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41.
Emericella qinqixianii, a new species isolated from desert soil from Sanchakou, Aksu, Qiemo, Yuli, Yutian, and the Taklimakan desert 100 km inland from Minfeng, Xinjiang Province, China, is described and illustrated. It is characterized by grayish yellow to olive brown, non-ostiolate ascomata surrounded by hyaline to pale yellowish brown hülle cells, membranaceous peridium, prototunicate asci, and violet-brown, lenticular ascospores with two equatorial crests, smooth convex surfaces, and long filiform appendages. It hasAspergillus anamorph with biseriate aspergilla.  相似文献   
42.
Invasive fish species impact aquatic ecosystems and modify native communities, often leading to a decline in local species. These ecological impacts include the transmission of pathogens, predation, competition as well as hybridization. Two invasive fish species, the common bleak Alburnus alburnus and the topmouth gudgeon Pseudorabora parva, have both been recently found co-occurring in several regions of southern Europe, such as the Italian Arno River. Nonetheless, the trophic relationships among invasive fish species, especially cyprinids, remain poorly understood, and no studies have reported the trophic interaction between these two species. This study compared length–weight relationship and used stomach content and stable isotope analysis of two co-occurring populations in the Arno River to characterize the growth and overlap of potential trophic niches. It also found similar allometric growth in both species, a wider generalist trophic niche for P. parva and a more specialized niche for A. alburnus. A considerable niche overlap was found, suggesting that feeding competition can occur if resources were to be limited. Moreover, the niche of P. parva was more likely to overlap with that of A. alburnus than vice versa, suggesting that P. parva can be considered as a potential over competitor. Nonetheless, the authors found in the overlapping populations no evidence of realized competition, probably avoided through a combination of fine-scale mechanisms. They also highlighted that these two invasive species can co-exist and share resources, at least in an open ecosystem like a river, thus potentially doubling up their trophic impact on local communities.  相似文献   
43.
Aluminum (Al3+) toxicity in acidic soils limits crop productivity worldwide. In this study, we found that putrescine (PUT) significantly alleviates Al toxicity in rice roots. The addition of 0.1 mM PUT promoted root elongation and reduced the Al content in the root apices of Nipponbare (Nip) and Kasalath (Kas) rice under Al toxicity conditions. Exogenous treatment with PUT reduced the cell wall Al content by reducing polysaccharide (pectin and hemicellulose) levels and pectin methylesterase (PME) activity in roots and decreased the translocation of Al from the external environment to the cytoplasm by downregulating the expression of OsNRAT1, which responsible to encode an Al transporter protein Nrat1 (Nramp aluminum transporter 1). The addition of PUT under Al toxicity conditions significantly inhibited ethylene emissions and suppressed the expression of genes involved in ethylene biosynthesis. Treatment with the ethylene precursor 1‐aminocylopropane‐1‐carboxylic acid (ACC) significantly improved ethylene emission, inhibited root elongation, increased the Al accumulation in root tips and the root cell wall, and increased cell wall pectin and hemicellulose contents in both rice cultivars under Al toxicity conditions. The ethylene biosynthesis antagonist aminoethoxyvinylglycine (AVG, inhibitor of the ACC synthase) had the opposite effect and reduced PME activity. Together, our results show that PUT decreases the cell wall Al contents by suppressing ethylene emissions and decreases the symplastic Al levels by downregulating OsNRAT1 in rice.  相似文献   
44.
Deng S  Hu H  Abliz P  Wan Z  Wang A  Cheng W  Li R 《Mycopathologia》2011,172(5):365-372

Objective  

To compare the efficacy and safety of terbinafine with griseofulvin in the treatment of tinea capitis in Western China.  相似文献   
45.
目的:以微核技术及精子畸变率为指示,探讨新疆大学红湖水质对模型动物致突变性作用。方法:采用小鼠嗜多染红细胞(PCE)微核率(MCN)及精子畸变率检测方法,研究红湖水质及其潜在的致突变性。结果:3个水样点的污水都能引起小白鼠嗜多染红细胞及精子细胞不同程度的遗传毒性。与对照组(自来水)喂养的小白鼠相比具有明显的差异(P<0.005)。结论:红湖水质已经被严重污染,对人体及动物具有潜在的危害。  相似文献   
46.
The zebra mussel Dreissena polymorpha is widely present in Italy, but Italian populations of this bivalve have never been genetically characterized. The mitochondrial Cytochrome Oxidase subunit I gene fragments have been used to determine the genetic structures of 3 populations from Lake Garda (n = 30), the first Italian basin colonized by this species, as well as 2 populations from Lake Constance, Germany (n = 14). A Neighbor-Joining tree and a Maximum Likelihood analysis were performed with 4 new Italian (LG1-LG4) and 3 German (LC1-LC3) haplotypes, also considering all the available Dreissena sequences from GenBank in order to estimate phylogeographic relationships. Almost all Italian haplotypes clustered with German and mid-European samples providing evidences of a mixed origin for Italian mussels. We speculate about Lake Garda colonization, for which the hypothesized "German origin" has been partially confirmed as well as the necessity of more efficient control strategies at least to minimize new colonizations.  相似文献   
47.
Neosartorya indohii and N. tsurutae, two new Neosartorya species isolated from tropical rainforest soil in the Amazonian area, Brazil, are described and illustrated. Neosartorya indohii is characterized by its spreading growth on Czapeks and malt extract agars, light yellow cleistothecia, broadly lenticular ascospores with two conspicuously serrate-incised equatorial crests and tuberculate convex surfaces, and globose to subglobose conidia with a smooth wall. Neosartorya tsurutae is characterized by its spreading growth on Czapeks and malt extract agars, white cleistothecia, broadly lenticular ascospores with four equatorial crests and rugulose-ruminate convex surfaces, and ovoid to broadly ellipsoidal conidia with a smooth wall.  相似文献   
48.
The regions in which Halyomorpha halys (Stål, 1855) occurs in Italy are summarized and ordered chronologically according to the date of the first record. Details and verification about the first Italian record from Liguria (often overlooked), that dates back to 2007 the introduction of H. halys in this country, are also given. First exact localities are listed for the Italian regions of Tuscany, Marche, Latium, Abruzzo, Campania, and Apulia, in which only general occurrence was known so far. We included also additional records from Trentino-Alto Adige, where the presence of H. halys has only recently been reported through a few data. Furthermore first records for Sweden, Central Macedonia (Greece), and Manitoba (Canada) are reported, as well as first intercepted specimens from Iceland.  相似文献   
49.
The inhibition of the poly(ADP-ribose) polymerase (PARP) family members is a strategy pursued for the development of novel therapeutic agents in a range of diseases, including stroke, cardiac ischemia, cancer, inflammation and diabetes. Even though some PARP-1 inhibitors have advanced to clinical setting for cancer therapy, a great deal of attention is being devoted to understand the polypharmacology of current PARP inhibitors. Besides blocking the catalytic activity, recent works have shown that some PARP inhibitors exhibit a poisoning activity, by trapping the enzyme at damaged sites of DNA and forming cytotoxic complexes.  相似文献   
50.
采用徒手切片法对新疆木灵藓属(Orthotrichum Hedw.)18种植物孢蒴上的气孔、茎和叶进行了比较解剖学观察。研究结果表明,木灵藓属植物茎横切结构形状稳定,由表皮和皮层组成,无中轴细胞分化;除半裸木灵藓(Orthotrichum hallii Sull.et Lesq.)外,其它种叶上部均为单层细胞;叶中部边缘外卷,叶细胞具有高度不同的分叉疣或单疣。在确定气孔显、隐型的基础上,茎和叶横切面的颜色、茎表皮和皮层细胞组成及细胞壁加厚程度、叶细胞疣的高度、叶中肋横切面的形状、中肋的宽度、细胞组成以及芽孢形态等特征可作为该属种间分类的依据。还根据18种木灵藓属植物孢蒴上的气孔显、隐型,及茎、叶的比较解剖学特征,编制了新疆木灵藓属植物的分种检索表。  相似文献   
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