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981.
982.
外周血细胞DNA、RNA及血红蛋白同时提取法 总被引:1,自引:0,他引:1
采用淋巴细胞分离液分离外周血中的有核细胞。经细胞裂解液处理,上清提取RNA,沉淀提取DNA,用分离液分离所得红细胞沉淀制备血红蛋白溶液,经对抽提物质量进行评价,发现3种提取物质量均高,本法能从少量外周血中同时分离DNA、RNA及血红蛋白,高效易操作,值得推广。 相似文献
983.
Objective To study the altered radiobiological effect of simulative intensity-modulated radiotherapy (SIMR) in cultured human nasopharyngeal carcinoma (NPC) cells and the related mechanism. Methods Single cell suspension of exponentially growing CNE-2 cells, a poor differentiated NPC cell line, was seeded and cultured for 12 hours, then the cells were irradiated in two different models by 6 MV X-ray beams at 3 Gy/min. In single fraction irradiation (SFR) model, cells were irradiated a single fraction of 0, 2, 4, 6 or 8 Gy within 0 to 3 minutes. In S1MR model, cells were irradiated 0, 2, 4, 6 or 8 Gy in 5 frac-tions with interval of 8.0-8.5 minutes between. Clonogenic assay was performed to determine the radiosen-sitivity. Cellular apoptosis was measured by flow cytometry. RT-PCR was used to detect mRNA expressions of Bax and Bcl-2, Respectively. Results Compared with SFR group, the survival fraction in SIMR group was higher at all the dose levels. The values of α, β, D0 and Dq were higher in SIMR group than in SFR group. At dose levels of 2 Gy, 4 Gy and 6 Gy, The early and late apoptotic cells in SIMR group were lower than in SFR group (21.20%: 15.89%, F=18.51, P=0.020;13.00%: 10.20, F=15.67, P=0.040).The mRNA expression of Bax was upregulated in a dose-dependent manner in the both groups. Compared with SFR group, the mRNA expression of Bax in SIMR group was lower at all the dose levels (Mean value of 76.75% : 62.50%, F =36.57, P =0.000). Bcl-2 mRNA expression at every dose level had no significant difference between the two groups (Mean value of 29.25% : 29.75%, F=0.74, P=0.800). Conclusions Prolonged delivery time in SIMR model can decrease the radiobiological effects. 相似文献
984.
985.
986.
This paper describes the results of the application of linear solvation energy relationships (LSERs) to quantitatively characterize the properties of adhesives and to evaluate the degree of drug-adhesive interaction in transdermal drug delivery formulations. Probe solutions were prepared in acetonitrile (ACN) for a set of probe compounds with different physicochemical properties, and were used to swell the adhesives for subsequent probe molecule-adhesive interactions. The degree of the interactions was measured by the 'sorbed' amount of probe molecules. Based on LSERs, the 'sorbed' amounts were linearly correlated with their properties. The corresponding coefficients reflect the differential interactions of these molecules with the adhesive and ACN, and are quantitative indications of the adhesive properties. Two different transdermal acrylate adhesives (isooctyl acrylate/acrylamide/vinyl acetate in the weight ratios of 75/5/20 and isooctyl acrylate/2-hydroxyethyl acrylate/vinyl acetate in the weight ratios of 58/20/18) were selected for the evaluation of the methodology. It is concluded that the first adhesive is more basic and hydrophobic, which is consistent with the use of acrylamide monomer and significant amount of isooctyl acrylate. The second adhesive is more acidic and polarizable due to a relatively high amount of the 2-hydroxyethyl acrylate. Additionally, the 'sorbed' amount can be regarded as an interaction parameter or index between a drug molecule and the adhesive. Finally, this parameter is expected to correlate with the thermodynamic properties of transdermal formulations such as drug solubility, diffusion coefficient, release rate, and maybe skin permeation rate. 相似文献
987.
目的:研究心肺复苏期间血管升压素与肾上腺素联合应用的复苏效果.方法:将符合入选标准的63例心脏停搏患者随机分为3组:大剂量肾上腺素组21例(A组),大剂量血管升压素组22例(B组),血管升压素+肾上腺素组20例(C组).分别观察3组自主循环恢复率、自主循环恢复时间、存活率.结果:A组、B组、C组自主循环恢复率分别为19.5%、36.4%、45.0%,C组高于A组、B组;C组存活率为30%,高于A组的4.8%、B组的13.6%;C组自主循环恢复时间短于A组、B组.结论:心肺复苏期间,联合应用血管升压素和肾上腺素比单独应用肾上腺素或血管升压素能显著提高自主循环恢复率和存活率,缩短自主循环恢复时间. 相似文献
988.
目的 观察低氧条件下血小板衍生性生长因子 (PDGF)对于培养人脐静脉内皮细胞 (HUVEC)增殖的影响。方法 流式细胞仪分析细胞周期各时相分布 ,氚 -亮氨酸 (3 H -Leu)掺入实验评价蛋白质合成 ,免疫组织化学方法检测增殖细胞核抗原 (PCNA)水平。结果 低氧可显著减少S期及G2 /M期细胞数 ,使停留于G0 /G1 期HUVEC细胞数增加 ,降低HUVEC3 H -Leu的掺入量及PCHA水平。低浓度的PDGF(5ng/ml)对低氧条件培养的HUVEC细胞周期时相分布、3 H -Leu的掺入量及PCNA水平影响不明显 ;高浓度PDGF(1 0ng、2 0ng)加速HUVEC由G1 期S期的转换 ,显著增加低氧培养HUVEC3 H -Leu掺入量 ,PCNA水平 ,此作用呈剂量依赖性。结论 PDGF能够拮抗低氧所致的培养HUVEC增生能力的下降 ,但低浓度PDGF(5ng/ml)作用不显著 ,剂量越大 ,拮抗作用愈显著。 相似文献
989.
高等医学院校医学化学教材改革的几点思考 总被引:2,自引:1,他引:1
医学的发展已进入分子水平,医学生必须具有扎实的化学基础才能适应专业学习及临床、科研工作的需要。现行医学化学教材大多沿用几十年前的模式,部分内容陈旧滞后,实用性不强。面对现实,改革势在必行。我们认为,突出重点、注重实用、体现医学特色应作为改革的方向。 相似文献
990.
持续压力超负荷对兔左心室细胞凋亡的影响 总被引:3,自引:1,他引:2
OBJECTIVE: To study the effect of chronic pressure overload on the apoptosis of the left ventricle myocytes in rabbits. METHODS: Rabbit models of chronic pressure overload-induced heart failure were prepared in which dynamic changes of apoptotic myocytes in the left ventricle were observed by way of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. RESULTS: Only a few apoptotic cells was observed in the sham-operated group, while in the experimental group, the apoptotic left ventricle myocytes significantly increased after operation, presenting a peak level between day 3 and day 7. Seven days after the operation, the apoptotic myocytes began to decrease and till day 14, the apoptotic cell number had been smaller than that measured on day 1. When signs of heart failure set in, the apoptotic myocytes were again increased (P<0.001). CONCLUSION: During chronic pressure overload, myocyte apoptosis in the left ventricle is elevated at the early stages and undulates subsequently, with the peak occurring before hypertrophy is obvious. 相似文献