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Background:  While causal modeling is generally well known to alcohol researchers, several causal structures (including suppression, mediated moderation, and moderated mediation) are often poorly understood and seldom employed when investigators seek to model the complex mechanisms of behavior change, despite their widespread applicability to the field.
Methods:  This paper compares and contrasts five basic structures of causal modeling in the context of contemporary alcohol research and demonstrates how mechanisms of behavior change can be conceptualized and tested as parallel and serial sequences of these basic causal structures, forming causal chains.
Conclusion:  Recent methodological developments, while representing an important advancement for the field, fail to adequately address the complexities of alcohol dependence phenomena. A differentiation between frequently combined forms of these causal structures is proposed that would better address the needs of the field.  相似文献   
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The purpose of this study is to show the spectrum of adjacent organ invasion and to make a brief review of hepatic alveolar hydatid disease (AHD), using CT and MR imaging. We retrospectively reviewed CT and MR images of three patients with various adjacent organ invasions surgically and histologically proven to be AHD. Local invasion to right kidney and adrenal, right hemidiaphragm and lung were detected in one patient, right adrenal in another patient and gall bladder, duodenum, gastric wall and pancreas invasion in the other. AHD may rarely extend to the gall bladder, stomach, duodenum, pancreas, right adrenal and kidney, diaphragm, pleura and lung. The extension of the disease outside the liver is usually encountered in patients with large, peripherally located masses in the advanced stage of the disease.  相似文献   
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The World Health Organization (WHO) and the majority of the influenza experts assume that an influenza pandemic might reemerge again at any time. Therefore WHO has called upon all member states to set up a national pandemic preparedness plan. For Germany such a plan is long overdue. In order to gain as much time as possible early identification of the pandemic virus is of highest priority. Furthermore progression of a pandemic is influenced by the time needed to develop a subtype specific vaccine as well as by the vaccines availability. However, in case of a pandemic a shortage of vaccines and prophylactic pharmaceuticals cannot be avoided. Therefore, decisions have to be made in order to establish priorities concerning the vaccination and the prophylactic and/or therapeutic antimicrobial treatment of selected sub-populations. There is also a need to lay down measures ensuring the distribution of vaccines and antiviral drugs, adequate health care and ambulance service, and the organization of dignified funerals of the deceased. It is also necessary to enter into an early agreement with vaccine manufacturers on a guaranteed supply of respective batches of vaccine doses. In addition procedures should be established to allow an increase in vaccine production in case of a pandemic. There is also a need for early agreements with the manufacturers of antiviral agents and for a decision concerning the establishment of a national stockpile to guarantee an adequate supply. Some measures must already be taken in the inter-pandemic period. Those are: enhancement of surveillance and research, development of new vaccines and new methods of vaccine production, licensing of new vaccines in case of a pandemic and establishment of a national influenza committee. Problems like the effectiveness of antiepidemic measures, such as immigration control and the closing of schools, must be solved in advance of a pandemic.  相似文献   
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Zusammenfassung Hintergrund: Bei Patienten mit stumpfem Thoraxtrauma muss mit einer Contusio cordis gerechnet werden. Das Spektrum der Symptomatik variiert von einer leichten regionalen myokardialen Funktionsstörung bis hin zur Ruptur und zum plötzlichen Herztod. Fallbeschreibung: Ein 27-jähriger Patient wurde nach einem Fußtritt gegen die Brust bei Kammerflimmern reanimiert. Das EKG sowie das Enzymmuster entsprachen denen eines akuten Myokardinfarkts, echokardiographisch zeigte sich eine Hypokinesie apikal und anteroseptal bei mittelgradig reduzierter Pumpfuktion. Die 10 Tage nach dem Trauma durchgeführte Koronarangiographie und Lävokardiographie ergaben einen unauffälligen Befund. Schlussfolgerung: Als Ursache des primären Kammerflimmerns und der initialen elektro- und echokardiographischen Befunde muss aufgrund der Anamnese eine Contusio cordis diskutiert und in der Therapie berücksichtigt werden. Abstract Background: Patients with a blunt chest trauma often sustain myocardial contusion. The spectrum of symptoms varies from regional myocardial dysfunction to myocardial rupture of sudden cardiac death. Case Report: After a kick against his chest, a 27-year-old patient was resuscitated because of ventricular fibrillation. ECG and enzymatic pattern corresponded to an acute myocardial infarction, the echocardiogram revealed an apical and anteroseptal hypokinesia. 10 days after the acute event, coronary arteriography and ventriculography did not show any abnormalities. Conclusion: On the basis of the anamnesis, a myocardial contusion must be discussed as reason for the ventricular fibrillation and the pathologic findings in ECG and echocardiogram. This has to be considered in the therapy.  相似文献   
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Deprivation of form vision by the fitting of translucent occluders suppressed the diurnal cycling of enkephalinergic amacrine cells (the ENSLI amacrine cells), in the chicken. Daily periods of normal vision or enforcing temporal contrast using strobe lighting appeared to restore normal functioning of the ENSLI cells. These results suggest that the ENSLI cells are involved in retinal circuits that assess the quality of the visual image and control eye growth.  相似文献   
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The prevalence of obesity in Germany has risen steadily in the last years; about 50% of the German population are overweight. There are various methods for determining obesity, such as BMI, the pattern of fat distribution, and the waist to hip ratio. Overweight is associated with chronic illnesses such as arterial hypertension, pulmoarterial hypertension, cardiomyopathy with left and right heart insufficiency, diabetes mellits type 2, all of which lead to an increased risk of morbidity and mortality. In addition, psychiatric comorbidity is known to occur. The care of obese patients provides an increasing medical and technical challenge in emergency medicine. We discuss the particular difficulties of examining obese patients in the emergency room (problems examining certain areas and in diagnosis due to excessive fatty tissue), at monitoring, in determining venous or intraosseous entrances, in airway management, respiration and artificial respiration, and during rescue and transport, and solutions offered. The outcome is, as a matter of course, worse in obese patients than in those with normal weight.  相似文献   
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