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51.
52.
OBJECTIVE: To test the hypothesis that perfluorocarbon (PFC) priming before surfactant administration improves gas exchange and lung compliance, and also decreases lung injury, more than surfactant alone. DESIGN: Prospective, randomized animal study. SETTING: Animal research laboratory of Children's Hospital of St. Paul. SUBJECTS: Thirty-two newborn piglets, weighing 1.55 +/- 0.18 kg. INTERVENTIONS: We studied four groups of eight animals randomized after anesthesia, paralysis, tracheostomy, and establishment of lung injury using saline washout to receive one of the following treatments: a) surfactant alone (n = 8); b) priming with the PFC perflubron alone (n = 8); c) priming with perflubron followed by surfactant (n = 8); and d) no treatment (control; n = 8). Perflubron priming was achieved by instilling perflubron via the endotracheal tube in an amount estimated to represent the functional residual capacity, ventilating the animal for 30 mins, and then removing perflubron by suctioning. After all treatments were given, animals were mechanically ventilated for 4 hrs. MEASUREMENTS AND MAIN RESULTS: We evaluated oxygenation, airway pressures, respiratory system compliance, and hemodynamics at baseline, after induction of lung injury, and at 30-min intervals for 4 hrs. Histopathologic evaluation was carried out using a semiquantitative scoring system and by computer-assisted morphometric analysis. After all treatments, animals had decreased oxygenation indices (p < .001) and increased respiratory system compliance (p < .05). Animals in PFC groups had similar physiologic responses to treatments as animals treated with surfactant only; both the PFC-treated groups and the surfactant-treated animals required lower mean airway pressures throughout the experiment (p < .001) and had higher pH levels at 90 and 120 mins (p < .05) compared with the control group. Pathologic analysis demonstrated decreased lung injury in surfactant-treated animals compared with animals treated with PFC or the controls (p < .02). CONCLUSIONS: Priming the lung with PFC neither improved the physiologic effects of exogenous surfactant nor improved lung pathology in this animal model.  相似文献   
53.

Purpose of Review

Myocardial infarction (MI) leading to heart failure displays an important cause of death worldwide. Adequate restoration of blood flow to prevent this transition is a crucial factor to improve long-term morbidity and mortality. Novel regenerative therapies have been thoroughly investigated within the past decades.

Recent Findings

Increased angiogenesis in infarcted myocardium has shown beneficial effects on the prognosis of MI; therefore, the proangiogenic capacity of currently tested treatments is of specific interest. Molecular imaging to visualize formation of new blood vessels in vivo displays a promising option to monitor proangiogenic effects of regenerative substances.

Summary

Based on encouraging results in preclinical models, molecular angiogenesis imaging has recently been applied in a small set of patients. This article reviews recent literature on noninvasive in vivo molecular imaging of angiogenesis after MI as an integral part of cardiac regeneration.
  相似文献   
54.
OBJECTIVE: To examine the relationship between plasma cytokine levels and cardiac and hemodynamic function. DESIGN: Measurement of cytokines and the systolic (left ventricular dimensions, heart rate, and cardiac output) and diastolic (early and late transmitral peak flow velocity: E and A-waves and their ratio) functions of the left ventricle (assessed by echocardiography) in rabbits. SETTING AND INTERVENTIONS: Laboratory and echocardiographic analyses were performed at baseline and at 1, 3, 6, 12, and 24 h after acute necrotizing pancreatitis induction (Group ANP), in rabbits after somatostatin pretreatment (Group S-ANP) and in sham-operated controls (Group C). MEASUREMENTS AND RESULTS: Left ventricular dilatation occurred at 6 h and cardiac output was increased 3 h after induction of acute necrotizing pancreatitis. Somatostatin pretreatment mitigated the left ventricular enlargement and filling abnormalities. Plasma level of IL-6 was increased significantly 3 h after pancreatitis induction, but to a lesser extent in Group S-ANP, while somatostatin prevented TNFalpha release (IL-6: Group ANP: 0, 0, 518+/-139, 956+/-125, 373+/-48, and 122+/-37 pg/ml; Group S-ANP: 0, 0, 191+/-68, 261+/-49, 23+/-13, and 0 pg/ml; TNFalpha: Group ANP: 88+/-42, 371+/-40, 2963+/-291, 276+/-30, 197+/-106, and 23+/-14 U/l; Group S-ANP: 91+/-34, 41+/-25, 68+/-42, 25+/-9, 0, and 0 U/ml). The increase in plasma level of IL-6 correlated significantly with left ventricular end-diastolic diameter and volume, cardiac output, and diastolic dysfunction. CONCLUSIONS: Plasma levels of IL-6, but not TNFalpha correlate with cardiac output and left ventricular filling characteristics in acute pancreatitis. Somatostatin pretreatment improves the cardiac and hemodynamic changes, probably through the decrease in cytokine release.  相似文献   
55.
OBJECTIVES: To assess whether easy access to medical information of the emergency department's (ED) frequent users would be useful to patient care in the ED and at primary healthcare centres (PHCs), and if resource utilization in the following year would be affected. METHODS: During a 6-month period, frequent users presenting to the ED of Karolinska University Hospital Huddinge, Sweden, were randomized by the electronic database system into an intervention (n=834) or control group (n=965), the definition being three or more visits in 12 months before the index visit. Printout case notes, from the intervention patients' last three visits, were made accessible to the ED physicians and optionally forwarded to the patient's PHC physician. Usefulness of this enhanced information was measured by questionnaires, whereas healthcare utilization was compiled from the electronic database. RESULTS: The case notes of 59 (7.1%) intervention patients were forwarded to the respective PHCs. Of these, access to the enhanced patient information was deemed useful in 82% cases in the ED, versus 76% in PHCs. The mean number of ED visits in the following year did not differ significantly in the total intervention group as compared with the controls: 4.0 and 3.9, respectively (P=0.49). Nor were there any differences in utilization of other care resources. CONCLUSION: Although only a small subgroup's information was shared, yielding no decrease in overall healthcare utilization, the study indicated benefits of the enhanced information at the respective care level and also had important clinical and organizational implications.  相似文献   
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Discrete choice experiments (DCEs) become increasingly popular to value outcomes for health economic studies and gradually gain acceptance as an input into policy decisions. Developing attributes is a key aspect for the design of DCEs, as their results may misguide decision-makers if they are based on an inappropriate set of attributes. However, the area lacks guidance, and current health-related DCE studies vary considerably in their methods of attribute development, with the consequent danger of providing an unreliable input for policy decisions. The aim of this article is to inform the progress toward a more systematic approach to attribute development for DCE studies in health. A systematic review of the published health-related DCE literature was conducted to lay the foundations for a generic framework which was tested in a case study of alcohol misuse interventions. Four stages of a general attribute development process emerged: (i) raw data collection; (ii) data reduction; (iii) removing inappropriate attributes; and (iv) wording. The case study compared and contrasted a qualitative and mixed-methods approach for the development of attributes for DCEs in the area of alcohol misuse interventions. This article provides a reference point for the design of future DCE experiments in health.  相似文献   
58.
Aleutian mink disease virus (AMDV) is a severe progressive disease causing multiple different clinical syndromes in mink. In Denmark, the disease is notifiable and under official control. The control programme, based on serological screening, has confined successfully AMDV to the northern part of Denmark. However, re-infections and new introductions of virus into farms require a confirmatory virological test to verify the positive test results of single animals and ultimately to investigate disease transmission. A one step PCR amplifying a 374-base fragment of the NS1 gene of AMDV was compared to the counter-current immune electrophoresis (CIE) routinely used in the serological screening programme. Mink organs (n = 299) obtained from 55 recently infected farms and 8 non-infected farms from 2008 to 2010 were tested by PCR, and the results were found to have a high correlation with the serological status of the mink. The relative diagnostic sensitivity of the PCR was 94.7%, and the relative diagnostic specificity was 97.9% when read in parallel with the CIE. PCR positive samples were sequenced and phylogenetic analysis revealed high similarity within the analysed AMDV strains and to AMDV strains described previously.  相似文献   
59.
60.
Hwang C‐C, Pintye M, Chang L‐C, Chen H‐Y, Yeh K‐Y, Chein H‐P, Lee N & Chen J‐R
(2011) Histopathology 59 , 984–992 Dual‐colour chromogenic in‐situ hybridization is a potential alternative to fluorescence in‐situ hybridization in HER2 testing Aim: Dual‐colour chromogenic in‐situ hybridization (dc‐CISH) is an emerging methodology for characterizing genomic alterations. This study was aimed at evaluating the performance of a dc‐CISH kit (ZytoVision) in determining human epidermal growth factor receptor 2 (HER2) status in breast cancer. Methods and results: Two hundred and twenty‐eight invasive breast carcinomas arranged in tissue microarrays were analysed in parallel with dc‐CISH, fluorescence in‐situ hybridization (FISH), and immunohistochemistry. Of 227 tumours with available FISH and dc‐CISH results, HER2 amplification and non‐amplification were detected in 49 (21.6%) and 178 (78.4%) tumours, respectively, by both assays. The concordance between dc‐CISH and FISH results showed 100% agreement (κ‐coefficient = 1.00). Immunohistochemically, 162 (71%), 25 (11.0%) and 41 (18%) tumours were scored 0/1+, 2+, and 3+, respectively. The corresponding results with both FISH and dc‐CISH demonstrated HER2 amplification in two (3.2%), nine (36%) and 38 (93%) tumours, respectively. Complete consensus among these three methods was observed in 197 cases, representing 98% of all 3+ and 0/1+ tumours (κ‐coefficient = 0.92). Confirmatory testing of 25 2+ tumours showed complete consensus between FISH and dc‐CISH. Conclusions: dc‐CISH is a promising alternative to FISH in HER2 testing, and the single‐institute incidence of HER2 amplification in breast cancer in Taiwan is 21.2%.  相似文献   
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