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241.
Analysis of mitochondrial DNA restriction fragment length polymorphism in
European anchovy (Engraulis encrasicolus) revealed a large number of
mitotypes that form two distinct clusters (phylads). Phylad A consists of
one common mitotype and many rare secondary mitotypes that are one
mutational step removed from the main type. Nucleotide diversity and number
of homoplasious changes are low. Phylad B has a complex pattern of mitotype
connectedness, high nucleotide diversity, and a large number of
homoplasious changes. It is suggested that the two phylads evolved in
isolation from each other and that present coexistence is the result of a
secondary contact. Moreover, phylad A has a "star" phylogeny, which
suggests that it has evolved in a population that experienced a drastic
bottleneck followed by an explosion of size. Phylad A is practically the
only phylad present in the Black Sea, with its frequency dropping to 85% in
the northern Aegean, and to 40% in the rest of Mediterranean and the Bay of
Biscay. The Black Sea is, therefore, the most likely place of origin of
phylad A. Molecular data are consistent with a population bottleneck in the
Black Sea during the last glaciation event and a subsequent exit of phylad
A with the outflow into the Aegean following the ice melting. Phylogenetic
analysis of anchovy mtDNA provides a reconstruction of population history
in the Mediterranean, which is consistent with the geological information.
相似文献
242.
Antonios N. Gargalionis Lina S. Malakou Christos Adamopoulos Christina Piperi Irene Theohari Marjan Nokhbehsaim James Deschner Georgios Kokkalis Penelope Korkolopoulou Evangelia Papadavid Athanasios G. Papavassiliou Efthimia K. Basdra 《生物化学与生物物理学报:疾病的分子基础》2018,1864(10):3468-3476
Psoriatic plaques tend to localize to the knees and elbows, areas that are particularly subject to mechanical stress resulting from bending and friction. Moreover, plaques often develop at sites of mechanical trauma or injury (Koebner phenomenon). Nevertheless, mechanotransduction has never been linked to psoriasis. Polycystins (polycystin-1, PC1; polycystin-2, PC2) are mechanosensitive molecules that function as key regulators of cellular mechanosensitivity and mechanotransduction. The aim of this in vitro study was to investigate the role of polycystins in the development of psoriasis. We showed that PC1 knockdown in HaCaT cells led to an elevated mRNA expression of psoriasis-related biomarkers Ki-67, IL-6, TNF-α, VEGF and Bcl-2, while PC1 functional inhibition was accompanied by increased cell proliferation and migration of HaCaT cells. In addition, PC1 knockdown via siRNA in HaCaT cells was followed by activation of critical molecules of the mTOR and MAPK pathways and this mTOR pathway activation was ERK-dependent. Furthermore, loss of PC1 protein expression and elevated levels of activated mTOR substrates were also observed in human samples of psoriatic plaques. Overall, our study suggests that the PC1/ERK/mTOR signaling axis represents a novel potential mechanism in psoriasis pathogenesis. 相似文献
243.
244.
Photovoltaic Devices: Plasmonic Backscattering Effect in High‐Efficient Organic Photovoltaic Devices (Adv. Energy Mater. 2/2016)
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245.
Kontou M Pournaras S Kristo I Ikonomidis A Maniatis AN Stathopoulos C 《Biochemistry》2007,46(45):13170-13178
Metallo-beta-lactamases (MBLs) are considered an emerging family of Zn2+-dependent enzymes that significantly contribute to the resistance of many nosocomial pathogens against beta-lactam antimicrobials. Since these plasmid-encoded enzymes constitute specific molecular targets for beta-lactams, their exact mode of action is greatly important in deploying efficient anti-infective treatments and for the control of severe multi-resistant nosocomial infections, which becomes a global problem. A novel hybrid VIM-1/VIM-2-type beta-lactamase (named VIM-12) has recently been identified in a clinical isolate of Klebsiella pneumoniae in Greece. The sequence of this enzyme is highly similar with that of VIM-1 at its N-terminal region and with that of VIM-2 at its C-terminal region, raising the question of whether this sequence similarity reflects also a similar functional role. Moreover, the possible contribution of this novel beta-lactamase to the overall antibiotic resistance of this specific clinical isolate was investigated. The gene encoding VIM-12 was cloned and expressed, and the recombinant enzyme was used for detailed kinetic analysis, using a variety of beta-lactam antibiotics. VIM-12 was found to exhibit narrow substrate specificity, compared to other known beta-lactamases, limited mainly to penicillin and to a much lesser extent to imipenen. Interestingly, meropenem was found to act as a noncompetitive inhibitor of the enzyme, although the active site of VIM-12 exhibited complete conservation of residues among VIM enzymes. We conclude that VIM-12 represents a novel and unique member of the family of known metallo-beta-lactamases, exhibiting atypical substrate specificity. 相似文献
246.
247.
Pedro Pedrosa Amelie Heuer-Jungemann Antonios G. Kanaras Alexandra R. Fernandes Pedro V. Baptista 《Journal of nanobiotechnology》2017,15(1):85
Background
Anti-angiogenic therapy has great potential for cancer therapy with several FDA approved formulations but there are considerable side effects upon the normal blood vessels that decrease the potential application of such therapeutics. Chicken chorioallantoic membrane (CAM) has been used as a model to study angiogenesis in vivo. Using a CAM model, it had been previously shown that spherical gold nanoparticles functionalised with an anti-angiogenic peptide can humper neo-angiogenesis.Results
Our results show that gold nanoparticles conjugated with an anti-angiogenic peptide can be combined with visible laser irradiation to enhance angiogenesis arrest in vivo. We show that a green laser coupled to gold nanoparticles can achieve high localized temperatures able to precisely cauterize blood vessels. This combined therapy acts via VEGFR pathway inhibition, leading to a fourfold reduction in FLT-1 expression.Conclusions
The proposed phototherapy extends the use of visible lasers in clinics, combining it with chemotherapy to potentiate cancer treatment. This approach allows the reduction of dose of anti-angiogenic peptide, thus reducing possible side effects, while destroying blood vessels supply critical for tumour progression.248.
Antonios Kolimenakis Sabine Heinz Michael Lowery Wilson Volker Winkler Laith Yakob Antonios Michaelakis Dimitrios Papachristos Clive Richardson Olaf Horstick 《PLoS neglected tropical diseases》2021,15(9)
BackgroundThis systematic review aims to assess how different urbanisation patterns related to rapid urban growth, unplanned expansion, and human population density affect the establishment and distribution of Aedes aegypti and Aedes albopictus and create favourable conditions for the spread of dengue, chikungunya, and Zika viruses.Methods and findingsFollowing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review was conducted using the PubMed, Virtual Health Library, Cochrane, WHO Library Database (WHOLIS), Google Scholar, and and the Institutional Repository for Information Sharing (IRIS) databases. From a total of 523 identified studies, 86 were selected for further analysis, and 29 were finally analysed after applying all inclusion and exclusion criteria. The main explanatory variables used to associate urbanisation with epidemiological/entomological outcomes were the following: human population density, urban growth, artificial geographical space, urban construction, and urban density. Associated with the lack of a global definition of urbanisation, several studies provided their own definitions, which represents one of the study’s limitations. Results were based on 8 ecological studies/models, 8 entomological surveillance studies, 7 epidemiological surveillance studies, and 6 studies consisting of spatial and predictive models. According to their focus, studies were categorised into 2 main subgroups, namely “Aedes ecology” and “transmission dynamics.” There was a consistent association between urbanisation and the distribution and density of Aedes mosquitoes in 14 of the studies and a strong relationship between vector abundance and disease transmission in 18 studies. Human population density of more than 1,000 inhabitants per square kilometer was associated with increased levels of arboviral diseases in 15 of the studies.ConclusionsThe use of different methods in the included studies highlights the interplay of multiple factors linking urbanisation with ecological, entomological, and epidemiological parameters and the need to consider a variety of these factors for designing effective public health approaches. 相似文献
249.
Roser Zaurin Roberto Ferrari Ana Silvina Nacht Jose Carbonell Francois Le
Dily Jofre Font-Mateu Lara
Isabel de
Llobet
Cucalon Enrique Vidal Antonios Lioutas Miguel Beato Guillermo P Vicent 《Nucleic acids research》2021,49(22):12716
Here, we report that in T47D breast cancer cells 50 pM progestin is sufficient to activate cell cycle entry and the progesterone gene expression program. At this concentration, equivalent to the progesterone blood levels found around the menopause, progesterone receptor (PR) binds only to 2800 genomic sites, which are accessible to ATAC cleavage prior to hormone exposure. These highly accessible sites (HAs) are surrounded by well-organized nucleosomes and exhibit breast enhancer features, including estrogen receptor alpha (ERα), higher FOXA1 and BRD4 (bromodomain containing 4) occupancy. Although HAs are enriched in RAD21 and CTCF, PR binding is the driving force for the most robust interactions with hormone-regulated genes. HAs show higher frequency of 3D contacts among themselves than with other PR binding sites, indicating colocalization in similar compartments. Gene regulation via HAs is independent of classical coregulators and ATP-activated remodelers, relying mainly on MAP kinase activation that enables PR nuclear engagement. HAs are also preferentially occupied by PR and ERα in breast cancer xenografts derived from MCF-7 cells as well as from patients, indicating their potential usefulness as targets for therapeutic intervention. 相似文献
250.
Stavropoulos-Kalinoglou A Metsios GS Panoulas VF Douglas KM Nevill AM Jamurtas AZ Kita M Koutedakis Y Kitas GD 《Arthritis research & therapy》2008,10(3):R59