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21.
Acute appendicitis: CT and US correlation in 100 patients   总被引:18,自引:1,他引:18  
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The historical development of deceased organ donation, transplantation, and organ procurement organizations is reviewed. The concept of transplantation, taking parts from one animal or person and putting them into another animal or person, is ancient. The development of organ transplantation brought on the need for a source of organs. Although many early kidney transplants used kidneys from living donors, these donors could not satisfy the ever-growing need for organs, and extrarenal organs were recovered only from deceased donors. This need for organs to satisfy the great demand led to specialized organizations to identify deceased donors, manage them until recovery occurred, and to notify transplant centers that organs were available for their patients. The functions of these organ procurement organizations expanded to include other required functions such as education, accounting, and compliance with state and federal requirements. Because of the shortage of organs relative to the demand, lack of a unified organ allocation system, the perception that organs are a national resource and should be governed by national regulations, and to improve results of organ procurement organizations and transplant centers, the federal government has regulated virtually all phases of organ procurement and transplantation.  相似文献   
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OBJECTIVES: To describe the split orbicularis myomucosal flap and to review our center's experience with this technique for large defects of the lower lip. METHODS: All patients presenting to the senior author (Y.D.) for lower lip reconstruction using this flap were reviewed in a retrospective fashion. RESULTS: A total of 14 patients with a minimum follow-up of 6 months (mean, 3.4 years; range, 6 months to 5 years) underwent lower lip reconstruction using the split orbicularis myomucosal flap from May 1999 to May 2004. Twelve of the defects arose as a result of cancer resection (squamous cell carcinoma [n = 8], basal cell carcinoma [n = 3], and melanoma [n = 1]), and 2 arose secondary to trauma. The defect crossed the vermilion in two thirds of the cases, extending for a variable distance onto the cutaneous portion of the lower lip. The defect size varied from 50% to 80% of the transverse dimension of the lower lip (mean, 68%) and involved the commissure in 4 patients. There were no flap failures, facial nerve palsies or paralyses, oral incompetence, or need for scar revision in any of our study population. CONCLUSION: The split orbicularis myomucosal flap is a reliable method of reconstructing significant defects of up to 80% of the lower lip with minimal risks of microstomia or functional impairment.  相似文献   
25.

Background

Midclerkship self-evaluations (MCSEs) require students to reflect on their knowledge, skills, and behaviors. We hypothesized that MCSEs would be consistent with supervisor midpoint evaluations during a surgical clerkship.

Methods

MCSEs of 153 students who completed our surgery clerkship in 2 academic years were compared with supervisor midclerkship evaluations. The quantitative domains of the MCSE and supervisor evaluation were compared for accuracy. Identified areas of strengths and weakness were evaluated for thematic consistency.

Results

Student MCSE scoring was accurate across evaluated domains most of the time; when students were inaccurate, they tended to underrate themselves. Students and supervisors most often identified cognitive skills as areas for improvement and noncognitive skills predominated as student strengths.

Conclusions

Medical students can accurately identify their strengths and weaknesses in the context of an MCSE. Based on these findings, knowledge acquisition and application by medical students in the clinical setting should be emphasized in undergraduate medical education.  相似文献   
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A patient with a long history of arthritis developed pneumonia. Two weeks into her hospital course, the patient developed effusions in her knee and wrist that yielded cultures positive for Mycoplasma pneumoniae. To our knowledge, this is the third reported case of M pneumoniae isolation from a joint and the first report of isolation of M pneumoniae from two joints in a patient without hypogammaglobulinemia. The evidence suggests that in individuals with atypical pneumonia and joint effusions, M pneumoniae should be considered as a source of infection.  相似文献   
30.
Sawada  Y; Fass  DN; Katzmann  JA; Bahn  RC; Bowie  EJ 《Blood》1986,67(5):1229-1239
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels.  相似文献   
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