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51.
52.
The significance of an isolated central nervous system relapse, occurring as first relapse in children with acute lymphoblastic leukemia 总被引:1,自引:0,他引:1
H Behrendt E F van Leeuwen C Schuwirth R J Verkes J Hermans A van der Does-van den Berg E R van Wering 《Cancer》1989,63(10):2066-2072
In a retrospective study, which comprised the whole Dutch childhood population of approximately 3 million children, the authors assessed the influence of an isolated meningeal relapse, occurring as first relapse, together with some patient and treatment characteristics on prognosis in 142 children with acute lymphoblastic leukemia (ALL). Until their first relapse, patients were initially treated according to standard protocols, whereas the treatment for relapse was heterogeneous. Concerning the probability of achieving a second complete remission (CR) it appears that the duration of the first CR is the single most important prognostic factor. The duration of the first CR is also the most important factor with regard to the duration of the second CR, upon which also age and sex have a significant influence. Concerning the survival from the time of central nervous system (CNS) relapse, again the duration of the first CR appears to be the most important prognostic factor, followed by age and the institution of systemic reinduction treatment. Other factors, such as initial leukocyte count, attainment of first CR within 48 days, type of reinduction treatment, and the cerebral spinal fluid (CSF) blast count at the time of relapse, have a less important, but nevertheless significant influence on survival. The median survival from the time of CNS relapse is 25 months, the 5-year survival is 25%, whereas the ultimate survival will be less than 20%. From 90 patients who developed second or subsequent relapses, 75% experienced a bone marrow relapse during the follow-up period. From this study the authors conclude that CNS relapse in children with ALL carries a grave prognosis, which requires the institution of intensive retreatment programs. 相似文献
53.
Acetyladenylate plays a role in controlling the direction of flagellar rotation. 总被引:27,自引:8,他引:19
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A J Wolfe M P Conley H C Berg 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(18):6711-6715
Cells of Escherichia coli deleted for genes that code for the transducers and all the known cytoplasmic Che proteins except CheY responded reversibly to the addition of acetate by spinning their flagellar motors clockwise. By varying growth conditions and using metabolic inhibitors and mutants deficient in acetate metabolism, this effect was shown to require acetate-CoA synthetase [acetate:CoA ligase (AMP-forming); EC 6.2.1.1], an enzyme that catalyzes the formation of acetyl-CoA from acetate by an acetyladenylate intermediate. A mutant deficient in this enzyme but retaining the chemotaxis genes was deficient for chemotaxis. Thus, acetyladenylate appears to play a role in generating clockwise rotation at the level of CheY or the motor. 相似文献
54.
Calciphylaxis – a topical overview 总被引:3,自引:0,他引:3
G Arseculeratne† AT Evans‡ SM Morley† 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):493-502
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis. 相似文献
55.
56.
Mousa H. M. Van Den Berg M. M. Caniano D.A. 《世界核心医学期刊文摘》2006,2(5):15-15
经盲肠造口顺行性结肠灌洗术可作为重度排便障碍患儿的一种治疗选择。该研究目的是报道31例有功能性便秘(n=9)、Hirschsprung病(n=2)、肛门闭锁(n=5)、脊柱异常(n=8)、肛门闭锁合并脊髓栓系综合征(n=7)患儿行盲肠造口术的4年临床经验。回顾性收集包括并发症、顺行性结肠灌洗术的应用、症状与生活质量等各方面资料。31例患儿中有30例成功地安置了盲肠造口导管。功能性便秘(P=0.01)、肛门闭锁(P〈0.01)及脊髓异常(P=0.04)患儿便秘的发生率明显降低。功能性便秘及肛门闭锁患儿的生活质量有所提高。经皮及外科置管的并发症无显性差异。对于各种原因造成排便障碍的患儿,通过盲肠造口的顺行性结肠灌洗术可使患儿的症状与生活质量得到明显改善。 相似文献
57.
58.
H K Berg 《Maryland medical journal (Baltimore, Md. : 1985)》1990,39(7):675-678
A review of the literature shows adenocarcinoma of the anal canal to have a poor outcome. Radical surgery is the treatment of choice for this disease. 相似文献
59.
Blinded clinical evaluation of positron emission tomography for diagnosis of probable Alzheimer's disease. 总被引:5,自引:0,他引:5
W J Powers J S Perlmutter T O Videen P Herscovitch L K Griffeth H D Royal B A Siegel J C Morris L Berg 《Neurology》1992,42(4):765-770
We evaluated the sensitivity and specificity of positron emission tomography for diagnosis of probable Alzheimer's disease under conditions similar to those encountered in the routine clinical practice of nuclear medicine. We obtained tomographic images of regional cerebral blood flow from three groups of subjects: (1) 13 subjects, ages 69 to 84, who had probable Alzheimer's disease diagnosed by validated clinical criteria; (2) 15 subjects, ages 57 to 77, who had Parkinson's disease without dementia; and (3) 11 subjects, ages 65 to 83, who were normal. Three blinded reviewers, who had not previously seen the images, categorized them as normal, bilateral temporoparietal flow defects typical of Alzheimer's disease, or other abnormality. Consensus interpretation demonstrated sensitivity of 0.38 (5/13) and specificity of 0.88 (23/26) for identifying patients with probable Alzheimer's disease. Thus, the criterion of bilateral temporoparietal reduction in cerebral blood flow used in this study did not have sufficient sensitivity to be of clinical value. While other criteria may be developed to improve diagnostic accuracy, clinical utility can be established only by testing for validity in patients with a full spectrum of complicating neurologic and psychiatric conditions for whom diagnosis is uncertain and who are then followed longitudinally to determine clinical outcome or pathologic findings. 相似文献
60.
M R L?wik H van den Berg J Schrijver J Odink M Wedel P van Houten 《Journal of the American College of Nutrition》1992,11(6):673-681
The nutritional status (assessed by anthropometric indices, and biochemical and hematological variables in blood) of three groups of elderly women (aged > or = 65 years) was evaluated within the framework of the Dutch Nutrition Surveillance System. The groups were composed of women living in a nursing home (n = 51), women living in service flats and receiving their dinners from the nursing home kitchen (n = 29), and women living independently (n = 52). Mean blood levels of folate, pyridoxal 5'-phosphate, 25-hydroxyvitamin D, alpha-tocopherol, vitamin C, albumin, selenium and total cholesterol were significantly (p < 0.05) lower among nursing home women. Among these women a biochemical deficiency was frequently found for 25-hydroxyvitamin D (73%), pyridoxal 5'-phosphate (57%), vitamin C (38%), selenium (30%) and folate (28%). These nutritional risks were largely independent of each other. Since folate and pyridoxal 5'-phosphate were associated with several clinicochemical indicators, health status may be an important determining factor for this unfavorable situation. Low 25-hydroxyvitamin D concentrations were associated with limited exposure to ultraviolet radiation and nonusage of vitamin D supplements. We conclude that dietary intake variables are not the only determinants of a marginal nutritional status among nursing home women. Use of foods with a high nutrient density should be encouraged, whereas other preventive measures are needed to improve vitamin D status. 相似文献