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1.
A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.  相似文献   
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Neural basis for verb processing in Alzheimer's disease: an fMRI study   总被引:2,自引:0,他引:2  
Patients with probable Alzheimer's disease (AD) have difficulty understanding verbs. To investigate the neural basis for this deficit, the authors used functional magnetic resonance imaging to examine patterns of neural activation during verb processing in 11 AD patients compared with 16 healthy seniors. Subjects judged the pleasantness of verbs, including MOTION verbs and COGNITION verbs. Healthy seniors and AD patients both activated posterolateral temporal and inferior frontal regions during judgments of verbs. These activations were relatively reduced and somewhat changed in their anatomic distribution in AD patients compared with healthy seniors, particularly for the subcategory of MOTION verbs, but AD patients showed minimal activation in association with COGNITION verbs. These findings imply that poor performance with verbs in AD is due in part to altered activation of the large-scale neural network that supports verb processing.  相似文献   
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Thirty-eight children with Hodgkin’s disease have been treated over the past 8yr with either intensive radiotherapy orcombination chemotherapy (MOPP), depending on their initial stage. The mediansurvival of the entire group of childrenhas not yet been reached, as 63% are stillalive, but it will be in excess of 58 mo.Median survivals by stage are as follows:stage I, greater than 46 mo; stage II,greater than 46 mo; stage III, 35 mo; andstage IV, 26.7 mo. Although the numbersof children are small, these results appearsignificantly superior to published reportsutilizing less intensive radiotherapy andsingle-agent chemotherapy and suggestthat intensive radiotherapy for localizeddisease and combination chemotherapy foradvanced disease may, at present, be thepreferred forms of therapy for Hodgkin’sdisease in childhood.

Submitted on October 16, 1972 Revised on December 26, 1972 Accepted on December 28, 1972  相似文献   
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In 38 patients with non-Hodgkin's lymphoma, involvement of the central nervous system (CNS) by malignant lymphoma developed during an eight year period. All patients had lymphomatous meningitis; clinical involvement of the spinal nerves or cranial nerves suggested the diagnosis. Spinal fluid was abnormal in 97 per cent of the patients although a positive cytology could be documented in only 67 per cent by lumbar puncture. The histology in 82 per cent of the patients was diffuse. Involvement of the CNS in nodular lymphoma was uncommon (3 per cent), and the histology in virtually all of these patients had converted to diffuse. At the time of diagnosis of CNS disease, 95 per cent of the patients had other evidence of advanced disease; 66 per cent had bone marrow involvement. In only 18 per cent of the patients did CNS disease develop while they were in clinical remission. Eighty-five per cent of the patients treated with whole brain irradiation and intrathecal chemotherapy had a good clinical response. Knowledge of these risk factors permits definition of a group of patients who may benefit from CNS prophylaxis.  相似文献   
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Weiss  HJ; Turitto  VT; Baumgartner  HR 《Blood》1986,67(2):322-330
Patients whose platelets are deficient in glycoprotein (GP) Ib, IIb- IIIa (thrombasthenia), or granule substances (storage pool deficiency, SPD) were studied to define further the properties of platelets that mediate platelet adhesion and thrombus formation on subendothelium. Both nonanticoagulated and citrated blood were exposed to everted, de- endothelialized rabbit vessel segments under controlled flow conditions and shear rates varying from 650 to 3,300 sec-1. Morphometry was used to measure platelet thrombus dimensions and the percentage of the subendothelial surface covered with contact (C) or spread (S) platelets. Adhesion was defined as C + S. The results in SPD demonstrated (1) reduced thrombus dimensions in delta-SPD (pure dense granule deficiency) in proportion to the magnitude of the dense granule defect; (2) an even greater reduction in thrombus dimensions in patients with combined deficiencies of alpha and dense granules (alpha delta-SPD); and (3) impaired platelet adhesion at several conditions in alpha delta-SPD and, in delta-SPD, a hematocrit-dependent impairment of adhesion in citrated blood at 2,600 sec-1. In thrombasthenia, platelets were present as a monolayer on the subendothelial surface in both nonanticoagulated and citrated blood, indicating an absolute requirement for GPIIb-IIIa in promoting platelet-platelet interaction at all shear rates and perfusion times. Two types of abnormalities in platelet-vessel wall interactions were observed. In nonanticoagulated blood, the percentage of platelets in the C phase was consistently increased at all shear rates, but C + S values were normal. These observations indicate that platelets deficient in GPIIb-IIIa do not spread normally on the subendothelial surface exposed to nonanticoagulated blood. With citrated blood, the C + S value in thrombasthenia was reduced at both 800 and 2,600 sec-1, as in von Willebrand's disease, and a similar degree of reduction (about 50%) was observed in normal blood treated with a monoclonal antibody to GPIIb- IIIa. The findings, together with theoretical considerations, are consistent with an hypothesis that GPIIb-IIIa mediates the spreading of platelets on subendothelium following the initial attachment through GPIb and that GPIIb-IIIa may be considered an adhesion site on the platelet membrane. Abnormalities of GPIIb-IIIa may, depending on the conditions of study, result in either increased values of C platelets or decreased values of C + S. The results of the study further suggest that a complex interaction of platelet granule factors and membrane GP mediate platelet adhesion and thrombus formation.  相似文献   
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