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41.
卡介苗(BCG)是全球应用最广泛的疫苗,也是一种能携带多种致病菌保护性抗原表达的疫苗载体。本研究以pUC19为骨架,分别克隆入BCG分泌抗原85-B的调节和信号肽序列、Neo基因序列(编码卡那霉素抗性)以及分枝杆菌质粒复制基因,构建成分枝杆菌-大肠杆菌穿梭质粒pBCG-8000。该重组质粒在分枝杆菌(含BCG)、大肠杆菌两个系统中均能稳定复制,并能稳定表达卡那霉素抗性。本研究为把BCG和其它分枝杆菌发展成为多价疫苗载体打下了基础。 相似文献
42.
论述目前我国航空心理学研究中的五个问题:(1)我军飞行人员心理选拔;(2)飞行能力和空间定向;(3)应激对飞行工作的影响及其应付方法;(4)军事飞行员心身疾病;(5)飞行员临时停飞和心理学评估研究。建议在航空心理学的科学研究中,将心理学与医学及其它学科相结合进行研究。 相似文献
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44.
HY Chan XQ Yao SY Tsang BP Bourreau FL Chan Y Huang . 《Journal of cardiac surgery》2002,17(6):562-562
Background: Calcitonin gene-related peptide (CGRP) is known to have an extremely potent and prolonged vasodilator effect on the coronary arteries. Studies have shown that CGRP increased coronary blood flow and alleviated reperfusion injury in vitro. It is still unknown, however, whether exogenous CGRP has a protective effect on the reperfusion heart associated with cardiopulmonary bypass (CPB). Methods: An in vivo porcine model of CPB was established. Twenty pigs, 10 controls and 10 CGRP used animals (CGRP group), were performed a median sternotomy followed by a standard CPB. All the hearts were arrested for 45 minutes. In the CGRP group, 1mg/kg CGRP was added into the cardioplegia, and another 1mg/kg was reperfused just before the aortic cross-clamp was removed. In both groups, myocardial microvascular perfusion, coronary arterial microvessel diameter and microvessel blood flow were detected by a laser doppler flowmeter and a contact microscope with TV monitor on five consecutive time perioperatively. Result: Myocardial microvascular perfusion was significantly higher and coronary arterial microvessel diameter was larger in the CGRP group on every point of time of reperfusion compared to those in the control group. In the CGRP group, microvessel blood flow also improved significantly than that in the control group during reperfusion. Conclusion: CGRP improves myocardial microcirculation during cardiac ischemia-reperfusion associated with CPB and could become a new, potent myocardial protector. 相似文献
45.
Arthroscopic single-bundle posterior cruciate ligament reconstruction: Retrospective review of 4- versus 7-strand hamstring tendon graft 总被引:1,自引:0,他引:1
Various methods of posterior cruciate ligament (PCL) reconstruction have been reported. However the results have been unpredictable. This paper reports a retrospective comparative study of single-bundle PCL reconstruction comparing 22 patients who underwent 7-strand hamstring graft (7SHG) against 21 patients who had a 4-strand hamstring graft (4SHG). All had an isolated chronic PCL rupture. Suspension fixation was performed on both the femoral and tibial ends. The minimum follow-up time was 2 years. The outcome measures used were the International Knee Documentation Committee, Lysholm, and Tegner rating scales. Stability was improved in the 7SHG group when compared with the 4SHG group, with an average posterior laxity of 1.7 mm compared to 3.7 mm. The Lysholm and Tegner scores were also significantly improved. In reconstruction for isolated chronic PCL rupture using a single-bundle technique, 7SHG gave better results than 4SHG. 相似文献
46.
Heping Huangfu Wenbo Xu Hongkui Wang Qing Dong Hongwei Guo Yanting Sun 《Avian pathology》2018,47(3):245-252
To better understand the prevalence of Gallibacterium anatis in different poultry species, a rapid and accurate method was developed to detect G. anatis using a TaqMan fluorescent quantitative polymerase chain reaction (qPCR). Specific primers and a TaqMan probe were designed based on the reference gtxA gene sequence. The qPCR standard curve showed a good linear relationship, and the method showed good reproducibility, sensitivity, and specificity, indicating its suitability for G. anatis identification and quantitative analysis. A comparison of the detection results in 160 clinical swab samples showed that the detection rate (54.4%) of the qPCR for G. anatis was better than that of two conventional methods: gyrB gene-based qPCR for G. anatis (51.9%) and culture-based identification (34.4%). G. anatis was detected in layer chicken (77.3%), Silkie chicken (72.7%), and duck (27.1%) with relatively high detection rates, whereas dove (8.8%) and quail (3.0%) showed lower detection rates, indicating the different prevalence of G. anatis in different fowl species. 相似文献
47.
目的:一氧化氮在维持机体多个系统的生理功能中起重要作用,许多慢性疾病可造成一氧化氮产生减少,此时一氧化氮供体是一种必要的补充。观察一氧化氮外源性供体L-arginine对体外培养破骨细胞增殖及骨吸收功能的影响。方法:实验于2005-06/2006-05在四川大学华西医院生物治疗国家重点实验室干细胞与组织工程研究室完成。选择出生1d的清洁级SD大鼠乳鼠,采用骨髓诱导法体外培养破骨细胞,培养液内分别加入0.3,0.6,1.0g/L不同浓度的L-arginine,并以等体积三蒸水作为对照。培养7d后,以抗酒石酸酸性磷酸酶染色观察破骨细胞数目、形态,MIAS-2000图像分析仪检测骨片上骨吸收陷窝的数目和面积,并用扫描电镜观察不同浓度L-arginine对骨吸收陷窝的影响。结果:①破骨细胞的一般形态:破骨细胞较其他细胞大,形态不规则,呈油煎蛋形、长条形、腊肠形或漏斗形等,细胞内可见几个至几十个核不等。抗酒石酸酸性磷酸酶染色酶活性部分酒红色,颗粒状。②抗酒石酸酸性磷酸酶阳性细胞数:各组破骨细胞数目随着L-arginine浓度增加而减少(P<0.05)。③骨吸收陷窝的面积和数目:骨片培养7d,吸收陷窝计数的结果显示,0.3g/L以上浓度L-arginine对破骨细胞吸收功能均有明显抑制作用,并呈剂量相关性。0.3g/LL-arginine组陷窝面积为对照组的91%(P<0.05),0.6g/LL-arginine组为对照组的80%(P<0.05),1.0g/LL-arginine组为对照组的69%(P<0.01)。结论:采用骨髓诱导法培养的破骨细胞数量多、纯度高,且具有明显的骨吸收功能。L-arginine抑制破骨细胞增殖,抑制破骨细胞骨吸收功能,并呈剂量相关性。 相似文献
48.
Yao GB Fu XX Tian GS Xu DZ Hao LJ Huangfu YS Su CX 《Journal of gastroenterology and hepatology》2000,15(10):1165-1170
49.
Jack XQ Pang Erin Ross Meredith A Borman Scott Zimmer Gilaad G Kaplan Steven J Heitman Mark G Swain Kelly Burak Hude Quan Robert P Myers 《Journal canadien de gastroenterologie》2015,29(3):131-138