Vero细胞和脊髓灰质炎病毒在无血清条件下的培养探究

目的：探索Vero细胞和脊髓灰质炎病毒在无血清条件下的最佳培养条件,为无血清培养Vero细胞生产脊髓灰质炎疫苗奠定基础。方法选择直接适应（直降组）和序贯适应（驯化组）两种无血清培养方法,观察Vero细胞和脊髓灰质炎病毒在无血清条件下的生长情况,并检测脊髓灰质炎病毒及其病毒滴度。结果 Vero细胞在两种无血清条件下均生长良好,其中驯化组细胞生长速度更接近对照组。以脊髓灰质炎病毒Sabin株Ⅰ型分别感染直降组、驯化组和对照组细胞的病毒滴度平均值分别为8．94、8．81和8．94 LgCCID50/mL;Ⅱ型病毒滴度平均值分别为8．84、8．25和7．94 LgCCID50/mL;Ⅲ型病毒滴度平均值分别为8．91、8．57和8．63 LgCCID50/mL;且3组的变异系数（ CV）均小于10％。结论 Vero细胞在无血清条件下生长良好,无血清培养的Vero 细胞可用作脊髓灰质炎疫苗生产的基质。     

SPF和正常鼠下呼吸道菌群多样性研究

目的 探讨SPF和正常鼠下呼吸道菌群多样性区别,为研究洁净环境下呼吸道菌群对免疫耐受形成的影响提供简便的动物模型.方法 采用飞行质谱和DGGE的方法检测正常和SPF BALB/c小鼠及Wistar大鼠呼吸道支气管肺泡灌洗液中菌群多样性的区别.结果 SPF BALB/c小鼠下呼吸道菌群丰度小于普通小鼠,下呼吸道菌群丰度小于消化道.SPF Wistar大鼠下呼吸道菌群丰度小于普通大鼠.结论 SPF环境造成鼠下呼吸道菌群丰度减小.     

珠子参地上部分氨基酸测定及营养评价

对珠子参茎、叶、花的氨基酸组成与含量进行测定和营养评价分析。结果表明,珠子参茎、叶、花中均含有17种常见氨基酸,氨基酸总量分别为3.73%,14.80%和8.72%;珠子参的茎中必需氨基酸与总氨基酸的比值(E/T)为0.39,必需氨基酸与非必需氨基酸的比值(E/N)为0.64,叶中E/T为0.41,E/N为0.71,花中E/T为0.39,E/N为0.63,氨基酸配比较为合理;珠子参茎、叶、花中蛋氨酸+胱氨酸均为第一限制氨基酸;珠子参茎、叶、花中均含有γ-氨基丁酸,含量分别为0.12%,0.26%和0.16%,叶片中γ-氨基丁酸的含量最高。     

焦磷酸测序检测食品中鼠伤寒沙门氏菌

根据鼠伤寒沙门氏菌的特异序列,分别设计扩增引物和测序引物,建立焦磷酸测序检测鼠伤寒沙门氏菌的方法。针对鼠伤寒沙门氏菌设计特异性扩增引物,对目标片段进行PCR扩增,然后制备单链模板,并利用测序引物进行焦磷酸测序。测序结果表明,6株不同来源的鼠伤寒沙门氏菌均可以扩增出碱基序列为TACAACCGGA GTGCACATTA ATCCCGCAGC的基因片段,而30株阴性对照菌株均未得到扩增。进行BLAST比对表明,该序列与GenBank中鼠伤寒沙门氏菌的碱基序列100%匹配。焦磷酸测序法是一种快速、准确的检测方法,可用于食品中鼠伤寒沙门氏菌的快速检测。     

参松养心胶囊对缺血性心力衰竭患者心率变异性的影响

目的：评价参松养心胶囊对缺血性心力衰竭患者心率变异性的影响。方法：选择缺血性心肌病心衰患者40例,在常规抗心衰治疗（利尿剂、血管紧张素转换酶抑制剂／血管紧张素受体抑制剂、B受体组滞剂、醛固酮拮抗剂及洋地黄制剂）基础上加服参松养心胶囊1．2g,每日3次,连用8周。以超声心动图和24小时动态心电图分别观察治疗前、治疗后8周患者的心脏功能和心率变异性的变化情况。结果：参松养心胶囊治疗8周后,患者左室射血分数较治疗前显著增加（33．5±5．2％vs42．6±5．7％,P〈0．001）,正常R-R间期标准差（SDNN）和连续5分钟正常R-R间期均值的标准差（SDANN）均显著增加（P〈0．05）,分别为（97．4±40．6vs110．6±29-3msecs）和（80．5±29．4vs98．4±30．6msecs）。结论：常规抗心衰治疗基础上给予参松养心胶囊治疗能够有效改善缺血性心肌病心衰患者心率变异性和心脏功能。     

Atomic Force Microscopy Analysis of Progenitor Corneal Epithelial Cells Fractionated by a Rapid Centrifugation Isolation Technique

Purpose

To investigate the use of atomic force microscopy (AFM) to image the three groups of corneal epithelial cells fractionated by a novel rapid centrifugation isolation technique.

Methods

Epithelial cells harvested from primary cultures of rabbit limbal rings were centrifuged onto uncoated dishes, first at 1400 rpm and then at 1800 rpm. The adherent cells after centrifugation at 1400 rpm (ATC1), the adherent cells at 1800 rpm (ATC2) and the non-adherent cells at 1800 rpm (NAC) were investigated for BrdU retention and were subjected to contact mode AFM and Transmission Electron Microscopy (TEM).

Results

Compared with unfractionated cells, the ATC1 group, accounting for about 10% of the whole population, was enriched in BrdU label-retaining cells. There were dramatic overall shape, surface membrane and intra-cellular ultrastructure differences noted among ATC1, ATC2 and NAC populations. The whole cell roughness measurements were 21.1±1.5 nm, 79.5±3.4 nm and 103±4.6 nm for the ATC1, ATC2 and NAC groups, respectively. The mero-nucleus roughness measurements were 34.2±1.7 nm, 13.0±0.8 nm and 8.5±0.5 nm in the ATC1, ATC2 and NAC populations, respectively.

Conclusions

AFM was found to be a good tool for distinguishing among the three groups of cells. BrdU label retention, the AFM parameters and TEM together suggest that the ATC1, ATC2 and NAC populations may be progenitor corneal epithelial cells, transit amplifying cells and terminal differentiation cells, respectively.     

室内外评价在黄淮海夏玉米区释放玉米螟赤眼蜂防治亚洲玉米螟的可行性

为了评价在黄淮海夏玉米区释放米蛾卵繁育的玉米螟赤眼蜂Trichogramma ostriniae防治亚洲玉米螟Ostrinia furnacalis的可行性,本试验在室内组建了玉米螟赤眼蜂在亚洲玉米螟卵上的实验种群生命表的基础上,在河南省鹤壁市滑县测定了玉米螟赤眼蜂对亚洲玉米螟的防治效果,筛选出了具有较好防治效果的释放密度和释放方法。结果显示,米蛾卵繁育的玉米螟赤眼蜂在亚洲玉米螟卵上的净生殖力R0为9.8240,单雌平均产雌率R0'为12.6256,2013年在河南省鹤壁市滑县释放玉米螟赤眼蜂能使亚洲玉米螟虫口密度减退73.91%,释放密度为2.25×105头/hm2。2014年在鹤壁市淇滨区钜桥镇采用传统的人工挂卡和新型的无人机释放玉米螟赤眼蜂,亚洲玉米螟虫口密度减退54.55%-68.16%。结果表明,在黄淮海夏玉米区释放米蛾卵繁育的玉米螟赤眼蜂防治玉米螟是可行的。     

教育中的同伴效应研究述评：概念、模型与方法

教育中的同伴效应是指宿舍、班级、年级或学校内同伴的背景、行为及产出对学生产出或行为的影响。教育中的同伴效应起初使用的是同质性模型,即认为无论个体如何选择同伴,总效益是不变的,同伴效应是一种零和现象。进而发展到异质性模型,即认为同伴效应对不同个体的作用结果是不一样的,通过合理的分配能够提高总效益。研究方法则从以普通最小二乘法为主的统计关联研究,发展到借助于随机实验、自然实验以及准实验的因果推断研究。同伴效应的研究为正确地认识和评价相关教育政策,获得最优组织学校教学的方式,提高教学效率提供了依据。     

Low‐Temperature Solution‐Based Phosphorization Reaction Route to Sn4P3/Reduced Graphene Oxide Nanohybrids as Anodes for Sodium Ion Batteries

Different from previously reported mechanical alloying route to synthesize Sn _x P₃, novel Sn₄P₃/reduced graphene oxide (RGO) hybrids are synthesized for the first time through an in situ low‐temperature solution‐based phosphorization reaction route from Sn/RGO. Sn₄P₃ nanoparticles combining with advantages of high conductivity of Sn and high capacity of P are homogenously loaded on the RGO nanosheets, interconnecting to form 3D mesoporous architecture nanostructures. The Sn₄P₃/RGO hybrid architecture materials exhibit significantly improved electrochemical performance of high reversible capacity, high‐rate capability, and excellent cycling performance as sodium ion batteries (SIBs) anode materials, showing an excellent reversible capacity of 656 mA h g^?1 at a current density of 100 mA g^?1 over 100 cycles, demonstrating a greatly enhanced rate capability of a reversible capacity of 391 mA h g^?1 even at a high current density of 2.0 A g^?1. Moreover, Sn₄P₃/RGO SIBs anodes exhibit a superior long cycling life, delivering a high capacity of 362 mA h g^?1 after 1500 cycles at a high current density of 1.0 A g^?1. The outstanding cycling performance and rate capability of these porous hierarchical Sn₄P₃/RGO hybrid anodes can be attributed to the advantage of porous structure, and the synergistic effect between Sn₄P₃ nanoparticles and RGO nanosheets.