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991.
Mittal V Rosen J Govind R Degenholtz H Shingala S Hulland S Rhee Y Kastango KB Mulsant BH Castle N Rubin FH Nace D 《The Gerontologist》2007,47(2):159-168
PURPOSE: Several studies have previously documented the existence of a perception gap-the extent to which quality-of-life ratings provided by nursing home residents and caregivers diverge. In this study we use Helson's adaptation-level theory to investigate three types of antecedents: (a) focal factors, (b) background factors, and (c) residual factors. DESIGN AND METHODS: We calculated the perception gap for 11 quality-of-life domains. Caregivers rated both job satisfaction and their perception of quality of life of residents in the unit where they provided service. Concurrently, residents from these units completed quality-of-life interviews. We computed the perception gap by subtracting the residents' ratings from the caregivers' ratings for each quality-of-life domain. We conducted a hierarchical linear model using 3,850 observations to predict the perception gap. RESULTS: Caregivers perceive quality of life to be lower than residents do across all domains fairly consistently. Caregiver demographics do not directly predict the perception gap. However, satisfaction with work, pay, and promotion were significant predictors (p <.05), and satisfaction with supervisor was a marginally significant predictor (p <.10), of the perception gap. As satisfaction with these job dimensions increased, the perception gap decreased. Additional models show that several caregiver demographics directly influence job-satisfaction dimensions, though they did not influence the perception gap. IMPLICATIONS: Job-satisfaction dimensions, rather than caregiver characteristics, are the appropriate predictors of the perception gap. However, caregiver demographics exert their influence indirectly by means of job satisfaction. A key finding is that higher job satisfaction leads to a smaller perception gap. Helson's adaptation-level theory appears to be a useful approach for understanding the antecedents of the perception gap. 相似文献
992.
993.
Breen KM Oakley AE Pytiak AV Tilbrook AJ Wagenmaker ER Karsch FJ 《Endocrinology》2007,148(4):1882-1890
This study assessed the importance of cortisol in mediating inhibition of pulsatile LH secretion in sheep exposed to a psychosocial stress. First, we developed an acute psychosocial stress model that involves sequential layering of novel stressors over 3-4 h. This layered-stress paradigm robustly activated the hypothalamic-pituitary-adrenal axis and unambiguously inhibited pulsatile LH secretion. We next used this paradigm to test the hypothesis that cortisol, acting via the type II glucocorticoid receptor (GR), mediates stress-induced suppression of pulsatile LH secretion. Our approach was to determine whether an antagonist of the type II GR (RU486) reverses inhibition of LH pulsatility in response to the layered stress. We used two animal models to assess different aspects of LH pulse regulation. With the first model (ovariectomized ewe), LH pulse characteristics could vary as a function of both altered GnRH pulses and pituitary responsiveness to GnRH. In this case, antagonism of the type II GR did not prevent stress-induced inhibition of pulsatile LH secretion. With the second model (pituitary-clamped ovariectomized ewe), pulsatile GnRH input to the pituitary was fixed to enable assessment of stress effects specifically at the pituitary level. In this case, the layered stress inhibited pituitary responsiveness to GnRH and antagonism of the type II GR reversed the effect. Collectively, these findings indicate acute psychosocial stress inhibits pulsatile LH secretion, at least in part, by reducing pituitary responsiveness to GnRH. Cortisol, acting via the type II GR, is an obligatory mediator of this effect. However, under conditions in which GnRH input to the pituitary is not clamped, antagonism of the type II GR does not prevent stress-induced inhibition of LH pulsatility, implicating an additional pathway of suppression that is independent of cortisol acting via this receptor. 相似文献
994.
995.
Bloomfield SF Cookson B Falkiner F Griffith C Cleary V 《American journal of infection control》2007,35(2):86-88
Although health care-associated methicillin resistant staphylococcus aureus and clostridium difficile strains are primarily a risk to hospital patients, people are increasingly concerned about their potential to circulate in the community and the home. They are thus looking for support in order to understand the extent of the risk, and guidance on how to deal with situations where preventing infection from these species becomes their responsibility. A further concern are the community-acquired MRSA and C. difficile strains, and other antibiotic resistant strains circulating in the community such as the Extended-spectrum beta-lactamase (ESBL) Escherichia coli. In response to concerns about such organisms in the community, the International Scientific Forum on Home Hygiene has produced a report evaluating MRSA, C. difficile, and ESBL-producing E. coli from a community viewpoint. The report summarizes what is known about their prevalence in the community, their mode of transmission in the home, and the extent to which they represent a risk. It also includes "advice sheets" giving practical guidance on what to do when there is a risk of infection transmission in the home. 相似文献
996.
de la Fuente MA Sasahara Y Calamito M Antón IM Elkhal A Gallego MD Suresh K Siminovitch K Ochs HD Anderson KC Rosen FS Geha RS Ramesh N 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(3):926-931
Wiskott-Aldrich syndrome protein (WASP) is in a complex with WASP-interacting protein (WIP). WASP levels, but not mRNA levels, were severely diminished in T cells from WIP(-/-) mice and were increased by introduction of WIP in these cells. The WASP binding domain of WIP was shown to protect WASP from degradation by calpain in vitro. Treatment with the proteasome inhibitors MG132 and bortezomib increased WASP levels in T cells from WIP(-/-) mice and in T and B lymphocytes from two WAS patients with missense mutations (R86H and T45M) that disrupt WIP binding. The calpain inhibitor calpeptin increased WASP levels in activated T and B cells from the WASP patients, but not in primary T cells from the patients or from WIP(-/-) mice. Despite its ability to increase WASP levels proteasome inhibition did not correct the impaired IL-2 gene expression and low F-actin content in T cells from the R86H WAS patient. These results demonstrate that WIP stabilizes WASP and suggest that it may also be important for its function. 相似文献
997.
Prevalence of testicular adrenal rest tumours in male children with congenital adrenal hyperplasia due to 21-hydroxylase deficiency 总被引:1,自引:0,他引:1
Claahsen-van der Grinten HL Sweep FC Blickman JG Hermus AR Otten BJ 《European journal of endocrinology / European Federation of Endocrine Societies》2007,157(3):339-344
OBJECTIVE: Testicular adrenal rest tumours (TART) are a well-known complication in adult male patients with congenital adrenal hyperplasia (CAH), with a reported prevalence of up to 94%. In adulthood, the tumours are associated with gonadal dysfunction most probably due to longstanding obstruction of the seminiferous tubules. The aim of our study was to determine the presence of TART and their influence on gonadal function in childhood. DESIGN: Retrospective study. PATIENTS AND METHODS: Scrotal ultrasound was performed in 34 children with CAH due to 21-hydroxylase deficiency who were between 2 and 18 years old. FSH, LH, testosterone and inhibin B concentrations were measured in serum of 27 patients. RESULTS: TART were detected by ultrasound in 8 out of 34 (24%) children. In two of them, bilateral tumours were found. All lesions were located in the rete testis. Seven patients had the salt-wasting type of CAH; one patient had the simple virilising type of CAH. Mean tumour size was 4.1 mm (range 2-8 mm). In none of the patients were the tumours palpable. Two children with TART were between 5 and 10 years old, the other six children were above 10 years old. In all children with TART, LH, FSH, testosterone and inhibin B levels were similar to the patients without TART. CONCLUSION: TART can be found in CAH children before the age of 10 years. The absence of gonadal dysfunction in our group of children suggests that gonadal dysfunction as frequently reported in adult CAH patients with TART develops after childhood. 相似文献
998.
999.
1000.
Haas JS Earle CC Orav JE Brawarsky P Neville BA Acevedo-Garcia D Williams DR 《Journal of general internal medicine》2007,22(3):396-399
Background Although hospice care can alleviate suffering at the end of life for patients with cancer, it remains underutilized, particularly
by African Americans and Hispanics.
Objective To examine whether the racial composition of the census tract where an individual resides is associated with hospice use.
Design Retrospective analysis of the Surveillance, Epidemiology, and End Results–Medicare file for individuals dying from breast,
colorectal, lung, or prostate cancer (n = 70,669).
Measurements Hospice use during the 12 months before death.
Results Hospice was most commonly used by individuals who lived in areas with fewer African-American and Hispanic residents (47%),
and was least commonly used by individuals who lived in areas with a high percentage of African-American and Hispanic residents
(35%). Hispanics (odds ratio 0.51, 95% confidence interval 0.29–0.91) and African Americans (0.56, 0.44–0.71) were less likely
to use hospice if they lived in a census tract with a high percentage of both African Americans and Hispanics than if they
lived in a low minority tract. African Americans and whites were less likely to receive hospice care if they lived in a census
tract with a high percentage of Hispanics than if they lived in a low minority area.
Conclusions Increasing hospice use may require interventions to improve the delivery of hospice care in minority communities. 相似文献