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101.
The isolation and identification of intermediates formed in the course of the activation of dioxygen at transition metal centers reveals important mechanistic insights concerning such processes. We previously reported the reaction of the dinuclear CrII complex [L2Cr2(MeCN)2][Li(MeCN)]2 (L=PhSi(OSiPh2O)3) ( 5 ) with dioxygen, which resulted in the formation of the CrIV oxo complex [L2Cr2O2][Li(THF)2]2 ( 6 ), as the final room temperature stable product. Here we now report the isolation and characterization of an intermediate en route to 6 , namely the dinuclear CrIII superoxo complex [L2Cr2(O2)2][Li(MeCN)]2 ( 7 ). 7 is the first example of a structurally characterized dinuclear CrIII superoxo complex with two independent side-on bound superoxo ligands. Reactivity studies outline the capability of this superoxo complex to activate weak O−H bonds.  相似文献   
102.
The autonomic nervous system (ANS) and the immune system are deeply interrelated. The ANS regulates both innate and adaptive immunity through the sympathetic and parasympathetic branches, and an imbalance in this system can determine an altered inflammatory response as typically observed in chronic conditions such as systemic autoimmune diseases. Rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis all show a dysfunction of the ANS that is mutually related to the increase in inflammation and cardiovascular risk. Moreover, an interaction between ANS and the gut microbiota has direct effects on inflammation homeostasis. Recently vagal stimulation techniques have emerged as an unprecedented possibility to reduce ANS dysfunction, especially in chronic diseases characterized by pain and a decreased quality of life as well as in chronic inflammation.  相似文献   
103.
Limiting bone resorption and regenerating bone tissue are treatment goals in myeloma bone disease (MMBD). Physical stimuli such as mechanical loading prevent bone destruction and enhance bone mass in the MOPC315.BM.Luc model of MMBD. It is unknown whether treatment with the Bruton’s tyrosine kinase inhibitor CC-292 (spebrutinib), which regulates osteoclast differentiation and function, augments the anabolic effect of mechanical loading. CC-292 was administered alone and in combination with axial compressive tibial loading in the MOPC315.BM.Luc model for three weeks. However, neither CC-292 alone nor its use in combination with mechanical loading was more effective in reducing osteolytic bone disease or rescuing bone mass than mechanical stimuli alone, as evidenced by microcomputed tomography (microCT) and histomorphometric analysis. Further studies are needed to investigate novel anti-myeloma and anti-resorptive strategies in combination with physical stimuli to improve treatment of MMBD.  相似文献   
104.
105.
A viscous, gel-like phase was found in ultracentrifuged human upper intestinal contents collected during rapid fat lipolysis. This “gel” phase was layered in the ultracentrifuge tube between the micellar and oil phase. The gel contained lipids typical of the micellar and not the oil phase. The concentration of these lipids was higher and the ratio of total bile salts to lipids was lower in the gel than in the micellar phase. The gel, unlike the micellar phase, was birefringent between crossed polarizers. These data demonstrate that lipids in this gel phase can form liquid crystals in the gut during fat digestion.  相似文献   
106.
The Gal beta(1-3)GalNAc-binding lectin jacalin is known to specifically induce the proliferation of human CD4+ T lymphocytes in the presence of autologous monocytes and to interact with the CD4 molecule and block HIV-1 infection of CD4+ cells. We further show that jacalin-induced proliferation is characterized by an unusual pattern of T cell activation and cytokine production by human peripheral blood mononuclear cells (PBMC). A cognate interaction between T cells and monocytes was critical for jacalin-induced proliferation, and human recombinant interleukin (IL)-1 and IL-6 did not replace the co-stimulatory activity of monocytes. Blocking studies using monoclonal antibodies (mAb) point out the possible importance of two molecular pathways of interaction, the CD2/LFA-3 and LFA-1/ICAM-1 pathways. One out of two anti-CD4 mAb abolished jacalin responsiveness. Jacalin induced interferon-gamma and high IL-6 secretion, mostly by monocytes, and no detectable IL-2 synthesis or secretion by PBMC. In contrast, jacalin-stimulated Jurkat T cells secreted IL-2. CD3- Jurkat cell variants failed to secrete IL-2, suggesting the involvement of the T cell receptor/CD3 complex pathway in jacalin signaling. IL-2 secretion by CD4- Jurkat variant cells was delayed and lowered. In addition to CD4, jacalin interacts with the CD5 molecule. Jacalin-CD4 interaction and the proliferation of PBMC, as well as IL-2 secretion by Jurkat cells were inhibited by specific jacalin-competitive sugars.  相似文献   
107.
108.
The continuous cell-to-cell mapping technique (CCCMT) is a recently proposed Markovian approach which can be used for the dynamic reliability and safety analysis of process control systems, as well as for the global analysis of nonlinear dynamic systems in general. A parametric study is performed on the computational efficiency of CCCMT as a function of various integration schemes. The results show that a variable stepsize scheme is desirable with a sufficient required precision. Among the integration schemes considered, a fourth order Runge-Kutta scheme seems to be preferable for short term simulations and the mid-point implicit scheme seems to be preferable for long term simulations or to obtain the steady-state system behavior.  相似文献   
109.
Schizophrenic and control participants received 2 blocks of trials in each experiment. In 1 block they were exposed to regular priming trials (doctor–nurse), and in another block a nonlexical probe was presented at prime onset for 40 ms. Regardless of stimulus onset asynchrony (SOA), the schizophrenic patients showed hyperpriming when no distractor was present. Paying attention to the distracting stimulus reduced priming in the patient group irrespective of SOA. Under certain situations, the reduction in priming appeared even when participants were asked to ignore the distracting stimulus. Thus, even a nonsemantic distractor may be detrimental to schizophrenic patients' language processing. That SOA did not modulate the reduction in priming effect is consistent with the suggestion that attentional resources are required even with short prime–target intervals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
BACKGROUND: The development of venous access devices (VADs) and portable infusion pumps has enabled chemotherapy to be administered continuously within the home environment. AIM: The objective of this study was to describe the experience of establishing an ambulatory chemotherapy programme for patients receiving protracted infusions (PVIs) of 5-fluorouracil (5-FU). METHODS: The files of all patients receiving PVI 5-FU as a component of their treatment for gastrointestinal malignancy were reviewed. The types of VADs, infusion pump systems and their management were documented. Information packages and education programmes were developed for patients. RESULTS: Seventy-four patients with gastrointestinal cancer were studies. At the end of the period the Portacath was the preferred VAD, while both pumps used were found to have advantages and disadvantages. The choice of pump was decided more by patient preference than systematic differences in performance of the pumps. CONCLUSIONS: The findings in this review confirm that, with close attention to the potential pitfalls of ambulatory chemotherapy, an acceptable service can be provided.  相似文献   
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