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61.
Methods: Untrained subjects were asked to perform CPR on a manikin with and without the assistance of audio prompts. All subjects were then trained in CPR, and retested them eight weeks later.

Results: Untrained subjects who performed CPR first without audio prompts performed poorly, with only (mean (SD)) 24.5% (32%) of compressions at the correct site and depth, a mean compression rate of 52 (31) per minute, and with 15% (32%) of ventilatory attempts adequate. Repeat performance by this group with audio prompts resulted in significant improvements in compression rate (91(12), p = 0.0002, paired t test), and percentage of correct ventilations (47% (40%), p = 0.01 paired t test), but not in the percentage correct compressions (23% (29%)). Those who performed CPR first with audio prompts performed significantly better in compression rate (87 (19), p = 003, unpaired t test), and the percentage of correct ventilations (51 (34), p = 0.003 unpaired t test), but not in the percentage of correct compressions (18 (27)) than those without audio prompts. After training, CPR performance was significantly better than before training, but there was no difference in performance with or without audio prompts, although 73% of subjects commented that they felt more comfortable performing CPR with audio prompts.

Conclusions: For untrained subjects, the quality of CPR may be improved by using this device, while for trained subjects the willingness to perform CPR may be increased.

  相似文献   
62.
基于光电传感器的多段脉搏波传播速度检测系统的研制   总被引:2,自引:4,他引:2  
采用了一种以反射式和透射式红外光光电传感器和单片机为基础,用同步检测心电信号、桡动脉脉搏波、手指脉搏波信号来测定桡动脉和外周动脉脉搏波传播速度的方法,研制一种无创的多段脉搏波传播速度检测系统。在软件编程中脉搏波周期信号的识别是以心电R波峰值为基准,同时再根据它们之间的时延关系进一步确定脉搏波的波峰与波谷的范围,提高检测准确性及精度。该系统通过检测心电、桡动脉脉搏波和手指脉搏波信号可获得多段脉搏波传播速度参数,具有较高的检测精度和良好的应用前景。  相似文献   
63.
目的:体外观察甲状旁腺激素对大鼠成骨细胞增殖和护骨素分泌的调节作用。方法:实验于2005-06/2006-05在四川大学华西医院生物治疗国家重点实验室干细胞与组织工程研究室完成。采用酶消化法和骨组织块法联合分离培养新生SD大鼠颅骨成骨细胞,间歇加药方法将不同浓度0,10-6,10-7,10-8,10-9mol/L甲状旁腺激素作用于大鼠成骨细胞(0mol/L作为空白对照组),经碱性磷酸酶染色及钙结节茜素红染色证实培养的成骨细胞后,采用四甲基偶氮唑盐比色法检测细胞增殖能力,蛋白免疫印迹测定护骨素的分泌量。结果:①成骨细胞的形态变化:倒置相差显微镜下可见培养的成骨细胞呈短梭形、三角形和多边形。碱性磷酸酶染色光镜下可见成骨细胞胞浆中分布特征性蓝紫色细颗粒;成骨细胞的钙结节在镜下可见部分细胞聚集一起呈"集落状"生长。②成骨细胞增殖率:10-6~10-9mol/L浓度甲状旁腺激素对成骨细胞增殖均显示刺激作用,与空白对照组相比,差异显著(P<0.05),增殖率以10-8mol/L甲状旁腺激素组最高。③成骨细胞护骨素的表达:甲状旁腺激素下调成骨细胞中护骨素的分泌,与空白对照组相比,10-6mol/L甲状旁腺激素组抑制作用最明显(P<0.01),无显著剂量依赖性。结论:甲状旁腺激素对体外培养成骨细胞的增殖具有明显促进作用,通过下调成骨细胞中护骨素的分泌,促进破骨细胞生成、活化,促进骨吸收。  相似文献   
64.

Background  

The tumour supressor gene TP53 is thought to be involved in neural apoptosis. The polymorphism at codon 72 in TP53 and the long form variants of the upstream variable number of tandem repeats (uVNTR) polymorphism in the dopamine D4 receptor (DRD4) gene are reported to confer susceptibility to schizophrenia.  相似文献   
65.
The impact of family and personal caregivers on inpatients with fall-related injuries in a Taiwanese medical center is investigated in this study. Taiwan has a prevalent custom for families to accompany their hospitalized loved ones during hospital stays. During the 95-day data collection period, 228 falls occurred. Results showed that if no family members were present when a patient fell, the fall-related injury was less serious. Nurses in Taiwan tend to depend on family members to help provide patient care. Regardless of whether an inpatient has a family member present, frequent bedside nursing visits are important to prevent falls.  相似文献   
66.
目的:探索糖稳态调节细胞定向分化的基因改造方案思路.方法:①研究构建的解除干细胞分化抑制状态的信号传导与转录激活因子-3(STAT-3)基因载体,检测其介导目的基因感染ARIP等细胞基因表达;②研究构建的活化配体DL诱导N信号、在"旁侧抑制"过程中扮演重要角色的Kuzbanian(KUZ)基因载体在转基因小鼠表达后糖稳态调节细胞的分化.结果:在完成的STAT-3腺病毒基因载体生产了腺病毒,用带有目的基因的腺病毒对ARIP靶细胞进行感染,3 d后,荧光显微镜观察时,活细胞、固定液固定细胞均看到了构建基因中绿色荧光蛋白成功、高效的阳性表达报告.在完成的Kuzbanian(KUZ)基因载体构建、转基因、动物模型、小鼠品系鉴定后,用非放射性原位杂交实验对胰腺靶细胞的mRNA进行检测,获得了预期的阳性结果.结论:通过用某些分化抑制性基因的显性失活形式(DN)竞争性预先解除干细胞分化的抑制状态,然后再定向分化诱导使之朝向期望的目标细胞方向分化,可能是糖稳态细胞定向分化的可行途径之一.  相似文献   
67.
Wang JJ  Tzeng JI  Ho ST  Chen JY  Chu CC  So EC 《Anesthesia and analgesia》2002,94(3):749-53; table of contents
Tropisetron is a 5-hydroxytryptamine subtype 3 receptor antagonist that is primarily used in the prevention of chemotherapy-induced nausea and vomiting. We evaluated the prophylactic effect of tropisetron on postoperative nausea and vomiting associated with epidural morphine. Dexamethasone and saline served as controls. One-hundred twenty women (n = 40 in each of three groups) undergoing abdominal total hysterectomy under epidural anesthesia were enrolled in this randomized, double-blinded, and placebo-controlled study. At the end of surgery, Group 1 received IV tropisetron 5 mg, whereas Groups 2 and 3 received dexamethasone 5 mg and saline, respectively. We found that tropisetron did not significantly reduce the occurrence of nausea and vomiting associated with epidural morphine. Dexamethasone, however, reduced the total incidence of nausea and vomiting from 59% to 21% (P < 0.01) and the percentage of patients requiring rescue antiemetic from 38% to 13% (P < 0.05). We conclude that IV tropisetron 5 mg did not prevent the occurrence of postoperative nausea and vomiting associated with epidural morphine. IV dexamethasone 5 mg was effective for this purpose. IMPLICATIONS: We compared the prophylactic IV administration of tropisetron 5 mg to prevent postoperative nausea and vomiting (PONV) associated with epidural morphine with dexamethasone 5 mg and saline in women undergoing hysterectomy. We found that tropisetron 5 mg did not significantly reduce the occurrence of PONV associated with epidural morphine. Dexamethasone 5 mg was effective for this purpose.  相似文献   
68.
Vascular gene therapy: a reality of the 21st century   总被引:8,自引:0,他引:8  
Current therapies for the treatment of atherosclerotic vascular disease are aimed at either disrupting or bypassing flow-limiting lesions. Preventative strategies are necessary to decrease the burden of disease but are limited by genetic predispositions to certain diseases and the body's innate response to injury. Gene therapy, defined as the purposeful therapeutic overexpression or attenuation of a gene product, has enormous potential benefits in vascular disease prevention and treatment strategies. This article reviews the scientific considerations involved in the development of gene therapy strategies and outlines some of the gene products that are currently being used. These interventional genetic approaches will be reviewed in the context of specific vascular disease processes, including atherosclerosis, restenosis, and thrombosis. Gene therapy will serve an enhancing and adjuvant role to evolving surgical therapies.  相似文献   
69.
70.
Hsieh PF  Chia LG  Ni DR  Cheng LJ  Ho YP  Tzeng SF  Chang MH  Hong JS 《Neuroreport》2002,13(3):277-280
Inflammation and neuronal degeneration of the substantia nigra (SN) occur in Parkinson's disease (PD). We studied the effects of intranigral lipopolysaccharide (LPS) injection on adult Sprague-Dawley rats. Locomotor activity measurement, neurotransmitter determination and perfusion fixation for immunohistochemistry were done on the 7th day. Bilateral LPS injection increased locomotor activity 2- to 3-fold. In the SN, dopamine (DA) and serotonin (5-HT) decreased but the ratios dihydroxyphenylacetic acid (DOPAC)/DA, homovanillic acid (HVA)/DA and 5-hydroxyindole-acetic acid (5-HIAA)/5-HT increased. In the striatum, DA, DOPAC, HVA, 3-methoxytyramine and epinephrine decreased but HVA/DA and 5-HIAA/5HT ratios increased. Unilateral LPS decreased dopamineric neurons ipsilaterally but increased contralaterally. This study provides the first evidence of behavioral hyperactivity, epinephrine suppression and neuronal plasticity in the LPS model of PD.  相似文献   
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