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81.
Prompt initial bone marrow engraftment was observed in 10 lethally irradiated dogs receiving infusions of 9.8 to 30.0 x 109 allogeneic marrow cellsstored at -80 C. in dimethyl sulfoxide. The 3 recipients of bone marrow fromunrelated donors, mismatched by canine histocompatibility testing, subsequently rejected their grafts and died within 16 days with marrow hypoplasia.The 3 dogs with matched unrelated donors and the 4 with matched littermate donors all showed sustained marrow engraftment. Evidence of marrowrepopulation by allogeneic cells was obtained by cytogenetic studies in oneand by change to donor red cell type in 3 instances.

Submitted on December 16, 1968 Accepted on January 28, 1969  相似文献   
82.
Linker  CA; Ries  CA; Damon  LE; Rugo  HS; Wolf  JL 《Blood》1993,81(2):311-318
We have studied the use of a new preparative regimen for the treatment of patients in remission of acute myeloid leukemia (AML) with autologous bone marrow transplantation. Chemotherapy consisted of busulfan 1 mg/kg every 6 hours for 4 days (total dose, 16 mg/kg) on days -7 through -4 followed by an intravenous infusion over 6 to 10 hours of etoposide 60 mg/kg on day -3. Autologous bone marrow, treated in vitro with 100 micrograms/mL of 4-hydroperoxycyclophosphamide, was infused on day 0. We have treated 58 patients up to the age of 60 years, 32 in first remission, 21 in second or third remission, and 5 with primary refractory AML unresponsive to high-dose Ara-C, but achieving remission with aggressive salvage regimens. Of the first remission patients, there has been 1 treatment related death and 5 relapses. With median follow-up of 22 months, the actuarial relapse rate is 22% +/- 9% and disease-free survival is 76% +/- 9% at 3 years. Patients with favorable French-American-British (FAB) subtypes (M3 or M4 EO) did especially well, with no relapses seen in 15 patients observed for a median of 30 months. Actuarial relapse rate at 3 years was 48% for first remission patients with less favorable FAB subtypes. Of patients in second or third remission, there were 5 treatment related deaths and 4 relapses. With median follow-up of 22 months, the actuarial relapse rate is 25% +/- 11% and disease-free survival is 56% +/- 11% at 3 years. Four of five primary refractory patients died during treatment and 1 remains in remission with short follow-up. These preliminary data are very encouraging and, if confirmed, support the use of autologous purged bone marrow transplantation using aggressive preparative regimens as one approach to improve the outcome of adults with AML.  相似文献   
83.
Ball  ED; Mills  LE; Coughlin  CT; Beck  JR; Cornwell  GG d 《Blood》1986,68(6):1311-1315
Second or third chemotherapy-induced remissions in acute myelogenous leukemia (AML) are limited by early relapse of the leukemia. We developed monoclonal antibodies (MoAbs) that are cytotoxic to myeloid leukemia cells to treat bone marrow from these patients ex vivo for autologous transplantation. In this pilot study, bone marrow was harvested from ten patients with AML in remission, treated with one or two complement-fixing MoAbs, PM-81 and AML-2-23, which react with myeloid differentiation antigens, incubated with rabbit complement, and cryopreserved. These MoAbs were chosen because they have broad reactivity with AML cells but not with pluripotent progenitor cells. At the time of transplant, 6 patients were in second complete remission, 1 each was in third complete or partial remission, and 2 were in early first relapse. The patients were treated with cyclophosphamide (60 mg/kg a day for 2 days) and total body irradiation (200 cGy twice a day for 3 days) and given infusions of MoAb-treated bone marrow. Full bone marrow reconstitution was observed in eight patients; two patients did not recover platelets. Seven of the ten patients are surviving and disease-free at 21.0, 15.0, 13.0, 10.0, 6.0, 3.0, and 2.0 months posttransplant. Treating bone marrow with MoAbs to myeloid differentiation antigens does not interfere with pluripotential stem cell engraftment. Longer follow-up and a controlled study are necessary to prove that the apparent efficacy of this therapeutic approach in some patients is attributable to MoAb-mediated killing of leukemia cells.  相似文献   
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86.
The Thrombolysis In Myocardial Infarction (TIMI) frame count is a relative index of coronary flow that measures time by counting the number of frames required for dye to travel from the ostium to a standardized coronary landmark in a cineangiogram filmed at a known speed (frames/s). We describe a new method to measure distance along arteries so that absolute velocity (length ÷ time) and absolute flow (area × velocity) may be calculated in patients undergoing percutaneous transluminal coronary angiography (PTCA). After PTCA, the guidewire tip is placed at the coronary landmark and a Kelly clamp is placed on the guidewire where it exits the Y-adapter. The guidewire tip is then withdrawn to the catheter tip and a second Kelly clamp is placed on the wire where it exits the Y-adapter. The distance between the 2 Kelly clamps outside the body is the distance between the catheter tip and the anatomic landmark inside the body. Velocity (cm/s) may be calculated as this distance (cm) ÷ TIMI frame count (frames) × film frame speed (frames/s). Flow (ml/s) may be calculated by multiplying this velocity (cm/s) and the mean cross-sectional lumen area (cm2) along the length of the artery to the TIMI landmark. In 30 patients, velocity increased from 13.9 ± 8.5 cm/s before to 22.8 ± 9.3 cm/s after PTCA (p <0.001). Despite TIMI grade 3 flow both before and after PTCA in 18 patients, velocity actually increased 38%, from 17.0 ± 5.4 to 23.5 ± 9.0 cm/s (p = 0.01). For all 30 patients, flow doubled from 0.6 ± 0.4 ml/s before to 1.2 ± 0.6 ml/s after PTCA (p <0.001). In the 18 patients with TIMI grade 3 flow both before and after PTCA, flow increased 86%, from 0.7 ± 0.3 to 1.3 ± 0.6 ml/s (p = 0.001). Distance along coronary arteries (length) can be simply measured using a PTCA guidewire. This length may be combined with the TIMI frame count to calculate measures of absolute velocity and flow that are sensitive to changes in perfusion. TIMI grade 3 flow is composed of a range of velocities and flows.  相似文献   
87.
Among men who have sex with men (MSM), sexual compulsivity has been associated with higher frequencies of sexual behaviors that may increase risk for transmission of HIV and other sexually transmitted infections (STI). In a Midwestern region where social and community resources for MSM are relatively diffuse, the patterns of partner-seeking and sexual behavior, and their relations to sexual compulsivity, may be different than findings from most other assessments of men in large urban areas. Using a community-based participatory approach (CBPR) and a cross-sectional survey, quantitative data were collected between November 2006 and January 2007 from 504 men related to sexual compulsivity, sexual partner-seeking, and sexual behavior. We sought to explore sexual behaviors in venues where men reported meeting sexual partners, based on their level of compulsivity. Venues that could be characterized as "sexualized" were better predictors of higher sexual compulsivity scores among men than those that are "social" in nature. Men who were higher in compulsivity reported patterns of saturating sexualized venues in order to find sexual partners. Given the unique patterns of sexual partner-seeking in this area, interventions to decrease sexual risk-taking should take into account that men who have a higher propensity for sexual compulsivity are visiting multiple venues, and prevention messages need to be tailored to be consistent across these contexts. In addition, these may need to be differentially designed based on the specific environment in which they are to be delivered.  相似文献   
88.
目的探讨PDCA循环法在临床用血申请审核审批过程中的应用及效果。方法应用PDCA循环法对临床用血申请审核审批进行质量持续改进,对临床用血申请审核审批不合格及未用血后疗效评估申请进行原因分析,制订相应的措施、持续改进计划。结果通过PDCA循环,临床用血申请的审核审批率由干预前的82.7%提高至99.2%,审核审批率明显提高;疗效评估率由2012年的90.3%上升至2013年的97.7%。结论采用PDCA循环能有效提高临床用血申请审核审批率和输血后疗效评估率,持续改进临床输血质量管理,促进临床科学、合理、有效用血。  相似文献   
89.
背景 急性缺血性脑卒中(AIS)是成年人死亡和致残的主要原因之一,如何恢复是全世界的一个主要健康问题。尽管在有效预防和治疗方面取得了相当大的进展,但仍面临着重大挑战,特别是急诊处理,静脉溶栓治疗是唯一一种改善患者预后的方法,但只有少数患者能使用。目的 探讨优化静脉溶栓流程对AIS患者入院至静脉溶栓用药时间(DNT)的影响及对高级卒中中心建设的作用。方法 收集2015年11月-2018年11月海宁市人民医院收治的采用重组组织型纤溶酶原激活物(rt-PA)静脉溶栓治疗的AIS患者186例为研究对象,根据时间进行分组,2015年11月-2018年3月患者采用常规溶栓流程为常规组,2018年4-11月患者接受优化静脉溶栓流程为优化组。比较两组患者一般资料、发病至就诊时间(OTD)、入院至CT检查时间(DTI)、入院至化验检验时间(DTL)、DNT、溶栓距发病时间(TP_WINDOW)、症状性脑出血(sICH)发生率,入院时、溶栓24 h及出院时评价美国国立卫生研究院卒中量表(NIHSS)评分,以ΔNIHSS评分≥4分为有效,出院后3个月临床结局采用改良Rankin量表(mRS)评定。结果 优化组入院时NIHSS评分低于常规组(P<0.05)。常规组与优化组患者OTD、sICH发生率、有效率、出院时NIHSS评分比较,差异均无统计学意义(P>0.05);优化组患者DTI、DTL、DNT、TP_WINDOW、出院后3个月mRS评分低于常规组,DNT<60 min所占比例高于常规组(P<0.05)。结论 优化静脉溶栓流程可以有效缩短AIS患者DNT,并有助于DNT达标控制在60 min内,未增加溶栓出血风险且影响远期预后,值得推广。  相似文献   
90.
通过系统梳理涉及伦理委员会建设的现行立法,从法律角度探讨伦理委员会的法律地位、人员组成、资质考核、操作规程、法律监督等方面存在的问题。通过剖析存在的问题,建议提高立法等级,确定性别比例和专业占比标准,参考美国伦理委员会专业认证制度加强委员资质考核;建立专门操作指南,强调跟踪审查;适当调整各方监管权限,下设专门监管机构。  相似文献   
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