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91.
余度 《医疗设备信息》2006,21(5):65-66,69
本文主要介绍常导型MR磁体温度控制部分的组成、原理及常见故障的分析和维修。  相似文献   
92.
目的 探讨维生素E油浴应用于早产儿治疗中的作用。方法 对2001年3月~2003年12月我院住院的42例患肺透明膜病的早产儿,28例患新生儿硬肿症的早产儿及随机抽取的50例早产儿,三种情况早产儿分别随机分为治疗组和对照组,对照组给予常规治疗,治疗组在常规治疗的基础上加用维生素E油浴。结果 治疗组治疗的时间均短于对照组(P〈0.05)。结论 维生素E油浴在早产儿治疗中有促进疾病好转和恢复的作用,并且未发现维生素E油浴的不良反应。  相似文献   
93.
乌司他丁对原位肝移植术肺损伤的保护作用   总被引:1,自引:0,他引:1  
目的:观察原位肝移植术(OLT)中肺损伤的程度,探讨乌司他丁(UTI)对OLT中肺损伤的保护作用.方法:40例择期行OLT手术患者随机分为UTI组和对照组各20例,UTI组(n=20)切皮后将UTI 100万单位加入100mL生理氯化钠溶液,持续静脉输注,之后每隔4 h重复使用.对照组(n=20)以等容量生理氯化钠溶液代替.于麻醉后切皮前、无肝前期120 min、无肝期30 min、新肝期10 min、新肝期60 min和术毕对肺顺应性、吸气阻力、呼气阻力、峰值压力和平台压力进行观察.结果:在新肝期10 min、新肝期60 min和术毕时,对照组的肺顺应性显著下降,吸气阻力、呼气阻力、峰值压力和平台压力显著升高(P<0.05).UTI组的吸气阻力、呼气阻力、峰值压力和平台压力值均明显低于对照组(P<0.05),而肺顺应性值明显高于对照组(P<0.05).结论:0LT过程造成肺损伤,UTI在OLT中对肺损伤有保护作用.  相似文献   
94.
舌诊作为中医诊病的一种独特方法,是中医望诊的重要组成部分,已越来越受人们的重视。近代,开展了大量舌诊客观化、现代化的研究。其中,对镜面舌从体内显微观察、生理、生化、病理检查等方面展开了较深层次的研究  相似文献   
95.
96.
建立了检测血清中异丙酚的反相高效液相色谱-荧光法.血清样品经含内标百里酚的丙酮溶液直接沉淀后,采用KR100-5 C18柱,甲醇-0.1%三氟醋酸溶液(80:20)为流动相,荧光激发波长为276nm,发射波长为307nm.异丙酚在0.05~12.8μg/ml范围内与峰面积比线性关系良好.检测限为150pg,异丙酚和百里酚的提取回收率均大于90%,批内、批间精密度为1.11%~6.88%.  相似文献   
97.
AIM: To observe the effects of three cytokines on the apoptosis of Tf-1 cells induced by y irradiation and investigate the relationship between apoptosis and caspase-3 activity. METHODS: Different cytokines GM-CSF, IL-3 and GM-CS/IL-3 fusion protein were added into the irradiated Tf-1 cells. MTT assay, morphology, flow cytometry, and DNA fragmentation assay were used to observe the effects of cytokines on apoptosis. The caspase-3 activity was determined with a fluorocytometer. RESULTS: Irradiated Tf-1 cells showed typical morphological characteristic of apoptosis demonstrated by transmission electron microscopy and were accumulated in G0/G1 phase. In the groups treated with growth factors after irradiation, three cytokines significantly increased the viability rate, distinctly decreased the apoptosis rate and the proportion of DNA fragmentation. When Tf-1 cells were irradiated by y  相似文献   
98.
压电免疫传感器两种抗体固定方法的比较研究   总被引:4,自引:4,他引:4  
目的比较压电免疫传感器两种抗体固定方法的优劣,选择压电免疫传感器抗体敏感膜固定的最佳方法. 方法分别采用巯基化方法和蛋白A(SPA)固定法将抗人胰岛素单克隆抗体固定在压电免疫传感器金膜电极表面,比较不同抗体工作浓度、不同浓度标准溶液反应条件下抗体固定量、一致性以及传感器响应能力如频率变化、反应时间、检测线性范围以及反应非特异性等. 结果两种固定方法制备的压电免疫传感器其检测灵敏度、反应时间相当,但巯基化固定方法抗体固定量大、一致性好、检测线性范围较宽、非特异反应低. 结论抗体巯基化法制备的压电免疫传感器具有检测范围宽、非特异反应低等优点,是免疫传感器抗体敏感膜制备的理想方法.  相似文献   
99.
目的:探讨影像组学方法在术前预测直肠非黏液性腺癌淋巴结转移中的价值。方法:回顾性分析91例手术病理切片证实为直肠非黏液性腺癌患者的影像学资料,其中61例为训练样本,30例为验证样本。基于全瘤体积,从每个原发病灶术前高分辨T2加权成像(T2-weighted imaging,T2WI)图像中提取影像组学特征1 301个。基于训练样本,利用最小绝对收缩和选择算子(the least absolute shrinkage and selection operator,LASSO)逻辑回归方法筛选关键特征并构建影像组学分类器。采用受试者工作特征(receiver operating characteristic,ROC)曲线评价影像组学分类器的辨别效能,并将其与形态学标准进行比较。在验证样本中验证影像组学分类器的价值。结果:由5个影像组学特征构建的分类器与淋巴结转移状态有关(P<0.001)。在训练样本和验证样本中,影像组学分类器诊断淋巴结转移的曲线下面积分别为0.874(95% CI:0.787~0.960)和0.878(95% CI:0.727~1.000),形态学标准诊断淋巴结转移的曲线下面积分别为0.619(95% CI:0.487~0.752)和0.556(95% CI:0.355~0.756)。无论是训练样本还是验证样本,影像组学分类器的诊断效能均高于形态学标准(均P<0.05)。结论:影像组学分类器可术前个体化预测直肠非黏液性腺癌淋巴结转移,而且其诊断效能高于形态学标准。  相似文献   
100.
BACKGROUNDThe cardiovascular hazards of total homocysteine (tHcy) are long known. In addition, despite the acknowledgment on the importance of low ankle-brachial index (ABI) (< 0.9), borderline ABI (0.91-0.99) was once commonly overlooked. This study aims to explore the independent and joint effect of tHcy level and borderline ABI on all-cause death in hypertensive population.METHODSThis study included 10,538 participants from China H-type Hypertension Registry Study. ABI was described into two groups: normal ABI (1.00-1.40) and borderline ABI. tHcy level was also divided into two groups: < 15.02 and ≥ 15.02 μmo/L. Four groups were analyzed, using COX proportional hazard regression model, separately and pairwise to observe the independent and joint effect on all-cause death.RESULTSA total of 126 (1.2%) deaths were observed in the 1.7 years follow-up time. Borderline ABI has a higher predicted risk of death than normal ABI (HR = 1.87, 95%CI: 1.17-3.00) after adjusting for potential covariates. Compare with tHcy level < 15.02 μmo/L (low tHcy), those with tHcy ≥ 15.02 μmo/L (high tHcy) had higher risk to event outcome (HR = 1.99, 95% CI: 1.30-3.05). According to the cumulative hazard curve, group with borderline ABI and high tHcy level has significantly higher altitude and larger increasing rate over follow-up period compare to other groups. Among those with borderline ABI, participants with high tHcy had higher death risk than those with low tHcy, nevertheless, no significant different between borderline and normal ABI among those with low tHcy levels.CONCLUSIONSBorderline ABI and tHcy level both have independent predictive value on all-cause death. The combined group of borderline ABI and high tHcy has highest risk factor of outcomes, which suggested the mutual additive value of borderline ABI and tHcy. More attention should be given to the importance of borderline ABI in hypertensive population, especially with elevated tHcy level.

Homocysteine (Hcy) is a sulfur-containing, non-proteinogenic amino acid synthesized through the transmethylation of amino acid methionine from one-carbon metabolism. Elevated plasma total homocysteine (tHcy) level is associated with endothelial dysfunction, increased blood coagulation, and metabolic disturbance, promoting cardiovascular diseases, stroke, and coronary artery disease.[1,2] Notably, patients with high Hcy levels and concomitant hypertension were suggested to be at particularly higher risk.[3] Moreover, increasing studies have explored a positive association between advanced Hcy level with all-cause mortality. According to a recent dose-response meta-analysis, for each 5-μmol/L increment of tHcy levels, the risk for all-cause mortality increased by 33.6%.[4]The ankle-brachial index (ABI) is an effective, well-established measure that is commonly used in the diagnosis of peripheral artery disease (PAD),[5] meanwhile was well studied as an important indicator of atherosclerosis and CVD events.[6] Although ankle-brachial index (ABI) ≤ 0.90 has been recognized as the threshold value for abnormal/low ABI, which was proven to increase the risk of all-cause mortality,[7] a study from the American Heart Association has suggested ABI between 0.91 and 1.00 should be considered as “borderline area” in terms of cardiovascular risks,[8] considering of prior probability and sensitivity of ABI calculation. Emerging studies have aimed to explore the predictive value of borderline ABI,[9-11] however, controversy remains because of limited and inconsistent data. The current study aimed to explore the individual and joint effect of borderline ABI and tHcy on all-cause mortality among hypertensive adults. Although ABI level ≤ 0.90 has been and is going to remain significant in clinical practice, we believe broader concern should be placed on borderline ABI, especially for its value in risk differentiation and identification. To the best of our knowledge, there are no similar previous studies.  相似文献   
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