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101.
高效液相色谱仪测定未结合胆红素光异构体校正因子及临床意义 总被引:2,自引:0,他引:2
目的分析不稳定、无法提纯的未结合胆红素(4Z,15Z-胆红素Ⅸα,简称ZZ)光异构体的校正因子,以便临床对它们进行定量分析研究.方法采用高效液相色谱对光照前后ZZ光异构体峰面积进行测定,然后通过公式计算校正因子.结果两种主要的光异构体的校正因子分别是4Z,15E-胆红素Ⅸα为1.33±0.01,光红素为1.85±0.02.结论校正因子为临床定量分析ZZ光异构体提供客观依据. 相似文献
102.
Aim To study
the effect of nitric oxide (NO) on LoVo cells after hyperthermia combined with MMC and
their mechanisms. Methods The levels of NO were determined in cell culture medium of LoVo
cells by Cu-Cd reduction method.Results The levels of NO in control (45.9±16.12) μmol/L
group were lower than those in chemohyperthermy(92.3±24.30) μmol/L and hyperthermia
(67.67±15.48)μmol/L group (P<0.01,P<0.05 respectively). Levels of NO in
chemohyperthermy and hyperthermia groups were higher than those in chemotherapy(47.03±16.32)μmol/L(P<0.01,P<0.05
respcevtively). The levels of NO in chemo-hyperthermy group were higher than those in
hyperthermia group(P<0.05), and those in chemotherapy group higher than in control
group but without statistical significance.Conclusion Chemohyperthermy and hyperthermia
could remarkably enhance the levels of NO produced by LoVo cells. NO levels could also be
enhanced by chemotherapy. It could be concluded that Nitric Oxide Synthase (NOS) in tumor
cells might be activated by hyperthermia, chemohyperthermy and chemotherapy, and increased
NO level which induced cytotoxic reaction. This may be one of the mechanisms of treatment
with chemohyperthermy. 相似文献
103.
用溶剂蒸发法制备了以新型生物可降解材料聚羟基丁酸酯为载体、以安定为模药的缓释微球,讨论了药物与载体之比对药物含量与包封率的影响,以及制备微球条件对药物释放性能的影响;微球平均粒径为30~40μm,粒径分布在1~1.5之间,最大载药量为19.51%;最高包封率为67.11%;体外累积释放曲线呈“两相”释放特征并拌随初始的“突释效应”。扫描电镜观察微球表面呈皱缩表观形态结构,微球内部横断面具有孔道与孔 相似文献
104.
Objective To evaluate the ability of the RIFLE classification to predict hospital mortality in adult patients who underwent cardiac surgery. Methods From October Ist 2006 to December 31st 2006, five hundred and nine adult patients who underwent coronary artery bypass grafting and/or valve operation were enrolled in this study. Renal function was assessed daily according to the RIFLE classification, meanwhile, APACHE Ⅱ score and SOFA score were also evaluated, as well as the maximum scores were recorded. Results Mean duration of ventilation support was 18(14 - 19) hours, the time of ICU stay was 1.4 ± 1.0 days, and the time of postoperative hospital stay was 12. 0(10.0- 15.0) days. 167 patients (32. 8%) incurred postoperative ARF according to the RIFLE classification. The overall mortality was 4. 3% (22/502). A significant increase (P < 0. 01) was observed for mortality based on RIFLE classification. By applying the area under the receiver operating characteristic curve, the RIFLE classification had more powerful discrimination power [0. 933, (95% CI 0. 872 -0. 995) ,P <0. 001]. Conclusions ARF is one of the major complications in postcardiotomy patients. Analytical data suggested the good discriminative power of the RIFLE classification for predicting inpatient mortality of adult postoperative patient with ARF, and the RIFLE classification is simple and practically performed. According to the RIFLE classification, patients with RIFLE class I or class F incur a significantly increased risk of in-hospital mortality compared with those who never develop ARF. 相似文献
105.
目的 体表心电图QT离散度(QTd)增大在冠心病患者是预测室性心律失常事件的有用指标。旨在估价冠心病患者经皮冠状动脉腔内成形主支架术(PTCA+stent)前后对QT离散度的影响。方法 对60例冠心病患者行PTCA+stent术前后QT离散度进行分析。男性46例,女性14例,平均年龄57岁,患者为单支血管病变36例,多支血管病24例。本组对PTCA+stent术前后同步3导联的标准12导联心电图Q 相似文献
106.
目的 探讨心脏停搏液 p H值对离体未成熟大鼠心肌的影响 .方法 采用 SD幼鼠 (18~ 2 1d)离体工作心模型 ,14℃低温缺血 12 0 min,缺血前分别以 p H为 6 .40 ,7.0 0 ,7.2 5 ,7.40 ,7.80和 8.2 0的 St.Thomas' 液单次灌注 ,观察记录缺血前后心功能的变化及心肌 CPK漏出量 .结果 1缺血再灌注 30 m in后主动脉流量恢复百分比依次为 (6 2±5 ) % ,(72± 4) % ,(83± 4) % ,(78± 3) % ,(70± 3) %和 (5 8±4) % ,以 p H 7.2 5组保护效果最好 .2心肌 CPK漏出量各组间无显著差异 .结论 p H值为 7.2 5的弱酸性心脏停搏液对大鼠未成熟心肌可提供良好的保护作用 ,同时大鼠未成熟心肌可耐受较大范围的 p H变化 . 相似文献
107.
七氟醚和异氟醚心血管效应的比较 总被引:11,自引:0,他引:11
目的 比较不同浓度七氟醚和异氟醚的心血管效应 .方法 2 0只健康杂种犬随机分为七氟醚组和异氟醚组 .监测有创动脉压 ;经大静脉置入漂浮导管测定肺动脉楔压、中心静脉压、心输出量 .吸入麻醉药 (七氟醚或异氟醚 ) ,维持其呼气末浓度在 14.5 m L· L- 1 或 8.5 m L· L- 1 ,10 min后测定上述参数值 .结果 七氟醚和异氟醚 :1对心率均没有显著影响 ;2均可呈剂量依赖性地降低体循环血压和血管阻力 ,对心功能也有剂量依赖性的抑制作用 ,两药之间的差异没有显著性 ;3七氟醚降低肺动脉压的作用强于异氟醚 ,但与浓度大小无明显关系 .结论 七氟醚和异氟醚具有相似的心血管效应 ,除七氟醚降低肺动脉压的作用强于异氟醚外 ,二药对心血管系统功能均有剂量依赖性的抑制作用 . 相似文献
108.
采用局部注射 ,针刀松解 ,手法剥离 ,中药调理 4步法有机结合治疗肩周炎 2 0 8例 ,结果治愈 187例 ,显效 13例 ,优良率 96.3 %。认为针对局部病变及肩部整体功能调理 ,是获得较好疗效的关键。 相似文献
109.
Antigenic heterogeneity of the hepatitis C virus NS4 protein as modeled with synthetic peptides 总被引:1,自引:0,他引:1
The effect of sequence heterogeneity on the immunologic properties of two strong antigenic regions of the hepatitis C virus (HCV) NS4 protein was studied by using a set of 443 overlapping 20-mer synthetic peptides. One antigenic region comprising the cleavage site between NS4a and NS4b (region 5-1-1) was modeled with peptides derived from 73 different known sequences, representing HCV genotypes 1-6. The other antigenic region, designated region 59 and located at the C-terminus of the NS4b protein, was modeled with peptides from 7 known sequences representing genotypes 1-3. All peptides were tested for antigenic reactivity by enzyme immunoassay with a panel of anti-HCV-positive serum specimens representing genotypes 1-5. The data demonstrated that immunoreactive peptides fell into two groups. One group, represented by N-terminal peptides, demonstrated genotype-independent immunoreactivity; the other group, from the central part of region 5-1-1, showed strict genotype specificity. Nineteen peptides from the genotype-independent group strongly immunoreacted with a wide range of serum samples containing antibodies to all 5 HCV genotypes. Twenty-five peptides from the genotype-specific group were found to strongly react with serum containing antibodies only to the genotype from which the peptides were derived. Similar to the N-terminal part of region 5-1-1, peptides derived from region 59 did not show genotype-specific immunoreactivity. Some peptides derived from the central part of region 59 showed very strong and broad antigenic reactivity. Thus, after examining two antigenic regions of the NS4 protein, we identified short sequences that can be used for the efficient detection of either genotype-independent or genotype-specific HCV antibodies. 相似文献
110.
高效毛细管电泳柱上富集测定福莫特罗干糖浆 总被引:1,自引:0,他引:1
研究了低规格药物福莫特罗干糖浆的含量测定。方法采用高效毛细管电泳柱上富集的方法则定。电压进样,10KV,20s,运行电压20KV,运行缓冲液为80mmol.L^-1磷酸盐缓冲液;检测波长为200nm。结论本法简便,准确,重现性,样口柱上富集260倍。 相似文献