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41.
Unique variant of partial anomalous pulmonary venous connection with intact atrial septum 总被引:1,自引:0,他引:1
Summary Partial anomalous pulmonary venous connections (PAPVCs) are rare in association with an intact atrial septum. However, the diagnosis should be considered in patients with otherwise unexplained findings of left-to-right shunt and right heart enlargement. An unusual variant is presented, which we considered unsuitable for operative repair, based on findings at catheterization. Developmental, hemodynamic, and surgical considerations are discussed. 相似文献
42.
43.
This article describes how genetic components of disease susceptibility can be evaluated in case-control studies, where cases and controls are sampled independently from the population at large. Subjects are assumed unrelated, in contrast to studies of familial aggregation and linkage. The logistic model can be used to test collapsibility over phenotypes or genotypes, and to estimate interactions between environmental and genetic factors. Such interactions provide an example of a context where non-hierarchical models make sense biologically. Also, if the exposure and genetic categories occur independently and the disease is rare, then analyses based only on cases are valid, and offer better precision for estimating gene-environment interactions than those based on the full data. 相似文献
44.
PURPOSE: To assess the consistency of ratings assigned by health sciences faculty members relative to community members during an innovative admissions protocol called the Multiple Mini-Interview (MMI). METHOD: A nine-station MMI was created and 54 candidates to an undergraduate MD program participated in the exercise in Spring 2003. Three stations were staffed with a pair of faculty members, three with a pair of community members, and three with one member of each group. Raters completed a four-item evaluation form. All participants completed post-MMI questionnaires. Generalizability Theory was used to examine the consistency of the ratings provided within each of these three subgroups. RESULTS: The overall test reliability was found to be .78 and a Decision Study suggested that admissions committees should distribute their resources by increasing the number of interviews to which candidates are exposed rather than increasing the number of interviewers within each interview. Divergence of ratings was greater within the pairing of community member to faculty member and least for pairings of community members. Participants responded positively to the MMI. CONCLUSION: The MMI provides a reliable protocol for assessing the personal qualities of candidates by accounting for context specificity with a multiple sampling approach. Increasing the heterogeneity of interviewers may increase the heterogeneity of the accepted group of candidates. Further work will determine the extent to which different groups of raters provide equally valid (albeit different) judgments. 相似文献
45.
Routine ultrasound may have a positive effect on obstetric outcome when determination of gestational age and placental localization are combined with evaluation for multiple gestation, congenital anomalies and growth retardation. The potential risk and benefit of obstetric ultrasound must be better understood before this procedure is used as a screening tool in large populations. 相似文献
46.
Inflammation and the Aging Process: Devil or Angel 总被引:1,自引:0,他引:1
Inflammation is often viewed as a pathologic mechanism leading to tissue damage and interference with function, such as the process of chronic tissue scarring or fibrosis. However, it is important to note that inflammation is a crucial component of normal tissue repair as well as being fundamental to the body's defense against infection. Considering inflammation as a "causative agent in aging" belies the underlying mechanisms whereby the acute inflammatory response is necessary for survival, and efforts to reduce and control the inflammatory response leave the host susceptible to infectious agents and improper healing. Chronic inflammation inevitably has initiating mechanisms that include immune, autoimmune, and metabolic pathways, leading to the activation and presence of the host-protective response. It is more appropriate to target the underlying initiating conditions than the inflammatory process that ensues and treat the basic mechanisms of disease rather than interfere in a very important protective mechanism of the host. 相似文献
47.
Jack Yu-Shih Lin Shun-Ling Lin Wei-Lin Chen Ying-Shan Chen 《Ophthalmic surgery, lasers & imaging》2005,36(2):158-162
A 29-year-old man who had been treated for acute anterior uveitis in a local medical office and observed for 1 month presented complaining of distorted vision in his left eye for 1 week. On ophthalmic examination, the anterior segment was relatively quiet with few cells. A posterior segment examination revealed cystoid macular edema and multiple splinter retinal hemorrhages. Results of all laboratory and imaging studies were negative, except for a positive HLA-B27 haplotype. Fluorescein angiography revealed massive leakage in the mid and late phase, consistent with chorioretinitis. Periocular corticosteroid injections and oral prednisolone were administered. The patient responded to the treatment well with subsequent resolution of chorioretinitis 2 months later. Although rare, chorioretinitis can occur in the setting of uveitis associated with HLA-B27 and seems to respond well to corticosteroid treatment. 相似文献
48.
Functional MRI in Epilepsy 总被引:2,自引:2,他引:0
49.
Steven G. E. Marsh Ekkehard D. Albert Walter F. Bodmer Ronald E. Bontrop Bo Dupont Henry A. Erlich Daniel E. Geraghty John A. Hansen Bernard Mach Wolfgang R. Mayr Peter Parham Effie W. Petersdorf Takehiko Sasazuki Geziena M. Th. Schreuder Jack L. Strominger Arne Svejgaard Paul I. Terasaki 《International journal of immunogenetics》2002,29(6):463-515
50.
A bstract Isolated mitral valve replacement using the CarboMedics prosthetic mitral valve (CarboMedics, Inc., Austin, TX) was studied in 13 centers in the United States, Canada, and Scandinavia between 1987 and 1993 in 428 patients with a mean age of 57 ± 14 years. Actuarial survivals at 1, 2, and 5 years were 88.2% and 75.8%. Freedom from events at 5 years were 94.8% for major thromboembolism, 96.6% for thrombosis, and 96.7% for endocarditis. Linearized morbidity rates (events per 100 patient years) for events at > 30 days postoperatively were .51 thrombosis, 1.1 major thromboembolism, and .37 endocarditis. These results at early to mid-term compare favorably with the first generation bileaflet valve. 相似文献