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61.
IGF-1在成骨样细胞增殖中的作用及与钾离子通道的关系   总被引:1,自引:0,他引:1  
目的 :研究胰岛素样生长因子 - 1(IGF - 1)促大鼠成骨样肉瘤细胞 (UMR10 6 )增殖作用及与钾离子通道活动的关系。方法 :采用磺基罗丹明 (SRB)染色法观察细胞增殖并用膜片钳技术记录细胞膜钾离子通道电流的变化。同时用3 H -TdR掺入测定DNA合成的改变。结果 :IGF - 1可以明显地促进UMR10 6细胞的增殖 ,且使3 H -TdR掺入率增加 93.5 7%。在含有生长因子IGF - 1(10 -8M)的培养液中培养 12h后 ,钾通道电流比对照有明显增加 ,而且用钾通道阻断剂后 ,3 H -TdR掺入率下降。结论 :IGF - 1可促进大鼠成骨样肉瘤的DNA合成和细胞增殖。且细胞膜钾通道的活动与此促增殖活动密切相关  相似文献   
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PurposeTo define how much of renal function was determined by the preserved renal parenchymal volume and the ischemic insult during partial nephrectomy (PN) long after surgery.MethodsWe analyzed the data of 530 consecutive patients who had undergone PN. For all patients, renal function was measured preoperatively and again at 3 postoperative months, then annually using 99mTc-diethylenetriaminepentaacetic acid renal scan. Perioperative variables potentially affecting the long-term ipsilateral glomerular filtration rate (GFR) and their time-varying contribution were assessed using a linear mixed model.ResultsThe mean preoperative ipsilateral GFR was 42.9 ml/min, which decreased by 27.3% at 3 months but began to recover thereafter continuing until 4 years (Δ% GFR at 1, 2, 3, 4, and 5 years: 22.3%, 18.5%, 14.7%, 10.0%, and 9.6%, respectively). Parenchymal volume reduction and ischemic time were significantly associated with postoperative ipsilateral GFR throughout observation period unvarying with time. Diabetes and proteinuria were not significant determinants of ipsilateral function at 3 months but became significant at 5 years. In multivariate analysis regarding recovery slope, volume reduction (β = ?0.026, SE 0.006, P < 0.0001), preoperative ipsilateral GFR (β = ?0.021, SE 0.007, P = 0.0012), proteinuria (β = ?0.942, SE 0.372, P = 0.0116), and diabetes (β = ?0.396, SE 0.197, P = 0.0447) were independently significant.ConclusionIpsilateral renal function continued to improve until 5 years after PN. Parenchymal volume loss was the major determinant and its impact on long-term ipsilateral renal function remained constant while ischemic time affected early GFR reduction with its impact diminishing over time. Patient-related factors including diabetes and proteinuria gained significance over time and became independent determinants of recovery slope.  相似文献   
64.
Introduction: Computed tomography (CT) can be used to assess bone status with measurement of Hounsfield unit (HU). The objective of this study was to evaluate whether HU of muscle might be associated with parameters of bone and muscle status. Methods: We reviewed 71 women aged over 50 yr of age who had distal radius fracture and underwent CT evaluation of affected wrist. We assessed HUs of forearm flexor muscles (flexor digitorum superficialis) and thenar muscles and bone HUs at the capitate and the ulnar head. Other parameters included femur neck and lumbar bone mineral density (BMD), upper extremity lean mass, hand grip strength, and muscle fiber cross-sectional area. We performed correlation analyses to determine associations between variables. Results: Thenar and forearm muscle HUs were significantly correlated with each other, but not with other parameters. HUs of the capitate and ulnar head were positively correlated with femur neck and lumbar BMDs and inversely correlated with age. Ulnar head HU was positively correlated hand grip strength. Conclusions: HUs of forearm and thenar muscles did not show significant correlations with bone or muscle parameters, although bone HUs correlated well with bone mineral densities. These results support the opportunistic use of CT for evaluating bone fragility. Clinical usefulness of muscle HU measurement needs further studies.  相似文献   
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BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.  相似文献   
67.
This study investigated the risk of insomnia and hypnotics use among emergency physicians. This cross-sectional study recruited physicians working in Taiwanese hospitals in 2015 and the general population as the participants. Data from 1,097 emergency physicians obtained from the National Health Insurance Research Database were grouped into the case group, whereas 14,112 nonemergency physicians and 4,388 people from the general population were categorized into the control groups. This study used logistic regression and conditional logistic regression to compare the risks of insomnia between emergency and nonemergency physicians and between emergency physicians and the general population, respectively. The prevalence of insomnia among emergency physicians, nonemergency physicians and general population was 5.56%, 4.08%, and 1.73%, respectively. Compared with nonemergency physicians and the general population, emergency physicians had a significantly higher risk of insomnia. The proportions of emergency physicians, nonemergency physicians, and general population using hypnotics were 19.96%, 18.24%, and 13.26%, respectively. Among emergency physicians who used hypnotics, 49.77%, 25.57%, and 24.66% used only benzodiazepines, only nonbenzodiazepines, and both benzodiazepines and nonbenzodiazepines, respectively. Nonpharmacological interventions to improve insomnia and reminder of safe use of hypnotics to emergency physicians can serve as references for hospitals in developing health-promoting activities.  相似文献   
68.
目的:观察普罗布考(probucol)对血管平滑肌细胞(VSMCs)核因子kB(NF-kB)活性的调控作用,以探讨probucol在动脉粥样硬化(AS)和经皮腔内冠状动脉成形术后再狭窄(RS)防治中的某些可能的作用机制。方法:采用电泳迁移位移测定法观察probucol对VSMCsNF-kB活性的影响。结果:H2O2或胎牛血清(NCS)处理VSMCs72h后,NF-kB活性均明显增强;而加入100umol/Lprobucol后,NF-kB活性受到部分抑制,抑制率分别为37.1%和14.8%。结论:Probucol抑制NCS、H2O2诱导的VSMCsNF-kB的活性,可能是其临床有效防治RS及AS的作用机制之一。  相似文献   
69.
采用溶剂萃取-化学处理-柱层析相结合的预处理分离程序、色-质联用和色-红联用结合色谱保留值的定性方法,分析研究了内蒙东胜煤快速加氢热解焦油的化学成分和结构,推测鉴定出200多种化合物,并对具有代表性的19种多环芳烃进行了定量分析,讨论了快速加氢热解焦油化学成分的结构特征。  相似文献   
70.
目的 观察联用川芎嗪(LT)和前列素(PGE4)治疗慢性肺源性心脏病(肺心病)急性发作期患者的临床疗效。方法 105例肺心病急性发作期患者随机分为治疗组(54例)和对照组(51例),治疗组采用LT联合PGE1治疗;对照组采用单纯PGE1治疗。2组患者于治疗后10d测定血液流变学指标并进行疗效判定。结果 治疗组显效率(59.26%)明显高于对照组(39.22%),2组比较具有显著差异(P〈0.05)  相似文献   
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