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排序方式: 共有1672条查询结果,搜索用时 0 毫秒
1.
2.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
3.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
4.
Philip W. Wirtz 《Alcoholism, clinical and experimental research》2007,31(S3):57s-63s
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
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
5.
表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
6.
R. Fock H. Bergmann H. Bußmann G. Fell E.-J. Finke U. Koch M. Niedrig M. Peters D. Scholz A. Wirtz 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2001,44(10):969-980
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
7.
The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献
8.
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
9.
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
10.
36例踝关节骨折合并下胫腓联合分离的治疗体会 总被引:1,自引:1,他引:0
0 引言 踝关节骨折是临床上较常见的关节内骨折,包含了腓骨骨折,内踝骨折,后踝骨折和下胫腓联合的损伤. 处理不当可导致踝穴的变形,下胫腓联合分离后期出现创伤性关节炎. 相似文献