长三角地区特色小镇空间分布及其影响因素

选取长三角地区376个特色小镇为研究对象,综合运用最邻近指数、核密度指数、缓冲区分析等GIS空间分析方法和地理集中指数、不均衡指数、地理联系率等数理分析方法探究其空间分布特征及影响因素,结果如下:(1)长三角地区特色小镇基于其主导产业可分为高端制造、信息经济、金融、创意时尚、传统产业、健康、历史经典、旅游8大类型,旅游类是该地区最主要的小镇类型;(2)长三角地区特色小镇空间分布不均衡,分布类型为集聚分布型;(3)长三角地区特色小镇分布密度核心区位于杭州市东北部,2个次级核心区分别是苏州市和嘉兴市,各类特色小镇分布密度核心存在分异;(4)自然因素包括地形条件、水文条件,人文因素包含经济与人口、创新能力、交通条件,二者共同影响长三角地区特色小镇空间分布。

Effects of Exogenous Amino Acids on the Contents of Amino Acids in Tobacco Leaves

The effect of three amino acids on the growth of flue-cured tobacco was studied with water culture. The results showed that the three amino acids improved the growth of flue-cured tobacco and increased the contents of chlorophyll a, chlorophyll b and carotenoid in tobacco. At the same time, the activities of NR (nitrate reductase), INV(invertase) and root growth activity were also significantly enhanced. The exogenous glutamic, aspartate and phenylalanine all increased the amino acid contents of tobacco leaves. Of these three amino acids, glutamic had the greatest effect, the next was aspartate, and phenylalanine had the least effect. These three amino acids all had significantly increased the accumulation of amino acids in the leaves of individual plants of tobacco; and the magnitude of accumulation indicated aspartate > glutamic > phenylalanine.

全脊柱内镜椎板开窗减压术治疗颈椎管狭窄症

目的 评估全脊柱内镜椎板开窗减压术治疗颈椎管狭窄症的可行性及临床疗效,总结手术操作技巧。方法 纳入自2018-09-2020-04诊治的47例颈椎管狭窄症,在颈椎有限元生物力学研究基础上采用全脊柱内镜椎板开窗减压术治疗,比较手术前后疼痛VAS评分、NDI指数、JOA评分,记录相关并发症并了解其改善情况。结果 47例术中均实现颈髓完全减压,术后未出现颈椎轴性疼痛。本组手术时间为(101.70±9.34)min,术中出血量为(5.43±1.41)mL。47例均获得随访,随访时间平均19.7(12~36)个月。术后2例出现神经麻痹症状,随访3个月后症状消失。2例出现脑脊液漏,术后2周闭合。末次随访时影像学检查结果显示椎间隙高度未明显降低,部分患者颈椎前凸角度有少许改善。1例术后2年C_(4、5)节段椎间盘再次突出,考虑与患者颈部过伸性损伤有关,再次全内镜减压取出突出的髓核组织。术后3 d疼痛VAS评分、NDI指数、JOA评分较术前明显改善,且术后3个月、12个月持续改善,差异有统计学意义(P<0.05)。结论全脊柱内镜椎板开窗减压术治疗颈椎管狭窄症操作精准、安全,减压效果好,早中期疗效满意,可有效改善患者临床症状及功能状态,值得临床进一步推广应用。