人晶体 γ-晶体蛋白的研究:Ⅳ.近紫外线对胚 γ_2-晶体蛋白的光氧化作用

对人胚胎晶体γ_2-晶体蛋白溶液用近紫外线(γmax 365nm)照射,不同时间取样分析。利用巯基(-SH)特异性试剂 DACM[N-(7-甲基氨基-4-甲基-3-邻羟苯烯基)-马来酰亚胺],经 SDS-聚丙烯酰胺凝胶电泳观察光照射后的γ_2-晶体蛋白及其聚合物的游离巯基,同时检测照射后的蛋白溶液的紫外吸收光谱、光散射强度、色氨酸荧光发射光谱,以及丙烯酰胺对色氨酸荧光的猝灭效应。结果显示:人胚胎γ_2-晶体蛋白经紫外线照射,使其游离-SH 减少,蛋白聚合和分解,蛋白溶液的光散射增强,其二聚体不含游离-SH,γ_2-晶体蛋白的色氨酸荧光减少,这些变化随照射时间的延长而更明显;而对丙烯酰胺对蛋白分子中的色氨酸荧光猝灭效应影响不大。说明人胚胎γ_2-晶体蛋白通过光氧化,损伤及含游离-SH 的氨基酸残基、色氨酸残基,光氧化促使蛋白聚合和分解.提出通过进一步定量分析,可能在较深层次揭示紫外光氧化损伤含-SH 氨基酸、色氨酸残基,进而影响整个蛋白质分子结构的差异。眼科学报 1993;9:85-89。     

Ligase chain reaction for diagnosis of familial hypertrophic cardiomyopathy

ＬｉｇａｓｅｃｈａｉｎｒｅａｃｔｉｏｎｆｏｒｄｉａｇｎｏｓｉｓｏｆｆａｍｉｌｉａｌｈｙｐｅｒｔｒｏｐｈｉｃｃａｒｄｉｏｍｙｏｐａｔｈｙＳｕｎＷｅｉｄｏｎｇ孙维东，ＨａｎｓｅｌＳｔｅｄｍａｎ，ＣｈｅｎＸｉａｏｌｉ，ＷｅｉＹｕ，ＬｉｕＭｅｉｚｈｅｎ，Ｘｕ...     

三种氨基酸对兔血浆皮质酮浓度的影响

侧脑室注射甘氨酸使健康家兔和烧伤家兔血浆皮质酮浓度降低;注射L—谷氨酸和L—天冬氨酸使健康家兔血浆皮质酮浓度升高,但不能使烧伤后升高的血浆皮质酮浓度发生改变。提示这三种氨基酸作为神经递质参与下丘脑—垂体—肾上腺皮质轴的调控。烧伤刺激通过下丘脑引起内分泌紊乱,这种紊乱与L—谷氨酸和L—天冬氨酸失控有关。     

妇科腹腔镜手术几种激光对兔子宫壁损伤的实验研究

为掌握妇科腹腔镜手术所应用的激光器的治疗剂量，对几种激光引起的兔子宫壁热损伤进行观察。实验研究证实：所有激光产生的损伤程度与所用的剂量呈正相关。术后４８ｈ与即刻损伤程度相比，半导体激光的损伤程度明显加深、加宽；但ＣＯ２激光和ＮｄＹＡＧ激光接触式光刀无显著变化。说明应用激光行妇科腹腔镜手术治疗时，所产生的损伤与应用的功率密度有关，为临床合理选用腹腔镜下的激光治疗提供依据     

日本血吸虫感染小鼠脾细胞IL—2及IFN—γ动态观察

本文观察８ｗｋ龄Ｃ５７ＢＬ／６小鼠感染日本血吸虫尾蚴后不同时期脾细胞经ＳＥＡ或ＣｏｎＡ刺激，体外诱生的ＩＬ－２和ＩＦＮ－γ活性变化。结果表明两种细胞因子活性均在感染后第４－６ｗｋ开始上升，第６—８ｗｋ达高峰，第１２—１４ｗｋ恢复至感染前水平。ＩＦＮ－γ高峰时间略先于ＩＬ－２。非特异性刺激原诱生组和特异性刺激原诱生组各阶段细胞因子活性动态基本一致，前组活性高于后组。提示ＩＦＮ－γ与ＩＬ－２活性与血吸虫卵肉芽肿的诱导、成熟与维持有密切关系。     

肟类药物对塔崩等神经性毒剂抑制的大鼠脑AChE的体外重活化作用

系统地研究了肟类药物对塔崩抑制的大鼠脑AChE的体外重活化作用,并与梭曼、沙林和VX进行了比较。结果表明,沙林和VX抑制的AChE较易被药物重活化,而塔崩和梭曼抑制的AChE则较难。37℃、pH7.2条件下,塔崩抑制的大鼠脑AChE可浓度依赖性地被TMB_r和LuH_6重活化,2-PAM在高浓度下也有一定作用,但HI-6在所用3个浓度下均无重活化。通过降低抑制温度成功地建立了未老化的梭曼膦酰化AChE模型。药物试验表明,未老化的梭曼膦酰化大鼠脑AChE可被高浓度(1mmol/L)HI-6重活化,而不被2-PAM、TMB_4及LuH_6重活化。提示药物自身内在活性在重活化作用中的重要性。TMB_4和LuH_6对塔崩磷酸化AChE有较强重活化,而对未老化梭曼膦酸化AChE无重活化,HI-6则相反,对未老化梭曼膦酰化AChE重活化效果好,而对塔崩磷酰化AChE无重活化作用。塔崩和梭曼膦酰化AChE在未老化以前对药物的响应就有所不同,毒剂残基的空间效应可能起重要作用。     

采用生活垃圾研制烧结砖

该文介绍了用好氧发酵工艺对新鲜生活垃圾进行预处理,用做制砖的原料。制砖工艺采用对辊,双轴搅拌,真空挤出,轮窑烧成等工序,垃圾掺加量为30％～50％,可完全取代内掺材料,节省90％以上的煤炭。     

Microvascular corrosion casting of normal tissue, transitional mucosa and adenocarcinoma in the human colon.

The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development.     

Structure-activity relationships of (+)-CC-1065 analogues in the inhibition of helicase-catalyzed unwinding of duplex DNA.

(+)-CC-1065 is a potent antitumor antibiotic produced by Streptomyces zelensis. Previous studies have shown that the potent cytotoxic and antitumor activities of (+)-CC-1065 are due to the ability of this compound to covalently modify DNA. (+)-CC-1065 reacts with duplex DNA to form a (N3-adenine)-DNA adduct which lies in the minor groove of DNA overlapping with a five base-pair region. As a consequence of covalent modification with (+)-CC-1065, the helix bends into the minor groove and also undergoes winding and stiffening. In the studies described here, we have constructed templates for helicase-catalyzed unwinding of DNA that contain site-directed (+)-CC-1065 and analogue DNA adducts. Using these templates we have shown that (+)-CC-1065 and select synthetic analogues, which have different levels of cytotoxicity, all produce a significant inhibition of unwinding of a 3'-tailed oligomer duplex by helicase II when the displaced strand is covalently modified. However, the extent of helicase II inhibition is much more significant for (+)-CC-1065 and an analogue which also produced DNA winding when the winding effects are transmitted in the opposite direction to the helicase unwinding activity. This observed pattern of inhibition of helicase-catalyzed unwinding of drug-modified templates was the same for a 3'-T-tail, for different duplex region sequences, and with the Escherichia coli rep protein. Unexpectedly, the gel mobility of the displaced drug-modified single strand was dependent on the species of drug attached to the DNA. Last, strand displacement by helicase II coupled to primer extension by E. coli DNA polymerase I showed the same pattern of inhibition when the lagging strand was covalently modified. In addition, the presence of helicase II on single-stranded regions of templates caused the premature termination of primer extension by DNA polymerase. These results are discussed from the perspective that (+)-CC-1065 and its analogues have different effects on DNA structure, and these resulting structural changes in DNA molecules are related to the different in vivo biological consequences caused by these drug molecules.     

持续无痛快速扩张法及其临床应用

介绍了一种持续无痛快速注水法,即以疼痛开始为超负荷标准的满负荷扩张法。利用自行设计的注水装置,将扩张器内压始终控制在病人的疼痛阈值水平,维持注水速率和皮肤扩张速率的动态平衡。本法注水既非均速也非恒压。13例19个扩张器采用本法注水,5～20天完成。所需时间长短的差别取决于扩张器大小、部位、所扩张皮肤面积的大小及病人的敏感性。我们在详细比较和探讨了各种快速注水方法的基础上,提出了满负荷扩张法的特点和理论依据。