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951.
BACKGROUND: Nosocomial bloodstream infections (NBSIs) occur frequently in neonatal intensive care units (NICUs) and are associated with substantial morbidity and mortality. Little has been published regarding variation in NBSI among institutions. OBJECTIVE: To determine NBSI incidence among six NICUs and to explore how much variation is explained by patient characteristics and NICU practice patterns. METHODS: From October, 1994, to June, 1996, six regional NICUs prospectively abstracted clinical records of all neonates weighing <1,500 g. Occurrence of NBSI, defined as first positive culture occurring >48 h after admission, was analyzed in relation to baseline patient characteristics and several common therapeutic interventions. Variables significant in univariate analyses were analyzed by Cox proportional hazards regression. RESULTS: There were 258 NBSIs (incidence, 19.1%) among 1,354 inborn first admissions. Incidence varied significantly by site, from 8.5 to 42%. Birth weight, Broviac catheter use and parenteral nutrition were significantly associated with NBSI (P < 0.05). When controlling for these variables interinstitutional variation in NBSI occurrence decreased but remained significant. CONCLUSIONS: Neonatal NBSI incidence varies substantially among institutions despite adjustment for length of stay and some known risk factors. The uses of Broviac catheters and especially intravenous nutrition supplements were significant determinants of NBSI risk.  相似文献   
952.
PURPOSE: Service quality, defined as patients' self-reported experience of care, is used as a metric for evaluating quality. Most studies rely on retrospective consumer surveys rather then more intensive data collection methods, possibly underestimating the incidence of service quality incidents. SUBJECTS AND METHODS: The objective of the study was to characterize patient-reported service quality deficiencies on a general medicine unit. We studied a cohort of 228 adult inpatients at a Boston teaching hospital. Investigators reviewed medical records and interviewed patients during the hospitalization and by telephone after discharge. Physician investigators classified patients' incident reports. We calculated the rate of service incidents, characterized incident types, and used multivariable Poisson and logistic regression models to examine factors associated with patient reporting and overall rating of the hospitalization. RESULTS: Eighty-eight (38.6%) of 228 patients experienced 157 service quality incidents during the admission, for a rate of 68.9 incidents per 100 admissions. The most common service quality problems involved waits and delays (n = 45), problems with communication between staff and patients (n = 36), and environmental issues and amenities (n = 35). In the multivariable analysis, men (IRR 1.6, 95% CI 1.1-2.2), patients covered by hospitalists (1.5, 1.1-2.2), and patients with more medication allergies (1.1 per allergy, 1.1-1.2) reported more service incidents; patients with Medicaid or free care reported fewer (0.5, 0.3-0.9). Patients with service quality incidents were more likely to describe the hospitalization as other than excellent (adjusted OR 1.8 per incident, 95% CI 1.3-2.5). CONCLUSION: Service quality deficiencies are common among medical inpatients, and are strongly associated with patients' dissatisfaction with the hospitalization.  相似文献   
953.
BACKGROUND: A large number of skin diseases, including atopic dermatitis and psoriasis, appear to be precipitated or exacerbated by psychological stress. Nevertheless, the specific pathogenic role of psychological stress remains unknown. In 3 different murine models of psychological stress, it was recently shown that psychological stress negatively impacts cutaneous permeability barrier function and that coadministration of tranquilizers blocks this stress-induced deterioration in barrier function. OBJECTIVES AND METHODS: The relationship between psychological stress and epidermal permeability barrier function was investigated in 27 medical, dental, and pharmacy students without coexistent skin disease. Their psychological state was assessed with 2 well-validated measures: the Perceived Stress Scale and the Profile of Mood States. Barrier function was assessed simultaneously with the stress measures at periods of presumed higher stress (during final examinations) and at 2 assumed, lower stress occasions (after return from winter vacation [approximately 4 weeks before final examinations] and during spring vacation [approximately 4 weeks after final examinations]). RESULTS: The subjects as a group demonstrated a decline in permeability barrier recovery kinetics after barrier disruption by cellophane tape stripping, in parallel with an increase in perceived psychological stress during the higher vs the initial lower stress occasions. During the follow-up, presumed lower stress period, the subjects again displayed lower perceived psychological stress scores and improved permeability barrier recovery kinetics, comparable to those during the initial lower stress period. Moreover, the greatest deterioration in barrier function occurred in those subjects who demonstrated the largest increases in perceived psychological stress. CONCLUSION: These studies provide the first link between psychological status and cutaneous function in humans and suggest a new pathophysiological paradigm, ie, stress-induced derangements in epidermal function as precipitators of inflammatory dermatoses.  相似文献   
954.
People with dementia often have painful conditions that go unnoticed because of their communication problems. Signs of pain in this population may include agitation and observable behaviors associated with discomfort. Agitation, discomfort, and severity of dementia were evaluated in 33 Veterans Affairs nursing home patients using the Cohen-Mansfield Agitation Inventory, the Discomfort Scale, and the Global Deterioration Scale, respectively. Findings revealed statistically significant positive relationships between agitation and severity of dementia (r = 0.34, P = 0.01), discomfort and severity of dementia (r = 0.44, P = 0.01), and agitation and discomfort (r = 0.50, P = 0.003). In a multiple regression analysis, agitation was significantly associated with discomfort (R(2) =.14, P = 0.02) after controlling for dementia severity. These preliminary findings suggest that discomfort may be a source of agitation.  相似文献   
955.
956.
BACKGROUND: n-3 Fatty acids (FAs) have been shown to be beneficial for cardiovascular health. Whether n-3 FAs from oily fish consumed weekly or from fish-oil capsules taken daily are equally bioavailable is not clear. OBJECTIVE: The purpose of this study was to compare the rate and extent of enrichment of blood cell membranes [ie, red blood cells (RBCs)] and plasma phospholipids with n-3 FAs from these 2 sources. DESIGN: Healthy premenopausal female volunteers were randomly assigned to consume a daily average of 485 mg eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids either from 2 servings of oily fish (ie, salmon and albacore tuna) per week or from 1-2 capsules/d. RESULTS: After 16 wk, EPA+DHA in RBCs in the fish group (n = 11) increased from 4.0 +/- 0.6% of total FAs to 6.2 +/- 1.4%, whereas it rose from 4.3 +/- 1.0% to 6.2 +/- 1.4% in the capsule group (P < 0.0001 for both; NS for group effect). Similar results were observed in plasma phospholipids. EPA+DHA stabilized in the latter after 4 wk but continued to rise through week 16 in RBCs. EPA in RBCs increased significantly (P = 0.01) more rapidly in the fish group than in the capsule group during the first 4 wk, but rates did not differ significantly between groups thereafter. Total FA variances were less in RBCs than in plasma phospholipids (P = 0.04). CONCLUSION: These findings suggest that the consumption of equal amounts of EPA and DHA from oily fish on a weekly basis or from fish-oil capsules on a daily basis is equally effective at enriching blood lipids with n-3 FAs.  相似文献   
957.
The inner medullary collecting duct (IMCD) has been proposed to be a site of atrial natriuretic factor (ANF) action. We carried out experiments in isolated perfused terminal IMCDs to determine whether ANF (rat ANF 1-28) affects either osmotic water permeability (Pf) or urea permeability. In the presence of a submaximally stimulating concentration of vasopressin (10(-11) M), ANF (100 nM) significantly reduced Pf by an average of 46%. Lower concentrations of ANF also significantly inhibited vasopressin-stimulated Pf by the following percentages: 0.01 nM ANF, 18%; 0.1 nM, 46%; 1 nM, 48%. Addition of exogenous cyclic GMP (0.1 mM) mimicked the effect of ANF, decreasing Pf by an average of 48%. ANF also inhibited cyclic AMP-stimulated Pf by an average of 31%. ANF did not affect urea permeability, nor did it alter vasopressin-stimulated cyclic AMP accumulation. We conclude that ANF at physiological concentrations causes a large inhibition of vasopressin-stimulated Pf in the rat terminal IMCD, and that cyclic GMP is the second messenger mediating the effect. ANF appears to act at a site distal to cyclic AMP generation in the chain of events linking vasopressin receptor binding to an increase in osmotic water permeability.  相似文献   
958.
BACKGROUND: In 1993, the American Association of Blood Banks (AABB) received reports of severe hypotensive reactions associated with platelet transfusions. The question arose as to whether these reports were indicative of a previously uncharacterized platelet transfusion reaction. STUDY DESIGN AND METHODS: To further characterize these reactions, the AABB Transfusion Practices Committee developed a series of three questionnaires. The initial questionnaire was sent to all AABB institutional members; the two subsequent questionnaires were sent to those institutions reporting severe and/or unusual platelet transfusion reactions. This report focuses on the 24 responses to the third and most detailed questionnaire, which specifically addressed reactions that were characterized by hypotension and/or unexplained respiratory failure. RESULTS: Of the 24 detailed responses received, 4 were not considered to represent unusual reactions to platelet transfusion, 3 described reactions consistent with a (presumably unrecognized) diagnosis of transfusion-related acute lung injury, and 17 described reactions that were primarily characterized by hypotension. The majority of the hypotensive reactions occurred within 1 hour of the beginning of the transfusion (88%), were associated with respiratory distress (82%), and resolved rapidly after cessation of the transfusion (82%). Eighty-eight percent of implicated components had been white cell reduced by filtration. CONCLUSION: The hypotensive platelet transfusion reactions that were described appear to represent a previously uncharacterized complication of platelet transfusion. However, the nature of the questionnaires used in this investigation does not allow the drawing of firm conclusions as to the frequency or the cause of these reactions.  相似文献   
959.
Background: During the storage of cellular components before transfusion, cytokines that may mediate transfusion reactions are released from white cells (WBCs). Adverse effects of transfused cellular blood components therefore depend not only on the number of residual WBCs in blood components, but also on the timing of WBC reduction. Study Design and Methods: Febrile nonhemolytic transfusion reactions (FNHTRs), allergic reactions, and other reactions were characterized in recipients of 4728 units of red cells (RBCs) and 3405 bags of single-donor apheresis platelets (SDAPs), all of which underwent prestorage WBC reduction. To delineate the impact of prestorage versus poststorage WBC reduction of RBCs on transfusion reactions, these results were compared with reactions occurring after the transfusion to similar recipients of 6447 bags of RBCs that underwent poststorage WBC reduction by bedside filtration and 5197 units of SDAPs that underwent prestorage WBC reduction. The levels of interleukin (IL) 1 beta, IL-6, IL-8, and tumor necrosis factor-alpha (TNF-alpha) were measured in a subset of 20 implicated cellular blood components at the time of transfusion reactions and correlated with the duration of storage before transfusion. Results: The incidence of reactions was greater after transfusions of SDAPs (5.49%) than of RBCs (1.63%). The incidence of FNHTRs after transfusion of RBCs that were WBC reduced before storage (1.1%) was significantly lower (p = 0.0045) than that after transfusion of RBCs that were WBC reduced after storage (2.15%). Although allergic reactions to RBCs that were WBC reduced before storage were also less common (0.41%) than those to RBCs that were WBC reduced after storage (0.51%), the difference was not significant (p = 0.067). At the time of reactions to RBCs and SDAPs that were reduced before storage, the level of IL-6 was negatively correlated (r = -0.54, p = 0.014) with the duration of storage before transfusion, and there was no correlation between the level of either IL-1 beta or IL-8 and the interval before transfusion. TNF-alpha was not detectable in any implicated component. Conclusion: FNHTRs, but not allergic reactions, were less common after transfusion of RBCs that were WBC reduced before storage than after the transfusion of those WBC reduced after storage at the bedside by filtration. The level of IL-6 in implicated cellular blood components that were WBC reduced before storage was inversely correlated with the length of storage before transfusion. Further studies are needed to determine whether the transfusion of cellular blood components that were WBC reduced before storage can both diminish the incidence of adverse reactions and improve outcome.  相似文献   
960.
A comparative study among college students of sexual abuse in childhood.   总被引:1,自引:0,他引:1  
A disproportionate random sample (200 women, 400 men) of students attending a major university was invited to participate in a mailed survey to study differences in self-efficacy, coping, and well-being between men and women who were sexually abused in childhood and those who were not. A total of 271 students (111 women, 160 men) responded by returning the completed survey. Fifty percent of the women and 22% of the men in the sample reported one or more unwanted sexual experiences in childhood. Multivariate analysis of variance (MANOVA) techniques to analyze differences in self-efficacy, coping (confrontive, emotive, palliative), and well-being between women and men who reported childhood sexual abuse and those who did not showed significant interaction effects by sex for abuse (F = 2.609, P = .025, df 5,263) and significant effects by sex (F = 3.356, P = .006), but no significant differences for abuse alone. Univariate F tests were significant (F = 5.386, P = .021) for palliative coping with abused men reporting the highest scores, abused and nonabused women having the highest scores on emotive coping (F = 9.049, P = .003), and nonabused men and women having highest scores on well-being (F = 7.276, P = .007). A second MANOVA was performed on data from 245 students (nonabused and those who reported contact sexual abuse). Significant interaction effects by sex for abuse (F = 2.259, P = 0.49, df 5,237) and main effects for abuse (F = 3.225, P = .008) were found. Although abused men scored lowest on well-being, both abused men and abused women scored higher on emotive coping and lower on well-being than nonabused subjects. These are new findings with implications for developing and testing nursing interventions for this vulnerable group of young adults.  相似文献   
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