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11.
The purpose of this study was to determine the outcome of patients with metastatic breast cancer treated with high-dose busulfan (Bu), melphalan (Mel) and thiotepa (TT) followed by peripheral blood stem cell (PBSC) infusion. Fifty-one patients with chemotherapy refractory (n = 32) or responsive (n = 19) metastatic breast cancer received Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC collected after chemotherapy and growth factor (n = 43) or growth factor alone (n = 8). The 100 day treatment-related mortality was 8% including one death from cytomegalovirus pneumonia, one from aspiration pneumonia and two from regimen-related toxicity (RRT). Seven of 28 refractory (25%) and 5/7 (71%) responsive patients with evaluable disease achieved a complete response of all measurable disease or all soft tissue disease with at least improvement in bone lesions (PR*). Fifteen of 51 patients (29%) are alive and progression-free a median of 423 days (range 353-934) after treatment, 5/32 (16%) with refractory disease and 10/19 (53%) with responsive disease. The probabilities of progression-free survival (PFS) at 1.5 years for the patients with refractory (n = 32) and responsive (n = 19) disease were 0.24 and 0.53, respectively. These preliminary data suggest that high-dose Bu/Mel/TT has significant activity in patients with advanced breast cancer and may be superior to some previously published regimens.  相似文献   
12.
机械合金化的原理及在磁性材料研究中的应用   总被引:14,自引:0,他引:14  
居毅  李宗权 《功能材料》2002,33(1):12-14,18
介绍了机械合金化的原理和描述机械合金化过程的理论模型。综述了机械合金化在磁性材料研究中的应用,并对目前研究中的存在的问题及发展前景进行了分析。  相似文献   
13.
Objective: Guided by the extended parallel process model (EPPM), the objective was to assess control processes dominant in influenza behavior decisions. Design: Cross-sectional survey. Results: Response rate was 31% (n=968). Regarding influenza risk, 59% were in danger control. Those in fear control were more likely to report influenza infection (p=.000). In the nonvaccinated, those in fear control were more likely to indicate not knowing where to get the vaccine (p=.016) and that it was unavailable (p=.027), and those in danger control believed they did not need it (p=.023). Zero critical values were more likely to indicate that no health provider recommended the shot (p=.002). Conclusions: Most perceived efficacy to be stronger than threat related to influenza; according to the EPPM, they are aware of their risk but recognize their ability to avert it. For those in danger control, messages should focus on increasing perceptions of severity and susceptibility to positively affect behavior change. For those in fear control, messages should focus on efficacy only. With a critical value of zero, no threat is induced, and a high-threat/high-efficacy approach should be taken. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
王政富  鞠泳 《山西建筑》2003,29(11):32-33
阐述了时空效应规律在软土深基坑工程中的运用情况,实践证明,运用时空效应规律,能可靠而合理地利用土体自身在基坑开挖过程中控制土体位移的潜力而达到保护环境的目的。  相似文献   
15.
高频微型脉冲管制冷机的实用化研究   总被引:2,自引:0,他引:2  
脉冲管制冷机经过多年的发展,性能不断改善,目前已开始进入实用化阶段。高频微型脉冲管制冷机结构紧凑,应用方便,并且主要工作在需求量较大的液氮温区,因此将首先得到一定规模的应用。介绍了作者针对脉冲管制冷机在红外和超导方面的应用所作的实用化工作,讨论了尚待解决的问题。  相似文献   
16.
文章介绍了埋地管道三层PE外覆盖层系统的构造参数和性能特点,论述了两种用于埋地钢质管道外覆盖层状况检测的方法,一种是多频管中电流法,另一种是DCVG/CIPS组合检测技术。分别介绍了两种方法的工作原理、操作方法和设备,并结合工程实例进行了说明。这些方法和设备可分别或同时用于管道不开挖检测防腐层破损点的位置以及漏点大小。  相似文献   
17.
柴油机针阀体的乙炔低压渗碳   总被引:2,自引:0,他引:2  
乙炔低压渗碳可以有效地避免在真空渗碳过程中产生炭黑和焦油,同时由于乙炔具有较高的供碳能力,使这一技术尤其适用于针阀体这样的小直径深盲孔零件。  相似文献   
18.
Active transport of nitrofurantoin across the mammary epithelium in vivo   总被引:1,自引:0,他引:1  
Nitrofurantoin is a commonly used urinary tract antibiotic that has been found at high concentrations in human milk. In vivo studies in rats were carried out to determine the mechanism by which this drug crosses the mammary epithelium. Lactating rats were gavage-fed with nitrofurantoin, and their milk and plasma levels of the antibiotic were measured at intervals up to 8 hr. The average milk-to-plasma (M/P) ratio, calculated from the areas under the milk and plasma curves, respectively, was 23 compared with a ratio predicted to be about 0.3 on the basis of lipid partitioning and protein binding determinations. M/P ratios for two nitrofurantoin congeners were also calculated. The neutral compound furazolidone had a M/P ratio of about 1, as predicted, whereas the basic compound furaltadone had a M/P ratio of 3.49 compared with a predicted ratio of 1.4. These data suggest that nitrofurantoin and, to a lesser extent, furaltadone are actively transported across the mammary epithelium into milk.  相似文献   
19.
20.
A survey of 45 transmembrane (TM) helices and 88 helix packing interactions in three independent transmembrane protein structures reveals the following features. (1) Helix lengths range from 14 to 36 residues with an average length of 26.4 residues. There is a preference for lengths greater than 20 residues. (2) The helices are tilted with respect to the bilayer normal by an average of 21 degrees, but there is a decided preference for smaller tilt angles. (3) The distribution of helix packing angles is very different than for soluble proteins. The most common packing angles for TM helices are centered around +20 degrees while for soluble proteins packing angles of around -35 degrees are the most prevalent. (4) The average distance of closest approach is 9.6 A, which is the same as soluble proteins. (5) There is no preference for the positioning of the point of closest approach along the length of the helices. (6) It is almost a rule that TM helices pack against neighbors in the sequence. Of the 37 helices that have a sequence neighbor, 36 of them are in significant contact with a neighbor. (7) An antiparallel orientation is more prevalent than a parallel orientation and antiparallel interactions are more intimate on average. The general features of helix bundle membrane protein architecture described in this survey should prove useful in the modeling of helix bundle transmembrane proteins.  相似文献   
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