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41.
Michael W Ross Amy Jo Harzke Deborah P Scott Kelly McCann Michael Kelley 《AIDS education and prevention》2006,18(6):504-517
We report select outcomes from an evaluation of Project Wall Talk, a community-based, peer-led HIV prevention education program implemented in 36 Texas State prison units. Peer educators completed questionnaires prior to receipt of a 40-hour intensive training (N = 590) and at 9-month follow-up (N = 257). Students (N = 2506) completed questionnaires pre- and post-receipt of peer educator-led HIV education sessions. Peer educators and their students showed significant increases in HIV-related knowledge. Peer educators showed significant increases in assessment of their skills as educators. For both peer educators and students, significant differences in HIV-related knowledge were indicated across categories of prior educational level attained and race/ethnicity; no such differences were indicated at follow-up. Compared with baseline, a significantly greater proportion of peer educators reported ever having had an HIV test. After receiving peer-led education, a significantly smaller proportion of students reported they knew their HIV status and more indicated plans to take an HIV test. Additionally, in months 12 and 18 following program implementation, the numbers of HIV tests at the five units that implemented the peer education program were roughly twice that of five, matched comparison units without the peer education program. Based on peer educator reports, we projected that peer educators (N = 257) may have as many as 84,000 or more annual opportunities to share HIV-related knowledge with other prisoners outside the classroom. 相似文献
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Children with no known prior vitamin A deficiency exhibited a significant decline in their serum retinol levels during the acute phase of measles. This decline in circulating retinol was associated with increased duration of fever, higher hospitalization rates, and decreased antibody titers. 相似文献
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The present study in the anesthetized dogs was designed to test the hypothesis that atrial natriuretic factor (ANF) attenuates whole kidney tubuloglomerular feedback (TGF) mediated decreases in renal blood flow (RBF) and glomerular filtration rate (GFR) produced by hypertonic saline (HS). Secondly, as adenosine (AD) has been implicated as a metabolic mediator of TGF, we also hypothesized that ANF would antagonize the renal actions of AD. To test this hypothesis, RBF and GFR were assessed in response to hypertonic saline (HS, 16%, i.r.) or adenosine (AD, 0.1 mumol/min, i.r.) in the presence and absence of exogenous ANF (100 ng/kg/min, i.r.). ANF attenuated HS-mediated reductions in GFR (HS, -39.6 +/- 9.8 ml/min vs. HS + ANF, -14.3 +/- 4.5 ml/min, P less than 0.05) and in RBF (HS, -143 +/- 35 ml/min vs. HS + ANF, -5 +/- 22 ml/min, P less than 0.05). GFR was reduced by AD (-9.2 +/- 3.0 ml/min, P less than 0.05), but maintained by AD + ANF (-0.4 +/- 2.0 ml/min, NS). A transient adenosine-mediated vasoconstriction was attenuated by ANF (AD, -54.5 +/- 3.6 ml/min vs. AD + ANF, -3.7 +/- 3.1 ml/min, P less than 0.005). We conclude that ANF at pharmacologic concentrations attenuates at the whole kidney level hypertonic saline and adenosine-mediated reductions in RBF and GFR. 相似文献
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45.
Amy S. Pikalow Mary E. Flynn Robert L. Searls 《Anatomical record (Hoboken, N.J. : 2007)》1994,238(3):407-414
Experiments were done to investigate the cause of the cranial (mesencephalic) flexure of the chick brain during stages 10 to 14. Measurements of the length and thickness of the roof and floor of the mesencephalon gave values similar to the values obtained previously by others. The labeling index was determined in the roof and floor of the prosencephalon, mesencephalon, and rhombencephalon as a preliminary measure of cell division. The labeling index was about the same in all regions, and was high enough to suggest that most of the cells were dividing. The labeling indices did not suggest that differential growth was caused by differential rates of cell division in the roof and floor of the mesencephalon. It was found through time lapse photography that the foregut and heart remained stationary along the rostrocaudal axis, whereas the prosencephalon moved rostrally and the mesencephalon underwent flexure. Measurements suggested that the neural tube cranial to the otic primordium grew in volume exponentially at a rate consistent with the labeling index. The rostral tip of the neural tube was observed to be linked to the rostral tip of the foregut by the ectoderm that formed Rathke's pouch at the neural tube and the pharyngeal membrane (prospective stomodeum) at the foregut. As the neural tube grew in length, the link between the neural tube and the foregut did not. We suggest that because of this link, the growing neural tube had to bend around the foregut, forming the cranial flexure, and the ectoderm folded where it attached to the prosencephalon, forming Rathke's pouch. © 1994 Wiley-Liss, Inc. 相似文献
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48.
The renal action of atrial natriuretic peptide during control of glomerular filtration 总被引:1,自引:0,他引:1
Studies were performed in anesthetized dogs (N = 7) to determine the effects of synthetic atrial natriuretic peptide (ANP) on sodium excretion in the presence and absence of control of glomerular filtration rate produced by suprarenal aortic clamping. Intrarenal infusion of synthetic atrial natriuretic peptide (0.3 micrograms/kg/min) significantly increased glomerular filtration rate from 29.3 +/- 3.0 to 43.2 +/- 4.4 ml/min, urinary sodium excretion from 20.1 +/- 10.3 to 223.3 +/- 52.3 microEq/min, fractional sodium excretion from 0.47 +/- 0.19 to 3.75 +/- 0.59%. In contrast, aortic clamping blocked the increase in glomerular filtration rate in association with an attenuated natriuresis. Urinary sodium excretion increased from 6.3 +/- 2.3 to 68.3 +/- 23.4 microEq/min and fractional sodium excretion increased from 0.15 +/- 0.04 to 0.90 +/- 0.30%. Despite this differential response in glomerular filtration rate and sodium excretion, whole kidney fractional delivery of sodium from the proximal tubule as estimated by the fractional excretion of lithium increased during both unclamped (17.7 +/- 1.8 to 30.4 +/- 0.8%) and clamped (12.9 +/- 2.1 to 23.9 +/- 2.7%) periods. These studies demonstrate that atrial natriuretic peptide-induced natriuresis is importantly mediated by an increase in glomerular filtration rate and decrease in tubular reabsorption. 相似文献
49.
Although psychological debriefing (PD) represents the most common form of early intervention for recently traumatized people, there is little evidence supporting its continued use with individuals who experience severe trauma. This review identifies the core issues in early intervention that need to be addressed in resolving the debate over PD. It critiques the available evidence for PD and the early provision of cognitive-behavioral therapy (CBT). Based on available evidence, we propose that psychological first aid is an appropriate initial intervention, but that it does not serve a therapeutic or preventive function. When feasible, initial screening is required so that preventive interventions can be used for those individuals who may have difficulty recovering on their own. Evidence-based CBT approaches are indicated for people who are at risk of developing posttraumatic psychopathology. Guidelines for managing acutely traumatized people are suggested and standards are proposed to direct future research that may advance our understanding of the role of early intervention in facilitating adaptation to trauma. 相似文献
50.