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371.
Launay P Cheng H Srivatsan S Penner R Fleig A Kinet JP 《Science (New York, N.Y.)》2004,306(5700):1374-1377
TRPM4 has recently been described as a calcium-activated nonselective (CAN) cation channel that mediates membrane depolarization. However, the functional importance of TRPM4 in the context of calcium (Ca2+) signaling and its effect on cellular responses are not known. Here, the molecular inhibition of endogenous TRPM4 in T cells was shown to suppress TRPM4 currents, with a profound influence on receptor-mediated Ca2+ mobilization. Agonist-mediated oscillations in intracellular Ca2+ concentration ([Ca2+]i), which are driven by store-operated Ca2+ influx, were transformed into a sustained elevation in [Ca2+]i. This increase in Ca2+ influx enhanced interleukin-2 production. Thus, TRPM4-mediated depolarization modulates Ca2+ oscillations, with downstream effects on cytokine production in T lymphocytes. 相似文献
372.
The antimicrobial and cytotoxic activities of six lignans isolated from the core and bark acetone extracts of Hibiscus cannabinus have been investigated. Two compounds (2 and 3) showed strong cytotoxic activity against HeLa, Hep-2 and A-549 cell lines while compound 5 showed moderate activity on HeLa cells when they were in advanced stage of cellular division. The compounds did not exhibit antimicrobial activity. 相似文献
373.
P Reinhold A Langenberg G Becher M Rothe 《Berliner und Münchener tier?rztliche Wochenschrift》1999,112(6-7):254-259
Collection of exhaled condensate (freezing of expired air under conditions of spontaneous breathing) is a non-invasive method permitting the collection of material originating from the lung and the lower respiratory tract so that it can be used for diagnostic examinations. In order to be able to evaluate the diagnostic evidence of exhaled condensate samples in cases of respiratory disease of the calf, leukotriene B4 (LTB4) in bovine exhaled condensate was determined. The influence of the breathing pattern and body temperature on the quantity of condensate to be collected was tested in a total of 49 exhaled condensate samples. It became obvious that the exhaled condensate quantity obtained per time unit is dependent on the ventilation volume per time unit (minute volume). In exhaled condensate samples from 35 clinically healthy calves, LTB4 concentrations of less than 250 pg/mL exhaled condensate were detected. A total of 14 exhaled condensate samples from 7 calves was analyzed before and after experimental respiratory infection with Pasteurella multocida D. In parallel to the analysis of LTB4 in exhaled condensate, the lung function of the calves was examined by means of impulse oscilloresistometry. The increase of LTB4 in the exhaled condensate post infection correlated significantly (p < or = 0.05) with decreases of respiratory reactance. The determination of LTB4 concentrations in exhaled condensate seems to be suitable, in principle, for the detection of inflammations in the respiratory system of the calf. Further studies are needed for the evaluation of the diagnostic validity of the method. 相似文献
374.
The influence of the soil mineral phase on organic matter storage was studied in loess derived surface soils of Central Germany. The seven soils were developed to different genetic stages. The carbon content of the bulk soils ranged from 8.7 to 19.7 g kg—1. Clay mineralogy was confirmed to be constant, with illite contents > 80 %. Both, specific surface area (SSA, BET‐N2‐method) and cation exchange capacity (CEC) of bulk soils after carbon removal were better predictors of carbon content than clay content or dithionite‐extractable iron. SSA explained 55 % and CEC 54 % of the variation in carbon content. The carbon loadings of the soils were between 0.57 and 1.06 mg C m—2, and therefore in the ”︁monolayer equivalent” (ME) level. The increase in SSA after carbon removal (ΔSSA) was significantly and positively related to carbon content (r2 = 0.77). Together with CEC of carbon‐free samples, ΔSSA explained 90 % of the variation in carbon content. Clay (< 2 μm) and fine silt fractions (2—6.3 μm) contained 68—82 % of the bulk soil organic carbon. A significantly positive relationship between carbon content in the clay fraction and in the bulk soil was observed (r2 = 0.95). The carbon pools of the clay and fine silt fractions were characterized by differences in C/N ratio, δ13C ratio, and enrichment factors for carbon and nitrogen. Organic matter in clay fractions seems to be more altered by microbes than organic matter in fine silt fractions. The results imply that organic matter accumulates in the fractions of smallest size and highest surface area, apparently intimately associated with the mineral phase. The amount of cations adhering to the mineral surface and the size of a certain and specific part of the surface area (ΔSSA) are the mineral phase properties which affect the content of the organic carbon in loess derived arable surface soils in Central Germany most. There is no monolayer of organic matter on the soil surfaces even if carbon loadings are in the ME level. 相似文献
375.
Essential oil of Aloysia triphylla in Nile tilapia: anaesthesia,stress parameters and sensory evaluation of fillets 下载免费PDF全文
Rafael Rivas Teixeira Renilde Cordeiro de Souza Artur Cedraz Sena Bernardo Baldisserotto Berta Maria Heinzmann Ricardo David Couto Carlos Eduardo Copatti 《Aquaculture Research》2017,48(7):3383-3392
The optimum concentration of anaesthetic used to facilitate fish handling can be determined based on induction and recovery time, among other factors. This study aimed to evaluate the effectiveness of the essential oil of Aloysia triphylla (EOAT) as an anaesthetic in the handling of Nile tilapia juveniles. Nile tilapias exemplars were immersed at 0 (control group), 10, 20, 30, 40, 80, 150, 300 and 450 μL L?1 EOAT to evaluate sedation, anaesthesia and recovery time. The stress response was evaluated by the determination of plasma glucose, cortisol, lactate and paraoxonase levels in anaesthetized (300 μL L?1 EOAT) and non‐anaesthetized fish. Fillets from both groups were evaluated for organoleptic characteristics (taste and odour). Concentrations of 80–450 μL L?1 EOAT were effective in inducing anaesthesia. There was a significant reduction in plasma cortisol levels one hour after handling in individuals anaesthetized with 300 μL L?1 EOAT compared to the control group. Tasters did not detect differences in fillet taste and odour between fish exposed and not exposed to EOAT. A concentration of 300 μL L?1 EOAT is recommended for handling Nile tilapia because it presents good anaesthetic induction and recovery times, causes a reduction in plasma cortisol levels one hour after handling and does not affect the taste or odour of the fillets. 相似文献
376.
Matthias Schaber Lasse Marohn Christoph Petereit Jan P. Schroeder Karsten Zumholz Reinhold Hanel 《Fisheries Science》2011,77(5):757-764
In recent years, thicklip grey mullet Chelon labrosus has shown increasing expansion of its native habitats in the north-eastern Atlantic into northerly adjacent areas including
the North Sea and the brackish Baltic Sea. Despite the regular annual and seasonal occurrence of C. labrosus in the western Baltic during the warm months, nothing is known of the origin or whereabouts of the mullet during the cold
season. As different possible migration scenarios can be considered, we performed otolith microchemistry analyses on specimens
from the western Baltic Sea to identify the origin of this nonindigenous species. Comparison with North Sea samples revealed
common habitat preferences and underlined the highly euryhaline nature of C. labrosus in different recently occupied habitats. Occasional fluctuations of Sr/Ca ratio along the growth axis suggest periodical
migration between waters of different salinities but did not reveal distinct migration pathways. 相似文献
377.
One nonwaxy (covered) and two waxy (hull-less) barleys, whole grain and commercially abraded, were milled to break flour, reduction flour, and the bran fraction with a roller mill under optimized conditions. The flour yield range was 55.3–61.8% in whole grain and increased by 9–11% by abrasion before milling. Break flours contained the highest starch content (≤85.8%) independent of type of barley and abrasion level. Reduction flours contained less starch, but more protein, ash, free lipids, and total β-glucans than break flours. The bran fraction contained the highest content of ash, free lipids, protein, and total β-glucans but the lowest content of starch. Break flours milled from whole grain contained 82–91% particles <106 μm, and reduction flours contained ≈80% particles <106 μm. Abrasion significantly increased the amount of particles <38 μm in break and reduction flours in both types of barley. Viscosity of hot paste prepared with barley flour or bran at 8% concentration was strongly affected by barley type and abrasion level. In cv. Waxbar, the viscosity in bran fractions increased from 428 to 1,770 BU, and in break flours viscosity increased from 408 to 725 BU due to abrasion. Sugar snap cookies made from nonwaxy barley had larger diameter than cookies prepared from waxy barley. Cookies made from break flours were larger than those made from reduction flours, independent of type of barley. Quick bread baked from nonwaxy barley had a loaf volume similar to that of wheat bread, whereas waxy barley bread had a smaller loaf volume. Replacement of 20% of wheat flour by both waxy and nonwaxy barley flour or bran did not significantly affect the loaf volume but did decrease the hardness of quick bread crumb. 相似文献