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81.
Rottoli P Magi B Perari MG Liberatori S Nikiforakis N Bargagli E Cianti R Bini L Pallini V 《Proteomics》2005,5(5):1423-1430
The aim of this study was to analyze the type of immune response (Th1, Th2) and protein composition of bronchoalveolar lavage (BAL) of patients with sarcoidosis, pulmonary fibrosis associated with systemic sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF). Flow cytometry analysis of intracellular cytokines revealed different patterns: in IPF and SSc Th2 profiles were predominant, whereas in sarcoidosis Th1 prevailed. The proteomic analysis of BAL fluid (BALF) showed that there were quantitative differences between the three diseases. These were more evident between sarcoidosis and IPF, confirming our previous observations, whereas SSc had an intermediate profile between the two, however with some peculiarities. Comparison of BALF protein maps, constructed with the same quantity of total proteins, enabled us to identify the main profiles of the three diseases: an increase in plasma protein prevalent in sarcoidosis and also present in SSc, though for fewer proteins with respect to IPF and a greater abundance of low molecular weight proteins, mainly locally produced, in IPF. These findings are in line with the different pathogenesis of these diseases: IPF is considered a prevalently fibrotic disorder limited to the lung, with intense local production of functionally different proteins, whereas sarcoidosis and SSc are systemic immunoinflammatory diseases. 相似文献
82.
Stefano Pluchino Lucia Zanotti Elena Brambilla Patrizia Rovere-Querini Annalisa Capobianco Clara Alfaro-Cervello Giuliana Salani Chiara Cossetti Giovanna Borsellino Luca Battistini Maurilio Ponzoni Claudio Doglioni Jose Manuel Garcia-Verdugo Giancarlo Comi Angelo A. Manfredi Gianvito Martino 《PloS one》2009,4(6)
Background
The systemic injection of neural stem/precursor cells (NPCs) provides remarkable amelioration of the clinico-pathological features of experimental autoimmune encephalomyelitis (EAE). This is dependent on the capacity of transplanted NPCs to engage concurrent mechanisms of action within specific microenvironments in vivo. Among a wide range of therapeutic actions alternative to cell replacement, neuroprotective and immune modulatory capacities of transplanted NPCs have been described. However, lacking is a detailed understanding of the mechanisms by which NPCs exert their therapeutic plasticity. This study was designed to identify the first candidate that exemplifies and sustains the immune modulatory capacity of transplanted NPCs.Methodology/Principal Findings
To achieve the exclusive targeting of the peripheral immune system, SJL mice with PLP-induced EAE were injected subcutaneously with NPCs and the treatment commenced prior to disease onset. NPC-injected EAE mice showed significant clinical improvement, as compared to controls. Exogenous NPCs lacking the expression of major neural antigens were reliably (and for long-term) found at the level of draining lymph nodes, while establishing sophisticated anatomical interactions with lymph node cells. Importantly, injected NPCs were never found in organs other than lymph nodes, including the brain and the spinal cord. Draining lymph nodes from transplanted mice showed focal up-regulation of major developmental stem cell regulators, such as BMP-4, Noggin and Sonic hedgehog. In lymph nodes, injected NPCs hampered the activation of myeloid dendritic cells (DCs) and steadily restrained the expansion of antigen-specific encephalitogenic T cells. Both ex vivo and in vitro experiments identified a novel highly NPC-specific–BMP-4-dependent–mechanism hindering the DC maturation.Conclusion/Significance
The study described herein, identifies the first member of the TGF β/BMP family of stem cell regulators as a novel tolerogenic factor released by NPCs. Full exploitation of this pathway as an efficient tool for vaccination therapy in autoimmune inflammatory conditions is underway. 相似文献83.
Stereospecific synthesis of "para-hydroxymexiletine" and sodium channel blocking activity evaluation
Catalano A Carocci A Fracchiolla G Franchini C Lentini G Tortorella V De Luca A De Bellis M Desaphy JF Conte Camerino D 《Chirality》2004,16(2):72-78
Both enantiomers of "para-hydroxymexiletine" (PHM), one of the main metabolites of mexiletine, were synthesized and fully characterized. Properties of (R)- and (S)-PHM, in terms of blocking potency and stereoselectivity on frog skeletal muscle Na(+) channels, were evaluated. The presence of a hydroxy group on the aryloxy moiety in the 4-position, as in PHM, reduced potency with respect to mexiletine in reducing I(Na max). However, PHM showed clear use-dependent behavior similar to that of mexiletine and, in contrast with what is observed with the parent compound, maintained its stereoselectivity during the use-dependent block. Chirality 16:72-78, 2004. 相似文献
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86.
Notomista E Pennacchio F Cafaro V Smaldone G Izzo V Troncone L Varcamonti M Di Donato A 《Microbial ecology》2011,61(3):582-594
Novosphingobium sp. PP1Y, isolated from a surface seawater sample collected from a closed bay in the harbour of Pozzuoli (Naples, Italy),
uses fuels as its sole carbon and energy source. Like some other Sphingomonads, this strain can grow as either planktonic
free cells or sessile-aggregated flocks. In addition, this strain was found to grow as biofilm on several types of solid and
liquid hydrophobic surfaces including polystyrene, polypropylene and diesel oil. Strain PP1Y is not able to grow on pure alkanes
or alkane mixtures but is able to grow on a surprisingly wide range of aromatic compounds including mono, bi, tri and tetracyclic
aromatic hydrocarbons and heterocyclic compounds. During growth on diesel oil, the organic layer is emulsified resulting in
the formation of small biofilm-coated drops, whereas during growth on aromatic hydrocarbons dissolved in paraffin the oil
layer is emulsified but the drops are coated only if the mixtures contain selected aromatic compounds, like pyrene, propylbenzene,
tetrahydronaphthalene and heterocyclic compounds. These peculiar characteristics suggest strain PP1Y has adapted to efficiently
grow at the water/fuel interface using the aromatic fraction of fuels as the sole carbon and energy source. 相似文献
87.
Yang S Gattinoni L Luca G Liu F Ji Y Yu Z Restifo NP Rosenberg SA Morgan RA 《Cancer immunology, immunotherapy : CII》2011,60(5):739-749
The T-lymphocyte pool can be subdivided into naïve (Tn), effector memory (Tem), and central memory (Tcm) T cells. In this study, we characterized in vitro short-term cultured anti-tumor human T lymphocytes generated by lentiviral transduction with an anti-tumor antigen TCR vector. Within 2 weeks of in vitro culture, the cultured T cells showed a Tcm-like phenotype illustrated by a high percentage of CD62L and CD45RO cells. When the cells were sorted into populations that were CD45RO+/CD62L-(Tem), CD45RO+/CD62L+(Tcm), or CD45ROlow/CD62L+(Tn) and co-cultured with antigen-matched tumor lines, the magnitude of cytokine release from these populations for IFNγ (Tn < Tcm < Tem) and IL-2 (Tn > Tcm > Tem) mimicked the types of immune cell responses observed in vivo. In comparing cell-mediated effector function, Tn were found to be deficient (relative to Tcm and Tem) in the ability to form conjugates with tumor cells and subsequent lytic activity. Moreover, analysis of the gene expression profiles of the in vitro cultured and sorted T-cell populations also demonstrated patterns consistent with their in vivo counterparts. When Tcm and Tem were tested for the ability to survive in vivo, Tcm displayed significantly increased engraftment and persistence in NOD/SCID/γc?/? mice. In general, a large percentage of in vitro generated anti-tumor T lymphocytes mimic a Tcm-like phenotype (based on phenotype, effector function, and increased persistence in vivo), which suggests that these Tcm-like cultured T cells may be optimal for adoptive immunotherapy. 相似文献
88.
Luca Di Angelo Paolo Di Stefano Andrea Spezzaneve 《Computer methods in biomechanics and biomedical engineering》2013,16(11):1213-1220
The methods for symmetry line detection presented in the literature are typically suited to analyse symmetric upright postures, both standing and seated. The proposed method focuses on the symmetry line detection in subjects assuming asymmetric postures in which this line falls far outside the sagittal plane. The proposed approach evaluates the symmetry line by means of an autoregressive process in order to determine the set of planes suited to slice the back coherently with its geometric spatial configuration. The method is analysed assuming the cutaneous marking as reference and it is compared with a previous one, also developed by these authors. Results are analysed and critically discussed. 相似文献
89.
90.
Neri LM Borgatti P Tazzari PL Bortul R Cappellini A Tabellini G Bellacosa A Capitani S Martelli AM 《Molecular cancer research : MCR》2003,1(3):234-246
Disruption of the apoptotic pathways may account for resistance to chemotherapy and treatment failures in human neoplastic disease. To further evaluate this issue, we isolated a HL-60 cell clone highly resistant to several drugs inducing apoptosis and to the differentiating chemical all-trans-retinoic acid (ATRA). The resistant clone displayed an activated phosphoinositide 3-kinase (PI3K)/AKT1 pathway, with levels of phosphatidylinositol (3,4,5) trisphosphate higher than the parental cells and increased levels of both Thr 308 and Ser 473 phosphorylated AKT1. In vitro AKT1 activity was elevated in resistant cells, whereas treatment of the resistant cell clone with two inhibitors of PI3K, wortmannin or Ly294002, strongly reduced phosphatidylinositol (3,4,5) trisphosphate levels and AKT1 activity. The inhibitors reversed resistance to drugs. Resistant cells overexpressing either dominant negative PI3K or dominant negative AKT1 became sensitive to drugs and ATRA. Conversely, if parental HL-60 cells were forced to overexpress an activated AKT1, they became resistant to apoptotic inducers and ATRA. There was a tight relationship between the activation of the PI3K/AKT1 axis and the expression of c-IAP1 and c-IAP2 proteins. Activation of the PI3K/AKT1 axis in resistant cells was dependent on enhanced tyrosine phosphorylation of the p85 regulatory subunit of PI3K, conceivably due to an autocrine insulin-like growth factor-I production. Our findings suggest that an up-regulation of the PI3K/AKT1 pathway might be one of the survival mechanisms responsible for the onset of resistance to chemotherapeutic and differentiating therapy in patients with acute leukemia. 相似文献