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991.
Changes in the levels of urea cycle enzymes and polyamine metabolism in the liver of rats treated with alpha-naphthylisothiocyanate (ANIT), an inducer of experimental cholestasis, were studied. Activities of arginase increased approximately two-fold compared to the control values during the period of 24-72 hours after oral administration of ANIT (100 mg/kg), while activities of ornithine carbamyltransferase and ornithine aminotransferase decreased. The activity of ornithine decarboxylase was elevated by approximately 20- and 10-fold at 12 and 60 hours, respectively, after ANIT administration. Putrescine concentration doubled 24-48 hours after the ANIT administration, but spermidine level rose more slowly and reached the level of 1.5-fold of the control level in 36-72 hours. Spermine concentration decreased initially but increased in 96 hours. These results suggest that the increased activity of urea cycle accounts for the increase in the ornithine content and that the putrescine and spermidine acts as the initiator of recovery of the liver damaged by ANIT treatment.  相似文献   
992.
993.
Ciclesonide is an onsite-activated inhaled corticosteroid (ICS) for the treatment of asthma. This study compared the efficacy, safety and effect on quality of life (QOL) of ciclesonide 160 microg (ex-actuator; nominal dose 200 microg) vs. budesonide 400 microg (nominal dose) in children with asthma. Six hundred and twenty-one children (aged 6-11 yr) with asthma were randomized to receive ciclesonide 160 microg (ex-actuator) once daily (via hydrofluoroalkane metered-dose inhaler and AeroChamber Plus spacer) or budesonide 400 microg once daily (via Turbohaler) both given in the evening for 12 wk. The primary efficacy end-point was change in forced expiratory volume in 1 s (FEV1). Additional measurements included change in daily peak expiratory flow (PEF), change in asthma symptom score sum, change in use of rescue medication, paediatric and caregiver asthma QOL questionnaire [PAQLQ(S) and PACQLQ, respectively] scores, change in body height assessed by stadiometry, change in 24-h urinary cortisol adjusted for creatinine and adverse events. Both ciclesonide and budesonide increased FEV1, morning PEF and PAQLQ(S) and PACQLQ scores, and improved asthma symptom score sums and the need for rescue medication after 12 wk vs. baseline. The non-inferiority of ciclesonide vs. budesonide was demonstrated for the change in FEV1 (95% confidence interval: -75, 10 ml, p = 0.0009, one-sided non-inferiority, per-protocol). In addition, ciclesonide and budesonide showed similar efficacy in improving asthma symptoms, morning PEF, use of rescue medication and QOL. Ciclesonide was superior to budesonide with regard to increases in body height (p = 0.003, two-sided). The effect on the hypothalamic-pituitary-adrenal axis was significantly different in favor of ciclesonide treatment (p < 0.001, one-sided). Both ciclesonide and budesonide were well tolerated. Ciclesonide 160 microg once daily and budesonide 400 microg once daily were effective in children with asthma. In addition, in children treated with ciclesonide there was significantly less reduction in body height and suppression of 24-h urinary cortisol excretion compared with children treated with budesonide after 12 wk.  相似文献   
994.
Previously, we reported that transgenic mice overexpressing endothelin-1 in astrocytes showed more severe neurological deficits and increased infarct after transient focal ischemia. In those studies, we also observed increased level of aldose reductase (AR), the first and rate-limiting enzyme of the polyol pathway, which has been implicated in osmotic and oxidative stress. To further understand the involvement of the polyol pathway, the mice with deletion of enzymes in the polyol pathway, AR, and sorbitol dehydrogenase (SD), which is the second enzyme in this pathway, were challenged with similar cerebral ischemic injury. Deletion of AR-protected animals from severe neurological deficits and large infarct, whereas similar protection was not observed in mice with SD deficiency. Most interestingly, AR(-/-) brains showed lowered expression of transferrin and transferrin receptor with less iron deposition and nitrotyrosine accumulation. The protection against oxidative stress in AR(-/-) brain was also associated with less poly(adenosine diphosphate-ribose) polymerase (PARP) and caspase-3 activation. Pharmacological inhibition of AR by Fidarestat also protected animals against cerebral ischemic injury. These findings are the first to show that AR contributes to iron- and transferrin-related oxidative stress associated with cerebral ischemic injury, suggesting that inhibition of AR but not SD may have therapeutic potential against cerebral ischemic injury.  相似文献   
995.
996.
997.
Throughout most medical careers the practical aspects of dealingwith tracheostomies are an ignored but simultaneously fearedaspect of patient care. They are generally regarded as someoneelse's business, right up to the point when a disaster occurs.Even when the patient is breathless and needing help many healthpractitioners of all types fear to step in and execute  相似文献   
998.
Kniearthrodesen     
When arthrodesis of the knee is indicated, the operative procedure selected for fixation depends on the condition of the soft tissues, the bone stock, whether infection is present, and the age of the patient and his or her capacity for partial weight-bearing. In young patients with no infection or soft tissue problems, when adequate bone stock is present compression plating or the use of an intramedullary nail is possible and allows stable fixation. Soft tissue problems with defect(s) or infection are a good indication for the use of an external fixator. The most common indication for knee arthrodesis is a failed total knee prosthesis that has become infected. Deficient bone stock with osteopenic bone or a defect after failed total knee arthroplasty are problems that can be solved by the use of modular fusion nail systems, especially in older patients. These systems are more comfortable for the patient than external fixation devices and allow early full weight-bearing.  相似文献   
999.
Bone morphogenetic proteins (BMPs) are bone growth factors, which regulate bone formation during fetal development and bone repair after injury in postfetal life. Since 1992 BMP-7 has been produced by recombinant technique (rhBMP-7). Numerous animal models and clinical trials have shown that rhBMP-7 can induce de novo bone formation in segmental defects of bones and in cases of nonunion. Since 2001 rhBMP-7 has been approved for treatment of tibial nonunion in Europe. The effect of rhBMP-7 is comparable to the clinical and radiological results achieved with bone autografts. The problem of donor site morbidity (which occurs in up to 20% of all cases) is eliminated by the use of BMP-7. Long-term results and experience in clinical practice are not yet available.  相似文献   
1000.
A distinction is made between intra- and postoperative complications. Intraoperative complications embrace incorrect repositioning, a poor overall view and injuries to organs in the neck (the carotic artery or the oesophagus). These can be avoided by precise repositioning preoperatively and adjustment of the dens in both planes with the aid of two image converters, and preoperative marking of the orientation of the screws. Postoperative complications can take the form of pseudoarthrosis and/or progressive myelopathy. Pseudarthrosis is stabilised with the aid of transarticular screw fixation after Magerl in combination with fusion using the Gallie or the Brooks technique. Progressive myelopathy frequently has its roots in inadequate repositioning resulting in restriction of the diameter of the spinal cord.  相似文献   
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