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141.
Two previously developed platforms, a multiplex polymerase chain reaction (PCR) and a peptide nucleic acid (PNA) array, the former allowing for the simultaneous detection of five transgenes and two endogenous controls in food and feed matrices and the latter for the assessment of the identity of amplified PCR products, were combined in order to develop a PNA array device for the screening of genetically modified organisms (GMOs) in food. PNA probes were opportunely designed, synthesized, and deposited on commercial slides. The length of the probes as well as the distance of the probes from the surface were evaluated and found to be critical points. The most suitable probes were found to be 15-mer PNAs linked to the slide surface by means of two 2-(2-aminoethoxy)ethoxyacetic acids as spacers. The device was tested on a model system constituted by flour samples containing a mixture of standards at known concentrations of transgenic material, in particular Roundup Ready soybean and Bt11, Bt176, Mon810, and GA21 maize: The DNA was amplified using the specific multiplex PCR method and tested on the PNA array. The method proposed was found to be able to correctly identify every GMO present in the tested samples.  相似文献   
142.
Water, Air, & Soil Pollution - This paper is a review of the available literature on the main features of 11 of the most widely adopted oxygenated additives to base gasoline and diesel,...  相似文献   
143.
The European earwig, Forficula auricularia L. (Dermaptera: Forficulidae), is a well-known species that is cosmopolitan and present throughout Europe. Due to its omnivorous feeding behaviour, this species can act as a generalist predator, preying on several top fruit pests, but also as a pest causing shallow gouges or holes in stone and soft fruits such as apricots, strawberries, raspberries or blackberries. In Piedmont (NW Italy), significant fruit damage has been observed lately in apricot orchards where earwigs fed on ripening fruits and made a considerable part of the produce unmarketable. In this study, we sampled earwig populations in three apricot orchards in Piedmont and tested the effectiveness of glue barriers applied to the tree trunks in reducing both earwig density in the canopy and fruit damage. The arboreal glues Rampastop® and Vebicolla® were tested both in the field and laboratory trials. Glue barriers demonstrated to be effective control measures, significantly reducing earwig abundance in the canopy and fruit damage. Rampastop® gave better results on old trees with a very rough and cracked bark, since in that case Vebicolla® could not perfectly bond with the trunk.  相似文献   
144.
In recent years, watermelon (Citrullus lanatus) has been subjected to significant losses due to vine decline in Sicily (southern Italy). During a survey conducted in 2009, the predominant fungal species associated with root rot and vine decline were Rhizoctonia spp. The most isolates were characterized as binucleate Rhizoctonia AG-F through morphological observation, nuclear condition, anastomosis tests and sequence homology of rDNA-ITS. Occasionally, R. solani was found. The pathogenicity of binucleate Rhizoctonia and virulences of different isolates were tested in growth chamber on watermelon seedlings. All isolates were pathogenic on watermelon seedlings and showed statistically significant differences on the disease incidence and severity among them. To our knowledge, this is the first report worldwide of the occurrence of pathogenic binucleate Rhizoctonia responsible for root rot and associated with watermelon vine decline.  相似文献   
145.
146.
This study investigated for the first time the reproductive biology of Prochilodus lineatus in a system of rivers in southeastern Brasil, relating it to the role of tributary rivers in the reproductive success of this important commercial fish in the Upper Paraná River basin, where a cascade of hydroelectric dams were deployed. Specimens were caught bimonthly in three river sites: (S1) Grande River, downstream from the Porto Colômbia dam; (S2) Pardo River; and (S3) Mogi Guaçu River. Sex steroid plasma levels, fecundity, follicular atresia, oocyte diameter and gonadosomatic index (GSI) were compared among sites. In S1, fish exhibited changes in the reproductive parameters: lower GSI, oocyte diameter and fecundity and higher follicular atresia index, when compared to S2 and S3. Frequency of maturing fish was higher in S3 and spawning was only registered in S3. In sites S2 and S3, plasma concentrations of testosterone and 17β-estradiol in females and testosterone in males showed wide variations following gonadal maturation. Fish from S1 showed few significant variations in sex steroid concentrations throughout the gonadal cycle. These results indicate that P. lineatus does not reproduce in Grande River (S1), but probably uses the Pardo River (S2) as a migratory route towards the Mogi Guaçu River (S3) where they complete gonadal maturation and spawning. Our findings contribute for understanding the reproductive biology of P. lineatus and to highlight the importance of tributaries in impounded rivers as a favourable environment for migration and spawning of fish.  相似文献   
147.
148.
Ossification of the bladder wall, detected radiographically as a nonhomogeneous radiopaque area in the cranioventral part of the bladder in a puppy, is reported. We speculate that chronic inflammation due to the presence of uroliths in the lumen may have stimulated a metaplastic transformation of the cells.  相似文献   
149.
This study investigated the distribution of lipid droplets (LD) in immature canine oocytes in relation to their size and the reproductive stage. Oocytes were collected from the ovaries of bitches at different estrous stages, divided according to their size (110‐120 µm; >120 µm), and stained with Nile Red to detect lipid droplet distribution. At the follicular phase most of the oocytes displayed a diffuse pattern of LD distribution, whereas at anestrus and luteal phase oocytes showed LD mainly in a peripheral/ perinuclear LD distribution. A significantly higher intensity of LD has been recorded in the oocytes > 120 µm compared to those of smaller size (110 ‐ 120 µm) at all stages of the estrous cycle. At follicular phase, oocytes > 120 µm displayed LD intensity similar to that of oocytes > 120 µm at luteal phase and higher compared to the oocytes of the other groups.  相似文献   
150.
During the period January 2004 to December 2005 four different ostrich farms were investigated to evaluate the presence of thermotolerant Campylobacter. A total of 150 ostriches were examined and all were found to be clinically healthy. Campylobacter spp. were isolated from 60/150 cloacal swabs. Among the isolates, 48 were identified as Campylobacter jejuni whereas the remainder were identified as Campylobacter coli. Campylobacter lari was not isolated. The ostriches, although apparently in a healthy body condition, can be considered, theoretically, as potential Campylobacter carriers.  相似文献   
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