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91.
Tanax or T-61, a euthanasia solution commonly used in veterinary medicine, has been often involved in suicide attempts (humans) and malicious intoxications (animals). For forensic reasons, the identification of one or more of the three components (embutramide, mebenzonium iodide, and tetracaine hydrochloride) of Tanax is needed to confirm the hypothesis of intoxication. This study was performed with new high-performance liquid chromatographic and gas chromatographic-mass spectrometric methods to identify embutramide in biological matrices (blood, liver, kidney) from different animal species. The good sensitivity and specificity of both methods recommend their use in toxicological analysis in both human and veterinary medicine.  相似文献   
92.
We report a case of Fabry's disease where stabilization of progressive cardiac involvement was recorded in a 29-yr-old Caucasian man, to our knowledge, for the first time by ultrasonic tissue characterization echocardiography after 1 yr of successful renal transplantation. Three echocardiographic evaluations have been made: the first 3 months before, the second 6 months after, and the third 1 yr after kidney transplantation. The myocardial structural damage - evaluated by integrated backscatter index - shows a persistence of the impairment of intrinsic myocardial contractility at septum level, probably due to coexistent hypertensive status, which is able to induce per se alterations of myocardial textural parameters. On the other hand, the cyclic variation index at posterior free wall, which is less dependent on strictly hemodynamic factors than the septum, appears quite normal at the third observation. These data could reflect the improvement of the ultrastuctural myocardial findings in relation to renal transplantation, which could correct not only renal failure but also the enzymatic deficiency by replacement of alpha-galactosidase A through the transplanted kidney.  相似文献   
93.
Objective To determine the incidence of cardiac tamponade related to peripherally inserted central catheters in newborns weighing less than 1,500 g during the past 8 years and to provide guidelines in order to avoid death due to this complication.Design Retrospective case review.Setting Tertiary level neonatal intensive care unit.Patients and participants Retrospective study of a total of 280 peripherally inserted central catheters positioned in 258 preterm newborns.Measurements and results Five cardiac tamponades were observed, giving an incidence of 1.8%. Data from our cases included clinical presentation and outcome, biochemical evaluation of pericardial fluid, days until diagnosis, central catheters characteristics, insertion site and tip placement site.Intervention Two of the infants did not respond to resuscitation measures including cardiac massage and the administration of epinephrine. Post-mortem examination revealed the intrapericardial accumulation of protein and lipid alimentation solution. The other three patients were successfully resuscitated by timely pericardiocentesis. All five infants had routinely performed serial radiographs and cardiac color Doppler ultrasonography that showed correct catheter tip placement.Conclusions The incidence of cardiac tamponade could be reduced by following specific guidelines. The possibility of tamponade must be kept in mind during the resuscitation of any preterm infant with a peripherally inserted central catheter in place who develops symptoms of shock or sudden bradycardia. Our experience shows that even preterm infants with cardiac tamponade can be successfully resuscitated by timely pericardiocentesis in most cases.  相似文献   
94.
In the past years, assessment of cardiac function has become possible through the analysis of intracardiac flow dynamics, performed noninvasively using phase‐contrast cardiac magnetic resonance and contrast and noncontrast ultrasound techniques. From 2013 to 2019, 9 echocardiographic investigations have considered 215 patients with cardiac resynchronization therapy (CRT) as a model for assessing flow dynamics within the left ventricle. Preliminary results have been reported about the acute hemodynamic effects of CRT and programming of the CRT device, showing the potential of an approach based on analysis of intracardiac flows. At present, there are only scarce data on the capability of intracardiac flow dynamics to predict LV remodeling after CRT and no information on clinical outcome prediction. Future investigations should be aimed at clarifying the mechanisms and impact of maladaptive intracardiac vortex dynamics on progressive LV remodeling as well as the prognostic meaning of implanted CRT device based on cardiac flow analysis.  相似文献   
95.
OBJECTIVE: To investigate the acute effects of low-dose caffeine and aminophylline on cerebral blood flow in preterm infants, using both near-infrared spectroscopy (NIRS) and cerebral Doppler ultrasonography. METHODS: Preterm infants with a gestational age of <32 weeks and birth weight of <1,500 g were randomized to receive either caffeine or aminophylline treatment for apnea of prematurity. The study period went from 30 min before to 60 min after the administration of the maintenance dose of pure caffeine (2.5 mg/kg once a day) or aminophylline (1.25 mg/kg twice a day). NIRS was used to measure changes in oxygenated hemoglobin (O(2)Hb), deoxygenated hemoglobin (HHb), oxidized-reduced cytochrome aa3 (CtOx), and mean cerebral oxygen saturation (SmO(2) = O(2)Hb/total Hb). Changes in cerebral blood volume (DeltaCBV) after caffeine or aminophylline administration were calculated. Cerebral blood flow velocity (CBV) in the pericallosal artery was evaluated by cerebral Doppler ultrasounds. RESULTS: Data collected by NIRS and cerebral Doppler ultrasounds did not show significant differences before and after caffeine treatment. We observed a significant increase in O(2)Hb and HHb concentration and in CBV at 30 min after the infusion of aminophylline, which tended to return to baseline at the end of the study period. CONCLUSION: Caffeine does not significantly affect brain hemodynamics, while aminophylline induces a significant transient increase in O(2)Hb and HHb concentration and CBV.  相似文献   
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To clarify the possible role of TNF and IL-1 in endotoxic shock, the lethality of rTNF (human and murine) and IL-1 in adrenalectomized mice was studied. Adrenalectomy, which has long been known to increase the susceptibility to endotoxin, rendered mice susceptible to TNF and IL-1 in terms of mortality. The lethality of endotoxin, TNF, or IL-1 was totally prevented by pretreatment with dexamethasone (minimal effective dose, 0.3 mg/Kg) but not by ibuprofen (10 mg/Kg).  相似文献   
100.
The mechanisms at the origin of heterogeneous carbapenem resistance levels observed among Acinetobacter baumannii isolates collected in 2005 in a large University Hospital of Rome, Italy, were investigated. These isolates were related and possessed similar plasmids carrying the carbapenem-hydrolyzing oxacillinase gene bla(OXA-58) but showed variable levels of resistance to carbapenems. Analysis of sequences surrounding the bla(OXA-58) gene showed genetic variability, with the presence in several isolates of multiple copies of the bla(OXA-58) gene; this extra copy number was likely related to an IS26-mediated transposition or recombination process.  相似文献   
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