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1.
Abstract Several methods have been used to predict successful weaning and extubation among chronic obstructive pulmonary disease (COPD) patients. The objective of this study is to determine whether carbon dioxide recruitment threshold (PCO2RT) can be used as adjunct to conventional weaning parameters to predict early weaning and successful extubation. Twelve COPD patients who were ready to be extubated based on conventional weaning parameters were divided into group A ( n = 7) and group B ( n = 5). Group A were those patients with better weaning parameters and hence a higher probability of successful extubation as compared to group B. Carbon dioxide apnoeic threshold (PCO2AT) was obtained by hyperventilating the patient using an increment of two breaths per min until apnoea occurs. At this point, the PCO2AT or the PaCO2 during said apnoeic period was recorded. A dead space of 150 cc is then added to the circuit until the patient starts to breathe as evidenced by the sensitivity trigger indicator. The PCO2 obtained at this period is termed PCO2RT. After weaning for 30 min on a T-tube, another arterial blood gas is determined and this is called the PCO2SB or the CO2 level after 30 min on spontaneous breathing. If the PCO2SB-PCO2RT difference is high with a sensitivity of 85.71% and specificity of 100% vs sensitivity of 57.14% and specificity of 60% using the conventional weaning parameters. Thus an increase in PCO2SB at 30 min T-tube is indicative of impending respiratory pump failure and that other causes of failure to wean must be investigated.  相似文献   
2.
目的:探讨在体外c-myc反义核酸是否可通过阻断人脑胶质瘤细胞中c-myc基因的表达而抑制细胞增殖并诱导分化.方法:人工合成与c-mycmRNA起始码及其后四个密码子互补的寡聚脱氧核苷酸(简称反义核酸)片段,用它处理培养的BT325细胞,观察它对细胞增殖的影响.同时用免疫细胞化学方法检测细胞中Myc蛋白的水平以及能反映胶质瘤细胞分化的S-100和GFAP两种蛋白的水平,分析这些指标的变化.结果:发现4umol/L的c-myc反义核酸明显抑制BT325细胞的增殖和Myc蛋白的合成,且后者发生在加入反义核酸后1h,并持续24h以上,而细胞增殖受抑制要到第5日才明显.从第2日到第5日细胞中S-100和GFAP染色明显加深,反映细胞有分化趋势.用同样长度的无关序列寡聚脱氧核苷酸作对照,则未见上述变化,表明c-myc反义核酸的作用是序列特异性的.结论:c-myc反义核酸可特异地抑制BT325细胞中Myc蛋白的合成和细胞增殖,并能诱导其分化.  相似文献   
3.
我院自 1998年 12月~ 2 0 0 0年 1月施行 Madigan前列腺切除术治疗前列腺增生症 (BPH) 2 6例 ,取得满意效果 ,报告如下。1 临床资料1.1 一般资料 本组病人 2 6例 ,年龄 6 4.8± 5 .5岁 (5 0~80岁 ) ,均有典型 BPH临床表现。 12例急性尿潴留 ,14例残余尿 >6 0 m l。术前经 B超及肛门指检诊断前列腺增生 °19例 , °并向膀胱腔内突出 7例。前列腺最大径 4.6~ 8.5 cm,中叶最大 5 .2 cm× 2 .3cm。合并尿路感染 17例 ;伴有不同程度肾积水肾功能不全 5例 ;合并膀胱结石 3例 ,高血压 14例 ,糖尿病 6例。全部病例均排除膀胱肿瘤等膀胱内…  相似文献   
4.
目的探讨有丝分裂促进因子(MPF)和丝裂原活化的蛋白激酶(MAPK)在小鼠受精卵第一有丝分裂期(M期)中的作用及相互关系.方法分别用MAPK激酶特异性抑制剂(U0126)和MPF特异性抑制剂(roscovitine)抑制受精卵细胞MAPK和MPF的活性,通过同位素测定MAPK和MPF的活性变化,利用显微镜进行形态观察来判定MAPK活性变化对受精卵发育的影响.结果在受精卵第一次有丝分裂期,正常组小鼠受精卵MAPK和MPF的活性均有短暂升高.在U0126处理组,MAPK的活性受抑制会导致受精卵处于M期而不发生分裂,但MPF的活性未受到影响.在roscovitine处理组,MPF的活性受到抑制导致受精卵处于M期不发生分裂,此时MAPK不发生活化.结论 MAPK和MPF的活化对于小鼠受精卵完成有丝分裂是不可缺少的,在有丝分裂期MPF参与MAPK的活化.  相似文献   
5.
目的调查分析354例精神科住院患者共患糖尿病的降糖药物使用情况及合理性。方法利用本院IUS系统查阅2009年11月1日至2010年10月31日精神科住院患者降糖药物用药情况,以WHO规定的药物利用指数(DUI)为评价指标,分析我院精神科住院患者降糖药物应用的合理性。结果吡格列酮、阿卡波糖、格列苯脲DUI均〈1,消渴丸DUI=1,格列喹酮、二甲双弧、胰岛素DUI略大于1,联合用药符合病情。结论本院精神科患者降糖药物使用较为合理,但需提高胰岛素的临床合理应用。  相似文献   
6.
目的探讨神经元特异性烯醇化酶(NSE)、S-100β对肠道病毒71型(EV71)脑炎的早期诊断及脑损伤程度的评估价值。方法选取2008年5月至2010年12月山东大学齐鲁儿童医院重症监护室(PICU)收治的EV71脑炎患儿(EV71脑炎组)100例,同期住院的其他病毒性脑炎患儿89例为其他病毒性脑炎组,非神经系统感染患儿22例为阴性对照组。采用ELISA法检测所有EV71脑炎组及其他病毒性脑炎组患儿急性期及恢复期脑脊液与血清NSE及S-100β蛋白含量,检测阴性对照组患儿急性期及恢复期血清NSE及S-100β蛋白含量及急性期脑脊液NSE及S-100β蛋白含量,并分别进行比较。结果 EV71脑炎组急性期脑脊液、血清及恢复期血清中NSE与S-100β高于阴性对照组,差异均有统计学意义(P均<0.01)。EV71脑炎组急性期脑脊液中NSE低于其他病毒性脑炎组,差异有统计学意义(P<0.05)。EV71脑炎组急性期血清与恢复期脑脊液、血清中S-100β蛋白低于其他病毒性脑炎组,差异有统计学意义(P<0.05)。EV71脑干脑炎组急性期与恢复期脑脊液、血清中NSE显著高于普通脑炎组,差异有统计学意义(P<0.05或P<0.01);EV71脑干脑炎组急性期与恢复期脑脊液、血清中S-100β蛋白显著高于EV71普通脑炎组,差异有统计学意义(P<0.01)。血清与脑脊液中NSE与S-100β有明显相关性(r=0.782、0.734,P均<0.01)。结论监测手足口病患儿脑脊液与血清NSE、S-100β可早期诊断是否合并中枢神经感染,并可评估脑损伤程度及预后。  相似文献   
7.
尼莫地平对急性缺血性脑损伤的干预机制   总被引:1,自引:0,他引:1  
目的:探讨尼莫地平对急性缺血性脑损伤的保护作用。方法:将局灶性脑缺血模型大鼠分为假手术组,缺血组及尼莫地平干预组。测定脑组织PLA2活力,脑细胞内游离Ca^2 浓度,脑含水量及脑组织PLA2表达量的改变。结果:尼莫地平可使缺血后脑细胞内游离Ca^2 浓度,PLA2活性及脑组织含水量明显降低。但对脑缺血后脑组织PLA2mRNA表达降低不明显。结论:尼莫地平能抑制PLA2活性,降低细胞内游离Ca^2 浓度,减轻脑水肿病理改变,对缺血性脑细胞损害有一定保护作用。  相似文献   
8.
本文从急性腹膜透析、血液透析、血液滤过、血液灌流、血液置换、连续性肾脏替代疗法等方法来综述血液净化治疗脓毒症的研究进展。  相似文献   
9.
Background and objective Atypical ‘cardiac‘ chest pain (ACCP) is not usually caused by myocardial ischaemia. Current noninvasive investigations for these symptoms are not yet as accurate as invasive coronary angiography. The latest 64-row multi-detector computed tomography (MDCT) technology is non-invasive, has high specificity and negative predictive values for the detection of significant coronary disease. Our aim was to investigate if this modality can provide more information in the assessment of outpatients with ACCP in addition to established cardiovascular risk scores. Methods Seventy consecutive patients presenting to the outpatient clinic with ACCP underwent 64-row MDCT scan of the coronary arteries. They were categorized into low, medium or high risk groups based upon the Framingham and PROCAM scores. We defined a clinically abnormal MDCT scan as coronary stenosis =50% or calcium score >400 Agatston. Results Fifty-three (75.7%) patients did not have clinically abnormal scans. Framingham score classified 43 patients as low-risk while PROCAM classified 59 patients as low-risk. MDCT scans were abnormal for 18.6% and 22.0% of the respective low-risk group of patients. For patients with medium-to-high risk, 33.3% and 36.4% of Framingham and PROCAM patient groups respectively had abnormal MDCT scans. Conclusion MDCT adds valuable information in the assessment of patients with ACCP by identifying a significant proportion of patients categorized as low-risk to have underlying significant coronary stenosis and coronary calcification by established cardiovascular risk scores.  相似文献   
10.
Background Elderly patients generally have higher occurrence of coronary calcification, increased heart rate and difficulty with prolonged breath-holding. The aim of our study was to investigate the feasibility and accuracy of using 64-row multi-detector computed tomography (MDCT) in the assessment of coronary artery stenoses in elderly patients. Methods One hundred and fifty two patients with suspected or known coronary artery disease were divided into 4 groups according to their age (Group A: 40-49 years, n=34; Group B: 50-59 years, n=57; Group C: 60-69 years, n=48; Group D: 70 years and above; n=13). Coronary CT angiography (CTA) using a 64-row MDCT was performed and the findings were compared with that of conventional coronary angiography (CCA). Using axial images, multi-planar reconstructions (MPR) and maximum intensity projections (MIP), coronary segments of lumen diameter = 1.5mm were analyzed for the presence of significant stenosis (= 50% ). Results Percentages of poor image quality from coronary CTA preventing reliable correlations with CCA were 21%, 14%, 19% and 62% in Groups A to D respectively. Patients in Group D had significantly higher calcium scores compared with the other groups (P<0.001). In patients where CTA images were of acceptable quality, percentages of accurate correlations with CCA were 89.8%, 93.4%, 86.6% and 78.0% for Groups A to D respectively. There were no significant difference in serum creatinine, heart rate and contrast volume between the 4 groups. Conclusions The 64-row MDCT coronary angiography was less accurate and feasible for patients aged 70 years or above due to heavy coronary calcification and inability to perform a satisfactory breath-hold. However, a high diagnostic accuracy with the MDCT is possible in patients aged less than 70 years.(J Geriatric Cardiol 2006;3(1):9-14)  相似文献   
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