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71.
The influence of Met-enkephalin on mitogenic stimulation of mouse splenocytes was investigated. Met-enkephalin (ME) was shown to suppress proliferation induced by Concanavalin A and activate proliferation induced by Staphylococcus enterotoxin A. Both effects were revealed at low (down to 10(-14) M) concentration of pentapeptide. Naloxone reversed ME influence on cell activation. The number of receptors for naloxone was shown to increase up to 2.5-fold during mitogenic activation. The difference in expression of various types of opioid receptors at mitogenic stimulation was demonstrated by ligand displacement experiments.  相似文献   
72.
Echo-planar imaging (EPI) is an ultrafast magnetic resonance (MR) imaging technique prone to geometric distortions. Various correction techniques have been developed to remedy these distortions. Here improvements of the point spread function (PSF) mapping approach are presented, which enable reliable and fully automated distortion correction of echo-planar images at high field strengths. The novel method is fully compatible with EPI acquisitions using parallel imaging. The applicability of parallel imaging to further accelerate PSF acquisition is shown. The possibility of collecting PSF data sets with total acceleration factors higher than the number of coil elements is demonstrated. Additionally, a new approach to visualize and interpret distortions in the context of various imaging and reconstruction methods based on the PSF is proposed. The reliable performance of the PSF mapping technique is demonstrated on phantom and volunteer scans at field strengths of up to 4 T.  相似文献   
73.
We have previously described designing of polyepitope immunogens TBI and TCI, to stimulate the humoral and cellular immune responses to HIV-1. Here, immunogens TBI and TCI were used to create new vaccine construct named CombiHIVvac (Combined HIV-1 vaccine). CombiHIVvac is a virus-like particles (VLP) containing the DNA vaccine pcDNA-TCI as a core encapsulated within a spermidine-polyglucin-TBI conjugate. The immunogenic and toxic properties of the candidate vaccine CombiHIVvac have been studied. CombiHIVvac induces a strong humoral and CTL responses in mice; the antibodies are highly specific and are able to neutralize HIV-1 in vitro. Preclinical study demonstrated that CombiHIVvac does not cause long-term changes in physiological, biochemical and morphological parameters in immunized animals and thus can be recommended for clinical trials.  相似文献   
74.
In this work, the opportunities and challenges for the use of parallel transmission in combination with 2D RF pulses designed on EPI‐based excitation trajectories for diffusion‐weighted imaging (DWI) with reduced FOV are presented and analyzed in detail. The use of localized excitation allows for shortening of the EPI read‐out, which is especially important for EPI applications outside of the brain. DWI is chosen as a practically important and relevant example demonstrating the key aspects of 2D spatial selection. The properties of accelerated pulses are explored experimentally in phantoms for two different schemes, in which the thickness of the excited limited slices is encoded either along the frequency or phase encoding directions of the excitation trajectory. The feasibility of application of parallel transmission for MR imaging in humans is analyzed based on several pilot experiments. Although the parallel transmission acceleration is demonstrated to work in some examples in the spinal cord and abdomen, the results also uncover a number of challenges. Nonetheless, the reduction of FOV in the phase encoding direction of the read‐out train along with the associated substantial shortening of the minimum echo train length and reduction of geometric distortions motivates further search for an advantageous use of the parallel transmit technology in EPI applications. © 2015 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 45B: 153–173, 2015  相似文献   
75.
我非常高兴向大家推荐这份发展中国家幽门螺杆菌(H.priori)临床指南。该指南的编译是由数位在该领域具有丰富临床经验的世界知名专家共同完成的。  相似文献   
76.
Abstrakt Vergibt ein behandelnder Arzt eine Laboruntersuchung an einen externen Laborarzt, kommt entweder direkt ein Vertragsverh?ltnis zwischen dem Laborarzt und dem Patienten zustande oder der Patient haftet dem Laborarzt aus den Grunds?tzen der Gesch?ftsführung ohne Auftrag.  相似文献   
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