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1.
Chronic infections are considered one of the most severe problems in skin wounds, and bacteria are present in over 90% of chronic wounds. Pseudomonas aeruginosa is frequently isolated from chronic wounds and is thought to be a cause of delayed wound healing. Invariant natural killer T (iNKT) cells, unique lymphocytes with a potent regulatory ability in various inflammatory responses, accelerate the wound healing process. In the present study, we investigated the contribution of iNKT cells in the host defense against P. aeruginosa inoculation at the wound sites. We analyzed the re-epithelialization, bacterial load, accumulation of leukocytes, and production of cytokines and antimicrobial peptides. In iNKT cell–deficient (Jα18KO) mice, re-epithelialization was significantly decreased, and the number of live colonies was significantly increased, when compared with those in wild-type (WT) mice on day 7. IL-17A, and IL-22 production was significantly lower in Jα18KO mice than in WT mice on day 5. Furthermore, the administration of α-galactosylceramide (α-GalCer), a specific activator of iNKT cells, led to enhanced host protection, as shown by reduced bacterial load, and to increased production of IL-22, IL-23, and S100A9 compared that of with WT mice. These results suggest that iNKT cells promote P. aeruginosa clearance during skin wound healing.  相似文献   
2.
In this paper, return link systems for wireless mobile camera using 42 GHz-band in multipath fading environments are proposed. The return link systems for wireless mobile camera require wireless transmission with high reliability as same as the conventional wired camera systems. The proposed return link systems achieve transmission with high reliability by taking into consideration frequency and space diversity techniques. The proposed systems can be classified as 3 three types of return link systems according to diversity techniques: FD (frequency diversity) systems, SD (space diversity) systems and FD+SD system (frequency and space diversity). Computer simulations are carried out in order to confirm the effectiveness of the proposed return link systems. It is confirmed that the proposed three types of return link systems have an advantage about BER performances and effectively exploit frequency and space resources.  相似文献   
3.
Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors.  相似文献   
4.
Monolayers of an amphiphilic nitrophenylazide (ANPA) derivative were prepared and their ability to immobilize a protein molecule by a photochemical binding reaction was demonstrated as a novel means to constitute a biofunctional membrane. Molecular orientations and photoreactions in the ANPA monolayers were investigated by Fourier transform IR spectroscopy. Rapid photolysis of ANPA was observed which reflects decomposition of the azide group to a reactive nitrene radical intermediate. As an enzyme, glucose oxidase (GOD) was immobilized on a monomolecular film of ANPA, coated on a substrate, by means of enzyme adsorption at the solid-solution interface and subsequent photolysis of ANPA. Radioisotope labelling experiments revealed that the enzyme was immobilized at a high surface concentration which corresponds to a closely packed monolayer of GOD. The specific activity of the immobilized enzyme was estimated to be high compared with those of other systems involving the adsorption of this enzyme. The usefulness of the present technique for fabricating biofunctional monolayer assemblies is discussed.  相似文献   
5.
An outline of the Hokkaido University PACS (HU-PACS) and 10 months experience of its clinical use are reported. It is concluded that HU-PACS is a useful clinical tool, even though some points still remain to be improved.  相似文献   
6.
MAG (metal active gas) arc welding is an important and widely used welding process that allows welding to proceed at high efficiency through appropriate selection of operating parameters, such as the welding current, welding speed, shielding gas composition, etc. Experimental determination of optimum operating parameters, however, is costly and time-consuming, although welding process simulations based on mathematical models are expected to be able to solve the problem of time and costs.  相似文献   
7.
带有平面门极和场止结构的新型IGBT器件已应用到最新研发的1200V模块上。与沟槽门极IGBT模块降低大约20%的功率损耗。  相似文献   
8.
The effect of syndiotactivity of poly(vinyl alcohol) (PVA) both on the formation and thermal stability of the complex formed in the amorphous phase of PVA films is investigated, and then a model of the complex is presented. The amount of the complex formed in syndiotacticity-rich PVA is much larger than that formed in atactic PVA under a given iodine-soaking condition, and the former complex has a higher thermal stability in the soaking solution than the latter. The complex formed in the amorphous phase is proposed to have such a structure as that in which a linear polyiodine I5? or I5? with a 3.1 A? periodicity is enveloped by four PVA segments of syndiotactic configuration with extended conformation. In this model, these four PVA chains participating in a complex are supposed to be fixed by interchain hydrogen bonds. The observed X-ray meridional intensity curve of iodinated PVA film can be explained by a series of two I5?. © 1993 John Wiley & Sons, Inc.  相似文献   
9.
The structure and optical properties of the complex formed in the crystal phase of PVA that is caused by soaking at very high iodine concentration are investigated. In the resonance Raman spectra of lightly and heavily iodinated specimens, two Raman shifts appeared at 109 and 161 cm?1. The 109 cm?1 peak due to the I mode was much stronger than the 161 cm?1 peak in a heavily iodinated specimen, whereas the peak was comparable with the 161 cm?1 peak in a lightly iodinated specimen. The complex formed in the crystal phase is identified as the I mode complex. It has an averaged iodine–iodine distance of 3.2 Å, which is different from the 3.08 Å of the I mode complex formed in the amorphous phase. The effect of KI concentration in the soaking solution on the formation of the complex is also examined. The increased KI concentration in the soaking solutions at a fixed iodine concentration increases the amount of the complex formed in the crystal phase. The change in the hydrogen-bonding state in the crystal phase with the complex formation can be evidenced by IR and NMR. © 1994 John Wiley & Sons, Inc.  相似文献   
10.
INTRODUCTION: Rapid atrial pacing in sinus rhythm may directly induce atrial flutter without provoking intervening atrial fibrillation, or initiate atrial flutter indirectly, by a conversion from an episode of transient atrial fibrillation provoked by rapid atrial pacing. The present study was performed to examine whether or not the direct induction of clockwise or counterclockwise atrial flutter was pacing-site (right or left atrium) dependent. METHODS AND RESULTS: We analyzed the mode of direct induction of atrial flutter by rapid atrial pacing. In 46 patients with a history of atrial flutter, rapid atrial pacing with 3 to 20 stimuli (cycle length = 500 - 170 ms) was performed in sinus rhythm to induce atrial flutter from 3 atrial sites, including the high right atrium, the low lateral right atrium, and the proximal coronary sinus, while recording multiple intracardiac electrograms of the atria. Direct induction of atrial flutter by rapid atrial pacing was a rare phenomenon and was documented only 22 times in 15 patients: 3, 11, and 8 times during stimulation, respectively, from the high right atrium, low lateral right atrium, and the proximal coronary sinus. Counterclockwise atrial flutter (12 times) was more frequently induced with stimulation from the proximal coronary sinus than from the low lateral right atrium (8 vs 1, P = .0001); clockwise atrial flutter (10 times) was induced exclusively from the low lateral right atrium (P = .0001 for low lateral right atrium vs proximal coronary sinus, P = .011 for low lateral right atrium vs high right atrium). CONCLUSIONS: Direct induction of either counterclockwise or clockwise atrial flutter was definitively pacing-site dependent; low lateral right atrial pacing induced clockwise, while proximal coronary sinus pacing induced counterclockwise atrial flutter. Anatomic correlation between the flutter circuit and the atrial pacing site may play an important role in the inducibility of counterclockwise or clockwise atrial flutter.  相似文献   
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