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81.
Amendments to the child protection legislation in New South Wales (NSW), enacted in October 2014, prioritise adoption over foster care for children who cannot live safely with their families. Therefore, psychologists could have an increasing role in conducting assessments and interventions in this field. The purpose of this article is to provide psychologists and adoption researchers with a conceptual model for the psychosocial adjustment of foster care adoptees with a background of maltreatment. A scoping review of the literature on contributors to outcomes for children adopted from care was conducted. A model of adjustment was proposed in which the relationship between risk factors and adjustment is moderated by both adoptive family factors and relationship factors, and indirectly impacted by system supports. Finally, we name some of the psychological assessments and interventions that may have a key role in enhancing the adoptive family resources and parent–child relationships as moderators of outcomes.  相似文献   
82.
BACKGROUND: Ageing is associated with an altered immune response. Elevated plasma levels of tumour necrosis factor-alpha (TNF-alpha) are present in patients with advanced chronic heart failure (CHF). However, the relationship between age and the immune response in CHF is unknown. METHODS: We investigated the relationship between age and the TNF-alpha generating capacity of lipopolysaccharide (LPS) stimulated peripheral blood mononuclear cells (PBMC) in nine healthy control subjects (mean age 51.6+/-3.6 years, age range 39-75 years) and 22 stable patients with CHF (mean age 68.3+/-1.5 years, age range 52-78 years, NYHA class 3.0+/-0.2). We also tested the TNF-alpha generating capacity of all control subjects and 18 CHF patients in whole blood cultures. RESULTS: Subjects were subgrouped according to baseline TNF-alpha secretion in PBMC cultures into low- and high-responders, with the latter producing TNF-alpha even without LPS stimulation. High-responders produced more TNF-alpha than low-responders at all LPS doses (0.001-10 ng/ml, P<0.0001, repeated measures ANOVA), and high-responders were significantly older than low-responders (controls: 65.8+/-9.2 vs. 47.5+/-2.5 years; patients: 71.9+/-1.9 vs. 65.9+/-1.9 years, both P<0.05). Age correlated with TNF-alpha production in both patients and controls. This effect was independent of NYHA class. CONCLUSIONS: LPS-responsiveness appears to relate to age in both healthy controls and CHF patients. When assessing the immune status of CHF patients, age should therefore be considered an important confounding factor. In whole blood these findings could only be confirmed at the highest LPS concentration used, thus suggesting that certain factors in the blood may be able to abolish LPS activity at lower concentrations.  相似文献   
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84.
Three dimensional flow in the human left atrium   总被引:2,自引:0,他引:2       下载免费PDF全文
BACKGROUND—Abnormal flow patterns in the left atrium in atrial fibrillation or mitral stenosis are associated with an increased risk of thrombosis and systemic embolisation; the characteristics of normal atrial flow that avoid stasis have not been well defined.
OBJECTIVES—To present a three dimensional particle trace visualisation of normal left atrial flow in vivo, constructed from flow velocities in three dimensional space.
METHODS—Particle trace visualisation of time resolved three dimensional magnetic resonance imaging velocity measurements was used to provide a display of intracardiac flow without the limitations of angle sensitivity or restriction to imaging planes. Global flow patterns of the left atrium were studied in 11 healthy volunteers.
RESULTS—In all subjects vortical flow was observed in the atrium during systole and diastolic diastasis (mean (SD) duration of systolic vortex, 280 (77) ms; and of diastolic vortex, 256 (118) ms). The volume incorporated and recirculated within the vortices originated predominantly from the left pulmonary veins. Inflow from the right veins passed along the vortex periphery, constrained between the vortex and the atrial wall.
CONCLUSIONS—Global left atrial flow in the normal human heart comprises consistent patterns specific to the phase of the cardiac cycle. Separate paths of left and right pulmonary venous inflow and vortex formation may have beneficial effects in avoiding left atrial stasis in the normal subject in sinus rhythm.


Keywords: atrium; blood flow; magnetic resonance imaging; haemodynamics  相似文献   
85.
The ability of color Doppler flow mapping to provide intraoperative information about mitral regurgitation (MR) severity and to evaluate adequacy of mitral valve repair was assessed by performing color Doppler echocardiography immediately before and after cardiopulmonary bypass, with the transducer placed directly on the epicardium. In 56 patients, the degree of MR by intraoperative color Doppler correlated well with left ventricular angiography (kappa = 0.80) and with closed-chest preoperative color Doppler (kappa = 0.84) and had good interobserver reproducibility (kappa = 0.88). Good correlation was also seen between closed-chest color Doppler and angiography (kappa = 0.75). After mitral valve repair in 18 patients (15 ischemic MR, 3 cleft valves), color Doppler was used to assess severity of residual MR intraoperatively and postoperatively. Intraoperative color Doppler identified satisfactory repair (MR less than or equal to 2+) in 15 patients and failure (MR greater than or equal to 3+) in 3, whereas conventional surgical assessment of MR by fluid filling of the arrested ventricle failed to provide reliable differentiation. MR severity on subsequent closed-chest color Doppler follow-up did not change significantly compared with intraoperative evaluation after repair. Intraoperative color Doppler provides accurate grading of MR severity, offers instantaneous evaluation of the adequacy of mitral valve repair before chest closure, and appears to predict the degree of postoperative MR seen on subsequent closed-chest follow-up studies.  相似文献   
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87.
The US Food and Drug Administration's (FDA) Total Diet Study (TDS) has been conducted continuously since the early 1960s to measures levels of various pesticide residues, contaminants, and nutrients in foods and to estimate the dietary exposures to these compounds. Both the TDS food list and the consumption amounts used for estimating exposures are based on results of nationwide food consumption surveys, and they are updated periodically to reflect changes in food consumption patterns. The most recent update was completed in 2003 using the same methodology employed in the previous update (1990). The updated food list includes approximately the same number of foods (285) as the previous list (290). Although most (75%) foods are the same in both versions, the new list reflects trends in consumption of foods containing less fat. The updated diets reflect an increase in total food consumption, with most notable increases in consumption of grains and beverages. A case study comparing cadmium exposures calculated from both the 1990 and 2003 versions of the TDS demonstrated the potential impact of changes in both the food list and consumption amounts on TDS exposure estimates.  相似文献   
88.
BACKGROUND: Chronic heart failure (CHF) is a hyperuricemic state, and capillary endothelium is the predominant site of xanthine oxidase in the vasculature. Upregulated xanthine oxidase activity (through production of toxic free radicals) may contribute to impaired regulation of vascular tone in CHF. We aimed to study the relationship between serum uric acid levels and leg vascular resistance in patients with CHF with and without cachexia and in healthy control subjects. METHODS: In 23 cachectic and 44 noncachectic patients with CHF (age, 62 +/- 1 years, mean +/- SEM) and 10 healthy control subjects (age, 68 +/- 1 years), we assessed leg resting and postischemic peak vascular resistance (calculated from mean blood pressure and leg blood flow by venous occlusion plethysmography). RESULTS: Cachectic patients, compared with noncachectic patients and control subjects, had the highest uric acid levels (612 +/- 36 vs 459 +/- 18 and 346 +/- 21 micromol/L, respectively, both P <.0001) and the lowest peak leg blood flow and vascular reactivity (reduction of leg vascular resistance from resting to postischemic conditions: 83% vs 88% and 90%, both P <.005). In all patients, postischemic vascular resistance correlated significantly and independently of age with uric acid (r = 0.61), creatinine (r = 0.47, both P <.0001), peak VO2 (r = 0.34), and New York Heart Association class (r = 0.33, both P <.01). This correlation was not present in healthy control subjects (r = -0.04, P =.9). In multivariate and stepwise regression analyses, serum uric acid emerged as the strongest predictor of peak leg vascular resistance (standardized coefficient = 0.61, P <.0001) independent of age, peak VO2, creatinine, New York Heart Association class, and diuretic dose. CONCLUSIONS: Hyperuricemia and postischemic leg vascular resistance are highest in cachectic patients with CHF, and both are directly related independent of diuretic dose and kidney function. The xanthine oxidase metabolic pathway may contribute to impaired vasodilator capacity in CHF.  相似文献   
89.
The protective effect of nitrogen mustard-induced neutropenia on the development of the GSR was studied. No coagulation defect was found in neutropenic rabbits and simultaneous administration of Thorotrast and endotoxin did not produce intravascular coagulation or renal cortical necrosis. Infusion of neutropenic rabbits with suspensions of viable granulocytes derived from peritoneal exudates reinduced susceptibility to both intravascular coagulation and renal cortical necrosis. It is concluded that the presence of granulocytes is essential for the production of intravascular coagulation by endotoxin.  相似文献   
90.
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