Vitamin D3 inhibits proliferation and increases c-myc expression in fibroblasts from psoriatic patients

Fibroblast cultures were established from the skin of normal and psoriatic subjects. The response to 1 alpha,25-dihydroxyvitamin D3 [1,25-(OH)2D3] of each kind of cells was assessed by measuring tritiated thymidine incorporation into DNA as an index of cell proliferation. We found that both types of cells responded with a similar dose- and time-dependent inhibition of thymidine incorporation. We also studied the response of the mRNA encoding the proto-oncogene c-myc, since its level is associated to the proliferative state in many cell types. Psoriatic fibroblasts contained higher basal amounts of c-myc RNA than control fibroblasts. Addition of 1,25-(OH)2D3 to the culture medium induced a time-dependent increase of c-myc RNA in psoriatic fibroblasts but not in controls. As a control, retinoic acid had no effect in any of the two cell types. It is concluded that in primary normal human fibroblasts, c-myc RNA levels are not correlated with the proliferative state, and that there is an altered expression of this proto-oncogene in psoriasis.     

NexGen的Nx586－Pentium的又一个挑战者

本文简单介绍ＮｅｘＧｅｎ公司最新设计出的Ｎｘ５８６ＣＰＵ。它是一种８０×８６兼容的处理器，文中介绍了它的微体系结构，ＲＩＳＣ８６指令等。     

鱼类耳石扫描电镜样品制备与观察

本文介绍了一种鱼类耳石样品的扫描电镜制样方法，通过对草鱼耳石进行包埋，抛磨，并用合适的腐蚀剂处理，用ＳＥＭ成功地观察了耳石的日轮及超微结构，该方法简便易行，保证所观察耳石样品的微观结构完整与清晰。     

PTC－BaTiO_3射频溅射用靶材的制备

研究了用于射频溅射ＰＴＣ－ＢａＴｉＯ_３薄膜的厚大靶材制备工艺，所制成的靶材的室温电阻率为８００Ω·ｃｍ，ＰＴＣ效应＞１０５，平均粒径为１～３μｍ，讨论了配方中ＴｉＯ_２品种的选择、施受主添加剂的搭配与掺量以及烧成中的升降温速率对于ＰＴＣ效应的影响     

赵41断块干扰试井资料分析

对晋县凹陷41断块油田采用小直径电子压力计试井新技术，成功地进行了干扰试井。通过对观察井、激动井所得试井资料的详细分析、评价，证实了干扰井组中各井间地层的连通性，为下一步实施注水开发提供了可靠的依据。同时，进行了地层产能的分析，做出了产能预测，认为随着原油流度、产能的降低，整个断块油藏产量将快速递减。因此，提出要对油藏及时补充能量，并采取原油降粘措施等建议。     

轴齿轮断齿失效分析

通过对轴齿轮断口形貌、硬度测试及金相组织等试验进行分析表明，齿根处没有进行硬化处理造成齿根处抗疲劳性能不足是导致轴齿轮疲劳断裂的主要原因，另外齿根过渡处倒角过小，且存在纵向刀痕引起了较大应力集中也是导致轴齿轮疲劳断裂的原因。     

Influence of Manufacturing and Ripening Conditions on the Survival of Enterobacteriaceae in Manchego Cheese

The effects of cooking temperature, time and temperature of brine-salting, and temperature of ripening on the behavior of Enterobacteriaceae in Manchego cheese were studied. Fifty lots of cheese from raw ewe's milk manufactured and ripened under different conditions were investigated throughout a 60-day ripening period. Differences in pH values due to temperature-dependent whey retention accounted for the effect of cooking temperature on coliform and fecal coliform counts. Temperature of brine-salting had no effect on Enterobacteriaceae counts, but a significant effect of salting time on Enterobacteriaceae and fecal coliform counts was detected. Ripening temperature was the manufacturing variable with greatest influence (P<.01) on Enterobacteriaceae and coliform counts during the whole curing period.     

镀锌层银盐黑色钝化工艺

在含ＡｇＮＯ３０．５～１ｇ／Ｌ，ＣｒＯ３５～１０ｇ／Ｌ，Ｈ２ＳＯ４０．５～１ｍｌ／Ｌ，光泽控制剂１０～２５ｍＬ／Ｌ的钝化液中处理镀锌层，可获得结合力良好、光亮的黑色钝化膜。