studied in animal model of Parkinson’s disease. Dopaminergic degeneration was caused by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intraperitoneal administration in C57BL/6 mice. The loss of function was evaluated by specific behavioral tests. Er-NPCs (2.5 × 105) expressing the green fluorescent protein were administered by stereotaxic injection unilaterally in the left striatum. At the end of observational research period (2 weeks), most of the transplanted Er-NPCs were located in the striatum, while several had migrated ventrally and caudally from the injection site, up to ipsilateral and contralateral substantia nigra. Most of transplanted cells had differentiated into dopaminergic, cholinergic, or GABAergic neurons. Er-NPCs administration also promoted a rapid functional improvement that was already evident at the third day after cells administration. This was accompanied by enhanced survival of nigral neurons. These effects were likely promoted by Er-NPCs-released erythropoietin (EPO), since the injection of Er-NPCs in association with anti-EPO or anti-EPOR antibodies had completely neutralized the recovery of function. In addition, intrastriatal administration of recombinant EPO mimics the effects of Er-NPCs. We suggest that Er-NPCs, and cells with similar properties, may represent good candidates for cellular therapy in neurodegenerative disorders of this kind. 相似文献
23.
24.
Denisa Blažková 《Folia Geobotanica》1976,11(4):426-426
25.
Denisa Blažková 《Folia Geobotanica》1993,28(3):247-260
Grasslands were phytosociologically studied in the lowlands of North Korea. They are represented mainly by Lawns in parks and recreation centres. Two new plant communities were distinguished: the associationDigitario ciliaris-Zoysietum japonicae with many species of the C4 photosynthetic pathway, growing on open sunny habitats and the associationPlantagini asiaticae-Poetum pratensis consisting mostly of species with the C3 photosynthetic pathway and growing on half shaded or moist habitats. Real pastures and meadows are very rare in North Korea. They are analogous to the communities described from Japan. 相似文献
26.
27.
Ingrid Žitňanová Silvia Ranostajová Hana Sobotová Denisa Demelová Ivan Pecháň Zdeňka Ďuračková 《Biologia》2006,61(3):279-284
Recent studies have demonstrated that dietary plants are rich source of antioxidants and can contribute to the protection
from age-related diseases. The aim of our study was to determine the total antioxidant capacity of extracts from different
kinds of fruits and vegetables, and to examine their inhibitory effect on the oxidative damage to proteins in vitro. For determination of antioxidant capacity we used two direct methods. Among the food materials chosen for the present study,
blueberries and red beets gave the maximum antioxidant activity. The lowest activity was determined in pears and green beans.
Some extracts were more active in one method, while their activity was lower using the other method. To investigate inhibitory
effects of fruits and vegetables extracts on the oxidative damage to proteins in vitro, we induced the oxidative damage to plasma proteins by sodium hypochlorite leading to formation of carbonyl compounds detected
by spectrophotometric method. All extracts of fruits and vegetables showed inhibitory activity on the oxidative damage to
proteins with raspberries and leek as most effective. Results of this study will be useful as an aid for dietary choices to
increase antioxidant intake and will allow the investigation of the relation between dietary antioxidants and oxidative stress-induced
diseases. 相似文献
28.
The PERLA system in the Czech Republic: a multivariate approach for assessing the ecological status of running waters 总被引:4,自引:4,他引:0
Jiří Kokeš Světlana Zahrádková Denisa Němejcová Jan Hodovský Jiří Jarkovský Tomáš Soldán 《Hydrobiologia》2006,566(1):343-354
The assessment of running water quality has a long tradition in the Czech Republic, but in the past it focused on the evaluation
of organic pollution using the saprobic system. Considering the modern trends of stream ecological status evaluation in water
management a new assessment system named PERLA was developed. The system is a complex of biological methods of ecological
status assessment of running waters and connected activities in the Czech Republic. It involves 300 reference sites with respective
biotic and abiotic data and a prediction model using a newly developed software HOBENT. The model generally follows the published
mathematical principles of RIVPACS and represents the site specific and stressor non-specific approaches. The HOBENT software
allows the prediction of the target assemblage of benthic macroinvertebrates for any site based on a set of environmental
variables (latitude, longitude, distance from source, altitude, slope, catchment area, and stream order) which characterise
the site. The predicted assemblage can be compared with the fauna observed at the same site. The comparison makes it possible
to evaluate the extent of disturbance, expressed by index B. The model allows to evaluate spring, summer, and autumn seasonal
data of the majority of wadable streams in the Czech Republic. The practical application of the PERLA system has started in
2001. 相似文献
29.
Denisa Petrackova Jaroslav Vecer Jaroslava Svobodova Petr Herman 《The Journal of membrane biology》2010,233(1-3):73-83
We characterized physical and chemical properties of cell-membrane fragments from Bacillus subtilis 168 (trpC2) grown at pH 5.0, 7.0 and 8.5. Effects of long-term bacterial adaptation reflected in growth rates and in changes of the membrane lipid composition were correlated with lipid order and dynamics using time-resolved fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene. We demonstrate that the pH adaptation results in a modification of a fatty acid content of cellular membranes that significantly influences both the lipid-chain order and dynamics. For cultivation at acidic conditions, the lipid order increases and membrane dynamics decreases compared to pH 7.0. This results in rigid and ordered membranes. Cultivation at pH 8.5 causes slight membrane disordering. Instant pH changes induce qualitatively similar but smaller effects. Proton flux measurements performed on intact cells adapted to both pH 5.0 and 8.5 revealed lower cell-membrane permeability compared to bacteria cultivated at pH optimum. Our results indicate that both acidic and alkalic pH stress represent a permanent challenge for B. subtilis to keep a functional membrane state. The documented adaptation-induced adjustments of membrane properties could be an important part of mechanisms maintaining an optimal intracellular pH at a wide range of extracellular proton concentrations. 相似文献
30.
The clearance mechanism of chilled blood platelets 总被引:34,自引:0,他引:34
Hoffmeister KM Felbinger TW Falet H Denis CV Bergmeier W Mayadas TN von Andrian UH Wagner DD Stossel TP Hartwig JH 《Cell》2003,112(1):87-97
Platelet transfusion is a very common lifesaving medical procedure. Not widely known is the fact that platelets, unlike other blood cells, rapidly leave the circulation if refrigerated prior to transfusion. This peculiarity requires blood services to store platelets at room temperature, limiting platelet supplies for clinical needs. Here, we describe the mechanism of this clearance system, a longstanding mystery. Chilling platelets clusters their von Willebrand (vWf) receptors, eliciting recognition of mouse and human platelets by hepatic macrophage complement type 3 (CR3) receptors. CR3-expressing but not CR3-deficient mice exposed to cold rapidly decrease platelet counts. Cooling primes platelets for activation. We propose that platelets are thermosensors, primed at peripheral sites where most injuries occurred throughout evolution. Clearance prevents pathologic thrombosis by primed platelets. Chilled platelets bind vWf and function normally in vitro and ex vivo after transfusion into CR3-deficient mice. Therefore, GPIb modification might permit cold platelet storage. 相似文献