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71.
无创正压通气不同压力支持水平对正常人呼吸做功的影响   总被引:2,自引:0,他引:2  
目的 :观察无创正压通气 (NIPPV)不同压力水平对正常人呼吸做功的影响 ,为临床合理地应用NIPPV提供理论依据。方法 :选择 9例正常人行NIPPV并寻找出“最舒适”的吸气压力水平 (IPAP) ,在此压力基础上增加或减少 2 5 %的压力 ,构成低IPAP、最舒适IPAP和高IPAP三个压力水平 ,每一IPAP水平通气 15min以上 ,比较不同压力水平呼吸做功改变。结果 :受试者认为“最舒适”的IPAP为 (11.33± 3.2 0 )cmH2 O ,EPAP为 (4 .5 6± 0 .88)cmH2 O[相当于PSV水平为 (6 .77± 3.2 0 )cmH2 O]。与自主呼吸相比 ,NIPPV增加VE的同时 ,总的呼吸做功(Wtot)明显增加 (P <0 .0 5 ) ,而受试者吸气肌做功占总的吸气做功的百分比 (Wi,p/Wi)明显减少 (P <0 .0 5 )。在最舒适IPAP时 ,Wi,p/Wi降低到基础值的 14 %± 9%。这种变化趋势与IPAP的水平相关。结论 :NIPPV可以显著降低吸气肌肉做功。吸气肌做功减少的比例与IPAP的水平相关。研究的结果为NIPPV时PSV的参数设定提供了生理学的依据。  相似文献   
72.
Objective To develop and evaluate the effectiveness of a breast cancer prevention decision aid for women aged 50 and older at higher risk of breast cancer. Design Pre‐test–post‐test study using decision aid alone and in combination with counselling. Setting Breast Cancer Risk Assessment Clinic. Participants Twenty‐seven women aged 50–69 with 1.66% or higher 5‐year risk of breast cancer. Intervention Self‐administered breast cancer prevention decision aid. Main outcome measures Acceptability; decisional conflict; knowledge; realistic expectations; choice predisposition; intention to improve life‐style practices; psychological distress; and satisfaction with preparation for consultation. Results The decision aid alone, or in combination with counselling, decreased some dimensions of decisional conflict, increased knowledge (P < 0.01), and created more realistic expectations (P < 0.01). The aid in combination with counselling, significantly reduced decisional conflict (P < 0.01) and psychological distress (P < 0.02), helped the uncertain become certain (P < 0.02), and increased intentions to adopt healthier life‐style practices (P < 0.03). Women rated the aid as acceptable, and both women and practitioners were satisfied with the effect it had on the counselling session. Conclusion The decision aid shows promise as a useful decision support tool. Further research should compare the effect of the decision aid in combination with counselling to counselling alone.  相似文献   
73.
Abstract: This open clinical study was aimed at testing the hypothesis that an intravascular oxygenator (IVOX) may help to perform permissive hypoventilation in 10 patients with severe ARDS. After initial evaluation, we tried to reduce ventilator settings before and after IVOX implantation. Before IVOX, poor clinical tolerance and worsening oxygenation did not allow for a significant decrease in ventilator settings. With IVOX, peak inspiratory pressure (PIP) was reduced from 47 to 39 cm H2O (p = 0. 005) and minute ventilation from 13 ± 3. 5 to 11 ± 3 L/min. CO2 removal by IVOX allowed a significant decrease in Paco2 from 66 ± 15 to 59 ± 13 mm Hg. Improvement of oxygenation with IVOX was not signify cant. Furthermore, interruption of oxygen flow through IVOX did not change oxygenation variables. Tolerance of the IVOX device was good, but insertion of the device was followed by a significant decrease in both cardiac index and pulmonary wedge pressure. In conclusion, IVOX improves tolerance of hypoventilation by limiting hypercapnia in ARDS patients. These preliminary results must be confirmed by a randomized controlled study  相似文献   
74.
A cross-sectional and comparative research design with convenience sampling was used to recruit pregnant women from prenatal clinics in southern Taiwan between 2002 and 2003 to examine the differences in perceived stress, social support, and maternal psychosocial adaptation among women with different severities (mild or less than mild, moderate, and severe) of nausea and vomiting during pregnancy. A total of 150 pregnant women participated in this study. One-way analysis of variance indicated that perceived stress was significantly different among the 3 groups. The least significant difference post-hoc test revealed that pregnant women with mild nausea and vomiting had significantly lower stress than did pregnant women with severe nausea and vomiting. The severity of nausea and vomiting was significantly associated with the Prenatal Self Evaluation Questionnaire subscales for "acceptance of pregnancy" and "fear of helplessness and loss of control in labor." Social support and maternal psychosocial adaptation were not significantly different among these three groups. The degree of perceived stress and maternal psychosocial adaptation may be related to the severity of nausea and vomiting during pregnancy.  相似文献   
75.
舒越 《中国厂矿医学》2004,17(4):269-270
目的 介绍应用经皮内镜下胃造口术(PEG)实施肠内营养支持。方法 在内镜引导下行胃造口术.7例病人均予以肠内营养。结果 7例病人置管8次,成功率100%,6例经治疗后恢复情况好,无严重并发症。结论在肠内营养输注途径中PEG具有创伤小、时间短、经济,安全等特点。易于护理和长期使用。  相似文献   
76.
基于混合遗传算法的心脏病决策支持系统研究   总被引:1,自引:0,他引:1  
将遗传算法和 BP算法相结合 ,建立了一个基于混合遗传算法的心脏病决策支持系统来鉴别诊断五种常见心脏病 (冠心病 ,高血压性心脏病 ,风湿性心脏病 ,慢性肺原性心脏病和先天性心脏病 )。一个含有 35 2份心脏病的数据库用来构建和测试了该系统。实验结果表明 ,构建的系统对这五种心脏病均有较好的诊断识别率 ,系统的平均识别准确性达 90 .6 % ,各疾病的用户准确性和程序准确性均大于 85 .0 % ,表现出良好的心脏病的临床诊断决策支持能力  相似文献   
77.
Hepatocyte isolation from pig livers after warm ischaemic injury   总被引:9,自引:0,他引:9  
Abstract Hepatocyte cultures have been used extensively for a wide variety of physiological, pharmacological and experimental studies. The warm ischaemic period before isolation is kept to a minimum to achieve a high yield of cells isolated and a good viability for culture. We have recently introduced a new concept of liver resuscitation after warm ischaemia that is based on a 3-h reperfusion period with an improved perfusate and simultaneous dialysis. In this study, we applied the new technique for hepatocyte isolation from livers subjected to 80 min of complete ischaemia at 37 °C. Cell yield was improved by a resuscitating perfusion from 58% to 73% and viability from 39% to 76%.  相似文献   
78.
本实验对腹腔感染造成多器官衰竭的动物观察了不同全静脉营养配方在代谢支持中的作用。结果显示:在兔感染性多器官衰竭早期,实行代谢支持能够不同程度地增加体重、促进蛋白质合成和扭转负氮平衡。适当减低糖供给的非蛋白热量可以减轻应激反应,增加氮保留和改善肺功能。供给氨基酸过多则增加应激反应、增加尿氮排出和加重呼吸负担。  相似文献   
79.
OBJECTIVE: The GRIF automated feedback system produces real-time comments on the appropriateness of diagnostic tests ordered by general practitioners (GPs) based on recommendations from accepted national and regional practice guidelines. We investigated the experiences of GPs with this system and, more specifically, with the recommendations produced by the system as well as their views on using this system in daily practice. SETTING: We tested the GRIF system in an experiment in a laboratory setting and in a daily practice trial. STUDY PARTICIPANTS: General practitioners. INTERVENTION: In the laboratory experiment, GPs used the GRIF system to assess the appropriateness of 30 request forms. Each of the GPs was confronted with requests they had submitted to the diagnostic unit of the hospital in the past. In the field trial, the GRIF system was applied during patient consultations for 1 year. MAIN OUTCOME MEASURES: We measured GPs' satisfaction with the system using a questionnaire, and also conducted group discussions (in the laboratory experiment) and in-depth interviews (in the field trial) to elicit GPs' opinions of and experiences with the system. In addition, we explored GPs' reasons for not accepting the comments offered by the GRIF system. RESULTS: The results show that the GPs in the laboratory experiment had more positive attitudes towards the system compared with participants in the field trial. All discussion groups and most of the GPs in the field trial regarded receiving the immediate feedback during the test ordering process as an important advantage. The most frequently mentioned reason to reject the recommendation was disagreement with the content and/or the recommendations in the practice guidelines. CONCLUSION: Apart from securing agreement on guideline content, a prerequisite for using GRIF in daily practice on a large scale is that more attention is paid to promotion of the guidelines and their adoption, and stimulation of a positive attitude towards the practice guidelines among the users.  相似文献   
80.
目的探讨不同心理健康状况的贫困大学生的防御方式和社会支持特点及其关系。方法采用防御方式问卷(DSQ)、社会支持评定量表、症状自评量表(SCL-90)对302名中医院校贫困大学生进行测评。结果贫困生的心理健康水平低于国内青年常模,但在人口学统计变量上的差异不显著;不同心理健康水平的学生的防御方式和社会支持均具有显著性差异,心理健康状况差的学生较心理健康好的学生更多地使用不成熟的防御策略,且在客观支持、主观支持、对支持的利用度和总分上均显著地低于心理健康状况好的学生;不成熟的防御策略对心理健康具有显著影响。结论贫困生的心理健康与防御方式和社会支持之间具有显著的关联性,应从转导不成熟的防御策略和营造良好社会支持系统两方面对贫困生的心理健康进行维护。  相似文献   
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