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1.
Diapause is a protective response to unfavorable environments that results in a suspension of insect development and is most often associated with the onset of winter. The ls-tim mutation in the Drosophila melanogaster clock gene timeless has spread in Europe over the past 10,000 years, possibly because it enhances diapause. We show that the mutant allele attenuates the photosensitivity of the circadian clock and causes decreased dimerization of the mutant TIMELESS protein isoform to CRYPTOCHROME, the circadian photoreceptor. This interaction results in a more stable TIMELESS product. These findings reveal a molecular link between diapause and circadian photoreception.  相似文献   
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Intradermal tests were carried out on 18 horses with clinical signs of Culicoides hypersensitivity (CHS) and 23 horses without clinical signs of CHS, and sera from these horses were analysed by SDS-PAGE and Western blotting (W-B). Intradermal injections of 0.1 ml of 25 microg/microl sterile Culicoides extract, 0.1 ml of 1:10,000 histamine (positive control) and 0.1 ml of physiological saline (negative control) were made in the dermis of the middle region of the neck. Analysis of reactions indicated that a 1 cm wheal and a skinfold thickness >10% at 24 h represented a valid cut-off between horses with and without CHS. In these conditions the test, even in winter when clinical signs were absent, had 100% sensitivity and specificity. The W-B was performed after running Culicoides extract on a 12% polyacrylamide gel. The test revealed the presence of several bands with molecular weight ranging from 6 to 200 kDa. In particular, a band of 65 kDa was predominantly found in hypersensitive horses by using an anti-IgE antibody while in normal horses the same band was mainly detected by using an anti-IgG antibody. Our results demonstrated that the skin test is a valid diagnostic test, with high sensitivity and specificity and that the band of about 65 kDa probably corresponds to the allergen involved in the pathogenesis of CHS.  相似文献   
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The species Cynara cardunculus includes the globe artichoke (var. scolymus), the cultivated cardoon (var. altilis) and the wild cardoon (var. sylvestris). The three taxa are sexually compatible and originate fertile F 1 progenies, which, given the high heterozygosity of the species, are highly segregating. We report the characterization of two F 1 populations, one bred from a cross between globe artichoke and cultivated cardoon, and the other between globe artichoke and wild cardoon. Both populations featured a wide array of phenotypes in relation to several traits, and some of the newly developed genotypes are of interest for the ornamental market. The two populations were genotyped at 50 microsatellite (SSR) loci: in the globe artichoke × wild cardoon and globe artichoke × cultivated cardoon progenies 116 and 97 alleles were respectively detected. SSR pattern scores were used to produce an UPGMA dendrogram and a PCoA plot. A set of nine SSR loci, evenly dispersed across the genome, was shown to be sufficient to unambiguously identify each segregant. The molecular fingerprinting is useful for establishing the true to type correspondence of propagative materials in nurseries and ensures the effective correspondence between the real and the declared identity of a clone.  相似文献   
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Visceral Leishmaniasis (VL) is an emerging zoonotic parasitic disease caused by Leishmania infantum in Mediterranean countries, with sand flies (Phlebotomus spp.) as vectors and dogs as the main domestic reservoir. The role of wild carnivores in the epidemiology of leishmaniasis is still controversial. In order to determine the prevalence of natural infection with L. infantum in wild carnivores from Spain, we analyzed 217 samples by PCR and western blotting and used restriction fragment length polymorphism (RFLP) to compare the patterns present in wild carnivores with those of domestic dogs from the same areas. DNA of the parasite was detected in spleen or blood samples from 35 (16.12%) analyzed wild carnivores, including 8 of 39 (20.5%) wolves (Canis lupus), 23 of 162 (14.1%) foxes (Vulpes vulpes), 2 of 7 (28.6%) Egyptian mongooses (Herpestes ichneumon), 1 of 4 genets (Geneta geneta), and 1 of 4 Iberian lynxes (Lynx pardinus). No significant sex or age differences in prevalence were observed in wolves and foxes (P>0.05), but there was a significant difference among regions in foxes (P<0.05). A total of 12 PCR-RFLP patterns were found in foxes, 6 in wolves, 4 in dogs, 2 in Egyptian mongooses and 1 in lynx and genet. RFLP patterns differed between dogs and foxes in the two areas where they could be compared. This is the first study of canine leishmaniasis in wild canids and other carnivores from different regions of Spain by PCR. The prevalence of infection indicates the existence of natural infection in apparently healthy wild carnivore populations, and our results are suggestive of a sylvatic cycle independent of dogs.  相似文献   
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The ultrasonographic findings of kidneys, liver and urinary bladder of 288 Persian and 44 Exotic Shorthair clinically normal cats that underwent screening for polycystic kidney disease (PKD) between July 2003 and December 2005 were reviewed. Cats were divided into two groups, one including cats aged <9 months (group 1) and one cats aged >/=9 months (group 2). Cats were classified as PKD-positive when at least one renal cyst was found. One hundred and thirty-six cats (41.0%) had more than one cyst in at least one kidney. The prevalence of PKD was similar in both groups. Eight PKD-positive cats had cystic livers (5.9%). Other renal abnormalities included a pelvic calculus and a medullary rim sign (MRS). The difference in prevalence of an MRS in group 2 compared to group 1 and the difference between PKD-positive and -negative cats in group 2 were not significant. There was no difference in mean kidney length between PKD-positive and -negative cats in group 2. Urinary bladder anomalies were principally represented by urinary sediment, with prevalence significantly higher in group 2. No difference was detected in group 2 between PKD-positive and -negative cats. In conclusion feline PKD is common in Italy. The ultrasonographic findings of MRS and urinary bladder sediment did not correlate with feline PKD. Urinary bladder sediment is common in Persians and Exotic Shorthairs and more likely in adults.  相似文献   
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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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Species within the genus Hibiscus (Malvaceae) are herbaceous or woody plants, annuals or perennials. Within the genus, most of the domesticated species are grown as ornamentals, and the most widely exploited is Hibiscus rosa-sinensis, which is particularly variable with respect to flower colour and shape. H. rosa-sinensis is thought to have originated following hybridization between two species complexes endemic to different geographic locations.  相似文献   
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The red palm weevil (RPW), Rhynchophorus ferrugineus Olivier (Coleoptera, Curculionidae), is one of the most severe pests of ornamental palm species in urban areas of Mediterranean countries. Aiming to discover inhibitory semiochemicals for RPW population management in urban environments, we conducted electroantennographic (EAG) screenings of 17 commercially available synthetic compounds, representing three groups of plant volatiles (isoprenoids, phenyl propanoid derivatives and fatty acid derivatives) known for their repellent effects toward insects. These tests were followed by trap-based screenings of EAG-active menthone, α-pinene and methyl salicylate, singly and in combination, under urban conditions. In EAG bioassays, RPW antennae of both sexes showed positive dose-dependent responses to 13 of the 17 synthetic chemicals with significant differences among them. In field trapping experiments, conducted in the city of Palermo, Italy, from weeks 31 to 38 in 2010 and 2011, α-pinene, tested singly or in combination with methyl salicylate (2010) or menthone (2011), reduced trap catches by about 30% to 40%. Methyl salicylate and menthone alone were inactive. In conclusion, RPW is significantly affected by α-pinene. This isoprenoid is a promising disruptant for semiochemical-based management of this pest. In addition, identification of a large number of EAG-active chemicals could serve as a database for future design of active repellents or attractants of RPW adults.  相似文献   
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