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31.
This study focuses on 422 African American families with two caregivers as children transition into adolescence. The family stress model was tested longitudinally using structural equation modeling. Results showed that economic stress was associated with economic pressure and depressive symptoms among caregivers, which in turn was related to caregiver conflict. Higher levels of conflict had a negative influence on parenting quality at Wave 2, and this was linked to adolescent functioning. The depressive symptomology of secondary caregivers (SCs) exerted a greater indirect effect in the models than that of primary caregivers (PCs) and had a direct relationship to adolescent's positive adjustment. Moderational effects of caregiver conflict on the link between economic pressure/adolescent outcomes and economic pressure/hostile parenting were also tested. The case for the importance of including PCs and SCs of children and adolescents in future research focusing on African American families facing economic hardship is made.  相似文献   
32.
Average bark-to-bark resistance of the IML Resistograph PD400 (hereafter referred to as ‘Resi’) was found to provide strong linear correlations with the basic density of 12-mm-diameter increment cores taken from standing plantation eucalypt trees. Relationships between Resi values and approximately 2 000 cores (predominantly Eucalyptus globulus but some E. nitens) were examined across seven studies (representing samples from nine distinct sites) in Tasmania, Victoria and Western Australia. Custom-written software was developed to process the Resi traces to automatically perform a linear baseline correction of the trace, and extract:
  • over-bark and under-bark diameter

  • bark thickness

  • average resistance of the bark-to-bark (under-bark) trace

  • average resistance of the outer 50 mm on the entry and exit side of the traces.

Baseline correction was needed to counter the variable effects among trees of needle drag across the diameter, largely a function of tree diameter and wood density.

Individual traces were collected in less than 20 s tree?1. The sampling conditions of 150 cm min?1 speed of forward movement (feed speed) and 3 500 revolutions per minute (rpm) were identified as optimal for the plantation eucalypts studied. The relationship between different feed speeds and rpm were linear and coefficients determined to allow average Resi resistance to be converted to a common set of sampling conditions. A simple linear regression was identified in each study to define a slope and intercept to convert the Resi values to basic density and determine the variance between them. Resi traces from different studies were not always collected using the same instrument and this is believed to explain most of the between-study variance in slope and intercept.

Trace processing software was built into a web-based package that is available to make trace processing easy, with defined variables downloadable for use in routine plantation assessment. Users can change the default slope and intercept values to suit their individual instruments or species as required. Further work is required to fully define the effects of instrument, site and species on these relationships.

The IML Resistograph PD400 was found to be an accurate and quick (40–70 trees hour?1 person?1) infield tool for estimating diameter and wood density in standing trees. When combined with automated, web-based processing software the methodology is among the lowest cost options conceivable for wood density assessment of plantation eucalypts.  相似文献   
33.

Context

To meet the growing need for palliative care in low-resource countries, palliative care programs should be evidence based and contextually appropriate. This study was conducted to synthesize the current evidence to guide future programmatic and research efforts.

Objectives

This systematic review evaluated palliative care outcome measures, outcomes, and interventions in low-resource countries.

Methods

After title searches, abstracts and full-text articles were screened for inclusion. Data were extracted to report on intervention models, outcome measures used, and intervention outcomes.

Results

Eighteen papers were reviewed, reporting on interventions conducted across nine low-resource countries. These interventions evaluated home-based palliative care models; a community-managed model; palliative care integrated with hospitals, hospices, or HIV clinics; and models focused on patients' self-management. Three studies were randomized controlled trials. Other studies used nonrandomized trials, cohort studies, mixed methods, pre-post test evaluation, cost-accounting evaluation, and cross-sectional surveys. Thirteen studies measured physical outcomes, 10 using multidimensional instruments. Nine studies measured psychological outcomes, eight using multidimensional instruments. Nine studies measured social outcomes, seven using multidimensional instruments. Nine studies measured outcomes across multiple domains. Across outcomes evaluated, results were reported in the direction of benefit associated with palliative care interventions.

Conclusion

Many palliative care intervention models exist to serve patients in low-resource countries. Yet, limited high-quality evidence from low-resource countries is available to document intervention outcomes. Rigorous experimental studies and greater measurement of multidimensional aspects of palliative care are needed to advance the science of palliative care in low-resource settings.  相似文献   
34.
35.
Graham J  Potts HW  Ramirez AJ 《Lancet》2002,360(9349):1975-6; author reply 1976
  相似文献   
36.
Radioimmunoassays that detect specifically peptide sequences within either the biologically active amino region (N-assay) or inactive carboxyl region (C-assay) of parathyroid hormone (PTH) were used to evaluate the metabolism of PTH during and after infusion and injection of homogeneous (containing less than 0.1% hormonal fragments) intact bovine PTH (bPTH) into calves. During continuous infusions of hormone, when constant blood levels of immunoreactive PTH were reached, a dissociation between the concentrations of amino versus carboxyl immunoreactivity was observed; concentrations of hormone measured by the C-assay rose to a level of approximately three times higher than that measured by the N-assay. Analysis by gel filtration of immunoreactive PTH in plasma samples from calves after injection of hormone showed the rapid disappearance of intact hormone (N- and C-assays) and the appearance of a large fragment detected by the C-assay but not by the N-assay. The hormonal fragment lacked antigenic determinants within the amino peptide sequence required for biologic activity. No additional fragments of PTH were detected by gel filtration using the N- and C-assays. No detectable conversion of intact PTH to hormonal fragments occurred during incubation in vitro in bovine serum. The results are consistent with the concept that PTH is metabolized after entry into the circulation at peripheral sites located outside the vascular space, resulting in the rapid disappearance from blood of intact hormone and the appearance of a biologically inactive hormonal fragment(s). These studies done in calves agree with earlier studies done in dogs and man and point to the existence in mammals of common pathways for the peripheral metabolism of PTH.  相似文献   
37.
Specific subsets of the adult population are at an increased risk of problem gambling behaviors. Previous research among these subsets has found increased rates of disordered gambling among those with drug use, alcohol use, mood, anxiety, and personality disorders. To what extent this may apply to the HIV population, known to have a high burden of co-occurring substance use and mental disorders, is not known The current study also examined the effectiveness of The Brief Biosocial Gambling Screen (BBGS) for the diagnosis of gambling disorder.

This study examined the prevalence of gambling behaviors and disordered gambling in patients enrolled in an urban HIV clinic. 100 people living with HIV (PLWH) were assessed on gambling behaviors, impulsivity, and criterion on disordered gambling. Screening for gambling disorder using the BBGS was compared to the American Psychiatric Association DSM-5 criterion.

The mean age was 53, 44% were female, 60% completed high school or above, and 80% self-identified as unemployed/disabled. 13% met four or more criteria for gambling disorder according to DSM-5 criteria. Participants that met criteria were more likely to report marijuana (p?=?.044) and heroin (p?=?.002) use, and greater impulsivity (p?<?0.00001) when compared to participants who did not meet criteria. The BBGS was able to effectively screen individuals for disordered gambling with a sensitivity of 100%, specificity of 90.8%, positive predictive value of 56.2%, and a negative predictive value of 100%.

These results suggest that urban HIV clinics may need to consider actively screening for gambling disorders, and referring to appropriate counseling and treatment for those who screen positive.  相似文献   

38.
Of 197 consecutive patients having aortocoronary bypass grafts over a 30 month period, 38 (19 per cent) had ECG evidence of myocardial infarction. The infarctions occurred more commonly in patients receiving multiple grafts. The infarctions were usually in areas supplied by grafted vessels. The infarctions occurred most often in the inferior wall, even when multiple vessels were grafted. Eleven patients with intraoperative infarction have had repeat postoperative coronary arteriograms. Seven had all grafts patent; three of these patients had hypokinesis of the infarcted wall. Four of the 11 patients had one or more occluded grafts; three of these patients had an area of hypokinesis. We conclude that intraoperative myocardial infarction is a common problem in aortocoronary bypass surgery and is not necessarily caused by graft occlusion.  相似文献   
39.
A male infant presented at birth with severe coarctation of the aorta and marginal left ventricular and mitral valve dimensions associated with a large secundum atrial septal defect. Following successful arch repair, the left ventricle remained small with preferential left‐to‐right atrial shunting and a dilated right ventricle. Clinically, the infant continued with tachypnea, poor feeding, and failure to thrive. At 4 months of age, the defect was closed with an Amplatzer Atrial Septal Occluder which resulted in immediate left ventricular cavity enlargement and clinical improvement.  相似文献   
40.
Parathyroid hormone (PTH) is rapidly metabolized, mainly by liver and kidney, to smaller fragments that are believed to be biologically inactive. The significance of this peripheral metabolism in the overall actions of PTH is unclear. Generation of circulating biologically active amino-terminal PTH fragments during metabolism in vivo has been suggested by certain observations in vitro, and what are believed to be amino-terminal fragments may be detectable in blood under pathological circumstances in vivo (such as renal failure and coexistent hyperparathyroidism) when highly sensitive assays are employed. We recently reported, however, that administration to normal rats of [35S]bovine PTH ([35S]bPTH) directly labelled at amino-terminal methionines, followed by high-resolution chromatographic analysis of extracted [35S]peptides, does not result in appearance of radioactive amino-terminal fragments in blood, even when the tracer is continuously infused to near-physiological plasma concentrations. We have now employed these techniques to address a second question regarding hormonal metabolism: is hormonal metabolism modified during metabolic perturbations such as changing calcium availability or altered levels of calciotrophic hormones? Metabolism of [35S-Met]bPTH (900 Ci/mmol), either alone or together with [3H-Pro]bPTH, however, did not lead to alterations in the rate of hormonal clearance nor to detectable circulating amino-terminal fragments, either in calcium-deprived or thyroparathyroidectomized rats or when animals were first rendered intoxicated with vitamin D or maintained on a high calcium intake. Likewise, tissue localization and specific cleavage patterns of intact hormone in liver or kidney were all unaltered by these various manoeuvres.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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