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41.
42.
Rhinoviruses (RV) are the major cause of acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD). Rhinoviruses have been shown to activate macrophages, but rhinovirus replication in macrophages has not been reported. Tumor necrosis factor alpha (TNF-alpha) is implicated in the pathogenesis of acute exacerbations, but its cellular source and mechanisms of induction by virus infection are unclear. We hypothesized that rhinovirus replication in human macrophages causes activation and nuclear translocation of NF-kappaB, leading to TNF-alpha production. Using macrophages derived from the human monocytic cell line THP-1 and from primary human monocytes, we demonstrated that rhinovirus replication was productive in THP-1 macrophages, leading to release of infectious virus into supernatants, but was limited in monocyte-derived macrophages, likely due to type I interferon production, which was robust in monocyte-derived but deficient in THP-1-derived macrophages. Similar to bronchial epithelial cells, only small numbers of cells supported complete virus replication. We demonstrated RV-induced activation of NF-kappaB and colocalization of p65/NF-kappaB nuclear translocation with virus replication in both macrophage types. The infection induced TNF-alpha release in a time- and dose-dependent, RV serotype- and receptor-independent manner and was largely (THP-1 derived) or completely (monocyte derived) dependent upon virus replication. Finally, we established the requirement for NF-kappaB but not p38 mitogen-activated protein kinase in induction of TNF-alpha. These data suggest RV infection of macrophages may be an important source of proinflammatory cytokines implicated in the pathogenesis of exacerbations of asthma and COPD. They also confirm inhibition of NF-kappaB as a promising target for development of new therapeutic intervention strategies.  相似文献   
43.
Two new charge transfer salts of TTF with the counter anions [M(phen)(CN)4] (phen = 1,10-phenanthroline, M = Cr (I) and Fe (II)) are described. The structures consist of alternating stacks of dimerised TTF+ cations and [M(phen)(CN)4] anions and they are linked together by many short S?S contacts and hydrogen bonds. Within the organic stack, two dimerised TTF+ cations are arranged in a slipped face-to-face mode with short intra-dimer and long inter-dimer S?S distances. Strong antiferromagnetic exchange was found in the TTF+ dimers. Conductivity measurements show that compound I is a semiconductor.  相似文献   
44.
Starting from the heterotopic multidentate ligand 1,2-phenylenebis(thio)diacetic acid (1), cis-rac-[PdCl2{1,2-(HOOCCH2S)2C6H42S,S′}] (2), cis-rac-[Rh{1,2-(HOOCCH2S)2C6H42S,S′}(cod)]BF4 (3) and cis-rac-[Ni{1,2-(OOCCH2S)2C6H44O,OS,S′}{cis-(C3H4N2)}2] (4) were prepared and characterised by X-ray diffraction and conventional spectroscopic techniques. Compounds 1-4 show extensive hydrogen-bonded networks (XH?O, X = O, N) in the solid state.  相似文献   
45.
To demonstrate the usefulness of enzyme-linked immunosorbent assay for serodiagnosis of mycobacterioses due to environmental mycobacteria we utilized a panel of glycolipid antigens selective for Mycobacterium avium-intracellulare, Mycobacterium kansasii, Mycobacterium xenopi, Mycobacterium scrofulaceum and Mycobacterium gordonae. The levels of circulating antibodies were determined against the environmental mycobacteria, and Mycobacterium tuberculosis in human immunodeficiency virus-negative and -positive patient sera. The method used immunomagnetic separation of the antigens, with covalent immobilization of antibodies to superparamagnetic amine and carboxyl terminated particles in solutions of the specific antigens. Enzyme-linked immunosorbent assay was performed on 195 patient sera: 34 with infections due to environmental mycobacteria, 114 with tuberculosis, 47 with other respiratory diseases. There were 46 human immunodeficiency virus-1 infected individuals. Among the 34 infections due to environmental mycobacteria, 9 patients were singularly infected with an environmental mycobacterium, and 25 co-infected with both M. tuberculosis and an environmental mycobacterium. Sensitivity, specificity and false positivity ranges were determined for each of the volunteer groups: tuberculosis positive, human immunodeficiency virus negative; tuberculosis positive, human immunodeficiency virus positive; those with infections due to individual environmental mycobacteria (such as M. scrofulaceum and M. kansasii); and those with other respiratory diseases. We demonstrate that such multiple assays, can be useful for the early diagnosis of diverse environmental mycobacterial infections to allow the start of treatment earlier than henceforth.  相似文献   
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The distribution of ion channels in neurons regulates neuronal activity and proper formation of neuronal networks during neuronal development. One of the channels is the hyperpolarization‐activated cyclic nucleotide‐gated (HCN) channel constituting the molecular substrate of hyperpolarization‐activated current (Ih). Our previous study implied a role for the fastest activating subunit HCN1 in the generation of Ih in rat neonatal cortical plate neurons. To better understand the impact of HCN1 in early neocortical development, we here performed biochemical analysis and whole‐cell recordings in neonatal cortical plate and juvenile layer 5 somatosensory neurons of HCN1?/? and control HCN1+/+ mice. Western Blot analysis revealed that HCN1 protein expression in neonatal cortical plate tissue of HCN+/+ mice amounted to only 3% of the HCN1 in young adult cortex and suggested that in HCN1?/? mice other isoforms (particularly HCN4) might be compensatory up‐regulated. At the first day after birth, functional ablation of the HCN1 subunit did not affect the proportion of Ih expressing pyramidal cortical plate neurons. Although the contribution of individual subunit proteins remains open, the lack of HCN1 markedly slowed the current activation and deactivation in individual Ih expressing neurons. However, it did not impair maximal amplitude/density, voltage dependence of activation, and cAMP sensitivity. In conclusion, our data imply that, although expression is relatively low, HCN1 contributes substantially to Ih properties in individual cortical plate neurons. These properties are significantly changed in HCN1?/?, either due to the lack of HCN1 itself or due to compensatory mechanisms. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73: 785–797, 2013  相似文献   
48.
Cellular reprogramming and induced pluripotent stem cell(IPSC) technology demonstrated the plasticity of adult cell fate, opening a new era of cellular modelling and introducing a versatile therapeutic tool for regenerative medicine.While IPSCs are already involved in clinical trials for various regenerative purposes, critical questions concerning their medium-and long-term genetic and epigenetic stability still need to be answered. Pluripotent stem cells have been described in the last decades in various mammalian and human tissues(such as bone marrow, blood and adipose tissue). We briefly describe the characteristics of human-derived adult stem cells displaying in vitro and/or in vivo pluripotency while highlighting that the common denominators of their isolation or occurrence within tissue are represented by extreme cellular stress. Spontaneous cellular reprogramming as a survival mechanism favoured by senescence and cellular scarcity could represent an adaptative mechanism. Reprogrammed cells could initiate tissue regeneration or tumour formation dependent on the microenvironment characteristics. Systems biology approaches and lineage tracing within living tissues can be used to clarify the origin of adult pluripotent stem cells and their significance for regeneration and disease.  相似文献   
49.

Background

Secukinumab, an anti–interleukin-17A monoclonal antibody, improved the signs and symptoms of ankylosing spondylitis (AS) in two phase 3 studies (MEASURE 1 and MEASURE 2). Here, we present 52-week results from the MEASURE 3 study assessing the efficacy and safety of secukinumab 300 and 150 mg subcutaneous maintenance dosing, following an intravenous loading regimen.

Methods

A total of 226 patients were randomized to intravenous secukinumab 10 mg/kg (baseline, weeks 2 and 4) followed by subcutaneous secukinumab 300 mg (IV-300 mg) or 150 mg (IV-150 mg) every 4 weeks, or matched placebo. Patients in the placebo group were re-randomized to subcutaneous secukinumab at a dose of 300 or 150 mg at week 16. The primary endpoint was the Assessment of SpondyloArthritis international Society criteria for 20% improvement (ASAS20) response rate at week 16 in the IV-300 mg or IV-150 mg versus placebo. Other endpoints assessed through week 52 included improvements in ASAS40, ASAS 5/6, Bath Ankylosing Spondylitis Disease Activity Index, and ASAS partial remission responses, as well as the change from baseline in high-sensitivity C-reactive protein levels. Statistical analyses followed a predefined hierarchical hypothesis testing strategy to adjust for multiplicity of testing, with non-responder imputation used for binary variables and mixed-model repeated measures for continuous variables.

Results

The primary efficacy endpoint was met; the ASAS20 response rate was significantly greater at week 16 in the IV-300 mg (60.5%; P?<?0.01) and IV-150 mg (58.1%; P?<?0.05) groups versus placebo (36.8%). All secondary endpoints were met at week 16, except ASAS partial remission in the IV-150 mg group. Improvements achieved with secukinumab in all clinical endpoints at week 16 were also sustained at week 52. Infections, including candidiasis, were more common with secukinumab than with placebo during the placebo-controlled period. During the entire treatment period, pooled incidence rates of Candida infections and grade 3–4 neutropenia were 1.8% for both of these adverse events in secukinumab-treated patients.

Conclusions

Secukinumab (300 mg and 150 mg dose groups) provided rapid, significant and sustained improvement through 52 weeks in the signs and symptoms of patients with AS. The safety profile was consistent with previous reports, with no new or unexpected findings.

Trial registration

ClinicalTrials.gov, NCT02008916. Registered on 8 December 2013. EUDRACT 2013-001090-24. Registered on 24 October 2013). The study was not retrospectively registered.
  相似文献   
50.
There are limited data on essential nutrients in the whole blood of young children. As part of a longitudinal study of the impact on young children and the environment from the introduction of an organic Mn compound into unleaded gasoline in Australia, we have measured a suite of elements in whole blood. The children, aged between 6 and 31 months at recruitment, have been monitored at 6-month intervals for up to 5 years. Blood samples were analysed by inductively coupled plasma mass spectrometry for Ca, Mg, Fe, Mn, Cu, Zn and Pb. Mixed model analyses of 665 blood samples using backward elimination showed significant positive relationships between Ca, Mg and Zn and season, variable relationships with time, but no association with gender or traffic exposure. The elements Ca, Mg and Zn showed higher concentrations in summer compared with winter, whereas Fe and Pb showed lower concentrations in summer compared with winter. Concentrations of all elements except Fe showed significant effects over time: Ca, Cu, Mg, Pb and Mn showed decreases over time, whereas Zn showed an increase. The mixed model analyses with the individual elements as the dependent variable showed some interesting relationships and require further follow-up as some of these appear to conflict with pre-existing concepts, although the multi-element data on which these concepts are based are limited. The variance for blood Pb and blood Mn arising from the other elements was small with 0.5% in the case of blood Pb and 3.7% for blood Mn.  相似文献   
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