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11.
Wolfgang Weber 《今日电子》2006,(5):40-41
现在,几乎所有产品都需要有唯一的ID(身份证明)用以跟踪,这一用途的标签通常是由自动的在线系统印出的。Code 39码和Code 128码作为标识产品ID的条形码已经使用很多年了,然而,当今技术的发展和质量管理的需求不可避免的对产品ID提出了更高的要求,有以下三方面的因素需要考虑。 相似文献
12.
Investigations on the Amylose Determination in High Protein Starch Source Materials, Especially Peas. The proposed utilization of amylose rich starches requires different methods of amylose determination. In addition to laboratory methods also simple tests are important to that. Because the discussed legume starches are hardly investigated, first of all the suitability of the amperometric iodine titration had to be checked. Then a more easier work was described. In the case of routine analyses a modified test procedure was compared with the method of iodine titration. 相似文献
13.
Axel Haarmann Lena Zimmermann Michael Bieber Christine Silwedel Guido Stoll Michael K. Schuhmann 《International journal of molecular sciences》2022,23(13)
In large vessel occlusion stroke, recanalization to restore cerebral perfusion is essential but not necessarily sufficient for a favorable outcome. Paradoxically, in some patients, reperfusion carries the risk of increased tissue damage and cerebral hemorrhage. Experimental and clinical data suggest that endothelial cells, representing the interface for detrimental platelet and leukocyte responses, likely play a crucial role in the phenomenon referred to as ischemia/reperfusion (I/R)-injury, but the mechanisms are unknown. We aimed to determine the role of endoglin in cerebral I/R-injury; endoglin is a membrane-bound protein abundantly expressed by endothelial cells that has previously been shown to be involved in the maintenance of vascular homeostasis. We investigated the expression of membranous endoglin (using Western blotting and RT-PCR) and the generation of soluble endoglin (using an enzyme-linked immunosorbent assay of cell culture supernatants) after hypoxia and subsequent reoxygenation in human non-immortalized brain endothelial cells. To validate these in vitro data, we additionally examined endoglin expression in an intraluminal monofilament model of permanent and transient middle cerebral artery occlusion in mice. Subsequently, the effects of recombinant human soluble endoglin were assessed by label-free impedance-based measurement of endothelial monolayer integrity (using the xCELLigence DP system) and immunocytochemistry. Endoglin expression is highly inducible by hypoxia in human brain endothelial monolayers in vitro, and subsequent reoxygenation induced its shedding. These findings were corroborated in mice during MCAO; an upregulation of endoglin was displayed in the infarcted hemispheres under occlusion, whereas endoglin expression was significantly diminished after transient MCAO, which is indicative of shedding. Of note is the finding that soluble endoglin induced an inflammatory phenotype in endothelial monolayers. The treatment of HBMEC with endoglin resulted in a decrease in transendothelial resistance and the downregulation of VE-cadherin. Our data establish a novel mechanism in which hypoxia triggers the initial endothelial upregulation of endoglin and subsequent reoxygenation triggers its release as a vasoactive mediator that, when rinsed into adjacent vascular beds after recanalization, can contribute to cerebral reperfusion injury. 相似文献
14.
This paper is an update of the overview given by Baker RC [Coriolis flowmeters: Industrial practice and published information. Flow Meas Instrum 1994;5(4):229–46]. Overviews about mass flowmetering are also given in Baker RC [Flow measurement handbook. Cambridge University Press; 2000]. Furthermore, Drahm W and Linnartz H [Coriolis-massflowmeters: State of the art review and innovations. In: Proceedings FLUCOME 2003. 2003] reported about latest innovations in Coriolis technology.
The published information of the last decade is reviewed and the conclusions of the different papers are briefly described. 相似文献
15.
Yimin Yao Alison Findlay Jessica Stolp Benjamin Rayner Kjetil Ask Wolfgang Jarolimek 《International journal of molecular sciences》2022,23(10)
Systemic sclerosis (SSc) is characterised by progressive multiple organ fibrosis leading to morbidity and mortality. Lysyl oxidases play a vital role in the cross-linking of collagens and subsequent build-up of fibrosis in the extracellular matrix. As such, their inhibition provides a novel treatment paradigm for SSc. A novel small molecule pan-lysyl oxidase inhibitor, PXS-5505, currently in clinical development for myelofibrosis treatment was evaluated using in vivo rodent models resembling the fibrotic conditions in SSc. Both lysyl oxidase and lysyl oxidase-like 2 (LOXL2) expression were elevated in the skin and lung of SSc patients. The oral application of PXS-5505 inhibited lysyl oxidase activity in the skin and LOXL2 activity in the lung. PXS-5505 exhibited anti-fibrotic effects in the SSc skin mouse model, reducing dermal thickness and α-smooth muscle actin. Similarly, in the bleomycin-induced mouse lung model, PXS-5505 reduced pulmonary fibrosis toward normal levels, mediated by its ability to normalise collagen/elastin crosslink formation. PXS-5505 also reduced fibrotic extent in models of the ischaemia-reperfusion heart, the unilateral ureteral obstruction kidney, and the CCl4-induced fibrotic liver. PXS-5505 consistently demonstrates potent anti-fibrotic efficacy in multiple models of organ fibrosis relevant to the pathogenesis of SSc, suggesting that it may be efficacious as a novel approach for treating SSc. 相似文献
16.
17.
We present a single-shot line sensor based on spectral interferometry. Light of a broadband laser source is chromatically dispersed by a grating and focused onto a line on the surface such that each focal point on this line is formed by another wavelength. The entire height profile is obtained by applying a phase evaluation algorithm to the registered interference signal, followed by a model-based approach. The sensor concept is finally verified by experimental results. 相似文献
18.
Thomas Gensch Julia M. Strassburger Wolfgang Gärtner Silvia E. Braslavsky 《Israel journal of chemistry》1998,38(3):231-236
A complex multistep model including an equilibrium was used for the first time to analyze data obtained by laser-induced optoacoustic spectroscopy (LIOAS) with bovine rhodopsin in washed membranes (T = 5–32°C). The thermal equilibrium was between bathorhodopsin, batho, and the blue-shifted intermediate (BSI), i.e., batho ⇄ BSI. This analysis considers a 14-ns intermediate detected by LIOAS at 25°C (with similar decay activation parameters as those reported for BSI in solubilized rhodopsin). The energy content of lumirhodopsin (lumi) and the structural volume difference between lumi and rhodopsin were essentially the same (Elumi. = 80 kJ/mol and ΔVlumi–rho = 40 mL/mol) for both a model based on a simple batho → BSI → lumi sequence and one including the batho ⇄; BSI equilibrium. However, the structural volume changes for the individual steps batho → BSI and BSI → lumi were markedly changed by the introduction of the equilibrium. With the rate constant for the forward reaction batho → BSI for solubilized rhodopsin determined by Hug et al. (Hug, S.J.; Lewis, W.J.; Einterz, C.M.; Thorgeirsson, T.E.; Kliger, D.S. Biochemistry, 1990 , 29, 1475–1485) the structural volume changes obtained with the equilibrium model are ΔVBSI-batho = 79 mL/mol and ΔVlumi-BSI = −44 mL/mol. The resulting batho → BSI expansion is larger than with the sequential model, and ΔVlumi-BSI is now a contraction instead of an expansion. A small expansion of 5 mL/mol is derived for the formation of batho with both models. The estimated energy content of BSI is clearly higher than the value of lumi. The structural volume changes between batho, BSI, and lumi derived from the equilibrium model correlate better than those from the simple sequential model with the chromophore transition dipole moment changes determined in the literature using linear dichroism measurements. The structural volume changes are discussed in terms of the variations upon transformation of the chromophore–protein interactions. 相似文献
19.
Using aqueous hydrogen peroxide containing 30% H2O2, solid acid catalysts were compared in their performance as catalysts for the transformation of cyclopentanone to δ-valerolactone. It could be shown that organic ion exchange resins with sulphonic acid groups providing acid functionality are promising catalysts for this reaction. The variation of several reaction parameters was studied in more detail. The obtained results were compared to investigations of zeolites and Nafion® composite materials. 相似文献
20.
The exchange of hydrogen ions for trivalent chromium species with strongly acidic exchange resins has been investigated. The experiments comprised of systems with chromium chloride and basic chromium sulphate which are applied in leather tanning. Exchange equilibria at ambient temperature were investigated as a function of pH and total chromium concentration. Exchange strongly depends on the speciation in each system. As can be expected, with chromium chloride solutions a strong preference of chromium species occurs. However, a complete pattern is found for systems with basic chromium sulphate where chromium species are not fully preferred. 相似文献