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31.
目的评价非肌松、深麻醉状态下,双频谱指数(BIS)反映麻醉深度的准确性。方法选择ASAⅢ级的冠脉搭桥术患者59例,麻醉诱导:静脉注射异丙酚2 mg/kg、舒芬太尼1μg/kg、罗库溴铵0.6 mg/kg,术中麻醉维持采用静脉持续输注异丙酚3-4 mg·kg-1·h-1、舒芬太尼1μg·kg-1·h-1。于麻醉诱导前、麻醉诱导开始后1、2、3、4 min、气管插管后即刻、气管插管后1 min、切皮后即刻和劈胸骨后即刻记录BIS、状态熵(SE)和反映熵(RE)。结果与麻醉诱导前相比,麻醉诱导开始后1、2、3、4 min和气管插管后即刻、气管插管后1 min、切皮后即刻及劈胸骨后即刻BIS、SE和RE均下降(P<0.05)。与SE相比,RE在各观察点均升高(P<0.01)。麻醉诱导期间BIS与SE和RE各时间点观察值之间呈明显正相关,r分别为0.898、0.908(P<0.01)。结论在非肌松、深麻醉状态下,BIS对舒芬太尼复合异丙酚静脉麻醉深度的监测不受肌电活动的影响。  相似文献   
32.
目的 观察异丙酚无痛人工流产时静脉注射缩宫素对血压和心率的影响。 方法 将 90例Ⅰ级 (美国麻醉协会麻醉术前分级 )早期宫内妊娠的患者随机分为 3组 :A组 30例 ,应用 2~ 3mg/kg异丙酚和 1μg/kg枸橼酸芬太尼进行无痛人工流产术 ,手术后期注射缩宫素 1ml,于注射后的 3min内观察收缩压、舒张压和心率变化 ;B组 30例 ,用相同麻醉方法进行无痛人工流产 ,术中不用缩宫素 ,观察指标与方法同于A组 ;C组 30例 ,不用任何麻醉药物进行人工流产 ,在与A组相同的时间注射缩宫素 ,观察指标与方法同于A组。 结果 A组在注射缩宫素后 0 5min ,血压显著下降 ,心率显著增加 ,注射后 2 .5min时 ,血压和心率基本恢复到注射前水平。B组和C组无明显血压下降。 结论 异丙酚无痛人工流产时注射常规剂量缩宫素后可致血液循环短暂严重波动 ,应引起临床妇产科医师高度重视 ,特别是对心功能储备较差的患者更应关注。  相似文献   
33.
目的探讨听觉诱发电位指数(AAI)指导全凭静脉麻醉期间病人输注异丙酚的效果。方法择期全麻下行腹腔镜胆囊切除术病人60例,ASAⅠ或Ⅱ级,随机分为2组(n=30):试验组(Ⅰ组)和对照组(Ⅱ组)。静脉诱导气管插管后,持续输注0.2μg·kg-1·min-1瑞芬太尼以维持合适的麻醉深度。Ⅰ组通过监测AAI调节异丙酚输注速率,使AAI维持在30以下,Ⅱ组根据病人血压及心率调节异丙酚输注速率,每5分钟增减0.01 mg·kg-1·min-1异丙酚。记录气腹前(T1)、气腹后(T2)、分离胆囊(T3)、腹腔冲洗(T4)、手术结束(T5)时2组的血压、心率、AAI和输注异丙酚的速率,同时记录2组异丙酚、维库溴铵、瑞芬太尼用量、术毕睁眼时间、应答时间和拔管时间。结果2组各时间点AAI差异有统计学意义(P<0.05),与Ⅱ组相比,Ⅰ组输注异丙酚速率以及总用量减少(P<0.05)。术后24 h随访病人均无术中知晓。结论AAI指导全凭静脉麻醉输注异丙酚用于腹腔镜胆囊切除术病人,可较好的控制麻醉深度,指导合理用药,避免病人术中知晓。  相似文献   
34.
异丙酚对脊髓缺血再灌注损伤大鼠脊髓细胞凋亡的影响   总被引:7,自引:1,他引:6  
目的 探讨异丙酚对脊髓缺血再灌注损伤大鼠脊髓细胞凋亡的影响。方法成年雄性清洁级Wiser大鼠60只,体重200~250g,随机分为异丙酚组(A组)和缺血再灌注组(B组),每组30只,采用改进的Zivin等的方法制备脊髓缺血再灌注模型,缺血的同时A组腹腔注射异丙酚100mg/kg,B组注射等量生理盐水。每组分别于再灌注6h、1d、2d、3d、7d时处死6只大鼠。根据Tador评分评价大鼠后肢神经功能损伤情况,电镜下观察脊髓的病理学变化,用免疫组化法测定脊髓cyclinD1阳性细胞表达,原位末端标记法(TUNEL法)检测凋亡细胞,计算凋亡指数。结果A组脊髓损伤及后肢神经功能损伤均较B组轻,A组脊髓神经细胞凋亡指数及cyclinD1表达均低于B组(P〈0.05或0.01)。结论异丙酚对脊髓缺血再灌注损伤有一定的保护作用,其机制与下调脊髓cyclinD1表达,抑制神经细胞亡有关。  相似文献   
35.
36.
In order to estimate the diagnostic validity of chemical fecal occult blood tests, i.e. orthotolidine (Shionogi A) and guajac (Shionogi B) slides for detecting cancers of the esophagus, stomach and colorectum, the authors followed up all the examinees (n=3,449) of comprehensive medical check-ups at the Center for Adult Diseases, Osaka, by means of record linkage to the Osaka Cancer Registry's files. Then, diagnostic validity was calculated based on the results of two years' follow-up. Sensitivity for the respective cancers was 20.0%, 11.8% and 62.5% for Shionogi A, and 20.0%, 5.9% and 43.8% for Shionogi B slides. Likelihood ratio for the respective cancers was 1.4, 0.8 and 4.5 for Shionogi A, and 3.3, 1.0 and 7.5 for Shionogi B. Specificity was analogous among the three cancer sites, being 86% for Shionogi A and 94% for Shionogi B. These results suggest that the diagnostic validity of chemical occult blood tests for detecting cancers of the esophagus and the stomach is very poor, and therefore imply that close examinations of these sites for screening positives is unnecessary in mass screenings for colorectal cancer.  相似文献   
37.
Here we report the finding of enzymatic activity that specifically cleaves DNA containing 8-hydroxyguanine (oh8Gua) residues in various mammalian cells. To detect this activity, we used a synthetic double-stranded DNA containing a single oh8Gua at a defined position as the substrate, and analyzed the products of enzymatic digestion by polyacrylamide gel electrophoresis. Two cleavage sites near the oh8Gua residue were detected with partially purified fractions from cow brain and rat liver, and also with preparations from all mammalian tissues examined. These results suggest that enzymatic activity for the removal of oh8Gua from DNA is widely distributed in mammalian cells.  相似文献   
38.
A case-control study to evaluate the efficacy of lung cancer screening conducted by us showed that lung cancer screening may reduce the mortality of the disease up to 28%. Assuming this efficacy is unbiased, and that the screening rate is 51.6%, which was observed in the control group in the above study, the number of lung cancer deaths prevented by screening in the study period was calculated to be 47 for males and females combined. In the same study population, screen-detected lung cancer patients (N = 207) in the same study period were followed and the 7-year survival rate (46.9%) was compared to the 5-year survival rate (11.3%) obtained by the Osaka Cancer Registry, in which screen-detected lung cancer patients were only 1.8%. The number of lung cancer deaths prevented by screening, estimated by the difference in the above two survival rates, was 74 (95% confidence interval; 55–93). The number of lung cancer deaths prevented by screening estimated from the case-control study was significantly lower than that estimated from the survival analysis. This indicates that the efficacy of lung cancer screening estimated by the case-control study was within the range that could be explained by the actual long-term survivors among the screen-detected patients in the study population.  相似文献   
39.
The core sequence of the enhancer of murine leukemia virus (MuLV) long terminal repeat is highly conserved in a large number of MuLV strains and appears to play an essential role when SL3-3 or Moloney strains induce T cell lymphoma in mice. We found by using the electrophoretic mobility shift assay that a polyomavirus enhancer core-binding protein, PEBP2, bound to this core motif of MuLV. We also noted that PEBP2 in several hematopoietic cell lines derived from B lymphocyte, macrophage and myelocyte lineages migrated significantly faster than the authentic PEBP2 detected in NIH3T3 (ibroblasts. Interestingly, PEBP2 detected in the cell lines of T lymphocyte lineage appeared to contain both types, which were indistinguishable in electrophoretic mobility from those of NIH3T3 and of B lymphocyte, macrophage and myelocyte lineages. The treatment of the nuclear extract containing PEBP2 with phosphatase generated PEBP3, which is a subcomponent of PEBP2 and retained the same DNA-binding specificity as PEBP2. The altered mobility of hematopoietic cell-derived or T lymphocyte-derived PEBP2 was found to be due to the alteration of the mobility of PEBP3. Based on the distinct mobility of PEBP2/3 of T lymphocytes from those of other hematopoietic cells, we discuss the implication of PEBP2 in MuLV-induced T cell leukemia and T cell-specific gene expression.  相似文献   
40.
Strain difference of susceptibility to 4-nitroquinoline 1-oxide (4NQO)-induced squamous cell carcinomas of the tongue among Dark-Agouti, Long-Evans, Sprague-Dawley, ACI/Ms, Fischer 344, Donryu and Wistar/Furth rats was surveyed by evaluating the survival times, incidences and sizes of developed tumors as markers of susceptibility. Administration of 4NQO dissolved in drinking water induced squamous cell carcinomas in various sites of the upper digestive tract mucosa of all the experimental male and female rats of the seven strains. Regarding the mean survival times, Wistar/Furth rats survived much longer than any other strain of rats, and Dark-Agouti showed the shortest survival. The incidence of large, mass-type carcinomas of the tongue of Dark-Agouti rats was higher than in any other strain of rats, while that of Wistar/Furth rats was the lowest. Subsequently the mitotic activity and bromodeoxyuridine incorporation in the tongue epithelium of Dark-Agouti and Wistar/Furth rats were estimated after a short-term administration of 4NQO. There was a pronounced difference between the two strains of rats, because the proliferative responses of the tongue epithelium of Dark-Agouti rats to the 4NQO stimulation were much higher than those of Wistar/Furth rats. These results indicated that there are marked differences in the susceptibility to 4NQO-induced tongue carcinoma among the seven strains of rats, and that Dark-Agouti and Wistar/Furth rats could be useful as models of highly and poorly susceptible strains, respectively, for further genetic analysis.  相似文献   
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