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121.
J Quan  M Wadsworth 《AAOHN journal》2000,48(10):461-469
1. Providing bereavement support for grieving employees can positively impact their adjustment and productivity. 2. Good bereavement care follows the nursing process approach: assessment, analysis, planning (goal setting), intervention/implementation, and evaluation. It acknowledges the five dimension of optimal health, and incorporates them into the nursing process. 3. The occupational health nurse, as clinician and advisor, can provide care to the bereaved individual and guidance to the manager and coworkers about the grief process and how to interact with the grieving employee. 4. Grief work is necessary for healing. The occupational health nurse can play a valuable role in facilitating the work by offering clinical support, a "safe" place for the grieving employee to talk about the death, referrals to the Employee Assistance Program or other professional support, and education about the process.  相似文献   
122.
Superoxide in the pulmonary circulation   总被引:14,自引:0,他引:14  
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123.
The purpose of this study was to investigate differences in selected biomechanical and physiological measurements and subjective preferences for ambulation with the standard single-tip axillary crutch versus the rocker-bottom-type axillary crutch. Self-selected walking velocities (S-SWVs) and stride length for each crutch type were determined for a two-point, non-weight-bearing, swing-through gait in 24 healthy volunteers. Relative exercise intensity, oxygen uptake (VO2), and gait efficiency were assessed for each crutch type at both S-SWVs. Subjects negotiated two architectural barriers (stairs and ramp) and completed a subjective questionnaire concerning crutch preferences. Walking with either crutch type resulted in slower S-SWVs, greater VO2, higher relative exercise intensity, and reduced gait efficiency compared with values for normal unassisted ambulation. An analysis of variance for these variables revealed nonsignificant between-crutch differences. Based on the subjective data, a preference for the standard single-tip crutch was evident. Within the scope of the study, the results supported no apparent advantage relative to energy expenditure to using the rocker-bottom crutch.  相似文献   
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125.
The mechanism for consumption of terminal complement components and release of bound components from the surface of serum-resistant salmonella minnesota S218 was studied. Consumption of C8 and C9 by S218 occurred through interaction with C5b67 on the bacterial surface because C8 and C9 were consumed when added to S218 organisms previously incubated in C8-deficient serum and washed to remove all C5b67 on the bacterial surface because C8 and C9 were consumed when added to S218 organisms previously incubated in C8- deficient serum and washed to remove al but cell bound C5b67. Rapid release of (125)I C5 and (125)I C7 from the membrane of S218 was dependent on binding of C8 because (125)I C5 and (125)I C7 deposition in C8D serum was stable and was twofold higher in C8D than in PNHA, and addition of purified C8 or C8 and C9 to S218 previously incubated in C8D serum caused rapid release of (125)I C5 and (125)I C7 from the organism. Analysis by sucrose density gradient ultracentrifugation of the fluid phase from the reaction of S218 and 10 percent PNHS revealed a peak consistent with SC5b-9, in which the C9:C7 ratio was 3.3:1, but the NaDOC extracted bound C5b-9 complex sedimented as a broad peak with C9:C7 of less than 1.2:1. Progressive elution of C5b67 and C5b-9 from S218 but not serum-sensitive S. minnesota Re595 was observed with incubation in buffers of increasing ionic strength. Greater than 90 percent of the bound counts of (125)I C5 or (125)I C9 were released from S218 by incubation in 0.1 percent trypsin, but only 57 percent of (125)I C9 were released by treatment of Re595 with trypsin. These results are consistent with the concept that C5b-9 forms on the surface of the serum-sensitive S. minnesota S218 in normal human serum, but the formed complex is released and is not bactericidal for S218 because it fails to insert into hydrophobic outer membrane domains.  相似文献   
126.
127.
Recombinant adenoviruses are currently being used as vectors for gene delivery to a wide variety of cells and tissues. Although generally efficacious for gene transfer in vitro, improvement in the efficiency of vector delivery in vivo may aid several gene therapy applications. One major obstacle is the lack of high-affinity viral receptors on the surface of certain cells that are targets for gene therapy. In principle, incorporation of avid, cell-specific ligands into the virion could markedly improve vector entry into the desired tissues. We have developed a strategy for addressing this issue in the lung by biopanning differentiated, ciliated airway epithelial cells against a phage display library. The peptide with the most effective binding was coupled to the surface of an adenovirus using bifunctional polyethylene glycol (PEG) molecules. The chemically modified adenoviral vector was able to effect gene transfer to well-differentiated human airway epithelial cells by an alternative pathway dependent on the incorporated peptide. Coupling of PEG to the surface of the virus also served to partially protect the virus from neutralizing antibodies in vitro. These experiments will aid in the design of improved adenoviral vectors with the capacity for more specific and efficient delivery of therapeutic genes to desired target tissues. We have used a novel method for enhancing gene delivery to target cells by coupling a biologically selected peptide to the surface of an adenovirus with bifunctional PEG molecules. Modification of the viral capsid by the addition of a peptide with binding preference for differentiated ciliated airway epithelia allowed gene delivery to those cells by a novel entry pathway. Incorporation of the CFTR gene in a similarly modified vector resulted in correction of defective Cl- transport in well-differentiated epithelial cultures established from human cystic fibrosis (CF) donors. The presence of PEG molecules on the surface of the virus served, in addition, to reduce antibody neutralization. Modification of adenoviruses with PEG/peptide complexes can serve to partially overcome the barrier of inefficient gene transfer in some cell types and some of the adverse immunological responses associated with gene delivery by these vectors.  相似文献   
128.
Glucagon-like peptide 1 (GLP-1) is a promising candidate for the treatment of type II diabetes. However, the short in vivo half-life of GLP-1 has made peptide-based treatments challenging. Gene therapy aimed at achieving continuous GLP-1 expression presents one way to circumvent the rapid turnover of GLP-1. We have created a GLP-1 minigene that can direct the secretion of active GLP-1 (amino acids 7-37). Plasmid and adenoviral expression vectors encoding the 31-amino-acid peptide linked to leader sequences required for secretion of GLP-1 yielded sustained levels of active GLP-1 that were significantly greater than endogenous levels. Systemic administration of expression vectors to animals using two diabetic rodent models, db/db mice and Zucker Diabetic Fatty (ZDF) rats, yielded elevated GLP-1 levels that lowered both the fasting and random-fed hyperglycemia present in these animals. Because the insulinotropic actions of GLP-1 are glucose dependent, no evidence of hypoglycemia was observed. Improved glucose homeostasis was demonstrated by improvements in %HbA1c (glycated hemoglobin) and in glucose tolerance tests. GLP-1-treated animals had higher circulating insulin levels and increased insulin immunostaining of pancreatic sections. GLP-1-treated ZDF rats showed diminished food intake and, in the first few weeks following vector administration, a diminished weight gain. These results demonstrate the feasibility of gene therapy for type II diabetes using GLP-1 expression vectors.  相似文献   
129.
The renal excretion of water, electrolytes, aldosterone and kallikrein was monitored in 12 ileostomized patients before and during sodium deprivation. Changes in plasma renin activity (PRA), plasma aldosterone and plasma arginine vasopressin (AVP) concentrations were measured, together with aldosterone in ileal fluid. The pattern of gut peptide release in response to a test meal was also examined to assess whether a circulating gut peptide might be involved in the renal adaptation to sodium restriction, and compared with healthy normal subjects who were under no dietary constraint. In each patient renal sodium excretion fell within 8-12 h of sodium deprivation and was associated with a prompt and significant rise in PRA; much later increases in plasma aldosterone concentration and renal aldosterone excretion occurred, and were established by day 2 of sodium restriction. No consistent change in renal kallikrein excretion was found. Ileal sodium loss was little changed by sodium deprivation, but ileal potassium concentration rose steadily and became significantly correlated with PRA, and to a lesser extent with renal aldosterone excretion. Of the gut peptides measured in plasma, only the insulin profile was altered by sodium deprivation, with an increase in the test meal response; insulin has previously been shown to have a significant antinatriuretic action at physiological concentrations. Plasma levels of pancreatic polypeptide and motilin were increased in ileostomized patients when compared with normal subjects, but were unaffected by the change to a low sodium diet. An early increase in urine flow and water diuresis occurred during sodium deprivation, following a cyclical pattern with peaks each evening.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
130.
Since 9/11, military service in the United States has been characterized by wartime deployments and reintegration challenges that contribute to a context of stress for military families. Research indicates the negative impact of wartime deployment on the well being of service members, military spouses, and children. Yet, few studies have considered how parental deployments may affect adjustment in young children and their families. Using deployment records and parent-reported measures from primary caregiving (N = 680) and military (n = 310) parents, we examined the influence of deployment on adjustment in military families with children ages 0–10 years. Greater deployment exposure was related to impaired family functioning and marital instability. Parental depressive and posttraumatic stress symptoms were associated with impairments in social emotional adjustment in young children, increased anxiety in early childhood, and adjustment problems in school-age children. Conversely, parental sensitivity was associated with improved social and emotional outcomes across childhood. These findings provide guidance to developing preventive approaches for military families with young children.  相似文献   
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