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1.
粗糠树是紫草科厚壳村亚科厚壳树属植物,广布于我国长江以南及台湾,在西藏、青海、甘肃及陕西也有少量分布。学名通常采用E.dicksoniHance (1862),标式标本采自湖北。  相似文献   

2.
紫草科软紫草属(Arnebia Forsk.)植物约有22种,我国约产6种,其中软紫草(A. euchroma Johnst.),又名新疆紫草,是中药软紫草的主要原植物,黄花软紫草(A. guttata. Bunge),又名内蒙紫草,在内蒙古地区亦作紫草入药。在分类学上,软紫草属与紫草属(Lithospermum L.)“属间的界限不十分清楚,各家的认识不一致,种的划分也存在一些问题”,朱格麟对两个属的花、果特征进行了比较,认为两个属可以独立存在。据报道,紫草属植物的染  相似文献   

3.
消化系统肿瘤是威胁我国居民生命健康的重要杀手,其发病率和死亡率均占全部肿瘤的50%左右,研发高效安全的抗肿瘤药物是治疗消化系统肿瘤的基础。植物提取物是抗肿瘤药物的重要来源,紫草素(Shikonin)是一种存在于紫草科植物根茎中的药物成分,它对消化系统肿瘤细胞具有显著的杀伤效果。本文通过检索最近10年紫草素在消化系统肿瘤中发挥抗癌作用的相关文献,对紫草素及其衍生物在消化系统肿瘤中的抗癌机制进行系统归纳整理,并分析了今后紫草素应用于临床治疗消化系统肿瘤的研究方向,为进一步探索紫草素在消化系统肿瘤中的抗癌机制研究和新药研发提供理论依据。  相似文献   

4.
滇紫草愈伤组织培养的初步研究   总被引:5,自引:2,他引:3  
滇紫草(Onosma paniculatum)属紫草科滇紫草属植物,其根部皮层富含的紫草素(α—萘醌系列衍生物),可用作治疗外伤与痔疮的药物或高级染料以及化妆品。滇紫草为云南特有,由于人工栽培困难,加之不断采挖,致使这一资源受到严重的破坏,产品供不应求。日本Tabata等对紫草(Lithospermum erythrorhizon)的组织培养进行了一系列的研究,但对滇紫草组织培养以生产紫草素的研究至今未见报道。基于这一现状,我们从1988年开始着手进行滇紫草组织培养的研究,以探讨应用组织培养技术生产紫草素的可能性。  相似文献   

5.
倒提壶     
倒提壶(Cynoglossum amabile Stapf et Drumm.)为紫草科(Boraginaceae)琉璃草属(Cynoglossum)植物,主要分布于我国云南、贵州西部、西藏西南部至东南部、四川西部及甘肃南部.多年生草本,高15~60 cm.茎单一或数条丛生,密生贴伏短柔毛.花序锐角分枝,分枝紧密,向上...  相似文献   

6.
黄土高原紫草科植物   总被引:2,自引:0,他引:2  
报道了黄土高原紫草科植物23属51种7变种的名称,分布,生境和用途。  相似文献   

7.
紫草宁(Shikonin)系紫草(Lithospermum erytrorihizon Sieb et Zuce)等部分紫草科植物根中所含的α-萘醌系列的化合物(图1),用作治疗外伤与痔疮的药物或高级染料。田端等从紫草的幼苗诱发愈伤组织,用琼脂  相似文献   

8.
前言     
《广西植物》2021,(S01):F0002-F0002
中国科学院院士王文采,是我国著名的植物分类学家,长期从事有花植物分类学研究。王文采院士在毛茛科(Ranunculaceae)、苦苣苔科(Gesneriaceae)、紫草科(Boraginaceae)、荨麻科(Urticaceae)等植物系统分类学研究中倾注了大量心血,修订了毛茛科翠雀花属(Delphinium)、唐松草属(Thalictrum)、铁线莲属(Clematis)等多个属的分类系统。2019年6月,王文采院士开始对中国银莲花属(Anemone)进行分类学修订,并于2020年7月完成了《中国银莲花属新分类》的整个编写工作。  相似文献   

9.
正王文采院士是著名的传统植物分类学家。他主要研究毛茛科、苦苣苔科、紫草科、荨麻科等的分类和系统学,新发现了20个属,约500个新种,修订了毛茛科翠雀属、唐松草属、铁线莲属等多个属的分类系统;同时在对苦苣苔科的分类和系统学研究中,揭示了科的演化趋势,建立了后蕊苣苔属、吊石苣苔属和小花苣苔属的分类系统。我和他的相知相识就缘自"植物分类"这个专业媒介。事情可以追溯到1961年,那  相似文献   

10.
聚合草(Symphytum Pergrinum)又名紫草根,属紫草科多年生草本植物,为优良的饲料植物。我国于1964年及1971—72年间曾先后由日本、澳大利亚和朝鲜引入。该植物的肉质根具有强烈的再生能力,通常可用以进行切根繁殖,结合器官分化的研究,1977年底到1978年初曾用聚合草的肉质根切段,进行了组织培养试验。虽然在一些植物  相似文献   

11.
Leccinum scabrum sporocarps and associated topsoils from two areas in Poland have been characterized for contents and bioconcentration potential of Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn. Topsoil and fruitbody element composition varied between the two study sites, most likely as a result of local soil geochemistry. Element content of the labile fraction in topsoil from both sites followed the ‘pseudo‐total’ fraction and median values (mg kg?1 dry matter) were: K 380 and 340, Mg 760 and 840, P 1100 and 920, Al 3800 and 8100, Ag 0.31 and 0.28, Ba 28 and 37, Ca 920 and 790, Cd 0.23 and 0.23, Co 2.0 and 1.7, Cu 3.2 and 3.6, Fe 2800 and 6300, Mn 280 and 180, Na 99 and 110, Ni 7.8 and 8.8, Pb 12 and 18, Rb 1.3 and 2.1, Sr 4.8 and 4.0 and Zn 22 and 19, respectively. Only for some elements such as K, Mg, Al, Ag, Ca, Co, Mn, Na, Ni, Sr and Zn we found concentration differences between the two study sites for the caps of sporocarps. With the exception of Al, Mn, Na and Pb, stipes showed a similar tendency. Caps had a higher concentration of K, Rb, P, Mg, Al, Ag, Cu, Fe, Zn, Cd, Pb and Ni compared to stipes, while Na, Ba and Sr contents were higher in stipes. The comparison of soil and fruitbody concentrations indicates that L. scabrum bioconcentrate some elements while others are bioexcluded.  相似文献   

12.
The Hierarchical Taxonomy of Psychopathology (HiTOP) is a scientific effort to address shortcomings of traditional mental disorder diagnoses, which suffer from arbitrary boundaries between psychopathology and normality, frequent disorder co‐occurrence, heterogeneity within disorders, and diagnostic instability. This paper synthesizes evidence on the validity and utility of the thought disorder and detachment spectra of HiTOP. These spectra are composed of symptoms and maladaptive traits currently subsumed within schizophrenia, other psychotic disorders, and schizotypal, paranoid and schizoid personality disorders. Thought disorder ranges from normal reality testing, to maladaptive trait psychoticism, to hallucinations and delusions. Detachment ranges from introversion, to maladaptive detachment, to blunted affect and avolition. Extensive evidence supports the validity of thought disorder and detachment spectra, as each spectrum reflects common genetics, environmental risk factors, childhood antecedents, cognitive abnormalities, neural alterations, biomarkers, and treatment response. Some of these characteristics are specific to one spectrum and others are shared, suggesting the existence of an overarching psychosis superspectrum. Further research is needed to extend this model, such as clarifying whether mania and dissociation belong to thought disorder, and explicating processes that drive development of the spectra and their subdimensions. Compared to traditional diagnoses, the thought disorder and detachment spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and higher acceptability to clinicians. Validated measures are available to implement the system in practice. The more informative, reliable and valid characterization of psychosis‐related psychopathology offered by HiTOP can make diagnosis more useful for research and clinical care.  相似文献   

13.
Polyamines are fundamental molecules of life, and their deep evolutionary history is reflected in extensive biosynthetic diversification. The polyamines putrescine, agmatine, and cadaverine are produced by pyridoxal 5′-phosphate-dependent L-ornithine, L-arginine, and L-lysine decarboxylases (ODC, ADC, LDC), respectively, from both the alanine racemase (AR) and aspartate aminotransferase (AAT) folds. Two homologous forms of AAT-fold decarboxylase are present in bacteria: an ancestral form and a derived, acid-inducible extended form containing an N-terminal fusion to the receiver-like domain of a bacterial response regulator. Only ADC was known from the ancestral form and limited to the Firmicutes phylum, whereas extended forms of ADC, ODC, and LDC are present in Proteobacteria and Firmicutes. Here, we report the discovery of ancestral form ODC, LDC, and bifunctional O/LDC and extend the phylogenetic diversity of functionally characterized ancestral ADC, ODC, and LDC to include phyla Fusobacteria, Caldiserica, Nitrospirae, and Euryarchaeota. Using purified recombinant enzymes, we show that these ancestral forms have a nascent ability to decarboxylate kinetically less preferred amino acid substrates with low efficiency, and that product inhibition primarily affects preferred substrates. We also note a correlation between the presence of ancestral ODC and ornithine/arginine auxotrophy and link this with a known symbiotic dependence on exogenous ornithine produced by species using the arginine deiminase system. Finally, we show that ADC, ODC, and LDC activities emerged independently, in parallel, in the homologous AAT-fold ancestral and extended forms. The emergence of the same ODC, ADC, and LDC activities in the nonhomologous AR-fold suggests that polyamine biosynthesis may be inevitable.  相似文献   

14.
Tentacles are remarkable anatomical structures in invertebrates for their diversity of form and function. In bivalves, tentacular organs are commonly associated with protective, secretory, and sensory roles. However, anatomical details are available for only a few species, rendering the diversity and evolution of bivalve tentacles still obscure. In Pteriomorphia, a clade including oysters, scallops, pearl oysters, and relatives, tentacles are abundant and diverse. We investigated tentacle anatomy in the group to understand variation, infer functions, and investigate patterns in tentacle diversity. Six species from four pteriomorphian families (Ostreidae, Pinnidae, Pteriidae, and Spondylidae) were collected and thoroughly investigated with integrative microscopy techniques, including histology, scanning electron microscopy, and confocal microscopy. Tentacles can be classified as middle fold tentacles (MFT) and inner fold tentacles (IFT) according to their position with respect to the folds of the mantle margin. While MFT morphology indicates intense secretion of mucosubstances, no evidence for secretory activity was found for IFT. However, both tentacle types have appropriate ciliary distribution and length to promote mucus transportation for cleaning and lubrication. Protective and sensory functions are discussed based on different lines of evidence, including secretion, cilia distribution, musculature, and innervation. Our results support the homology of MFT and IFT only for Pterioidea and Ostreoidea, considering their morphology, the presence of ciliated receptors at the tips, and branched innervation pattern. This is in accordance with recent phylogenetic hypotheses that support the close relationship between these superfamilies. In contrast, major structural differences indicate that MFT and IFT are probably not homologous across all pteriomorphians. By applying integrative microscopy, we were able to reveal anatomical elements that are essential for the understanding of homology and function when dealing with such superficially similar structures.  相似文献   

15.
Athyrisinine brachiopods from the Upper Silurian of Russia and the Lower–Middle Devonian of China and north Vietnam include over 70 species belonging to Athyrisina and Parathyrisina ; generic and subfamilial diagnoses are emended. Five genera are considered synonyms of Athyrisina and three of Parathyrisina . A neotype is selected and illustrated for Athyrisina squamosa , the type species of Athyrisina . Four nomina nova , Athyrisina xui , Parathyrisina wani , P. minima , and P. cheni , are suggested as new substitute names for Athyrisina tumida Wang, in Xu et al. 1978 (primary homonymy), Athyrisinoides ganxiensis Wan, in Xu et al. 1978, Parathyrisina minor Zhang, in Zhang and Fu 1983, and Athyrisinoides tudilingensis Chen, 1979 (secondary homonyms) respectively. A new genus, Bruntosina , is described from the Emsian to Eifelian of the Qinling region. A new subfamily, Homeathyridinae, is erected within the Athyrididae with Homeathyris , Pseudohomeospira , and Squamathyris included, revised and their diagnoses emended. Homeathyris incisus sp. nov. is described from the Ludfordian of Novaya Zemlya. Ikella is revised and excluded from the athyrisinins. The origin and dispersal of the homeathyridins and the athyrisinins are discussed.  相似文献   

16.
Regulation of angiogenesis by nitric oxide (NO) is controversial since NO has been shown to have both pro- and anti-angiogenic effects. In this study, we examined the effect of the NO donor, S-nitro-N-acetyl-penicillamine (SNAP), on in vitro angiogenesis, and the mechanisms involved: PKC activity, ERK and c-Jun phosphorylation, and AP-1 DNA binding activity, in microvascular endothelial cells. SNAP, at 0.5-4 mM, significantly and dose-dependently inhibited angiogenesis, PKC activity, and ERK and c-Jun phosphorylation up to 80%, 83%, and 63% and 73%, respectively. SNAP at concentrations > 2mM also abolished AP-1 binding activity. Lower concentrations of SNAP (0.1-0.3 mM) significantly increased angiogenesis, PKC activity, and ERK and c-Jun phosphorylation up to 46%, 60%, and 61% and 180%, respectively. These findings indicate that the dual pro- and anti-angiogenic actions of NO are dose-dependent and suggest that they are mediated by PKC and ERK acting on AP-1.  相似文献   

17.
自然保护区生态旅游对野生动物的影响   总被引:17,自引:2,他引:15  
马建章  程鲲 《生态学报》2008,28(6):2818-2818~2827
目前中国的很多自然保护区开展了生态旅游,但这类活动对野生动物的影响研究却十分薄弱,因此十分有必要在介绍欧美、澳洲学者的研究进展基础上,针对我国的研究现状,提出该领域的研究方向、监测和管理策略.自然保护区的生态旅游活动主要有野生动物观赏、徒步行走、摄影、野外宿营、山地车或雪地车、电动或机动艇游湖、溪涧漂流、环境教育、社区访问等,旅游活动类型、范围、强度、时空分布等是影响对野生动物干扰大小的主要因素.生态旅游对野生动物的影响包括直接影响(个体的行为反应和生理指标改变、繁殖力降低、种群分布和物种组成的改变等)和间接影响(生境破坏、外来种散布和环境污染等).国外生态旅游对鸟类的影响研究较多,主要集中鸟类的惊飞反应、取食、能量消耗、繁殖等方面;对兽类影响的研究主要集中在行为、生理指标改变、种群数量等方面.我国未来的研究应注重收集基础性研究数据和深入探讨一些理论与应用问题,要运用多种技术手段对自然保护区野生动物的行为、生理、种群动态、物种多样性、生境质量、游客的时空分布、态度和行为等进行长期监测,而后将其结果应用到野生动物、生境以及游客的管理决策中去.另外,研究中应重视自然科学和社会科学的多学科交叉融合.  相似文献   

18.
Olson, G. A., R. D. Olson and A. J. Kastin. Endogenous opiates: 1996. Peptides 18(10) 1651–1688, 1997.—This paper is the nineteenth installment of our annual review of research concerning the opiate system. It summarizes papers published during 1996 reporting the behavioral effects of the opiate peptides and antagonists, excluding the purely analgesic effects, although stress-induced analgesia is included. The specific topics covered this year include stress, tolerance and dependence; eating; drinking; gastrointestinal, renal, and hepatic function; mental illness and mood; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurological disorders; electrical-related activity; general activity and locomotion; sex, pregnancy, and development; immunological responses; and other behaviors.  相似文献   

19.
Twenty carbohydrates (C), 18 nitrogen compounds (N), and 9 vitamins were examined for their effects on the growth and conidiation of the nematode-egg-parasitic fungi Arkansas Fungus 18 (ARF18, isolate 908) and Pochonia chlamydospora var. chlamydospora in solid and liquid cultures. Glycogen was the best, and inulin, D-(+)-galactose, and soluble starch were good C sources for the growth of ARF18 in both solid and liquid cultures. ARF18 could not utilize alpha-cellulose in liquid; alpha-lactose and D-mannitol in solid; and D-(+)-xylose, L-(-)-sorbose, and D-(-)-ribose in both solid and liquid cultures. Casein was the best N source for ARF18 growth in both solid and liquid cultures and L-aspartic acid, DL-glutamic acid, peptone, and L-histidine were good in solid culture. ARF18 could not utilize L-cystine and L-tyrosine in solid culture, and L-cystine, DL-methionine, peptone, L-proline, and ammonium nitrate in liquid culture. Supplement of vitamins appeared to be unnecessary for ARF18 to grow. For P. chlamydospora var. chlamydospora growth, all test C sources, except L-(-)-sorbose, alpha-cellulose, citric acid, and D-(+)-glucose, were good in both solid and liquid cultures. Most N compounds were good for P. chlamydospora var. chlamydospora growth with casein and peptone the best. Vitamins had limited effect on P. chlamydospora var. chlamydospora growth. P. chlamydospora var. chlamydospora conidiation was well supported by D-(-)-ribose, D-(-)-fructose, melibiose, and D-(+)-galactose as C sources and by L-aspartic acid, DL-glutamic acid, and L-arginine as N sources. Excluding myo-inositol from the medium containing all other test vitamins increased P. chlamydospora var. chlamydospora conidiation, while excluding pyridoxine appeared to reduce its conidiation.  相似文献   

20.
贵州罗甸纳水上石炭统(宾夕法尼亚亚系)地层的再研究   总被引:5,自引:0,他引:5  
本文详细描述了贵州罗甸纳水上石炭统(宾夕法尼亚亚系)剖面的生物地层和年代地层,其牙形刺序列自上而下可详细划分为:Streptognathodus isolatus, S. wabaunsensis, S. tenuialveus, S. firmus, Idiognathodus nashuiensis , Streptognathodus simulator, S. guizhouensis , S. gracilis-S, excelsus , S. cancellosus , S. clavatulus , S. nodocarinatus , Idiognathodus podolskensis , Mesogondolella clarki -Idiognathodus robustus , Diplognathodus ophanus-D, ellesmerensis, Idiognathoides ouachitensis, Streptognathodus expansus, Idiognathoides sulcatus parva, Idiognathodus primulus-Neognathodus bassleri, Idiognathodus primulus-Neognathodus symmetricus, Neognathodus symmetricus, Idiognathoides corrugatus-I, pacificus, I. sinuatus, I. sulcatus sulcatus, Declinognathodus noduli ferus 和 Gnathodus bilineatus bollandensis 等带。 Declinognathodus noduliferus 和 Streptognathodus isolatus 的首次出现分别代表上石炭统(宾夕法尼亚亚系)和二叠系的开始。根据牙形刺和有孔虫的序列,罗甸纳水剖面的上石炭统(宾夕法尼亚亚系)地层自下而上可划分为罗苏阶(Luosuan)、滑石板阶(Huashibanian)、达拉阶(Dalaan)和马平阶(Mapingian),并可与俄罗斯的巴什基尔阶(Bashkirian)、莫斯科阶(Moscovian)、卡西莫夫阶(Kasimovian)和格舍尔阶(Gzhelian),北美的莫罗阶(Morrowan)、阿托克阶(Atokan)、得梅因阶(Desmoinesian)、密苏里阶(Missourian)和弗吉尔阶(Virgilian)进行对比。另外,本文也详细讨论了剖面中的石炭系中间界线及石炭-二叠系界线。  相似文献   

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