正常人收缩期左侧房室平面位移的超声心动图检测

目的：利用超声心动图检测正常人左侧房室平面位移幅度。方法：被检对象为１４４ 例正常人,男７２ 例,女７２ 例。按不同年龄分为６ 组,分别为：Ⅰ组（ｎ＝ ２４ ,３～６ 岁）;Ⅱ组（ｎ＝２４ ,７～１４ 岁） ;Ⅲ组（ｎ＝２４,１５～１９ 岁） ;Ⅳ组（ｎ＝ ２４,２０～３９ 岁）;Ⅴ组（ｎ＝２４ ,４０ ～５９ 岁） 及Ⅵ组（ｎ＝ ２４ ,≥６０ 岁）。结果：①左心收缩期房室平面位移测值在Ⅰ组～Ⅴ组之间无显著性差异（ Ｐ＞０－０５）,而Ⅵ组测值较Ⅰ组～Ⅴ组的测值均低（ Ｐ＜ ０－０５）;②左心收缩期房室平面位移测值不受心率、血压、体表面积及性别的影响。结论：①左侧房室平面位移测值受年龄因素影响;②制定正常左侧房室平面位移测值可以不考虑心率、血压、体表面积及性别的影响     

雷公藤内酯醇抗人肝癌SMMC-7721细胞活性研究

目的: 评价雷公藤内酯醇抗人肝癌SMMC-7721细胞的作用.方法: 采用体外细胞培养和SD大鼠体内肿瘤接种两种衡量方法,体外细胞培养检测指标包括细胞形态观察,台盼蓝染色,DAPI染色,DNA ladder;SD大鼠体内接种肿瘤指标检测用游标卡尺测量肿瘤体积大小.结果: 与对照组相比,体外培养肿瘤细胞在用药后活细胞大幅减少,体内接种肿瘤细胞在用药后,肿瘤块体积较小且增长缓慢,而对照组肿瘤体积却大幅增长.结论: 雷公藤内酯醇对体外和体内培养的人肝癌SMMC-7721细胞有明显的生长抑制作用和促凋亡作用.     

胞苷脱氨酶基因对小鼠大剂量化疗的保护作用

Objective:To explore the feasibility of transfecting cytidine deaminase(CD)gene into mouse bone marrow cells in order to observe the drug resistance of high dose Ara-C and improve the tolerance of myelosuppression following combination chemotherapy.Methods:Human cytidine deaminase gene was transfected into mice bone marrow cells by retroviral vector.Resistant colony-forming unit granulocyte-macrophage(CFU-GM)assay was performed after the transfected mice bone marrow cells treated by the Ara-C.DNA was extracted from mice bone marrow cells.The drug resistant gene in mice bone marrow cells after transfection was detected by PCR.Results:Bone marrow cells of lhe donor mice cultured with lhe retroviral producer cells showed the drug resistant colonies and resistance to Ara-C,so did accept mice transplanted with the CD gene(CFU-GM of donor mice was 52%,X2=124.62,P＜0.01:accept mice was 54%,X2=126.26.P＜0.01,both compared with the contrast group).The animal survival rate was significantly higher in gene transfected group than that of the control(X2=7.42.P＜0.01).CD gene of transfected bone marrow cells was confirmed by PCR.Conclusion:CD gene can be transfected into bone marrow cells of mice efficiently and increase the drug resistance to Ara-C.     

BrdU替代的人外周血淋巴细胞染色体的DNase-1敏感区

用本室建立的染色体原位切口移位方法,详细描述了人淋巴细胞染色体上DNase-1敏感区的分布。与已知的G带、R带图谱和六对已发表的染色体D带图谱比较,表明所揭示的B带与G带、R带和D带有明显的差异,染色体原位切口移位后的DNase—1敏感区多分布在具有转录活性的常染色质区,而异染色质区则通常与失活的基因部位有关。作者对B带的生物学意义和应用价值进行了详细讨论。     

高压氧对孤独症大鼠行为及外周血IL-1β、IL-6和IL-10水平的影响

目的:观察高压氧对丙戊酸钠孤独症模型鼠行为及外周血细胞因子水平的影响,探讨高压氧治疗孤独症的可能机制。方法:选取雌性Wistar大鼠,于孕第12.5天时腹腔注射丙戊酸钠600 mg/kg,产下的子代雄鼠20只,随机分为高压氧组和模型组,每组10只;正常对照组为腹腔注射等体积生理盐水的雌鼠产下的子代雄鼠10只。评价各组大鼠的生长和发育情况、运动活性、社会行为及学习记忆能力,采用ELISA法测定各组大鼠外周血IL-1β、IL-6和IL-10水平。结果:孤独症模型鼠生长发育迟缓、重复刻板行为、社会活动减少,高压氧组大鼠以上指标较模型组有所改善;模型组大鼠外周血中IL-1β、IL-6、IL-10水平升高,而高压氧组以上指标均较模型组下降(P均<0.05)。结论:孤独症的发病可能与细胞因子的表达水平异常有关;高压氧可能通过降低细胞因子IL-1β、IL-6、IL-10的水平,从而改善孤独症大鼠的生长发育及社会行为。     

Synergistic effect of graphene and silicon dioxide hybrids through hydrogen bonding self-assembly in elastomer composites

A novel graphene–silicon dioxide hybrid (HGS) was prepared by plant polyphenol-tannic acid (TA) functionalized pristine graphene (G-TA) and primary amine-containing silane coupling agent modified SiO₂ (Si–NH₂). Through strong hydrogen-bonding interaction between the phenolic hydroxyl groups on G-TA and primary amine groups on Si–NH₂, SiO₂ was uniformly loaded to the surface of graphene. Due to the synergistic dispersion effect of graphene and SiO₂, which prevents restacking and re-aggregating of both graphene and SiO₂, HGS hybrids were distributed evenly in the natural rubber (NR) matrix (HGS@NR). Simultaneously, the surface roughness of graphene after loading SiO₂ and the interfacial interaction between the HGS hybrid and NR matrix were substantially improved. Due to the good dispersion and strong interface, the overall properties of HGS@NR nanocomposites are drastically enhanced compared with those of GS@NR nanocomposites prepared by dispersing the blend of unmodified graphene and SiO₂ (GS) in NR. The HGS@NR nanocomposites possess the highest tensile strength up to 27.8 MPa at 0.5 wt% and tear strength of 60.2 MPa at 0.5 wt%. Thermal conductivities of the HGS@NR nanocomposites were found to be 1.5-fold better than that of the GS@NR nanocomposites. Also, the HGS@NR nanocomposites exhibit excellent abrasive resistant capacity that is nearly 2-fold better than that of the GS@NR nanocomposites. These results suggest that HGS has great potential in high-performance nanocomposites and a new strategy of constructing the efficient graphene–SiO₂ hybrid fillers has been established.

A novel graphene–silicon dioxide hybrid (HGS) was prepared by plant polyphenol-tannic acid (TA) functionalized pristine graphene (G-TA) and primary amine-containing silane coupling agent modified SiO₂ (Si–NH₂).     

Effect of Solvothermal Reaction-Time on Microstructure and Microwave Absorption Properties of Cobalt Ferrite

Cobalt ferrite is synthesized via a simple solvothermal method. Then, the effect of the degree of cobalt-ferrite growth on its morphology, structure, electromagnetic performance, and microwave absorption is studied as a function of the solvothermal reaction time. When the reaction time during synthesis is 8 h, the structure of cobalt ferrite is hollow spheres. In addition, when the reaction time is 12 h and 16 h, it becomes a submicron sphere with a diameter of 100–150 nm. With the increase of reaction time, cobalt ferrite underwent the process of cobalt ferrite formation, hollow structure formation, hollow structure disappearance, agglomeration separation and reagglomeration in 4–16 h. In general, CoFe₂O₄-8h shows better microwave absorption-the effective absorption bandwidth is 9.84 GHz (6–15.84 GHz) for a thickness of 1.72–3.72 mm. This represents a minimum return loss of −47.24 dB. A better understanding of both the synthesis parameters and the relationship between structure and electromagnetic properties can open new possibilities for applications and the development of microwave absorbing materials.     

Mutation analysis of 13 RM Y-STR loci in Han population from Beijing of China

International Journal of Legal Medicine - Two five-color fluorescence multiplex amplification systems of 13 Y chromosome short tandem repeat (Y-STR) loci (DYF387S1, DYF399S1, DYF403S1a/b, DYF404S1,...     

应用自回归移动平均模型预测分析江西省流行性腮腺炎的发病趋势

目的 应用自回归移动平均模型（ARIMA）预测分析江西省流行性腮腺炎的发病趋势。方法 利用ARIMA对江西省2015-2019年每月流行性腮腺炎报告发病数进行建模,预测12个月的发病数,并与2020、2021、2022年报告发病数进行比较分析。结果 最优模型为ARIMA（0,2,1）（1,2,0）₁₂。预测发病数显著高于2020、2021、2022年报告发病数。2020、2021、2022年流行性腮腺炎报告发病数较预测发病数分别减少54.02%、63.40%、66.09%。结论 2020-2022年江西省流行性腮腺炎报告发病数明显低于预测发病数,考虑与非药物干预措施、免疫策略的改变等有关,建议进一步加强流行性腮腺炎监测,以更好应对流行性腮腺炎疫情。