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1.
Casimirella Hassler (1913) is accepted and Humirianthera Huber (1914) considered a synonym. Casimirella diversifolia and C. lanata from Brazil are described as new species. Casimirella ampla (Miers) based on Leretia ampla Miers, C. crispula (Howard) based on Humirianthera crispula Howard, and C. rupestris (Ducke) based on Humirianthera rupestris Ducke are new combinations.  相似文献   

2.
The filamentous fungus, Lambertella corni-maris (L. corni-maris), a mycoparasite on Monilinia fructigena, produces the antibiotics, lambertellols A (1), B (2), and lambertellin (3), in a substantial amounts under acidic conditions, whereas these antibiotics were hardly detected when the fungus was cultured on a potato-sucrose (PS) medium without added acids. Our investigations also revealed that the host, M. fructigena, changed its surroundings into acidic conditions, suggesting that the acidic conditions acted as kairomones that stimulated the production of 13.  相似文献   

3.

The formation of biogenic fabrics in limestone by two fungi, Serpula himantioides and a polymorphic fungal isolate from limestone identified as a Cephalotrichum (syn. Doratomyces) sp., was investigated. The fungal cultures were grown in laboratory microcosms consisting of Carboniferous limestone and after 21 d incubation at 25°C, biomineralization of fungal filaments was observed. Environmental electron scanning microscopy (ESEM) and X-ray micro-analysis (EDXA) of crystalline precipitates on the hyphae of S. himantioides demonstrated that the secondary crystals exhibited different crystalline forms but were similar in elemental composition to the original limestone. Powder X-ray diffraction (XRD) of crystalline precipitates showed they were composed of a mixture of calcite (CaCO 3 ) and calcium oxalate monohydrate (CaC 2 O 4 · H 2 O). Analysis of crystals precipitated on the hyphae of the limestone isolate, using ESEM and EDXA, showed that the crystals exhibited similar morphological characteristics and elemental composition to the original limestone. XRD showed that they were composed solely of calcite (CaCO 3 ) or of calcite with some calcium oxalate dihydrate (CaC 2 O 4 · 2H 2 O). These results provide direct experimental evidence for the precipitation of calcite (CaCO 3 ) and also secondary mycogenic minerals, on fungal hyphae in low nutrient calcareous environments, and suggest that fungi may play a wider role in the biogeochemical carbon cycle than has previously been appreciated.  相似文献   

4.
Uncaria rhynchophylla (Gouteng) is a famous traditional Chinese medicine used for psychiatric and hypotensive purposes in China. In this study, the ethyl acetate (EtOAc) part of U. rhynchophylla was revealed with protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Subsequent investigation on the EtOAc part yielded one new triterpenoid, 3β-formyloxy-6β,19α-dihydroxyurs-12-en-28-oic acid (1) and four known ones, 3β,6β,19α-trihydroxyurs-12-en-28-oic acid (2), 2-oxopomolic acid (3), 3β,19α-dihydroxy-6-oxo-olean-12-en-28-oic acid (4) and sumaresinolic acid (5). The structure of compound 1 was determined by extensive HRESIMS, IR, 1D and 2D NMR spectroscopic analyses. Two ursane-type triterpenoids (2 and 3) showed selective inhibition on PTP1B with IC50 values of 48.2 and 178.7 μM. The enzyme kinetic study suggested that compounds 2 and 3 were mix-type inhibitors on PTP1B with Ki values of 15.6 and 132.5 μM. This investigation manifests the antidiabetic potency of U. rhynchophylla with triterpenoids as the active constituents.  相似文献   

5.
Taxonomic changes are made to reflect a reassessment of morphology based on the results of molecular phylogenetic studies. A new genus, Davilanthus, is described to include six species that collectively form the sister group to Simsia, and includes the following species transferred from Viguiera: Davilanthus davilae, Davilanthus hidalgoanus, Davilanthus hypargyreus, Davilanthus huajuapanus, Davilanthus purpusii, and Davilanthus sericeus. Three species formerly placed in Viguiera ser. Grammatoglossae are transferred to Simsia: Simsia benziorum, Simsia ovata, and Simsia rhombifolia.  相似文献   

6.

During a research on gill ectoparasites of callichthyids fishes from the Peruvian Amazonia, the following monogenoideans were found: Philocorydoras peruensis n. sp. from Corydoras splendens (Castelnau); Philocorydoras multiradiatus n. sp. and Philocorydoras jumboi n. sp. from Brochis multiradiatus (Orcés, V.). All new species described herein are mainly differentiated from their congeners based on the morphology of the copulatory complex. In P. peruensis n. sp. the cirrus is “J”-like shaped tube slightly tilted to one side, while in P. jumboi n. sp. is “J”-like shaped tube in a straight position and in P. multiradiatus n. sp. the cirrus is an arced tube with inflated base and distally narrow. Brochis (Orcés, V.) represents a new genus hosting species of Philocorydoras. All new species presented in this work represent the first species of Philocorydoras reported for Peru.

  相似文献   

7.
Job Kuijt 《Brittonia》2009,61(2):144-162
Twelve new South American species of Loranthaceae (Aetanthus, Cladocolea, Oryctanthus, and Struthanthus) and Viscaceae (Dendrophthora and Phoradendron) are described and illustrated: Aetanthus trifolius, Cladocolea rostrifolia, Dendrophthora lanceolata, Dendrophthora rotundata, Dendrophthora tenuis, Dendrophthora werffii, Oryctanthus minor, Phoradendron pascoi, Phoradendron vasquezianum, Struthanthus apiculatus, Struthanthus schultesii, and Struthanthus sessiliflorus. Additionally, Cladocolea alternifolia, previously thought to be probably extinct, is reported to occur on Ilha Grande, just west of Rio de Janeiro, Brazil.  相似文献   

8.
Capsule: Grazing by livestock can have complex effects on drivers of population change in the Clamorous Reed Warbler Acrocephalus stentoreus and Dead Sea Sparrow Passer moabiticus.

Aims: To investigate the effect on two specialist bird species on wetland degradation in the Jordan Valley.

Methods: The direct and indirect effects of grazing on the probability of occurrences of two specialist bird species, Clamorous Reed Warbler A. stentoreus and Dead Sea Sparrow P. moabiticus, were analysed during the breeding season at the patch scale, using path analysis.

Results: Tamarix shrub density was a strong predictor for the presence of both species. Grazing had a negative total effect on both; a significant indirect effect on Dead Sea Sparrow via its impact on the mean height of shrubs, and a significant, negative indirect effect on Clamorous Reed Warbler by reducing reed cover. Intensive grazing and browsing by livestock including goats, sheep and camels, apparently had a negative effect on the overall density of native Tamarix shrubs, while promoting encroachment by invasive Prosopis juliflora.

Conclusion: This may be part of a long-term cascade leading to an ecological transition and loss of important wetland habitats in the arid Jordan Valley.  相似文献   

9.
Paulo H. Labiak 《Brittonia》2011,63(1):139-149
Stenogrammitis , a new genus of grammitid ferns, is segregated from Lellingeria based on morphological and molecular evidence. It differs from Lellingeria by linear leaves usually less than 5 mm wide, clathrate iridescent rhizome scales that are glabrous except for a single apical cilium, veins unbranched and only one per segment, fertile veins usually with the dark sclerenchyma visible beneath the sporangia, and x = 33. In contrast, Lellingeria has broader laminae, veins pinnate within the segments, and fertile veins not visible beneath the sporangia. Melpomene, which is sister to Stenogrammitis and Lellingeria, differs from those two genera by reddish setae on the leaves and rhizome scales papillate at the apex. Some species of Stenogrammitis are also distinctive by hemidimorphic laminae that have the fertile portion less dissected than the sterile. Stenogrammitis is pantropical and currently comprises 24 species, 12 of which occur in the Neotropics, six in Africa, four in Madagascar, and two on Pacific Islands. New combinations are made for Stenogrammitis aethiopica, S. anamorphosa, S. ascensionensis, S. boivinii, S. delitescens, S. jamesonii, S. hartii, S. hellwigii, S. hildebrandtii, S. limula, S. luetzelburgii, S. myosuroides, S. nutata, S. oosora, S. paucipinnata, S. prionodes, S. pumila, S. ruglessii, S. rupestris, S. saffordii, S. strangeana, S. tomensis, S. subcoriacea, and S. wittigiana. Lectotypifications are made for Grammitis muscosa, Polypodium itatiayense, P. oosorum var. micropecten, P. serrulatum forma major, P. serrulatum forma minor, S. luetzelburgii, S. myosuroides, and S. wittigiana. Illustrations are presented for the diagnostic characters of the genus, as well as a map with the geographical distribution.  相似文献   

10.
The in vivo and in vitro antiandrogenic activity of four new progesterone derivatives: 4-bromo-17α-(p-fluorobenzoyloxy)-4-pregnene-3,20-dione 1,4-bromo-17α-(p-chlorobenzoyloxy)-4-pregnene-3,20-dione 2, 4-bromo-17α-(p-bromobenzoyloxy)-4-pregnene-3,20-dione 3 and 4-bromo-17α-(p-toluoyloxy)-4-pregnene-3, 20-dione 4 was determined. These compounds were evaluated as antiandrogens on gonadectomized hamster prostate and reduced the weight of the prostate glands in gonadectomized hamsters treated with testosterone 5 (T) or dihydrotestosterone 6 (DHT) in a similar manner to that of commercially available finasteride, thus indicating a potent in vivo effect. The in vitro studies showed that steroids 14 have a weak inhibitory activity on 5α-reductase with IC50 values of: 280 (1), 2.6 (2), 1.6 (3) and 114?μM (4). The presence of Cl and Br atoms in the C-17 benzoyloxy group tends to increase the inhibitory potency of the compounds.

The binding efficiency of the synthesized steroids 14 to the androgen receptor of the prostate gland is also evaluated. All compounds form a complex with the receptor and this explains the weight reduction of the seminal vesicles in the animals treated with DHT plus steroids 14.  相似文献   

11.
Background: Species-rich Nardus stricta grasslands are a priority habitat for conservation in Europe. They typically occur on siliceous substrates and less frequently are found on calcareous bedrock.

Aims: The present paper aimed to identify the environmental factors (i.e. bedrock type, topographic, and climatic factors) that are related with community diversity and to assess if differences in plant diversity between N. stricta communities on calcareous and siliceous bedrock occur. We hypothesised that Nardus grasslands on calcareous bedrock hosted a higher vascular plant diversity than those on siliceous bedrock.

Methods: Based on 579 vegetation surveys carried out in the south-western Alps, we assessed vascular plant diversity (species richness, Shannon diversity, and Pielou’s equitability index) of species-rich Nardus grasslands and compared it between N. stricta communities on calcareous and siliceous bedrock.

Results: Elevation was identified as the main factor related to species composition, while species diversity was mostly related to mean annual precipitation and bedrock type. Species richness, Shannon diversity, and Pielou’s equitability index were higher within the communities on calcareous rather than on siliceous bedrock and a total of 89 and 34 indicator species were detected, respectively.

Conclusions: Based on our results, we suggest to protect primarily, as a habitat of priority interest, N. stricta grasslands on calcareous substrates for the higher vascular plant diversity hosted.  相似文献   

12.
Two new species, Hypogastrura analpapillata n. sp., on mushrooms from Yunnan Province, and Hypogastrura microspinata n. sp., on moss from Hunan Province, are described. Hypogastrura analpapillata n. sp. is the sixth species with highly modified mouthparts in the trybomi group. Hypogastrura microspinata n. sp. is close to H. yosii Stach 1964, but can be differentiated from the latter by body granules, tenent hair and lateral teeth on tibiotarsus. A key to Chinese species of Hypogastrura is provided and a list of Chinese Hypogastrura species and their distributional data are given.  相似文献   

13.

The sorptive behavior of bacteria—iron oxide composites was investigated in batch metal sorption assays using ferrihydrite in isolation (0.13 and 0.14 g/L ferrihydrite in cadmium and lead systems, respectively) as well as in combination with Bacillus subtilis (0.25 g/L adsorbent mixture) and Escherichia coli (0.27 g/L adsorbent mixture). A pH range from 3.0 to 6.5 was studied using total metal concentrations of 1.0 × 10 ? 4.0 and 3.2 × 10 ? 5 M with adsorbent mixtures proportioned on a 1:1 mass/volume basis. The log of the apparent surface complex formation constants (log K S M ) and sorption capacity (S max ) values were determined by fitting the experimental data to one-site Langmuir sorption isotherms. The one-site model effectively described the sorption data (r 2 > 0.9), where Cd 2 + exhibited somewhat lower sorption affinities (log K S M = ?3 for ferrihydrite, ?1.7 for B. subtilis–ferrihydrite, and ?1.1 for E. coli–ferrihydrite) than Pb 2 + (log K S M = ?0.9 for ferrihydrite, ? 0.2 forB. subtilis–ferrihydrite, and –0.1 for E. coli–ferrihydrite). The corresponding S max values for Cd 2 + and Pb 2 + on ferrihydrite were 0.78 mmole/g and 1.34 mmole/g, respectively. For the B. subtilis–ferrihydrite composites, Cd 2 + and Pb 2 + S max values were lower at 0.29 mmole/g and 0.5 mmole/g, respectively. Similar values were determined for the E. coli–ferrihydrite composites (0.15 mmole/g and 0.68 mmole/g for Cd 2 + and Pb 2 + , respectively). The sorption of Cd 2 + and Pb 2 + by each of the sorbent systems exhibited a strong dependence on pH with sorption edges in the range of pH 4.0 to 7.3. The observed S max of the composites were lower than values predicted upon available site additivity (Cd 2 + B. subtilis ?ferrihydrite : 0.29 mmole/g (observed) < 0.57 mmole/g (calculated); Cd 2 + E. coli ?ferrihydrite : 0.15 mmole/g (observed) < 0.44 mmole/ g (calculated); Pb 2 + B. subtilis ?ferrihydrite : 0.5 mmole/g (observed) < 0.805 mmole/g (calculated); Pb 2 + E. coli –ferrihydrite : 0.68 mmole/g (observed) < 0.775 mmole/g (calculated)), implying that a masking of reactive surface sites by attachment had occurred between the bacteria and ferrihydrite. Electrophoretic mobility analysis indicated that the ferrihydrite surface properties dominate the net surface charge for each composite system with lesser contributions from the bacteria.  相似文献   

14.
A group of 10 species belonging to the Neotropical tribe Acratini Alonso-Zarazaga, Lyal, Bartolozzi & Sforzi 1999, is shown to be monophyletic by a phylogenetic analysis based on 48 morphological characters. A new genus, Pertusius n. gen., is described, based on three derived characters of external and genital morphology: venter of prorostrum of males with fine median longitudinal carina, base of elytra with deep pit at the place of insertion on mesonotum, and proximal sclerite of endophallus more or less horseshoe-shaped. Eight species were previously known and, according to former authors, belonged to the genera Acratus Lacordaire 1865 [Pertusius apicalis (Sharp 1895), n. comb., P. errabundus (Kleine 1927), n. comb., P. extrarius (Kleine 1927), n. comb., P. fidus (Kleine 1927), n. comb. and P. telesi (Soares & Meyer 1959), n. comb.] and Proteramocerus Kleine 1921 [Pertusius chalcites (Perty 1832), n. comb., P. filum (Sharp 1895), n. comb., and P. laevis (Germar 1824), n. comb.]. Four new synonymies are proposed: Proteramocerus disparilis Soares & Dias 1971, n. syn. for Acratus apicalis Sharp 1895; Teramocerus laevigatus Boheman 1840, n. syn. for Arrhenodes chalcites Perty 1832; Acratus extraordinarius Kleine 1927, n. syn. for Acratus errabundus Kleine 1927; Proteramocerus diringshofeni Soares & Dias 1971, n. syn. for Acratus filum Sharp 1895. Two new species are described: Pertusius guyanensis n. sp. from French Guiana, and P. mexicanus n. sp. from Mexico (Yucatán Peninsula). Pertusius apicalis is newly cited from Bolivia and Peru, P. chalcites from Argentina and Paraguay, P. extrarius from Ecuador, P. fidus from Peru and P. telesi from Trinidad and Tobago and Venezuela. An identification key to species of the genus is provided.  相似文献   

15.
The reaction between 2-fluoroadenine (3) and 1,3,5-tri-O-benzyl-1-α-d-chloroarabinofuranose (4) with potassium t-amylate was evaluated in various solvents to afford 9-β-d-(2,3,5-tri-O-benzyl-arabinofuranosyl)-2-fluoroadenine (5) and the corresponding α-anomer (6). In addition, 7-β-d-(2,3,5-tri-O-benzyl-arabinofuranosyl)-2-fluoroadenine (7) and an unusual “bis-fluoroadenine” nucleoside (8) were isolated as by-products. The highest anomeric ratio (β/α > 10) and conversion (>80%) were observed with the highly polar solvent sulfolane. This reaction was demonstrated on gram scale as a practical laboratory synthesis of 5, a known intermediate in the synthesis of fludarabine.  相似文献   

16.
Sixteen new species of the genus Zorochros Thomson 1859 from China, Indonesia, Malaysia, Nepal and Thailand are described and illustrated, a key to the species of the Zorochros indicus group is given, and new records on already known species are provided. New species: Z. ahrensi n. sp., Z bingkorensis n. sp., Z. dabieshanensis n. sp., Z. dolini n. sp., Z. hartmanni n. sp., Z. hubeiensis n. sp., Z. karnaliensis n. sp., Z. magnificus n. sp., Z. naniensis n. sp., Z. nigredos n. sp., Z. platiai n. sp., Z schawalleri n. sp., Z. schmidti n. sp., Z. senaroensis n. sp., Z. theodori n. sp., and Z. tongshanensis n. sp.  相似文献   

17.
18.
Phytophthora infestans, the causal agent of late blight, threatens potato production worldwide. An important tool in the management of the disease is the use of resistant varieties. Eleven major resistance genes have been identified and introgressed from Solanum demissum. However, new sources of resistance are continually sought. Here, we report the characterization and refined genetic localization of a resistance gene previously identified as Rber in a backcross progeny of Solanum tuberosum and Solanum berthaultii. In order to further characterize Rber, we developed a set of P. infestans isolates capable of identifying each of the 11 R-genes known to confer resistance to late blight in potato. Our results indicate that Rber is a new resistance gene, different from those recognized in S. demissum, and therefore, it has been named R Pi-ber according to the current system of nomenclature. In order to add new molecular markers around R Pi-ber , we used a PCR-based mapping technique, named MASP-map, which located R Pi-ber in a 3.9 cM interval between markers CT240 and TG63 on potato chromosome X. The location of R Pi-ber coincides with an area involved in resistance to different pathogens of potato and tomato.  相似文献   

19.
为了解柯拉斯那(Aquilaria crassna)的化学成分,从其所产沉香中分离得到10个化合物,经波谱分析分别鉴定为:6,8-羟基-2-(2-苯乙基)色酮(1),6,8-二羟基-2-[2-(4-甲氧基苯)乙基]色酮(2),rel-(1a R,2R,3R,7b S)-1a,2,3,7b-tetrahydro-2,3-dihydroxy-5-(2-phenylethyl)-7H-oxireno[f][1]benzopyran-7-one(3),rel-(1a R,2R,3R,7b S)-1a,2,3,7b-tetrahydro-2,3-dihydroxy-[2-(4-methoxyphenyl)-ethyl]-7H-oxireno[f][1]benzopyran-7-one(4),rel-(1a R,2R,3R,7b S)-1a,2,3,7b-tetrahydro-2,3-dihydroxy-5-[2-(3-hydroxy-4-methoxyphenyl)-ethyl]-7H-oxireno[f][1]benzopyran-7-one(5),oxidoagarochromone B(6),oxidoagarochromone C(7),(5S,6R,7S,8R)-2-[2-(3′-hydroxy-4′-methoxyphenyl)ethyl]-5,6,7,8-tetrahydroxy-5,6,7,8-tetrahydrochromone(8),6,7-cis-dihydroxy-2-(2-phenylethyl)-5,6,7,8-tetrahydrochromone(9),N-trans-feruloyltyramine(10)。化合物3~5和8~10为首次从柯拉斯那沉香中分离得到。化合物1,3,6,7,9和10对乙酰胆碱酯酶具有一定的抑制活性,化合物4对人慢性髓原白血病细胞株K-562和人胃癌细胞株SGC-7901均具有较小的抑制作用,化合物1和3对人肝癌细胞株BEL-7402也有抑制活性。  相似文献   

20.
Diterpenoid alkaloids are compounds of pharmacological interest. Forty four C19 norditerpenoid (NDAs) and 23 C20 diterpenoid (DAs) alkaloids isolated from Aconitum, Delphinium and Consolida species were tested for their insecticidal effects (antifeedant and toxic) on Spodoptera littoralis and Leptinotarsa decemlineata, their cytotoxicity on tumoral cell lines with several multidrug resistance mechanisms, and their antiparasitic effects against Trypanososma cruzi and Leishmania infantum. Overall, C19 norditerpene alkaloids (NDAs) resulted better insect antifeedants and post-ingestive toxicants than the related C20 diterpene alkaloids (DAs). Their antifeedant or insecticidal potencies did not parallel their reported nAChR binding activity, but did correlate␣with the␣agonist/antagonist insecticidal/ antifeedant model proposed for nicotininc insecticides.␣Among the most potent antifeedants (EC50 < 0.2 μg/cm2) are␣the NDAs 1,14 diacetylcardiopetaline (10),␣18-hydroxy-14-O-methylgadesine (34) and 14-O-acetyldelectinine (28) (to CPB) and the DA 19-oxodihydroatisine (55) (to S.␣littoralis). DAs had strong antiparasitic effects with molecular selectivity while NDAs were inactive. Delphigraciline (53), 15,22-O-Diacetyl-19-oxo-dihydroatisine (56), azitine (64) and isoazitine (65) were active against L. infantum promastigotes and had a moderate effect on T. cruzi epimastigotes, while atisinium chloride (59) and 13-oxocardiopetamine (48) had a potent effect on T. cruzi epimastigotes. These compounds were not toxic to the host cell, significantly reduced parasite infection capacity and severely affected the multiplication of their extracellular forms. Several NDAs exhibited selective cytotoxicity to cancerous cells and some of these had irreversible effects on SW480, HeLa and SkMel25 cell lines (neoline 5, pubescenine 16, 14-deacetylajadine 26, lycoctonine 27, dehydrotakaosamine 35, and ajadelphinine 38). These cytotoxic effects could be related to the inhibition of ATP production.  相似文献   

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