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1.
Summary The results of comparative analyses of polynuclear aromatic hydrocarbons in marijuana and tobacco smoke indicate a considerably higher content of potential carcinogens in the former. A model experiment involving 9-tetrahydrocannabinol suggests that the pyrolysis products of cannabinoids are major contributors to the polynuclear aromatic hydrocarbons.We thank Dr.John Benner and Ms.Carolyn Keene of the University of Kentucky for help with the smoking experiments. This work was supported by Grant No. R01-DA-00507-01 from the National Institute of Mental Health.  相似文献   

2.
Summary Type II alveolar lung cells metabolize polycyclic aromatic hydrocarbons as indicated by measurements of aryl hydrocarbon hydroxylase activity and binding of tritium labeled benzo(a)pyrene to nuclear and cytoplasmic components.  相似文献   

3.
Xenon difluoride reacts with benzo[a]pyrene(BaP) in dichloromethane solution in an open system to give 6-fluorobenzo[a]pyrene. This method constitutes a direct route to fluorine substituted carcinogenic polycyclic aromatic hydrocarbons.  相似文献   

4.
Summary A blown bitumen Mexphalte R 90/40 with a high content of saturated hydrocarbons was degraded by several microorganisms to the same extent. In batch cultures ofSaccharomycopsis lipolytica, maximal biodegradation was estimated to be about 9% w/w, 3.2·10–3 g/cm2 and 3.1·10–3 cm of degraded bitumen. The Mexphalte R 90/40 degradation rate was closely coupled to biofilm formation. The microbial activity concerned predominantly the oxidation of saturated hydrocarbons. A direct distillation bitumen 80/100 with a low content of saturated hydrocarbons and a high content of aromatic hydrocarbons and resins was more resistant to biodegradation.  相似文献   

5.
Summary Xenon difluoride reacts with benzo[a]pyrene (BaP) in dichloromethane solution in an open system to give 6-fluorobenzo[a]pyrene. This method constitutes a direct route to fluorine substituted carcinogenic polycyclic aromatic hydrocarbons.Acknowledgment. This work was financed in part by a grant from The Israel Commission for Basic Research.  相似文献   

6.
    
Summary Aromatic mercaptals, thiolesters and sulfides are not stable when heated in indifferent solvents in the presence of Raney nickel, freed from hydrogen, depending on the course of the reaction from the previous treatment of the nickel and on the constitution of the compounds. We observed the formation of aromatic sulfides and binuclear hydrocarbons in yields which in some cases promise interesting preparative possibilities.  相似文献   

7.
A microfluorometric system allowing the mesurements of fluorescence decay (i.e. fluorescence lifetime) has been built. It will complete the microspectrofluorometric studies of absorbed compounds-polycyclic aromatic hydrocarbons, metabolites of benzo (a) pyrene-by single living cells and allows a better understanding of the intake and metabolisation of these compounds. The preliminary results with benzo (a) pyrene, dibenzocarbazole, pyrene are shown.  相似文献   

8.
Dimeric dihydrodiol dehydrogenase (DD) catalyzes the NADP(+)-dependent oxidation of trans-dihydrodiols of aromatic hydrocarbons to their corresponding catechols. The tertiary structure of dimeric DD consists of a classical dinucleotide binding domain comprising two betaalphabetaalphabeta motifs at the N-terminus, and an eight-stranded, predominantly anti-parallel beta-sheet, forming the C-terminal domain The aim of this review is to summarize the biochemical and structural properties of dimeric DD, compare it to enzymes that are structurally similar, and provide an insight into its catalytic mechanism and membership amongst a unique family of monomeric/oligomeric proteins that most likely share a common ancestry.  相似文献   

9.
Summary The authors describe the results of a quantum mechanical treatment of aromatic hydrocarbons enabling the determination of the electronic charge at each point of the molecule. They give the interpretation of the chemical reactivity of these substances by means of molecular diagramms.  相似文献   

10.
重金属和多环芳烃是土壤环境中的重要污染物,其复合污染土壤的修复已成为环境科学研究的热点问题。植物修复技术是目前修复土壤复合污染重要方法之一,但植物本身修复能力有限,需借助化学、微生物、基因工程等手段对其修复效果进行强化。本文对国内外近几年来植物修复重金属-多环芳烃复合污染强化措施研究成果进行综述,并重点讨论了植物根际生长促进菌及菌根在强化修复中的应用,在此基础上对未来该领域需要深入研究的科学问题进行了阐述。  相似文献   

11.
Summary The proteolytic activity of polynuclear leucocytes of the guinea-pig was determined prior to and after incubation with the pseudorabies virus (the virus of Aujeszky disease). It was found that the proteolytic activity of leucocytes treated with the virus was increased by 34.5%. There is a brief discussion of the biological value of the increased proteolytic activity.  相似文献   

12.
多环芳烃的毒理学特征与生物标记物研究   总被引:4,自引:0,他引:4  
多环芳烃主要来自于碳氢化合物不充分燃烧,在大气、水体和土壤中广泛地存在,由于多环芳烃具有疏水性、致癌性、致畸性、致突变性和生物难降解性,因此多环芳烃被看作是持久性有机污染物的主要代表。目前,多环芳烃的毒理学研究是环境科学领域的热点问题之一,研究主要集中在多环芳烃及其在环境中的降解和转化产物在体内的吸收、分布、排泄和代谢转化,以及阐明多环芳烃对人体毒作用的发生、发展和消除的各种条件和机理。生物标记物是有机污染物风险评价的核心内容,可以探索多环芳烃对人体健康损害的早期观察指标,即用最灵敏的探测手段,找出环境污染物作用于机体后最初出现的生物学变化,以便及早发现并设法排除。本文阐述了环境中多环芳烃的来源、性质和分布,评述了多环芳烃的毒理学研究进展,并对今后多环芳烃的毒理学的发展方向进行了论述。  相似文献   

13.
Zusammenfassung Die Literatur über die verschiedenen Bestandteile des Tabakrauchs ist kritisch gesichtet worden, und the kanzerogene Eigenschaft einzelner Verbindungen wurde angeführt.

This work was supported by a grant from the Damon Runyon Memorial Fund for Cancer Research.  相似文献   

14.
Zusammenfassung Die Hemmung der Alkoholdehydrogenase aus Hefe durch Zigarettenrauch beruht auf verschiedenen Inaktivierungsmechanismen. Die Gasphase zeigt eine kompetitive Hemmung, die Partikelphase und der ganze Rauch eine gemischte Hemmung. Da die Hemmung durch den ganzen Rauch nicht der Summe der Hemmungen beider Phasen entspricht, ist anzunehmen, dass Wechselwirkungen zwischen den Inhibitoren und Antagonisten vorliegen.  相似文献   

15.
Summary Hashish smoke has been proved to be active in the Sidman avoidance. Its activity is similar to that of hallucinogens.  相似文献   

16.
17.
Hashish smoke has been proved to be active in the Sidman avoidance. Its activity is similar to that of hallucinogens.  相似文献   

18.
Summary Chemical components of tarsal glands ofBombus terrestris workers were identified by combined gas chromatographic/mass-spectrometric analysis. The 17 components are exclusively saturated and unsaturated hydrocarbons.  相似文献   

19.
Summary Ca2+-dependent ATPase ofAspergillus nidulans was found to be stimulated by aminoacids in vitro. Both histidine and arginine stimulated the enzyme more effectively than the aromatic aminoacids. Supplementation of the growth medium with basic or aromatic aminoacids increased the enzyme activity in vivo 2–6-fold. The enhanced activity observed in these cultures in vivo was not mediated through the synthesis of new isoenzyme, as observed in proteinenriched cultures, but appeared to be through the activation of enzyme activity.  相似文献   

20.
Zusammenfassung Mit einer Analysenmethode gelingt es, Marijuanarauch von einer Zigarette oder weniger durch Kombination von Anreicherungsverfahren mit hochauflösender Gaschromatographie in Zimmerluft nachzuweisen. Charakteristische Profile von 200 bis 300 Komponenten (darunter Cannabinoide), die sich deutlich von denen von Tabakrauch unterscheiden, wurden mit Hilfe von Glaskapillarsäulen gewonnen.  相似文献   

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