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61.
BACKGROUND: Intravenously administered perfluorocarbon (PFC) emulsions increase oxygen solubility in plasma. PFC might therefore temporarily replace red cells (RBCs) lost during intraoperative hemorrhage. In patients who have undergone hemodilution, the return of autologous blood may be delayed by the administration of PFC, and autologous RBCs may be saved for transfusion after surgical bleeding is stopped and PFC is cleared by the reticuloendothelial system. STUDY DESIGN AND METHODS: In 22 anesthetized, hemodiluted dogs (hemoglobin [Hb] 7 g/dL) breathing 100-percent O2, an intraoperative volume-compensated blood loss was simulated. The efficacy of three therapeutic regimens in maintaining tissue oxygenation was compared: 1) RBC group (n = 7): maintenance of a Hb > 7 g per dL by transfusion of autologous RBCs; 2) PFC group (n = 7): bolus application of a second-generation PFC emulsion (60% wt/vol perflubron) and further acute normovolemic hemodilution (ANH) to a Hb of 3 g per dL; and 3) control group (n = 7): further ANH alone to a Hb of 3 g per dL. Systemic and myocardial oxygenation status and tissue oxygenation were assessed. RESULTS: Autologous RBCs transfused to maintain a Hb of 7 g per dL preserved hemodynamics and tissue oxygenation during blood loss. In the PFC and control groups, heart rate and cardiac index increased significantly in response to further ANH. Tissue oxygenation was not different in the PFC and the RBC groups. Direct comparison of the PFC and control groups revealed better tissue oxygenation in the PFC group, as reflected by significantly higher mixed venous, coronary venous, and local tissue pO2 on liver and skeletal muscle. CONCLUSION: Bolus intravenous administration of 60- percent (wt/vol) perflubron emulsion and further hemodilution from a Hb of 7 g per dL to one of 3 g per dL were as effective as autologous RBC transfusion in maintaining tissue oxygenation during volume-compensated blood loss designed to mimic surgical bleeding.  相似文献   
62.
Verruciform xanthoma associated with squamous cell carcinoma   总被引:4,自引:0,他引:4  
Verruciform xanthoma (VX) is a rare lesion of unknown etiology that is typically solitary and predominantly located within the oral cavity. Less commonly, they arise on the skin, with the majority of cases occurring in anogenital sites. They can be confused clinically with verruca vulgaris, condyloma, leukoplakia, verrucous carcinoma, and squamous cell carcinoma. Histologic features include acanthosis with uniform elongation of the rete ridges and xanthomatous cells that lie in and are typically confined to the papillary dermis. Although epidermal atypia is not a characteristic finding, we describe an unusual case of VX that has features of both VX and squamous cell carcinoma. In addition, there was a VX with typical histologic characteristics located at a separate site in the same patient. This case is also the first to our knowledge to be reported on the neck and axilla and is the third case associated with cutaneous graft versus host disease secondary to bone marrow transplant for acute lymphoblastic leukemia.  相似文献   
63.
Palisaded neutrophilic granulomatous dermatitis (PNGD) is an entity that has not been clearly defined either clinically or histopathologically. It is seen in patients with rheumatoid arthritis and other connective tissue diseases. In the past, many cases of PNGD have been described under several different names including palisaded neutrophilic and granulomatous dermatitis, linear subcutaneous bands, interstitial granulomatous dermatitis with cutaneous cords and arthritis, rheumatoid papules, and Churg-Strauss granuloma. We report 7 additional cases of PNGD. Clinically, 6 patients presented with erythematous to violaceous plaques, papules, and nodules on multiple body sites; one presented with subcutaneous linear bands on the shoulder. Five had rheumatoid arthritis; one had adult-onset Still's disease; and one showed clinical signs of rheumatoid arthritis, although serologically the rheumatoid factor was negative. On histologic examination, a spectrum of changes was observed ranging from urticaria-like infiltrates to leukocytoclastic vasculitis and granuloma annulare with neutrophils. We report these cases to expand the histologic spectrum of this entity and to further delineate the different forms of clinical presentation.  相似文献   
64.
A detailed analysis of the results of the international annual International Committee for Dermatopathology-Union Européene des Médecins Specialistes dermatopathology examination was undertaken to identify clues for further improvement. The analysis covered 5 consecutive years (2006-2010) and involved a total of 860 questions (591 common questions and 269 uncommon questions) and 181 participants. It focused on the overall performance of the participants, the performance per part of the examination (theoretical or practical), the performance per format of question (multiple choice or open), the performance per dermatopathological topic, and the performance per professional background (dermatologist or pathologist). The overall performance of the participants was high (on average 75% correct answers in 2006 and 85% correct answers in the subsequent years). In the theoretical part of the examination, the topics of vascular diseases and lichenoid dermatoses scored better than the average of all topics, and the topics of cutaneous lymphoproliferative diseases and melanocytic disorders scored worse. In the first practical part (interpretation of images), dermatologists outperformed pathologists, especially on providing a diagnosis (open question format) of clinical images. In the second practical part (microscopical examination), the topics of vascular diseases, granulomatous diseases, including necrobiotic and degenerative and metabolic diseases scored better than the average of all topics, and the topic of infectious diseases scored worse. The results of this detailed analysis provide an excellent feedback to the examination committee that will be used to consider the adjustment of parts and/or topics of the examination that showed a deviant performance by the participants. In addition, it is recommended to give more attention to the postgraduate education of certain dermatopathological topics, including cutaneous lymphoproliferative diseases, melanocytic disorders, and infectious diseases.  相似文献   
65.
66.
Retiform hemangioendothelioma (RH) is a rare vascular neoplasm most often occurring in the limbs of middle-aged females. This entity is characterized by infiltrative vascular spaces arranged in a pattern similar to the rete testis. RH differs from angiosarcoma by lacking cytologic atypia and high mitotic rates. This neoplasm frequently recurs but rarely metastasizes. RH tumor cells react with vascular endothelial markers CD31, CD34, and factor VIII-related antigen. A review of the English literature provides only one attempt at staining RH with D2-40, a marker of endothelium of lymphatic vessels, which was negative, and one reported staining of RH with lymphatic endothelial marker VEGFR-3, which was positive. The etiology of RH is unknown. RH has previously been considered closely related to Dabska tumors, which are positive for lymphatic endothelial marker D2-40. We stained 4 RHs with mouse monoclonal antibodies against D2-40 and CD31 and 3 of the 4 RHs with vascular endothelial growth factor receptor 3 (VEGFR-3), to further evaluate whether RH had lymphatic differentiation, in addition to vascular differentiation. Three of the 4 RH biopsies failed to demonstrate D2-40, none expressed VEGFR-3, whereas CD31 was strongly positive, suggesting that RH is a vascular entity which usually does not have lymphatic differentiation, but may rarely express D2-40.  相似文献   
67.
Granuloma annulare is a dermatologic condition of unknown etiology that has been associated with systemic diseases and reported to be a paraneoplastic manifestation. Two patients with generalized granuloma annulare as an initial manifestation of chronic myelomonocytic leukemia are herein described. We suggest that chronic myelomonocytic leukemia should be added to the list of systemic diseases associated with generalized granuloma annulare.  相似文献   
68.
The association of atypical fibroxanthoma (AFX) and mycosis fungoides (MF) has never been reported. We report a 77-year-old female who was referred for Mohs micrographic surgery (MMS) of an AFX on the right hand. At the time of presentation, this patient had stage III MF, with erythroderma and palpable lymph nodes. Our patient's AFX measured 1.5x2.8 cm. The tumor was removed by MMS with clear margins. The pathologic specimen revealed a relatively well-circumscribed neoplasm in the upper dermis composed of atypical spindle cells with pleomorphism, hyperchromatic nuclei, and brisk mitotic activity. Immunohistochemical stains were focally positive for CD68, and negative for S-100, Melan-A, desmin, smooth muscle actin and neurofilament. Perilesional skin revealed epidermal hyperplasia, parakeratosis, and multiple epidermotropic lymphocytes with enlarged and hyperchromatic nuclei. One year after the initial MMS, our patient developed another tumor on the right hand, which measured 4x6 mm. This neoplasm underwent a fusiform excision with clear margins. Histological examination revealed evidence of MF and an AFX. To our knowledge, this is the first report of an AFX arising in a patient with MF.  相似文献   
69.
70.
Doctors' willingness to refer elderly patients for elective surgery   总被引:6,自引:0,他引:6  
OBJECTIVES: We aimed to examine the relationship between doctors' willingness to refer elderly patients for elective surgical operations and patients' age, comorbidity, institutionalization, living habits and signs of dementia. METHOD: A random selection of 837 medical doctors in Finland (response rate 56%) received a postal questionnaire consisting of 18 vignettes, i.e. imaginary patient cases. Respondents were asked whether they would refer the patient on the vignette for elective surgical operation, treat the patient conservatively, or choose some other alternative. In the vignettes, the age of patients was randomly varied between 65 and 85, at 5-year intervals, to provide eight different questionnaires, and each respondent obtained one of them. RESULTS: The proportion of doctors willing to refer the patients for surgery was inversely related to the patients' age: in all the vignettes, doctors said they would refer fewer patients in the oldest age groups. Almost all the doctors claimed they would refer healthy, home-dwelling persons aged 65-70 years for operations. In the oldest age groups of patients, the doctors' willingness to refer was highest for cataract operations (69%) and hip prosthesis operations (63%), but only 18% of doctors would refer such patients for coronary by-pass operations. Comorbidity and institutionalization were associated with fewer doctors referring the patients: the proportion of doctors willing to refer these patients was about half that of those willing to refer otherwise healthy and home-dwelling patients. Smoking by patients also decreased the proportions of doctors willing to refer, but moderate signs of dementia in an elderly patient with cataract were associated with only a slight decrease in referring. CONCLUSIONS: Doctors are less willing to refer old patients for elective surgery, but comorbidity, patients' lifestyle and institutionalization have a greater effect on referrals than age.   相似文献   
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