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81.
82.
D Blanco Vargas V Moral García J Recio Corral J Torras J M Ferrer 《Revista espa?ola de anestesiología y reanimación》1989,36(1):12-15
Venous pressure between the external jugular vein (EJV), and the superior caval vein (SCV) was compared in 15 patients, free of cardiorespiratory disease and undergoing abdominal surgery. In each patient data was taken in four different positions: A) anaesthetized patient in supine position and mechanical ventilation; B) anaesthetized patient in Trendelenburg position and mechanical ventilation; C) anaesthetized patient in anti-Trendelenburg and mechanical ventilation, and D) awake patient in supine position and spontaneous ventilation. A short, thick catheter with unique end lumen was used for EJV, and a long catheter from the basilic vein, to the SCV. Significant differences between mean and standard deviations of EJV and SCV were not founded. Linea correlation for the 4 positions was performed (r = 0.97, 0.91, 0.88 and 0.60 respectively) being significant for A-B y C positions. 4.5 cm H2O was the maximal difference obtained between SCV and EJV for A, B and C positions, and 10 cm H2O the maximal difference for the D position. The mean changes between the positions A-B, A-C and A-D was compared and significant differences (p less than or equal to 0.001) for A-C were seen, whereas A-B did not attain significant differences. We conclude that the EJV cannulation, with a short and thick catheter, allow the central venous pressure control during anaesthesia, in supine position, Trendelenburg and anti-Trendelenburg, but not during the recovery. 相似文献
83.
Anguita M Montes P Jordán A Casares G Gómez I Recio J Martínez A Zumalde J Povar J Ridocci F Roig E Batlle E 《Revista espa?ola de cardiología》2006,59(5):465-472
INTRODUCTION AND OBJECTIVES: Recent studies have shown that brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are useful in the diagnosis of heart failure in patients presenting with dyspnea. However, the cutoff values used with these markers vary according to patient characteristics and dyspnea severity. The aim of this study was to investigate the diagnostic accuracy of using the plasma NT-proBNP level for identifying heart failure in a heterogeneous population of patients with dyspnea. METHODS: A multicentre study involving 247 consecutive patients with recent-onset dyspnea was carried out at 12 Spanish hospitals. Patients previously diagnosed with heart failure or any other condition known to cause dyspnea were excluded. RESULTS: Of the 247 patients, 161 (65%) had heart failure. The remaining 86 (35%) presented with dyspnea of non-cardiac origin. Plasma NT-proBNP levels were higher in patients with heart failure (5600 [7988] pg/mL vs 1182 [4406] pg/mL; P=.0001), and increased as functional status deteriorated (P=.036). The area under the receiver operating characteristic curve was 0.87 (0.02) (95% CI, 0.81-0.91) for the optimum cutoff value of 1335 pg/mL. The sensitivity of this cutoff value for diagnosing heart failure was 77% (95% CI, 70%-83%), the specificity was 92% (95% CI, 84%-97%), the positive predictive value was 94%, and the negative predictive value was 68%. CONCLUSIONS: The plasma NT-proBNP concentration provides an accurate means of diagnosing heart failure. However, the negative predictive value found in this study was somewhat lower than the values found in previous studies involving more homogeneous patient populations. 相似文献
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85.
A. Anadón M.A. Martínez I. Ares E. Ramos M.R. Martínez-Larrañaga M.M. Contreras M. Ramos I. Recio 《Food and chemical toxicology》2010
The Lowpept® is a powdered casein hydrolysate containing the antihypertensive peptides RYLGY and AYFYPEL, two sequences that correspond to αs1-casein f (90–94) (RYLGY) 1 and αs1-casein f (143–149) (AYFYPEL) 1. To support the safety, Lowpept® has been examined in an acute and in a 4-week repeated dose oral toxicity studies in rats. Powdered casein hydrolysate administered in a single oral gavage dose of 2000 mg/kg resulted in no adverse events or mortality. Also, casein hydrolysate administered as a daily dose of 1000 mg/kg for 4 weeks by gavage resulted in no adverse events or mortality. No evidence or treatment-related toxicity was detected during both studies. Data analysis of body weight gain, food consumption, clinical observations, blood biochemical, haematology, organ weight ratios and histopathological findings did not show significant differences between control and treated groups. It is concluded that the casein hydrolysate containing the peptides RYLGY and AYFYPEL orally administered to rats was safe and that not treatment-related toxicity was detected even at the highest doses investigated in both acute (2000 mg/kg of body weight) and repeated dose (4 weeks) oral (1000 mg/kg of body weight) toxicity studies. 相似文献
86.
MV Pravin Charles Joshy M Easow Noyal M Joseph M Ravishankar Shailesh Kumar Umadevi Sivaraman 《The Australasian medical journal》2013,6(9):430-434
Background
Ventilator-associated pneumonia (VAP) is a common type of nosocomial pneumonia encountered in intensive care units. There are several aetiological agents which make treatment challenging. Improper antibiotic treatment of ventilated patients may lead to the emergence of multidrug resistant (MDR) pathogens.Method
A prospective study was performed over a period of 20 months. Our study had two arms: the first, ‘Incidence and risk factors of VAP in a tertiary care hospital’ was the subject of an earlier publication; we therefore present the second investigative arm in this work. The aetiological agents of patients on mechanical ventilation (MV) were identified by standard bacteriological method. The susceptibility pattern was evaluated by Kirby-Bauer disc diffusion method. Extended spectrum beta lactamase (ESBL) testing was performed by combination disc method, and metallo-beta lactamase (MBL) testing was performed by EDTA disk synergy test (EDS).Results
Late-onset VAP was associated with Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli, while early-onset VAP was commonly caused by members of Enterobacteriaceae, Candida albicans and Staphylococcus aureus. 72.2 per cent of VAP patients had monomicrobial and 27.8 per cent had polymicrobial infection. Out of the 24 isolates obtained from patients with VAP, seven (29.2 per cent) were MDR pathogens. ESBL and MBL production was detected in 40 per cent and 20 per cent of Klebsiella pneumoniae isolated in our study. Around 50 per cent of isolates associated with late-onset VAP were MDR, while 22.2 per cent isolates obtained from patients with earlyonset VAP were MDR.Conclusion
VAP is a nosocomial pneumonia that is common among ventilated patients. The aetiological agents vary from common organisms to MDR pathogens that are difficult to treat. A proper knowledge of MDR pathogens and early isolation followed by prevention of prolonged antibiotic therapy can reduce the mortality of late onset VAP. 相似文献87.
88.
The National Toxicology Program (NTP) is using the Comet assay to evaluate genotoxic potential, and is investigating the integration of this assay into repeat-dose toxicity studies. To reduce sample-to-sample variability, address logistical concerns associated with evaluating multiple tissues from many animals, and accommodate sample collection at geographically distant testing facilities, tissue samples collected for Comet analysis by the NTP are routinely flash-frozen in liquid nitrogen and stored in a -80°C freezer until evaluation. To compare data obtained from frozen tissues to data from freshly isolated tissues, we conducted a dose-response study in male Sprague Dawley rats. Rats (5 per treatment group) were administered ethyl methanesulfonate (EMS; 0, 25, 50, 100, or 200 mg/kg) by gavage twice at an interval of 21 hr; blood, liver, stomach, and colon tissues were harvested 3 hr after the second treatment. Single-cell preparations from each of the four tissues were put into Hank's balanced salt solution with 10% fresh dimethyl sulfoxide. One aliquot of each tissue preparation was used for immediate analysis, while additional aliquots were flash-frozen in liquid nitrogen and stored in a -80°C freezer for 1 or 8 weeks. One set of 8-week frozen samples was shipped roundtrip via air courier from Research Triangle Park, NC to Rochester, NY prior to analysis. For all four tissues, results from frozen, nontransported samples showed a similar dose-response pattern for EMS-induced genotoxicity. We also demonstrated that for three tissues (blood, liver, stomach), air transport did not alter the sensitivity of the Comet assay for detecting DNA damage. 相似文献
89.
Teleradiology is an established fact in developed countries. It has been the subject of intense professional and even legal debate in recent years because the quality of care and the role of the radiologist as a medical specialist are at stake. The opportunities and the dangers involved in teleradiology are discussed in this article. The use of teleradiology in certain circumstances in the emergency department can result in significant benefits when done right; however, it is evident that poorly implemented teleradiology services can lead to significant decreases in the quality of care (for example when the aim is to provide a low cost reporting service through outsourcing).Radiologists must use their knowledge and collaboration to ensure that they have the main role in the design, management, and performance of teleradiology services. The stance of our scientific societies together with the legal and regulatory frameworks must be the pillars that support teleradiology as a medical act. 相似文献
90.