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Minoru Tamura 《Curtis's Botanical Magazine》2016,33(3):261-267
Kinugasa is a monotypic genus of the family Melanthiaceae, consisting only of K. japonica, endemic to Japan. It grows in subalpine forests, often along the valleys where snow covers in winter, and is conspicuous by its large white or yellowish white petaloid outer tepals. 相似文献
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Hiroyoshi Ohashi 《Curtis's Botanical Magazine》2016,33(3):192-200
Pseudotsuga japonica (Shiras.) Beissn. is described and illustrated. The species is endemic to Japan growing in limited areas in the southern central Honshu and eastern Shikoku. The history of its discovery, and present distribution and ecology are provided. 相似文献
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首次报道了华福花属华福花 Sinadoxa corydalifolia和东方五福花 Adoxa orientalis花部维管结构,并对五福花科3属4种植物的花部维管系统进行了比较研究。3属4种的花部维管系统表现出不同的对称性和不同的复化、减化以及不同的融合程度。基于花部维管系统的证据,本工作支持四福花属四福花 Tetradoxa omeiensis为科内原始类群代表的看法。 相似文献
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研究了36种中国产繁缕属(Stellaria)植物,根据模式材料或仅根据原描述,将已合格发表的1组、l系、12种、4变种和1变型首次归并到有关各类,依次列举人异名录中,其中有1移属。讨论了各种错误鉴定,同时对于选择性状、设想进化过程和分布记录均有讨论. 相似文献
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alpha-Amylase inhibitor from fungus Cladosporium herbarum F-828 总被引:1,自引:0,他引:1
N Saito 《The Journal of biological chemistry》1982,257(6):3120-3125
A strain of fungus Cladosporium herbarum extracellularly produced an inhibitor specific for mammalian alpha-amylase. The inhibitor was purified 81-fold by freeze-thawing, heat treatment, and column chromatography on DEAE-cellulose, Sephadex G-75, DEAE-Sephacel, and Bio-Gel P-100. An apparent molecular weight of approximately 18,000 was estimated for the inhibitor using Bio-Gel P-100 filtration. The purified inhibitor preparation was a glycoprotein containing about 10% carbohydrate. The amino acid analysis of the inhibitor showed abundances of Gly, Asp, Glu, Ser, Ala, and Thr residues. The inhibitor was stable between pH 5 and 12 at 4 degrees C, and below 80 degrees C at pH 7.0. A binary complex formation out of equimolar amounts of the inhibitor and alpha-amylase, was demonstrated by polyacrylamide gel electrophoresis, and Bio-Gel P-100 chromatography. Kinetic studies exhibited that the inhibitor noncompetitively inhibited the enzyme reaction with a Ki value of 2.3 approximately 4.8 x 10(-10) M, by combining with the enzyme molecule at a different site from the substrate binding site. 相似文献
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星花绣线菊中的一个新二萜——绣线菊内酯B 总被引:4,自引:1,他引:3
从星花绣线菊(Spiraeajaponicavar.stellaris)根中得到1个新的Atisine型二萜,命名为绣线菊内酯B(1)。通过光谱分析测定了其结构,此外还得到了9个已知化合物,包括1个atisine型二萜-spiraminol(2)和8个二萜生物碱,spiramineA,B,C,D,F,H,P,Q。 相似文献
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The development of the ultimobranchial gland (UBG) was studied from its earliest emergence in Rana japonica japonica. UBG primordia appear at stage 22 as outfoldings of the pharyngeal epithelium of the 6th visceral pouch in both sides of the body. At stage 24, they separate from the pharyngeal wall, and then become follicular at stage 25. During stages 27–30, which are just prior to metamorphic climax, the UBG seems to be activated, as shown by secondary follicle formation and pseudostratification of the follicle epithelium. At and after the completion of metamorphosis, the UBG shows a histological profile indicating low activity. 相似文献
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Olesen UH Christensen MK Björkling F Jäättelä M Jensen PB Sehested M Nielsen SJ 《Biochemical and biophysical research communications》2008,367(4):799-804
Malignant cells display increased demands for energy production and DNA repair. Nicotinamide adenine dinucleotide (NAD) is required for both processes and is also continuously degraded by cellular enzymes. Nicotinamide phosphoribosyltransferase (Nampt) is a crucial factor in the resynthesis of NAD, and thus in cancer cell survival. Here, we establish the cytotoxic mechanism of action of the small molecule inhibitor CHS-828 to result from impaired synthesis of NAD. Initially, we detected cross-resistance in cells between CHS-828 and a known inhibitor of Nampt, FK866, a compound of a structurally different class. We then showed that nicotinamide protects against CHS-828-mediated cytotoxicity. Finally, we observed that treatment with CHS-828 depletes cellular NAD levels in sensitive cancer cells. In conclusion, these results strongly suggest that, like FK866, CHS-828 kills cancer cells by depleting NAD. 相似文献
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粉花绣线菊复合群的化学分类研究 总被引:10,自引:1,他引:9
以粉花绣线菊复合群中二萜及二萜生物碱的结构特征,仿生合成及化学的相关性为基础,结合地理分布以及细胞学和形态学方面的研究资料,讨论粉花经菊复合群的化学分类,(1)具缩醛和二萜可能是绣线菊二萜生物碱的生源合成前体,(2)粉花绣线菊复合群是绣线菊属中特殊的,相对独立的类群;(3)我国西南尤其是横断山区是该复合群近代分化中心,有要能是起源中心;(4)对某些变种进行归并。 相似文献
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槐树组织细胞培养的研究 总被引:10,自引:0,他引:10
系统研究了槐树叶片、子叶及花药的培养方法和植株再生,获得了大量的试管苗,建立了槐树二倍体和单倍体植株快速繁殖的培养程序。实验表明在MS附加高浓度比值BA/IBA或2,4-D的培养基中可诱导各种外植体在短期内产生大量的不定芽和试管苗,但同时,又诱导产生了许多超度含水态苗。在培养过程中,BA浓度先高后低,既可获得大量的试管苗,又相对降低了超度含水态苗的比率,是槐树快速繁殖程序中的重要一环。组织学观察显示,槐树子叶切块培养中形成的胚状体来自于子叶的表皮及叶肉细胞,通过单细胞起源和多细胞出芽两种方式产生。 相似文献
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<正> 1993年作者在北京附近调查采集木腐菌时,发现其中7份标本具有明显的菌索和二系菌丝系统,其担孢子截形,并在Melzer试剂中呈黄褐色,经鉴定为日本多年卧孔菌Perenniporca japonica(Yasuda)T.Hattori & Ryvarden该种国内以前未见报道,现报道如下: 日本多年卧孔菌 图1 相似文献
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槐树子叶组织培养中的形态发生研究 总被引:1,自引:0,他引:1
槐树子叶在MS附加0.1~5 mg/L BA 和0.1—5 mg/L 2,4-D的培养丛上培养两周,获得了灰色疏松型及白、绿色紧密型两种类型的愈伤组织。后者经培养产生不定芽并再生植株。子叶切块在MS 附加0.1~8 mg/L 2,4-D等培养基上培养3周,在切口处形成愈伤组织的同时,由其表面直接分化产生胚状体。组织学观察表明,胚状体来源于子叶的表皮及叶肉细胞,胚状体产生通过单细胞起源及多细胞出芽两种方式发生。胚状体发育依次通过球形胚、心形胚、鱼雷形胚和子叶胚等阶段形成再生植株,其发育过程与合子胚相似。 相似文献
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Camellia japonica is a widespread and morphologically diverse tree native to parts of Japan and adjacent islands. Starch gel electrophoresis was used to score allelic variation at 20 loci in seeds collected from 60 populations distributed throughout the species range. In comparison with other plant species, the level of genetic diversity within C. japonica populations is very high: 66.2% of loci were polymorphic on average per population, with a mean number of 2.16 alleles per locus; the mean observed and panmictic heterozygosities were 0.230 and 0.265, respectively. Genotypic proportions at most loci in most populations fit Hardy-Weinberg expectations. However, small heterozygote deficiencies were commonly observed (mean population fixation index = 0.129). It is suggested that the most likely cause of the observed deficiencies is population subdivision into genetically divergent subpopulations. The overall level of population differentiation is greater than is typically observed in out-breeders: The mean genetic distance and identity (Nei's D and I) between pairs of populations were 0.073 and 0.930, respectively, and Wright's Fst was 0.144. Differences among populations appeared to be manifested as variation in gene frequencies at many loci rather than variation in allelic composition per se. However, the patterns of variation were not random. Reciprocal clinal variation of gene frequencies was observed for allele pairs at six loci. In addition, principal components analysis revealed that populations tended to genetically cluster into four regions representing the geographic areas Kyushu, Shikoku, western Honshu, and eastern Honshu. There was a significant relationship between genetic and geographic distance (r = 0.61; P < 0.01). Analysis of variance on allozyme frequencies showed that there was approximately four times as much differentiation among populations within regions, as among regions. It is likely that the observed patterns of population relationships result from the balance between genetic drift in small subpopulations and gene flow between them. 相似文献
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828 cases with multiple congenital contractures (arthrogryposis) were categorized and histories were reviewed to identify pregnancy complications. 53.0% of cases had a specified diagnosis or known cause and no diagnosis was found for 47.0% of which 27.2% were though to probably have a genetic basis and 19.8% were of unknown etiology. Our data provides no evidence to support the suggestion that arthrogryposis is frequently a result of environmental or structural causes including uterine structural anomaly, intra-uterine infection, etc. Normal frequencies of bleeding, hormone treatment during gestation, amniotic fluid leakage, uterine anomaly, maternal illness, and maternal and paternal age were noted. Apparent, increased frequencies of twinning, severe nausea, polyhydramnios and oligohydramnios were observed. In particular, the frequency of polyhydramnios was dramatically increased among lethal cases (vs survivors) and thus, polyhydramnios appears to be a poor prognostic sign when associated with decreased fetal movement. Large case control studies with complete pregnancy histories are needed to confirm these results and to definitively identify pregnancy complications that are useful "flags" to indicate decreased fetal movement in utero and thus, aid in the identification of primary causes of arthrogryposis. 相似文献
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白蔹单宁化学成分的研究 总被引:12,自引:0,他引:12
从白蔹Ampelopsis japonica(Thunmb.)Makino的乙酸乙酯提取物中分离出5个单宁化合物。经光谱分析和化学方法鉴定,它们为没食子酸(gallic acid,1),1,2,6-三氧-没食子酰基-β-D-吡喃葡萄糖(1,2,6-tri-O-galloy1-β-D-glucopyranoside,2),1,2,3,6-四氧-没食子酰基-β-D-吡喃葡萄糖(1,2,4,6-tetr 相似文献