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1.
For application of n-3 fatty acids, distribution of the fatty acid compositions of different parts of (head, tail, fins and skin = HTFS, liver, viscera and muscle tissue) five commercially important fish species from the Persian Gulf (Scomberomorus commersoni, Thunnus tonggol, Euthynnus affinis, Scomberomorus guttatus and Dussumieria acuta) as good sources of n-3 PUFA were studied. The richest source of n-3 were HTFS in S. guttatus and S. commersoni, liver in S. guttatus, total body of D. acuta, liver of E. affinis and T. tonggol, followed by viscera of E. affinis. The content of these fatty acids were the same in viscera of tonggol, liver of S. commersoni, and HTFS of E. affinis. Moreover, muscle of E. affinis and HTFS of T. tonggol and also muscle of S. guttatus and T. tonggol had the same n-3 contents as the viscera of S. commersoni. So, it was concluded that HTFS and viscera (which are discarded as residues) are as useful as muscle and liver and can be a source of economically available n-3 PUFA. Muscle had the lowest proportion of n-3 in E. affinis, T. tonggol, and S. guttatus in comparison with other organs of these fish species. The highest n-3:n-6 ratio was observed in D. acuta. Finally, the cluster analysis showed that with respect to n-3 and other PUFA contents, HTFS of S. commersoni and D. acuta with S. guttatus on the one hand, and HTFS of T. tonggol and E. affinis on the other hand were similar to each other. In addition, viscera of S. commersoni and S. guttatus were similar followed by T. tonggol and different from E. affinis and D. acuta. In the case of muscle, T. tonggol and S. guttatus had good similarity followed by E. affinis and had no significant similarity with S. commersoni and D. acuta. With regard to liver, the highest similarity was observed between T. tonggol and E. affinis followed by D. acuta and S. guttatus, while S. commersoni did not show similarity with the others.  相似文献   

2.
目的建立心宝丸、心力丸和活心丸微生物限度检查方法;研究活心丸在不同浓度2,3,5-三苯基氯化四氮唑(TTC)琼脂平板上细菌数测定的影响。方法测定心宝丸、心力丸、活心丸对5种试验菌的回收率;活心丸分别在0.0005%、0.001%、0.002%、0.003%TTC浓度营养琼脂平板测定细菌数,选用适宜TTC浓度营养琼脂平板测定活心丸对大肠埃希菌、金黄色葡萄球菌、枯草芽孢杆菌的回收率;并对控制菌(大肠埃希菌、大肠菌群、沙门菌)检查方法进行验证。结果心宝丸、心力丸对5种菌的回收率均大于70%,活心丸对白色念珠菌、黑曲霉的回收率也均大于70%,无抑菌作用,可采用常规方法进行微生物限度检查;活心丸使用0.001%TTC营养琼脂平板测出细菌数(控制菌落蔓延生长),测回收率均大于70%,可采用该方法对该药品进行微生物限度检查;其它均符合要求。结论确立了三种中药成方制剂微生物限度检查方法。  相似文献   

3.
Three European julid species, Cylindroiulus boleti, Leptoiulus trilineatus, and Megaphyllum bosniense, secrete mixtures of up to 12 different quinones. The major components in these species are 2-methoxy-3-methyl-1,4-benzoquinone and 2-methyl-1,4-benzoquinone. 2-Methoxy-5-methylhydroquinone is detected for the first time in the Class Diplopoda. 2-Hydroxy-3-methyl-1,4-benzoquinone, 2,3-dimethoxyhydroquinone, 2-methyl-3,4-methylendioxyphenol, and 2,3-dimethoxy-5-methylhydroquinone are registered for the first time in representatives of the family Julidae. The similar chemical composition of defense secretions in all analyzed European julids and Pacific spirobolids supports the idea of the chemical consistency of defensive compounds in juliform millipedes.  相似文献   

4.
王翔 《当代化工》2003,32(3):140-141,144
将炼厂污水处理过程中的“三泥”经预处理、混凝、离心脱水处理后作为焦化装置部分原料参加反应进行处理,以产品形式出装置,实现了变废为宝。通过此次的研究,为炼厂污水处理过程中“三泥”的治理提供了切实可行的技术路线和宝贵的经验,解决了炼油化工企业“三泥”治理的难题。  相似文献   

5.
6.
李冬梅梅 《农药》1998,37(3):22-24
1996和1997年用1%灭虫灵(阿维菌素)乳油进行了防治甘蓝蚜、桃蚜、苹果黄蚜的田间药效试验.结果表明,该药对上述三种蚜虫均有较好防效.1%灭虫灵乳油1000倍和2O00倍液在药后7天均达到90%以上的防效,持效期在14天以上,且对作物安全.  相似文献   

7.
8.
在氮气氛和不同的加热速率下对三种木材(马尾松、棉杆和杉木)进行了热重分析.同时研究了碳酸钠对这三种木材热解的催化效应.运用Popescu法从22种动力学机理函数中寻求裂解的最概然机理函数并计算裂解的动力学参数.结果表明,Zhuralev,Lesokin and Tempelmen(Z-L-T)方程为最概然机理函数.根据Z-L-T方程计算的动力学参数表明,在裂解的低转化率范围,碳酸钠可以降低表观裂解活化能,而在裂解的高转化率范围,碳酸钠可以增加表观裂解活化能.根据木材的结构成分对碳酸钠的催化行为进行了分析.  相似文献   

9.
10.
Frontal gland contents of soldiers of three Prorhinotermes species, Prorhinotermes canalifrons, Prorhinotermes inopinatus, and Prorhinotermes simplex, consisted of two groups of compounds: nitroalkenes and sesquiterpene hydrocarbons. Analysis by gas chromatography-mass spectrometry revealed (E)-1-nitropentadec-1-ene as the major component of the glands with mean values of 152, 207, and 293 μg/individual for P. canalifrons, P. inopinatus, and P. simplex, respectively. Four other 1-nitroalkenes (C13, C14, C16, and C17), and two nitrodienes (C15 and C17) were also detected in the three species. The C17:1 nitroalkene was identified as (E)-1-nitroheptadec-1-ene. The sesquiterpene composition of the gland was species-specific: P. simplex contained (3Z,6E)-α-farnesene (mean of 39 μg/individual), while P. canalifrons and P. inopinatus contained the same compound (means of 0.5 and 1.5 μg/individual, respectively) as well as the (3E,6E) isomer (means of 1.8 and 0.7 μg/individual, respectively). Two other sesquiterpenes, trans-β-bergamotene and (Z)-γ-bisabolene, were also found in low quantities in the frontal gland of P. canalifrons.  相似文献   

11.
Botrytis squamosa, Botrytis aclada, and Sclerotium cepivorum are three fungal species of the family Sclerotiniaceae that are pathogenic on onion. Despite their close relatedness, these fungi cause very distinct diseases, respectively called leaf blight, neck rot, and white rot, which pose serious threats to onion cultivation. The infection biology of neck rot and white rot in particular is poorly understood. In this study, we used GFP-expressing transformants of all three fungi to visualize the early phases of infection. B. squamosa entered onion leaves by growing either through stomata or into anticlinal walls of onion epidermal cells. B. aclada, known to cause post-harvest rot and spoilage of onion bulbs, did not penetrate the leaf surface but instead formed superficial colonies which produced new conidia. S. cepivorum entered onion roots via infection cushions and appressorium-like structures. In the non-host tomato, S. cepivorum also produced appressorium-like structures and infection cushions, but upon prolonged contact with the non-host the infection structures died. With this study, we have gained understanding in the infection biology and strategy of each of these onion pathogens. Moreover, by comparing the infection mechanisms we were able to increase insight into how these closely related fungi can cause such different diseases.  相似文献   

12.
Ozone decomposition kinetics are investigated together with the influence of energy input to an ozone generator. Decomposition is considered in a solid bed reactor, a gas phase reactor and a bubbling reactor. Ozone is produced at the same concentration and gas flow rate using two methods: 1) from the generator at a higher power giving higher ozone concentration, then ozone is diluted by oxygen before entering the decomposition reactor, and 2) at a lower power without dilution.  相似文献   

13.
殷光发  许燕 《山东化工》2022,51(1):106-110,116
以文献调研的方式,查阅了近十年有关蔷薇科植物不同部位提取物的化学成分以及药理作用的文献,并进行归纳总结,过去对于蔷薇科植物的研究主要集中在绿化、护肤和食用价值上,近年来随着对蔷薇科植物的研究其药用价值和营养价值也逐渐被人们关注和重视,蔷薇科有着诸多生物活性,蕴含的化学成分有着良多的药理作用,具有很高的研究前景.  相似文献   

14.
The D2 subunit dopamine receptor represents a key factor in modulating dopamine release. Moreover, the investigated radiopharmaceutical ligands used in positron emission tomography imaging techniques are known to bind D2 receptors, allowing for dopaminergic pathways quantification in the living human brain. Thus, the biophysical characterization of these radioligands is expected to provide additional insights into the interaction mechanisms between the vehicle molecules and their targets. Using molecular dynamics simulations and QM calculations, the present study aimed to investigate the potential positions in which the D2 dopamine receptor would most likely interact with the three distinctive synthetic 11C-labeled compounds (raclopride (3,5-dichloro-N-[[(2S)-1-ethylpyrrolidin-2-yl]methyl]-2-hydroxy-6-methoxybenzamide)—RACL, FLB457 (5-bromo-N-[[(2S)-1-ethylpyrrolidin-2-yl]methyl]-2,3-dimethoxybenzamide)—FLB457 and SCH23390 (R(+)-7-Chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine)—SCH)), as well as to estimate the binding affinities of the ligand-receptor complexes. A docking study was performed prior to multiple 50 ns molecular dynamics productions for the ligands situated at the top and bottom interacting pockets of the receptor. The most prominent motions for the RACL ligand were described by the high fluctuations of the peripheral aliphatic -CH3 groups and by its C-Cl aromatic ring groups. In good agreement with the experimental data, the D2 dopamine receptor-RACL complex showed the highest interacting patterns for ligands docked at the receptor’s top position.  相似文献   

15.
Investigations on the cellular uptake of hexadecylphosphocholine   总被引:1,自引:1,他引:0  
The uptake of [(9,10)-3H]hexadecylphosphocholine (HePC) in six tumor cell lines was studied. All cell lines incorporated HePC in similar amounts, with the exception of the epidermoid cancer cell line KB, which took up higher amounts of HePC. The uptake of HePC at 37°C was shown to be time and concentration dependent. At 20°C, uptake was drastically reduced and at 4°C it was blocked completely. Binding of HePC, at 4°C, was not saturable at concentrations between 5 βg/mL (11.8 μM) and 100 μg/mL (235.3 μM), indicating that cell surface binding is not receptor-mediated. Furthermore, the effects of inhibitors of endocytosis were investigated. We observed a pronounced inhibitory effect by monensin and cytochalasin B. Colchicine was somewhat less effective whereas chloroquine was almost without effect. From these data we conclude that uptake of HePC is most probably mediatedvia a receptor-independent endocytotic mechanism.  相似文献   

16.
We studied constitutive and induced defensive traits (latex exudation, cardenolides, proteases, and C/N ratio) and resistance to monarch caterpillars (Danaus plexippus) in three closely related milkweed species (Asclepias angustifolia, A. barjoniifolia and A. fascicularis). All traits showed significant induction in at least one of the species. Jasmonate application only partially mimicked the effect of monarch feeding. We found some correspondence between latex and cardenolide content and reduced larval growth. Larvae fed cut leaves of A. angustifolia grew better than larvae fed intact plants. Addition of the cardenolide digitoxin to cut leaves reduced larval growth but ouabain (at the same concentration) had no effect. We, thus, confirm that latex and cardenolides are major defenses in milkweeds, effective against a specialist herbivore. Other traits such as proteases and C/N ratio additionally may be integrated in the defense scheme of those plants. Induction seems to play an important role in plants that have an intermediate level of defense, and we advocate incorporating induction as an additional axis of the plant defense syndrome hypothesis.  相似文献   

17.
三种黄皮属植物叶挥发油化学成分的研究   总被引:10,自引:0,他引:10  
利用水蒸气蒸馏法分别提取了3种黄皮属植物齿叶黄皮、黄皮和光滑黄皮叶的挥发油,经毛细管气相色谱-质谱联用仪 (GC-MS)分析,分别分离出38、81和28个峰,鉴定了其中的34、62和19种成分,所鉴定成分占挥发油总量的99.64%、92.85%和94.40%。挥发油的主要成分是单萜、倍半萜、酚类衍生物和脂肪族类化合物。  相似文献   

18.
This study investigates variation in the secondary chemistry of the bark of three closely related, winter-dormant species of white birch (Betula resinifera, B. pendula, and B. platyphylla) at different ontogenetic stages by using different plant parts (top and base). The experimental birches were grown for 4 years in two growing conditions (pot and field) at different nutrient levels. There was considerable species-specific quantitative and qualitative variation in the secondary chemicals in bark, but this was also affected by fertilization and the age of the plant. In general, there was greater chemical diversity in saplings than in seedlings. The study revealed three new components, secoisolariciresinol 9-O-β-glucopyranoside and two of its derivatives, that have not been reported previously for the bark of white birches. Principal component analysis showed that the species studied had a similar chemical composition at the juvenile stage, but as the plants grew, they became more clearly differentiated, which indicates that the species of older plants can be identified by chemotaxonomy. Evidently, the secondary chemistry of birches is under genetic control, but it is affected by properties of growing conditions and ontogeny. Electronic Supplementary Material Supplementary material to this paper is available in electronic form at  相似文献   

19.
A comparative chemical analysis of the larval nectar secretions and hemolymph from three unspecifically and facultatively ant-attended lycaenid species (Polyommatus coridon, P. icarus, and Zizeeria knysna) was performed by using high-performance liquid chromatography techniques. Sucrose was the main sugar component in all three species. In half of the samples of P. coridon, it was accompanied by glucose, whereas other sugars occurred only rarely. In P. icarus and Z. knysna, melezitose was the second-most important component, followed by fructose and glucose. Total sugar contents were 43.6 ± 14.8 g/l (mean ± SD) for P. coridon, 74.2 g/l for P. icarus, and 68.3 ± 22.6 g/l for Z. knysna. Up to 14 different identified amino acids were found in P. coridon nectar, with a total content of 9.7 ± 3.4 g/l. Leucine was always the major component (contributing 50% of overall amino acid content). Other important amino acids were tyrosine, proline, arginine, and phenylalanine. P. icarus nectar contained up to six amino acids with a total content of 1.2 g/l, dominated by tyrosine and phenylalanine. Z. knysna nectar contained alanine and proline, with only 0.3 ± 0.17 g/l total content. In the hemolymph of all species, up to 16 different amino acids occurred relatively regularly, with histidine dominating, followed by serine and proline. The amino acid pattern in hemolymph was considerably different from that of the nectar secretions. Larval diet weakly influenced P. coridon nectar sugars, and with a semisynthetic diet, a more homogeneous amino acid pattern was detected. Comparison with reports from other lycaenid species shows that secretions rich in amino acids are related to intimate, often obligate ant associations, whereas facultative, unspecific myrmecophiles rely on carbohydrates.  相似文献   

20.
Gustatory responsiveness of six adult squirrel monkeys, four spider monkeys, and five pigtail macaques to six bitter tastants was assessed in two-bottle preference tests of brief duration (2 min). Animals were given the choice between a 30-mM sucrose solution and defined concentrations of a bitter tastant dissolved in a 30-mM sucrose solution. With this procedure, Saimiri sciureus, Ateles geoffroyi, and Macaca nemestrina were found to significantly discriminate concentrations as low as 0.2, 0.05, and 0.1 mM quinine hydrochloride; 1, 1, and 0.05 mM caffeine; 20, 5, and 1 mM naringin; 5, 2, and 1 mM salicin; 0.01, 0.001, and 0.02 mM sucrose octaacetate; and 0.05, 0.01, and 0.5 mM denatonium benzoate, from the alternative stimulus. With the exception of naringin in the pigtail macaques, all three species rejected all suprathreshold concentrations of all bitter tastants tested. The spider monkeys and the pigtail macaques displayed the lowest taste avoidance thresholds with three of the six tastants each; in contrast, the squirrel monkeys displayed the highest taste avoidance thresholds with four of the six tastants. The across-tastant patterns of taste avoidance thresholds were identical in spider monkeys and squirrel monkeys; both species displayed the following order of sensitivity: sucrose octaacetate > denatonium benzoate > quinine hydrochloride > caffeine > salicin > naringin. All three primate species were more sensitive to the two artificial tastants (sucrose octaacetate and denatonium benzoate) compared to the four naturally occurring tastants. However, the concentrations detected by all three primate species with the four naturally occurring tastants are well below those reported in plants or arthropods consumed by these species suggesting that they may use bitterness as a criterion for food selection.  相似文献   

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