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41.
Hasegawa DK; Bennett AJ; Coccia PF; Ramsay NK; Nesbit ME; Krivit W; Edson JR 《Blood》1980,56(4):585-595
Factor V deficiency has been identified in 8 of 8 patients 7--20 yr of age, with Philadelphia-positive (Ph1+) chronic myelogenous leukemia (CML). In these 8 patients, factor V deficiency was not due to hepatic dysfunction, factor V inhibitors, or disseminated intravascular coagulation. In 3 patients, factor V activity rose 10%--12% (0.10--0.12 U/ml) after the infusion of 28--31 ml/kg body weight of fresh frozen plasma (FFP). The rise persisted less than 14 hr. The mean measured postinfusion rise in factor V was 18% of the expected rise calculated from the volume of FFP infused in the patients' plasma volume. In 4 patients, a small transient rise in factor V activity occurred after splenectomy or plateletpheresis. Factor V deficiency was completely corrected after a marked reduction in bone marrow cellularity in 2 patients with Ph1+ CML treated with extensive chemotherapy, total body irradiation, and bone marrow transplantation. Factor V deficiency was retrospectively observed in 6 of 20 patients, ages 20--80 yr, with Ph1+ CML and 3 of 6 patients with other myeloproliferative disorders. The factor V deficiency appears to be associated with the large myeloid- megakaryocytic cell mass characteristic of CML and other myeloproliferative disorders. 相似文献
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Karen L. Clark Matthew Loscalzo Peter C. Trask James Zabora Errol J. Philip 《Psycho-oncology》2010,19(12):1313-1320
Background: Pancreatic cancer is the fourth leading cause of cancer‐related death in the United States, unsuccessful in significantly improving 5‐year survival. A diagnosis of pancreatic cancer may be associated with increased psychological distress, yet remarkably little is known about the degree of psychological distress experienced by these patients at the time of diagnosis and treatment. Method: In a cross‐sectional study, 304 patients with pancreatic cancer and 7749 patients with other cancer diagnoses completed the Brief Symptom Inventory (BSI) or the Brief Symptom Inventory‐Shortened Version (BSI‐18) and the Problem Common Checklist (PCL) during outpatient registration. Sociodemographic characteristics were collected from patients' clinical files. Results: A higher percentage of pancreatic cancer patients reported elevated distress across each subscale of the BSI and BSI‐18 when compared with those diagnosed with other cancer diagnoses as a group. The most notable difference was established on the depression subscale, with 28.8% of pancreatic patients reporting elevated depression compared with 18.5% of other cancer diagnoses. In pancreatic patients, a significant difference was also found in the percentage of males endorsing high depression levels when compared with females (34.0 vs 22.6%, p<0.05). Conclusions: Pancreatic cancer patients demonstrate elevated levels of psychological distress. This should alert providers to be vigilant in evaluating patients for distress and to provide appropriate referrals. The endorsement of fatigue and pain, along with the observed gender differences, suggest that early distress management interventions may need to include components targeted to these issues. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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复合自适应滤波器用于体感诱发电位信噪比的提高 总被引:1,自引:0,他引:1
本研究以可靠、快速提取体感诱发电位为目标,试图解决相干叠加方法既费时又不能反映体感诱发电位时变特征的缺点。运用以自适应噪声减法器和自适应增强器为基础构造的复合自适应滤波器提取体感诱发电位。仿真实验表明,运用复合自适应滤波器可实现从强噪声背景中快速提取体感诱发电位,能更快地识别体感诱发电位的潜伏期及幅值,并且系统性能稳定。 相似文献
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Role of extracellular adenosine triphosphate in the cytotoxic T- lymphocyte-mediated lysis of antigen presenting cells 总被引:4,自引:0,他引:4
The lysis of antigen presenting cells (APCs) by cytotoxic T lymphocytes (CTLs) may be one mechanism whereby an immune response is downregulated by Staphylococcus superantigens. Disappearance of monocytes/macrophages from staphylococcal enterotoxin A (SEA)-activated peripheral blood mononuclear cell (PBMC) cultures, but not from control PBMC cultures was seen by flow cytometry. Recently, adenosine triphosphate (ATP) has been described as an effector molecule in CTL-mediated lysis of some murine tumor target cells. We have also shown that ATP caused the lysis of human macrophages, and that treatment of cells with interferon gamma (IFN gamma) rendered macrophages significantly more sensitive to ATP than untreated cells. To show that this purine nucleotide may play a role in modulating the immune system, we generated human CTLs that were stimulated with SEA, and used them as effector cells against SEA-pulsed autologous macrophages. CTLs were found to specifically lyse SEA-pulsed macrophages, while control, unpulsed, macrophages were unaffected. The addition of hexokinase, an enzyme that hydrolyzes ATP, significantly abrogated the killing of SEA-pulsed cells during the assay. In examining the mechanism of cytotoxicity, electron microscopy showed that macrophages incubated with both ATP and CTLs underwent necrosis, rather than apoptosis. From these results, it is suggested that ATP is released from CTLs during antigen presentation, and that IFN gamma- activated macrophages, which are inherently more sensitive to this mediator, are readily lysed and therefore removed from circulation, thus downregulating an immune response. 相似文献
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In the past 10 years, a number of authors have expressed concern that surgeons are abdicating their traditional role of providing preoperative and postoperative care in surgical intensive care units. To study today's private practice environment, we took a survey. Questionnaires were sent to the chiefs of surgery and the nurse managers of the surgical intensive care units at 188 non-university-affiliated hospitals throughout the United States. Results show that surgeons do not have the principal managing role in the intensive care unit for surgical patients in 70% to 75% of the hospitals. Results also indicated that surgeons are relinquishing their responsibilities in the direct care of the preoperative and postoperative critically ill patients. Three main reasons are given for this: (1) an ever-increasing body of critical care knowledge plus complex technology, (2) a lack of economic incentive, and (3) professional liability. To reverse this trend, these three areas must be addressed. 相似文献