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排序方式: 共有672条查询结果,搜索用时 62 毫秒
621.
Lisa G. van den Hengel Alwine A. Hellingman Anne Yael Nossent Annemarie M. van Oeveren-Rietdijk Margreet R. de Vries C. Arnold Spek Anton Jan van Zonneveld Pieter H. Reitsma Jaap F. Hamming Hetty C. de Boer Henri H. Versteeg Paul H. A. Quax 《PloS one》2013,8(4)
Aims
In collateral development (i.e. arteriogenesis), mononuclear cells are important and exist as a heterogeneous population consisting of pro-inflammatory and anti-inflammatory/repair-associated cells. Protease-activated receptor (PAR)1 and PAR2 are G-protein-coupled receptors that are both expressed by mononuclear cells and are involved in pro-inflammatory reactions, while PAR2 also plays a role in repair-associated responses. Here, we investigated the physiological role of PAR1 and PAR2 in arteriogenesis in a murine hind limb ischemia model.Methods and Results
PAR1-deficient (PAR1-/-), PAR2-deficient (PAR2-/-) and wild-type (WT) mice underwent femoral artery ligation. Laser Doppler measurements revealed reduced post-ischemic blood flow recovery in PAR2-/- hind limbs when compared to WT, while PAR1-/- mice were not affected. Upon ischemia, reduced numbers of smooth muscle actin (SMA)-positive collaterals and CD31-positive capillaries were found in PAR2-/- mice when compared to WT mice, whereas these parameters in PAR1-/- mice did not differ from WT mice. The pool of circulating repair-associated (Ly6C-low) monocytes and the number of repair-associated (CD206-positive) macrophages surrounding collaterals in the hind limbs were increased in WT and PAR1-/- mice, but unaffected in PAR2-/- mice. The number of repair-associated macrophages in PAR2-/- hind limbs correlated with CD11b- and CD115-expression on the circulating monocytes in these animals, suggesting that monocyte extravasation and M-CSF-dependent differentiation into repair-associated cells are hampered.Conclusion
PAR2, but not PAR1, is involved in arteriogenesis and promotes the repair-associated response in ischemic tissues. Therefore, PAR2 potentially forms a new pro-arteriogenic target in coronary artery disease (CAD) patients. 相似文献622.
Elfahmi Komar Ruslan Sieb Batterman Rein Bos Oliver Kayser Herman J. Woerdenbag Wim J. Quax 《Biochemical Systematics and Ecology》2007
The lignan profile of the aerial part of Piper cubeba L. (Piperaceae) was determined using GC, GC–MS and HPLC. The number of lignans found in the leaves was 15, followed by berries and the stalks with respectively 13 and five lignans. This is the first investigation of lignans from the leaves and the stalks of P. cubeba. Cubebin, hinokinin, yatein, isoyatein are common lignans in the genus Piper and appeared as major components in all parts of P. cubeba investigated. 相似文献
623.
Allison M Churcher Jose Martin Pujolar Massimo Milan Peter C Hubbard Rute ST Martins Jo?o L Saraiva Mar Huertas Luca Bargelloni Tomaso Patarnello Ilaria AM Marino Lorenzo Zane Adelino VM Canário 《BMC genomics》2014,15(1)
Background
The vertebrate brain plays a critical role in the regulation of sexual maturation and reproduction by integrating environmental information with developmental and endocrine status. The European eel Anguilla anguilla is an important species in which to better understand the neuroendocrine factors that control reproduction because it is an endangered species, has a complex life cycle that includes two extreme long distance migrations with both freshwater and seawater stages and because it occupies a key position within the teleost phylogeny. At present, mature eels have never been caught in the wild and little is known about most aspects of reproduction in A. anguilla. The goal of this study was to identify genes that may be involved in sexual maturation in experimentally matured eels. For this, we used microarrays to compare the gene expression profiles of sexually mature to immature males.Results
Using a false discovery rate of 0.05, a total of 1,497 differentially expressed genes were identified. Of this set, 991 were expressed at higher levels in brains (forebrain and midbrain) of mature males while 506 were expressed at lower levels relative to brains of immature males. The set of up-regulated genes includes genes involved in neuroendocrine processes, cell-cell signaling, neurogenesis and development. Interestingly, while genes involved in immune system function were down-regulated in the brains of mature males, changes in the expression levels of several receptors and channels were observed suggesting that some rewiring is occurring in the brain at sexual maturity.Conclusions
This study shows that the brains of eels undergo major changes at the molecular level at sexual maturity that may include re-organization at the cellular level. Here, we have defined a set of genes that help to understand the molecular mechanisms controlling reproduction in eels. Some of these genes have previously described functions while many others have roles that have yet to be characterized in a reproductive context. Since most of the genes examined here have orthologs in other vertebrates, the results of this study will contribute to the body of knowledge concerning reproduction in vertebrates as well as to an improved understanding of eel biology.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-799) contains supplementary material, which is available to authorized users. 相似文献624.
625.
626.
Ali Rihani Bram De Wilde Fjoralba Zeka Geneviève Laureys Nadine Francotte Gian Paolo Tonini Simona Coco Rogier Versteeg Rosa Noguera Johannes H. Schulte Angelika Eggert Raymond L. Stallings Frank Speleman Jo Vandesompele Tom Van Maerken 《PloS one》2014,9(12)
Background
Neuroblastoma is a pediatric cancer that exhibits a wide clinical spectrum ranging from spontaneous regression in low-risk patients to fatal disease in high-risk patients. The identification of single nucleotide polymorphisms (SNPs) may help explain the heterogeneity of neuroblastoma and assist in identifying patients at higher risk for poor survival. SNPs in the TP53 pathway are of special importance, as several studies have reported associations between TP53 pathway SNPs and cancer. Of note, less than 2% of neuroblastoma tumors have a TP53 mutation at diagnosis.Patients and Methods
We selected 21 of the most frequently studied SNPs in the TP53 pathway and evaluated their association with outcome in 500 neuroblastoma patients using TaqMan allelic discrimination assays.Results and Conclusion
We investigated the impact of 21 SNPs on overall survival, event-free survival, age at diagnosis, MYCN status, and stage of the disease in 500 neuroblastoma patients. A missense SNP in exon 10 of the CASP8 gene SNP D302H was associated with worse overall and event-free survival in patients with MYCN-amplified neuroblastoma tumors. 相似文献627.
Nicolli Bellotti de Souza Isabel M de Andrade Paula F Carneiro Guilherme AM Jardim Isadora MM de Melo Eufranio N da Silva Júnior Antoniana Ursine Krettli 《Memórias do Instituto Oswaldo Cruz》2014,109(5):546-552
Due to the recent advances of atovaquone, a naphthoquinone, through clinical trials
as treatment for malarial infection, 19 quinone derivatives with previously reported
structures were also evaluated for blood schizonticide activity against the malaria
parasite Plasmodium falciparum. These compounds include 2-hydroxy-3-methylamino
naphthoquinones (2-9), lapachol (10), nor-lapachol (11), iso-lapachol (12), phthiocol
(13) and phenazines (12-20). Their cytotoxicities were also evaluated against human
hepatoma and normal monkey kidney cell lines. Compounds 2 and 5 showed the highest
activity against P. falciparum chloroquine-resistant blood-stage parasites (clone
W2), indicated by their low inhibitory concentration for 50% (IC50) of
parasite growth. The therapeutic potential of the active compounds was evaluated
according to the selectivity index, which is a ratio of the cytotoxicity minimum
lethal dose which eliminates 50% of cells and the in vitro IC50.
Naphthoquinones 2 and 5, with activities similar to the reference antimalarial
chloroquine, were also active against malaria in mice and suppressed parasitaemia by
more than 60% in contrast to compound 11 which was inactive. Based on their in vitro
and in vivo activities, compounds 2 and 5 are considered promising molecules for
antimalarial treatment and warrant further study. 相似文献
628.
Wuelton M Monteiro Fernando FA Val André M Siqueira Gabriel P Franca Vanderson S Sampaio Gisely C Melo Anne CG Almeida Marcelo AM Brito Henry M Peixoto Douglas Fuller Quique Bassat Gustavo AS Romero Oliveira Maria Regina F Lacerda Marcus Vinícius G 《Memórias do Instituto Oswaldo Cruz》2014,109(5):553-568
629.
Linda Spiegelberg Sigrid MA Swagemakers Wilfred FJ van IJcken Edwin Oole Eppo B Wolvius Jeroen Essers Joanna AM Braks 《Molecular medicine (Cambridge, Mass.)》2014,20(1):257-269
A side effect of radiation therapy in the head and neck region is injury to surrounding healthy tissues such as irreversible impaired function of the salivary glands. Hyperbaric oxygen therapy (HBOT) is clinically used to treat radiation-induced damage but its mechanism of action is largely unknown. In this study, we investigated the molecular pathways that are affected by HBOT in mouse salivary glands two weeks after radiation therapy by microarray analysis. Interestingly, HBOT led to significant attenuation of the radiation-induced expression of a set of genes and upstream regulators that are involved in processes such as fibrosis and tissue regeneration. Our data suggest that the TGFβ-pathway, which is involved in radiation-induced fibrosis and chronic loss of function after radiation therapy, is affected by HBOT. On the longer term, HBOT reduced the expression of the fibrosis-associated factor α-smooth muscle actin in irradiated salivary glands. This study highlights the potential of HBOT to inhibit the TGFβ-pathway in irradiated salivary glands and to restrain consequential radiation induced tissue injury. 相似文献
630.
Phage Display of an Intracellular Carboxylesterase of Bacillus subtilis: Comparison of Sec and Tat Pathway Export Capabilities
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Melloney J. Drge Ykelien L. Boersma Peter G. Braun Robbert Jan Buining Mattijs K. Julsing Karin G. A. Selles Jan Maarten van Dijl Wim J. Quax 《Applied microbiology》2006,72(7):4589-4595
Using the phage display technology, a protein can be displayed at the surface of bacteriophages as a fusion to one of the phage coat proteins. Here we describe development of this method for fusion of an intracellular carboxylesterase of Bacillus subtilis to the phage minor coat protein g3p. The carboxylesterase gene was cloned in the g3p-based phagemid pCANTAB 5E upstream of the sequence encoding phage g3p and downstream of a signal peptide-encoding sequence. The phage-bound carboxylesterase was correctly folded and fully enzymatically active, as determined from hydrolysis of the naproxen methyl ester with Km values of 0.15 mM and 0.22 mM for the soluble and phage-displayed carboxylesterases, respectively. The signal peptide directs the encoded fusion protein to the cell membrane of Escherichia coli, where phage particles are assembled. In this study, we assessed the effects of several signal peptides, both Sec dependent and Tat dependent, on the translocation of the carboxylesterase in order to optimize the phage display of this enzyme normally restricted to the cytoplasm. Functional display of Bacillus carboxylesterase NA could be achieved when Sec-dependent signal peptides were used. Although a Tat-dependent signal peptide could direct carboxylesterase translocation across the inner membrane of E. coli, proper assembly into phage particles did not seem to occur. 相似文献