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91.
目的探讨医院各区域内空气消毒效果及监测、培养所需时间.方法对3496份消毒后空气采用"平板暴露法”进行监测.第一组848份采样时平板暴露15min、置35C温箱培养48h,第二组2648份采样平板暴露5min、培养24h.结果第一组检测无菌生长率为2.6%、阳性检出率为97.4%、合格率为83.3%;第二组无菌生长率为l7.5%.阳性检出率为82.5%,合格率为88.4%.结论根据尘粒(1~10μ粒径)自然下降规律和所带细菌受损后修复需要时间,我们认为采用"平板暴露法”监测消毒后空气时以暴露15min培养48h为好. 相似文献
92.
(目的)探讨血清胃泌素与大肠癌的关系及其临床意义。(方法)用放免法测定39例行根治术的大肠癌病人空腹血清胃泌素水平。(结果)大肠癌病人血清胃泌素水平明显高于对照组(P<0.05);高分化腺癌组术前血清胃泌素水平显著高于对照组及中、低分化腺癌组(P<0.05),术后其鲁沙素水平明显下降(P<0.05);Dukes’A、B期术前血清胃泌素水平明显高于对照组及Dukes’C期组(P<0.05),Dukes’A期病人根治术后其胃沙素水平较术前明显下降(P<0.05)。(结论)血清胃泌素可能对大肠癌细胞有内分泌促生长作用;血清胃泌素水平测定可作为大肠癌诊断及预后判断的辅助指标,并可为选择大肠癌病人行激素治疗提供参考依据。 相似文献
93.
目的:观察芩栀胶囊对小鼠、大鼠精神神经系统和麻醉犬心血管系统、呼吸系统的影响,探讨其用药安全性。方法:芩栀胶囊灌胃给药,观察给药后小鼠和大鼠的一般行为表现及平衡爬杆实验,考察其对精神神经系统的影响;芩栀胶囊十二指肠给药,在八道生理记录仪上记录给药前后相关指标的变化,考察其对心血管系统及呼吸系统的影响。结果:芩栀胶囊不影响小鼠和大鼠的一般行为表现,姿势、步态正常,无肌颤、流涎、瞳孔异常等变化,在平衡爬杆时间点,大鼠30min内跌落次数〈3次;对麻醉犬呼吸频率、血压、心率等未见影响。结论:一般药理作用研究表明,芩栀胶囊对动物精神神经系统、心血管系统及呼吸系统无明显影响,提示其不良反应小。 相似文献
94.
目的研究中药复方治疗糖尿病肾病的疗效及作用机理.方法选非胰岛素依赖型糖尿病(NIDDM),尿蛋白排泄率(UAER):20~200μg/min123例,分3组进行治疗,疗程8周.观察治疗前后空腹血糖、UAER、血压、内皮素含量等.结果治疗后中药组空腹血糖、血压、UAER、血浆TXB2及内皮素含量显著下降,与西药对照组比较无显著差别.结论该中药复方能保护早期糖尿病肾病患者肾功能,其作用可能与改善血管内皮功能有关. 相似文献
95.
目的探讨caspase-3的活化在银杏叶提取物EGb761对肿瘤坏死因子-α(TNF-α)诱导HeLa细胞凋亡中的影响.方法采用流式细胞术检测细胞凋亡,Western blot检测caspase-3 p20活性片段,Caspase-3 Colorimetric Assay试剂盒测定caspase-3活性.结果流式细胞术分析结果显示,EGb761在10~40 mg/L终浓度范围内对重组人肿瘤坏死因子-α(rhTNF-α)诱导的HeLa细胞凋亡均有显著的抑制作用(P<0.01),呈剂量依赖关系;Western blot检测显示,rhTNF-α诱导的HeLa细胞caspase-3 p20活性片段水平增高,能被不同剂量EGb761(10~40 mg/L)明显抑制,且随EGb761浓度增加抑制效果增强;caspase-3活性测定结果显示,EGb761对rhTNF-α诱导的caspase-3活化有显著的抑制作用,且随剂量增加抑制作用增强.结论结果提示,EGb761抑制TNF-α诱导的HeLa细胞凋亡可能与其抑制caspase-3活化有关. 相似文献
96.
Teresa Pekol J Scott Daniels Jason Labutti Ian Parsons Darrell Nix Elizabeth Baronas Frank Hsieh Liang-Shang Gan Gerald Miwa 《Drug metabolism and disposition》2005,33(6):771-777
Bortezomib [N-(2,3-pyrazine)carbonyl-L-phenylalanine-L-leucine boronic acid] is a potent first-in-class dipeptidyl boronic acid proteasome inhibitor that was approved in May 2003 in the United States for the treatment of patients with relapsed multiple myeloma where the disease is refractory to conventional lines of therapy. Bortezomib binds the proteasome via the boronic acid moiety, and therefore, the presence of this moiety is necessary to achieve proteasome inhibition. Metabolites in plasma obtained from patients receiving a single intravenous dose of bortezomib were identified and characterized by liquid chromatography/mass spectrometry (LC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Metabolite standards that were synthesized and characterized by LC/MS/MS and high field nuclear magnetic resonance spectroscopy (NMR) were used to confirm metabolite structures. The principal biotransformation pathway observed was oxidative deboronation, most notably to a pair of diastereomeric carbinolamide metabolites. Further metabolism of the leucine and phenylalanine moieties produced tertiary hydroxylated metabolites and a metabolite hydroxylated at the benzylic position, respectively. Conversion of the carbinolamides to the corresponding amide and carboxylic acid was also observed. Human liver microsomes adequately modeled the in vivo metabolism of bortezomib, as the principal circulating metabolites were observed in vitro. Using cDNA-expressed cytochrome P450 isoenzymes, it was determined that several isoforms contributed to the metabolism of bortezomib, including CYP3A4, CYP2C19, CYP1A2, CYP2D6, and CYP2C9. The development of bortezomib has provided an opportunity to describe the metabolism of a novel boronic acid pharmacophore. 相似文献
97.
Klein SM Slaughter TF Vail PT Ginsberg B El-Moalem HE Alexander R D'Ercole F Greengrass RA Perumal TT Welsby I Gan TJ 《Anesthesia and analgesia》2000,91(5):1091-1095
Low molecular weight heparin (LMWH) is commonly used to prevent postoperative thromboembolism. Currently, there is no convenient test to measure the degree of anticoagulation from LMWH. This prospective study examines the relationship of thromboelastography and serum anti-Xa concentration in patients treated with enoxaparin. Twenty-four adult patients scheduled for orthopedic surgery using epidural anesthesia were enrolled. Epidural catheters were removed the morning after surgery before the commencement of subcutaneous enoxaparin 30 mg twice daily. Venous blood samples were obtained at 1) the induction of anesthesia (baseline), 2) immediately before the third dose of enoxaparin postoperatively (Day 2-trough), 3) 4 h after the third dose postoperatively (Day 2-peak), and 4) immediately before the fifth dose postoperatively (Day 3-trough). Whole blood samples were obtained for thromboelastography, activated clotting time, and anti-Xa level analyses at each of the four time intervals. At the four sample intervals, the r time (mean +/- SEM). (20 +/- 1, 25 +/- 2, 51 +/- 6, 31 +/- 3 mm) and the k time (9 +/- 0. 7, 12 +/- 1, 27 +/- 5, 14 +/- 2 mm) of the thromboelastograph were significantly correlated with the expected peak and trough levels of LMWH and serum anti-Xa levels (P: < 0.05). At the Day 3-trough, thromboelastograph r times exceeded the normal range in 6 of 25 patients (25%). Prolongation of r time and k time on postoperative Day 3 may indicate an exaggerated response to LMWH. Thromboelastography is a test that could potentially correlate with the degree of anticoagulation produced by low molecular weight heparin. Implications: Thromboelastography is a test that could potentially correlate with the degree of anticoagulation produced by low molecular weight heparin. The r time from the thromboelastogram correlates with serum anti-Xa concentration. 相似文献
98.
Nausea or vomiting occurs frequently after craniotomy. Because of the need for frequent postoperative neurological assessment, an effective antiemetic with minimal sedative side effects is needed. Therefore, we compared ondansetron to droperidol in a randomized, double-blinded, placebo-controlled study. A total of 60 adults requiring elective supratentorial craniotomy received standardized IV anesthesia with 4 mg of ondansetron, 0.625 mg of droperidol, or placebo at skin closure. The incidence of postoperative nausea, emesis, pain and sedation scores, and rescue antiemetic use were recorded at 0, 0.5, 1, 4, 8, 12, 24, and 48 h. All groups were demographically similar. Differences existed for cumulative 8, 12, and 24 h incidences of nausea (24 h, P = 0.03) and emesis (24 h, P = 0.04). Within 4 h, when maximal effect could be expected from treatment, 20% of the ondansetron group, 25% of the droperidol group and 50% of the placebo group received rescue antiemetic (P = 0.12). No differences in pain (P = 0.82) or sedation (P = 0.74) scores were detected. Both ondansetron and droperidol prevent nausea; however, only droperidol reduces emesis after supratentorial craniotomy. The dose of droperidol used was not more sedating than ondansetron. Sustained reduction in nausea and emesis over 24 h indicates a preemptive benefit of prophylactic antiemetic in this surgical population. Implications: Nausea and vomiting after brain surgery are particularly troubling, because effective treatment may cause sedation, making postoperative neurological assessment difficult. Our study shows that both ondansetron and droperidol are effective in reducing nausea, and that droperidol is particularly effective in reducing vomiting. Neither drug caused more sedation than placebo. 相似文献
99.
目的:探讨准分子激光上皮瓣下角膜磨镶术(laserepithelialkeratomileusis,LASEK)手术并发症的类型、产生原因及处理方法。方法:应用LASEK治疗等效球镜为-7.25~14.50D的高度近视眼53例(106眼),对术中和术后产生的并发症进行相关原因分析。结果:LASEK术中并发症主要有上皮瓣剥离困难、破碎、游离、皱褶、局限性缺损等,术后并发症主要有角膜上皮下雾状混浊(Haze)、最佳矫正视力下降、屈光度回退、眩光、上皮瓣溶解等。结论:严格掌握LASEK的手术适应证,熟练掌握手术技巧和正确处理角膜上皮瓣的各种并发症是保证LASEK成功的关键。 相似文献
100.
目的 探讨 Orbcan 系统在测量前房深度、晶状体厚度及眼轴长度中的应用价值。方法 31例 (6 2只眼 )正视眼成人 ,分别用 Orbcan 系统与 A超进行测量比较其前房深度、晶状体厚度及眼球轴长。结果 Orbcan 系统测量中央前房深度、晶状体厚度、眼轴长度分别为 (3.5 2± 0 .2 6 ) mm、(4 .0 9± 0 .2 6 ) m m、(2 5 .5 6± 0 .85 ) m m;A超测量结果分别为 (3.4 5± 0 .36 ) mm、(3.99± 0 .36 ) mm、(2 3.72± 0 .79) mm。两者眼轴指标测量差异有显著性 (P <0 .0 0 1 ) ,其余两指标的差异均无显著性。结论 Orbcan 系统在测量前房深度、晶状体厚度方面具有较高的应用价值 ,但在测量眼轴方面准确性欠佳 相似文献