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41.
Synopsis The burbot population off the River Kyrönjoki has suffered from acidification in its reproduction area, causing a reduction of the population throughout the 1980s. During the same period of time the mean length-at-age of burbot was found to increase, with a significant increase in length-at-age for age groups 3–8 from 1979 to 1993. The length-weight relationship however was not found to have changed during this same period. The decreasing burbot population was found to influence the changed length-at-age. An increase in potential prey species population was also documented during this period of increasing length-at-age. The increased lengths were associated to the changed availability of food caused by the simultaneous fluctuations in both burbot and potential prey species populations.  相似文献   
42.
The zonation of the Furongian Alum Shale in Scandinavia, based on olenid trilobites, is reviewed and revised. The current scheme is rooted in a detailed zonation introduced in the late 1950s with subzones that subsequently have been elevated to zonal rank. Ten of these zones are difficult to recognize in all Alum Shale districts, and a revised zonation is proposed, focused on unambiguous identification throughout Scandinavia. The difficulties in recognizing zones in some districts mostly relate to biofacies differentiation. Representatives of Ctenopyge are, for instance, common in palaeo-offshore areas, whereas pelturines are rare in these settings and vice versa in palaeo-inboard settings. The following modifications of the olenid zonation are proposed: the Olenus scanicus Zone is renamed the O. scanicusO. rotundatus Zone; the Ctenopyge similis and Ctenopyge spectabilis zones are replaced by the Sphaerophthalmus modestusSphaerophthalmus angustus Zone; the Ctenopyge tumida Zone is renamed the Peltura acutidensCtenopyge tumida Zone; the Peltura scarabaeoides Subzone is restored (as a zone) and replaces the Ctenopyge bisulcata and Ctenopyge linnarssoni zones. The Parabolina heres megalops (Sub)Zone is reinstated and replaces the Peltura paradoxa Zone; the Acerocarina granulata and P. costata zones are combined as the Acerocarina granulata–Peltura costata Zone. In addition, the name Proceratopyge nathorsti–Simulolenus alpha Zone is suggested for the polymerid zone corresponding to the upper Miaolingian Agnostus pisiformis Zone. The proposed changes reduce the number of Furongian Zones to 23, allocated to six superzones. No subzones are recognized, but some zones can potentially be subdivided for improved local correlation. The stratigraphical ranges of all Furongian olenid trilobites and agnostoids described from Scandinavia are summarized.  相似文献   
43.
The characteristics of acidic polysaccharides extracted from Daucus carota L. var. sativa Hoffm were investigated and its hepatoprotective effects on alcoholic liver injury were determined in the mice model. A carrot polysaccharide (CPS-I: Carrot polysaccharide-I) with the molecular weight of 3.40×104 kDa was isolated from Daucus carota L. and purified by diethylaminoethyl-52 and Sephadex G-150 column chromatography. The components were analyzed by HPLC, which revealed that CPS-I consisted of galacturonic acid, rhamnose, xylose, arabinose, fructose, and galactose at a relative ratio of 1 : 3.16 : 1.13 : 5.53 : 3.45 : 7.76. Structural characterization analysis suggested that CPS-I was mainly composed of →6)-β-D-Galp-(1→ and →5)-α-L-Araf-(1→. The hepatoprotective effect of CPS-I was evaluated by alcoholic liver injury mice model. The results showed that the administration of CPS-I (300 mg/kg/day) alleviated the alcoholic liver injury in mice by increasing the levels of ADH and ALDH and reducing oxidative stress. CPS-I ameliorated the pathological changes of liver characterized by lipid accumulation, and reduced the number of lipid droplets.  相似文献   
44.
Through a phytochemical investigation of Abrus mollis Hance, a folk medicinal plant in China, we isolated and identified three undescribed compounds, including two flavonoids and one amides alkaloid, along with nine known from this plant. Their structures were elucidated by analyses of 1D, 2D NMR, HR-ESI-MS, ECD, and DP4+ analysis. Furthermore, we evaluated the hepatoprotective effects of all twelve compounds on D-GalN-induced Brl-3 A cells. According to the results, at a concentration of 25 μM, the cell survival rates were observed to be 71.92±0.34 %, 70.03±1.29 %, and 69.11±1.90 % for compound 2 , 4 , and 11 , respectively. Further experimental studies showed that compound 2 (EC50 5.76±0.37 μM) showed more significant protective activity than the bicyclol.  相似文献   
45.
The cornerstone of treatment for rheumatoid arthritis is low dose methotrexate (MTX), but its use is limited by concerns regarding its potential for hepatotoxicity. Allylpyrocatechol (APC), a phytoconstituent sourced from leaves of Piper betle demonstrated antioxidant, anti-inflammatory, and antiarthritic properties. The present study aimed to evaluate the combined effect of APC and MTX on limiting progression of lipopolysaccharide accelerated collagen-induced arthritis, along with reduction of MTX-induced hepatic damage. A collagen-induced arthritis (CIA) model was established by immunising Sprague-Dawley rats with bovine collagen type II (CII) and lipopolysaccharide, followed by a booster dose of CII on day 15. Rats from days 11–27 were administered APC (20?mg/kg), methotrexate (1.5?mg/kg), or a combination of MTX and APC. The combinatorial therapy of APC and MTX significantly improved the parameters of arthritis as evident from the reduction in paw oedema and arthritic score and was endorsed by radiological and histopathological changes. This combination prevented the rise in levels of proinflammatory cytokines, tumour necrosis factor (TNF-α), and interleukin 6 (IL-6). Furthermore, unlike MTX-monotherapy, the APC-MTX combination decreased the associated cachexia, splenomegaly, and oxidative stress. Importantly, the hepatic damage mediated by MTX monotherapy was effectively attenuated by the inclusion of APC. Taken together, antioxidants such as APC when combined with MTX not only potentiated the antiarthritic effect but importantly alleviated the MTX-induced hepatic damage, thus endorsing its effectiveness in preventing progression of articular diseases such as rheumatoid arthritis.  相似文献   
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47.
The effects of promethazine (PM) on different aspects of the hepatotoxic action of CCl4 in the rat were investigated with the objective of finding rapid and reliable indicators of hepatoprotective effects. The study was based on definitive histological assessment of liver damage caused by CCl4 in the presence and absence of PM: PM (78 mumol kg-1, i.p.) protected against CCl4-induced hepatic necrosis 24 h after a low dose of CCl4 (1.3 mmol kg-1) but not against a higher dose (13.0 mmol kg-1). The large increases in plasma activities of GOT, GPT and LDH produced by dosing with CCl4 were partially inhibited by the administration of PM. PM and CCl4 caused a synergistic and long-lasting decrease in body temperature (2-3 degrees C for 8-10 h). Modifying the toxicity with PM, together with a low dose of CCl4, helped to minimize secondary effects of CCl4, to clarify the sequence of toxic events, and to assess the sensitivity of some standard tests of hepatotoxicity. Simultaneous measurement of over 20 commonly used biochemical screening tests in individual animals 3 or 6 h after treatment permitted direct correlation of a wide variety of concentrations, activities and effects. For example, liver CHCl3 concentrations (as a measure of CCl4 metabolism) correlate strongly with increases in diene conjugation of microsomal lipids (as a measure of CCl4-induced lipid peroxidation); malonaldehyde production appears to be less sensitive as a measure of lipid peroxidation in vivo than diene conjugation. The changes induced in each parameter and the correlations between them are discussed with reference to the overall nature of the hepatotoxic reaction and its modification by PM.  相似文献   
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