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OBJECTIVE: This study aimed to investigate the role of interleukin-12 (IL-12) and interleukin-10 (IL-10) in initiation and maintenance of intraocular inflammation. DESIGN: Case series. PARTICIPANTS: Aqueous humor and vitreous levels of IL-12 and IL-10 were measured in 22 patients with uveitis undergoing cataract surgery, paracentesis of the anterior chamber, and/or vitrectomy for diagnostic reasons, and in 4 patients with cataract only. INTERVENTION: Aqueous humor and vitreous levels of IL-12 and IL-10 were measured with specific enzyme-linked immunosorbent assays. MAIN OUTCOME MEASURES: Disease activity was correlated to IL-12 levels in the aqueous humor and the vitreous of patients with uveitis. RESULTS: Cytokine levels found in the anterior chamber and the vitreous are presented in picogram/milliliter (medium; range). The highest IL-12 levels were found in patients with active uveitis (108.5 pg/ml; 72-293 pg/ml). Interleukin-12 in patients with moderate uveitis or with their disease in remission was lower (32 pg/ml; 15-94 pg/ml) than in patients with active disease (P > 0.001) but higher than in the control group (10.5 pg/ml; 9-14 pg/ml). Interleukin-10 was detectable in only 3 of 22 patients with uveitis (12 pg/ml; 9-23 pg/ml). CONCLUSION: The authors found statistically significant differences of IL-12 levels in the various patient groups (active vs. inactive vs. control). These results support the idea that these uveitis cases represent type 1 (Th1)-T lymphocyte-mediated diseases in which IL-12 plays a pivotal role in the initiation and maintenance of the intraocular inflammation. The high levels of IL-12 in the vitreous and/or aqueous humor of the patients with uveitis suggest that susceptibility or resistance to ocular autoimmunity may be connected to a genetic predisposition to an elevated Th1 response.  相似文献   
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Summary The synthesis and thermal degradability of poly (DL-lactide) were investigated. Key factors affecting the polymer molecular weight were found to be monomer recrystallization, initiator concentration and the vacuum level during drying/sealing of the polymerization reaction ampoule. It was found that poly (DL-lactide) is thermally unstable above its melting temperature. Monomer recrystallization, polymer precipitation and a low initiator content of the polymer significantly inhibited the rate and extent of thermal degradation.  相似文献   
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Forty-three lines of barley, including ancestral (wild), landraces, Middle Eastern lines, and modern cultivars, were grown under two different sets of environmental conditions. Hordenine production in barley roots was determined at the one-leaf stage by HPLC analysis and, in two lines only, over a period of 35 days. Forty-two of the 43 lines produced significant amounts of hordenine, although there was no variation among groups. Middle Eastern lines had the highest production with 327 µg/g on a dry weight basis. Production was, however, determined more by environmental conditions during growth than by genetic factors. Hordenine production was up to seven times higher in plants grown under lower light intensities.  相似文献   
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Organizational adjustment to technological change and its impact upon human resources should be based on an understanding of employee perceptions and behavioural responses to such developments. An analytic framework which relates strategic choice to internal labour market and employee determinism is derived from the methods employed by organizational theorists and psychologists to generate a set of typologies. The framework divides variables in four classes: (1) natural selection, with minimum choice and adaptation or selection out; (2) differentiation, with high choice and high employee determinism and adaptation within constraints; (3) strategic choice, with maximum choice and adaptation by design; and (4) undifferentiated choice, with incremental choice and adaptation by chance. Useful in reconciling previously inconsistent or incompatible theories of technological change, the framework is offered as a co-ordination device to integrate the results of divergent approaches to technological adaptation studies.  相似文献   
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The Bologna process has resulted in the re- structuring of undergraduate and graduate education across Europe. This paper outlines what these changes mean for acquiring degrees in information security and how various universities have tried to respond to these demands. What is unclear at this stage is how the offering of continuous master degrees at Polytechnic and Applied Science Universities will affect the content and curriculum being taught in computer science and information security in particular. This question must be addressed since polytechnics are more industry focused and less research oriented than their university-counterparts. What seems to be clear at this stage is that continuous type master programs in computer science demand a greater level of mathematical knowledge than specialized masters. Moreover, due to the amount of credits that must be acquired, graduates of these types of programs will bring a deeper knowledge about the specialization such as, information security or malware, they acquired at university. This movement toward greater convergence in post secondary education may not have made things easier for recruiters, who are trying to hire graduates in information security or anti-virus experts. In fact, as this paper shows while the Bologna process may have eliminated the obvious differences, countless intricate and not so obvious differences have been added making it sometimes obscure for a bystander.  相似文献   
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Zusammenfassung Es wird eine Methode zur Bestimmung von Glyphosat und dessen Hauptmetabolit Aminomethylphosphonsäure (AMPA) in Trinkwasser beschrieben, die es erlaubt, den in der Schweiz geforderten Toleranzwert von 0,1 g/1 zu erreichen (Nachweisgrenze 0,02 g/l). Die Wasserprobe wird dabei direkt mit 9-Fluorenylmethyl-chloroformaat (FMOCCI) versetzt, um extrahierbare und gleichzeitig fluorescierende Derivate zu erhalten. Diese werden nach Ausschütteln mit einem organischen Lösungsmittelgemisch durch HPLC mit Fluorescenzdetektor bestimmt. In bisher 151 untersuchten Trinkwasserproben des Kantons Bern konnten weder Glyphosat noch AMPA nachgewiesen werden.
Determination of glyphosate herbicide and its main metabolite aminomethylphosphonic acid (AMPA) in drinking water by HPLC
Summary A method for the determination of glyphosate and its major metabolite aminomethylphosphonic acid (AMPA) is described. With a detection limit of 0.02 g/l, the method suitably fulfills the requirements of the Swiss legislation (tolerance value of 0.1 g/l water). The compounds are derivatized directly in the original water sample with 9-fluorenylmethyl chloroformate (FMOCCI) in order to obtain extractable and fluorescent derivatives. These are extracted with organic solvents and determined by HPLC using a fluorescence detector. Neither of the compounds could be detected in 151 tap water samples from the Canton of Berne.
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Direct foaming of colloidal suspensions is a simple and versatile approach for the fabrication of macroporous ceramic materials. Wet foams produced by this method can be stabilized by long-chain surfactants or by colloidal particles. In this work, we investigate the processing of particle-stabilized wet foams into crack-free macroporous ceramics. The processing steps are discussed with particular emphasis on the consolidation and drying process of wet foams. Macroporous alumina ceramics prepared using different consolidation and drying methods are compared in terms of their final microstructure, porosity, and compressive strength. Consolidation of the wet foam by particle coagulation before drying resulted in porous alumina with a closed-cell structure, a porosity of 86.5%, an average cell size of 35 μm, and a remarkable compressive strength of 16.3 MPa. On the other hand, wet foams consolidated via gelation of the liquid within the foam lamella led to porous structures with interconnected cells in the size range from 100 to 150 μm. The tailored microstructure and high mechanical strength of the macroporous ceramics can be of interest for the manufacture of bio-scaffolds, thermal insulators, impact absorbers, separation membranes, and light weight ceramics.  相似文献   
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The aim of the present paper is to analyze the corona charging of millimeter-size insulating disks, as well as their discharging when they are no longer exposed to the action of an external electric field. The experiments were carried out on a roll-type electrostatic laboratory separator, equipped with a wire-type corona electrode, simulating the actual charging/discharging conditions in an industrial unit. Disks of various sizes were charged on the surface of the roll electrode, then the high voltage supplied to the corona electrode was turned off and the particles were collected in a Faraday pail, connected to an electrometer. The charge measurements were performed at various time intervals from high-voltage turn-off. In this way, the charge decay could be recorded and the discharge process fully characterized. The measured data show that the discharge process depends on the nature, size, and shape of the particles, as well as on the contact conditions between the particles and the grounded roll electrode. These data could guide the design of the electrostatic separation experiments that precede any new industrial application of this technology.  相似文献   
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