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131.
The syndrome of anabolic-androgenic steroid (AAS) dependence, though well recognized, remains poorly studied. In this preliminary psychometric study, American and British investigators separately administered a structured diagnostic interview module, based on recently proposed criteria for AAS dependence, to 42 male AAS users in Middlesbrough, England. Another investigator, blinded to the diagnostic interview findings, assessed self-reported symptoms of “muscle-dysmorphia”; effects of AAS on various aspects of functioning; and maximum proportion of annual income spent on AAS. We also assessed demographic measures, history of other substance use, and performance on a hypothetical AAS-purchasing task. The interview module yielded very good interrater reliability (kappa = 0.76 and overall intraclass correlation = 0.79) and strong internal consistency (Cronbach's alpha = 0.77–0.87). Men diagnosed as AAS-dependent, when compared to nondependent men, reported significantly earlier onset of AAS use, longer duration and higher maximum doses of AAS used, more frequent use of other performance-enhancing drugs, and a somewhat larger maximum percentage of income spent on AAS. Dependent users also “bought” more AAS in the hypothetical purchase task, but rated significantly more negatively the effects of AAS on their mental health—findings all suggesting that the diagnosis of AAS dependence shows construct validity. As a group, AAS users showed high preoccupation with muscular appearance, but dependence per se was not significantly associated with this measure—suggesting that the diagnosis of AAS dependence shows some evidence of discriminant validity. Collectively, these findings suggest that AAS dependence may be diagnosed reliably, with preliminary evidence for construct and discriminant validity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
132.
Adjusted Traffic Load for Bridges under Communal Responsibility Recently the traffic loads of bridges of the EC1 have been introduced in Germany under the responsibility of the Federal Ministry of Transport, Building and Urban Affairs. Usually the Load Model LM1 has to be used for all new bridge structures with the adjusted values of αQ1 = 0, 8, αQ2 = 0, 8, αQ3 = 0. A further classification has not been defined. This makes sense for the highway bridges and federal road bridges, because usually they have longer spans where a further reduction of the α‐values is not justified. In the sphere of influence of cities and villages the situation is totally different, because many bridges are short and are buildt as single span girder bridges or single frame bridges. In case of those bridges the LM1 leads to conservative results because the geometry and the total weight and the axle weight of the real lorries are limited and cannot develop those high inner forces and moments. The authors developed a proposal for further reduction of the α‐values dependent on the geometry and the statical system of the bridge without leaving the safety level of the Eurocode. Also for strengthening existing bridges these values can be used. The development has been undertaken in colaboration with the civil engineering offices in Frankfurth/Main, Leipzig and Stuttgart.  相似文献   
133.
Filarial nematode parasites establish long-term chronic infections in the context of an antiparasite immunity that is strongly biased toward a Th2 response. The mechanisms that lead to this Th2 bias toward filarial antigens are not clear, but one possibility is that the parasites produce molecules that have the capacity to proactively modify their immunological environment. Here we report that filarial parasites of humans secrete a homologue of the human proinflammatory cytokine macrophage migration inhibitory factor (MIF) that has the capability of modifying the activity of human monocytes/macrophages. A cDNA clone isolated from a Brugia malayi infective-stage larva expression library encoded a 12.5-kDa protein product (Bm-MIF) with 42% identity to human and murine MIF. MIF homologues were also found to be expressed in the related filarial species Wuchereria bancrofti and Onchocerca volvulus. Bm-mif was transcribed by adult and larval parasites, and the protein product was found in somatic extracts and in the parasite's excretory-secretory products. Immunohistocytochemistry revealed that Bm-MIF was localized to cells of the hypodermis/lateral chord, the uterine wall, and larvae developing in utero. Unexpectedly, the activities of recombinant Bm-MIF and human MIF on human monocytes/macrophages were found to be similar. When placed with monocytes/macrophages in a cell migration assay, Bm-MIF inhibited random migration. When placed away from cells, Bm-MIF induced an increase in monocyte/macrophage migration that was specifically inhibited by neutralizing anti-Bm-MIF antibodies. Bm-MIF is the first demonstration that helminth parasites produce cytokine homologues that have the potential to modify host immune responses to promote parasite survival.  相似文献   
134.
This report presents two cases of totally occluded internal carotid arteries, verified by angiography. In both cases the vessel was recanalised under heparinisation. This was first detected by duplex carotid sonography. Angiographic follow-up showed a high-grade stenosis at the origin of the internal carotid artery. Both female patients were then operated successfully. It is important to consider the possibility of spontaneous recanalisation of an occluded internal carotid artery because there are clear indications for operative treatment in such a case. In case of total occlusion, as a rule no operative treatment is possible.  相似文献   
135.
Project management in a multicompany, multinational, multidiscipline environment with relatively small resources is considered. The impact of that environment and the methods to cope with it are examined, the experiences of a selected number of methods being reported. An attempt is made at providing a pathway for the synthesis of creativity and engineering leading to a minimal time span for completion of a project. The cost of slippage is discussed; along with a company's lost opportunities, slippages are considered to be the most detrimental project failures.  相似文献   
136.
In the present study, a methodology based on strength hierarchy has been proposed for upgradation of original gravity load designed (GLD) reinforced concrete (RC) structures. Exterior beam–column joint of an RC structure has been considered as the target sub-assemblage and the target strength of the deficient sub-assemblage was decided from that of a seismically designed ‘Ductile’ one. Three different types of upgradation schemes were investigated where shear- and flexural-strengthening were provided by Fiber Reinforced Plastics (FRP) and weak joint region of ‘GLD’ sub-assemblage was upgraded by steel plate jacketing. The original (‘GLD’-, ‘NonDuctile’-, ‘Ductile’-) and upgraded-sub-assemblages were investigated under repeated reverse cyclic loading. It was observed that the ‘GLD’ specimen seized to function under reverse loading and subsequent improvements, though not optimal, were observed from ‘NonDuctile’ and ‘Ductile’ specimens. It was further found out that the upgraded specimens showed considerable improvement in strength deterioration, stiffness degradation and energy dissipation. Further, the upgraded specimens with adequate energy dissipation could even be able to shift the plastic hinge from the joint face into the beam which was not observed even in original ‘Ductile’ specimen. The upgraded schemes are simple, practically feasible and efficient as well.  相似文献   
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