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排序方式: 共有181条查询结果,搜索用时 31 毫秒
21.
Determination of some heavy metals and selenium in Sicilian and Calabrian citrus essential oils using derivative stripping chronopotentiometry 总被引:1,自引:0,他引:1
La Pera L Lo Curto R Di Bella G Dugo G 《Journal of agricultural and food chemistry》2005,53(13):5084-5088
This paper aims to bring some novelty about the concentration of some heavy metals and selenium in biological citrus essential oils (CEO) produced in Sicily and Calabria in different crop years. Derivative stripping chronopotentiometry has been used as an accurate, sensitive, and rapid technique for the determination of Cd, Cu, Mn, Ni, Pb, Zn, and Se in hydrochloric acid extracts of CEO; in the optimized electrochemical conditions, detection limits of <1 microg kg(-1) were obtained for all of the studied metals. In particular, the concentrations of metals were determined in biological bergamot essential oils produced in Calabria in 1999 and 2000 and in biological CEO produced in Sicily in 2003 and 2004. The obtained results provided evidence that Mn was the most abundant metal in all of the studied CEO followed by Zn, Ni, Cu, Pb, and Se; Cd concentrations were always lower than the limit of detection (0.6 microg kg(-1)). 相似文献
22.
Yabsley MJ McKibben J Macpherson CN Cattan PF Cherry NA Hegarty BC Breitschwerdt EB O'Connor T Chandrashekar R Paterson T Perea ML Ball G Friesen S Goedde J Henderson B Sylvester W 《Veterinary parasitology》2008,151(2-4):279-285
To identify the tick-borne pathogens in dogs from Grenada, we conducted a serologic survey for Ehrlichia canis in 2004 (104 dogs) and a comprehensive serologic and molecular survey for a variety of tick-borne pathogens in 2006 (73 dogs). In 2004 and 2006, 44 and 32 dogs (42.3% and 43.8%) were seropositive for E. canis, respectively. In 2006, several tick-borne pathogens were identified by serology and PCR. DNA of E. canis, Anaplasma platys, Babesia canis vogeli, Hepatozoon canis, and Bartonella sp. were identified in 18 (24.7%), 14 (19.2%), 5 (7%), 5 (7%), and 1 (1.4%) dogs, respectively. Six (8.2%) dogs were seropositive for Bartonella vinsonii subsp. berkhoffii. All dogs were seronegative and PCR-negative for Rickettsia spp. Coinfection with two or three pathogens was observed in eight dogs. Partial 16S rRNA E. canis and A. platys sequences were identical to sequences in GenBank. Partial 18S rRNA gene sequences from the Grenadian H. canis were identical to each other and had one possible mismatch (ambiguous base) from H. canis detected from Spain and Brazil. Grenadian B. c. vogeli sequences were identical to B. c. vogeli from Brazil and Japan. All of the detected pathogens are transmitted, or suspected to be transmitted, by Rhipicephalus sanguineus. Results of this study indicate that dogs from Grenada are infected with multiple tick-borne pathogens; therefore, tick-borne diseases should be included as differentials for dogs exhibiting thrombocytopenia, leukopenia, fever, or lethargy. One pathogen, E. canis, is also of potential public health significance. 相似文献
23.
24.
Matthew R. Lanza Ayla R. Musciano Richard D. Dubielzig Amy C. Durham 《Veterinary ophthalmology》2018,21(2):167-173
The objectives of this retrospective study of 100 dogs with intraocular lymphoma were to describe the histomorphologic and immunohistochemical features of canine intraocular lymphoma, determine the proportion of cases with presumed solitary ocular lymphoma (PSOL) compared to multicentric disease, and assess the clinical outcomes of these patients. Selected cases from Penn Vet Diagnostic Laboratory and Comparative Ocular Pathology Lab of Wisconsin (2004–2015) were evaluated and subtyped using the WHO classification system. Peripheral T‐cell lymphoma and diffuse large B‐cell lymphoma were the two most common subtypes. Questionnaires were distributed to the referring veterinarians and veterinary ophthalmologists inquiring about clinical signs at time of enucleation, staging, patient outcome, treatment, and disease progression. Cases were categorized as PSOL if only ocular involvement was noted at the time of diagnosis based on the clinical staging criteria. The majority of cases (61%) did not have systemic involvement at the time of diagnosis, and these cases did not progress postoperatively. Median survival time (MST) was significantly higher for the presumed solitary intraocular cases: 769 vs. 103 days, hazard ratio of 0.23 (95% CI: 0.077–0.68). The subtype of lymphoma did not affect survival time. The results of this study suggest two significant points of clinical interest: the majority of dogs (61%) presented without signs of systemic involvement of lymphoma at the time of enucleation, and dogs with only ocular involvement showed no disease progression postenucleation. 相似文献
25.
Bonazzi M Volta A Gnudi G Bottarelli E Gazzola M Bertoni G 《Journal of Feline Medicine and Surgery》2007,9(5):387-391
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
26.
de la Lanza Espino Guadalupe Flores Verdugo Francisco 《Water, air, and soil pollution》1998,107(1-4):105-120
In order to balance the impact of agricultural development on land around coastal lagoons with the protection of aquatic resources, knowledge of the role of the sedimentary phase in the entrapment or availability of nutrients in the water column in areas affected by agroindustrial outlets is important. The Ensenada del Pabellon coastal on the Pacific coast of Mexico was chosen to be analyzed. The input of ammonium and orthophosphate from sediment using semicontrolled benthic chambers near a sugar cane factory outlet was compared to non altered sediment. Phosphate and ammonia loading from agroindustrial outlets has been the primary cause of eutrophication. The inputs of ammonium and orthophosphates from the sediment to the water column depend on their concentration in the agroindustrial outlet's waste water, the local morphology, the tide, and biotic assimilation, in order of importance. Sediment in non-altered revealed maxima of 7.8 mg m-2 d-1 of NH+ 4 and 1.4 mg m-2 d-1 of PO-3_4, whereas in one outlet that greatly transfigures the environment, maxima of 223 mg m-2 d-1 of NH+ 4 and 67 mg m-2 d-1 of PO-3_4 were recorded, which represent an increase greater than 20 times the normal diffusion. These figures varied markedly in space and time. Results from the study indicated that existing levels of nutrient could endanger the future of this ecosystem, including its sustainable fisheries. 相似文献
27.
Mandalari G Bennett RN Bisignano G Saija A Dugo G Lo Curto RB Faulds CB Waldron KW 《Journal of agricultural and food chemistry》2006,54(1):197-203
Bergamot peel is an underutilized byproduct of the essential oil and juice-processing industry. As with other Citrus peels, it still contains exploitable components, such as pectins and flavonoids. Commercial glycoside hydrolases, specifically a combination of pectolytic and cellulolytic enzymes, solubilized a high percentage of the material (81.94%). The flavonoid profile of the peel consisted of characteristic Citrus species flavanone rutinosides and neohesperosides derived from naringenin, eriodictyol, and hesperetin. In addition, a number of minor flavanone and flavone glycosides, not found in orange and lemon peels, were identified. The majority of flavonoids were extracted in the two 70% v/v EtOH extractions. Processing this material clearly has economic potential leading to low environmental impact. 相似文献
28.
Roberto Pilli Stephen J. Kull Viorel N. B. Blujdea Giacomo Grassi 《Annals of Forest Science》2018,75(3):71
Key message
The purpose of this report is to increase the transparency of applications of the CBM-CFS3 model by climate-related policy-makers and researchers. The report provides explicit information on the parametrization of a new Archive Index Database used with this model to simulate forest carbon dynamics in 26 EU countries. The database can be accessed at https://data.europa.eu/89h/jrc-cbm-eu-aidb , primary metadata are available in Kull et al. (2017), and additional metadata are available at https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/df48155b-973f-4169-a722-100bb6bfc76c .The Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) has been adapted, tested, and applied to forests of 26 EU countries over the last 7 years for EU policy making and scientific research. The overall purpose of this exercise is to increase the transparency of how the EU Archive Index Database (EU-AIDB) was parameterized while supporting both the policy making and research communities interested in applying the CBM-CFS3 with ecological parameters specific to the EU context. In addition to preparing model input data reflecting various management and disturbance scenarios for CBM-CFS3 projects, an essential step was to update the original AIDB with information specific to the EU context and create an EU-AIDB. The AIDB is the Microsoft Access database behind the CBM-CFS3 that stores default ecological information and parameters pertaining to the forest ecosystems of a country, among other functions. The EU-AIDB incorporates 1034 spatial units resulting from the intersection of 204 European administrative regions and ecological boundaries representing 35 climatic units. It also contains updated parameters for 192 of the main tree species reported by the National Forest Inventories of each EU country. The release of this database allows CBM-33 CFS3 users in the EU to apply European administrative and ecological units and tree species in forest carbon modeling projects.29.
IMAGING DIAGNOSIS—ULTRASONOGRAPHIC APPEARANCE OF SKELETAL MUSCLE METASTASES IN A DOG WITH HEMANGIOSARCOMA
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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
30.
Passamonti F Veronesi F Cappelli K Capomaccio S Coppola G Marenzoni ML Piergili FD Verini SA Coletti M 《Comparative immunology, microbiology and infectious diseases》2010,33(1):73-83
Anaplasma phagocytophilum, the causative agent of granulocytic ehrlichiosis, affects several species of wild and domesticated mammals, including horses. In this work we compared direct and indirect methods to evaluate A. phagocytophilum presence in Central Italy: 135 sera were screened by IFA for A. phagocytophilum and other haemopathogens (Theileria equi and Babesia caballi). Each horse was also tested for A. phagocytophilum 16S rRNA with a nested-PCR technique. In order to examine the risk of A. phagocytophilum transmission, 114 ticks were examined for the presence of A. phagocytophilum by PCR targeting the 16S rRNA. The seroprevalence against A. phagocytophilum was 17.03% and 11 horses (8.14%) showed positive PCR results. The concordance rate of A. phagocytophilum detection between IFAT and PCR had a K value of 0.34. 相似文献