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71.
Maximum effort flow-static recoil curves were obtained in 5 healthy subjects breathing air, He/O2, and SF6/O2 mixtures. In 4 of them maximum effort flows corresponded to really maximal flows and their curves were transformed into compliance curves for the flow limiting segments of the airway and analyzed from the point of view of a previously presented lung model (Pedersen and Nielsen 1976). The results showed, that viscosity dependent pressure losses from the alveoli to the flow limiting segments were minimal for air and SF6/O2, but not for He/O2. When viscosity dependent pressure losses could be neglected, then expiration of gases of different densities gave almost identical compliance curves for the flow limiting segments. This supported the applicability of the model. The calculated compliance curves for the flow limiting segments were compared with data from the literature, and the findings indicated that flow limitation during expirations with just maximal flows throughout began in the extrapulmonary airways and moved upstream during the expiration.  相似文献   
72.
The mechanical impedance of the ankle joint during electrical stimulation of the soleus is studied by applying constant-velocity 10° angular perturbations to the ankle and measuring the resultant torque. Both neurologically intact subjects and spinal cord injured subjects are tested. Lumped, piecewise linear models are developed to predict the torque from the measured displacement and acceleration signals. The commonly used second-order mass-spring-dashpot model fails to predict the changes in torque that occur following imposed movements. A fiveelement, directionally-dependent piecewise linear model is much better at predicting the measured responses for velocities up to 50° s−1. Numerical least squared error indentification techniques are used to estimate the model parameters for three neurologically intact and three spinal cord injured subjects. The average error between the model’s response and the measured response across all subjects is 10·9%. There is some evidence that a velocity-dependent non-linear model could produce better results than the directionally-dependent piecewise linear model.  相似文献   
73.
This paper addresses an evaluation of an administrative decision to change the manner in which services were paid for at a Student Health Center (SHC). The impact of the change in payment was observed through monitoring the number of scheduled appointments at the SHC which the patient failed to attend, reschedule, or cancel. The impact was assessed through a comparison of the weekly no-show rates from the year prior to the change in payment practices through the year following the change. A time-series statistical package was used to analyze the no-show data. Collateral measures on the number of students attending the university, staff opinions, and usage of the SHC by different student groups were collected. Evaluations of the impact of administrative decisions on health-related behavior were discussed, in addition to a discussion of the usefulness of time-series models for this type of evaluation.  相似文献   
74.
The relationship between the arterial blood pressure and the volume of the arteries within a segment of an extremity is nonlinear. The present paper shows how the flow and volume pulsations of the arteries within a limb segment can be simulated taking this property into account. An electrical model was constructed comprising one resistor and two voltage dependent ‘capacitors’, the latter corresponding to the pressure dependent elasticity, or compliance, of the arteries. Adequate simulations were obtained over a wide pressure range, which is impossible with linear models. The nonlinear, i.e. pressure dependent, relationship between the volume and pressure of arteries, observed under static conditions, must also be taken into consideration when studying pulsatile events with models whether mathematical or physical.  相似文献   
75.
精神专科医院门诊抑郁症患者服药依从性影响因素分析   总被引:5,自引:0,他引:5  
目的:探讨影响抑郁症患者服药依从性的影响因素.方法:选取2007年5月至10月于北京大学第六医院及北京回龙观医院门诊就诊的123例抑郁症患者,采用自编抑郁症患者就诊状况及服药依从性调查问卷进行调查,内容包括患者一般情况、患病及就诊情况调查、抑郁症发病次数、巩固治疗期坚持服药时间知晓情况及实际服药情况等.分别采用卡方检验及多元Logistic回归分析,探讨上述各因素与服药依从性的相关性.结果:完全依从组(完全按照医嘱时间和剂量服药的患者)和部分依从组(部分按照医嘱时间和剂量服药的患者)在医疗费用支付形式、病程、家属态度、抑郁症阳性家族史、对疾病性质的认识、就诊模式、第一主诉、患病次数、坚持服药时间知晓情况、家庭平均月收入等方面的差异有统计学意义(P<0.05),将患者服药依从情况作为因变量,将以上项目作为自变量进行Logistic回归,结果显示月收入、对疾病性质的认识、家属态度、就诊模式、医药费支付形式、病程进入回归方程,各变量比值比分别为:10.932、9.604、7.246、6.019、2.611、0.209.结论:抑郁症患者服药依从性与多方面因素相关,对疾病性质的认识、家属态度、就诊模式、医药费支付形式、病程、家庭平均月收入等是影响抑郁症患者服药依从性的重要因素.  相似文献   
76.
This cross‐sectional study identified variables associated with protease inhibitor (PI) non‐adherence in 179 patients taking anti‐retroviral therapy. Univariate analyses identified 11 variables associated with PI non‐adherence. Multiple logistic regression modelling identified three predictors of PI non‐adherence: low adherence self‐efficacy and seriousness of non‐adherence and HIV (p < .001), perceived absence of HIV associated illness (p < .01), and use of more than one type of recreational drug (p = .001). The model correctly classified 83.9% of the sample, offers psychologists insight into psychological barriers to treatment adherence to guide interventions for improving adherence, and supports a modified version of the reformulated health belief model.  相似文献   
77.
The relationships between the epidural pressures following the injection of local anesthetic solution and the spread of epidural analgesia were investigated. In 46 patients, 15ml of 2% mepivacaine was injected into the lumbar epidural space at a constant rate (1ml/sec) using an electropowered syringe pump. Injection pressures and residual pressures were recorded and the spread of analgesia to pinprick was assessed. The changes of the epidural pressures during and following the injection of a volume of local anesthetic solution in old subjects were significantly smaller than those in young subjects (P < 0.05). The spread of analgesia closely correlated with the epidural pressures during and following the injection of local anesthetic solution. The most close correlation was found between the epidural pressure immediately after the completion of injection and the spread of analgesia (r = –0.5659, P < 0.001). In conclusion, the lower the terminal injection pressure and the residual pressures associated with higher age, the wider the spread of epidural analgesia.(Hirabayashi Y, Matsuda I, Inoue S et al.: Epidural pressure and its relation to spread of epidural analgesia. J Anesth 1: 168–172, 1987)  相似文献   
78.
目的 为了解北京市东城区美沙酮维持治疗患者的依从性及其影响因素,为临床建立合理的治疗模式以及干预措施提供科学依据。方法 采用动态队列研究设计,研究起点为首次入组治疗的患者在美沙酮维持治疗门诊首次接受治疗的时间,终点为2021年4月30日。使用寿命表法分析维持治疗情况;利用COX比例风险模型分析患者依从性的影响因素。结果 共有331名患者进入本次研究。截至随访终点,累积发生脱失210例,脱失比例为63.44%。维持治疗时间中位数为5.33年。患者1、2、5年的累积维持治疗比例和维持治疗人年数分别为77.05%、67.67%、52.41%和279.00、234.50、170.00人年。COX比例风险模型分析结果显示:入组时年龄<50岁(HR=1.825,95%CI:1.087~3.062)、有职业(HR=1.515,95%CI:1.037~2.213)、日服药剂量<60 mg/d(HR=2.025,95%CI:1.380~2.972)、接受过强制隔离戒毒(HR=2.617,95%CI:1.345~5.092)是降低患者依从性的危险因素。结论 日服药剂量、职业、入组时年龄、是否接受过强制隔离戒毒是北京市东城区美沙酮维持治疗门诊患者依从性的影响因素。日服药剂量的减少有可能导致患者的依从性下降,最终影响治疗效果,因此门诊医生在降低患者的服药剂量时应慎重。  相似文献   
79.
目的 探讨基于微信平台的健康教育对社区精神分裂症患者服药依从性、精神症状及再住院率的影响。方法 通过简单随机抽样的方法从上海市虹口区精神卫生信息管理系统中选取160例社区精神分裂症患者,按随机数字表法分为观察组和对照组。对照组给予常规健康教育干预,观察组在常规健康教育干预的基础上,实施微信健康教育干预。分别在干预前(入组时)、干预6个月及12个月,对两组患者的药物依从性量表(medication adherence rating scale, MARS)和阳性与阴性症状量表 (positive and negative symptom scale, PANSS)的评分及再住院率进行比较,以t检验或χ2检验进行统计分析。结果 160例患者中观察组和对照组各80例,干预前两组患者MARS和PANSS评分差异无统计学意义(P>0.05),干预6个月和12个月时,观察组患者MARS评分均高于对照组[(6.84±2.68) vs (5.90±2.16)和(7.26±2.33) vs (5.97±1.77)]、PANSS评分均低于对照组[(46.33±7.50) vs (50.52±6.74)和(44.09±7.93) vs (50.03±6.59)],差异有统计学意义(P<0.05),干预12个月,观察组患者再住院率为2.50%低于对照组11.25%,差异有统计学意义(P<0.05)。结论 基于微信平台的健康教育能够提高社区精神分裂症患者服药依从性、改善精神症状和降低再住院率,值得社区推广使用。  相似文献   
80.
Relational continuity of care (COC) is becoming an important concept related to improving healthcare quality, reducing medical costs and increasing patient satisfaction with primary care. While community pharmacy (CP) has a considerable role in primary care, there are few reports dedicated to the role of relational COC in CP. This study reviewed the existing evidence of relational COC in CP and its effect on patients. PubMed, Embase, CINAHL, Cochrane Library CENTRAL and Google Scholar were used to search for relevant studies from the date of database inception through to January 2021, which were appraised according to eligibility criteria. There were no limitations on the primary outcome or language. Case reports and studies without control groups were excluded. The Newcastle–Ottawa quality assessment scale was used to assess the quality of the studies. Database searches identified 13 records. Relational COC measures in the included studies were grouped in three kinds; pharmacy-visiting pattern, Continuity of Care Index and loyalty. The assessed outcomes were medication adherence behaviour (e.g., the proportion of days covered, medication possession ratio), adverse drug reactions, potentially inappropriate drug prescribing and clinical outcomes. The odds of patients adhering to their medication regimen were about 1.1~2.5 times higher among those who consistently visited a single pharmacy compared to patients visiting multiple pharmacies. Additionally, the care provision with a high level of relational continuity could lower inappropriate drug use by 21~32 per cent and the use of other costly services by 12~29 per cent. This study suggests that a high degree of relational COC in CP could improve safe use of medications among patients. Future research is needed to employ more rigorous methods to reduce heterogeneity and to measure effects on clinical outcomes.  相似文献   
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