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1.
长果升麻的化学成分研究   总被引:4,自引:0,他引:4  
从长果升麻(Souliea vaginata)根茎中分离出6种皂甙,经光谱(FAB-MS、1H-NMR、1H-1H-COSY、13C-NMR、1H-13C-COSY)分析,分别鉴定为27-deoxyactein(1),actein(2),25-0-乙酰升麻醇木糖甙(3),25-甲基升麻醇木糖甙(4),升麻醇木糖甙(5),24-acetylhydroshengmanol xyloside(6),其中  相似文献   

2.
番荔枝化学成分研究(7)   总被引:1,自引:0,他引:1  
从番荔枝(Annona squamosa L.)种子中得到化合物1、2和4,化合物2和4分别为已知化合物motrilin(莫垂林,2)和bullatanocin(布拉他诺辛,4)。化合物1的化学结构经IR、MS、^1H NMR及^13C NMR谱分析及其乙酰化物(1a)的MS、^1H NMR谱分析推定如(1)式并命名为22-表-莫维查灵(22-epi-molvizarin)。  相似文献   

3.
金顶侧耳多糖PC—4的结构确定与抗肿瘤活性的研究   总被引:13,自引:0,他引:13  
3%氯乙酸浸提过的金顶侧耳子实体中分离纯化另一水溶性多糖PC-4。该多糖分子量经为189kD。纸层析与气相层析分析表明其为单一聚糖。经高磺酸氧化,Smith降解,甲基化,层析,气质联机分析,核磁其振(H-NMR,13C-NMR)谱及红外光谱测定等,可确定C-4的主链结构由β-(1→3)糖苷键相连的葡萄糖构成,部份残基C6,上带有分支。约每5个糖残基有两个侧链,侧链仅为1个葡萄糖残基。  相似文献   

4.
抗丙肝病毒核心抗原单克隆抗体的研制与初步鉴定   总被引:2,自引:0,他引:2  
用基因工程重组技术获得的丙肝病毒(HCV)核心蛋白抗原与鼠血清白蛋白交联后免疫Balb/c小鼠,用杂交瘤技术成功地建立了4株稳定分泌抗核心抗原单克隆抗体的杂交瘤细胞,试验结果表明,该4株McAbs与免疫抗原及核心区C33肽、CP9、CP10抗原有较强的抗原-抗体反应,与HCV NS3、NS4、NS5无反应,在竞争ELISA中,对HCV-IgG阳性血清有较好的抑制作用。4株McAbs中3株为IgG2  相似文献   

5.
5—羟色胺对肺动脉平滑肌细胞在缺氧条件下增殖的作用   总被引:2,自引:1,他引:1  
刘健  王培勇 《生理学报》1997,49(3):292-298
本研究应用细胞培养、^3H-TdR掺入,核酸分子杂交、免疫组织化学染色技术,探讨无氧(0%O2+95%N2+5%CO2)和/或低氧(2.5 ̄3%O2+92%N2+5%CO2)对新生小牛肺动脉平滑肌细胞增殖和5-羟色胺转载体基因表达的影响。结果表明:无氧24h可刺激PASM的DNA合成,^3H-TdR的掺入增加(P〈0.05),加入5-羟色胺能非常显著地促进无氧PASM增殖(P〈0.001),而对常  相似文献   

6.
曼氏血吸虫(Schistosomamansoni)和日本血吸虫(S.japonicum)成虫和曼氏血吸虫尾蚴基因组DAN经限制性内切酶BamHI消化后,分别与^32p-dCTP标记的来源于核糖体DNA的PSMHCR5、PSMHCR4PSM889探针杂交,曼我血吸虫尾蚴和成虫在PSMHCR4杂交带型的1.6-2.8kb之间,存在有明显不同的次杂带;而PSMHCR5和PSM889的杂交带型,无明显差异  相似文献   

7.
应用蛋白dotblot技术检测了低氧内皮细胞条件培养液(HECCM)和常氧内皮细胞条件培养液(NECCM)内PDGF相对含量,并利用[3H]-TdR掺入法和流式细胞术观察了HECCM和NECCM及加入特异PDGF抗体对肺动脉平滑肌细胞(PASMC)生长的影响。结果表明,HECCM中的PDGF含量明显高于NECCM;HECCM能明显增强PASMC内DNA合成,促进PASMC从Go/G1期进入S期;当预先加入PDGF-B链抗体时,则会明显地抑制HECCM对PASMC的DNA合成,阻止PASMC从Go/G1期进入S期。结果提示,低氧时PASMC增殖与肺动脉内皮细胞分泌释放PDGF增加有关  相似文献   

8.
双丁酰环烯酸腺苷对人肝癌细胞株SMMC—7721表面N—糖…   总被引:2,自引:0,他引:2  
本文采用系列凝集素柱层析法,并配合外切糖苷酶研究了在双丁酰环磷酸腺苷(dB-cAMP)作用1-5过程中人肝癌细胞株SMMC-7721细胞表面N-糖链类型及复杂型糖链天线数的变化。结果表明,dB-cAMP促进^3H-Man参人细胞表面N-糖链,使高甘露糖型N-糖链的百分比下降,并促进二天线N-糖链的生物合成,使多天线特别是四天线和C2C2C6三天线N-糖链的百分比减少。结果提示,N-糖链结构的这些变  相似文献   

9.
中国伞滑刃线虫属─新纪录(真滑刃目:寄生滑刃科)   总被引:1,自引:0,他引:1  
中国伞滑刃线虫属─新纪录(真滑刃目:寄生滑刃科)THENEWRECORDOFBURSAPHELENCHUSFROMCHINA(APHELENCHIDA:PARASITAPHELENCHIDAE)¥YINGan-liu;FANGYu-sheng(Dep...  相似文献   

10.
乳酸脱氢酶C4的精子免疫荧光定位特性   总被引:2,自引:0,他引:2  
用14个抗小鼠LDH-C4的单克隆抗体对小鼠、树鼯和人精子的LDH-C4进行了间接免疫荧光定位。结果显示:不同的单抗可以结合到小鼠精子表面不同的位置,其中PA1(K021)在尾部,PA2(K022)、PA4和PA5(K023)在中段和尾部,SM1、SM2和PG2的中段,SM3和SM4在顶体,SM5在顶体和赤道板。人和树鼯精子表面的LDH-C4也呈现类似的情况。这些研究表明精子表面的LDH-C4呈现  相似文献   

11.
Riassunto Lo studio comprende una revisione critico-sperimentale della specie Actinomyces albus, della quale vengono considerati come sinonimi circa 30 nomi speeifici, fra i quale A. chromogenus, A. odorifer, A. thermophylus p.p.; della specie é data una diagnosi ed una particolareggiata descrizione.Sono inoltre studiate le specie A. viridis, (= A. viridochromogenus) e A. innominatus, n. nomen. Quest'ultima é preceduta da una breve discussione sulla specie A. homini.
Summary Twenty-six strains of Actinomyces albus are studied redescribed from morphological, cultural and biochemical standpoints. Many biological activities of A. chromogenus, A. odorifer and A. thermophilus are in common with other species of the same genus, so that they may be considered for sub-specific, (not specific) differentiation. A discussion on A. farcinicus, A. albidoflavus and A. aureus has been originated from mislabeling as A. albus; the group including the two last named species (flavus group) must be revised. A few strains classified A. farcinicus are in no doubt true A. albus, but this real specific entity remains to be revised from Nocard's strain. A. viridis, for the first time described by Lombardo-Pellegrino, has been redescribed three times as a new species under the same binomial, and the fourth as A. viridochromogenes. A. hominis Bostroem is an uncorrect determination for the species originally described by Waksmann and Curtiss, and it is renamed A. innominatus, the binomial A. (Streptothrix) hominis Auct. being a nomen ambiguum. In conclusion, 30 bionmial are appended in sinonimy to A. albus, including Cladothrix dichotoma Macé (1888) non Cohn, G. invulnerabilis Acosta et G. Rossi, C. odorifera Rullm. Actinomyces chromogenus Gasp., A. thermophilus Auct., p.p., A. (Streptothrix) Sanninii (Cif.) Westerd., A. Almquisti Duché, A. Gougeroti Duché, and so on.
  相似文献   

12.
High levels of nuclease activities were identified in filtrates ofAspergillus cultures after growth in low- but not in high-phosphate media. Deoxyribonuclease activities, characterized extensively by column chromatography, showed a coincident single peak for ss- and ds-DNase which was distinct from the peak for RNase. Both ss-DNase and ds-DNase are endonucleolytic and showed the highest activity in the presence of Ca2+ and Mn2+ (atpH 8.0). They also showed identical heat sensitivities suggesting that a single, phosphate-repressible DNase was secreted. This enzyme, therefore, corresponds to the well-characterized extracellular DNase A ofNeurospora. However, theAspergillus DNase A did not cross-react with antisera to secretedNeurospora nucleases and showed different chromatographic properties, and active peptides of different sizes were visualized on DNA activity gels. The increasing derepression ofAspergillus DNase A by decreasing phosphate levels was similar to that of secreted alkaline phosphatase and these increases were both abolished by the regulatory mutantpalcA. This investigation was supported by Grant A2564 from the Natural Science and Engineering Research Council of Canada.  相似文献   

13.
Two β-glucosidases, G1 and G2, were purified from the culture supernatant of Penicillium herquei Banier and Sartory. Both the purified enzymes were homogeneous on polyacrylamide disc gel electrophoresis. The molecular weights of G1 and G2 were estimated to be 125,000 and 122,000, respectively, by sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis. G1 and G2 contained 12.7% and 16.1% carbohydrate as glucose, and had isoelectric points of 5.02 and 5.24, respectively. Both enzymes had optimum pHs of 4.0~4.5 and optimum temperatures at 60°C, but pH - and thermo-stabilities of G1 were higher than those of G2. Both enzymes were active not only on p-nitrophenyl β-d-glucopyranoside, salicin, and the p-glucobioses tested but also on laminarin. CM-Cellulose was a very poor substrate for both enzymes. The activities of G1 toward the substrates except for laminarin and CM-cellulose were apparently higher than those of G2. Both enzymes acted on cellobiose to produce a transfer product.  相似文献   

14.
15.
六种鲟鱼消化酶活性的比较研究   总被引:13,自引:1,他引:12  
测定了两个生长阶段 6种鲟鱼幼鱼胃、肠道和肝脏中蛋白酶、脂肪酶、淀粉酶活性。幼鲟消化酶活性在两个生长阶段变化不明显。 6种鲟鱼不同消化器官蛋白酶活性以肠道为最高 ,肝脏为最低 ,肝脏中的蛋白酶活性明显低于胃、肠道 (P <0 0 1)。不同消化器官脂肪酶活性 ,以肠道为最高 ,且肠道脂肪酶活性显著高于胃、肝脏 (P <0 0 1) ,胃中的脂肪酶活性与肝脏中的脂肪酶活性差异不明显 (P >0 0 5 )。不同消化器官淀粉酶活性 ,以肠道为最高 ,且明显高于胃、肝脏 (P <0 0 1)。幼鲟在第一阶段 ,肝脏中没有淀粉酶活性 ,其活性出现在第二阶段 ,且在此生长阶段 ,肝脏中的淀粉酶活性达到胃中的水平 (P >0 0 5 )。对 6种鲟鱼而言 ,除个别存在较大差异外 ,3种消化酶活性大体上都没有明显差异  相似文献   

16.
Patterns of intraspecific variation were examined inAntennaria alborosea A. E. Porsild,A. corymbosa E. Nels,A. marginata Greene,A. microphylla Rydb.,A. parvifolia Nutt., andA. umbrinella Rydb. AlthoughA. alborosea was initially considered arctic in distribution, it became apparent that a southern montane element also exists. Our results suggest that morphological differences between arctic and southern montane specimens represent clinal variation. The additional morphological data for specimens that occur more than 1,500 km south of the species' range as it was initially described result in a better understanding of this once presumed arctic taxon. Morphological variation in the dioecious speciesA. corymbosa, A. marginata, A. microphylla, A. parvifolia, andA. umbrinella was greater between the genders than was geographic variation within each gender. These results demonstrate that both pistillate and staminate specimens must be examined in dioecious species ofAntennaria if morphological variation in the respective species is to be fully understood. Character size or number of broadly distributed species (A. microphylla andA. parvifolia) generally decreased with increasing longitude, whereas characters of species with more restricted distributions (A. alborosea, A. corymbosa, andA. marginata) generally increased in size or number with increasing latitude or longitude.Antennaria umbrinella was an exception in this respect.  相似文献   

17.
18.
Gibberellin A17, abscisic acid, and 4′-dihydrophaseic acid were identified by GC-MS of derivatized extracts from both immature and mature seeds of pear. Immature seeds also contained phaseic acid, gibberellins A25 and A45, and two presumed mono-hydroxylated derivatives of GA45, one of which was tentatively identified as 3β-hydroxy-GA45. Several presumed metabolites of abscisic acid were detected in both mature and immature seeds.  相似文献   

19.
The structures of four alkaloids extracted from Lycopodium lucidulum (Lycopodiaceae) were established by X-ray and 2D NMR spectroscopic analyses. The dihydro-derivative of oxolucidine A, which was obtained by NaBH4 reduction of oxolucidine A, was treated with p-bromobenzoyl chloride to afford crystals, whose X-ray crystallographic analysis established the stereostructure, including the absolute configuration. The 2D NMR spectra of tetrahydrodeoxylucidine B were fully analyzed to establish the full structure of lucidine B, and the hitherto unknown stereochemistry at the C-14 position was established as beta-H. The structure of a new alkaloid, lucidulinone, was determined by spectroscopic analysis to be luciduline lactam.  相似文献   

20.
Multivariate analysis of vegetative and reproductive characters was used to examine morphological relatedness amongAntennaria alborosea A. E. Porsild,A. corymbosa E. Nels.,A. marginata Greene,A. microphylla Rydb.,A. parvifolia Nutt.,A. rosea Greene, andA. umbrinella Rydb. Both pistillate and staminate plants were examined. Some of the characters examined were variable in one species, but stable in another (i.e., presence or absence of papillae on the achenes). Our analyses indicate that the seven species are morphologically distinct. It is hypothesized that theA. rosea agamic complex arose through hybridization amongA. corymbosa, A. microphylla, A. umbrinella, and possiblyA. dioica (L.)Gaertn. However, hybridization between the three former species and others, as well as their subsequent morphological responses to different environmental conditions causes confusion in recognizing the taxa.Antennaria angustifolia Rydb.,A. arida E. Nels.,A. confinis Greene,A. scariosa E. Nels.,A. foliacea humilis Rydb.,A. concinna E. Nels., andA. viscidula E. Nels. are considered to represent F 1 hybrids.  相似文献   

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