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Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma   总被引:6,自引:3,他引:6  
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.  相似文献   
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Thyrotrophin (4-256 microU/ml) promoted an increase in the rate of release of radioiodine from the organic iodine pool of cultured porcine thyroid cells in follicular formations. This action of TSH was antagonized by low concentrations of epidermal growth factor (EGF; 0.1-5 nmol/l). The maximal effect of EGF was reached by 0.5 nmol/l. EGF (0.5-5 nmol/l) also inhibited the stimulatory effect of 8-chloro cyclic AMP (0.06-1.0 nmol/l) on radioiodine turnover. Exposure of thyroid cultures to media with a calcium concentration of 17.7 mumol/l (1% of normal) resulted in a very marked increase in the rate of release of radioiodine. The effect of TSH in low-calcium media was to inhibit the increased release of radioiodine, and EGF (0.5 nmol/l) antagonized this inhibitory effect of TSH. The calcium ionophore, A23187, stimulated radioiodine release in a dose-dependent fashion, and EGF (1.7 nmol/l) inhibited this response. Fluid transport in thyroid monolayers was stimulated by prostaglandin E2 (PGE2; 1 mumol/l). EGF (5 nmol/l) also stimulated fluid transport, but antagonized the effect of PGE2 added subsequently. It was concluded that EGF exerted acute antagonistic effects on thyroid cell responses in vitro to cyclic AMP and agents promoting accumulation of cyclic AMP in time-frames too short for these inhibitory effects to be attributable to the dedifferentiative effect of the growth factor.  相似文献   
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STUDY OBJECTIVE: We performed an assessment of hospital preparedness for weapons of mass destruction (WMD) incidents in Federal Emergency Management Agency (FEMA) Region III. METHODS: Interviews of hospital personnel were completed in 30 hospitals. Data collected included level of preparedness, mass decontamination capabilities, training of hospital staff, and facility security capabilities. RESULTS: No respondents believed their sites were fully prepared to handle a biologic incident, 73% (22/30) believed they were not prepared to manage a chemical weapons incident, and 73% believed they were unprepared to handle a nuclear event. If a WMD incident were to occur, 73% of respondents stated a single-room decontamination process would be set up. Four (13%) hospitals (all rural) reported no decontamination plans. WMD preparedness had been incorporated into hospital disaster plans by 27% (8/30) of facilities. Eighty-seven percent (26/30) believed their emergency department could manage 10 to 50 casualties at once. Only 1 facility had stockpiled any medications for WMD treatment. All facilities had established networks of communication. No hospital had preprepared media statements specific to WMD. Nearly one fourth (7/30) stated that their hospital staff had some training in WMD event management. All reported need for WMD-specific training but identified obstacles to achieving this. Seventy-seven percent (23/30) of hospitals had a facility security plan in place, and half were able to perform a hospital-wide lock down. Ninety-six percent (29/30) reported no awareness regarding the threat of a secondary device. CONCLUSION: Hospitals in this sample do not appear to be prepared to handle WMD events, especially in areas such as mass decontamination, mass medical response, awareness among health care professionals, health communications, and facility security. Further research is warranted, including a detailed assessment of WMD preparedness using a statistically valid sample representative of hospital emergency personnel at the national level.  相似文献   
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Cultured porcine thyroid cells, maintained in the differentiated state by dibutyryl cyclic AMP, responded to serotonin (5-HT; 10 nmol/l to 1 mumol/l) with a depolarization of the membrane potential, but did not respond to histamine (100 mumol/l) or dopamine (1 mumol/l). The resting membrane potential of these cells was about -71 mV, maximal concentrations of 5-HT (1 mumol/l) inducing a depolarization to approximately -53 mV. Methysergide or phenoxybenzamine, but not propranolol, abolished the response to 5-HT. Sensitivity to 5-HT was reduced by previous exposure of cultures to TSH, the beta-adrenoceptor agonist salbutamol or 5-HT itself.  相似文献   
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ABSTRACT

Neuroimaging and genomic analysis greatly aid in the identification of young-onset dementia antemortem. We present the case of a 33-year-old female with a 2-year rapid decline to dementia and immobility marked by personality change, executive deficits including compulsions, attention deficit, apraxia, Parkinsonism, and pyramidal signs. She had unique and dramatic calcifications and confluent white matter changes on imaging and was found to have a novel mutation in the colony stimulating factor 1 receptor gene causing adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP). Here, we review ALSP and briefly discuss differential diagnoses.  相似文献   
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A 22-year-old man was admitted with a severe traumatic brain injury developed a hyperacute subdural hematoma (SDH) following attempted brain tissue oxygen monitor placement. This patient was successfully treated by placement of a subdural evacuation portal system (SEPS). The patient presented to a Level I trauma center after a severe bike versus auto accident. On admission, he was found to have a Glasgow Coma Scale (GCS) score of 3. The patient had small areas of intraparechymal hemorrhage as well as suspicion for diffuse axonal injury in the midbrain. Based on the patient’s GCS score, neurological monitoring was indicated as a part of his intensive care unit treatment, however a SDH occurred during an attempted placement of a brain tissue oxygen monitor. This iatrogenic hyperacute SDH after burr hole monitoring device placement was treated with a SEPS drain. The SEPS drain has been shown to provide complete and/or temporary decompression of liquefied SDH. To our knowledge, this is the first report of using the SEPS to treat iatrogenic SDH associated with an intracranial monitoring device. This technique should be added to the armament of treatment options for a neurosurgeon to treat or temporize a hyperacute SDH with increased intracranial pressure in specific patients.  相似文献   
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