首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Parascript II?     
  相似文献   

2.
3.
4.
本文是作者贵州灵芝科研究的第二报。报道4个种,其中3个是新种。它们及其特征是:白边灵芝Ganoderma alblmarglnatum He,该种的菌盖红褐色至褐色,边缘白色,菌肉上层木材色,近菌管层淡褐色,菌管表面淡黄色,孢子较大(9.5一13.4×6.7—8.8μm)。它与闽南灵芝(G.Austrofujia-nense Zhao,Xu et Zhang)的区别为后者菌盖乌黑色或黑褐色,具污白色和褐色相间的环带,菌肉褐色,管面污白色,孢子较小(5.7—10.4×3.4—5.2μm)。它与黄边灵芝(G.Luteomarginatum Zhao,Xu et Zhang)的区别为后者菌盖黑褐色到暗褐色,边缘黄褐色,孢子较小(8.7一10.4×5.2—7μm)。兴义灵芝Ganoderma xingyiense He,该种的特征是菌盖近肾形,锈红色,似漆样光泽弱,有显著的辐射状纵皱,边缘稍钝,不整齐,波状;菌柄偏生到侧生,紫褐色,有强烈的似漆样光泽。尚未见有类似种类。拟层状灵芝 Ganoderma stroto-ideum He,该种的特征是子实体有柄,菌盖近漏斗状,表面乌红黑色,拟层状,具有光泽和无光泽相间的同心环带,菌肉厚达1cm,上层木材色,近菌管层淡褐色。它近于中国灵芝(G. sinense Zhao.Xu et Zhang),但后者菌盖非漏状,表面紫褐色并且非拟层状,菌肉均匀褐色,菌柄紫褐色。 以上所引证的标本保藏于贵州科学院生物研究所真菌标本室。  相似文献   

5.
云木香化学成分研究 II   总被引:7,自引:0,他引:7  
从丽江产云木香(SaussrealappaC.B.Clarke)根中分离得到的另外7化合物,它们分别是孕甾炮醇酮(pregnenolone)(1),β-谷甾醇(β-sitosterol)(2)葫萝卜甙(daucosterol)(3),苯丙素甙(syringin)(4),木质素甙(1-hydroxypinoresinol-1-β-D-glucopyranoside)(5)油酸(z,z)-9,12-o  相似文献   

6.
Potentiometric, visible, and infrared studies of the complexation of N-(2-acetamido)-2-aminoethanesulfonic acid (ACESH) by Ca(II), Mg(II), Mn(II), Co(II), Zn(II), Ni(II), and Cu(II) are reported. Ca(II), Mg(II), and Mn(II) were found not to complex with ACES?, while Co(II), Zn(II), Ni(II), and Cu(II) were found to form 2:1, ACES? to M2+, complexes, and [Cu(ACES)2] was found to undergo stepwise deprotonation of the amide groups to form [Cu(H?1ACES)22?]. Formation (affinity) constants for the various metal complexes are reported, and the probable structures of the various metal chelates in solution are discussed.  相似文献   

7.
Derivatives of Co(II), Ni(II), Cu(II) and Zn(II) with 3′AMP and 2′AMP were synthesized and characterized by IR UV-Vis and fluorescence spectroscopy. There seems to be bonding of the metal ion to the base in all cases. The activation test, using the complexes as allosteric labels, was carried out with rabbit muscle glycogen phosphorylase b, but the enzyme was not activated, confirming that the phosphate group must necessarily be bonded to position 5′ of the ribose in order to activate this enzyme.  相似文献   

8.
9.
Etoposide is an anticancer drug that acts by inducing topoisomerase II-mediated DNA cleavage. Despite its wide use, etoposide is associated with some very serious side-effects including the development of treatment-related acute myelogenous leukemias. Etoposide targets both human topoisomerase IIα and IIβ. However, the contributions of the two enzyme isoforms to the therapeutic vs. leukemogenic properties of the drug are unclear. In order to develop an etoposide-based drug with specificity for cancer cells that express an active polyamine transport system, the sugar moiety of the drug has been replaced with a polyamine tail. To analyze the effects of this substitution on the specificity of hybrid molecules toward the two enzyme isoforms, we analyzed the activity of a series of etoposide-polyamine hybrids toward human topoisomerase IIα and IIβ. All of the compounds displayed an ability to induce enzyme-mediated DNA cleavage that was comparable to or higher than that of etoposide. Relative to the parent drug, the hybrid compounds displayed substantially higher activity toward topoisomerase IIβ than IIα. Modeling studies suggest that the enhanced specificity may result from interactions with Gln778 in topoisomerase IIβ. The corresponding residue in the α isoform is a methionine.  相似文献   

10.
A new ligand N-Nicotinoyl-N-o-hydroxythiobenzhydrazide (H2Notbh) forms complexes [Mn(Notbh)(H2O)], [M(Notbh)] [M=Ni(II) Cu(II) and Zn(II)] which were characterized by various physico-chemical techniques. All the metal complexes were observed to inhibit the growth of tumor in vitro, whereas, ligand did not. In vivo administration of these complexes resulted in prolongation of survival of tumor bearing mice. Tumor bearing mice administered with metal complexes showed reversal of tumor growth associated induction of apoptosis in lymphocytes. The paper discusses the possible mechanisms and therapeutic implication of the H2Notbh and its metal complexes in tumor regression and tumor growth associated immunosuppression.  相似文献   

11.
Roentgen findings in 107 girls under the age of ten years who had proven recurrent urinary tract infections were analyzed. From the excretory urograms done on these children, renal and pelvocalyceal outlines were accurately traced. Subsequently, renal length and parenchymal thickness at multiple points were measured. The presence or absence and grade of reflux were determined by voiding cystourethrography. Finally, the clinical history was correlated with the roentgen findings.With three exceptions, scarring and clubbing in the presence of infection occurred only in refluxing renal units. Kidneys exposed to a higher grade of reflux more frequently showed scarring and clubbing (p<0.001). Seventeen out of 40 renal units either developed or had increase in clubbing and scarring while the patients were being followed. After surgical correction of reflux, 16 of 24 previously clubbed and scarred kidneys showed progression of the lesions, usually within 24 months after operation. All children whose kidneys showed progression after surgical operation had experienced an episode of acute urinary infection with chills and fever before operation.No significant difference existed in the age at clinical onset of infection in patients with ureteral reflux with or without roentgen evidence of clubbing and scarring. This study documents the close relationship between clubbing and scarring and reflux in the presence of urinary infection in infants and children.  相似文献   

12.
13.
14.
15.
16.
N-Salicyloyl-N-p-hydroxythiobenzohydrazide (H2STPH) and N-benzoyl-N-thiobenzohydrazide (H2BTBH) and their Co(II), Ni(II), Cu(II) and Zn(II) complexes were prepared and characterized by physicochemical studies. IR and NMR spectral studies imply dibasic tetradentate behaviour of the ligands bonding through `thiolato' sulfur, enolic oxygen and the two hydrazinic nitrogens in a polymeric fashion. The electronic spectra indicate [Ni(STPH)(H2O)2], [Co(STPH)(H2O)2] to be distorted octahedral while [Cu(BTBH)] has a square-planar geometry. In vitro antitumor results of the ligand and the complexes on P-815 (murine mastocytoma) and L-929 (murine fibroblast) indicate that these compounds show significant inhibition of 3H-thymidine and 3H-uridine incorporation in DNA and RNA, respectively, in these tumor cells at dose levels of 1, 2.5 and 5 g cm–3. Antitumor studies suggest that [Cu(BTBH)] has significant dose dependent inhibitory effect on DNA synthesis. In vivo administration of [Cu(BTBH)] and [Ni(STPH)(H2O)2] resulted into prolongation of life span of Dalton's Lymphoma (DL) bearing mice.  相似文献   

17.
The Developmental Systems approach to evolution is defended against the alternative extended replicator approach of Sterelny, Smith and Dickison (1996). A precise definition is provided of the spatial and temporal boundaries of the life-cycle that DST claims is the unit of evolution. Pacé Sterelny et al., the extended replicator theory is not a bulwark against excessive holism. Everything which DST claims is replicated in evolution can be shown to be an extended replicator on Sterelny et al.s definition. Reasons are given for scepticism about the heuristic value claimed for the extended replicator concept. For every competitive, individualistic insight the replicator theorist has a cooperative, systematic blindspot.  相似文献   

18.
芒果叶化学成分研究 II   总被引:1,自引:0,他引:1  
为探讨芒果(Mangifera indica L.)的化学成分,从芒果叶的70%乙醇提取物中分离鉴定了13个化合物,经波谱分析,分别鉴定为:(–)-secoisolariciresinol-9′-O-D-glucopyranoside(1)、7S,8R-erythro-4,7,9-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-β-D-glucopyranoside(2)、7R,8R-threo-4,7,9-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-β-D-glucopyranoside(3)、(7R/S,8R)-7,8-dihydro-9′-hydroxyl-3′-methoxyl-8-hydroxymethyl-7-(4-hydroxy-3-methoxyphenyl)-1′-benzofuranpropanol 9′-O-β-D-glucopyranoside(4)、citrusin D(5)、丁香苷(6)、2,6-二甲氧基-4-羟基苯基-1-O-β-D-葡萄糖苷(7)、原儿茶酸(8)、没食子酸(9)、没食子酸甲酯(10)、没食子酸乙酯(11)、4,5-二羟基-3-甲氧基苯甲酸(12)、β-胡萝卜苷(13)。其中化合物1~7和12为首次从芒果属植物中分离得到。  相似文献   

19.
哺乳动物肺泡上皮细胞主要由肺泡II型上皮细胞(AECII)和肺泡I型上皮细胞(AECI)组成。在肺发育和肺损伤修复过程中,AECII可转分化为AECI,体外原代培养的AECII有这种转分化的特性。现对AECII转分化的标志、影响及调控因素及其在肺损伤中的作用进行综述。  相似文献   

20.
II类内含子的研究进展   总被引:1,自引:0,他引:1  
自1977年以来,发现绝大多数真核生物的基因都是不连续的,即在编码序列中间有一个或数个间插序列(intervening sequence,IVS),前者被称为外显子(exon),后者被称为内含子(intron)。在DNA转录时,外显子和内含子的全部序列都被转录,形成前体mRNA。然后经过转录后加工,引入5′端帽子结构,3′端加上一段多聚腺苷酸。再经过剪接,去除不翻译的间插序列,把翻译部分连成一条链,形成成熟的mRNA。而原核生物的基因转录成mRNA,随即翻译成蛋白质,基因是连续的,在转录和翻译的过程中不需要剪接。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号