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1.
This study focuses on the perception of large scale application of nuclear energy and coal in the Netherlands and France. The application of these energy-sources and the risks and benefits are judged differently by various group in society. In Europe, France has the highest density of nuclear power plants and the Netherlands has one of the lowest. In both countries scientists and social scientists completed a questionnaire assessing the perception of the large scale application of both energy sources. Furthermore, a number of variables relating to the socio cultural and political circumstances were measured. The results indicate that the French had a higher risk perception and a more negative attitude toward nuclear power than the Dutch. But they also assess the benefits of the use of nuclear power to be higher. Explanations for these differences are discussed.  相似文献   
2.
Adenine N1-oxide is a DNA lesion whose formation involves the specific oxidation of the adenine base by hydrogen peroxide under nonradical conditions. The damage may be measured using a HPLC/32P-postlabeling method, which however cannot be used for routine analysis. We propose herein as an alternative an immunological assay which allows a rapid evaluation of the level of adenine N1-oxide in DNA exposed to oxidative stress. Two polyclonal antibodies were raised using two different strategies for the coupling of the hapten to the protein. The first approach is based on the universal method of Erlanger and Beiser, whereas the preparation of the second antigen involves the conjugation of a morpholino derivative of adenosine N1-oxide to the carrier protein. The affinity and the specificity of those antibodies were determined by competitive enzyme-linked immunosorbent assay. The antibody obtained by the traditional method shows some cross-reactivity with normal nucleotides, whereas for the other antiserum, the selectivity was found to be higher. Therefore, this polyclonal antibody was used to quantify the level of adenine N1-oxide in calf thymus DNA oxidized either by m-chloroperbenzoic acid or by hydrogen peroxide. The detection limit of the assay is four residues of adenine N1-oxide per 10(6) normal bases. The level of adenine N1-oxide in nonmodified DNA was lower than the detection limit of the assay, whereas in mCPB- and H2O2-modified DNA, it could be up to 14 and 0.7 adenine N1-oxide residues per 10(4) normal bases, respectively.  相似文献   
3.
Delta opioid peptide [D-Ala2,D-leu5]enkephalin (DADLE) can prolong organ preservation and increases myocardial tolerance to ischemia. Our study examined the protective property of DADLE against methamphetamine- (METH) induced dopaminergic terminal damage in the central nervous system. Because the neurotoxicity of METH involves reactive oxygen species, we also examined if DADLE might be an antioxidative agent in vitro. DADLE at 2 and 4 mg/kg (i.p.), given 30 min before each METH administration (5 or 10 mg/kg, i.p., four injections in a day at 2-hr intervals), dose-dependently blocked the METH-induced long-term dopamine transporter loss. The opioid antagonist naltrexone blocked this action of DADLE in both aspects of striata but tends not to affect the effects of DADLE in the nucleus accumbens. DADLE did not alter changes in body temperature induced by METH. The reduction of striatal dopaminergic content and tyrosine hydroxylase activity caused by METH, however, were not blocked by DADLE. In vitro, DADLE was approximately equipotent to glutathione in inhibiting both superoxide anion formation induced by xanthine oxidase and hydroxyl radical formation evoked by ferrous/citrate complex. DADLE was only slightly less potent than glutathione in inhibiting the iron/ascorbate-induced brain lipid peroxidation. These results suggest that DADLE can protect the terminal membranes of dopaminergic neurons against METH-induced insult but not the loss of dopaminergic content and tyrosine hydroxylase activity and that this action of DADLE might involve opioid receptors as well as the sequestration of free radical.  相似文献   
4.
A new type of vicinal base lesion was isolated from the photosensitization of TpdG in aerated aqueous solution. One- and two-dimensional NMR measurements were used together with mass spectrometry to accurately characterize the new adduct. Chemical detection of guanidine provided additional structural information on the base moiety at the 3'-OH terminal end. Altogether the experiments results were indicative of the occurrence of a covalent bonding between the pyrimidine ring on the 5'-OH terminal end and the imidazole ring on the 3'-OH terminal end through a methylene bridge. Photosensitization studies of TpdG, thymidine, and 2'-deoxyguanosine in the presence of either benzophenone, menadione, or riboflavin associated with isotopic labeling experiments using enriched oxygen and water provided relevant information on the mechanism of formation of the adduct. The results of these experiments clearly demonstrated that the initial event leading to the formation of the lesion is the abstraction of a hydrogen atom from the methyl group of the thymine base moiety of TpdG. This is followed by the addition of the methyl-centered radical to the C-4 atom of the guanine ring which gives rise to the vicinal lesion after reaction with molecular oxygen and subsequent rearrangement.  相似文献   
5.
6.
Collagen-induced arthritis (CIA) is an animal model of rheumatoid arthritis (RA) that can be regressed with Taxol (paclitaxel), a chemotherapeutic agent. To identify structural changes that occur with involution, the synovium from naive, untreated CIA, and Taxol-treated CIA rats were evaluated by light microscopy plus transmission and scanning electron microscopy. Analysis included detailed images of vascular networks using polymeric corrosion casts. The CIA synovium was morphologically similar to human RA synovium. In CIA, the integrity of the intimal lining is lost by Type-B synoviocytes becoming highly elongated and polarized toward the joint space, resulting in non-overlapping cellular processes and the elimination of the basal lamina. In addition, the lining expanded from a width of 6-10 microns in naives to 200-250 microns in CIA due primarily to increased numbers of both Type-A and -B synoviocytes and more interstitial matrix. Vascular corrosion casts of CIA synovium illustrated a marked increase in blood vessel volume and an extensive interconnecting vascular architecture; neovascular arrays were observed to project toward the synovial surface. In Taxol-treated CIA, the synoviocyte and neovascular components reverted to the naive synovium morphology, suggesting that this agent might be useful in the therapy of RA.  相似文献   
7.
Studied the influence of various cognitive modalities on risk assessment. Human Ss: 78 normal male and female French adults (university students). Ss were presented with information related to a potential environmental danger and asked to evaluate the degree of risk. The information involved 3 categories of data presented under 3 experimental conditions: representativeness, availability, and anchoring of the relevant information. A control condition offering no information on which to base the risk assessment was also included. Subjective evaluations of the degree of risk served as the dependent variable. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
This paper reports a factor analysis of the symptoms of nicotine dependence that were determined in an assessment of 821 current cigarette-smoking research volunteers, according to the Diagnostic and Statistical Manual of Mental Disorders, 3rd edition, revised (DSM-III-R) of the American Psychiatric Association as well as an analysis of a subset who unsuccessfully attempted to quit (n=636). In the total sample, two factors with eigenvalues greater than 1 accounted for 62.7% of the variance. When the factor analysis was repeated with the subset of research volunteers who unsuccessfully attempted to quit, only one DSM-III-R nicotine dependence symptom loaded on the second factor. This finding suggests that the two-factor structure found in this and a previous factor analysis study of the nicotine dependence segment of the DSM-III-R may be an artifact of the skipout pattern of the DSM-III-R, which assumes that smokers who have not attempted to quit have not experienced withdrawal symptoms or used tobacco to avoid these symptoms. Goodness-of-fit measures suggested that the two-factor structure is a better fit than the one-factor structure for both the total population and the subset who unsuccessfully attempted to quit or cut down. Our sample of current smokers who had not attempted to quit (n=185) was too small to permit factor analyses. Further work with other large samples from the general population of current smokers who have unsuccessfully attempted to quit as well as those who have not attempted to quit will enhance our understanding of the factor structure of the nicotine dependence segment of the DSM-III-R and clarify the effect of the skipout pattern on its factor structure.  相似文献   
9.
The drug 3 beta-[4'-iodophenyl]tropan-2 beta-carboxylic acid methyl ester (RTI-55) is a cocaine congener with high affinity for the dopamine transporter (Kd < 1 nM). The present study characterized [125I]RTI-55 binding to membranes prepared from rat, monkey and human caudates and COS cells transiently expressing the cloned rat dopamine (DA) transporter. Using the method of binding surface analysis, two binding sites were resolved in rat caudate: a high-capacity binding site (site 1, Bmax = 11,900 fmol/mg of protein) and a low-capacity site (site 2, Bmax = 846 fmol/mg of protein). The Kd (or Ki) values of selected drugs at the two sites were as follows: (Ki for high-capacity site and Ki for low-capacity site, respectively): RTI-55 (0.76 and 0.21 nM), 1-[2-diphenyl-methoxy)ethyl]-4-(3-phenylpropyl)piperazine (0.79 and 358 nM), mazindol (37.6 and 631 nM), 2 beta-carbomethoxy-3 beta-(4-fluorophenyl)tropane (45.0 and 540 nM) and cocaine (341 and 129 nM). Nisoxetine, a selective noradrenergic uptake blocker, had low affinity for both sites. Serotonergic uptake blockers had a high degree of selectivity and high affinity for the low-capacity binding site (Ki of citalopram = 0.38 nM; Ki of paroxetine = 0.033 nM). The i.c.v. administration of 5,7-dihydroxytryptamine to rats pretreated with nomifensine (to protect dopaminergic and noradrenergic nerve terminals) selectively decreased the Bmax of site 2, strongly supporting the idea that site 2 is a binding site on the serotonin (5-HT) transporter. This serotonergic lesion also increased the affinity of [125I]RTI-55 for the DA transporter by 10-fold. The ligand selectivity of the caudate 5-HT transporter was different from the [I125]RTI-55 binding site on the 5-HT transporter present in membranes prepared from whole rat brain minus caudate. The [125I]RTI-55 binding to the DA transporter was further resolved into two components, termed sites 1a and 1b, by using human and monkey (Macaca mulatta) caudate membranes but not the membranes prepared from rat caudate or COS cells that transiently expressed the cloned cocaine-sensitive DA transporter complementary DNA. Similar experiments also resolved two components of the caudate 5-HT transporter. Viewed collectively, these data provide evidence that [125I]RTI-55 labels multiple binding sites associated with the DA and 5-HT transporters.  相似文献   
10.
We establish a Biological Oxygen Demand, BOD, model in a pure culture during growing phases. This model, exprimed in reduced coordinates, is used to do a methodologic study of the BOD measure on urban and industrial effluents and on river waters. The different types of curves observed are described using dimensionless numbers. We study the influence of the method used and of the initial concentration in present or introduce micro-organisms on the numerical value of result obtained for a limited period (5 days).

We show that this model corresponds for weak values of the dimensionless number n, to the FAIR's model of first pseudo order. The dimensionless number n represent the ratio between the initial substrate concentration and the substrate equivalent of the biomass initially present.  相似文献   

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