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71.
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The rib is an uncommon site of osteosarcoma. With the use of adjuvant chemotherapy and aggressive surgical resection of the metastatic pulmonary lesions, extrapulmonary metastases are becoming more clinically evident. Primary rib osteosarcoma with extrapulmonary metastasis is exceedingly rare. A case is reported, showing that the pattern of metastasis of rib osteosarcoma is similar to that of primary bone osteosarcoma. The liver metastasis occurred after resection of the metastatic pulmonary lesions. A CT scan of the primary rib lesion and liver metastasis both showed a lace‐like enhancement pattern, its histological appearance corresponding with neoplastic osteoid. With the increasing use of CT abdomen for localization of extrapulmonary metastases, lace‐like enhancement may be seen more readily in the future.  相似文献   
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Pelvic actinomycosis associated with intrauterine devices   总被引:1,自引:0,他引:1  
O'Connor  KF; Bagg  MN; Croley  MR; Schabel  SI 《Radiology》1989,170(2):559-560
The authors describe two women with pelvic pain, long-term use of an intrauterine device, and a pelvic mass due to Actinomyces israelii. The diagnostic imaging findings were nonspecific but included mass effect and mucosal irregularity of the rectosigmoid colon at barium enema examination and complex masses and inflammatory changes at computed tomography and magnetic resonance imaging. Radiologists should be aware of the imaging findings of this potentially lethal but curable condition.  相似文献   
76.
Mangan  KF; D'Alessandro  L 《Blood》1985,66(3):533-541
To define further the role of marrow T suppressor lymphocytes in the pathogenesis of the hypoproliferative anemia in all Rai clinical stages of B cell chronic lymphocytic leukemia (CLL), marrow erythroid progenitor cell (CFU-E and BFU-E) frequency, marrow T gamma lymphocyte frequency per 1,000 nucleated marrow cells, and T cell-erythroid progenitor cell interactions were examined in 30 CLL patients and normal control subjects. As compared with control subjects, decreased numbers of CFU-E and BFU-E were found in patient marrow depleted of neoplastic B cells in all Rai stages of the disease. As a group, Rai stage III through IV patients with or without aplasia (CLL-aplasia) had significantly fewer CFU-E and BFU-E than did Rai O through II stage patients. The numbers of T gamma cells infiltrating CLL marrows were increased 3, 9, and 20 times normal in Rai O through II, Rai III through IV, and CLL-aplasia groups, respectively. Removal of T cells from marrow increased growth of CFU-E and BFU-E in all Rai O through IV patients, but the increase was significant in the CLL-aplasia group only (P less than .05). However, autologous coculture of marrow T cells or T gamma cells but not B cells with marrow B + T-depleted null cells at ratios of 0.2:1 to 1:1 suppressed CFU-E and BFU-E growth in all three patient groups. We conclude that the hypoproliferative anemia occurring in the course of B cell CLL is due to gradual accumulation in the marrow of T gamma lymphocytes which suppress erythroid progenitor cell growth. T gamma cell suppression of erythropoiesis and marrow T gamma cell expansion is detectable in the earliest Rai stages of the disease.  相似文献   
77.
Unger  EC; Gado  MH; Fulling  KF; Littlefield  JL 《Radiology》1987,162(3):789-795
Magnetic resonance (MR) imaging was performed in five monkeys with experimentally induced acute cerebral infarction to define the MR imaging features and correlate these with computed tomographic (CT) findings, laboratory analysis, and histopathologic studies. Acute infarct (2-4 hours after embolization) was generally visible on MR images but not on CT scans. CT at 24 and 48 hours did show the infarcts. In all cases the infarct was more clearly depicted with MR imaging and was visualized as an area of high signal intensity on T2-weighted images. Spectrometric nuclear MR measurements of the postmortem cerebral tissue confirmed prolongation of both T1 and T2 values similar to that calculated from MR images. At postmortem laboratory testing, the area of infarction detected with MR imaging had decreased specific gravity and increased water content, reflecting edema.  相似文献   
78.
INTRODUCTION: Ethanol is teratogenic, interferes with folic acid and is extensively used by young women. Our objective was to determine the effects of ethanol and/or folate deficiency on mouse fetuses. METHOD: In Experiment 1, pregnant mice receiving a commercial diet were divided into three groups: control (C), low ethanol dose (LE, 0.4 g/kg), and high ethanol dose (HE, 4.0 g/kg). In Experiment 2, pregnant mice receiving a folate-free diet (FFD) were divided into three groups: folate deficiency (FD), folate deficiency plus a low ethanol dose (FDLE), and folate deficiency plus a high ethanol dose (FDHE). Groups C and FD received saline and the remaining groups received ethanol administered i.p. from the 7th to the 9th gestational day (GD) and were sacrificed on the 18th GD. RESULTS: In Experiment 1, Group HE presented congenital anomalies, late fetal death (LFD), lower fetal length and weight and placental weight and diameter than Groups C and LE. In Experiment 2, there was a smaller number of live fetuses, a larger number of reabsorptions and LFD, a smaller length and lower fetal weight, placental weight and diameter in Groups FDLE and FDHE than in Group FD. CONCLUSION: In animals receiving a commercial diet, a high ethanol dose is deleterious to the pregnancy, inducing congenital anomalies, intrauterine growth restriction, reduction of the placenta and increased LFD, events that did not occur with the low dose. However, with a folate free diet, a low ethanol dose is as deleterious as a high dose.  相似文献   
79.
BACKGROUND: Expert management of tracheal intubation has become fundamental to the routine practice of pulmonary physicians who work in respiratory intensive care units (ICUs). In Italy, tracheal intubation is not included as part of the training in respiratory medicine, and pulmonary physicians are usually dissuaded from managing intubations. METHODS: We prospectively studied the intubation success rate in 46 consecutive respiratory ICU patients who required either emergency or urgent intubation, conducted by 3 intubation-trained pulmonary physicians in our respiratory ICU. Intubation success was defined as successful tracheal intubation without any of 7 pre-defined complications. RESULTS: There were 17 emergency intubations and 29 urgent intubations. Intubation was successful in 43 of the 46 intubation attempts. Complications occurred in 3 cases: 2 patients needed to be intubated by an anesthesiologist, and 1 patient received fiberoptic intubation. CONCLUSIONS: Pulmonary physicians trained in tracheal intubation can have a high success rate in performing intubation in the respiratory ICU. Collaborative efforts between anesthesiologists and pulmonary physicians are necessary to optimize the training, skill-retention, and back-up for advanced airway management in the respiratory ICU.  相似文献   
80.
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   
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