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11.
Orthotopic liver transplantation (OLT) is now a definitive treatment option for most cases of endstage liver disease (ESLD) in children. Efforts now focus on active supportive treatment to maintain, if not improve, the patient's clinical status before OLT and to ensure normal patterns of growth and development after OLT. Malnutrition adversely affects the outcome of OLT and is probably the single area in pre-operative management where the largest potential improvement can be made. Our studies indicate significant abnormalities of protein energy metabolism and body composition in children referred for OLT. We have shown that the use of enteral formulae, enriched with branched-chain amino acids, have significant advantages. Other adjunctive therapy, such as growth hormone, is the subject of current investigation. Following transplantation, catch-up weight and growth does occur with the advent of normal liver functioning, but patients at continuing risk for undernutrition, such as those with rejection and/or chronic infection, need to be targeted for specific nutritional therapy.  相似文献   
12.
Xing S  Santerre Jp  Labow RS  Boynton EL 《Biomaterials》2002,23(17):3595-3602
Macrophages and polyethylene (PE) particulate are currently recognized as being the two common denominators in the development of chronic inflammation, periprosthetic osteolysis, and subsequent implant failure. In this study, the effect of PE particulate surface chemistry on mature human monocyte-derived macrophage (MDM) function was investigated. Virgin high-density PE (HDPE: 4-10 microm) and HDPE oxidized by irradiation, thermal and chemical treatment were characterized by FT-IR and suspended in soluble type I collagen, which was subsequently solidified on glass coverslips. Human MDMs, derived from differentiating monocytes on polystyrene for 14 days, were trypsinized and cultured on collagen-particle substrata and collagen controls for 31 days. Analysis of conditioned media collected at 24h incubation showed a significantly higher level of IL-1beta secretion in virgin HDPE over oxidized HDPE or collagen controls, and a significant inhibition of IL-6 secretion in both virgin and oxidized samples. Esterase activity was increased in the medium at a significantly higher level in the virgin HDPE versus controls with the highest activity observed in oxidized HDPE at 31 days. These results illustrate the effect of PE particle surface chemistry (oxidation) on MDM cytokine secretion and esterase activity, and highlight the need to further investigate the potential of PE surface chemistry on modulating MDM function.  相似文献   
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Perception of our own bodies is based on integration of visual and tactile inputs, notably by neurons in the brain's parietal lobes. Here we report a behavioural consequence of this integration process. Simply viewing the arm can speed up reactions to an invisible tactile stimulus on the arm. We observed this visual enhancement effect only when a tactile task required spatial computation within a topographic map of the body surface and the judgements made were close to the limits of performance. This effect of viewing the body surface was absent or reversed in tasks that either did not require a spatial computation or in which judgements were well above performance limits. We consider possible mechanisms by which vision may influence tactile processing.  相似文献   
15.
DNA microarray assay has become a useful tool for gene expression studies. Less frequent is its application to detection of viruses or diagnostics of virus diseases. Here we show design of a microscope slide-based microarray assay for simultaneous identification of several potato viruses. Different primer pairs were designed or adopted to obtain specific amplicons from six potato viruses: Potato virus A (PVA), Potato virus S (PVS), Potato virus X (PVX), Potato virus Y (PVY), Potato mop-top virus (PMTV) and Potato leaf-roll virus (PLRV). Purified viral DNA probes were spotted on a microscope slide coated with poly-L-lysine. The same primers were used for preparation of fluorochrome-labeled targets. The latter were denatured and hybridized on the microarray slide (chip). An example of simultaneous assay of two pathogens is given and possibilities of practical application of this type of assay are discussed.  相似文献   
16.
AIMS: Present study was performed to compare the dynamics of human L-type calcium current (ICa,L) flowing during rectangular voltage pulses, voltage ramps, and action potentials (APs) recorded from epicardiac and endocardiac canine ventricular cells. METHODS: ICa,L was recorded in single myocytes isolated from undiseased human hearts using the whole cell voltage clamp technique. RESULTS: The decay of ICa,L was monotonic when using rectangular pulses or endocardial APs as voltage commands, whereas the current became double-peaked (displaying a second rise and fall) during epicardial (EPI) APs or voltage ramps used to mimic EPI APs. These ICa,L profiles were associated with single-hooked and double-hooked phase-plane trajectories, respectively. No sustained current was observed during the AP commands. Kinetics of deactivation and recovery from inactivation of human ICa,L were determined using twin-pulse voltage protocols and voltage ramps, and the results were similar to those obtained previously in canine cells under identical experimental conditions. CONCLUSIONS: ICa,L can inactivate partially before and deactivate during the phase-1 repolarization of the epicardiac AP, and reopening of these channels seems to be associated with formation of the dome.  相似文献   
17.
A thought, returning again and again in hand surgery, is the immediate introduction of active motion therapy after the reconstructive operations of the flexor tendons. To the active motion an adequately strong tendon suture, to the definition of "adequately strong tendon suture" however the measurement of the pulling force, acting actually on the flexor tendons is necessary. Authors attempted to measure this pulling force during flexor tendon operations on cadaver's hand. On the basis of their measurements the maximal pulling force, that can be expected during postoperative active movement exercises with adequate circumspection, can be estimated as two kiloponds.  相似文献   
18.
PURPOSE: This is a retrospective study comparing the clinical data and morbidity of transperitoneal radical nephrectomy (TRN) and simple nephrectomy. MATERIAL AND METHODS: From 1st January, 1989 to 1st January, 1996 a total of 90 simple nephrectomies and from 1st January, 1996 to 1st August, 1999 a number of 85 TRN were performed at the Department of Urology of the Saint Stephen Hospital. The analysis of clinical data included operative time, length of analgesics, postoperative hospital stay and blood loss, as well as morbidity. RESULTS: The mean operative time for TRN was 170 min., being 95 min. for simple nephrectomy. The mean blood loss for TRN was 250 ml, and 400 ml for simple nephrectomy. There were different types of morbidity for TRN and simple nephrectomy. The complications of TRN mean minimal risk and easy correctibility. CONCLUSION: Our results demonstrate an overall clear advantage of TRN when compared to simple nephrectomy.  相似文献   
19.
The objective of this study was to determine whether magnetic resonance imaging (MRI) could reliably demonstrate fistulas and any associated mass and to see whether these findings were beneficial in the management of the fistula. Twelve consecutive patients presenting with suspected vaginal fistulas were examined prospectively with MRI, using a combination of sequences, for the presence, extent and configuration of fistulas and any associated mass. Comparison was made with CT when available. All patients underwent examination under anesthesia (EUA) and the findings compared. Of the 12 women presenting, seven had vesico-vaginal fistulas (VVF) and seven had recto-vaginal fistulas (RVF). Four women had both types of fistulas. The underlying pathology was cervical cancer (seven cases), colonic cancer (three cases), breast cancer (one case) and ovarian cancer (one case). Vaginal fistulas were unequivocally seen on MRI in eight of 10 cases with fistulas. In the two cases with a difference between the MRI and EUA findings, the MRI was interpreted as showing more than was found at EUA. In the seven women with VVF, MRI detected five of the cases. In the seven women with RVF, MRI detected all seven cases. Magnetic resonance imaging was correct in determining the presence of recurrent disease in the pelvis when an associated mass was seen (seven cases). Computer-assisted tomography was compared in 10 cases and in six cases, the results were comparable and in four cases, more information was obtained from the MRI. Magnetic resonance imaging appears to be accurate in detecting and defining complex gynecologic fistulas and should be considered the investigation of choice to aid the planning of restorative, salvage or palliative surgery.  相似文献   
20.
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