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91.
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Children today experience many transitions within their school careers. One transition in particular, from preschool to kindergarten presents many challenges for children, families, and teachers. A model for planning and carrying out this transition is presented. The model includes developing and implementing the transition process.  相似文献   
93.
Background. Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non-heart-beating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning.

Methods. Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non-heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 μg/kg (n = 7) before initiation of apnea. Non-heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia.

Results. Phenylephrine 25 μg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 ± 0.5 versus 7.7 ± 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 ± 5.3 versus 41.0 ± 3.4 mm Hg; p = 0.04). Phenylephrine 25 μg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09).

Conclusions. Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.  相似文献   

94.
Why should depression screening be conducted in chronically ill populations? Depression is a disabling illness and is very common among patients who have chronic illnesses. Despite its high prevalence in this patient population, depression often goes unrecognized. Having a plan for a population-based screening program for depression can not only identify patients who are at risk of depression, but can also help to foster early treatment and enhanced care for these patients. This article provides an overview of commonly-used depression screening tools and presents an example of how this might be carried out in a healthcare organization.  相似文献   
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The authors describe their preliminary experience with the use of superparamagnetic magnetic resonance (MR) imaging contrast media for suppression of signal from flowing blood. The goal of this work was to determine if a superparamagnetic contrast agent could successfully eliminate blood signal during cardiac-gated MR imaging, thereby eliminating or reducing flow artifacts associated with the complex and variable hemodynamics within the heart chambers. Imaging and data analysis were performed in 17 dogs subjected to experimental myocardial infarction as part of a parallel project. Six doses (0.2, 1, 2, 3.5, 4, 5, and 10 mg/kg) of AMI-25, an experimental contrast agent, were used in the study. Spin-echo imaging was performed immediately before and every 5 minutes (for an average of 25 minutes) after bolus injection of the contrast agent. Variations in the image signal-to-noise ratio relative to a baseline (before injection of contrast agent) image were assessed as a function of dose and time. Preliminary results suggest that a considerable reduction in blood flow artifacts and, hence, increases in image signal-tonoise ratio can be achieved at doses greater than or equal to 3.5 mg/kg, for approximately 20 minutes after injection. Doses equal to or less than 2 mg/kg and images obtained more than 20 minutes after injection (regardless of dose) did not reliably show hemodynamic artifact suppression.  相似文献   
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Background  

This study compared the prognostic value of exercise single-photon emission computed tomographic (SPECT) thallium imaging with that of treadmill exercise score in medically treated patients with coronary artery disease (CAD)  相似文献   
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Colonoscopy has been advocated by some investigators as the most appropriate means of screening asymptomatic patients with a positive family history of colorectal cancer. However, results of such screening have been widely disparate. The purpose of this study was to evaluate the yield of colonoscopy in a cohort of completely asymptomatic individuals with one or two first-degree relatives with a history of colorectal cancer and to compare this yield with that of colonoscopy in a group of patients with apparent anal bleeding. Patients with possible genetic disorders, such as familial polyposis, were excluded. A total of 160 asymptomatic patients and a comparison group of 137 patients with nonacute anorectal bleeding underwent colonoscopy. Colonoscopy was completed in 143 of the 160 study patients (89 percent) and in all of the comparison patients and did not result in any complications. Twenty-two adenomas were found in 17 study patients (10.6 percent); 16 of the 22 adenomas were less than 1 cm in size. In the comparison group, eight adenomas were identified (5.8 percent of patients). No cancers were identified. The difference in polyp frequency between groups was not significant. The relatively low yield of colorectal neoplasms discovered at colonoscopy in this study may in part be due to the small sample size or to the strict criteria used to define these asymptomatic patients but does not lend strong support to the notion that colonoscopy is an appropriate first step in screening the asymptomatic patient with one or two first-degree relatives with colon cancer.  相似文献   
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