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31.
After kidney transplantation, thrombotic microangiopathy (TMA) can occur de novo or as recurrent disease. Risk factors for de novo posttransplant TMA include ischemia-reperfusion injury, immunosuppressive drugs, viral infections, acute humoral rejection, and complement gene abnormalities. Cytomegalovirus infection as a trigger for posttransplant TMA in kidney transplant recipients has only been reported in 7 cases, all of them between 4 weeks and 8 years after transplantation. We describe a new case of de novo TMA in association with cytomegalovirus infection 25 years after kidney transplantation.  相似文献   
32.
Background: In patients who sustain abdominal trauma the liver is the most frequently injured organ. Although treatment for haemodynamically unstable patients remains urgent surgery, there has been a shift of management in haemodynamacally stable patients towards non-operative management. We performed an outcome assessment of traumatic hepatic injury.

Methods: A retrospective study was performed to assess incidence, mechanisms, management and outcome of traumatic liver injury in the region of ’s-Hertogenbosch, the Netherlands, in the period 1999–2007.

Results: A total of 47 patients were identified. Thirty-six patients had blunt hepatic trauma, eleven sustained penetrating hepatic injury. In 67% (n = 24) of the blunt hepatic trauma patients the initial intention was to treat non-operatively. Yet, two patients underwent explorative laparotomy after one and two days. In the penetrating liver trauma patients, 91% (n = 10) underwent urgent surgery. In total, 31 of 47 patients were treated conservatively.

Conclusion: Blunt hepatic trauma is the most common cause of hepatic trauma. Most patients sustaining hepatic trauma can be managed conservatively at a dedicated ICU and/or surgical trauma ward.  相似文献   
33.
Background: To support safe and effective use of propofol in nonventilated children after major surgery, a model for propofol pharmacokinetics and pharmacodynamics is described.

Methods: After craniofacial surgery, 22 of the 44 evaluated infants (aged 3-17 months) in the pediatric intensive care unit received propofol (2-4 mg [middle dot] kg-1 [middle dot] h-1) during a median of 12.5 h, based on the COMFORT-Behavior score. COMFORT-Behavior scores and Bispectral Index values were recorded simultaneously. Population pharmacokinetic and pharmacodynamic modeling was performed using NONMEM V (GloboMax LLC, Hanover, MD).

Results: In the two-compartment model, body weight (median, 8.9 kg) was a significant covariate. Typical values were Cl = 0.70 [middle dot] (BW/8.9)0.61 l/min, Vc = 18.8 l, Q = 0.35 l/min, and Vss = 146 l. In infants who received no sedative, depth of sedation was a function of baseline, postanesthesia effect (Emax model), and circadian night rhythm. In agitated infants, depth of sedation was best described by baseline, postanesthesia effect, and propofol effect (Emax model). The propofol concentration at half maximum effect was 1.76 mg/l (coefficient of variation = 47%) for the COMFORT-Behavior scale and 3.71 mg/l (coefficient of variation = 145%) for the Bispectral Index.  相似文献   

34.
Michael  AS; Mafee  MF; Valvassori  GE; Tan  WS 《Radiology》1985,154(2):413-419
A retrospective review of the dynamic CT studies performed in our institution on head and neck lesions, excluding the brain, was carried out. Five basic types of density vs. time curves were obtained. Dynamic CT scanning is valuable in the differential diagnosis, management, and followup of such cases; its usefulness as an imaging modality in diagnosis and followup of hemangiomas is stressed.  相似文献   
35.
Cardiac-gated magnetic resonance (MR) imaging was performed in rats to determine the effects of manganese ethylenediaminetetraphosphonate (TP). Ten normal rats received Mn-TP in a dose of 50 mumol/kg through a tail-vein injection. Spin-echo MR images were obtained before and every 10 minutes after Mn-TP injection for 1 hour. Cardiac signal intensity (SI) increased more than 70% after Mn-TP injection and remained nearly unchanged 1 hour after injection. Myocardial T1 was 517 +/- 49 msec in eight control rats and 282 +/- 61 msec (P less than .001) in six rats 81 +/- 0 minutes after injection. Nine rats underwent occlusion of the left anterior descending coronary artery prior to MR imaging. Images were obtained before and 15, 30, and 60 minutes after Mn-TP injection. In normal myocardium, SI increased up to 82% and remained elevated for 1 hour. In ischemic myocardium, SI rose 11%, leading to a marked contrast between the two tissue zones. T1 was also different in the two regions: In normal tissue, it was 206 msec +/- 54; in ischemic tissue, 338 +/- 82 (P less than .001). With T1-weighted MR imaging, Mn-TP showed a potential for delineating the jeopardized area after acute myocardial ischemia.  相似文献   
36.
When infection of prosthetic orthopedic implants is suspected, optimal management requires accurate confirmation or exclusion of infection. The authors retrospectively studied 98 patients with possible infection who underwent scanning with indium-111-labeled white blood cells (WBCs) and subsequently underwent surgery within 14 days. At surgery, 50 patients had infections, as determined by means of culture or histologic results. The diagnostic accuracy of In-111 scanning was compared with that of plain radiography, arthrography, three-phase bone scanning, and various clinical and laboratory findings classically associated with infection. Positive findings on In-111 WBC scans and elevated erythrocyte sedimentation rates were found to be the most predictive variables in the diagnosis of septic prostheses (P less than or equal to .001 and P less than or equal to .002, respectively). Likelihood ratio analysis more clearly demonstrated the superiority of In-111 WBC scanning, with positive and negative scans yielding likelihood ratios of 5.0 and 0.16, respectively.  相似文献   
37.
38.
Metabolic Brain Disease - In Part I of this Review we evaluated the scientific evidence for a Metabolic Model of multiple sclerosis (MS). Part II outlines the implementation of an adaptive...  相似文献   
39.
Noninvasive assessment and monitoring of the pulmonary circulation.   总被引:3,自引:0,他引:3  
In pulmonary vascular disease, changes in the pulmonary vascular bed will lead to altered pulmonary haemodynamics. This review describes the application of several physiological principles to measure these changes noninvasively by means of novel techniques. Flow characteristics of blood through the pulmonary vascular bed alter in pulmonary vascular disease. Recent developments in magnetic resonance imaging and computed tomography make it possible to visualise and quantify these abnormal flow patterns. Information regarding pulmonary perfusion can also be obtained by measuring the electrical impedance changes in the lung by electrical impedance tomography. A more indirect approach to measure the pulmonary blood flow is the measurement of the absorption of acetylene, a perfusion limited gas. Information on the pulmonary vascular bed can also be obtained by the measurement of exhaled products of the pulmonary vascular endothelium, such as nitric oxide. Although all the techniques described offer new ways to diagnose or monitor pulmonary vascular disease, clinical data on these techniques are limited. Further improvement and evaluation of the clinical value of these techniques are therefore obligatory before they can be used in clinical practice.  相似文献   
40.
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