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1.
Our recent molecular phylogenetic study revealed a previously unrecognized clade of six species that is sister to Elaphoglossum. Within this clade, four species are currently classified in Bolbitis, one in Lomagramma, and one in Acrostichum. For this clade, we propose the name Mickelia, with M. nicotianifolia as the type species. We also make new combinations for the species in our phylogenetic study shown to belong to Mickelia ( M. bernoullii, M. guianensis, M. hemiotis, M. nicotianifolia, M. oligarchica, and M. scandens) and two other species believed to belong to the clade based on morphology ( M. lindigii, M. pergamentacea). A new hybrid and two new species are also described ( M. ×atrans, M. furcata, and M. pradoi). In total, Mickelia consists of ten species and one hybrid. It is entirely neotropical. We provide a key to the genera of bolbitidoid ferns and
a synopsis of Mickelia that gives for each species a complete synonymy, geographical distribution, comparative discussion, and illustration. 相似文献
3.
【背景】作为临床最常见的非结核条件致病分枝杆菌,脓肿分枝杆菌( Mycobacteroides abscessus)因其天然、多耐药等特性成为目前临床治疗的一大挑战。作为分枝杆菌限制性营养元素——铁摄取的关键系统,分枝杆菌素(mycobactin,MBT)、羧基分枝杆菌素(carboxymycobactin,cMBT)与病原分枝杆菌的毒力、耐药等密切相关。【目的】丰富分枝杆菌MBT、cMBT结构数据,探究MBT在致病分枝杆菌起源过程中的演化规律。【方法】在MALDI-TOF-MS与FT-MS/MS解析脓肿MBT、cMBT结构的基础上,进一步开展其活性分析与生物合成基因簇比较基因组分析。【结果】虽然脓肿分枝杆菌MBT、cMBT母核修饰模式与海洋分枝杆菌最相似,R1、R2、R3、R5等位置的修饰完全相同,而且脂肪酸链均位于R4位置;但脂肪酸链长度不同[C10-17 (MBT)、C4-8 (cMBT)],为新结构。Fe-cMBT不仅以浓度依赖方式促进脓肿分枝杆菌生长,而且利用效率显著高于FeCl 3,相关结果表明MBT-cMBT是脓肿分枝杆菌高效获取铁元素的关键系统。与MBT结构结果一致, mbt-1基因簇共线性分析及 mbt-1、 mbt-2系统发育分析结果均表明脓肿分枝杆菌与海洋分枝杆菌( M. marinum)亲缘关系最近,而非结核分枝杆菌( M. tuberculosis)或耻垢分枝杆菌( M. smegmatis) (基于16S rRNA基因序列分析)。进一步分析发现, M. marinum、 M. tuberculosis、 M. bovis等病原分枝杆菌脂肪酸链长度变化范围仅4 C,而 M. abscessus、 M. fortuitum、 M. avium和 M. smegmatis等条件致病与非致病菌的脂肪酸链长度变化范围为7-11 C,暗示MBT同系物脂肪酸链长度变化范围与分枝杆菌不同生活方式、环境之间可能存在关联。【结论】作为获取铁元素的关键系统,具有独特结构的脓肿分枝杆菌MBT-cMBT在致病、耐药等方面的作用及起源、演化规律值得深入研究。 相似文献
4.
As a result of a recent alpha-taxonomic study of the genus Magnolia s. str. in Mexico and Central America, four new species and four new subspecies of Magnolia sect. Theorhodon are proposed, including M. iltisiana, M. panamensis, M. tamaulipana, M. sororum subsp. lutea, and M. pacifica, consisting of three subspecies: pacifica, pugana, and tarahumara. Additionally, a new combination, M. guatemalensis subsp. hondurensis, is made, and a new section, M. sect. Splendentes, is erected for the Caribbean species. The results have implications for understanding Magnolia biogeography, and M. tamaulipana has potential for horticulture in temperate zones. Keys to genera, sections, and species, and maps of species distributions
are presented. Magnolia grandiflora L. and M. schiedeana Schltdl. are lectotypified.
Como resultado de un estudio alfa-taxonómico reciente del género Magnolia s. str. en México y Centro América, se proponen cuatro especies nuevas y cuatro subespecies nuevas de Magnolia sect. Theorhodon, incluyendo M. iltisiana, M. panamensis, M. tamaulipana, M. sororum subsp. lutea y. M. pacifica, la última consiste de tres subespecies: pacifica, pugana y tarahumara. Adicionalmente, se hace la combinación M. guatemalensis subsp. hondurensis y se erige M. sect. Splendentes para las especies del Caribe. Los hallazgos tienen implicaciones en el entendimiento de la biogeografia de Magnolia y. M. tamaulipana tiene potencial en la horticultura de zonas templadas. Se presentan claves para géneros, secciones y especies, y mapas de
distribución para las especies. Magnolia grandiflora L. y M. schiedeana Schltdl. son lectotipificadas. 相似文献
5.
Figure 2a–r of the above article is reprinted here at the request of the author because the print quality was not up to standard in the
issue.
Fig. 2a–r. Localization of 28S rDNA ( white arrowheads) by fluorescence in situ hybridization of preparations from various Myrmecia species with different chromosome numbers. a–d, i–m Hybridized in situ and propidium iodide-stained chromosomes. e–h, n–r 4’,6-diamidino-2-phenylindole-stained chromosomes. a, e
M. croslandi (2 n=4). b, f
M. pilosula (2 n=22); the inset in b shows repeated layers of rDNA-positive signals in C-band. c, g
M. pilosula (2 n=23). d, h
M. gulosa (2 n=38). i, n
M. forficata (2 n=52). j, o
M. mandibularis (2 n=56). k, p
Myrmecia sp. cf. M. arnoldi (2 n=60) i, q
M. occidentalis (2 n=64) m, r
M. simillima (2 n=70). Bars represent 10 μm. The long bar in h applies also to d; the short bar in r to all other panels
Chromosoma (1996) 105:190–196
Received: 22 March 1996; in revised form: 3 June 1996 / Accepted: 4 June 1996 相似文献
6.
Abstract The Old World syrphid genus Merodon Meigen 1803 is highly species-diverse and has a significant number of endemic species in the circum-Mediterranean area. The present study reports on taxonomic changes resulting from the examination of adult Merodon specimens collected in 15 Turkish provinces during the period 1992 to 2002, and provides new faunistic data. Merodon ilgazense n. sp. is described. Four species of Merodon new to Turkey are recorded: M. armipes Rondani 1843, M. auronites Hurkmans 1993, M. bessarabicus Paramonov 1924 and M. chalybeatus Sack 1913. Lectotypes are designated for two taxa: M. chalybeatus Sack 1913 and M. clunipes Sack 1913. Merodon italicus Rondani 1845 rev. stat. is reinstated as a valid species. Following a detailed study of the type material in different entomological collections, the status of 10 taxa is revised and five new synonymies are proposed: M. albonigrum Vuji Radenkovi &; S?imi 1996 n. syn. (=junior synonym of M. chalybeatus Sack 1913); M. alexeji Paramonov 1925 n. syn. (=junior synonym of M. serrulatus Wiedemann in Meigen 1822); M. aureotibia Hurkmans 1993 n. syn. (=junior synonym of M. vandergooti Hurkmans 1993); M. kaloceros Hurkmans 1993 n. syn. (=junior synonym of M. erivanicus Paramonov 1925); M. longicornis Sack 1913 n. syn. (=junior synonym of M. italicus Rondani 1845). 相似文献
7.
Four new species are described and discussed: from Bolivia M. (sect. Habbasia ser. Setosae) huanchacae; from SE brazil M. (sect. Habbasia ser. Pachycarpae) chiliomera and M. (sect. Mimosa) murex; and from Ecuador M. (sect. Mimosa subser. Polycarpae) Loxensis. The two Brazilian species are illustrated. 相似文献
8.
The western Palaearctic species of the genus Mesoleptus Gravenhorst 1829 are redescribed and keys are given for their identification. Also a key for the identification of the three stilpnine genera ( Atractodes, Mesoleptus, and Stilpnus) is given and the biology of the genus is discussed shortly. The following species are described as new: Mesoleptus hispanicus n. sp., M. sawoniewiczi n. sp. and M. tunisiensis n. sp. The male of Mesoleptus tobiasi Jonaitis is described for the first time. New combinations is M. incessor (Haliday). New synonyms number 143 and 34 lectotypes are chosen. 相似文献
9.
【背景】薇甘菊是入侵性和危害性极强的外来入侵植物,对生物多样性和农林业生产造成严重影响。观测薇甘菊新枝的月生长动态,了解薇甘菊快速生长扩散的原因,能够为薇甘菊的合理防治提供参考。【方法】采用定点定时观测法,历时2年对海南7个市县薇甘菊新枝的月生长量进行测定。【结果】薇甘菊在海南全年可生长,一新枝月平均生长66 cm,全年累计平均生长795 cm。薇甘菊生长高峰期在6月和8月,其中6月平均生长120 cm,8月平均生长106 cm。薇甘菊最小生长量在1月和12月,平均生长量均为21 cm。薇甘菊在6—10月生长较快,一新枝累计平均生长489 cm,占全年生长量的61.5%;在4—5月和11月生长次之,一新枝累计平均生长196 cm,占全年生长量的24.7%;在1—3月和12月生长缓慢,一新枝累计平均生长110 cm,占全年生长量的13.8%。薇甘菊的花果期在10月至次年3月,一些种群在1—3月再次开花或在3—5月开花。薇甘菊的生长量与温度呈极显著正相关,相关系数为0.91;与降雨量呈显著正相关,相关系数0.56。【结论与意义】薇甘菊是多分枝植物,一新枝年生长量可达795 cm,能迅速生长形成种群。温度是薇甘菊生长的主要因素,降雨在一定程度促进了薇甘菊的生长。 相似文献
10.
The genus Meira Jacquelin du Val 1852 is revised, four lectotypes and a neotype are designated, a new synonymy is proposed and four new species from France – one from Alpes-Maritimes ( Meira alpina n. sp.), two from Var ( M. echinoides n. sp. and M. teloniensis n. sp.), one from Vaucluse ( M. germanni n. sp.) and one from Italy, from Abruzzo ( M. osellai n. sp.) are described,. Synonyms, bibliographic and ecological data are provided. Whole-body photos of the types of the old species and of the four new species, drawings of systematically important characters, keys and distribution maps are also presented. 相似文献
11.
A new series of pyrazolo[3,4-d]pyrimidine-6-one derivatives ( 2a–2j) were prepared by using the Biginelli multicomponent cyclocondensation of 3-methyl-1-phenyl-1 H-pyrazol-5(4 H)-one ( 1a), different aromatic aldehydes, and urea with a catalytic amount of HCl at reflux temperature. These compounds were characterized by IR, 1H NMR, 13C NMR, and Mass spectral data. In vitro antiamoebic activity was performed against HM1:IMSS strain of Entamoeba histolytica. The results showed that the compounds 2b, 2i, and 2j with IC 50 values of 0.37 µM, 0.04 µM, and 0.06 µM, respectively, exhibited better antiamoebic activity than the standard drug metronidazole (IC 50?=?1.33 µM). The toxicological studies of these compounds on human breast cancer MCF-7 cell line showed that the compounds 2b, 2i, and 2j exhibited >80% viability at the concentration range of 1.56–50 µM. 相似文献
12.
On the basis of Rosen's representation of ( M, R)-systems as sequential machines (Rosen, Bull. Math. Biophys., 26, 103–111, 1964), the existence of projective limits in categories of general ( M, R)-systems is proved. 相似文献
13.
【目的】研究乙酰化修饰对Ku蛋白活性的影响。【方法】利用耻垢分枝杆菌为表达菌株,转入Ku蛋白表达质粒,纯化具有乙酰化修饰的Ku蛋白和无乙酰化的Ku蛋白突变体,比较两类蛋白的生化活性;分析氧化压力和酸性环境下耻垢分枝杆菌细胞内Ku蛋白乙酰化水平的变化。【结果】Ku蛋白过量表达的耻垢分枝杆菌比转入空质粒的对照菌株生长缓慢;乙酰化Ku蛋白比未发生乙酰化Ku蛋白修复断裂DNA的活性降低、DNA结合活性降低;氧化压力和酸性压力环境下,耻垢分枝杆菌细胞内Ku蛋白数量降低,乙酰化Ku蛋白数量变化不大。【结论】乙酰化修饰能够调节Ku蛋白的DNA结合活性,从而调节非同源末端连接修复系统的活性;Ku蛋白乙酰化程度升高是耻垢分枝杆菌对不良生长环境的反应。 相似文献
14.
Glutathione transferase P1-1 is over expressed in some cancer cells and contributes to detoxification of anticancer drugs, leading to drug-resistant tumors. The inhibition of human recombinant GSTP1-1 by natural plant products was investigated using 10 compounds isolated from plants indigenous to Southern and Central Africa. Monochlorobimane and 1-chloro-2,4-dinitrobenzene were used to determine GST activity. Each test compound was screened at 33 and 100 µM. Isofuranonapthoquinone ( 1) (from Bulbine frutescens) showed 68% inhibition at 33 µM, and sesquiterpene lactone ( 2) (from Dicoma anomala) showed 75% inhibition at 33 μM. The IC 50 value of 1 was 6.8 μM. The mode of inhibition was mixed, partial (G site) and noncompetitive (H site) with K i values of 8.8 and 0.21 µM, respectively. Sesquiterpene 2 did not inhibit the CDNB reaction. Therefore, isofuranonapthoquinone 1 needs further investigations in vivo because of its potent inhibition of GSTP1-1 in vitro. 相似文献
15.
Three new species of Malouetia (Apocynaceae) are described and illustrated: M. amazonica and M. pumila from Brazil and M. gentryi from Peru. Malouetia amazonica grows in inundated igapó forest, whereas the other two are found in non-inundated habitats: M. pumila in campa fechada, and M. gentryi in upland forest. 相似文献
16.
【背景】利迪链霉菌( Streptomyces lydicus)对多种作物均有较好的促生效果,且对病原真菌具有广谱抑制作用,但该菌对细菌性青枯病的防控研究较少。【目的】探究利迪链霉菌M01能否促进番茄生长并抑制番茄青枯病,以及M01对番茄生长的影响是否通过影响根际细菌群落结构实现。【方法】采用温室盆栽试验和扩增子高通量测序技术研究M01对番茄生长、青枯病发病率及根际细菌群落组成的影响。【结果】施用利迪链霉菌M01的番茄植株鲜重、干重、株高、用土壤与作物分析开发(soil and plant analyzer develotrnent, SPAD)方法测量的叶绿素浓度、根系活力和植株P含量比对照分别提高了22.7%、12.5%、16.0%、28.1%、18.4%和17.9%,其中对株高、SPAD值和植株磷含量影响显著( P<0.05)。M01处理延缓了番茄青枯病的发病时间,接种9周后发病率比对照降低了41.8%。此外,M01对番茄根际细菌群落无显著影响(门水平群落组成, P=0.4;属水平群落组成, P=0.4)。【结论】利迪链霉菌M01可促进番茄植株生长并抑制番茄青枯病,利迪链霉菌M01对番茄生长的影响并非通过调控根际细菌群落实现。 相似文献
17.
Seven new species of Mascagnia are described: M. tomentosa from southern Mexico and Central America; M. arenicola from the Guianas; M. riparia, M. tucuruensis, and M. velutina from Brazil; M. boliviana from Bolivia; and M. australis from Argentina and Paraguay. These novelties were previously included in the “ M. sepium-complex,” an omniumgatherum comprising superficially similar yellow-flowered taxa. 相似文献
18.
A series of novel, potent and selective muscarinic receptor 1 agonists (M1 receptor agonists) that employ a key N-substituted morpholine arecoline moiety has been synthesized as part of research effort for the therapy of Alzheimer’s diseases.
The ester group of arecoline (which is reported as mucarinic agonist) has been replaced by N-substituted morpholine ring. The structure activity relationship reveals that the increase in lipophilic carbon chain on the
nitrogen atom of the morpholine ring increases the affinity of M1 receptor. In the present study, we are reporting N-amino acid substituted 9( a– k) and dipeptides substituted 10( a– j) and 11( a– j) morpholino arecoline derivatives, along with their in vitro muscarinic binding studies by using [ 3H]QNB and also in vivo evaluation of memory and learning in male Wistar rats (passive avoidance test plus maze studies) as
M1 receptor agonist. Some molecules from the dipeptide series ( 10b, 10c and 10j) showed potent M1 receptor agonist activity. Other derivatives also showed considerable M1 receptor binding affinity. 相似文献
19.
BackgroundThe predatory mirids of the genus Macrolophus are key natural enemies of various economically important agricultural pests. Both M. caliginosus and M. pygmaeus are commercially available for the augmentative biological control of arthropod pests in European greenhouses. The latter species is known to be infected with Wolbachia -inducing cytoplasmic incompatibility in its host- but the presence of other endosymbionts has not been demonstrated. In the present study, the microbial diversity was examined in various populations of M. caliginosus and M. pygmaeus by 16S rRNA sequencing and denaturing gradient gel electrophoresis. ResultsBesides Wolbachia, a co-infection of 2 Rickettsia species was detected in all M. pygmaeus populations. Based on a concatenated alignment of the 16S rRNA gene, the gltA gene and the coxA gene, the first is phylogenetically related to Rickettsia bellii, whereas the other is closely related to Rickettsia limoniae. All M. caliginosus populations were infected with the same Wolbachia and limoniae-like Rickettsia strain as M. pygmaeus, but did not harbour the bellii-like Rickettsia strain. Interestingly, individuals with a single infection were not found. A PCR assay on the ovaries of M. pygmaeus and M. caliginosus indicated that all endosymbionts are vertically transmitted. The presence of Wolbachia and Rickettsia in oocytes was confirmed by a fluorescence in situ hybridisation. A bio-assay comparing an infected and an uninfected M. pygmaeus population suggested that the endosymbionts had minor effects on nymphal development of their insect host and did not influence its fecundity. ConclusionTwo species of the palaearctic mirid genus Macrolophus are infected with multiple endosymbionts, including Wolbachia and Rickettsia. Independent of the origin, all tested populations of both M. pygmaeus and M. caliginosus were infected with three and two endosymbionts, respectively. There was no indication that infection with endosymbiotic bacteria had a fitness cost in terms of development and fecundity of the predators. 相似文献
20.
Bees comprise a monophyletic group of seven families with more than 16000 described species worldwide. Convincing new phylogenetic hypotheses suggest that one of the smallest families, the Melittidae, could be the basal group of the bee clade. Among the 14 melittid genera, the genus Melitta Kirby 1802, is the most widespread and one of the most diverse. Most revisionary studies of Melitta were confined to limited geographical areas. An overview of the literature and the examination of 7817 specimens from various collections, including type material, have enabled the first monographic revision of the genus Melitta. This revision includes a cladistic analysis, comprehensive catalogue and identification key. We provide diagnoses, global distributions, phenology and host plants for the 43 known species (including 2 new ones). Lectotypes are designated for M. albofasciata Friese 1900, M. caroli Cameron 1909, M. schultzei Friese 1909 and M. sibirica (Morawitz 1888). We described M. rasmonti n. sp., M. guichardi n. sp., the previously unknown male of M. bicollaris Warncke 1973 and unknown female of M. murciana Warncke 1973. 相似文献
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