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71.
用PCR—RFLP和16SrDNA指纹图法分析幽门螺杆菌基因型 总被引:1,自引:1,他引:0
本文建立了PCR-RFLP和16srDNA指纹图法.对19株幽门螺杆菌(HP)进行基因型分析:HP尿素酶C基因的PCR扩增产物.分别用HindⅢ、HaeⅢ、AluⅠ酶切,结果显示:每个酶均将19株HP分为3种RFLP图谱.综合HindⅢ,HaeⅢ和AluⅠ酶切结果,19株HP分为10个酶切带型;PCR扩增HP标准株16SrRNA基因,地高辛标记制备550bp探针,19株HPDNA分别经HaeⅢ和EcoRⅠ酶切、电泳后,通过Southern杂交获16SrDNA指纹图,结果显示:HaeⅢ酶切分为14个杂交带型,EcoRⅠ酶切19株HP杂交带型均不同。本实验表明:上述两种方法重复性好,分群力高,可准确有效地对HP作出鉴定并将其分型。19株HP株间存在基因型差异。 相似文献
72.
目的:构建含有目的基因kring5的真核植物细胞穿酸表达载体。方法:应用RT-PCR方法,从正常人肝脏组织中获得kringle5基因,测序后,再通过DNA重组技术,将kringle5基因片段克隆到真核植物细胞表达载体pBI121和pCAMBIA3301上。结果:得到的kringle5基因序列测定结果与文献相符,重组载体pB1k5和pC33k5经酶切鉴定正确,含有植物高效表达CaMV35S启动子。结论:重组载体pB1k5和pC33k5不仅可以在大肠杆菌中稳定复制,而且可以在植物细胞中表达。 相似文献
73.
74.
M Ochsner 《European journal of medicinal chemistry》1996,31(12):939-950
Zinc(II) phthalocyanine is the active component of the liposomal formulation CGP 55847 which showed a high activity in photodynamic therapy in a variety of animal tumours. The photophysical properties of zinc(II) phthalocyanine have been studied in detail and compared to those of Photofrin, the only sensitizing agent approved so far for phase III/IV clinical trials. Since the efficacy of photodynamic therapy intrinsically depends on the spectroscopic features of the sensitizer, quantum chemical methods have proven to be an efficient means for optimizing chemical structures. As will be shown, a simple modification of the time-honoured INDO model of Pople allows a prediction of the singlet and triplet state properties of molecules of the size of zinc(II) phthalocyanine with an rms error of ≤ 1000 cm−1. 相似文献
75.
H. W. Chu S. Balzar J. Y. Westcott J. B. Trudeau Y. Sun D. J. Conrad S. E. Wenzel 《Clinical and experimental allergy》2002,32(11):1558-1565
BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels. 相似文献
76.
异氟醚控制性降压对颅内动脉瘤夹闭术血中S100B含量的影响 总被引:3,自引:1,他引:2
目的 测定颅内动脉瘤夹闭前后血中S1 0 0B蛋白含量 ,研究异氟醚控制性降压对脑功能的影响。方法 择期颅内动脉瘤夹闭术病人 30例 ,ASAⅠ~Ⅱ级 ,随机分为两组 :异氟醚降压组 (n=1 5 )和异氟醚非降压组 (n =1 5 )。非降压组术中吸入 1MAC异氟醚维持麻醉。降压组行异氟醚控制性降压 ,平均动脉压下降幅度 30 %~ 4 0 % ,夹闭动脉瘤后降低异氟醚吸入浓度 ,终止降压。分别于切皮前、动脉瘤夹闭后即刻、2、4h、术后第 1、2天取血测定S1 0 0B蛋白含量 ,并于术后 1周随访病人 ,记录有无术后神经系统并发症。结果 (1 )异氟醚降压后 30min平均动脉压由诱导前的 (95 2± 1 2 3)mmHg降至 (5 8 8± 5 4 )mmHg ,停止降压后 30min血压回升至 (75 1± 8 3)mmHg。降压后外周血管阻力及心肌收缩加速度下降 ,但心率及心输出量均无显著性变化 ;(2 )异氟醚降压组与非降压组间同一时间点血中S1 0 0B蛋白浓度无明显差异。降压组术后第 1天及第 2天血中S1 0 0B蛋白浓度均显著升高 (F =2 94 4 ,P =0 0 1 8)。结论 在颅内动脉瘤夹闭术中应用异氟醚控制性降压可能加重了术后脑损伤 ,不利于病人围麻醉期脑功能的保护 相似文献
77.
78.
给出了用“混合型”雅可比级数的泰勒平均逼近黎普希兹函数类的点态估计。 相似文献
79.
新螯合剂对铍中毒的解毒和促排效果 总被引:2,自引:0,他引:2
本文报道了新蟹合剂8102,S186对铍中毒动物的解毒和促排作用,并与811,DTPA 进行比较,大、小鼠BeSO_4中毒后,给予不同剂量的螯合剂解毒,结果表明,8102,S186对铍中毒动物的解毒效果均优于后两种,对大鼠的解毒作用8102优于S186,但S186对小鼠的解毒作用优于8102。螫合剂对大鼠BeSO_4染毒的排铍效果实验结果证明:各螫合剂的排铍效果强弱:8102>S186>811>DTPA。8102和S186对大鼠急性铍中毒有明显的排铍效果,若染毒前1h 或延迟4h 给药,仍有显著的排铍作用,但低于即刻用药组的效果。8102对亚急性染毒带铍状态亦有较高促排铍的作用。 相似文献
80.
Triploid origin of the gibel carp as revealed by 5S rDNA localization and chromosome painting 总被引:2,自引:0,他引:2
5S ribosomal DNA (rDNA) was isolated and sequenced from the gibel carp Carassius auratus gibelio with 162 chromosomes and crucian carp Carassius auratus with 100 chromosomes, and fluorescent probes for chromosome localization were prepared to ascertain the ploidy origin and
evolutionary relationship between the two species. Using fluorescence in-situ hybridization (FISH), major 5S rDNA signals were localized to the short arms of three subtelocentric chromosomes in the gibel
carp and to the short arms of two subtelocentrics in the crucian carp. In addition, some minor signals were detected on other
chromosomes of both species. Simultaneously, six chromosomes were microdissected from the gibel carp metaphase spreads using
glass needles, and the isolated chromosomes were amplified in vitro by degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR). Significantly, when the DOP-PCR-generated probes
prepared from each single chromosome were hybridized, three same-sized chromosomes were painted in each gibel carp metaphase,
whereas only two painted chromosomes were observed in each crucian carp metaphase spread. The data indicate that gibel carp
is of triploid origin in comparison with diploid crucian carp. 相似文献