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31.
PURPOSE: Diamond-Blackfan anemia (DBA) is a congenital pure red cell aplasia, usually presenting in infancy or early childhood. A review of the literature strongly supports a predisposition to hematopoietic malignancy. Recently, solid tumors have been reported, some attributable to hemosiderosis and/or androgen therapy. Two cases of osteogenic sarcoma have also been documented. An analysis from the Diamond-Blackfan Anemia Registry was performed to evaluate the cancer risk in patients with DBA. METHODS: The Diamond-Blackfan Anemia Registry of North America (DBAR) is a comprehensive database of patients with DBA enrolled, after informed consent, through outreach to pediatric hematologists and family groups. The patients and/or their families complete a detailed questionnaire, and a review of medical records and telephone interviews are performed to complete and clarify the information provided. RESULTS: Of the 354 patients registered in the DBAR, there were six patients meeting the accepted diagnostic criteria for DBA who were found to have malignancies. Three patients had osteogenic sarcoma diagnosed, one with myelodysplastic syndrome, one with colon carcinoma, and one with a soft tissue sarcoma. CONCLUSION: There appears to be an association of osteogenic sarcoma with DBA. A young age at presentation may be a feature of DBA-associated osteogenic sarcoma. Because of the immaturity of the database, the actuarial risk for osteogenic sarcoma and other cancers in individuals with DBA cannot be ascertained. Speculation is made regarding the nature of the molecular defect leading to the association of DBA and osteogenic sarcoma.  相似文献   
32.
The objectives of this transmission electron microscopy study of peri-implant tissues retrieved at revision arthroplasty were to (1) determine the size distribution of intracellular polyethylene particles, and (2) assess the cellular response to phagocytosed polyethylene particles as revealed by the condition of the cellular organelles. The frequency distributions of intracellular polyethylene particle sizes for 15 cases of total hip replacement showed that more than 75% of the particles had lengths of less than 0.5 microm. More than 90% of the particles were less than 1.0 microm in size. In comparison, the frequency distribution for the particles in cellscomprising tissue retrieved from three total knee replacement prostheses showed that only 43% of the particles were less than 0.5 microm in length and 72% were less than 1 microm in size. There was no statistically significant difference in the mean particle length between the specimens from the hip and knee patients. The majority of the cells containing polyethylene were without signs of degeneration. The cytoplasmic and nuclear membranes were intact. Several electron lucent voids which once contained polyethylene particles were seen surrounded by several healthy appearing mitochondria, which displayed sharp membranes and intact cristae. There were no signs of a cytotoxic response to polyethylene at the ultrastructural level.  相似文献   
33.
BACKGROUND: Primary care providers (PCPs) have limited training in recognizing common skin disorders, and additional emphasis may be placed on laboratory evaluation, including skin biopsies. METHODS: Primary care providers in Miami, Fla, were surveyed regarding skin biopsy and excision practices and histologic interpretation. They then participated in an examination, using 20 high-quality color photographs of common dermatologic disorders. RESULTS: Of the 80 PCPs who participated, 42% currently do skin biopsies and consult general pathologists for interpretation. Another 20% of PCPs intend to do biopsies within the next 5 years. Only 33% prefer to have a dermatopathologist interpret histopathology. We found no correlation between PCPs' scores on diagnostic testing and whether they do skin biopsies. CONCLUSION: Nearly all PCPs doing skin biopsies in our study sample use general pathologists to interpret histopathology. The limited training in clinical dermatology of both PCPs and general pathologists may result in compromised clinical-pathologic correlation.  相似文献   
34.
An update on hypercoagulable disorders   总被引:3,自引:0,他引:3  
Venous thrombosis is a cause of considerable morbidity and is often responsible for chronic venous disorders that frequently lead to visits to dermatologists and others involved in wound healing. Over the past several years, many new causes of thrombophilia have been identified and have dramatically altered the approach to patients presenting with thrombosis. Newly described abnormalities associated with thrombophilia include the syndrome of activated protein C resistance, the prothrombin 20210A mutation, hyperhomocysteinemia, and elevated levels of coagulation factors VIII and XI. Clinicians can now frequently determine causes of thromboses that have previously been deemed idiopathic.  相似文献   
35.
PURPOSE: To report a case of malattia leventinese involving subretinal hemorrhage. METHODS: Case report. RESULTS: Two weeks after initial presentation, the visual acuity of this 34-year-old man decreased to LE: 20/100. Funduscopic evaluation revealed a subretinal hemorrhage involving the center of the foveal in the left eye that was interpreted as secondary to a neovascular membrane on fluorescein angiography. The patient did well after the removal of the submacular material by pars plana vitrectomy. CONCLUSION: Patients with malattia leventinese may occasionally present with submacular hemorrhage. Prompt diagnosis and intervention may enhance the patient's chance for visual improvement.  相似文献   
36.
37.
Leukocytoclastic vasculitis, presenting with palpable purpura, is a relatively common problem encountered by both primary care practitioners and dermatologists. A variety of potential etiologies exists and includes autoimmune, neoplastic, and infectious causes. We report a case of leukocytoclastic vasculitis that led to the diagnosis of acute hepatitis B, perhaps acquired through colonoscopy.  相似文献   
38.
We used a contact Nd:YAG laser with a sapphire tip to perform blepharoplasties in rabbits, and to cut bone in the orbital rim. All procedures were performed easily and without intraoperative hemorrhage.  相似文献   
39.
Coronary artery disease (CAD) is a major cause of morbidity and mortality after elective surgical repair of abdominal aortic aneurysm (AAA). The aim of this study was to determine the relationship between the extent of CAD observed in coronary angiograms (more than 50% stenosis) and the frequency of postoperative myocardial ischemic complications in a consecutive series of 84 patients who underwent elective AAA repair. Ninety-four percent of the patients with clinical evidence of CAD had significant disease as observed in coronary angiograms and eight patients had left main CAD. Seventy-two patients underwent AAA repair with a mortality rate of 1.4%; five patients had preliminary myocardial revascularization, and AAA surgery was not recommended for four patients because of severe cardiac disease. Postoperative myocardial ischemic complications occurred in 13.4% of the patients who had undergone surgery--almost exclusively in patients with clinical evidence of CAD. Both myocardial ischemia and preoperative intervention were more frequent in patients with double- or triple-vessel disease than in patients with less extensive disease. Patients with symptoms and with double- or triple-vessel CAD have a high risk of developing myocardial ischemia after AAA surgery. Preliminary myocardial revascularization may be beneficial in this group of patients.  相似文献   
40.
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