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Volume and profile of alcohol consumption among students and classmates as predictors of aggression and victimization: a multilevel analysis among Swiss adolescents

Objective:  

To test the effects of the volume of alcohol consumption and drinking patterns on alcohol-related aggression and victimization, both at the individual and class levels.  相似文献   
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A series of 5-hydroxy and 5-benzyloxy analogs of the antiarrhythmic and multidrug resistance (MDR) modulating drug propafenone was synthesized and the MDR-modulating activity of the compounds was evaluated using a daunomycin efflux assay system. The key step of the synthesis is the selective reduction of the double bond in 1 without cleavage of the benzyl group thus leading to the phenol 3 . Alkylation with epichlorohydrine followed by nucleophilic epoxide ring opening gave the benzylated target compounds 5a–d . Subsequent cleavage of the benzyl group gave the 5-hydroxy analogs 6a–d . Structure activity relationship studies showed, that the 5-hydroxy derivates 6a–d fit the log P/log potency correlation line previously established for a series of propafenone analogs. In contrast, all four 5-benzyloxy analogs 5a–d showed almost identical EC50 values, independent of their log P value.  相似文献   
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Amplification of the graft-versus-host reaction by partial body irradiation   总被引:1,自引:0,他引:1  
An experimental model has been developed for the study of combined effects of partial body irradiation (PBI) and graft-versus-host disease (GVHD) in which irradiation is delivered to the thorax 24 hr prior to induction of GVHD in hybrid mice by the injection of parental lymphoid cells. In mice irradiated to 1000 cGy or exposed to low doses of allogeneic lymphoid cells (20 X 10(6)), survival was 100% at 250 days. In contrast, combination of the two treatments, GVHD and PBI, resulted in a mortality of 83% and a mean survival time of 29 days, indicating synergy between GVHD and PBI. From histological studies of the lung it appeared that about 40% of the deaths occurring after combined GVHD/PBR treatment might be attributable to pneumonia. The cause of death in the remaining mice receiving combined treatment is not known. Mice receiving combined PBI/lymphoid cell treatment develop a characteristic skin lesion that is not seen in nonirradiated mice and is confined to the irradiated area. The effect of preinduction PBR on the timing and severity of GVHD is similar to that which would be produced by an increase in the number of effector cells.  相似文献   
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Development of the central nervous system (CNS) involves the transformation of a two-dimensional epithelial sheet of uniform ectodermal cells, the neuroectoderm, into a highly complex three-dimensional structure consisting of a huge variety of different neural cell types. Characteristic numbers of each cell type become arranged in reproducible spatial patterns, which is a prerequisite for the establishment of specific functional contacts. The fruitfly Drosophila is a suitable model to approach the mechanisms controlling the generation of cell diversity and pattern in the developing CNS, as it allows linking of gene function to individually identifiable cells. This review addresses aspects of the formation and specification of neural stem cells (neuroblasts) in Drosophila in the light of recent studies on their segmental diversification.  相似文献   
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In a single outbreak on the East coast of Madagascar, more than 500 people, 98 of whom died, were poisoned by the flesh of a shark, Carcharhinus amboinensis. From clinical symptoms it can be concluded that this poisoning is due to ciguatera toxins. It is the first case of a severe outbreak caused by a shark, and it is the first case with a mortality rate of 20%.  相似文献   
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Expression of leptin receptor (OB-R) mRNA was detected in the human anterior pituitary as well as in ACTH-secreting and nonsecreting pituitary adenomas by RT-PCR with primers recognizing all receptor splice variants. Primers specific to the long splice variant of the leptin receptor (OB-Rb), containing the putative intracellular signalling domain, also revealed a strong expression in normal and adenomatous anterior pituitaries. These results indicate that the pituitary is a possible target tissue of leptin action and might be involved in leptin regulation of pituitary hormone secretion.  相似文献   
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Basic materials for contact lenses were obtained by radical copolymerization of linear α,ω-bis(methacryloyloxy)-terminated oligo- and poly(dimethylsiloxane)s, methyl methacrylate and 2,2,3,3,4,4,4-heptafuorobutyl methacrylate. Oxygen permeabilities, contact angles and ball indentation hardness were determined.  相似文献   
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