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71.
Autologous bone marrow transplantation (ABMT) makes it possible to escalate the dose of cytotoxic treatment to a lethal range. Disease- free survival (DFS) following myeloablative therapy and ABMT has been shown to be superior to conventional treatment in high risk patients with acute myelogenous leukemia (AML). It was the purpose of the present study to compare hematopoietic reconstitution, actuarial DFS, and relapse rate of patients transplanted in first complete remission (CR) of AML with those in second or subsequent CR, and to evaluate transplant related mortality. Fifty-two patients with AML, 22 in first CR (low risk) and 30 in second or subsequent CR (high risk), underwent total body irradiation (12.1 to 16.7 Gy) and cyclophosphamide (CY) treatment (200 mg/kg) followed by ABMT. The autograft was incubated with the active CY derivative Mafosfamide (ASTA Werke, Bielefeld, Federal Republic of Germany) to reduce the number of possibly contaminating clonogenic tumor cells. All patients showed three lineage engraftments with platelet recovery observed as being the slowest. The transplant related death rate was low at 5.8%. There was no significant difference in the kinetics of polymorphonuclear (PMN) cell or platelet reconstitution between the low and high risk patient subgroups. The estimated probability of DFS (relapse) after ABMT in first CR was 61% (36%) compared with 34% (65%) in second or subsequent CR, the longest follow-up being 55 months and 57 months, respectively (median follow-up 31 months and 19 months, respectively). ABMT offers a stable long-term DFS when performed in first CR with no relapses occurring in over a year after transplantation. Six later relapses, however, were seen after ABMT in second or subsequent CR, although DFS was not statistically different from that of first remission patients (P = .72).  相似文献   
72.
A prospective evaluation of regional cerebral blood flow (rCBF) (ipsilateral middle cerebral artery distribution) was determined using a 133Xe clearance technique in 31 ASA P.S. II-III patients anesthetized with isoflurane-50% N2O in O2 for carotid endarterectomy. Each patient was monitored with 16-channel EEG throughout anesthesia and surgery. Critical rCBF was defined as that flow below which EEG signs of ischemia occurred. Critical rCBF (T1/2 method of analysis) was less than 10 ml X 100 g-1 X min-1 (mean +/- SE 5.9 +/- 1.2) in the six patients in whom transient EEG changes occurred at the time of temporary surgical carotid artery occlusion. No EEG changes occurred with occlusion in the other 25 patients; mean (+/- SE) occlusion rCBF in this group was 18.9 +/- 1.3 ml X 100 g-1 X min-1 (P less than 0.001). Preocclusion flows were not significantly different in the two groups. Critical rCBF during isoflurane anesthesia was less than that previously determined during halothane anesthesia (18-20 ml X 100 g-1 X min-1), and is compatible with the effects of isoflurane on CMRO2 and CBF.  相似文献   
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We describe two type 2 diabetic patients with unilateral emphysematous pyelonephritis who responded to medical treatment alone. Escherichia coli was isolated in both patients. The presence of gas was confirmed early by ultrasound and CT scan of abdomen. Following treatment, good functional recovery was demonstrable in the affected kidneys by isotope renogram. We stress the need for early diagnosis of this condition and aggressive treatment with broad spectrum antibiotics.  相似文献   
74.
目的:临床局部辐射条件下会造成非辐射区域组织及细胞功能损害,最为突出的是对造血功能的影响。实验建立60Coγ射线左半身辐射动物模型,观察局部电离辐射对其非辐射区域骨髓巨核细胞的影响。方法:实验于2003-10/2005-03在解放军第三军医大学辐照中心和全军复合伤研究所完成。①实验动物:6~8周龄SPF级雄性昆明小鼠180只,随机数字表法分为正常对照组、全身辐射组、左半身辐射组、全身屏蔽辐射组,45只/组。②实验方法:全身辐射组小鼠固定于辐射架内;左半身辐射组小鼠麻醉后固定体位,用铅砖屏蔽右半身;全身屏蔽辐射组小鼠麻醉固定体位,用铅砖屏蔽全身。以60Coγ射线一次性辐射,剂量率68.46cGy/min。正常对照组不作任何干预。③实验评估:辐射后不同时相检测小鼠血清丙二醛含量及超氧化物歧化酶活性变化,计数外周血血小板,检测骨髓巨核祖细胞集落形成单位,观察骨髓组织病理改变及CD41a、CD61的表达。结果:全身辐射组第8天死亡2只,第9天死亡4只,其余各组无脱失。①外周血血小板计数:辐射后第2,7天,左半身辐射组外周血血小板数量显著低于正常对照组(P<0.01),但高于全身辐射组(P<0.01)。②血清丙二醛含量及超氧化物歧化酶活性变化:辐射后第2,9天,左半身辐射组血清丙二醛含量显著高于正常对照组(P<0.01),低于全身辐射组(P<0.01);血清超氧化物歧化酶活性显著低于正常对照组(P<0.01),高于全身辐射组(P<0.01)。③骨髓巨核祖细胞集落形成单位的变化:与正常对照组比较,辐射后6h左半身辐射组非辐射侧的巨核祖细胞集落形成单位显著降低(P<0.01),高于全身辐射组及左半身辐射组(P<0.01)。④骨髓组织病理改变:正常对照组有核细胞比例较高,分布均匀,并见多量散在分布的细胞龛;辐射2d后,左半身辐射组非辐射侧骨髓有核细胞较正常对照组减少,但好于全身辐射组、左半身辐射组。⑤骨髓CD41a及CD61表达的变化:辐射后2d与正常对照组比较,左半身辐射组非辐射侧骨髓CD41a及CD61阳性细胞数和相对荧光强度均显著降低(P<0.01),但高于全身辐射组、左半身辐射组(P<0.01)。结论:局部电离辐射作用后,可导致小鼠非辐射区域骨髓巨核细胞增殖能力降低,血小板减少,产生功能障碍。氧自由基激活可能参与了该损伤过程。  相似文献   
75.
Calcific aortic stenosis is now the main cause of aortic stenosis in the majority of patients, due to declining incidence of rheumatic fever. Risk factors such as hyperlipidemia play an important role in the progression of aortic stenosis. According to the most recent American College of Cardiology/American Heart Association guidelines, peak velocity greater than 4 m/sec, a mean gradient of more than 40 mmHg and a valve area of less than 1.0 cm(2) is considered hemodynamically severe aortic stenosis. Aortic valve surgery promptly should be done in symptomatic patients due to dismal prognosis without operation. Features such as high aortic valve calcium and positive exercise test identify asymptomatic patients who would benefit from early aortic valve surgery. Due to improvement in surgical techniques and better prosthesis, aortic valve surgery can now be offered at low risk to a selected group of asymptomatic patients with severe aortic stenosis. Currently percutaneous aortic valves are used in very high-risk patients with severe symptomatic aortic stenosis. Their role may expand in the future, depending on the improvements in design and operator experience. Whether advances in molecular cardiology lead to novel therapies in preventing calcific aortic stenosis in the future remains to be seen.  相似文献   
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Current research suggests that Ca2+ flux into the neuron may be a critical factor in the genesis of seizures. We report herein the influence of nimodipine, a selective central nervous system calcium channel blocker, in 60 rabbits with seizures that had been induced through ischemia, postischemia reperfusion, pentylenetetrazol, and bicuculline. In 30 animals subjected to 4 hours of ischemia, 9 of the 15 control animals had seizures in comparison with 1 of the 15 treated animals (P less than 0.005). Five animals with reperfusion seizures demonstrated similar results. In 10 animals in which a convulsant was applied topically to both cerebral hemispheres, unilateral intracarotid injection of nimodipine arrested seizures in that hemisphere alone, whereas the control contralateral hemisphere continued to have electrical seizure activity (P less than 0.001). Both placebo and verapamil were ineffective. These results suggest that Ca2+ influx is a common biochemical precipitant for various types of experimental seizures. Selective central nervous system calcium channel blockers may prove to be a new class of anticonvulsant agents.  相似文献   
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