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Abstract: Adequate venous access is an essential component of therapeutic plasma exchange (TPEX). The simplest kind of venous access is venipuncture of antecubital veins, but this technique may be limited by venous size or scarring following the procedure, requiring the placement of a specialized vascular access device (VAD). VADs provide reliable central venous access and may remain in place for several weeks or months, depending on the VAD and the venous site chosen. Their use, however, is potentially limited by the risk of complications. We discuss indications for insertion, choice of catheter and access site, and complications of VAD placement for TPEX.  相似文献   
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Development of interventions to prevent accidental occupational fatalities requires the prior identification of those at risk and the circumstances surrounding the injuries. A survey of unintentional farm fatalities was conducted using medical examiner reports (RIME) and death certificates (MECD) to identify deaths due to agricultural occupational injuries in North Carolina from 1984 through 1988. Of 393 cases, 123 met the criteria "farmer" listed as occupation on the RIME/MECD and/or "victim" in a rural area performing a farming task when injured. A second aim of this study was to use an existing data base to achieve maximum accuracy in identifying true cases of work-related farm fatalities.
A fatality rate of 41/100,000 agricultural workers was found; the National Institutes of Occupational Safety and Health's National Traumatic Occupational Fatality study criteria would have identified only 57 percent of these. Victims were characterized as middle age (53 years), white (76%), male (100%), full-time farmers (65%). Injury occurred during harvest season on Monday or Tuesday (47%) between 2 and 6 p.m. (54%). Death was pronounced at the scene (74%), with probable cause listed as tractor (62%). Injury location and land elevation were also related, with the mountain region having twice the fatality rate as the coastal plains region.  相似文献   
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Hispanics are a growing ethnic minority in the United States and one at significant risk for heart failure. Health-related quality of life (HRQL) is poor in individuals with heart failure, especially during and immediately following hospitalization. No prior research into the HRQL of Hispanics with heart failure was located. A sample of 80 individuals with heart failure, evenly divided by primary language and matched on functional status using the New York Heart Association classification system and age, was studied for 6 months following hospital discharge. Data on HRQL were collected using Spanish and English versions of the Minnesota Living with Heart Failure Questionnaire. Scores improved over time in both groups but significantly more so in the Hispanics when compared to the non-Hispanics. Group differences in HRQL could not be explained by demographics, clinical characteristics, treatment received, perceived support, or instrument response characteristics. Further exploration of this naturally occurring phenomenon may provide insight into how HRQL can be improved in the general heart failure population.  相似文献   
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This article explores the relationship of ethics to validity in hermeneutic phenomenological inquiry. First, the authors present a brief overview of the various discourses on validity in qualitative research that have been variously applied to hermeneutic phenomenological inquiry. Next, they examine how relational ethics is a presence to bear within this form of inquiry. Finally, they offer a set of ethical reflections to help the researcher engage in a process of ethical questioning during each step of the research process.  相似文献   
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OBJECTIVE: There is a high comorbidity between symptoms of post-traumatic stress disorder (PTSD) and chronic pain incidence. The objective of this investigation was to determine the prevalence of PTSD symptoms in chronic orofacial pain patients. STUDY DESIGN: The study included 1478 adult patients (mean age 36.4 +/- 12.7 years) with primary diagnoses of masticatory/cervical muscle pain or temporomandibular joint pain. Patients completed a battery of psychometric questionnaires including a screening for PTSD symptoms. The sample was divided into a PTSD-positive group (n=218, 15%) a PTSD-negative group (n=551, 37%), and a no-stressor group (n=709, 48%) according to stressor incidence and symptom severity. RESULTS: The current prevalence of PTSD symptomatology was considerably higher than that reported in surveys from the general population. Patients in the PTSD-positive symptom group reported significantly higher psychological distress, sleep dysfunction, and pain severity compared to patients in the other groups. Psychological distress as measured by the SCL-90-R reached clinically significant levels only in those patients with PTSD symptomatology. CONCLUSIONS: The results of this study performed at a tertiary care center suggest that TMD patients without PTSD symptomatology show low levels of psychological distress, if any. Clinically significant levels of psychological distress are likely indicators for PTSD. PTSD screening should be included as part of a routine psychometric test battery in TMD patients.  相似文献   
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Cognitive theory holds that dysfunctionalattitudes are important risk factors for depression.Critics have questioned this view, noting that, althoughdysfunctional attitudes are elevated in depression, they are not evident in vulnerable individualswho are asymptomatic. To deal with this criticism,Miranda and Persons (1988) have advanced the mood-statedependent hypothesis, which suggests that cognitive vulnerability factors are indeed present invulnerable individuals, but remain dormant untilactivated by negative mood. To test this hypothesis, 33women with and 67 women without histories of depression reported dysfunctional attitudes before andafter a film negative mood induction. As predicted,vulnerable subjects who reported increased negative moodreported increased dysfunctional attitudes.Unexpectedly, nonvulnerable subjects who reported increasednegative mood reported decreased dysfunctionalattitudes. These findings support the mood-statedependent hypothesis, and suggest that a deficit in theability to regulate negative emotions may be animportant feature of vulnerability todepression.  相似文献   
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