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The techniques specific to peroperative fluorocholangiography are discussed based on an experience of 632 cholangiograms and an estimation has been made of the associated radiation doses to staff and patients. Rapid and accurate information can be obtained during fluorocholangiography using appropriate techniques with acceptably low radiation hazards.  相似文献   
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After nearly a year of preparation, 'Therapeutic Communication', the first nursing unit in our new Bachelor of Nursing degree was taught for the first time in 1988. The unit has developed and grown since this time, with both educational and financial factors determining such things as design of student materials and assessment mode. The geographically scattered--and often isolated--students are formally recognised for their individuality and their personal and professional life experiences, and given choices within the unit of what they want to learn and how they will present this material, through introduction of a learning contract as part of the unit assessment. Difficulties encountered by these students in maintaining their self-esteem when moving from the demanding and complex world of clinical nursing to the arena of tertiary study are discussed. The provision of speedy, comprehensive feedback with general as well as specific guidance with essay writing and referencing, focuses on the process skills many nurses lack as they enter this unit. The applicability of therapeutic communication to clinical practice and the diversity of projects undertaken by students within the limits of the unit demonstrate its appeal to a wide range of registered nurses. Some of the often ignored or minimised factors that differentiate external study from on-campus work are highlighted for both students and unit facilitator, and the creation of an in-house booklet to assist students in developing their skills in external study is outlined.  相似文献   
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The development of the brachial spinal cord was studied in the marsupial Macropus eugenii (tammar wallaby) on postnatal days 1-34. On day 1 the spinal cord was histologically immature, with a deep central canal, proliferating neuroepithelium and roof and floor plates. The lateral motor column had formed, and forelimb muscles contained primary myotubes. The spinal cord gradually attained a mature appearance between days 1-34. The results confirm the suitability of the wallaby spinal cord for studies of early mammalian development.  相似文献   
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PURPOSETo document differences in the cerebral proton MR spectra of patients with early and late stages of human immunodeficiency virus (HIV) infection.METHODWe studied the relative N-acetyl-aspartate (NAA) levels by localized proton spectroscopy of the parietooccipital region of the brain in 43 HIV-seropositive patients, including 26 with an acquired immunodeficiency syndrome (AIDS)-defining diagnosis, and in eight control subjects.RESULTSReduced relative NAA levels were shown in those HIV-1-seropositive patients: 1) with AIDS against HIV-1-seropositive patients without AIDS (P < .04); 2) with HIV-1-associated cognitive/motor complex against neurologically healthy patients (P < .007); 3) with encephalopathic changes on MR against those with normal imaging (P < .001); and 4) on follow-up against their results on initial study (P < .03).CONCLUSIONSBy clinical (Centers for Disease Control classification) and radiologic (MR evidence of white-matter disease) criteria indicating late-stage HIV infection, reduced relative levels of NAA have been demonstrated. Spectroscopic abnormalities can be quantitatively tracked with time. This paper demonstrates the clinical use of detecting NAA as a putative in vivo measure of the neuronal loss that has been demonstrated in postmortem studies of patients with AIDS. This neuronal loss, which is believed to underlie the HIV-1-associated cognitive/motor complex, is thought to be attributable directly or indirectly to the presence of HIV in the brain. Proton spectroscopy may serve as a quantitative noninvasive indicator of this aspect of cerebral involvement in HIV disease.  相似文献   
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Summary We enrolled children with acute lymphoblastic leukemia (ALL) in a Pediatric Oncology Group (POG) pilot study to monitor erythrocyte (RBC) methotrexate (MTX) and folate (F) levels before and during treatment. The mean value for RBCF at diagnosis was 0.86±0.46 nmol/ml RBC in the 214 patients who achieved remission and 1.21±0.74 nmol/ml RBC in the 10 patients who did not (P=0.020). Folate levels tended to increase during remission induction, but they dropped following an intensive consolidation with methotrexate to levels that were sustained throughout chemotherapy treatment. Methotrexate levels reached mean values of approximately 0.15 nmol/ml RBC at the end of an intensive methotrexate consolidation, then fell to levels that were sustained throughout maintenance therapy. There was a weak correlation between improved event-free survival and higher RBCMTX levels after consolidation, but no correlation was found between improved survival and the level of RBCMTX or RBCF during maintenance therapy. A larger study with more complete data is needed to determine whether RBCMTX or RBCF might be useful in predicting event-free survival in patients with ALL.This work was supported in part by grants from the National Cancer Institute and the National Institute of Health (CA-30969, CA-28476, CA29139, CA-159-89, and CA-33587)  相似文献   
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