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1.
Ischaemia-reperfusion injury (IRI) is of obvious relevance in situations where there is an interruption of blood supply to the gut, as in vascular surgery, or in the construction of free intestinal grafts. It is now appreciated that IRI also underlies the gut dysfunction that occurs in early shock, sepsis, and trauma. The events that occur during IRI are complex. However, recent advances in cellular biology have started to unravel these underlying processes. The aim of this review is to provide an outline of current knowledge on the mechanisms and consequences of IRI. Initially, IRI appears to be mediated by reactive oxygen metabolites and, at a later stage, by the priming and activation of polymorphonuclear neutrophils (PMN). Ischaemia-reperfusion injury can diminish the barrier function of the gut, and can promote an increase in the leakage of molecules (intestinal permeability) or the passage of microbes across the wall of the bowel (bacterial trans-location). Ischaemia-reperfusion injury to the gut can result in the generation of molecules that may also harm distant tissues.  相似文献   
2.
Can nurses practice caring within a healthcare system that promotes codependency? Caring promotes mutual empowerment of all participants while codependent caring disempowers. Nurses are expected to practice caring with clients, The authors contend, however, that nursing, as historically and currently practiced within bureaucratic/patriarchal organizations, is founded on a vlue system that fosters codependency. Until nursing is practiced within the context of caring organizations and a caring healthcare system, nurses will continue to be powerless to shape their own practice as carers and burnout will continue to be a problem.  相似文献   
3.
Nosocomial pressure ulcers (PU) occur in approximately 12% of all hospitalized patients. The risk can be determined by a variety of intrinsic and extrinsic factors. As a first line of defense against nosocomial PU, we use the Braden Scale to determine the potential risk of PU development during hospitalization. Once risk was identified, our standard was to implement an individualized plan of care. However, consistent implementation of PU preventative measures was lacking. As a result, a process improvement project was developed and implemented. The purpose of this process improvement project was to increase communication about and awareness of the need to vigorously intervene and document whenever there is risk of, or development of, a nosocomial PU. By initiating consistent use of a PU Tracking Form, developing unit-based wound champions that serve as experts in ulcer prevention, and creating an individual case analysis process, PU prevention and tracking was institutionalized. Results indicate that our nosocomial PU rate has declined from 7% to 4%.  相似文献   
4.
Most U.S. medical schools offer courses in the behavioral and social sciences (BSS), but their implementation is frequently impeded by problems. First, medical students often fail to perceive the relevance of the BSS for clinical practice. Second, the BSS are vaguely defined and the multiplicity of the topics that they include creates confusion about teaching priorities. Third, there is a lack of qualified teachers, because physicians may have received little or no instruction in the BSS, while behavioral and social scientists lack experience in clinical medicine. The authors propose an approach that may be useful in overcoming these problems and in shaping a BSS curriculum according to the institutional values of various medical schools. This approach originates from insights gathered during their attempts to teach various BSS topics at four Israeli medical schools. They suggest that medical faculties (1) adopt an integrative approach to learning the biomedical, behavioral, and social sciences using Engel's "biopsychosocial model" as a link between the BSS and clinical practice, (2) define a hierarchy of learning objectives and assign the highest priority to acquisition of clinically relevant skills, and (3) develop clinical role models through teacher training programs. This approach emphasizes the clinical relevance of the BSS, defines learning priorities, and promotes cooperation between clinical faculty and behavioral scientists.  相似文献   
5.

The aim of this study was to assess the influence of the canal curvature on the efficacy of sonically, ultrasonically, and laser-activated irrigation in removing a biofilm-mimicking hydrogel (BMH) from simulated canal irregularities. Transparent resin blocks containing a curved root canal (40° or 60°) were used as test models. A 4-mm groove at 1 mm from the apex was filled with BMH. Five different irrigation procedures were performed (n=20): needle irrigation (NI), EndoActivator (EA), Eddy, ultrasonically activated irrigation (UAI) (Irrisafe), and laser-activated irrigation (LAI) using a pulsed erbium laser (PIPS approach). All protocols were executed for 3×20s. Images of the groove were taken before and after irrigation, and the percentage BMH removal was calculated using image analysis software. In the 40° canal curvature model, the highest BMH removal was observed for UAI (99.9%), yielding a significantly better removal than that of EA (57.2%) and NI (53.8%), but not of LAI (96.8%) and Eddy (99.4%). In the 60° canal curvature model, UAI removed 99.5%, which resulted in significantly greater hydrogel removal than all other groups (P < 0.05). The difference between LAI (82.5%) and Eddy (78.1%) was not statistically significant, but both were more effective than EA (13.5%) and NI (7.3%). Canal curvature negatively affects the cleaning efficacy of different irrigation methods. The effect was most pronounced for the sonic techniques, while this was not the case for UAI. This could be ascribed to the prebent ultrasonic tip. Despite the position of the laser tip at the orifice level, fluid streaming during LAI resulted in substantial BMH removal beyond the curve.

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6.
The utility of pharmacy claims data in detecting improper medication use, medication changes, and formulary adherence was assessed. Pharmacists provided six months of pharmacy claims data to primary care physicians for patients on the day of their scheduled clinic appointments. Similar data, not supplied to physicians, were generated for a matched population of patients on the day of their scheduled clinic appointments. A blinded pharmacist abstracter reviewed dictated office notes for both control and treatment groups. Medication adherence and medication changes were assessed by the abstracter as well as the difference in total medication costs for each of the groups before and after the pharmacy claims data were supplied. Surveys were distributed to physicians to determine whether pharmaceutical care was improved by the pharmacy claims data. In the treatment group, physicians detected medication nonadherence in 30.5% of their patients, while the abstracter noted nonadherence in 58.1% of patients. Physicians failed to detect any nonadherence in the control group, but the abstractor detected nonadherence in 57.1% of these patients. Changes in medication regimens occurred more often in the treatment group (p < 0.001). The mean percentage of patients switched to formulary agents significantly differed between the treatment and control groups (27.7% versus 0.0%, respectively) (p < 0.001). There were no differences in median drug costs for either group before or after the pharmacy claims data were provided. Provision of pharmacy claims data to physicians helped them detect medication nonadherence, evaluate therapeutic duplication or omissions, increase formulary use, and reduce the time required to obtain an accurate medication history.  相似文献   
7.
PURPOSE: To determine the feasibility, toxicity, and immunologic effects of vaccination with autologous tumor cells retrovirally transduced with the GM-CSF gene, we performed a phase I/II vaccination study in stage IV metastatic melanoma patients. PATIENTS AND METHODS: Sixty-four patients were randomly assigned to receive three vaccinations of high-dose or low-dose tumor cells at 3-week intervals. Tumor cell vaccine preparation succeeded for 56 patients (88%), but because of progressive disease, the well-tolerated vaccination was completed in only 28 patients. We analyzed the priming of T cells against melanoma antigens, MART-1, tyrosinase, gp100, MAGE-A1, and MAGE-A3 using human leukocyte antigen/peptide tetramers and functional assays. RESULTS: The high-dose vaccination induced the infiltration of T cells into the tumor tissue. Three of 14 patients receiving the high-dose vaccine showed an increase in MART-1- or gp100-specific T cells in the peripheral blood during vaccination. Six patients experienced disease-free survival for more than 5 years, and two of these patients developed vitiligo at multiple sites after vaccination. MART-1- and gp100-specific T cells were found infiltrating in vitiligo skin. Upon vaccination, the T cells acquired an effector phenotype and produced interferon-gamma on specific antigenic stimulation. CONCLUSION: We conclude that vaccination with GM-CSF-transduced autologous tumor cells has limited toxicity and can enhance T-cell activation against melanocyte differentiation antigens, which can lead to vitiligo. Whether the induction of autoimmune vitiligo may prolong disease-free survival of metastatic melanoma patients who are surgically rendered as having no evidence of disease before vaccination is worthy of further investigation.  相似文献   
8.
Parents play a critical role in shaping their children’s substance use behaviors, yet few studies have examined the messages that caregivers give their adolescents about tobacco. In this study, we identify tobacco-related messages discussed by African American maternal caregivers and their adolescent daughters. Twenty-five African American maternal caregivers and their adolescent daughters participated in a video-taped discussion about tobacco. Discussions were transcribed and coded thematically. Seven themes emerged, which were grouped into tobacco-messages and communication strategies. Messages included health risks, non-health-related reasons to stop smoking, reasons people smoke, and tobacco products and marijuana. Strategies caregivers used to communicate their tobacco-related messages included sharing personal or their families’ experience with smoking, using humor, and role-playing. Finally, embedded within all of the themes, participants expressed their disapproval of tobacco use, whether it was directed at their own use, their adolescents’ use, a family members’ use, or peers’ use. African American maternal caregivers and their daughters openly talk about a variety of tobacco-related topics, and caregivers are open to sharing their own and their families’ experience with substance use. Findings also suggest that having caregivers and their adolescents participate in discussions tasks could be potentially beneficial in facilitating discussions and could identify areas in which caregivers could use help in discussing sensitive topics.  相似文献   
9.
10.
OBJECTIVES: To determine how unmet needs for activity of daily living tasks influenced nursing home placement, death, or loss to follow-up in dementia. DESIGN: An 18-month longitudinal design, with interviews administered every 6 months. SETTING: Eight catchment areas in the United States. PARTICIPANTS: Five thousand eight hundred thirty-one dementia patients and their caregivers were included at baseline. MEASUREMENTS: Measures of sociodemographic context of care; functional, cognitive, and behavioral status of care recipients; caregiver stress and well-being; and formal and informal resources served as covariates. The independent variables of interest were unweighted unmet care need scores and unmet need scores weighted by importance and severity in a prior sample of older consumers of long-term care. Outcomes included nursing home placement, death, and loss to follow-up. RESULTS: Cox regression models suggested that greater unmet need was predictive of nursing home placement, death, and loss to follow-up. These results were apparent when the unweighted and the weighted scores for unmet need with activity of daily living dependencies were used. CONCLUSION: Unmet need may be useful in identifying dementia care recipients at risk for nursing home placement and death. Further study of unmet need is needed to effectively assess and target intervention protocols during the course of dementia.  相似文献   
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