去甲二氢愈创木酸的全合成

以香草醛为原料,经甲醚化,氧化和Claisen缩合,合成了相应的β 酮酸酯,再经改进的Knor反应,实现β-酮酸酯的偶联,通过环化、选择性氢化还原等反应,成功地合成了去甲二氢愈创木酸(nordihydroguaiaretic acid);呋喃愈创木酚二甲醚(furoguaiacin dimethyl ether)和二氢愈创木酸二甲醚(dihydroguaiaretic acid dimethyl ether)。     

HPV-16 E7 protein bypasses keratinocyte growth inhibition by serum and calcium

The E6 and E7 genes of HPV-16 or HPV-18 both are necessary for effective immortalization of primary human genital keratinocytes. To analyse the individual role of E6 and E7 genes in dysregulating cell growth, we cloned the HPV-16 E6, E7 and E6/E7 genes into retroviruses. Primary human keratinocytes (PHK) were then infected with these retroviruses and selected in differentiation-inducing medium (high calcium and serum). The E6/E7 retroviruses were the most effective at inducing differentiation-resistant colonies. Intermediate numbers of colonies were induced by E6 and low numbers by E7. Interestingly, only cultures infected with E7 and E6/E7 retroviruses showed a significant proportion of cells progressing into the S phase, consistent with our earlier studies showing that E7 is required for the efficient immortalization of genital keratinocytes. Accompanying this entry into S phase, the E7 or E6/E7 transduced cells expressed high levels of cyclins A, B and E, but lower levels of cyclin D. In addition, cdc-2, cdk-2 and cdk-4 were also increased. No significant differences were detected in the expression of c-myc and c-fos between the vector and any of the transduced cells. Keratinocytes infected with the E7 retrovirus exhibited decreased levels of Rb protein and increased levels of p53, whereas cells infected with E6-expressing retroviruses displayed normal levels of Rb protein and decreased levels of p53. Finally, E7 induced a three-fold increase in bcl-2 expression. Our results indicate that the HPV-16 E7 gene alone is sufficient to bypass keratinoctye growth arrest induced by serum and calcium exposure and that the discordant expression of several cell regulatory proteins accompanies this unregulated proliferation.      

一种新的网霉素银染法

0　引言　组织学上曾将结缔组织分为网霉素 (reticulin)和胶原蛋白 .但现已将网霉素归于胶原蛋白的 6型之一 ,被命名为 型胶原蛋白 ,基底膜属于 型胶原蛋白 [1 ] .有几种浸银技术可显示网霉素和基底膜 [2 ] .但只能显示一种颜色 ,不能将 6种类型胶原蛋白区别开 .我们通过添加氧化剂、调色剂 ,网霉素的浸银技术可将 型和 型胶原蛋白染成紫红色 , ～ 型胶原蛋白 ,基底膜 ,纤维粘连蛋白和细的神经纤维都染成黑色 .网霉素的染色对于揭示一些疾病的病理过程有重要作用 .我们经实验 ,用一种新的银染法对肝、肾、脾、淋巴结等进行了染色 ,取得…     

缩宫素联合米索前列醇预防产后出血

1 临床资料 2003-02/2004-08单胎足月妊娠阴道分娩者1210例,分为研究组720例,对照组490例.研究组于第2产程末,建立静脉通路,缓慢静滴50 g/L葡萄糖液＋缩宫素2.5 U维持;在胎头娩出前,舌下含化米索前列醇400～600 μg,使其自然溶解;胎头娩出后续加缩宫素2.5 U静滴.     

尼莫地平片剂生物利用度和健康人药代动力学研究

用高效液相色谱法测定了6名健康志愿者口服二种尼莫地平片剂的相对生物利用度和药代动力学参数。结果表明:尼莫地平在人体内的浓度—时间数据可用一室开放模型拟合,主要动力学参数与国外文献报道一致。新片剂和普通片的人体相对生物利用度分别为82.39%和16.01%。     

RNA干扰技术与结肠癌

RNAi技术具有特异性和高效性,已经成为研究基因功能的重要工具,在肿瘤的治疗中发挥重要作用,但同时也存在其不足.现就近年来RNAi在结肠癌的基因治疗中的运用作一综述.     

血液灌流在皮肤科的应用近况

血液灌流对许多慢性、顽固性和疑难性疾病有较好疗效，但在皮肤科的应用仅局限于银屑病、系统性红斑狼疮（SEE）等少数几个病种。在自身免疫相关性皮肤病方面，血液灌流有独特的治疗效果和广阔的应用前景，现将近年相关文献作一综述。     

双波长紫外分光光度法测定盐酸普鲁卡因溶液的含量

目的：为准确测定盐酸普鲁卡因溶液的含量。方法;采用双波长分光光度法测定盐酸普鲁卡因溶液的含量,测定波长为２８９ｎｍ,参比波长为２５９．７ｎｍ。结果;平均回收率为１００．７％,ＲＳＤ＝１．０６％。结论：本方法能有效地消除盐酸普鲁卡因分解产物对氨基苯甲酸的干扰,准确测得其真实含量。     

新型全固态阿托品电极的研制

制备了以脲醛树脂为框架,以KCl粉末为活性组分的Ag/AgCl固体电极。以此固体电极为基体,以阿托品—四苯硼酸根离子缔合物为活性物质,研制了一种新型全固态阿托品选择电极。并对此电极的性质进行了研究,结果表明该电极稳定性较好,并能用于硫酸阿托品制剂的含量测定。     

Stable overexpression of PML alters regulation of cell cycle progression in HeLa cells

Our previous studies demonstrated that PML is a growth suppressor that suppresses oncogenic transformation of NIH/3T3 cells and rat embryo fibroblasts. PML is a nuclear matrix-associated phosphoprotein whose expression is regulated during the cell cycle. Disruption of PML function by t(15;17) in acute promyelocytic leukemia (APL) plays a critical role in leukemogenesis. To further study the role of PML in the control of cell growth, we have stably overexpressed PML protein in the HeLa cell line. This overexpression of PML significantly reduced the growth rate of HeLa cells and suppressed anchorage-independent growth in soft agar. We consequently investigated several parameters correlated with cell growth and cell cycle progression. We found that, in comparison with the parental HeLa cells, HeLa/PML stable clones showed proportionally more cells in G1 phase, fewer cells in S phase and about the same number in G2/M phase. The HeLa/PML clones showed a significantly longer doubling time as a result of a lengthening of the G1 phase. No effect on apoptosis was found in HeLa cells overexpressing PML. This observation indicates that PML suppresses cell growth by increasing cell cycle duration as a result of G1 elongation. To further understand the mechanism of the effect of PML on HeLa cells, expression of cell cycle-related proteins in HeLa/PML and parental HeLa cells was analyzed. We found that Rb phosphorylation was significantly reduced in PML stable clones. Expression of cyclin E, Cdk2 and p27 proteins was also significantly reduced. These studies indicate that PML affects cell cycle progression by mediating expression of several key proteins that normally control cell cycle progression. These results further extend our current understanding of PML function in human cells and its important role in cell cycle regulation.