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71.
Cees GM Kallenberg Arjan Vissink Frans GM Kroese Wayel H Abdulahad Hendrika Bootsma 《Arthritis research & therapy》2011,13(1):205
In vitro and in vivo experimental data have pointed to new immunopathogenic mechanisms in primary Sj?gren's syndrome (pSS). The availability of
targeted treatment modalities has opened new ways to selectively target these mechanistic pathways in vivo. This has taught us that the role of proinflammatory cytokines, in particular TNFα, is not crucial in the immunopathogenesis
of pSS. B cells appear to play a major role, as depletion of B cells leads to restoration of salivary flow and is efficacious
for treatment of extraglandular manifestations and mucosa-associated lymphoid tissue lymphoma. B cells also orchestrate T-cell
infiltration and ductal epithelial dearrangement in the salivary glands. Gene profiling of salivary gland tissue in relation
to B-cell depletion confirms that the axis of IFNα, B-cell activating factor, B-cell activation, proliferation and survival
constitutes a major pathogenic route in pSS. 相似文献
72.
In anti-neutrophil cytoplasmic autoantibody-associated vasculitides (AAV), several observations support a key role of T-helper
cells (CD4+ T cells) in disease pathophysiology. An expanded population of effector memory CD4+ T cells in AAV patients may contribute to tissue injury and disease progression. In addition, functional impairment of regulatory
T cells (TRegs) is reported in AAV patients. A fraction of TRegs have the capacity to differentiate into Th17 cells in the context of a proinflammatory environment. Therefore, nonfunctionality
of TRegs described in AAV patients may be caused by their conversion into IL-17-producing cells that may contribute to granulomatous
vasculitis. Further investigations directed at the plasticity of TRegs in AAV patients are warranted. 相似文献
73.
Improving salt tolerance of economically important plants is imperative to cope with the increasing soil salinity in many
parts of the world. Mutation breeding has been widely used to improve plant performance under salinity stress. In this study,
we have mutagenized Echinochloa crusgalli L. with sodium azide and three selected mutants (designated fows A) with salt tolerant germination. Their vegetative growth was compared to that of the wild type after short-term and long-term
salt stress. The germination of the three fows A mutants in the presence of inhibitory concentrations of NaCl, KCL, and mannitol was better than that of the wild type.
Early growth of the mutants in the presence of 200 mM NaCl was also better than that of the wild type perhaps due to improved
K+ uptake and enhanced accumulation of sugars particularly sucrose at least in two mutants. But the three mutants and the wild
type responded similarly to long-term salt stress. The tolerance mechanisms during short-term and long-term salt stress are
discussed. 相似文献
74.
Proline induces the expression of salt-stress-responsive proteins and may improve the adaptation of Pancratium maritimum L. to salt-stress 总被引:1,自引:0,他引:1
Khedr AH Abbas MA Wahid AA Quick WP Abogadallah GM 《Journal of experimental botany》2003,54(392):2553-2562
Proline is an important component of salt-stress responses of plants. In this study the role of proline as part of salt-stress signalling in the desert plant Pancratium maritimum L. was examined. The data showed that salt-stress brought about a reduction of the growth and protein content, particularly at 300 mM NaCl, that was significantly increased by exogenous proline. In the leaves, salt-stress up-regulated ubiquitin, a small protein targeting damaged proteins for degradation via the proteasome, up to 5-fold as detected by western blotting. This change was also affected by proline even in non-stressed leaves. However, salt-stress resulted in a decrease in the amount of ubiquitin-conjugates, particularly in the roots, and this effect was reversed by exogenous proline. Severe salt-stress resulted in an inhibition of the antioxidative enzymes catalase and peroxidase as revealed by spectrophotometric assays and activity gels, but the activity of these enzymes was also maintained significantly higher in the presence of proline. Salt-stress also up-regulated several dehydrin proteins, analysed by western blotting, even in non-stressed plants. It is concluded that proline improves the salt-tolerance of Pancratium maritimum L. by protecting the protein turnover machinery against stress-damage and up-regulating stress protective proteins. 相似文献
75.
76.
Structural complexes in the squid giant axon membrane sensitive to ionic concentrations and cardiac glycosides 下载免费PDF全文
Giant nerve fibers of squid Sepioteuthis sepioidea were incubated for 10 min in artificial sea water (ASW) under control conditions, in the absence of various ions, and in the presence of cardiac glycosides. The nerve fibers were fixed in OsO4 and embedded in Epon, and structural complexes along the axolemma were studied. 相似文献
77.
Rice has shallow, weak roots, but it is unknown how much increase in yield potential could be achieved if the root/shoot ratio is corrected. Removing all tillers except the main one, in a japonica (Sakha 101) and an indica (IR64) rice cultivar, instantly increased the root/shoot ratio from 0.21 to 1.16 in Sakha 101 and from 0.16 to 1.46 in IR64. Over 30 days after detillering, the root/shoot ratios of the detillered plants decreased to 0.49 in Sakha 101 and 0.46 in IR64 but remained significantly higher than in the controls. The detillered plants showed two‐ or fourfold increase in the main tiller fresh weight, as a consequence of more positive midday leaf relative water content (RWC), and consistently higher rates of stomatal conductance and photosynthesis, but not transpiration, compared with the controls. The enhanced photosynthesis in Sakha 101 after detillering resulted from both improved water status and higher Rubisco contents whereas in IR64, increasing the Rubisco content did not contribute to improving photosynthesis. Detillering did not increase the carbohydrate contents of leaves but prevented starch depletion at the end of grain filling. The leaf protein content during vegetative and reproductive stages, the grain filling rate, the number of filled grains per panicle were greatly improved, bringing about 38.3 and 35.9% increase in the harvested grain dry weight per panicle in Sakha 101 and IR64, respectively. We provide evidence that improving the root performance by increasing the root/shoot ratio would eliminate the current limitations to photosynthesis and growth in rice. 相似文献
78.
Zea mays L. is less tolerant to drought than Sorghum bicolor L. In the present study, we investigated the response of both plants to drought stress applied under field conditions by withholding water for 10 d. The plant growth in terms of shoot fresh and dry masses was more severely reduced in maize than in sorghum, consistently with reduction of leaf relative water content. Gas exchange was also more inhibited by drought in maize than in sorghum. The water use efficiency (WUE) of maize fluctuated during the day and in response to the drought stress. In contrast, sorghum was able to maintain a largely constant WUE during the day in the well-watered plants as well as in the stressed ones. Studying the expression of four aquaporin genes (PIP1;5, PIP1;6, PIP2;3, and TIP1;2) revealed that PIP1;5 in leaves and PIP2;3 in roots were highly responsive to drought in sorghum but not in maize, where they might have supported a greater water transport. The expression pattern of PIP1;6 suggests its possible role in CO2 transport in control but not droughty leaves of both the plants. TIP1;2 seemed to contribute to water transport in leaves of the control but not droughty plants. We conclude that PIP1;5 and PIP2;3 may have a prominent role in drought tolerance and maintenance of WUE in sorghum plants. 相似文献
79.
Gert Kwakkel Carel GM Meskers Erwin E van Wegen Guus J Lankhorst Alexander CH Geurts Annet A van Kuijk Eline Lindeman Anne Visser-Meily Erwin de Vlugt J Hans Arendzen 《BMC neurology》2008,8(1):49
Background
Main claims of the literature are that functional recovery of the paretic upper limb is mainly defined within the first month post stroke and that rehabilitation services should preferably be applied intensively and in a task-oriented way within this particular time window. EXplaining PLastICITy after stroke (acronym EXPLICIT-stroke) aims to explore the underlying mechanisms of post stroke upper limb recovery. Two randomized single blinded trials form the core of the programme, investigating the effects of early modified Constraint-Induced Movement Therapy (modified CIMT) and EMG-triggered Neuro-Muscular Stimulation (EMG-NMS) in patients with respectively a favourable or poor probability for recovery of dexterity. 相似文献80.
Arvind K Awasthi GM Nagaraja GV Naik Sriramana Kanginakudru K Thangavelu Javaregowda Nagaraju 《BMC genetics》2004,5(1):1