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51.
目的 初步探讨高迁移率族蛋白B1(HMGB1)致炎效应的信号转导机制。方法 清洁级雄性Wistar大鼠,取其腹腔巨噬细胞,培养3d后以10mg/L HMGB1刺激。刺激完毕后直接在培养瓶中裂解细胞,分别采用免疫沉淀、免疫印迹法和凝胶阻滞分析等技术观察不同时间点Janus激酶2(JAK2)、信号转导及转录激活子—1(STAT1)以及STAT3的活化情况。结果 HMGB1可诱导大鼠腹腔巨噬细胞STAT1、STAT3在短时间内(2h)活化,其中STAT3活化最为迅速,10min即可达到活化高峰。但HMGB1不能在短时间内(2h)诱导JAK2活化。结论 JAK/STAT途径可能参与了HMGB1致炎效应的信号转导机制。  相似文献   
52.
目的:测量国人全膝关节假体置换术胫骨近端截骨面后缘至腘窝血管之间的距离,以期为临床全膝关节置换术中避免损伤腘窝血管提供参考数据。方法:选择2006-06/12于解放军第二军医大学长征医院体检的50名正常成人(53膝),男29名(31膝),女21名(22膝)。所有观察对象均知情同意,且得到医院伦理道德委员会批准。对所有膝关节进行MRI扫描,在胫骨外侧平台以下10mm水平横断面上辨认腘动静脉,并测量胫骨近端截骨面后缘至腘窝动静脉的距离。结果:53膝全部进入结果分析,无脱落。①男性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.7±2.5,7.3±2.3)mm,95%可信区间分别为5.8~7.6mm,6.5~8.1mm。②女性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.6±1.9,7.1±2.7)mm,95%可信区间分别为:5.8~7.4mm,5.9~8.3mm。③不同性别观察对象胫骨近端截骨面后缘至腘血管的距离差异无显著性意义(P>0.05)。结论:腘窝血管紧邻全膝关节假体置换术胫骨近端截骨面后缘,不同性别间无明显差异。全膝关节假体置换术中进行胫骨近端截骨,特别是后方操作时需特别谨慎,以避免损伤腘窝血管。  相似文献   
53.
In this work we treat fMRI data analysis as a spatiotemporal system identification problem and address issues of model formulation, estimation, and model comparison. We present a new model that includes a physiologically based hemodynamic response and an empirically derived low-frequency noise model. We introduce an estimation method employing spatial regularization that improves the precision of spatially varying noise estimates. We call the algorithm locally regularized spatiotemporal (LRST) modeling. We develop a new model selection criterion and compare our model to the SPM-GLM method. Our findings suggest that our method offers a better approach to identifying appropriate statistical models for fMRI studies.  相似文献   
54.
Anophthalmia (no eye), microphthalmia (small eye) and associated ocular developmental anomalies cause significant visual handicap. In most cases the underlying genetic cause is unknown, but mutations in some genes, such as SOX2, cause ocular developmental defects, particularly anophthalmia, in a subset of patients. Here, we describe a four-generation family with a p.Asp123Gly mutation in the highly conserved partner-factor interaction region of the SOX2 protein, which is important for cell-specific actions of SOX2. The proband in this family has bilateral anophthalmia and several other family members have milder ocular phenotypes, including typical optic fissure coloboma. Expression studies indicate that Sox2 is expressed in the eye at the site of closure of the optic fissure during development. The SOX2 mutation in this family implicates the partner-factor interaction region of SOX2 in contributing to the specificity of SOX2 action in optic fissure closure. Our findings indicate that investigation of SOX2 in a broad range of eye anomaly patients aids in the determination of particular functions of SOX2 in development.  相似文献   
55.
Prospective, double-blind, randomized trials comparing atypical antipsychotic drugs (APDs) to typical APDs, such as haloperidol, indicate that atypical APDs provide a modest benefit to cognitive function in schizophrenia. However, the validity of this inference has been contested by suggestions that the cognitive improvements observed with atypical APDs reflect practice effects associated with repeated testing on the same neuropsychological instruments, or an avoidance of a deleterious effect of haloperidol on cognitive function that might be dose related. These alternate hypotheses were assessed by meta-analyses that 1) examined the relationship between cognitive change and dose of haloperidol within the control arms of prospective atypical vs. typical APD clinical trials; and 2) compared the magnitude of change observed within the haloperidol arms of these studies to estimated practice effects for several commonly used neuropsychological measures. The results indicate that overall cognitive performance improves while on haloperidol. Studies that used a low dose of haloperidol (<10 mg) did not yield larger effect sizes for overall cognitive function or specific neuropsychological measures than studies that used a high dose (>10 mg), although doses greater than 24 mg appear to have deleterious effects. For two of the six neuropsychological tests examined (digit symbol substitution and verbal fluency) the magnitude of change observed was significantly less than practice effects. The results indicate that although haloperidol may cause deleterious effects at very high doses, or in specific cognitive domains, these effects are not likely to explain the broader range of cognitive improvements observed with atypical APDs.  相似文献   
56.

Background  

In India, presently malaria shows a declining trend whereas Plasmodium falciparum (Pf) cases show an up trend. In central India, specifically, Madhya Pradesh (M.P.) a forested and tribal area, control of malaria is logistically difficult and outbreaks are frequently recorded, reasons for this being inadequate surveillance, poor reporting, a time lag in reporting to decision makers and a lack of geo referenced information to pin point the trouble spots for a timely preventive action.  相似文献   
57.
Aim: Although obesity and weight gain generally are anticipated to be caused by an imbalance between energy intake and energy expenditure, the significance of thyroid hormones (TH) remains unclear. Examination of mitochondrial function may reflect intracellular thyroid hormone effect and elucidate whether a lower metabolic rate is present. Methods: In a group of 34 obese adolescents (age <16 years and body mass index above the age‐related 95th percentile), and an age‐ and gender‐matched group of 32 lean adolescent, thyroid stimulating hormone (TSH) and basal oxygen consumption were measured and mitochondrial function in peripheral blood monocytes was determined by flow cytometry. Results: Significant increase in TSH (3.06 ± 1.56 mU/L vs. 2.33 ± 0.91 mU/L, p < 0.05) and a decrease in VO2 (129 ± 16 mL O2/m2*min vs. 146 ± 15 mL O2/m2*min, p < 0.05) were observed in obese adolescents compared with lean adolescents. Flow cytometry analysis demonstrated a lower mitochondrial mass (6385 ± 1962 a.u. vs. 7608 ± 2328 a.u., p < 0.05) and mitochondrial membrane potential (11426 ± 3861 a.u. vs. 14017 ± 5536 a.u., p < 0.05) in obese adolescents compared with lean adolescents. These results are even more pronounced in adolescents with obese mothers. Conclusion: In obese adolescents, the increased TSH and lowered VO2 propose a lowered basal metabolic rate and the impaired mitochondrial function suggests a decreased thyroid hormone stimulation of mitochondrial energy production. The maternal in‐heritage is suggestive of a basal metabolic defect or mitochondrial resistance for TH.  相似文献   
58.
如何提高脓毒症闰人营养支持的效果是当前的热点和难点之一。本实验前瞻性地对比观察了不同蛋白质供应负荷0.25g/V(kg.d)vs0.35gN/(kg.d),在脓毒症病人全有肠外营养支持中对蛋白质代谢状况的影响。结果发现,与低氮量TPN相比,高氮量TPN支持可改善血浆蛋白水平,增加累积氮平衡,但尿中3-MH排出量也有相应增加。  相似文献   
59.
Mammography with synchrotron radiation   总被引:2,自引:0,他引:2  
  相似文献   
60.
Background: Haemophilus aphrophilus is a rare cause of ocular infection. It has been reported once as a cause of late-onset endophthalmitis in a patient with an inadvertent bleb after cataract surgery. We present a case of Haemophilus aphrophilus bleb infection after a mitomycin trabeculectomy.
Methods: A 56-year-old woman presented with a bleb infection 10 weeks after a mitomycin C augmented trabeculectomy at a University tertiary referral practice of one of the authors (GET). The causative organism was Haemophilus aphrophilus , identified by the Toronto Public Health Laboratory, Ontario, Canada.
Results: The bleb infection resolved following topical, subconjunctival and intravenous antibiotic therapy. A formal bleb revision was required to repair a persistent bleb leak.
Conclusion: Patients who have had trabeculectomies augmented with mitomycin C may be predisposed to bleb infection with unusual organisms. Prompt diagnosis and treatment is necessary to control the infection. Increased awareness and communication with laboratory personnel may increase the isolation of this fastidious organism.  相似文献   
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