NGF促再生神经功能恢复的实验研究

目的　运用电生理、类霍乱毒 -辣根过氧化物酶 (CB-HRP)逆行追踪的方法 ,研究神经生长因子 (nerve growth factorNGF)对再生神经功能恢复的影响。方法　 Wistar大白鼠 2 0只 ,切断两侧位于股骨中段的坐骨神经 ,硅胶管桥接形成神经再生小室 ,断端相距 6 mm。右侧再生小室内注入 NGF,左侧注入等量的生理盐水 ,分笼饲养 3个月。结果　NGF侧电生理数值 :L AT:(2 .0 8±0 .42 ) ms,CV:(35 .9± 8.6 7) m/s,AMP:(6 .18± 2 .90 ) mv± 0 .48) mv,各项指标两组数值标本均数的 t检验 P<0 .0 1。CB-HRP逆行追踪 ,被 CB-HRP标记的运动细胞数 NFG侧 :(4.2± 0 .974) ,NS侧 :(2 .3± 0 .483) ,两组数值样本均数的 t检验 P<0 .0 1。结论　通过电生理及 CB-HRP逆行追踪证实 ,NGF有促进再生神经功能恢复的作用     

聚氯乙烯膜盐酸奎宁选择电极的研制与应用

目的及方法 :本文首次使用鞣酸与六价铬形成的络合物为沉淀剂 ,使其与奎宁形成的分子缔合物为电活性物 ,制备了一种新型的 PVC膜盐酸奎宁选择电极。结果 :电极的 Nernst响应范围为 1.0× 10 - 1～ 1.0× 10 - 5 mol/ L;斜率为 5 3m V/ p C;检测限为 7.0× 10 - 6 mol/ L。结论 :此电极响应迅速 ,重现性好 ,用此电极以标准曲线法对药物中的盐酸奎宁进行了测定 ,操作简便 ,结果与药典法相符     

合欢皮对小鼠免疫功能的调节作用

目的 探讨合欢皮对小鼠免疫功能的影响。方法 用相当于生药１０ｍｇ／（ｋｇ．ｄ）、１００ｍｇ／（ｋｇ．ｄ）和５００ｍｇ／（ｋｇ．ｄ）合 皮水提取液,连续小鼠灌胃６ｄ,检测小鼠腹腔巨噬细胞对鸡红细胞（ＣＲＢＣ）的吞噬率和吞噬指数,刀豆素Ａ（ＣｏｎＡ）刺激小鼠腹腔巨噬细胞肿瘤坏死因子（ＴＮＦ）和脾淋巴细胞白细胞介素－２（ＩＬ－２）诱生的水平。结果 １００ｍｇ／（ｋｇ．ｄ）合欢皮使小鼠腹腔巨噬细胞的吞噬率     

Characterization and phylogenetic analysis of a neurovirulent Zika virus isolated from Cambodia in 2019

The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015–2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1^−/−) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD₅₀). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries.     

The acceptance of SARS-CoV-2 rapid antigen self-testing: A cross-sectional study in China

Compared with the nucleic acid amplification test (NATT), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen self-testing (RAST) has advantages in speed and convenience. However, little is known about people's acceptance and influencing factors for SARS-CoV-2 RAST. A cross-sectional study was conducted from April 21 to 30, 2022 in China. The χ² test and multivariate logistic regressions were used to identify the influencing factors. The structural equation model was used to test the extended protective motivation theory (PMT) model hypotheses. Among the total of 5107 participants, 62.5% were willing to accept the SARS-CoV-2 RAST. There were significant differences in acceptance among different residences (p < 0.001), educational level (p < 0.001), occupation (p < 0.001), monthly income (p < 0.001), travel frequency (p < 0.05), and feelings about NATT (p < 0.001). Response efficacy (β = 0.05; p = 0.025) and self-efficacy (β = 0.84; p < 0.001) had a positive effect, while response cost showed a negative effect (β = −0.07; p < 0.001). The public's major concerns about SARS-CoV-2 RAST are its reliability, testing method, price, and authority. Overall, a moderate intention to use SARS-CoV-2 RAST was found among the Chinese population. The extended PMT can be used for the prediction of intention to accept the RAST. We need to take measures to increase people's acceptance of SARS-CoV-2 RAST.     

Study on genetic polymorphisms of DCC gene VNTR in esophageal cancer

The abeted in Colo~ cancer gene (DCC) is re~ as a susceptibility gene in colol'eCtal cancer, whichis located on chlomesome 18qZI. 2. Ihactivation of thisgene may Play an i~ role dndng some Pimessessuch as ~ p~ssion and metastasis. With its ~allycloned, in lop, casinger et alllJ found that a vocablenumber tandem repeat (VNTR) is located wick an intwOf the DCC gene, its lepeat act is 2 hp,the core seqUence of (TA)n ~ numbers ~ 10 -- to tinies, whichis an ideal genetic rnalker. Esophageal…     

99mTc—DTPA—甲硝唑正常动物体内分布研究

目的：探讨＾９９ｍＴｃ－ＤＴＰＡ－甲硝唑在正常动物的体内分布。方法：经小鼠和家兔耳缘静脉注射＾９９ｍＴｃ－ＤＰＴＡ－甲硝唑（３．７ＭＢｑ）后５ｍｉｎ２４ｈ,连续采集血液和其它脏器标本,测其放射性。结果：＾９９ｍＴｃ－ＤＴＰＡ－甲硝唑正常小鼠生物分布除肝脏、肾脏外,其余器官无明显分布。家兔血液清除研究在血中清除快,在血中呈双指数下降Ｔ１／２α为０．４５ｈ,Ｔ１／２β为３．１８ｈ。结论：＾９９ｍＴｃ－     

PEG6000沉淀结合差速离心方法浓缩水中脊髓灰质炎病毒

建立一种简便,有效的从细菌培养物中纯化ＰＶ１病毒的方法用于水病毒消毒实验。方法ＰＶ１Ｈｅｎａｎ株在Ｈｅｐ－２细胞中增殖后用聚乙二醇６０００沉淀结合差速离心的方法纯化病毒,ＲＴ－ＰＣＲ和透射电镜鉴定提纯病毒的形态学和分子生物学特性。结论ＰＥＧ６０００结合差速离心的方法较之蔗糖密度梯度区带离方法易于操作且比单独ＰＥＧ沉淀有更高的纯化系数,是一种简便,有效的方法。     

聚乳酸酮洛芬微球的制备及其体外释放度

制备了生物可降解的材料聚乳酸,用粘度法测定其分子量,并选用Ａ、Ｂ、Ｃ三种不同分子量的聚乳酸为药物的载体,制备了酮洛芬微球（ＡＳ,ＢＳ,ＣＳ）,测定其粒径和体外溶出速率。结果表明催化剂四苯基锡用量增加,所得的聚乳酸分子量增加,而制备酮洛芬微球的聚乳酸分子量越大,其微球粒径越大,溶出速率越小。     

从20世纪诺贝尔医学奖看21世纪我国高等医学教育

20世纪诺贝尔医学奖中奖项目 98项中可看出基础医学中奖项目多于临床 ,为 80∶2 0 ;美国人中奖最多 ,英、德领先 ;中奖科学家出身名校并受名师潜移默化 ;医学发展极快 ,2 0世纪下半叶中奖项目难度大、知识面广 ,跨学科、多人合作、智慧科技含量高。为此我国在 2 1世纪的医学教育必须加大投入、重建师资队伍、教学内容及方法不断更新、重视基础医学及人文社会科学、培养学生求异创新思维、更新科技研究水平 ,加大国际交流并结合我国医学优势及需要必定能获得 2 1世纪诺贝尔奖