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111.
Electron microscope observations were made of rat peroneal nerve after crushing using intravenously injected horseradish peroxidase (HRP) as a tracer protein to indicate changes in vascular permeability. At 1/2 h and 2 d after the crush there was gross leakage of HRP from damaged capillaries at the site of injury but none from vessels above or below this. Ultrastructurally vessels at the site of crush showed broken and separated endothelial cells. Proximally and distally there was little abnormal in the vessel walls; vesicles containing HRP were absent and tight-junctions between cells remained intact. Twenty-one days after the crush, leakage of HRP was found both at the site of crush and along the distal segment. The only change in vessel walls was an obvious increase in vesicles filled with HRP. Tracer was also found both in perivascular locations and throughout the endoneurial space.  相似文献   
112.
Modern ionising photon dosimetry is essentially entirely based upon gas-filled cavity determinations. For photons, ion chamber response is largely independent of photon energy almost perfectly transforming absorbed dose in the gas to the surrounding media. Absolute uncertainties are <1-2%. For fast neutron dosimetry, this is certainly not the case. Interpretation of the response of the cavity filling material, usually a gas, to the charged particle spectrum induced in the walls and interacting with the cavity gas is fraught with uncertainties. Despite these challenges, gas filled cavities surrounded by various mixtures, compounds and elements, have proved to be essential for integral determinations of the indirectly ionising neutrons, generating dosimetric quantities, such as kerma and absorbed dose. The transformation from gas response to wall dose is material dependent and varies with neutron energy. This study discusses recent advances in cavity response interpretation using the results from complex nuclear modelling of microscopic cross sections as well as estimates of secondary particle production enabling much improved cavity gas-to-wall media conversion factors.  相似文献   
113.
This paper introduces three approaches to using Evolutionary Computation (EC) in Music (namely, engineering, creative and musicological approaches) and discusses examples of representative systems that have been developed within the last decade, with emphasis on more recent and innovative works. We begin by reviewing engineering applications of EC in Music Technology such as Genetic Algorithms and Cellular Automata sound synthesis, followed by an introduction to applications where EC has been used to generate musical compositions. Next, we introduce ongoing research into EC models to study the origins of music and detail our own research work on modelling the evolution of melody.  相似文献   
114.
We describe five patients with acute pancreatitis in whom acute renal failure developed in the absence of hypotension. Pancreatitis was diagnosed clinically, with mean serum and urinary amylase levels of 766 +/- 197 (SE) and 2,378 +/- 572 units/100 ml, respectively. Acute renal failure developed within 24 hours after admission in all patients. It was manifested by oliguria, elevated levels of serum creatinine (mean, 6.9 +/- 1.1 mg/100 ml) and BUN (105 +/-28 mg/100 ml); a urinary sodium level of 72.0 +/- 6.6 mEq/liter; and isosmotic urine (355 +/- 31 mOsm/liter). The mean uric acid level was 18.6 +/- 1.6 mg/100 ml. Blood pressure was recorded frequently, and the lowest mean diastolic pressure was 96 +/- 6 mm Hg. The duration of the oliguric phase of acute renal failure was 8.2 +/- 1.7 days, and all patients recovered from both the acute pancreatitis and acute renal failure. In summary, acute pancreatitis, per se, can precipitate acute renal failure. It occurs early in the course of the pancreatitis, and extreme hyperuricemia is frequent finding that does not adversely affect the recovery of renal function.  相似文献   
115.
116.
Emergent textural contours, the perceptual effect seen during continuous rotation of symmetrical arrays of uniform pattern elements, provide a unique source of visual feedback for eye movements and resolutional states and have potential for use as a new clinical tool. The phenomenon is produced by a combination of factors including the effects of visual persistence and differential resolution. A total of 28 subjects including 17 normals, 4 nystagmus, 4 oculomotor dysfunction, and 3 accommodative facility cases were shown an emergent textural contour with an instrument (the Goldrich Contour Rotator) for its display. Subjects were enabled to monitor their own eye movements and accommodative training. Nystagmus subjects were provided with a continuous source of visual input reflecting their ocular oscillations and a determination of the null point of nystagmus was made with the instrument.  相似文献   
117.
1,n-Dihaloalkanes can be photochemical precursors of n-haloalkyl and -allyl radicals and cations, which are generated via one-photon processes. Time-resolved techniques have provided considerable information on the structures and reactivity of these intermediates. Low-temperature matrix isolation, two-laser two-color, laser-drop, and laser-jet photolysis techniques are powerful tools to photolyze haloalkyl radicals and to generate carbenes or biradicals via two-photon processes.  相似文献   
118.
This work is concerned with understanding the influence of reinforcement mechanisms of carbon nanotubes (CNTs) on mechanical, wear, and fatigue tests on an Aluminium-Silicon (AlSi) alloy. The reinforcement mechanism is presented through the observation of fracture morphology of the different tests. Results of mechanical properties, fatigue life performance, and wear loss is presented and discussed. It is shown that the CNTs reinforcement effect is active simultaneously in all previous properties and the reinforcement physical mechanism seems to be essentially due to a reinforcement effect of the interface that seems to be similar in all mentioned mechanical solicitations.  相似文献   
119.
Rosemary (dried leaves ofRosmarinus officinalis L.) added to cooked meat balls (minced pork) was found to retard the formation of warmed over flavour (WOF) during chill storage. The spice was added to pork meat (Longissimus dorsi) balls in an amount acceptable for the product, as evaluated by a sensory panel (0.05% of total weight). After cooking (water bath, internal temperature 80°C), the meat balls were packed using five atmosphere packaging conditions: (i) air; (ii) 5% O2/95% N2; (iii) 3% O2/97% N2; (iv) 1% O2/99% N2; and (v) 100% N2. During chill storage (5°C), the sensory quality of the reheated meat balls was evaluated by a trained sensory panel, and lipid oxidation was followed by measurement of thiobarbituric acid reactive substances (TBARS). The combination of decreased O2 atmosphere in the packages and addition of rosemary resulted in a significantly (p<0.05) lower amount of TBARS and a significantly (p<0.05) better sensory score.
Gemeinsamer Effekt von Rosmarin (Rosmarinus officinalis L.) und Verpackung in modifizierter Atmosphäre auf den Aufwärmegeschmack (WOF) von wärmebehandeltem, gehacktem Schweinefleisch
Zusammenfassung Rosmarin (getrocknete Blätter vonRosmarinus officinalis L.), erwärmten Fleischklößen (gehacktes Schweinefleisch) zugesetzt, hinderte die Entwicklung des Aufwärmgeschmacks (warmed over flavour) während der Kühllagerung. Das Gewürz wurde den aus Schweinefleisch (Longissimus dorsi) hergestellten Fleischklößen in einer für das Produkt akzeptablen Menge zugegeben, beurteilt von einem sensorischen Panel (0.05% des Totalgewichtes). Nach der Wärmebehandlung (Wasserbad, Zentrum-Temperatur 80°C) wurden die Fleischklöße in fünf unterschiedlichen und kontrollierten Atmosphären wie folgt verpackt: (i) Luft; (ii) 5% O2/95% N2; (iii) 3% O2/97% N2; (iv) 1% O2/99% N2 und (v) 100% N2. Während der Kühllagerung (5°C) wurde die sensorische Qualität der wiedererwärmten Fleischklöße von einem geschulten Panel beurteilt und die Lipid-Oxidation durch Messung der Thiobarbitursäure-reaktiven Substanzen (TBARS) beobachtet. Die Kombination von ermäßigtem Sauerstoffgehalt in den Verpackungen mit der Zugabe von Rosmarin ergab eine signifikant (p<0.05) niedrigere Menge TBARS wie auch signifikant (p<0.05) bessere Punkte in der sensorischen Beurteilung.
  相似文献   
120.
The 20-kDa protein gene is androgen regulated in rat ventral prostate. Intron 1 contains a 130-base pair complex response element (D2) that binds androgen (AR) and glucocorticoid receptor (GR) but transactivates only with AR in transient cotransfection assays in CV1 cells using the reporter vector D2-tkCAT. To better understand the function of this androgen-responsive unit, nuclear protein interactions with D2 were analyzed by DNase I footprinting in ventral prostate nuclei of intact or castrated rats and in vitro with ventral prostate nuclear protein extracts from intact, castrated, and testosterone-treated castrated rats. Multiple androgen-dependent protected regions and hypersensitive sites were identified in the D2 region with both methods. Mobility shift assays with 32P-labeled oligonucleotides spanning D2 revealed specific interactions with ventral prostate nuclear proteins. Four of the D2-protein complexes decreased in intensity within 24 h of castration. UV cross-linking of the androgen-dependent DNA binding proteins identified protein complexes of approximately 140 and 55 kDa. The results demonstrate androgen-dependent nuclear protein-DNA interactions within the complex androgen response element D2.  相似文献   
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