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OBJECTIVE: Our purpose was to confirm the local drug delivery of a paclitaxel-eluting balloon by percutaneous intervention of single arterial segments or bifurcations of porcine coronary arteries. METHODS: Eight domestic pigs were subjected to 2 x 30 s Dior balloon dilatation of the mid left anterior descending, left circumflex and proximal right coronary arteries. Bifurcation intervention was performed in six arteries. The dilated, and the distal and proximal reference segments were prepared for tissue paclitaxel concentration measurement. Tissue samples were harvested at mean 1.5, 12, 24 and 48 h after balloon dilatation and plasma samples were taken at various time points. RESULTS: The tissue paclitaxel concentration of the single dilated segment was at 1.5 h postdilatation 1.82+/-1.60 micromol/l, which decreased significantly to 0.73+/-0.27 (P=0.032), 0.62+/-0.34 and 0.44+/-0.31 micromol/l at 12, 24 and 48 h. The bifurcation intervention resulted in 5.10+/-1.80 micromol/l tissue paclitaxel amount in the main branch, which at 12 h had diminished to 1.41+/-1.23 micromol/l (P=0.004). The bifurcation side contained 7.00+/-4.80 micromol/l paclitaxel at 1.5 h postdilatation, which lowered to 2.72+/-0.40 micromol/l (P=0.034). The mean paclitaxel concentration of the reference segments decreased gradually from 0.84+/-0.99 to 0.34+/-0.36 micromol/l (P=0.09), 0.28+/-0.16 and 0.19+/-0.18 micromol/l tissue at 1.5, 12, 24 and 48 h postdilatation, respectively. No paclitaxel was found in the peripheral blood at any time point. CONCLUSION: Short exposure of the coronary artery to paclitaxel with a coated balloon is sufficient for the attainment of an adequate tissue concentration of paclitaxel, which is known to be efficient in inhibiting neointimal growth.  相似文献   
13.
STUDY OBJECTIVES: To determine the effects of different levels of positive end-expiratory pressure (PEEP) during partial liquid ventilation (PLV) on gas exchange, lung compliance, and end-expiratory lung volume (EELV). DESIGN: Prospective animal study. SETTING: Animal physiology research laboratory. SUBJECTS: Nine piglets. INTERVENTIONS: Animals underwent saline solution lavage to produce lung injury. Perflubron was instilled via the endotracheal tube in a volume estimated to represent functional residual capacity. The initial PEEP setting was 4 cm H(2)O, and stepwise changes in PEEP were made. At 30-min intervals, the PEEP was increased to 8, then 12, then decreased back down to 8, then 4 cm H(2)O. MEASUREMENTS AND RESULTS: After 30 min at each level of PEEP, arterial blood gases, aortic and central venous pressures, heart rates, dynamic lung compliance, and changes in EELV were recorded. Paired t tests with Bonferroni correction were used to evaluate the data. There were no differences in heart rate or mean BP at the different PEEP levels. CO(2) elimination and oxygenation improved directly with the PEEP level and mean airway pressure (Paw). Compliance did not change with increasing PEEP, but did increase when PEEP was lowered. EELV changes correlated directly with the level of PEEP. CONCLUSIONS: As previously reported during gas ventilation, oxygenation and CO(2) elimination vary directly with PEEP and proximal Paw during PLV. EELV also varies directly with PEEP. Dynamic lung compliance, however, improved only when PEEP was lowered, suggesting an alteration in the distribution of perflubron due to changes in pressure-volume relationships.  相似文献   
14.
BACKGROUND: Current heart failure (HF) guidelines note that alcohol use should be discouraged or restricted in patients with HF resulting from left ventricular systolic dysfunction. Existing knowledge is limited in the area of HF and alcohol. METHODS AND RESULTS: The purpose of this article is to review the evidence regarding the acute and long-term use of alcohol in the setting of HF. In addition, general aspects about alcohol and alcoholic beverages that are important for understanding and interpreting alcohol-related literature are reviewed and that can be used when discussing alcoholic beverage use with patients with HF. CONCLUSIONS: There is some emerging evidence that suggests light drinking (1 to 14 drinks per week) is safe and even beneficial in HF patients with ischemic left ventricular dysfunction (LVD). However, there are no effects of light drinking in HF patients with nonischemic LVD. Clinicians should reinforce the importance of evidence based pharmacologic and nonpharmacologic therapies in HF.  相似文献   
15.
CONTEXT: Various cosyntropin doses are used to test adrenal function in premature infants, without consensus on appropriate dose or adequate response. OBJECTIVE: The objective of this study was to test the cortisol response of extremely low birth weight infants to different cosyntropin doses and evaluate whether these doses differentiate between groups of infants with clinical conditions previously associated with differential response to cosyntropin. DESIGN: The design was a prospective, nested study conducted within a randomized clinical trial of low-dose hydrocortisone from November 1, 2001, to April 30, 2003. SETTING: The setting was nine newborn intensive care units. PATIENTS: The patients included infants with 500-999 g birth weight. INTERVENTION: The drug used was cosyntropin, at 1.0 or 0.1 microg/kg, given between 18 and 28 d of birth. MAIN OUTCOME MEASURE: We measured the cortisol response to cosyntropin. RESULTS: Two hundred seventy-six infants were tested. Previous hydrocortisone treatment did not suppress basal or stimulated cortisol values. Cosyntropin, at 1.0 vs. 0.1 microg/kg, yielded higher cortisol values (P < 0.001) and fewer negative responses (2 vs. 21%). The higher dose, but not the lower dose, showed different responses for girls vs. boys (P = 0.02), infants receiving enteral nutrition vs. not (P < 0.001), infants exposed to chorioamnionitis vs. not (P = 0.04), and those receiving mechanical ventilation vs. not (P = 0.02), as well as a positive correlation with fetal growth (P = 0.03). A response curve for the 1.0-microg/kg dose for infants receiving enteral nutrition (proxy for clinically well infants) showed a 10th percentile of 16.96 microg/dl. Infants with responses less than the 10th percentile had more bronchopulmonary dysplasia and longer length of stay. CONCLUSIONS: A cosyntropin dose of 0.1 microg/kg did not differentiate between groups of infants with clinical conditions that affect response. We recommend 1.0 microg/kg cosyntropin to test adrenal function in these infants.  相似文献   
16.
Earlier studies have shown evidence for various sources of observed spousal similarity regarding different traits and characteristics. We explored the relative contribution of non-random mating and convergence to spouse similarity with respect to global mental health, life satisfaction, optimism, and type A personality. We used population-based data collected for the Nord-Trøndelag Health Study (1984–1986) and prospective registry information about when and with whom people entered into marriage/cohabitation between 1970 and 2000 for 19,599 married/cohabitating couples and 1,551 future couples that entered into marriage/cohabitation during the 16 years after data collection. Couples were categorized by interval between data collection and entry into marriage/cohabitation. Age-adjusted polychoric correlations calculated for each group were used as the dependent variables in non-linear, segmented regression analysis, with time since or until marriage/cohabitation as the independent variable. Initial correlations between partners-to-be were low to moderate, typically around one-half of the values estimated in existing couples, indicating both non-random mating and early convergence. There appeared to be moderate divergence during the first 20 years of marriage/cohabitation and moderate convergence during the rest of life.  相似文献   
17.
BackgroundNursing documentation is essential for facilitating the flow of information to guarantee continuity, quality and safety in care. High-quality nursing documentation is frequently lacking; the implementation of computerized decision support systems is expected to improve clinical practice and nursing documentation.AimThe present study aimed at investigate the effects of a computerized decision support system and an educational program as intervention strategies for improved nursing documentation practice on pressure ulcers and malnutrition in nursing homes.Design, setting and participantsAn intervention study with two intervention groups and one control group was used. Fifteen nursing homes in southern Norway were included. A convenience sample of electronic healthcare records from 46 units was included. Inclusion criteria were records with presence of pressure ulcers and/or malnutrition. The residents were assessed before and after an intervention of a computerized decision support system in the electronic healthcare records. Data were collected through a review of 150 records before (2007) and 141 records after the intervention (2009).MethodsThe nurses in intervention group 1 were offered educational sessions and were trained to use the computerized decision support system, which they used for eight months in 2008 and 2009. The nurses in intervention group 2 were offered the same educational program but did not use the computerized decision support system. The nurses in the control group were not subject to any intervention. The resident records were examined for the completeness and comprehensiveness of the documentation of pressure ulcers and malnutrition with three data collection forms and the data were analyzed with non-parametric statistics.ResultsThe implementation of the computerized decision support system and the educational program resulted in a more complete and comprehensive documentation of pressure ulcer- and malnutrition-related nursing assessments and nursing interventions.ConclusionThis study provides evidence that the computerized decision support system and an educational program as implementation strategies had a positive influence on nursing documentation practice.  相似文献   
18.
The aim of this study was to investigate whether agility activity with dogs can be used to motivate less active children in physical activity and how such activity is experienced by parents and handlers. Data were collected through qualitative interviews with handlers and parents of the participating children. Agility with dogs appeared to motivate less active children to participate in, and endure, demanding physical activity. Joy and bonding with the dog appeared to be key elements in the motivational process. Motivation, initiation, and sustainment of activity over time are beneficial for children.  相似文献   
19.
International Journal of Clinical Pharmacy - Background Medication-related hospital admissions (MRAs) are frequently used to measure outcomes in studies involving medication reviews. The process of...  相似文献   
20.
The complexity of the nonvisual photoreception systems in teleosts has just started to be appreciated, with colocalization of multiple photoreceptor types with unresolved functions. Here we describe an intricate expression pattern of melanopsins in early life stages of the marine flat fish Atlantic halibut (Hippoglossus hippoglossus), a period when the unpigmented brain is directly exposed to environmental photons. We show a refined and extensive expression of melanopsins in the halibut brain already at the time of hatching, long before the eyes are functional. We detect melanopsin in the habenula, suprachiasmatic nucleus, dorsal thalamus, and lateral tubular nucleus of first feeding larvae, suggesting conserved functions of the melanopsins in marine teleosts. The complex expression of melanopsins already at larval stages indicates the importance of nonvisual photoreception early in development. Most strikingly, we detect expression of both exorhodopsin and melanopsin in the pineal complex of halibut larvae. Double‐fluorescence labeling showed that two clusters of melanopsin‐positive cells are located lateral to the central rosette of exorhodopsin‐positive cells. The localization of different photopigments in the pineal complex suggests that two parallel photoreceptor systems may be active. Furthermore, the dispersed melanopsin‐positive cells in the spinal cord of halibut larvae at the time of hatching may be primary sensory cells or interneurons representing the first example of dispersed high‐order photoreceptor cells. The appearance of nonvisual opsins early in the development of halibut provides an alternative model for studying the evolution and functional significance of nonvisual opsins. J. Comp. Neurol. 522:4003–4022, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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