Inhibition of interleukin-1 beta release from cultured human peripheral blood mononuclear cells by prednisolone

Prednisolone, a water-soluble glucocorticoid hormone, suppressed the secretion of interleukin-1 beta from human peripheral blood mononuclear cells in culture. The prednisolone-induced suppression of the monokine release was dose-related and the half maximal response was observed at 0.1 nM.     

转基因植物生产生物可降解塑料的研究进展

塑料制品需求日益增加,传统的合成塑料废物已带来越来越严重的环境污染问题,生物可降解塑料的研制与开发迫在眉睫.聚-β-羟基丁酸酯(简称PHB)是生物可降解塑料中研究得最多的一种.为降低PHB的生产成本,提高PHB与传统塑料的市场竞争力,可向植物体内引入PHB生物合成途径.以植物为表达载体,利用CO2及光能合成PHB,是大规模廉价生产PHB的一种很有前景的方法.     

中国建设推动力的计量模型与分析研究

本研究提供了研究建设投资对国民经济增长的影响的数量方法，根据１９８０年到１９９８年的统计数据，建立了回归模型来衡量建设推动力对中国ＧＤＰ增长中的影响。它的结果不仅提供了分析建设推动和的数量模型，而且对于正确认识建筑业和基础设施在中国经济增长中的作用及与其他国家或地区的横向比较提供了依据。     

利用多因素综合相关法预测小麦赤霉病发生程度的数学模型及其应用

小麦赤霉病是一种气候流行病,其发生流行程度的轻重,主要取决于当地4月下旬到5上旬小麦抽穗开花期20天内的气候条件,如果气温适合、湿度大时,则蔓廷成灾。本文是采用多因子综合相关法,通过计算条件频率得出预报方程,其历史拟合率高达95.6％。     

一种剪力墙结构分析的32自由度和40自由度单元

提出了一种水平方向采用3次Hermite多项式，铅垂方向采用高达5次和6次的La-grange多项式作插值函数的高阶矩形剪力培平面应力问题单元，这种单元不但位移精度高，而且具有高的应力精度．对于线性分析，单元刚度矩阵各元素全部经过十分繁荣的积分运算被解析的算出，并采用数值积分进行了复核，因此计算效率特别高．     

Bicuculline and picrotoxin block gamma-aminobutyric acid-gated Cl- conductance by different mechanisms

Using isolated, internally perfused bullfrog dorsal root ganglion cells we have studied the dose-response curves for gamma-aminobutyric acid (GABA) in the presence of internally or externally applied GABA antagonists. With external application of antagonists the inhibition of the GABA current by bicuculline was competitive and that by picrotoxin was noncompetitive. Picrotoxin but not bicuculline blocked when internally perfused.     

Critical period for induction of congenital hydrocephalus and dysplasia of subcommissural organ by prenatal X-irradiation in rats

A single whole-body X-irradiation of pregnant Wistar rats at a dose of 1.05 Gy at 10.30, 12.30 and 14.30 h respectively, of gestational day 10 resulted in significantly high incidences of hydrocephalic offspring. No hydrocephalic offspring resulted from X-irradiation of pregnant rats with 1.05 Gy at 16.30 h, whereas a dose of 1.22 Gy at 16.30 h resulted in a low but statistically significant incidence of hydrocephalus. Neither 1.05 Gy nor 1.22 Gy X-irradiation of pregnant rats at 18.30 h resulted in any hydrocephalic offspring. Dysplasia of the subcommissural organ was noticed in all the hydrocephalic brains histologically examined.     

Acute toxicity of folic acid in mice

Summary The toxicity of folic acid (PGA) was studied in different inbred strains of mice. LD₅₀ values of PGA by the i.p. route showed a unique toxicity pattern. In some strains, convulsions, ataxia and weakness were observed. Histopathological study in strains S/RVCri, BDF₁, DBA/2 and DBA/2fNCri showed acute renal tubular necrosis.Acknowledgment. The authors thank Ms N. Hasgekar for her technical assistance     

Mutations in a delta 8-delta 7 sterol isomerase in the tattered mouse and X-linked dominant chondrodysplasia punctata. jderry@immunex.com.

Tattered (Td) is an X-linked, semi-dominant mouse mutation associated with prenatal male lethality. Heterozygous females are small and at 4-5 days of age develop patches of hyperkeratotic skin where no hair grows, resulting in a striping of the coat in adults. Craniofacial anomalies and twisted toes have also been observed in some affected females. A potential second allele of Td has also been described. The phenotype of Td is similar to that seen in heterozygous females with human X-linked dominant chondrodysplasia punctata (CDPX2, alternatively known as X-linked dominant Conradi-Hünermann-Happle syndrome) as well as another X-linked, semi-dominant mouse mutation, bare patches (Bpa). The Bpa gene has recently been identified and encodes a protein with homology to 3beta-hydroxysteroid dehydrogenases that functions in one of the later steps of cholesterol biosynthesis. CDPX2 patients display skin defects including linear or whorled atrophic and pigmentary lesions, striated hyperkeratosis, coarse lusterless hair and alopecia, cataracts and skeletal abnormalities including short stature, rhizomelic shortening of the limbs, epiphyseal stippling and craniofacial defects (MIM 302960). We have now identified the defect in Td mice as a single amino acid substitution in the delta8-delta7 sterol isomerase emopamil binding protein (Ebp; encoded by Ebp in mouse) and identified alterations in human EBP in seven unrelated CDPX2 patients.