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1.
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   

2.
【目的】通过基因组挖掘的方法,研究红树林来源白骨壤链霉菌Streptomyces avicenniae 9-9中多环稠合大环内酰胺(PTMs)类化合物的结构多样性。【方法】通过生物信息学分析白骨壤链霉菌基因组序列,寻找PTMs类化合物的生物合成相关基因;利用UPLC-MS/MS技术对该菌的次级代谢产物进行分析。【结果】在白骨壤链霉菌基因组中发现PTMs生物合成基因簇(aviA-D);从菌液提取物中鉴定出5个PTMs类化合物,其中包括ikarugamycin(化合物1)和capsimycin B(化合物2);基于PTMs类化合物5-6-5环类型的MS/MS碎裂规律,对化合物3–5的结构进行了推测。【结论】红树林来源白骨壤链霉菌S.avicenniae 9-9具有产生5-6-5环类型的PTMs类化合物的能力。  相似文献   

3.
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   

4.
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   

5.
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   

6.

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   

7.
Five fluorescent symmetrical dimeric bisbenzimidazoles DB(n) containing four 2,6-substituted benzimidazole cores and differing in the length of the oligomethylene linker between two bisbenzimidazole rings (n = 3, 4, 5, 7, 11) have been synthesized. The ability of the dimeric bisbenzimidazoles to form complexes with the double-stranded DNA has been shown by spectral methods. Upon binding to the double-stranded DNA, DB(n) are localized in the narrow groove. The data on the inhibition of the DNA methyltransferase Dnmt3a by DB(n) indicate that dimeric bisbenzimidazoles DB(3) and DB(11) site-specifically bind to the oligonucleotide duplex.  相似文献   

8.

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   

9.
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   

10.

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   

11.
目的 探讨取消药品加成政策的实施对县级公立医院经济运营所产生的影响。方法 运用对比研究的方法对四川省6家试点县级公立医院的经济运行状况进行分析。结果 取消药品加成政策实施后县级公立医院收支结余下降,补偿渠道发生变化。结论 加强政府财政投入和相关政策的落实力度,警惕医院将取消药品加成损失向其他收费项目转移。  相似文献   

12.
目的 基于常见病、多发病的视角界定基层医疗卫生机构的基本医疗服务范围。方法 以广东省A市为例,根据该市基本医疗保险参保人的微观数据,统计分析了该市的常见病、多发病,并对该市128个医疗机构进行问卷调查。结果 分别确定了社区卫生服务中心104个病种、乡镇卫生院101个病种、社区卫生服务站38个病种和村卫生室34个病种作为四类基层医疗卫生机构的基本医疗服务范围。结论 应依据四类基层医疗卫生机构的基本医疗服务范围从诊疗项目、药品目录、基层首诊制等方面进行政策调整与完善。  相似文献   

13.
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   

14.
西藏拉鲁湿地水体酵母菌多样性及其与理化因子相关性   总被引:1,自引:1,他引:0  
【目的】开展拉鲁湿地水体酵母菌多样性研究,探究理化因子与酵母菌群落结构的相互关系。【方法】采用原位培养法从拉鲁湿地11个水样中分离酵母菌,应用26S r RNA D1/D2区域序列分析,并结合经典分类法对获得的菌株进行分类鉴定,运用SPSS和CANOCO软件分析酵母菌多样性及其与环境因子相关性。【结果】从拉鲁湿地水体中分离得到169株酵母菌,鉴定分属为15个属31个种。优势种为Ustilentyloma graminis和Filobasidium magnum,优势属为Naganishia、Ustilentyloma、Filobasidium和Cystofibasidium。统计分析结果表明,化学需氧量(COD)是影响拉鲁湿地水体酵母菌数量的显著因素,另外,此理化因子是影响Ustilentyloma分布的重要环境条件。【结论】西藏拉鲁湿地酵母菌资源比较丰富,且存在明显的空间异质性。  相似文献   

15.
Nine new species of the genus Heliura are described from Brazil (H. brasiliana sp. nov., H. olivocolora sp. nov., H. pulcherrima sp. nov., and H. laerteae sp. nov.), Ecuador (H. ecuadoris sp. nov.), Peru (H. flavipennis sp. nov. and H. peruana sp. nov.), and Venezuela (Heliura albiventris sp. nov. and H. juliani sp. nov.). They are illustrated in habitus and genitalia, and their phylogenetic affinities are discussed based on morphological evidence.  相似文献   

16.
目的 利用数据包络分析方法评价厦门市某三级综合性医院临床科室的配置效率,为医院管理者提供有益的决策信息。方法 在Excel的规划求解模块上进行数据包络分析计算,得出各临床科室的相对效率得分。结果 数据包络分析有效单元为15个,其余单元不同程度存在产出不足的现象。结论 大型综合性医院在自身的生存和发展中,应注重以资源调整和优化配置为主的内涵式发展。  相似文献   

17.
18.
目的 对公立医院卫生人才流失现状进行实证研究,分析其原因并提出相应对策。方法 采用分层抽样方法对潍坊市29家公立医院卫生人才进行问卷调查。结果 公立医院卫生人才流失现象较为普遍,流失率为30.9%,流失原因多为个人发展、薪酬、执业环境。结论 应采取相应对策提高公立医院卫生人才的稳定性,完善相应的管理机制,规范人才的合理流动。  相似文献   

19.
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   

20.
To determine if microbial species play an active role in the development of calcium carbonate (CaCO 3 ) deposits (speleothems) in cave environments, we isolated 51 culturable bacteria from a coralloid speleothem and tested their ability to dissolve and precipitate CaCO 3 . The majority of these isolates could precipitate CaCO 3 minerals; scanning electron microscopy and X-ray diffractrometry demonstrated that aragonite, calcite and vaterite were produced in this process. Due to the inability of dead cells to precipitate these minerals, this suggested that calcification requires metabolic activity. Given growth of these species on calcium acetate, but the toxicity of Ca 2+ ions to bacteria, we created a loss-of-function gene knock-out in the Ca 2+ ion efflux protein ChaA. The loss of this protein inhibited growth on media containing calcium, suggesting that the need to remove Ca 2+ ions from the cell may drive calcification. With no carbonate in the media used in the calcification studies, we used stable isotope probing with C 13 O 2 to determine whether atmospheric CO 2 could be the source of these ions. The resultant crystals were significantly enriched in this heavy isotope, suggesting that extracellular CO 2 does indeed contribute to the mineral structure. The physiological adaptation of removing toxic Ca 2+ ions by calcification, while useful in numerous environments, would be particularly beneficial to bacteria in Ca 2+ -rich cave environments. Such activity may also create the initial crystal nucleation sites that contribute to the formation of secondary CaCO 3 deposits within caves.  相似文献   

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