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81.
82.
In chronic myeloid leukaemia, CD34(+) stem/progenitor cells appear resistant to imatinib mesylate (IM) in vitro and in vivo. To investigate the underlying mechanism(s) of IM resistance, it is essential to quantify Bcr-Abl kinase status at the stem cell level. We developed a flow cytometry method to measure CrkL phosphorylation (P-CrkL) in samples with <10(4) cells. The method was first validated in wild-type (K562) and mutant (BAF3) BCR-ABL(+) as well as BCR-ABL(-) (HL60) cell lines. In response to increasing IM concentration, there was a linear reduction in P-CrkL, which was Bcr-Abl specific and correlated with known resistance. The results were comparable to those from Western blotting. The method also proved to be reproducible with small samples of normal and Ph(+) CD34(+) cells and was able to discriminate between Ph(-), sensitive and resistant Ph(+) cells. This assay should now enable investigators to unravel the mechanism(s) of IM resistance in stem cells.  相似文献   
83.
There is increasing evidence that the assessment of eosinophilic airway inflammation using induced sputum and measurement of airway hyperresponsiveness provides additional, clinically important information concerning asthma control. The aim of this study was to directly compare the effects of different treatments on these markers in patients with asthma and persistent symptoms, despite the use of low-dose inhaled corticosteroids. A double-blind four-way crossover study was performed, which compared a 1-month treatment with budesonide 400 mug b.i.d., additional formoterol, additional montelukast and placebo in 49 patients with uncontrolled asthma despite budesonide 100 mug b.i.d., with each treatment separated by a 4-week washout period. The change in sputum eosinophil count with formoterol (2.4 to 3.8% change, 0.6-fold reduction, 95% confidence interval (CI) 0.5-0.9) differed significantly from placebo (2.8 to 2.5% change, 1.1-fold reduction, 95% CI 0.7-1.6) and high-dose budesonide (2.7 to 1.6% change, 1.6-fold reduction, 95% CI 1.2-2.2). The effects of montelukast did not differ from placebo. The changes in methacholine airway responsiveness were small and did not differ between treatments. High-dose budesonide had the broadest range of beneficial effects on other outcomes, including symptom scores, morning peak expiratory flow and forced expiratory volume in one second. In conclusion, treatment given in addition to low-dose inhaled corticosteroids results in modest benefits. Formoterol and high-dose budesonide have contrasting effects on eosinophilic airway inflammation.  相似文献   
84.
85.
目的:评价东部身体-智力-精神(EBMS)群体干预对进行体外受精(IVF)的中国妇女焦虑缓解的作用。设计:随机对照研究。机构:三级辅助生殖机构。受试者:227例接受第1个IVF周期治疗的妇女。干预:干预组(n=69)接受4次EBMS群体咨询,而对照组(n=115)无任何干预。主要观察指标:状态-特质焦虑问卷。结果:与对照组相比,干预组在干预后状态焦虑平均分显著下降。每组移植同样数目的卵子,但干预组没有明显更高妊娠率的倾向。  相似文献   
86.
87.
[目的]探讨降钙素对已行人工假体植入骨质疏松模型免的假体无菌性松动防治作用的实验研究。[方法]将30只假体植入模型的骨质疏松症兔随机分成实验组和对照组,各15只。实验组给予鲑鱼降钙素治疗(6U/kg,肌注,隔日1次),而对照组给予等量的生理盐水肌注,持续治疗半年。两组均分别于术前、术后4、8、12和24周检测假体周围感应区(ROI)骨密度(BMD);于术前及术后4、12、24周行血清骨代谢指标检测:骨特异性碱性磷酸酶(BALP)、骨钙素(BGP)、抗酒石酸酸性磷酸酶-5b(TRAP-5b);所有动物于术后24周处死,分别行假体拔出实验与扭转实验测定和假体周围骨组织形态计量学分析。[结果]术后24周,实验组假体周围局部感兴趣区BMD增加近5%,而对照组假体周围局部感兴趣区BMD下降了6%,两组比较有显著性差异(P〈0.01);骨代谢指标中,术后24周实验组的BALP、BGP稍有下降,但组内无显著性差异(P〉0.05),而TRAP-5b有明显下降(P〈0.05),这些指标与对照组比较差异显著(P〈0.05或P〈0.01);生物力学检测显示,实验组的假体拔出实验较对照组提高了约50%,扭转实验提高近1倍,且两组比较差异显著(P〈0.01);骨组织形态计量学显示,实验组中反映骨吸收的Oc.No/Tb.Pm、ES/BS明显减少;反映骨量和微结构的%Tb.Ar、Tb.N明显增多,而Tb.Sp明显变窄:反映骨形成与骨矿化的OS/BS、MAR、BFR/TV及%L.Pm也均明显增多;这些指标与对照组比较差异显著(P〈0.01或P〈0.05)。[结论]鲑鱼降钙素能明显减少人工假体周围骨量的丢失和抑制骨溶解;并加快假体周围的骨形成,提高骨密度,促进生理性骨矿化;还能改善骨质量,促进骨微结构改变,提高骨的生物力学特性并增加假体四周的支撑力。其对骨质疏松症兔的假体松动有明显的预防和治疗作用。这对临床预防和治疗人工关节的无菌性松动有很好的指导意义。  相似文献   
88.
丹参对持续癫痫幼鼠脑损伤保护作用的实验研究   总被引:2,自引:0,他引:2  
李伟  马华 《武警医学》2006,17(3):182-185,F0004
目的 探讨丹参对持续癫痫发作诱发幼鼠脑神经元损伤是否具有保护作用。方法 皮下及腹腔注射贝美格针诱发健康幼龄鼠癫痫持续状态发作。光镜下观察神经元病变情况;电镜观察海马神经元超微结构的改变。结果 持续癫痴组幼鼠脑组织光镜下可见明显的神经元病变。电镜下可见海马区神经元的超微结构病变。丹参治疗组神经元病变均轻于持续癫痴组;而正常对照组未见类似病变。结论 丹参在组织、细胞和亚细胞水平对持续癫病幼鼠脑神经元损伤具有一定的保护作用,为临床有效防治小儿惊厥性脑损伤提供了可靠的实验依据。  相似文献   
89.
18F-2beta-Carbomethoxy-3beta-(4-chlorophenyl)-8-(2-fluoroethyl)nortropane (18F-FECNT), a PET radioligand for the dopamine transporter (DAT), generates a radiometabolite that enters the rat brain. The aims of this study were to characterize this radiometabolite and to determine whether a similar phenomenon occurs in human and nonhuman primate brains by examining the stability of the apparent distribution volume in DAT-rich (striatum) and DAT-poor (cerebellum) regions of the brain. METHODS: Two rats were infused with 18F-FECNT and sacrificed at 60 min. Extracts of brain and plasma were analyzed by high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometric (LC-MS) techniques. Two human participants and 3 rhesus monkeys were injected with 18F-FECNT and scanned kinetically, with serial arterial blood analysis. RESULTS: At 60 min after the injection of rats, 18F-FECNT accumulated to levels about 7 times higher in the striatum than in the cortex and cerebellum. The radiometabolite was distributed at equal concentrations in all brain regions. The LC-MS techniques identified N-dealkylated FECNT as a major metabolite in the rat brain, and reverse-phase HPLC detected an equivalent amount of radiometabolite eluting with the void volume. The radiometabolite likely was 18F-fluoroacetaldehyde, the product expected from the N-dealkylation of 18F-FECNT, or its oxidation product, 18F-fluoroacetic acid. The distribution volume in the cerebellum increased up to 1.7-fold in humans between 60 and 300 min after injection and 2.0 +/- 0.1-fold (mean +/- SD; n = 3) in nonhuman primates between 60 and 240 min after injection. CONCLUSION: An 18F-fluoroalkyl metabolite of 18F-FECNT originating in the periphery confounded the measurements of DAT in the rat brain with a reference tissue model. Its uniform distribution across brain regions suggests that it has negligible affinity for DAT (i.e., it is an inactive radiometabolite). Consistent with the rodent data, the apparent distribution volume in the cerebellum of both humans and nonhuman primates showed a continual increase at late times after injection, a result that may be attributed to entry of the radiometabolite into the brain. Thus, reference tissue modeling of 18F-FECNT will be prone to more errors than analysis with a measured arterial input function.  相似文献   
90.
Complex regional pain syndrome (CRPS) was formerly known as “Sudeck’s atrophy”. The disease belongs to the group of neuropathic pain syndromes and is differentiated into three types. Type I is characterized by a lack of nerve lesions, type II by the presence of nerve lesions, and type III by the presence of other entities such as fibromyalgia. The exact pathogenic factors leading to the disease are still unknown and are currently the subject of investigation in various studies. These studies suggest a contribution of the central nervous system to the development and maintenance of CRPS. However, the clinical symptoms are well documented and include pain, autonomic changes and impaired motor function of the affected extremity. Diagnosis is based clinically on signs and symptoms. However, in a few cases radiography and scintiscanning may be useful to finalize the diagnosis. The treatment options are centred on the symptoms of pain, autonomic changes and functional impairment. A multidisciplinary treatment strategy is recommended, with surgeons, anaesthesiologists, physiotherapists and psychotherapists working together. Surgical intervention in this disease is only required in rare cases of neurological and bone pain, and the indications for such intervention are narrow and should be strictly observed.  相似文献   
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