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61.
Hymenoptera wasps associated with the Asian gall wasp of chestnut (Dryocosmus kuriphilus) in Calabria,Italy 总被引:1,自引:0,他引:1
Vincenzo Palmeri Pasquale Cascone Orlando Campolo Saverio B. Grande Francesca Laudani Antonino Malacrinò Emilio Guerrieri 《Phytoparasitica》2014,42(5):699-702
The parasitoid complex of the Asian chestnut gall wasp Drycosmus kuriphilus Yasumatsu was studied in Calabria (Italy). A total of 14 different species of parasitoids were collected, of which three are recorded on the Asian gall wasp for the first time. The composition of the parasitoid complex collected in Calabria was compared with that reported from Italy and from Europe. The altitude of the sites of collection seemed to have an effect on the distribution and abundance of the single species of parasitoids. 相似文献
62.
Although soil algae are among the main primary producers in most terrestrial ecosystems of continental Antarctica, there are very few quantitative studies on their relative proportion in the main algal groups and on how their distribution is affected by biotic and abiotic factors. Such knowledge is essential for understanding the functioning of Antarctic terrestrial ecosystems. We therefore analyzed biological soil crusts from northern Victoria Land to determine their pH, electrical conductivity (EC), water content (W), total and organic C (TC and TOC) and total N (TN) contents, and the presence and abundance of photosynthetic pigments. In particular, the latter were tested as proxies for biomass and coarse-resolution community structure. Soil samples were collected from five sites with known soil algal communities and the distribution of pigments was shown to reflect differences in the relative proportions of Chlorophyta, Cyanophyta and Bacillariophyta in these sites. Multivariate and univariate models strongly indicated that almost all soil variables (EC, W, TOC and TN) were important environmental correlates of pigment distribution. However, a significant amount of variation is independent of these soil variables and may be ascribed to local variability such as changes in microclimate at varying spatial and temporal scales. There are at least five possible sources of local variation: pigment preservation, temporal variations in water availability, temporal and spatial interactions among environmental and biological components, the local-scale patchiness of organism distribution, and biotic interactions. 相似文献
63.
Antonio Santaniello Laura Rinaldi Lucia Francesca Menna Giuseppe Cringoli Alessandro Fioretti 《Research in veterinary science》2009,87(1):67-71
Rabbit sera (n = 1600) from 40 commercial farms were submitted to a serological screening for Encephalitozoon cuniculi by an enzyme-linked immunosorbent assay (ELISA) and a carbon immunoassay (CIA test). Antibodies anti-Encephalitozoon cuniculi were found in 505/1600 (31.6%) sera analysed, and all the farms (100%) resulted positive. Rabbits older than 4 months showed a significantly higher seropositivity for E. cuniculi (chi-squared test: p < 0.0001) than rabbits under 4 months, E. cuniculi sero-prevalence showed an increasing trend in rabbits within the farm along with the increase in the “number of rabbits on the farm”; however, this trend was not significant (Spearman’s correlation: p = 0.073).The findings of the present study confirm that rabbit is the main reservoir of E. cuniculi; they are of epidemiological relevance and immediate public health importance because of the recognized infectivity in humans by the microsporidium. 相似文献
64.
Romani A Vignolini P Isolani L Ieri F Heimler D 《Journal of agricultural and food chemistry》2006,54(4):1342-1346
Flavonoids and hydroxycinnamic derivatives of turnip tops (Brassica rapa L. subsp. sylvestris L.) were characterized for the first time in four samples from different origins. Turnip tops exhibit a high polyphenols content (ranging from 107 to 191 mg/100 g, fresh weight) and a good antiradical activity, determined with the DPPH* test. After a liquid-liquid extraction and fractionation procedures, most flavonoids (isorhamnetin, kaempferol, and quercetin glycosides) and hydroxycinnamic derivatives were identified by means of HPLC-DAD/MS techniques. Isorhamnetin glycosides were the main flavonoid derivatives, differing from that found in the vegetables belonging to the Brassica oleracea group. 相似文献
65.
Beatrice?Giannetta César?Plaza Costantino?Vischetti M.?Francesca?Cotrufo Claudio?ZacconeEmail authorView authors OrcID profile 《Biology and Fertility of Soils》2018,54(5):671-681
Accrual of carbon (C) and nitrogen (N) in soil is a significant and realizable management option to mitigate climate change; thus, a clear understanding of the mechanisms controlling the persistence of C and N in soil organic matter (SOM) across different ecosystems has never been more needed. Here, we investigated SOM distribution between physically and chemically stabilized fractions in soils from a variety of ecosystems (i.e., coniferous and broadleaved forest soils, grassland soils, technosols, and agricultural soils). Using elemental and thermal analyses, we examined changes in the quantity and quality of physically fractionated SOM pools characterized by different mechanisms of protection from decomposition. Independently of the ecosystem type, most of the organic C and total N were found in the mineral-associated SOM pool, known to be protected mainly by chemical mechanisms. Indexes of thermal stability and C/N ratio of this heavy SOM fraction were lower (especially in agricultural soils) compared to light SOM fractions found free or occluded in aggregates, and suggested a marked presence of inherently labile compounds. Our results confirm that the association of labile organic molecules with soil minerals is a major stabilization mechanism of SOM, and demonstrate that this is a generalizable finding occurring across different mineral soils and ecosystems. 相似文献
66.
IMAGING DIAGNOSIS—ULTRASONOGRAPHIC APPEARANCE OF SKELETAL MUSCLE METASTASES IN A DOG WITH HEMANGIOSARCOMA 下载免费PDF全文
Martina Fabbi Stefano Di Palma Sabrina Manfredi Giacomo Gnudi Francesca Miduri Eleonora Daga Gabriele Costantino Melis Ezio Bianchi Simone Voccia Antonella Volta 《Veterinary radiology & ultrasound》2017,58(6):E64-E67
A 13‐year‐old spayed female German shepherd dog was presented for acute onset of lethargy, anorexia, and disseminated erythematous skin lesions. Thoracic radiographs and abdominal ultrasonographic findings were consistent with metastatic hemangiosarcoma. Multiple, ill‐defined, irregularly shaped hypoechoic nodules were also detected within the thoracic and abdominal wall. Hemangiosarcoma metastases to the skeletal muscle were confirmed based on histopathological examination. Multivisceral involvement was also confirmed by necropsy. Metastatic neoplasia should be considered as a differential diagnosis for dogs with ill‐defined, irregular, hypoechoic, intramuscular nodules. 相似文献
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69.
Shesh Kumari Wilfrida Decraemer Francesca De Luca 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(2):243-250
Populations of Xiphinema brevicollum occurring in the Czech Republic were described morphologically and molecularly. Published species-specific primer set BL18
and BV3 was used to amplify three populations of X. brevicollum from the Czech Republic. These primers were tested against 9 species of Xiphinema and 11 species of Longidorus. Amplification was also observed for X. inaequale, X. italiae and X. lambertii. Three additional markers, mitochondrial cytochrome c oxidase subunit 1, ribosomal D2/D3 expansion segment of the 28S gene
and 18S gene, were amplified and sequenced for X. brevicollum, X. inaequale and X. lambertii belonging to X. americanum-group. Comparison of cox1 sequences of X. brevicollum from the Czech Republic with X. taylori from the Slovak Republic (accession number AM086702) suggested that these populations represent the same species. 相似文献
70.
Sudmant PH Kitzman JO Antonacci F Alkan C Malig M Tsalenko A Sampas N Bruhn L Shendure J; Genomes Project Eichler EE 《Science (New York, N.Y.)》2010,330(6004):641-646
Copy number variants affect both disease and normal phenotypic variation, but those lying within heavily duplicated, highly identical sequence have been difficult to assay. By analyzing short-read mapping depth for 159 human genomes, we demonstrated accurate estimation of absolute copy number for duplications as small as 1.9 kilobase pairs, ranging from 0 to 48 copies. We identified 4.1 million "singly unique nucleotide" positions informative in distinguishing specific copies and used them to genotype the copy and content of specific paralogs within highly duplicated gene families. These data identify human-specific expansions in genes associated with brain development, reveal extensive population genetic diversity, and detect signatures consistent with gene conversion in the human species. Our approach makes ~1000 genes accessible to genetic studies of disease association. 相似文献