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41.
Human leukocyte antigen (HLA) associations have been frequently reported in childhood steroid-responsive nephrotic syndrome (SRNS) in other populations. The aim of this study was to characterize the immunogenetic background of Singaporean Chinese patients with childhood SRNS. We determined the HLA class I (HLA-A* and HLA-B*) as well as class II (HLA-DRB1*, HLA-DQB1*) gene polymorphisms using the polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO) technique, in patients with SRNS (n=64) and normal controls (n=236 for HLA-A*, n=80 for HLA-B*, HLA-DRB1* and HLA-DQB1*). The frequency of HLA-A*11 allele was significantly higher in the SRNS patients compared to controls (78.1% vs 54.2%, respectively; relative risk, RR=3.01, Pc=0.011). However, there was no significant difference in the allele frequencies of HLA-B*, HLA-DRB1* and HLA-DQB1* between the SRNS patients and controls, unlike that in previous studies. Our data suggest that the immunogenetic background of Singaporean Chinese with childhood SRNS was different from that in other populations. As HLA-A*11 has been strongly associated with other autoimmune diseases, it is conceivable that the HLA-A*11-specific motif may play a role in the development of the abnormal T-cell-mediated immune response that may be responsible for triggering the proteinuria seen in SRNS. Received: 24 April 2001 / Revised: 14 November 2001 / Accepted: 18 November 2001  相似文献   
42.
As current low back pain (LBP) guidelines do not specifically advocate walking as an intervention, this review has explored for the effectiveness of walking in managing acute and chronic LBP. CINAHL, Medline, AMED, EMBASE, PubMed, Cochrane and Scopus databases, as well as a hand search of reference lists of retrieved articles, were searched. The search was restricted to studies in the English language. Studies were included when walking was identified as an intervention. Four studies met inclusion criteria, and were assessed with a quality checklist. Three lower ranked studies reported a reduction in LBP from a walking intervention, while the highest ranked study observed no effect. Heterogeneity of study design made it difficult to draw comparisons between studies. There is only low–moderate evidence for walking as an effective intervention strategy for LBP. Further investigation is required to investigate the strength of effect for walking as a primary intervention in the management of acute and chronic LBP.  相似文献   
43.
This study reviewed the 18-year experience of acute dialysis in the pediatric intensive care unit, in order to identify factors that could predict outcome, and to determine whether newer modalities of acute dialysis have influenced this outcome. Sixty-six children (ages 1 day to 19 years) received acute dialysis from May 1980 to April 1998. Factors predicting outcome were analyzed using univariate and Cox regression analysis. Modality of dialysis in the first 15 years was exclusively peritoneal dialysis, with a mortality of 63.9%. However, in the last 3 years, with increasing patient numbers, continuous hemodiafiltration (CHDF) was the modality of choice (56.7%), with a mortality of 73.3%. Univariate analysis showed that age <1 year, coma, acute tubular necrosis, disseminated intravascular coagulopathy, assisted ventilation, and hypotension were associated significantly with poor outcome (P<0.05). Cox regression analysis revealed that mortality was significantly higher in patients on mechanical ventilation (RR 5.96, 95% CI 1.82–19.50), or with age <1 year (RR 2.00, 95% CI 1.08–3.73). In conclusion, despite the increasing use of CHDF over the last 3 years, there was no significant improvement in mortality, probably related to the fact that more critically ill patients were dialyzed. Received: 21 March 2000 / Revised: 12 October 2000 / Accepted: 19 October 2000  相似文献   
44.
Published literature on fracture in dialysis patients seldom addressed the effect of co‐morbidity and malnutrition. In this study, we reported the incidence and risk factors for fracture in peritoneal dialysis patients. Peritoneal dialysis patients who had fractures between 2006 and 2011 were recruited. Demographic data, details of fracture, Charlson Co‐morbidity Index (CCI) and biochemical parameters were also collected. Non‐fracture controls, matched for age, gender and duration of dialysis, were also recruited at ratio 1:1 for fracture risk analysis. The incidence of fracture was 1 in 37 patient‐years. The commonest site of fracture was neck of femur (n = 16, 55.2%). Twenty‐four patients (82.8%) developed fracture after slip and fall injury. Eight out of 17 self‐ambulatory patients (47.1%) became non‐ambulatory after fracture. Infection was the commonest complication during hospitalization. Univariant analysis demonstrated high CCI (P = 0.001), hypoalbuminaemia (P < 0.001), loss of self autonomy (P = 0.006) and non‐ambulatory state (P = 0.011) significantly associated with increased fracture risk. However, only CCI (odds ratio (OR) 1.373, P = 0.028) and albumin (OR 0.893, P = 0.025) increased fracture risk significantly on multivariant analysis. Bone profile and parathyroid hormone were not significant risk factors. To conclude, fracture associated with adverse outcome in peritoneal dialysis patients. High CCI score and hypoalbuminaemia significantly increase risk of fracture.  相似文献   
45.
The standard treatments for men with lower urinary tract symptoms (LUTS) range from watchful waiting to medical and finally surgical intervention. However, the role of self-management interventions such as education and reassurance, lifestyle modification and behavioural changes has not been formally investigated, although they are widely advocated and utilised for LUTS. Self-management interventions are well established in other chronic diseases such as diabetes, arthritis and asthma. These interventions, if successfully organised within a structured program for LUTS, could improve patient outcomes as well as reduce the economic burden of LUTS treatment, by replacing or augmenting other treatments. Recent studies showing that long-term urodynamic and symptomatic deterioration of LUTS is minimal suggest that this is a safe and valid treatment option. This is supported by a recent pilot study of a LUTS self-management program which showed significant improvements in I-PSS and frequency–volume parameters. The results of a recently completed randomised controlled trial are awaited.  相似文献   
46.
INTRODUCTIONNear-peer teaching is gaining popularity as a teaching modality, as it improves the learner’s understanding, is targeted at an appropriate level and promotes familiarisation. This study was initiated to evaluate the effectiveness of incorporating near-peer instruction into simulation-based training within a junior residency programme.METHODS42 first-year residents from an internal medicine junior residency programme were recruited. Participants underwent a simulation-based training programme conducted over five weeks. Each week involved either an emergency or acute clinical scenario. A structured questionnaire was administered prior to and after the course to compare participants’ perceived knowledge, experience and confidence in managing the clinical scenarios.RESULTSIn our study, 83% of participants agreed/strongly agreed that the scenarios were realistic. There were improvements in perceived knowledge, experience and confidence after the course. The greatest improvement was seen for experience (post-simulation: median 7.00 [interquartile range (IQR) 6.00‒8.00] vs. pre-simulation: median 5.00 [IQR 3.00–6.25]). 65% of participants were keen to help with future training.CONCLUSIONNear-peer simulation training was found to be a viable and valuable method of instruction for first-year residents for increasing experience, instilling confidence and improving perceived knowledge. Integration of such programmes within medical education curricula shows good promise of continuity, with many first-year residents inspired to organise subsequent sessions.  相似文献   
47.

Background

The liver sinusoidal capillaries play a pivotal role in liver regeneration, suggesting they may be beneficial in liver bioengineering. This study isolated mouse liver sinusoidal endothelial cells (LSECs) and determined their ability to form capillary networks in vitro and in vivo for liver tissue engineering purposes.

Methods and results

In vitro LSECs were isolated from adult C57BL/6 mouse livers. Immunofluorescence labelling indicated they were LYVE-1+/CD32b+/FactorVIII+/CD31?. Scanning electron microscopy of LSECs revealed the presence of characteristic sieve plates at 2 days. LSECs formed tubes and sprouts in the tubulogenesis assay, similar to human microvascular endothelial cells (HMEC); and formed capillaries with lumens when implanted in a porous collagen scaffold in vitro. LSECs were able to form spheroids, and in the spheroid gel sandwich assay produced significantly increased numbers (p?=?0.0011) of capillary-like sprouts at 24 h compared to HMEC spheroids. Supernatant from LSEC spheroids demonstrated significantly greater levels of vascular endothelial growth factor-A and C (VEGF-A, VEGF-C) and hepatocyte growth factor (HGF) compared to LSEC monolayers (p?=?0.0167; p?=?0.0017; and p?<?0.0001, respectively), at 2 days, which was maintained to 4 days for HGF (p?=?0.0017) and VEGF-A (p?=?0.0051). In vivo isolated mouse LSECs were prepared as single cell suspensions of 500,000 cells, or as spheroids of 5000 cells (100 spheroids) and implanted in SCID mouse bilateral vascularized tissue engineering chambers for 2 weeks. Immunohistochemistry identified implanted LSECs forming LYVE-1+/CD31? vessels. In LSEC implanted constructs, overall lymphatic vessel growth was increased (not significantly), whilst host-derived CD31+ blood vessel growth increased significantly (p?=?0.0127) compared to non-implanted controls. LSEC labelled with the fluorescent tag DiI prior to implantation formed capillaries in vivo and maintained LYVE-1 and CD32b markers to 2 weeks.

Conclusion

Isolated mouse LSECs express a panel of vascular-related cell markers and demonstrate substantial vascular capillary-forming ability in vitro and in vivo. Their production of liver growth factors VEGF-A, VEGF-C and HGF enable these cells to exert a growth stimulus post-transplantation on the in vivo host-derived capillary bed, reinforcing their pro-regenerative capabilities for liver tissue engineering studies.
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