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1.
Morinda citrifolia L. (Rubiaceae), known as noni, has a long history of traditional use in the Hawaiian and Tahitian islands. More recently, an array of commercial noni fruit juice products are gaining popularity as dietary supplements, with claims of anticancer and immunostimulant activities. The biologically active principles of noni are not fully known. In continuation of work on the isolation of markers from dietary supplements, this paper reports the isolation of three new markers, namely, 1-O-(3'-methylbut-3'-enyl)-beta-D-glucopyranose (1), 1-n-butyl-4-(5'-formyl-2'-furanyl)methyl succinate (2), and 4-epi-borreriagenin (3), together with the known iridoid glycosides asperulosidic acid (4) and deacetylasperulosidic acid (5) and a mixture of 1-n-butyl-4-methyl-2-hydroxysuccinate (6a) and 1-n-butyl-4-methyl-3-hydroxysuccinate (6b), as well as a mixture of alpha- and beta-glucopyranose from noni fruit juice obtained from Puerto Rico. The structures of compounds were based on 1H and 13C NMR, mainly 2D NMR COSY, HMQC, HMBC, and NOESY experiments, and HRMS. Furthermore, samples from fresh-squeezed noni fruit juice from Japan revealed the presence of scopoletin (7), in addition to compounds 1-6, indicating no significant differences in the marker constituents of noni collected from Atlantic and Pacific regions.  相似文献   
2.
Tropospheric ozone and black carbon (BC) contribute to both degraded air quality and global warming. We considered ~400 emission control measures to reduce these pollutants by using current technology and experience. We identified 14 measures targeting methane and BC emissions that reduce projected global mean warming ~0.5°C by 2050. This strategy avoids 0.7 to 4.7 million annual premature deaths from outdoor air pollution and increases annual crop yields by 30 to 135 million metric tons due to ozone reductions in 2030 and beyond. Benefits of methane emissions reductions are valued at $700 to $5000 per metric ton, which is well above typical marginal abatement costs (less than $250). The selected controls target different sources and influence climate on shorter time scales than those of carbon dioxide-reduction measures. Implementing both substantially reduces the risks of crossing the 2°C threshold.  相似文献   
3.
The objective of this study was to investigate the effects of the herbicide 3-amino-1,2,4-triazole (AMT) on the activities of catalase and lactate dehydrogenase (LDH) in blood (plasma and erythrocytes) and eight solid tissues of goldfish, Carassius auratus. Injection of goldfish with AMT (0.5 mg/gww AMT in 0.9% NaCl) resulted in a significant decrease in catalase activity 24 h post-injection in most tissues investigated. In white and red muscle, kidney, heart, liver, brain and erythrocytes the activity of catalase decreased by 61%, 69%, 64%, 48%, 40%, 27% and 26%, respectively, in comparison to the values seen in animals injected with physiological saline (0.9% NaCl). However, the activity of LDH decreased only in red muscle (by 19%) after AMT injection, whereas in plasma it increased by 137%. Protein carbonyl levels, a measure of oxidative damage to proteins, did not change in plasma in goldfish injected with AMT and total hemoglobin levels in AMT-injected fish, although lower compared with uninjected controls, did not differ from values in saline-injected controls. It is proposed that catalase activity in erythrocytes and white muscle might be usefully developed as a potential marker for fish intoxication by aminotriazole and other related herbicides.  相似文献   
4.
引进小麦种质材料的高分子量谷蛋白亚基分析   总被引:2,自引:0,他引:2  
为了有效利用多年来引自俄罗斯及中亚地区的小麦资源,了解引进材料的遗传基础,特别是品质基础,采用SDS-PAGE技术对102份小麦材料的高分子量谷蛋白亚基(HMW-GS)组成进行了分析。结果表明,参试材料中共检测到11种HMW-GS类型,Glu-A1位点上有1、2*、Null,Null位点相对比较多,为40.20%;Glu-B1位点上有7、7+8、7+9、6+8、17+18,以7+9为主要类型(59.80%);Glu-D1位点有2+12、2+12’、5+10三种类型,其中5+10所占比例为51.96%。参试材料共检测到16种亚基组合,其中"Null,7+9,2+12"所占比例较大,为25.5%。值得一提的是,参试材料中品质评分为10分的材料有22个,9分的有29个。这些材料有可能会成为比较有价值的品质改良中间材料。  相似文献   
5.
Sexually mature males (BW?=?1600?±?150 g and TL?=?235?±?30 mm) of northern pike (Esox lucius L.) were randomly selected from a pond to record changes in their sperm quality parameters (spermatozoa morphology, sperm volume, density, and motility parameters) during the spawning season. The morphological and motility parameters changed significantly during the reproductive season with following trends. Only, head width was not changed during the spawning season. The longest spermatozoa and its flagellar length were found at the middle of spawning period (TL?=?38.24?±?0.37 μm and 35.14?±?0.26 μm) and shortest at the beginning of spawning period (TL?=?34.81?±?0.29 μm and 32.53?±?0.18 μm). Other morphological characters were always the lowest at the beginning of spawning period. Sperm volume was changed from 0.33?±?0.3 ml in February, 0.43?±?0.2 ml in March to 0.24?±?0.1 ml in April, and density from 16.2?±?0.2?×?109 spermatozoa ml?1 in February, 19.4?±?0.2?×?109 spermatozoa ml?1 in March to 4.8?±?0.2?×?109 spermatozoa ml?1 in April. Same sperm velocity was observed in all spawning terms at 10 and 20 s after activation. Higher velocity was found at 30 and 40 s after activation in sperm collected at the middle and the end of spawning period. Significantly, higher percentage of motile sperm was observed at 20, 30, and 40 s after activation in sperm sampled at the end of spawning period. This study supports the hypothesis that longer spermatozoa swim faster.  相似文献   
6.
European natural mountain Norway spruce (Picea abies) forests are currently subject to extensive disturbances. An improved understanding of the self-regulated regenerative capacity of this forest type is therefore needed. We used the last remnant of natural mountain Norway spruce forests in central northwestern Europe (BNF Brocken natural forest), to analyze (1) the diversity of structure and age distribution of the tree population and (2) the effect of disturbances on self-regulated tree regeneration over the last 264 years. To this end, we combined an assessment of stand structure with dendrochronological investigations and a review of disturbance history. We hypothesized that BNF exhibits a high diversity of tree ages and dimensions and that recruitment and survival of tree regeneration were largely independent from disturbances. BNF showed a high structural and age diversity. Disturbances exhibited no regular temporal pattern. Their effect on tree regeneration was rather complex and changed with observation period. Impeding and facilitating effects of past disturbances on recruitment were significant from 1736 to 1910. From 1911 until 2000, recruitment decoupled from preceding disturbances. Subsequent disturbances facilitated survival of established trees from 1736 to 1820, while afterward no significant influence could be proved. Our study showed that in the course of self-regulated development the tree population of BNF has gradually acquired, or maintained, a diverse structure. Disturbances served as an important driver of diversification. We concluded that increasing deadwood availability and limiting browsing are the key to securing immediate regeneration.  相似文献   
7.
The goal of our study was to identify pharmaceuticals, their potential sources and consumption level in two different socioeconomic and geographical regions??Bordeaux, France and Kharkiv, Ukraine. These substances were monitored in rivers water during contrasted seasonal conditions with application of passive samplers. The 21 pharmaceuticals (psychiatric drugs: alprazolam, amitriptyline, diazepam, fluoxetine, nordiazepam, carbamazepine, bromazepam; analgesics: aspirin, paracetamol; broncholidator: clenbuterol, salbutamol, terbutaline; non-steroidal anti-inflammatory drug: diclofenac, ibuprofen, ketoprofen, naproxen; lipid regulator: gemfibrozil; stimulants: caffeine, theophylline) were identified in sites upstream and downstream of urban areas and discharge of wastewaters. Caffeine, carbamazepine, and diclofenac were relatively abundant into the surface water and could be considered as potential anthropogenic markers of wastewater discharges into rivers. A mass balance modeling has been applied to calculate approximate consumption rates for carbamazepine, diclofenac, and caffeine in both regions to assess socio-economic factors linked with pharmaceuticals behavior.  相似文献   
8.
European Journal of Forest Research - Process-based forest models are important tools for predicting forest growth and their vulnerability to factors such as climate change or responses to...  相似文献   
9.
Copper is an essential element, but at high concentrations, it is toxic for living organisms. The present study investigated the responses of goldfish, Carassius auratus, to 96 h exposure to 30, 300, or 700 μg L?1 of copper II chloride (Cu2+). The content of protein carbonyls was higher in kidney (by 158%) after exposure to 700 mg L?1 copper, whereas in gills, liver, and brain, we observed lower content of protein carbonyls after exposure to copper compared with control values. Exposure to copper resulted in increased levels of lipid peroxides in gills (76%) and liver (95–110%) after exposure to 300 and 700 μg L?1 Cu2+. Low molecular mass thiols were depleted by 23–40% in liver and by 29–67% in kidney in response to copper treatment and can be used as biomarkers toxicity of copper. The activities of primary antioxidant enzymes, superoxide dismutase and catalase, were increased in liver as a result of Cu2+ exposure, whereas in kidney catalase activity was decreased. The activities of glutathione-related enzymes, glutathione peroxidase, glutathione-S-transferase, and glutathione reductase were decreased as a result of copper exposure, but glutathione reductase activity increased by 25–40% in liver. Taken together, these data show that exposure of fish to Cu2+ ions results in the development of low/high intensity oxidative stress reflected in enhanced activities of antioxidant and associated enzymes in different goldfish tissues.  相似文献   
10.
Both cats and dogs belong to animals with the same type of limb support but have different nature of movement. Despite belonging to digitigrade animals, cats and dogs have a different nature of motion. While moving, the medial joint surface in cats and lateral surface in dogs carry the larger pressure. The aim of the study was to compare the similar surfaces of the cat's and dog's tarsal joint capsule and to detect differences in its histostructure and vascularisation. For the study, we used the capsule of the tarsal joint of five cats and five dogs dissected with accordance to anatomical surfaces. Sections of the capsule joint were stained with haematoxylin–eosin. The sections were examined with a microscope at magnification ×250 and ×400. The statistical analysis of the results was done using Student's t test. During the research, a difference in histostructure and vascularisation of tarsal joint capsule in cats and dogs on respective surfaces were found. The medial surface of the tarsal joint capsule was the most saturated with hemomicrocirculatory bed structures in cats, whereas this was the lateral surface in dogs. The most active metabolic processes also take place in these areas of the joint capsule, which is important to know when prescribing therapeutic procedures and determining an optimal surgical access.  相似文献   
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