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991.
In order to increase the availability and affordability of radioimmunotherapy of refractory or relapsed non-Hodgkins lymphoma, we developed and evaluated radioiodinated rituximab in an ongoing physician-sponsored Phase II Clinical Trial. The chimeric 1gG(1) anti CD 20 monoclonal antibody rituximab was radiolabeled with iodine-131 using a modified Chloramine T method with high radiochemical purity (98% +/- 0.82) and preservation of immunoreactivity. All patients received therapeutic loading doses of unlabeled rituximab (375 mg/m(2)) immediately prior to administration of tracer (200 MBq (131)I) or therapy (1.7-4.3 GBq (131)I) activities of (131)I-rituximab to provide additive immunotherapy and enhance tumor uptake of the radiolabeled antibody. Objective response rate (ORR) was 71% in 35 patients with a median follow-up of 14 months (range 4-28 months). Complete remission (CR) was achieved in 54% of patients, with median duration 20 months. Toxicity evaluation included an additional 7 patients followed for at least 3 months. Tracer dosimetry studies were performed in each patient and the whole body radiation absorbed dose was limited to a mean prescribed dose (MPD) of 0.75 Gy. Myelosuppression was reversible and in only 2 of 42 patients was grade IV hematological toxicity observed. No hemopoietic support was required in any patient. There was no instance of hemorrhage or infection in this group of patients in each of whom individual prospective dosimetry was performed prior to (131)I rituximab radioimmunotherapy for relapsed or refractory non-Hodgkins lymphoma.  相似文献   
992.
Non-Hodgkin lymphomas associated with acquired immunodeficiency syndrome are heterogeneous. Recently, a novel subtype of non-Hodgkin lymphoma occurring mostly in patients with acquired immunodeficiency syndrome has been described and designated as plasmablastic lymphoma. The histomorphologic and immunophenotypic findings of this distinct subtype of non-Hodgkin lymphoma have been characterized previously. Most patients present with oral cavity involvement. We report a case of plasmablastic lymphoma presenting as a lung tumor. To our knowledge, this is the first case report of this unusual subtype of diffuse large B-cell lymphoma in this location.  相似文献   
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Aims: Effective communication enhances team building and is perceived to improve the quality of team performance. A recent publication from the Resuscitation Council (UK) has highlighted this fact and recommended that cardiac arrest team members make contact daily. We wished to identify how often members of this team communicate prior to a cardiopulmonary arrest. Method: A questionnaire on cardiac arrest team composition, leadership, communication and debriefing was distributed nationally to Resuscitation Training Officers (RTOs) and their responses analysed. Results: One hundred and thirty (55%) RTOs replied. Physicians and anaesthetists were the most prominent members of the team. The Medical Senior House Officer is usually nominated as the team leader. Eighty-seven centres (67%) have no communication between team members prior to attending a cardiopulmonary arrest. In 33%, communication occurs but is either informal or fortuitous. The RTOs felt that communication is important to enhance team dynamics and optimise task allocation. Only 7% achieve a formal debrief following a cardiac arrest. Conclusion: Communication between members of the cardiac arrest team before and after a cardiac arrest is poor. Training and development of these skills may improve performance and should be prioritised. Team leadership does not necessarily reflect experience or training.  相似文献   
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Fractures of the calcaneus with associated locked dislocation of the posterior facet have been previously described. Two patients with a calcaneal fracture with a locked dislocation of a portion of the posterior facet were treated with minimally invasive open reduction and percutaneous screw fixation of the fragment with cannulated screws. Both patients had satisfactory reductions and healed the fractures without any soft-tissue complications. This technique can be a useful addition to the armamentarium of the surgeon treating these injuries, especially in the patient at high risk for wound complications.  相似文献   
999.
16Alpha-hydroxyestrone (16alpha-OHE(1)), an endogenous estrogen metabolite, is associated with increased bone density in postmenopausal women. This study was designed to evaluate the long-term activity of this metabolite on bone, uterus, and serum cholesterol in an animal model for postmenopausal bone loss. A preliminary dose-response study performed in weanling rats determined 2000 microg/kg/day to be the optimal dose of 16alpha-OHE(1) for studying estrogenic effect on bone. The long-term experiment was performed in 6-month-old animals that were either sham-operated or OVX. The OVX rats were implanted sc with 60-day continuous-release carrier, 17beta-estradiol (E(2)) (33 microg/kg/day) or 16alpha-OHE(1) pellets (2000 microg/kg/day). OVX decreased uterine weight, increased body weight, serum cholesterol, and all dynamic bone histomorphometric measurements in cortical and cancellous bone, and resulted in a 54% bone loss at the tibial metaphysis. E(2) completely prevented OVX-induced bone loss, suppressed bone turnover, and induced uterine hypertrophy and hypercholesterolemia. 16alpha-OHE(1) acted as an E(2) agonist on bone, suppressing bone formation and resorption. However, the estrogen metabolite lowered serum cholesterol and was only a partial E(2) agonist on uterine weight and epithelial cell height. These results suggest that 16alpha-OHE(1) is an estrogen agonist on bone and may be responsible, in part, for the cholesterol-lowering activity attributed to estrogen. As a consequence of its skeletal effects, older women who produce high levels of 16alpha-OHE(1) could have a lower risk for developing postmenopausal osteoporosis than women who produce less-active estrogen metabolites.  相似文献   
1000.
The effects of marijuana on brain perfusion and internal timing were assessed using [15O] water PET in occasional and chronic users. Twelve volunteers who smoked marijuana recreationally about once weekly, and 12 volunteers who smoked daily for a number of years performed a self-paced counting task during PET imaging, before and after smoking marijuana and placebo cigarettes. Smoking marijuana increased rCBF in the ventral forebrain and cerebellar cortex in both groups, but resulted in significantly less frontal lobe activation in chronic users. Counting rate increased after smoking marijuana in both groups, as did a behavioral measure of self-paced tapping, and both increases correlated with rCBF in the cerebellum. Smoking marijuana appears to accelerate a cerebellar clock altering self-paced behaviors.  相似文献   
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