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411.
背景和目的颅内动脉粥样硬化可造成众多患者发生缺血性卒中。过去10年间血管内治疗技术已经取得突破性进展,能够开展颅内动脉粥样硬化性狭窄的血管内治疗。采用血管成形术和支架辅助阻管成形术治疗颅内动脉粥样硬化性狭窄的患者例数不断增加。但是鉴于目前血管成形术和支架辅助血管成形术治疗狭窄性和闭塞性颅内动脉粥样硬化仍缺乏普遍认可的临床和放射学评估以及皿管内治疗技术及预后的规范,此文就是提供该方面报告标准、术语和书面定义的共识性建议。报告摘要报告标准是在技术评价委员会、神经介入外科学会、介入放射学会、美国神经外科医师协会和神经外科医师代表大会的脑血管外科分会、美国神经科学会的卒中和介入神经病学分会的联合写作组共同起草完成。对1997年1月-2007年12月间,美国国立图书馆医学文献数据库(PubMed)进行计算机检索,旨在确定已发表的狭窄性颅内动脉粥样硬化的神经介入治疗中,能用作质量评价基准的资料。我们尽可能地确定影响神经介入治疗成功及并发症可能性的危险调节变量。对狭窄性和闭塞性颅内动脉粥样硬化进行麻管内治疗的临床试验设计中,不同临床和技术问题可能影响血管内治疗的疗效,此文章为这些问题提供相关的理论基础。该指南中包括对血管内治疗试验报告标准的建议。虽然制定规范和标准主要是出于研究用途,但是这也将有助于临床实践,还适用于所有相关的出版物。结论总之,报告标准提出的建议将有助于构建有效的研究数据库,同时促进产生科学可靠的研究结果,使相似研究之间或内部能够进行可靠的比较。存某些情况下,为报告和出版的一致性,本文中的定义可能是写作组专家的共识性建议。这些建议将促使不同研究组的结果具有直接可比性。  相似文献   
412.
Tissue Magnesium Levels and the Arrhythmic Substrate in Humans   总被引:1,自引:0,他引:1  
Magnesium and Arrhythmias. Introduction: Magnesium deficiency has been implicated in the pathogenesis of sudden death, but the investigation of arrhythmic mechanisms has been hindered by difficulties in measuring cellular tissue magnesium stores.
Methods and Results: To see if magnesium deficiency is associated with a propensity toward triggered arrhythmias, we measured tissue magnesium levels and QT interval dispersion (as an index of repolarization dispersion) in 40 patients with arrhythmic complaints. Magnesium was measured in sublingual epithelium using X-ray dispersive analysis. QT interval dispersion was assessed on 12-lead surface F-XCs in all patients, and programmed stimulation was performed in 28. The sublingual epithelial magnesium level ([Mg]i), but the not the serum level, correlated Inversely with QT interval dispersion in 40 patients (r = 0.58, P < 0.0.5); in 12 patients undergoing repeat testing on therapy, the change in magnesium also correlated inversely with the change in QT dispersion (r = 0.61, P < 0.05). Patients with left ventricular ejection fractions > 40% had significantly higher tissue magnesium and lower QT dispersion (34.5 ± 0.5 mEq/L, 81 ± 8 msec) than those with left ventricular ejection fractious < 40% (32.7 ± 0.5 mEq/L, P < 0.01, and 114 ± 9 msec, P < 0.05). There was no difference in either [Mg]i, or QT dispersion in the 16 patients with inducible monomorphic ventricular tachycardia versus the 12 noninducible patients.
Conclusion: Reduced tissue magnesium stores may represent a significant risk factor for arrhythmias associated with abnormal repolarization, particularly in patients with poor left ventricular systolic function, but may not represent a risk for excitable gap arrhythmias associated with a fixed anatomic substrate (e.g., monomorphic ventricular tachycardia).  相似文献   
413.
Harrison  DE; Lerner  CP; Spooncer  E 《Blood》1987,69(4):1021-1025
Hemopoietic precursors are heterogeneous with respect to their capacity for self-renewal and long-term repopulating ability. Bone marrow cultures produce a variety of precursors over many weeks, including CFU- S; however, it is important to determine whether these populations retain the functional ability shown by fresh marrow. The most primitive precursor or stem cells have the most long-term repopulating ability. We here describe direct measurements of this ability in cells from marrow cultures by using competitive repopulation assays. Cultured adherent cells repeatedly showed less capacity than fresh marrow cells to repopulate erythropoiesis in irradiated recipients, whereas cultured suspension cells consistently had less capacity than adherent cells. Concentrations of macroscopic CFU-S measured at nine or 12 days were similar in cultured adherent and suspension cells and generally lower than those in fresh marrow. In every experiment, the long-term repopulating ability of the marrow cells used was substantially reduced after transfer into tissue culture. Thus, primitive stem cells may not proliferate in such cultures despite extensive production of CFU-S and more differentiated cell types.  相似文献   
414.
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416.
To determine the histopathologic correlates of alterations in the rotator cuff at magnetic resonance (MR) imaging, 13 cadaveric shoulders (in subjects aged 26-83 years at the time of death) underwent MR imaging in the coronal oblique plane at 1.5 T with proton-density- and T2-weighted spin-echo sequences. Areas corresponding to sites of MR imaging alterations were then examined histologically. Increased signal intensity on proton-density-weighted images (without further increased signal intensity on T2-weighted images) and an indistinct margin at the articular side of the supraspinatus tendon corresponded to eosinophilic, fibrillar, and mucoid degeneration and scarring. Areas of increased signal intensity on T2-weighted images were associated with severe degeneration and disruption of the supraspinatus tendon. Although other authors have suggested that certain MR findings are indicative of tendinitis, the histologic data in this study were not those of active inflammation but rather tendon degeneration.  相似文献   
417.
Two cases of primary osteosarcoma of the lung are presented. In one case, the radiologic, clinical, and cytologic findings led to a preoperative diagnosis of undifferentiated carcinoma of the lung. In the second case, a lung nodule was discovered during postchemotherapy follow-up in a patient with lymphoma. Fine needle aspiration in the second case showed lymphoma, and further chemotherapy was instituted; however, persistent growth of the nodule prompted a resection. Microscopic examination of the resected tumors in both cases revealed histologic features of high-grade osteosarcoma. Flow cytometric analyses of the primary tumors showed abnormal hyperdiploid deoxyribonucleic acid populations in accordance with those seen in high-grade malignant neoplasms. Immunohistochemical studies supported a mesenchymal origin for these tumors. These tumors shared clinical features with other reported cases of primary osteosarcoma of the lung such as large size at diagnosis, occurrence in older individuals, and aggressive behavior.  相似文献   
418.
Between 1982 and 1987, 139 patients with primary carcinoma of the lung were treated with pneumonectomy. Thirty-nine patients (28%) were in clinical stage I, 10 (7%) were in clinical stage II, and 90 (65%) were in clinical stage III. Overall actuarial 3-year survival was 33%. Actuarial 3-year survival for patients in clinical stage I was 44%; for those in clinical stage II, 48%; and for those in clinical stage III, 28%. Risk factors for operative mortality examined included preoperative forced vital capacity (FVC) of 2.13 L or less and forced expiratory volume in 1 second (FEV1) of 1.65 L or less, percent predicted FVC of 64% or less and FEV1 of 65% or less, predicted postoperative FVC of 1.31 L or less and FEV1 of 0.89 L or less, and predicted postoperative percent predicted FVC of 41% or less and FEV1 of 34% or less. Operative deaths occurred only in clinical stage III patients (7/90 or 8%). Patients with compromised pulmonary function based on one or more of the examined risk factors were at increased risk for death (2/10) compared with patients with better pulmonary function (5/80 or 6.25%). Actuarial 3-year survival for high-risk clinical stage III patients ranged from 0% to 16% compared with 28% for other clinical stage III patients. Thirty-day mortality for pathological stage III patients was 6.3% (5/79), and 3-year actuarial survival was 24%. No patient in pathological stage III who was at high risk survived beyond 3.1 years. Select individuals with adequate pulmonary function and stage III disease can achieve substantial long-term survival after pneumonectomy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
419.
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