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A note of encouragement to those hesitant or waiting to write for our journal, together with a guide to some of the ‘props’ of the trade. 相似文献
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Max Knaapen Anna H. Koch Charlotte Koch Karel T. Koch Xiaofei Li Peter C. van Rooij Jan G.P. Tijssen Ron J. Peters Allard C. van der Wal Peter Damman Robbert J. de Winter 《Cardiovascular pathology》2013,22(1):49-53
BackgroundIn patients presenting with an acute coronary syndrome, left over right coronary dominance appears to be independently associated with increased long-term mortality. This could lead to decreasing numbers of patients with a left dominant coronary artery system in older age groups.MethodsWe assessed the type of coronary dominance in different age groups in postmortem angiograms that were routinely performed at autopsy between 1993 and 2007. Coronary dominance was determined by identifying the origin of the posterior descending artery and posterolateral branches on postmortem angiography. Age, gender, and cause of death were recorded from the autopsy database. The prevalence of left dominant, right dominant, and codominant systems was determined in three increasing age categories, with cutoffs based on tertiles.ResultsA total 1620 coronary angiograms were assessed; 167 were excluded because it was not possible to determine coronary dominance. The median age of all patients was 71 years; 56% were male. Of all deaths, 40% were classified as cardiac. Regarding coronary dominance, 81.2% was right, 9.1% was left, and 9.7% was codominant. Overall, a decrease in prevalence of left and codominant coronary systems was observed with increasing age in the three age cohorts (≤63years, 64–75 years, and ≥76 years) (P=.001 for overall comparison).ConclusionsIn this large autopsy cohort, the prevalence of a left dominant or codominant coronary system decreased with increasing age. These findings could relate to a slightly higher risk of mortality in case of left versus right coronary artery occlusion. 相似文献
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Netta Lev-Tov Chattah Kornelius Kupczik Ron Shahar Jean-Jacques Hublin Steve Weiner 《Journal of anatomy》2011,218(1):87-95
Teeth adopt a variety of different morphologies, each of which is presumably optimized for performing specific functions during feeding. It is generally agreed that the enamel cap is a crucial element in controlling the mechanical behavior of mammalian teeth under load. Incisors are particularly interesting in terms of structure–function relations, as their role in feeding is that of the ‘first bite’. However, little is known how incisor cap morphology is related to tooth deformation. In the present paper we examine the mechanical behavior of mandibular central incisors in the cercopithecine primate Macaca mulatta under loads similar to those encountered during ingestion. We map three‐dimensional displacements on the labial surface of the crown as it is compressed, using electronic speckle pattern interferometry (ESPI), an optical metrology method. In addition, micro‐computed tomography is used to obtain data regarding the morphology of the enamel cap, which in the M. mulatta lower incisors exhibits missing or very little enamel on the lingual face. The results showed that although compressed along a longitudinal axis, deformation in the incisors mostly occurred in the lingual direction and orthogonal to the direction of the applied load. Both isolated, embedded teeth and teeth in the mandible showed considerable lingual deformation. Incisor deformation in the mandible was generally greater, reflecting the additional freedom of movement enabled by the supporting structures. We show that the association with adjacent teeth in the arch is significant for the behavior of the tooth under load. Finally, loading two teeth simultaneously in the mandible showed that they work as one functional unit. We suggest that these results demonstrate the importance of enamel cap morphology in directing deformation behavior; an ability stemming from the stiffness of the enamel cap overlying the more pliable dentin. 相似文献
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Educational tracking based on academic ability accounts for different school dynamics between vocational versus academically‐oriented high schools in Taiwan. Many educational practitioners predict that the settings of vocational schools and academic schools mediate school violence in different ways. Alternatively, some researchers argue the actual mediating mechanism may not vary significantly between the different school types in different cultures. The purpose of this study was to examine how within‐school variables (school engagement, risky peers, and student–teacher interaction) mediate external‐school variables (personal traits, parental monitoring, and victimization) and school violence in Taiwanese vocational and academically‐oriented schools. Structural equation modeling analysis, based on a national representative sample (N=7,841), suggested school violence was mediated through school variables. Similar mediational findings were found between academic and vocational schools as well as between males and females. Findings suggest that school violence is mediated by within‐school variables in similar ways across different school types, genders, and cultures. © 2010 Wiley Periodicals, Inc. 相似文献
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Trevor A. Hart David Moskowitz Christopher Cox Xiuhong Li David G. Ostrow Ron D. Stall Pamina M. Gorbach Michael Plankey 《The journal of sexual medicine》2012,9(4):1106-1113
IntroductionErectile dysfunction (ED) is highly prevalent among human immunodeficiency virus‐seropositive (HIV+) men who have sex with men (MSM). There is a need for additional research to determine the correlates of HIV+ and HIV‐seronegative (HIV?) MSM, especially regarding nonantiretroviral medication use.AimsThis study examined the prevalence of ED and the sociodemographic, medical conditions, medication use, and substance use correlates of ED among HIV+ and HIV? MSM.MethodsA modified version of the International Index of Erectile Function (IIEF) for MSM was self‐administered by participants enrolled in the Multicenter AIDS Cohort Study, an ongoing prospective study of the natural and treated histories of HIV infection among MSM in the United States. The study sample included 1,340 participants, including 612 HIV+ and 728 HIV? men. Poisson regression with robust error variance was used to estimate prevalence ratios of ED in multivariable models in combined (HIV+/?) and separate analyses.Main Outcome MeasureED was determined by the summed scores of a modified version of the IIEF validated among MSM.ResultsTwenty‐one percent of HIV+ MSM and 16% of HIV? MSM reported ED. Being >55 years of age, black race, cumulative pack years of smoking, cumulative antihypertensive use, and cumulative antidepressant use had significant positive associations with the prevalence of ED in the total sample. Among HIV+ men, duration of antihypertensive use and antidepressant use were significantly associated with increasing prevalence of ED. Among HIV? men, being >55 years of age, black race, and cigarette smoking duration were associated with increased prevalence of ED.ConclusionPredictors of ED may differ by HIV status. Although smoking cessation and effective medication management may be important as possible treatment strategies for ED among all MSM, there may be a burden on sexual functioning produced by non‐HIV medications for HIV+ men. Hart TA, Moskowitz D, Cox C, Li X, Ostrow DG, Stall RD, Gorbach PM, and Plankey M. The cumulative effects of medication use, drug use, and smoking on erectile dysfunction among men who have sex with men. J Sex Med 12;9:1106–1113. 相似文献
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