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1.
Three new species are described in the cheilostomate bryozoan genus Schizoporella Hincks, 1877. British records of Scliizoporella dunkeri Reuss are shown to represent two previously unnamed species. Scliizoporella dunkeri is the senior synonym of the Adriatic species Schizoporella longirostris Hincks. Material of S. longirostris from British localities is referred in part to S. dunkeri and in part to a previously unnamed species.  相似文献   

2.
Five British species of Reteporella Busk, 1884 are described and figured. A neotype specimen is selected for R. beaniana (King), and R. incognita sp. nov. is described, and distinguished from R. couchii (Hincks).  相似文献   

3.
Tagalina semperi Dohrn and T. papua (Bormans) are shown to be distinct species. T.burri Hincks is synonymised with T. erythronota Gunther, and a lectotype is designated for the latter species. The specimens misidentified by Hincks as T. erythronota are described as hincksi sp.n., and curta sp.n. is described from central New Guinea. A key to the nine species of the genus is given, together with a short systematic list and notes on the distributions and type localities.  相似文献   

4.
Sequence data of the rbc L –rbc S noncoding intergenic spacer of the plastid genome for 47 specimens of Porphyra and Bangia from the northeast Atlantic reveal that they fall into 11 distinct sequences: P. purpurea, P. dioica (includes a sample of P. "ochotensis" from Helgoland), P. amplissima (includes P. thulaea and British records of P. "miniata" ), P. linearis, P. umbilicalis, P. "miniata", B. atropurpurea s.l. from Denmark and B. atropurpurea s.l. from Wales, P. drachii, P. leucosticta (includes a British record of P. "miniata var. abyssicola" ), and P. "insolita" (includes P. "yezoensis" from Helgoland). Of these, data obtained for P. purpurea , P. dioica, P. amplissima, P. linearis, P. umbilicalis, P. drachii, and P. leucosticta were based on type specimens or material compared with types. Comparison of sequence data for Porphyra spp. and Bangia atropurpurea s.l. (including B. fuscopurpurea, the type species of Bangia ) confirms that the species are congeneric. The data also confirm that the number of layers that make up the Porphyra thallus are not taxonomically significant. Comparison of sequence data for species from the northeast Atlantic with those for material of two species from the Pacific reveals that the species fall into two distinct groupings: an Atlantic group, containing P. purpurea, P. dioica, P. amplissima, P. linearis, P. umbilicalis, P. "miniata", and B. atropurpurea, and a Pacific group, containing P. "pseudolinearis", P. drachii, P. leucosticta, P. "yezoensis" (including a sample of P. "tenera" ), and P. "insolita" (including P. "yezoensis" from Helgoland). The possibility of alien species in the northeast Atlantic is discussed.  相似文献   

5.
Based on a collection of earwigs from Simla hills (Himachal Pradesh) and Kashmir, two new species, namely Diplatys srivastavai and Forficula meenae have been described and Diplatys chinensis Hincks is recorded from India for the first time.  相似文献   

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The presence of characteristic epithelial swirls called Hassall bodies within the human thymic medulla has been used as an indicator of ongoing or recent thymopoiesis. We present a case where Hassall bodies were present in the absence of current or past thymopoiesis. The patient had been treated with corticosteroids for presumed asthma before his diagnosis of X-linked SCID. Two other cases of nonimmunodeficient patients treated with high-dose corticosteroids had markedly increased numbers of thymic Hassall bodies. To determine whether corticosteroid treatment induces thymic epithelial (TE) differentiation to form Hassall bodies, mAbs reactive with specific cytokeratins (CKs), filaggrin, and involucrin were used to define distinct stages of TE cell differentiation. Treatment of primary TE monolayers with hydrocortisone in vitro induced expression of involucrin and high-molecular-mass CKs that are characteristic of TE differentiation. Treatment of thymic organ cultures with hydrocortisone induced both medullary and subcapsular cortical TE cells to express CK6, a differentiation marker that is normally expressed only by Hassall bodies in vivo. These experimental studies combined with the case observations indicate that exogenous corticosteroids can regulate terminal differentiation of TE cells both in vitro and in vivo. Thus, the presence of Hassall bodies in thymus from corticosteroid-treated patients cannot be taken as an absolute indication of previous thymopoiesis. Because corticosteroids are also made within the thymus under normal physiologic conditions, these studies support the hypothesis that endogenous corticosteroids may play a role in normal TE differentiation and Hassall body formation in vivo.  相似文献   

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9.
The processed leaves and stems of Aspalathus linearis contain a new diastereomeric pair of the flavanones, (S)- and (R)-eriodictyol-6-C-beta-D-glucopyranoside, which is also formed via the oxidative cyclization of the dihydrochalcone, aspalathin, under conditions which mimic the fermentation process.  相似文献   

10.
The shoots of the South African legume Aspalathus linearis spp. linearis (A. linearis) are used in the manufacture of an increasingly popular beverage that has acclaimed beneficial effects on health; this important export product is known as Rooibos (or Redbush) tea. Three strains of Bradyrhizobium aspalati, which are the nitrogen-fixing symbionts of Aspalathus carnosa, A. hispida and A. linearis, were tested for the production of lipo-chitin oligosaccharide signal molecules using thin-layer chromatographic analysis after induction with different inducers, including Rooibos tea extract, and radioactive labelling. Large-scale separation, using high-performance liquid chromatography, of lipo-chitin oligosaccharides from B. aspalati isolated from A. carnosa was performed for structural characterisation using fast-atom bombardment mass spectrometry and chemical modifications followed by gas chromatography-mass spectrometric analysis. The strain was shown to secrete a family of unusual lipo-chitin oligosaccharides that are highly substituted on the nonreducing-terminal residue but unsubstituted on the reducing-terminal residue. They have a backbone of three to five beta-(1-->4)-linked N-acetyl-D-glucosamine residues substituted on the nonreducing terminus with a C16:0, C16:1, C18:0, C18:1, C19:1cy, or C20:1 fatty acyl chain, and are both N-methylated and 4,6-dicarbamoylated.  相似文献   

11.
Haplogloia andersonii (Farlow) Levring is an anti-tropical species that occurs on cold and warm-temperate Pacific coasts of both Americas. In its habit it resembles the subantarctic species Chordaria linearis (Hooker et Harvey) Cotton. Culture studies show that the species differ in morphology and ecophysiology of their microscopic gametophytes and in gamete behavior. Details of sporophyte anatomy are presented that also allow the distinction of field plants. In South America, H. andersonii occurs only on the Pacific coast, from central Perú (14°S) to southern Chile (50°S). Chordaria linearis occurs on the Pacific coast from Chiloé Island (43°S) to Cape Horn (56°S). In the shared area the species may co-occur. On the Atlantic coast, C. linearis was newly collected at a locality in northern Patagonia (41°S). In addition, C. linearis occurs in Antarctica. Haplogloia moniliformis Richer, recently described from Macquarie Island, is probably synonymous with Chordaria linearis.  相似文献   

12.
A new nematode species, Rhabdias lacertae n. sp. (Rhabdiasidae), is described from the body-cavity of the common lizard Lacerta vivipara Jacquin (Lacertidae) from the Ridge of Malá Fatra (Sokolie Hill), north-western Slovakia. The new species differs from its congeners mainly in possessing 3 min cuticular spikes at the tail tip and some other features. This is the first species of Rhabdias Stiles & Hassall, 1905 described from lizards in Europe and the first species of this genus parasitising hosts belonging to the Lacertidae.  相似文献   

13.
报道了2006~2007年9月间采自中国吉林、辽宁两省的舟形藻科中国新记录植物5种5变种,分别为Navicula arkona Lange-Bertalot & Witkowski, Hippodonta linearis(0strup) Lange-Bertalot, Metzehin & Witkowski, Geissleria decussis (Hustedt) Lange-Bertalot & Metzehin, Geissleria kriegeri ( Krasske ) Lange-Bertalot & Metzehin, Pinnularia divergens var. media Krammer, Pinnularia dubitabilis var. minor Krammer, Pinnularia lundii var. lirvearis Krammer, Pinnularia rhombarea var. variarea Krammer, Pinnularia stomatophora var. irregularis Krammer, Alveovallum beyensii Lange-Bertalot & Krammer。对部分种类进行了光镜观察,部分种类进行了扫描电镜观察;对它们的分类学特征进行了详细的描述,并记录了它们的生境特征。  相似文献   

14.
Two new Stenhelia (Stenhelia) species are described: 5. (S.) diegensis from 1200 m depth in San Diego Trough, California and 5. (S.) asetosa from the intertidal of Nanaimo Estuary, British Columbia. S. (S.) diegensis differs from previously known species in having but one seta on the terminal segment of the P, endopod. 5. (S.) asetosa lacks inner setae on the first segments of the P2–P, exopods. A table listing the salient morphological features of the species of Stenhelia (Stenhelia) is given as is a new key to the subgenus.  相似文献   

15.
The lichen flora of high ground in the west of Ireland is described by reference to four localities (Brandon Mountain, Muckanaght, Ben Bulben, Slieve League). These were selected on the basis of their reputation for calcicolous alpine vascular plants and for being some of the most highly oceanic mountains in Europe. The montane element in the lichen flora is strictly limited, populations being small and isolated, although sub-montane species are more frequent. A small group of 44 species has been identified, which is 30% fewer than is found in either the Lake District or Snowdonia; their distribution and ecology are described. The margin of high-level tarns on Brandon Mountain support communities of outstanding importance, includingRinodina fimbriata, new to the British Isles. Seventeen lichens are reported as being new to Ireland. 1996 The British Lichen Society  相似文献   

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18.
记述了中国瘿蚊科1新纪录属异瘿蚊属及一新种:横瓣异瘿蚊Heterogenella transversa.spn.nov.,模式产地云南中甸虎跳峡;中国3新纪录种;达氏异瘿蚊H.dolini Berest(四川理县米亚罗),短须异瘿蚊H.hybrida Mamaev(内蒙古额尔古纳旗莫尔道嘎)和纵缝异瘿蚊H.linearis Yukawa(云南丽江玉龙山)。文中给出了异瘿蚊属中国已知种类分种检索表。模式标本保存于南开大学生物系昆虫标本室。  相似文献   

19.
C-Glycosylflavonoids. The chemistry of aspalathin   总被引:1,自引:0,他引:1  
1. The isolation of aspalathin, the principal phenolic constituent in the leaves of Aspalathus linearis, is described and its properties are discussed. 2. The compound has been identified as 3'-C-beta-d-glucopyranosyl-2',3,4,4',6'-pentahydroxydihydrochalcone by the preparation and analysis of various derivatives, by photochemical oxidation to 2,3-dihydroiso-orientin and by nuclear-magnetic-resonance studies.  相似文献   

20.
相互干扰的捕食与被捕食者种群的Hassall模型定性分析   总被引:1,自引:0,他引:1  
本文证明了Hassall模型的渐近稳定性、有界性、全局稳定性。解决了文献[1]对该模型的三个猜想:(1)模型在某种条件下,正平衡点(x^*,y^*)是渐近稳定的;(2)模型的一切正初始条件的解有界;(3)模型在一定条件下,正平衡点(x^*,y^*)是全局稳定的。  相似文献   

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