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71.
采用微悬浮聚合制备了聚苯乙烯磁性微球(简称磁球)。在苯乙烯磁流体中加入引发剂和交联剂,然后将此磁流体分散在水中,经过高速剪切乳化,形成较稳定的微悬浮液,然后进行聚合,可合成0.4μm-6μm,主要分布在0.7μm-2.0μm的磁性微球。利用激光粒度分布仪、透射电镜(TEM)以及热重仪(TG)研究了引发剂用量、初始单体用量、聚合温度、磁粉用量、二乙烯苯(DVB)用量等因素对磁球的粒径大小及其分布、凝结量以及磁含量的影响。 相似文献
72.
复发性口腔溃疡与血清TNF-α,TGF-β浓度关系的临床研究 总被引:2,自引:0,他引:2
目的 :研究复发性口腔溃疡与血清TNF α,TGF β浓度关系。方法 :选择复发性口腔溃疡患者 3 2例 ,采用ELISA检测其血清TNF α ,TGF β水平 ,并与正常成年人作对照。结果 :复发性口腔溃疡患者TNF α水平较正常组明显升高 (P <0 .0 1) ,TGF β水平与正常组相比 ,无显著统计学差异 (P >0 .0 5 )。结论 :复发性口腔溃疡的致病过程与细胞因子TNF α有关 ,与TGF β关系不密切 相似文献
73.
为研究叠氮钠对角膜碱烧伤的治疗作用,在家兔的角膜碱烧伤模型中,用1 g/L NaN3及10 g/L NaN3+100g/L枸橼酸钠滴眼剂治疗.同时用硫代巴比妥酸(TBA)反应法检测过氧化脂质(LPO),用组织培养人角膜上皮细胞检测NaN3毒性,发现角膜烧伤后LPO逐渐减少.治疗组病情较轻,且NaN3毒性低,认为角膜碱烧伤后,用NaN3治疗有一定效果. 相似文献
74.
细胞周期蛋白依赖性激酶抑制因子p27^kip1在骨肉瘤中表达的研究 总被引:2,自引:0,他引:2
目的:探讨细胞周期蛋白依赖性激酶抑制因子p27^kip1在骨肉瘤发生中的作用。方法:应用免疫组织化学方法(S-P法)检测27例传统骨肉瘤、4例皮质旁骨肉瘤和12例良性骨肉瘤中p27^kip1的表达,表达程度采用半定量方式判定。结果:骨肉瘤中p27^kip1表达的阳性率为100%,良性骨肿瘤中表达的阳性率为75%,两者间有非常显著性差异(P<0.01)。骨肉瘤不同分化与阳性半定量间无相关性(P>0.05)。结论:p27^kip1蛋白表达与骨肉瘤的发生有关,但与骨肉瘤的分化程度无关。 相似文献
75.
槲皮素、异鼠李素对Cu2+介导极低密度脂蛋白氧化修饰的影响 总被引:2,自引:0,他引:2
目的 观察槲皮素 (Que)及异鼠李素 (Iso)对 Cu2 +介导的极低密度脂蛋白 (VL DL)氧化修饰的影响。方法 采用一次性密度梯度离心法分离人血浆 VL DL,用 Cu2 +进行体外氧化修饰 ,抗氧化组在温育前加入不同浓度的 Que和 Iso。分别检测脂蛋白中丙二醛 (MDA)、维生素 E(Vit E)及超氧化物歧化酶 (SOD)活性。结果 Que和 Iso可明显降低 OX- VL DL 中 MDA含量 ,延缓 OX- VL DL 中 Vit E含量的减少 ;显著提高脂蛋白中 SOD活性。结论 Que和 Iso可显著抑制 Cu2 +诱导的 VL DL 的氧化修饰 ,且二者的作用相近 ,这与其抗自由基氧化活性密切相关。 相似文献
76.
Qiu Zhi Guo Quan-bin Ablikim Zakir Shi Xu-wen Hou Jiang-jiang Chen Chang Hasanjan Mamat Akbarjan Mamat Anwar Abdukadir 《International urology and nephrology》2021,53(10):1969-1976
International Urology and Nephrology - This article analyzed the safety and efficacy of ultrasound-guided mini-percutaneous nephrolithotomy (MPCNL) with low-pressure perfusion for the treatment of... 相似文献
77.
Yi-ting Cai Cheng-liang Xiong Tian-shu Liu Shi-liang Shen Jin-peng Rao Feng Qiu 《Andrologia》2021,53(8):e14144
This study aimed at the efficacy of sequential treatment of bone marrow-derived mesenchymal stem cell secretion for busulfan-treated azoospermia in mice. The conditioned media (CM) was obtained from bone marrow mesenchymal stem cells (MSCs) or 293 cells. Chemically induced azoospermia mice received 200 μl MSC-CM or 293-CM twice a week intravenously for three consecutive weeks. The histological assessment of spermatogenic recovery quantifying the expression of meiosis-associated genes, and Sertoli cell barrier functional factors were assessed. The characteristics of TM4 cells (Sertoli cell line) after pre-incubation of MSC-CM in vitro were also obtained. The MSC-CM group had the most spermatogenic colonies among the three groups (p < .05), but no spermatids were seen. Expressions of the meiosis-associated genes Dazl, Vasa, Miwi, Stra8, CyclinA1, Pgk2 and Scp3 in MSC-CM testis were remarkably higher compared with 293-CM and busulfan groups respectively (p < .05). The levels of Sertoli cell barrier functional factors, for example ICAM-1 and N-cadherin, were significantly increased during MSC-CM treatment (p < .05). Moreover, pre-incubation of MSC-CM particularly accelerated the CD54 (ICAM-1) and CD44 expressions of TM4 cells and promoted cell inherent adhesion. MSC-CM treatment can significantly improve the short-term restoration of spermatogonial structures of chemically induced azoospermia related to facilitating Sertoli cell adhesion integrity. 相似文献
78.
Saqib Masroor Qiong Qiu Mohamad Alghothani Rajesh Gupta George V. Moukarbel 《Journal of cardiac surgery》2021,36(1):398-400
Percutaneous occlusion of the left atrial appendage is increasingly being used as an alternative for stroke prevention in patients with non‐valvular atrial fibrillation at high risk of complications from long term anticoagulation. We describe a case of left atrial appendage perforation during Watchman device implantation requiring emergency repair of the left atrium using sternotomy and cardiopulmonary bypass. Technical considerations for surgical decision making are discussed; in hemodynamically unstable patients as well as those at high risk for embolization. 相似文献
79.
Diana F. Florescu Jonathan A. Seaman Andre C. Kalil Fang Qiu Douglas Bremers Scott G. Westphal 《Transplantation proceedings》2021,53(3):1058-1063
BackgroundAntibody induction immunosuppression is commonly used in kidney transplantation to decrease the risk of early acute rejection. However, infectious complications may arise in patients treated with higher intensity induction immunosuppression. In this study, we compared the rate of opportunistic infections during the 3 years after kidney transplantation in recipients who received either alemtuzumab or basiliximab for induction therapy.MethodsAll renal transplant recipients from our center who received induction with alemtuzumab between 2011 and 2016 were included and matched 1:2 (by age and date of transplant) to renal transplant recipients who received basiliximab. The primary outcome was the rate of opportunistic infections.ResultsTwenty-seven patients received alemtuzumab (mean age = 50.8 years; SD ±12), and 54 received basiliximab (mean age = 50.8 years; SD ±11.8). Infections within 3 years posttransplant were not different between groups: BK viremia (P = .99), BK nephritis (P = .48), cytomegalovirus infection (P = .13), varicella zoster virus (P = .22), and all infections (P = .87). Time to infection (P = .67), patient survival (P = .21), and time to rejection (P = .098) were similar in both groups. There were also no group differences in delayed graft function (P = .76), graft loss (P = .97), or rejection (P = .2).ConclusionThe rate of infection was not significantly increased in recipients receiving lymphocyte-depleting alemtuzumab compared to recipients receiving basiliximab induction therapy, despite receiving similar maintenance immunosuppression. Although the immunologic risks differed between the 2 groups, there was no observable difference in clinical outcomes. 相似文献
80.