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61.
The present study was carried out in a phenological garden in central Italy that contains vegetative clones of shrubs and trees common to several international phenological gardens, such as Cornus sanguinea L.; Corylus avellana L.; Ligustrum vulgare L.; Robinia pseudoacacia L.; Salix acutifolia Willd. and Sambucus nigra L. Vegetative plant growth monitoring was carried out weekly using common international keys: BBCH07, bud break and leaf unfolding; BBCH19, young unfolded leaf; BBCH91, adult leaves; BBCH93, beginning of leaf colouring. The phenological dates thus obtained provide a model of the development for these different species in relation to the 15-year period of observation (1997–2011). From a meteorological point of view, temperature and precipitation trends were studied, with the highest anomalies during the study period recorded during the first 2 months of the year (January, February). There was relative invariance in the manifestation of the open bud phase and the contemporary advance of the young open leaves phase, particularly from 2006. This was accompanied by shortening of the leaf opening period, which appeared due to more rapid spring temperature increases over the last few years. The advance tendency of the BBCH91 phase showed adult leaves from the first summer weeks with fully green foliage monitored for a long time. Generally, the autumn leaf colouring phase tended to remain constant, with the exception of Salix acutifolia and Sambucus nigra, for which, on the other hand, the first leaf development phases appeared to be most likely influenced by the photoperiod.  相似文献   
62.
The aim of this study was to investigate the main climatic and biological trends related to olive flowering in central-southern Italy compared to those in Andalusia, Spain. Results since 1982 were compared for the two long-series monitoring areas of Cordoba and Perugia, and since 1992–1999 for the short-series areas. The relationship between climatic trends and the biological response of the olive, a widespread culture in the Mediterranean basin, were investigated. An aerobiological method involving capturing pollen released into the atmosphere was utilised as a bioindicator of flowering phenology. The study results confirm the strong relationship between flowering periods and spring temperature trends for the olive. Temperature during March, April and May was the parameter most related to flowering date in the study areas, particularly in Italy. In some cases we found a significant correlation between flowering and past autumn temperatures, probably due to their effect on floral bud dormancy induction, but this phenomenon appeared to be of minor importance in the studied areas. The phenological trend results show the continuous advance of flowering dates to the late 1990s, followed by a relatively stationary time series related to a short-term temperature fluctuation in the Mediterranean area. This latter period probably represents a mesoscale event forced by a macroscale event—the North Atlantic Oscillation. The results reveal that the trend towards increased temperatures, and the consequent flowering advance of some species, indicated some years ago is nowadays not as clear as was expected and should be confirmed over the next few years in the Mediterranean areas under investigation.  相似文献   
63.
Autophagy is a lysosome‐dependent degradation pathway essential to maintain cellular homeostasis. Therefore, either defective or excessive autophagy may be detrimental for cells and tissues. The past decade was characterized by significant advances in molecular dissection of stimulatory autophagy inputs; however, our understanding of the mechanisms that restrain autophagy is far from complete. Here, we describe a negative feedback mechanism that limits autophagosome biogenesis based on the selective autophagy‐mediated degradation of ATG13, a component of the ULK1 autophagy initiation complex. We demonstrate that the centrosomal protein OFD1 acts as bona fide autophagy receptor for ATG13 via direct interaction with the Atg8/LC3/GABARAP family of proteins. We also show that patients with Oral‐Facial‐Digital type I syndrome, caused by mutations in the OFD1 gene, display excessive autophagy and that genetic inhibition of autophagy in a mouse model of the disease, significantly ameliorates polycystic kidney, a clinical manifestation of the disorder. Collectively, our data report the discovery of an autophagy self‐regulated mechanism and implicate dysregulated autophagy in the pathogenesis of renal cystic disease in mammals.  相似文献   
64.
Objectives: Although emerging data suggest that zoledronic acid (Zol) may have different anti‐tumour activities against a broad range of cancers, its effects on lung cancer remain largely unknown. The aim of this study was to evaluate in vitro the anti‐tumoural and anti‐angiogenetic effect of zoledronic acid in non‐small‐cell lung cancer (NSCLC) cells. Material and methods: We treated A549 NSCLC cells with zoledronic acid to investigate survival, cell cycle activity, anti‐angiogenic activity and apoptotic responses to it. Results: We observed that highest Zol concentration (100 μm ) caused arrest in G1 phase of the cell cycle and also induced different percentages of apoptosis in presence (0.9% versus 4.4%) or absence (2.4% versus 28.5%) of serum (P = 0.0001). Zol concentration from 5 to 100 μm for 2 days induced significant concentration‐dependent cell death in adherent cells. Furthermore, Zol (10–100 μm ) induced dose‐dependent reduction both of mRNA and protein expression of VEGF associated with parallel decrease in VEGF secretion in the culture medium. Conclusion: Taken together, these results support a possible anti‐cancer and anti‐angiogenetic activity of Zol. Our data may not only provide a basis for the clinical use of this drug as preventive agent of bone metastases but also suggest that Zol deserves attention as an anti‐cancer agent in non‐small‐cell lung cancer.  相似文献   
65.
66.
Cyclospora cayetanensis is a coccidian parasite that causes protracted diarrheal illness in humans. C. cayetanensis is the only species of this genus thus far associated with human illness, although Cyclospora species from other primates have been named. The current method to detect the parasite uses a nested PCR assay to amplify a 294-bp region of the small subunit rRNA gene, followed by restriction fragment length polymorphism (RFLP) or DNA sequence analysis. Since the amplicons generated from C. cayetanensis and Eimeria species are the same size, the latter step is required to distinguish between these different species. The current PCR-RFLP protocol, however, cannot distinguish between C. cayetanensis and these new isolates. The differential identification of such pathogenic and nonpathogenic parasites is essential in assessing the risks to human health from microorganisms that may be potential contaminants in food and water sources. Therefore, to expand the utility of PCR to detect and identify these parasites in a multiplex assay, a series of genus- and species-specific forward primers were designed that are able to distinguish sites of limited sequence heterogeneity in the target gene. The most effective of these unique primers were those that identified single-nucleotide polymorphisms (SNPs) at the 3' end of the primer. Under more stringent annealing and elongation conditions, these SNP primers were able to differentiate between C. cayetanensis, nonhuman primate species of Cyclospora, and Eimeria species. As a diagnostic tool, the SNP PCR protocol described here presents a more rapid and sensitive alternative to the currently available PCR-RFLP detection method. In addition, the specificity of these diagnostic primers removes the uncertainty that can be associated with analyses of foods or environmental sources suspected of harboring potential human parasitic pathogens.  相似文献   
67.
It has previously been shown that platelet-free human monocytes, when properly incubated in the presence of animal and human sera, became capable of producing large amounts of thromboxane A2 and prostaglandin E2. The characteristics of these processes are reported here. Prostaglandin biosynthesis was time and cell concentration dependent; 24 h of incubation at 37 degrees C and 0.5 X 10(6) cells per ml medium were found to give the most reproducible results. Human monocytes produced thromboxane A2 and prostaglandin E2 in a typical ratio which ranged from 2.0 to 5.0 (28 experiments). Animal and human sera were similarly effective, while serum obtained from platelet-free blood was much less active. The activity of all sera tested was stable to heating (100 degrees C for 2-10 min) and extreme pH values (pH 2 and 11). It was unstable when the serum was heated at pH 11 and after 2-mercaptoethanol treatment. These observations prompted us to check the effect of polypeptide growth factors having properties similar to those reported above, such as platelet-derived growth factor, fibroblast growth factor, epidermal growth factor as well as insulin and transferrin. None of these, alone or in various combinations, was capable of eliciting a stimulation comparable with that of serum. Stimulation due to sera was, as expected, dose dependently inhibited by acetylsalicylic acid and more efficiently by indomethacin; unexpectedly it was also inhibited by protein synthesis inhibitors such as actinomycin D and cycloheximide in conditions under which no toxic effect of the drugs was evident. On the basis of these results we conclude that: (a) polypeptide growth factor(s) with a molecular weight at least 30 000 (as judged by Amicon ultrafiltration) is involved in the regulation of prostaglandin biosynthesis); (b) such a factor(s) acts by inducing rather than by activating the cyclooxygenase system.  相似文献   
68.
Molecular Biology Reports - In recent years, new treatments with novel action mechanisms have been explored for advanced non-small cell lung cancer (NSCLC). Retinoids promote cancer cell...  相似文献   
69.
GTP binding regulatory protein (G protein)‐coupled receptors can activate MAPK pathways via G protein‐dependent and ‐independent mechanisms. However, the physiological outcomes correlated with the cellular signaling events are not as well characterized. In this study, we examine the involvement of G protein and β‐arrestin 2 pathways in kappa opioid receptor‐induced, extracellular signal‐regulated kinase 1/2 (ERK1/2)‐mediated proliferation of both immortalized and primary astrocyte cultures. As different agonists induce different cellular signaling pathways, we tested the prototypic kappa agonist, U69593 as well as the structurally distinct, non‐nitrogenous agonist, C(2)‐methoxymethyl salvinorin B (MOM‐Sal‐B). In immortalized astrocytes, U69593, activated ERK1/2 by a rapid (min) initial stimulation that was sustained over 2 h and increased proliferation. Sequestration of activated Gβγ subunits attenuated U69593 stimulation of ERK1/2 and suppressed proliferation in these cells. Furthermore, small interfering RNA silencing of β‐arrestin 2 diminished sustained ERK activation induced by U69593. In contrast, MOM‐Sal‐B induced only the early phase of ERK1/2 phosphorylation and did not affect proliferation of immortalized astrocytes. In primary astrocytes, U69593 produced the same effects as seen in immortalized astrocytes. MOM‐Sal‐B elicited sustained ERK1/2 activation which was correlated with increased primary astrocyte proliferation. Proliferative actions of both agonists were abolished by either inhibition of ERK1/2, Gβγ subunits or β‐arrestin 2, suggesting that both G protein‐dependent and ‐independent ERK pathways are required for this outcome.  相似文献   
70.
Reliable prediction of free energy changes upon amino acid substitutions (ΔΔGs) is crucial to investigate their impact on protein stability and protein–protein interaction. Advances in experimental mutational scans allow high-throughput studies thanks to multiplex techniques. On the other hand, genomics initiatives provide a large amount of data on disease-related variants that can benefit from analyses with structure-based methods. Therefore, the computational field should keep the same pace and provide new tools for fast and accurate high-throughput ΔΔG calculations. In this context, the Rosetta modeling suite implements effective approaches to predict folding/unfolding ΔΔGs in a protein monomer upon amino acid substitutions and calculate the changes in binding free energy in protein complexes. However, their application can be challenging to users without extensive experience with Rosetta. Furthermore, Rosetta protocols for ΔΔG prediction are designed considering one variant at a time, making the setup of high-throughput screenings cumbersome. For these reasons, we devised RosettaDDGPrediction, a customizable Python wrapper designed to run free energy calculations on a set of amino acid substitutions using Rosetta protocols with little intervention from the user. Moreover, RosettaDDGPrediction assists with checking completed runs and aggregates raw data for multiple variants, as well as generates publication-ready graphics. We showed the potential of the tool in four case studies, including variants of uncertain significance in childhood cancer, proteins with known experimental unfolding ΔΔGs values, interactions between target proteins and disordered motifs, and phosphomimetics. RosettaDDGPrediction is available, free of charge and under GNU General Public License v3.0, at https://github.com/ELELAB/RosettaDDGPrediction .  相似文献   
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