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101.
目的 了解α干扰素(IFN—α)在移植前使用对慢性粒细胞白血病(CML)患者非亲缘异基因骨髓移植(URD—BMT)预后的影响。方法 分析总结行URD—BMT的CML第1次慢性期(CP1)患者53例,其中BMT前未用IFN—α治疗组23例,用IFN—α治疗组30例;其中疗程≤12个月22例,〉12个月8例。采用单因素分析和Cox比例风险模型分析移植前使用IFN—α对CML患者URD—BMT后植入效果、急性移植物抗宿主病(GVHD)发生及患者5年存活率的影响。结果 经Cox模型多元回归分析,患者年龄、性别、确诊至URD—BMT的时间、停IFN—α距URD—BMT时间对生存率无影响;各组的总生存率、无病生存率、非复发死亡率、植活率、复发率、植入失败率、急性GVHD和慢性GVHD发生率差异均无统计学意义均(P〉0.05)。结论 本文资料所列条件下,移植前使用IFN—α不会对URD—BMT产生不利影响。  相似文献   
102.
树脂加强型玻璃离子黏结剂黏结力的实验研究   总被引:3,自引:0,他引:3  
目的 了解光固化树脂加强型玻璃离子水门汀的剪切强度能否满足临床需要;并比较不同条件下其剪切强度的变化.方法 收集离体前磨牙50颗,随机均分为5组.第1组(对照组):35%磷酸酸蚀30s,冲洗、干燥,涂黏结剂,采用京津釉质黏结剂黏结托槽.第2、4组:35%磷酸酸蚀30s,冲洗,湿润,采用光固化型的Fuji Ortho Lc树脂加强型玻璃离子黏结托槽.第3、5组:不酸蚀,采用光固化型的Fuji Ortho Lc树脂加强型玻璃离子黏结托槽.1、2、3组用电子万能实验机测24h的抗剪切强度,4、5组测30 min的抗剪切强度.并统计牙面上的黏结剂残留量.结果 第2、3、4组的抗剪切强度均能满足临床需要,第5组的抗剪切强度不能满足临床需要,第2组的抗剪切强度与其它各组相比差别有显著性.结论 光固化树脂加强型玻璃离子在酸蚀和免酸蚀后24h,以及酸蚀黏结30min后的剪切强度均能满足临床需要;而免酸蚀黏结30min的抗剪切强度不能满足临床需要;酸蚀后光固化树脂加强型玻璃离子的剪切强度明显增强.  相似文献   
103.
The purpose of this work was to study the possibility of neutralizing high-calcium fly ash expansion during hydration. The object of the study was the fly ash of Berezovskaya GRES, which is capable of independent setting and hardening. The test in the Le Chatelier molds showed that the divergence of indicator arms was 90–100 mm 1 day after mixing with water. The expansion and cracking of the fly ash could be completely prevented by silica fume addition in an amount of 42.9% by weight of the fly ash. At the same time, the compressive strength of specimens from the fly ash–sand paste in a ratio of 1:5 at the age of 28 days was 1.47 MPa. The isothermal heat release at a temperature of 20 °C for 10 days reached 500 kJ/kg. XRF and DTA results showed that free lime in the fly ash was completely hydrated in 11 days and gave the greatest expansion in the absence of silica fume. The presence of silica fume made the lime hydration incomplete and decreased the expansion. Unslaked free lime remained in the system. Exothermic data showed that silica fume inhibited CaO hydration from the reaction start.  相似文献   
104.
不同粘结剂对瓷-牙本质粘结剪切强度的研究   总被引:1,自引:0,他引:1  
目的:观察比较不同树脂粘结剂对IPS Empress 2全瓷基底粘结剪切强度的效果。方法:选择无龋坏的人磨牙24个,随机分为4组,每组6个。第1组用RelyX Veneer进行粘结。第2组用RelyX unicem进行粘结。第3组用RelyX ARC进行粘结。第4组用Variolink 2进行粘结。所有样本在37°C蒸馏水中储存24h后,进行测试,记录剪切强度值,用SPSS11.0对结果进行单因素方差分析,并在光学显微镜下观察粘结破坏情况。结果:RelyX Veneer、RelyX ARC、Variolink 2的剪切强度显著高于RelyX unicem的剪切强度(P〈0.05),破坏界面多发生在牙本质与粘结剂之间。结论:RelyX Veneer、RelyX ARC、Variolink 2都可以用于IPS Empress 2全瓷系统的粘结。  相似文献   
105.
In order to determine whether 5-[bis(carboxymethyl) amino]-2-carboxy4-cyano-3-thiopheneacetic acid distrontium salt (S12911-2) inhibits bone resorption by acting on the differentiation and/or function of osteoclasts, its effects were assessed on the 1,25-dihydroxyvitamin D(3)-induced expression of carbonic anhydrase II and vitronectin receptor in chicken bone marrow cells, and on the resorbing activity of authentic rat osteoclasts cultured on bone slices. S12911-2 dose-dependently inhibited, after a 6-day exposure, the expression of carbonic anhydrase II and vitronectin receptor in stimulated osteoclasts (46% and 40%, respectively, at 10(-3) M Sr(2+), P<0.05). A pre-incubation of bone slices with S12911-2 induced a dose-dependent inhibition of bone resorbing activity from 32% at 10(-4) M Sr(2+) to 66% at 10(-3) M Sr(2+) (P<0.05 in each case). A continuous incubation (10(-3) M Sr(2+)) induced a greater inhibition of bone resorbing activity (73%, P<0.05). The inhibition of bone resorption obtained specifically with S12911-2 is related to an inhibition of the differentiation and resorbing activity of the osteoclasts.  相似文献   
106.
目的观察川芎嗪干预BMNCs移植对MCAO小鼠血清TGF-β1的影响。方法采用线栓法制作小鼠MCAO缺血再灌注模型,分离同种系小鼠的骨髓单个核细胞,尾静脉注射BMNCs于造模成功的MCAO小鼠体内,腹腔注射川芎嗪注射液进行干预,以ELISA法测定血清TGF-β1水平。结果川芎嗪干预的BMNCs移植能够使血清TGF-β1值降低更为显著(P〈0.05)。结论川芎嗪干预的BMNCs移植更能促进TGF-β1向脑缝缸局部转移,改善小鼠脑缺血症状。  相似文献   
107.
四种补肾中药对去卵巢大鼠骨质疏松骨形态的作用   总被引:35,自引:0,他引:35  
目的 比较骨碎补、锁阳、淫羊藿和狗脊4种补肾中药对去卵巢(OVX)大鼠骨质疏松的作用。方法 将54只3月龄雌性Wistar大鼠随机分成模型组和中药治疗组。模型组包括非手术组、假手术组和去卵巢组,每组10只;中药组包括骨碎补组、锁阳组、淫羊藿组和狗脊组,每组6只。去卵巢手术后1周,中药组分别用上述4种中药喂养,8周后放血外死全部小鼠,用骨形态主坦学方法比较4种中药对OVX大鼠骨质疏松的防治作用。结果  相似文献   
108.
目的 比较牙体牙髓治疗中常用的骨水泥材料Biodentine与三氧化矿物凝聚体(mineral trioxide ag-gregrate,MTA)在与血液接触条件下的颜色稳定性,并探讨其可能的变色原因.方法 制备直径5 mm、高3 mm的Biodentine和MTA圆盘,将每种材料的24个圆盘随机分配到去离子水组和脱纤...  相似文献   
109.
The crack and carbonation of concrete pose a great challenge to its durability. Therefore, this paper studies the effect of cracks on the carbonation depth of cement paste under different factors. The relationship between carbonation and cracks was determined, and the carbonation mechanism of cement paste with cracks was clarified. The results show that a small water–binder ratio can effectively inhibit the carbonation process. The bidirectional carbonation enlarged the carbonation area around the crack. Within 21 days of the carbonation, the carbonation depth increased with carbonation time, and the Ca(OH)2 on the surface of the specimen was sufficient, allowing for a convenient chemical reaction with CO2. The influence of crack width on the carbonation process at the crack was greater than the influence of the crack depth. Carbonation influenced the hydration of cement-based materials, altering the types and quantities of hydration products. In conclusion, accurately predicting the regularity of carbonation in cracked structures is critical for improving the durability of concrete.  相似文献   
110.
This study aims to develop highly durable, mineral carbonation-based, resource-recycling, secondary cement products based on supercritical carbon dioxide (CO2) curing as part of carbon capture utilization technology that permanently fixes captured CO2. To investigate the basic characteristics of secondary cement products containing concrete sludge waste (CSW) as the main materials after supercritical CO2 curing, the compressive strengths of the paste and mortar (fabricated by using CSW as the main binder), ordinary Portland cement, blast furnace slag powder, and fly ash as admixtures were evaluated to derive the optimal mixture for secondary products. The carbonation curing method that can promote the surface densification (intensive CaCO3 formation) of the hardened body within a short period of time using supercritical CO2 curing was defined as “Lean Carbonation”. The optimal curing conditions were derived by evaluating the compressive strength and durability improvement effects of applying Lean Carbonation to secondary product specimens. As a result of the experiment, for specimens subjected to Lean Carbonation, compressive strength increased by up to 12%, and the carbonation penetration resistance also increased by more than 50%. The optimal conditions for Lean Carbonation used to improve compressive strength and durability were found to be 35 °C, 80 bar, and 1 min.  相似文献   
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