银杏内酯类合成物F抗血小板激活因子和组织胺的实验研究

目的：研究银杏内酯类化合物Ｆ（简称药物Ｆ）同时拮抗组织胺（ＨＡ）和血小板激活因子（ＰＡＦ）的作用。方法：测定离体豚鼠肺组织的收缩率以及用药物Ｆ后的致敏豚鼠肺功能的变化。结果：（１）加入药物Ｆ后离体豚鼠的气管条和肺条对ＨＡ的收缩率分别由（５０．９７±１６．００）％和（５４．２４±１２．１７）％降至（２１．６９±３．８５）％和（２２．９７±１７．７８）％（Ｐ〈０．０５）；（２）药物Ｆ保护后，离体豚鼠肺     

恶性肿瘤淋巴管生成与转移的研究进展

淋巴道转移是肿瘤转移的重要途径,也是判断预后的重要依据. 随着淋巴管生成因子及许多淋巴管特异性标记物的发现,肿瘤新生淋巴管调控与淋巴道转移机制研究得以深入开展. 大量的研究发现,恶性肿瘤和瘤周组织内存在新生的淋巴管,新生的淋巴管密度和淋巴管标记物的表达强度均与淋巴结转移密切相关. 这为揭示恶性肿瘤淋巴道转移机制和开发淋巴管靶向治疗提供了重要的研究途径. 现就近年来肿瘤淋巴管生成与转移的研究进展作一综述.     

Myocardial infarct size quantification by MR imaging early after coronary artery occlusion in dogs

The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium.     

Cloning and expression of the gene involved in Sanfilippo B syndrome (mucopolysaccharidosis III B)

Sanfilippo B syndrome is caused by a deficiency of alpha-N- acetylglucosaminidase, a lysosomal enzyme involved in the degradation of heparan sulphate. Accumulation of the substrate in lysosomes results in degeneration of the central nervous system with progressive dementia often combined with hyperactivity and aggressive behaviour. In order to clone the deficient gene, we purified the enzyme from human placenta and obtained amino acid sequence information. Alignment of one of the CNBr generated internal peptides to sequence from the database revealed the chromosomal location of the gene in the 5' upstream flanking region of the gene for 17-beta-hydroxysteroid-dehydrogenase at 17q21.1. The available DNA sequence was used to clone the cDNA coding for alpha-N- acetylglucosaminidase and analyse its gene structure. The gene is fully contained in the 5' upstream flanking region of the gene for 17-beta- hydroxysteroid-dehydrogenase and interrupted by five introns. The cDNA clone has a length of 2575 bp and encodes a protein of 743 amino acids. Chinese hamster ovary cells transfected with the cDNA construct show alpha-N-acetylglucosaminidase activity about 17-fold over background. This will allow correction studies with NAG deficient Sanfilippo B cell lines and facilitate the development of enzyme replacement therapy for these patients.      

灵芝生物碱甲和乙的合成

灵芝为担子菌类多孔菌科灵芝属植物的子实体。人工培养的有赤芝、紫芝、薄盖灵芝和树舌等。灵芝是我国广泛流传的珍贵药物之一。近年来,对于灵芝的临床疗效和药理作用做了多方面的研究,证明对慢性气管炎、慢性肝炎、冠心病、白细胞减少症、慢性克山病和神经衰弱等都有一定的疗效,特别是对神经系统和肝脏功能具有调节作用。深层培养的薄     

大花紫玉盘中新多氧取代环己烯类的结构鉴定

从番荔枝科紫玉盘属植物大花紫玉盘( Uvaria grandiflora Roxb.)根茎中分得4种新的多氧取代环己烯及已知化合物zeylenol,应用波谱分析、X-射线衍射、园二色谱和 Mosher 酯制备等手段确定了全部新化合物的结构及其绝对构型,分别命名为大花紫玉盘醇A(1),B(2),E(3)和F(4)。