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961.
Heterogeneous carbon-based materials with high porosity are attracting increased attention for energy storage due to their enhanced capacity and rate performance. Herein, we report a sulfur-doped porous carbon material, which is achieved by spray-drying and subsequent sulfuration. The porous structure can provide vast diffusive tunnels for the fast access of electrolytes and sodium ions. Also, the S–C bond increases the electrical conductivity of the carbon frameworks and offers excessive reaction sites for sodium-ion storage. The elaborated carbon architecture enables a high capacity of 370 mA h g−1 at 0.5 A g−1 and provides an excellent rate performance for long-term cycling (197 mA h g−1 at 2.0 A g−1 for 650 cycles). Considering the scalable and facile spray-pyrolysis preparation route, this material is expected to serve as a low-cost and environmentally friendly anode for practical sodium-ion batteries.A novel S-doped porous carbon material with superior sodium storage performance was obtained through spray-drying and subsequent sulfur doping treatment. 相似文献
962.
Bin Ni Xiang Guo Ning Xie Songkai Li Fengjing Zhou Feng Zhang Qi Liu 《European spine journal》2013,22(2):260-267
Purpose
To retrospectively evaluate the outcome of C1–2 transarticular screws combined with C1 laminar hooks fixation.Methods
All patients underwent atlantoaxial fixation during a 5-year period. The surgical technique and treatment procedures were intensively reviewed and clinical symptoms, neurological function and imaging appearance were retrospectively evaluated.Results
The clinical and radiology follow-up indicated a stable arthrodesis and clinical relief from symptoms for all patients. All patients with neurological defects improved an average of 1.33 grade at their most recent clinical assessment, P < 0.05; their average admission ASIA motor score, pin prick score and light touch score improved to an average follow-up ASIA score of 99.80 (99.83 ± 0.38), 111.83 (111.83 ± 0.45), and 111.89 (111.89 ± 0.32), respectively. No neurovascular impairment and case of implant failure were observed.Conclusions
The C1–2 transarticular screws combined with C1 laminar hooks fixation is a reliable technique for atlantoaxial instability. 相似文献963.
目的:探讨后腹腔镜离断式肾盂成形术中输尿管吻合及双J管置人方法的改良及应用效果。方法:2010年6月~2013年1月,对32例肾盂输尿管连接部梗阻(ureteropelvicjunctionobstruction,UPJO)患者实施后腹腔镜离断式肾盂成形术,吻合方法采取两针固定连续缝合法,双J管放置采取Trocar外推置法。观察手术时间、吻合时间、置双J管时间、住院时间、并发症发生率、引流管放置时间等,总结手术技巧,并与前期18例采用间断缝合和双J管经Trocar内放置的后腹腔镜离断式肾盂成形术进行比较。结果:两组手术均获成功。改良手术组和对照组平均手术时间分别为(78.2±16.3)min、(114.7±17.5)min(P〈0.05),输尿管吻合时间分别为(24.2±4.9)min、(49.4±7.5)min(P〈0.05),双J管置入时间分别为(3.6±1.0)min、(9.1±2.2)min(P〈0.05),两组引流管放置时间、住院时间和并发症发生率比较差异无统计学意义(P〉O.05)。改良手术组随访3~30个月,平均9.2个月,B超提示肾积水消失11例,肾积水不同程度减轻21例。结论:后腹腔镜离断式肾盂成形术中采取两针固定连续缝合法吻合,可以降低输尿管吻合难度,缩短手术时间;经Trocar外推置法放入双J管,简便快速。 相似文献
964.
HUANG Li FENG Bing PANG Qi CHEN Ji-gang GUO Yan-hong DU Xiang YUAN Fa-huan. 《中华肾脏病杂志》2013,29(3):189-194
Objective To observe the effects of endoplasmic reticulum stress (ERS) on the activation of monocytes induced by high glucose and explore the underlying mechanism. Methods The monocyte cell line THP-1 was stimulated with high glucose, and then treated with molecular chaperone betaine. The levels of glucose regulation protein 78 (GRP78) and p-JNK, which were associated with ERS were detected by real-time PCR and Western blotting. The proliferation of the cell line was detected by MTT method. Transwell and immunofluorescence were applied to observe the chemotaxis and phenotype of cells respectively. Results The levels of GRP78 and p-JNK of THP-1 cells stimulated by high glucose were significantly increased compared with the normal control group (all P<0.05). The proliferation and chemotactic were also enhanced (all P<0.05). The number of cells in M1 phenotype was increased remarkably (P<0.05). All the indexes above could be rescued by betaine. Conclusion The activation of THP-1 cells can be induced by high glucose through ERS, while molecular chaperone betaine can reverse the activation. 相似文献
965.
吻合掌侧静脉及保留指甲的指尖再植 总被引:1,自引:1,他引:0
目的: 探讨手指指尖离断的治疗方法及临床效果。方法: 2007年10 月至2011年6月治疗13例18指指尖离断患者,其中男9例,女4例;年龄17~45岁,平均26岁。伤后至就诊时间30 min~5 h,断指缺血时间1.5~7 h,均为常温保存。采用吻合掌指静脉及保留指甲的方法进行再植。结果: 13例18 指断指均成活并获随访,术后无血管危象发生。随访时间为3~24个月,平均14个月。患指外形及长度与健指相似,指甲平整,关节活动良好,触、痛觉恢复,两点辨别率3~6 mm,平均5 mm.根据中华医学会手外科学会断指再植功能评定标准评定,优14指,良3指,差1指。结论: 采用吻合掌侧静脉及保留指甲的方法进行指尖再植,不仅可以提高断指成活率还可以恢复良好的外观及功能,是一种理想的方法。 相似文献
966.
967.
目的:观察Q开关Nd:YAG 1064nm激光联合口服氨甲环酸片治疗黄褐斑的临床疗效。方法:2011年7月~2012年10月,选取门诊就诊的黄褐斑患者30例,随机分为治疗组和对照组,每组各15例。治疗组:接受Q开关Nd:YAG 1064nm激光联合口服氨甲环酸片治疗;对照组:仅接受Q开关Nd:YAG激光治疗。每次治疗后都辅以维C导入及胶原蛋白修复面膜外敷,每2周治疗1次,10次为1个疗程;治疗组同时口服氨甲环酸片,每日2次,每次250mg,连服半年。1个疗程结束即评判疗效,治疗期间及1个疗程结束后3个月观察疗效及不良反应。结果:治疗组总有效率为93.3%,对照组为73.4%,两组疗效比较,差异均有统计学意义(P<0.05),未见明显不良反应。结论:Q开关Nd:YAG 1064nm激光联合口服氨甲环酸片治疗黄褐斑优于单用Q开关Nd:YAG激光治疗,且不良反应少,适合临床应用。 相似文献
968.
目的:观察应用BEGO种植系统进行前牙区种植修复的临床效果。方法:应用BEGO种植系统对302例部分前牙缺失患者进行即刻或延期种植,共植入482枚种植体,采用金属烤瓷冠桥或氧化锆全瓷冠桥修复。通过临床检查及X线检查,评估种植体周骨高度丧失情况。结果:观察1~4.5年,3颗种植体于种植后6个月进行二期手术时发现未形成骨结合,松动取出;其余种植体均稳固无松动,完成冠桥修复,成功率达99.4%,患者对临床效果满意。结论:BEGO种植系统应用于前牙区其操作简单可靠,可以取得较理想的前牙区美学效果。 相似文献
969.
目的:设计并筛选人血管内皮生长因子(VEGF)有效RNA干扰片段,构建VEGF慢病毒表达载体。方法:对人VEGF基因编码区分析,筛选序列3条,阴性对照序列l条,通过连接线性化的plenti6.3-MIR载体,构建miRNA慢病毒载体质粒,并转化至感受态细胞DH5α,进行测序验证。在脂质体介导下转染293T细胞,包装生产慢病毒,测定其滴度。慢病毒载体转染人肝癌细胞MHCC97L,用Real-time PCR检测干扰效果。结果:测序证实3个VEGF基因RNAi慢病毒载体质粒构建成功。慢病毒载体经293T细胞包装成功,测定病毒的滴度分别为3.23×109、3.30×109、3.73×109TU/mL。3个慢病毒载体转染人肝癌细胞MHCC97L后,VEGF基因在mRNA水平受到抑制,其中miR-200序列效果最佳,对VEGF基因表达的干扰效率可达72%。结论:成功构建并筛选了人VEGF基因RNAi慢病毒载体及有效靶点,为进一步深入研究VEGF基因与抗肿瘤药物药效关系提供实验基础。 相似文献
970.
Xiang Zhao Chao Guo Gang-Sheng Zhao Tiao Lin Zhong-Li Shi Shi-Gui Yan 《The Journal of arthroplasty》2013
We objectively appraised available evidence regarding the threshold for the number of polymorphonuclear leukocytes required in frozen section tests used to diagnose periprosthetic infection. Pooled summary estimates for sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio (OR) were compared for ten and five polymorphonuclear leukocytes per high power field as the threshold. The total cohort included 1011 patients and the rate of infection was 19.2%. Although there was no difference in sensitivity or diagnostic OR, specificity was significantly higher for ten than for five polymorphonuclear leukocytes per high power field (p = 0.007) In sum, a threshold of 10 polymorphonuclear leukocytes is better for diagnosing periprosthetic infections. 相似文献