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31.
A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern. 相似文献
32.
Malignant fibrous histiocytoma (MFH) is a tumor of late adult life not often recognized as occurring in children. Our search of the English literature produced only 27 well-documented examples occurring in the soft tissues, to which we here add 2 additional cases. Both of our cases displayed the classical storiform-pleomorphic histologic pattern typical of such tumors in adults, and both pursued a malignant and rapidly fatal course. Previous reports of this tumor in children are reviewed, and the differential diagnostic considerations briefly discussed. Overall, the clinical features of MFH in children are similar to those reported in adults, and surgical removal remains the key element of successful therapy. 相似文献
33.
G W Mierau 《Histopathology》1999,35(2):99-101
The histopathological diagnosis of tumours has been transformed by immunohistochemistry. Used with experience and judgement, a panel of antibodies or antisera, combined when necessary with antigen retrieval, will enable the accurate typing of most problematic tumours. This has led many histopathologists to question whether the electron microscope has any residual utility for tumour diagnosis; the machines are large, costly to purchase and maintain, and will accept only minute samples of tissue. The following articles by Mierau and by Eyden, both strong advocates, comment on the current and future role of electron microscopy in tumour diagnosis. 相似文献
34.
Madeline Crnec J. David Cassidy Dale Mierau K. Yong-Hing 《The Journal of the Canadian Chiropractic Association》1986,30(2):83-85
Os odontoideum is an anomaly of the odontoid process and might be congenital or the result of trauma. Symptoms begin at any age, and the clinical presentation is variable. During radiological examination, it is often a chance finding in an unrelated problem, and just such a case is presented here. The patient presented with rheumatoid arthritis and thoracic backache, was found to have C1-2 instability due to an os odontoideum, and surgical stabilization was planned. Os odontoideum is an absolute contraindication to upper cervical manipulation. 相似文献
35.
Knee injuries: high-resolution MR imaging 总被引:5,自引:0,他引:5
Recent technologic advances have made high-resolution magnetic resonance (MR) imaging of the knee a clinical reality. Ten healthy volunteers and 30 patients with suspected knee injuries were imaged using receive-only surface coils and two-dimensional multisection or three-dimensional selective acquisition techniques. Arthroscopic and/or surgical correlation was available in 15 patients. Tears of the cruciate ligament, medial collateral ligament, and meniscus are illustrated. Nonorthogonal views of the anterior cruciate ligament are useful for demonstrating both femoral and tibial attachments in the same section. The posterior cruciate ligament is usually well seen on sagittal views. T2-weighted images are helpful for demonstrating collateral ligament tears and meniscal tears when joint effusion is present. Thin sections (1-5 mm) are necessary to define many meniscal and cruciate tears. High-resolution, thin-section MR imaging can be used to diagnose soft-tissue injuries of the knee and has the potential to become a major imaging method in the evaluation of knee injuries. 相似文献
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38.
Diagnosis and prognosis of early rheumatoid arthritis, with special emphasis on laboratory analysis.
Diagnosis of rheumatoid arthritis (RA) is mainly based on clinical criteria of symmetric polyarthritis of the hands and feet, with morning stiffness lasting usually more than 1 h. Autoantibodies typical for RA, i.e., rheumatoid factors and anti-cyclic citrullinated peptide, and measurements of inflammation add more specific information, especially for early diagnosis, where clinical presentation may be oligosymptomatic involving only a few joints. These laboratory parameters are also relevant for prognosis of disease persistence, functional impairment and radiological progression. 相似文献
39.
HT Lam ; SO Schweitzer ; L Petz ; MH Kanter ; DA Bernstein ; S Brauer ; DV Pascual ; BA Myhre ; IA Shulman ; GW Sun 《Transfusion》1997,37(6):577-584
BACKGROUND: The purpose of this study was to search for a more effective transfusion-monitoring system than the existing system of retrospective peer review. STUDY DESIGN AND METHODS: This research used a study-control, preintervention and postintervention design, to evaluate the effectiveness of a prospective physician self-audit transfusion-monitoring system that functioned without the direct involvement of transfusion service physicians. This research also evaluated the effectiveness of issuing to physicians a memo with transfusion guidelines. Three process indicators were used to assess physician behavior at various stages of the blood-ordering process: 1) the number of crossmatches ordered per admission, 2) the transfusion-to- crossmatch ratio, and 3) the number of blood units returned to the laboratory after physician self-auditing. The study used two outcome indicators to reflect overall blood utilization: 1) the percentage of patients who received red cell transfusions and 2) the number of blood units transfused per recipient each month. RESULTS: The prospective physician self-audit system implemented at the study hospital did not reverse physician transfusion decisions, and the process of issuing to physicians a memo with transfusion guidelines at the control hospital failed to reduce blood usage. However, a transient reduction in blood utilization was observed at the study hospital. CONCLUSION: The reduction was hypothesized to be due to a Hawthorne effect, in which observed behavior is affected by the subject's awareness of the research study. 相似文献
40.
目的:建立恢复种植体周围骨缺损的自体骨碎末骨移植材料的实验模型。方法:实验于2005-08/2006-04在大连医科大学动物实验基地(辽宁省重点实验室)完成。①实验材料:健康杂交家犬5只,体质量15~20kg。Bio-Oss骨移植材料为引导骨/组织再生多孔骨无机材料,白色颗粒状,颗粒大小1.0~2.0mm。②实验方法:拔除家犬下颌第1,2,3前臼齿,3个月后行种植术。预备种植体窝,每只犬左右两侧各预备4个,共40个。在每个种植窝内,各植入种植体钛钉1枚,共40枚。用种植转孔时收集的自体骨碎末、Bio-Oss骨移植材料及两者1∶1混合骨碎末恢复种植体颊侧单壁人为骨缺损,以未植骨作空白对照。③实验评估:第9周时观察各组骨量的恢复情况、X线片观察牙槽骨高度、骨小梁致密度及骨整合情况,亚甲基蓝-碱性品红法观察组织学变化。结果:5只家犬钛钉均无脱落,均纳入结果分析。①一般情况:9周时,创口愈合均良好,钛钉稳定,总存留率为100%。骨缺损处已有不同程度恢复,与正常骨组织无明显差别。②9周时各组骨缺损量的测量结果:植入自体骨碎末、Bio-Oss骨移植材料、混合骨碎末及空白对照组的平均骨缺损量分别为1.8125、1.6975、1.5025、2.6375mm。植入混合骨碎末的平均骨缺损量最小,说明恢复最佳。③X线观察骨量的恢复情况:40颗钛钉外周均与骨组织紧密接触,愈合良好。不同组间未见明显骨质密度区别。④组织学观察骨量的恢复情况:低倍镜下见所有钛钉均被周围淡红色的致密骨组织紧密包绕,种植体与骨组织间无蓝色的软组织,产生了直接骨结合界面。结论:应用家犬建立自体骨碎末移植材料恢复种植体周围骨缺损的实验模型效果理想。 相似文献