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排序方式: 共有606条查询结果,搜索用时 15 毫秒
191.
Alessandro Ianiro Matteo Di Giosia Simona Fermani Chiara Samorì Marianna Barbalinardo Francesco Valle Graziella Pellegrini Fabio Biscarini Francesco Zerbetto Matteo Calvaresi Giuseppe Falini 《Marine drugs》2014,12(12):5979-5992
The squid pen (gladius) from the Loligo vulgaris was used for preparation of β-chitin materials characterized by different chemical, micro- and nano-structural properties that preserved, almost completely the macrostructural and the mechanical ones. The β-chitin materials obtained by alkaline treatment showed porosity, wettability and swelling that are a function of the duration of the treatment. Microscopic, spectroscopic and synchrotron X-ray diffraction techniques showed that the chemical environment of the N-acetyl groups of the β-chitin chains changes after the thermal alkaline treatment. As a consequence, the crystalline packing of the β-chitin is modified, due to the intercalation of water molecules between β-chitin sheets. Potential applications of these β-chitin materials range from the nanotechnology to the regenerative medicine. The use of gladii, which are waste products of the fishing industry, has also important environmental implications. 相似文献
192.
Cringoli G Otranto D Testini G Buono V Di Giulio G Traversa D Lia R Rinaldi L Veneziano V Puccini V 《Veterinary research》2002,33(4):421-428
This investigation was carried out in an area covering part of three southern Italian regions: Campania, Basilicata and Apulia. Eighty-one farms were involved using the formula suggested by Thrusfield; they were equally distributed over the area which was subdivided into 81 geo-referenced sub-areas. In May and June 1999 from a total of 506 cattle, older than 18 months, blood-samples were taken and ticks were collected and identified. Serum samples were tested for antibodies of Bahesia bigemina, Babesia bovis and Anaplasma marginale with an ELISA technique. Eight farms (9.8%) out of the 81 examined were positive for B. bigemina only, 3 (3.7%) for A. marginale only, and 70 (86.4%) for both. None of the animals of any farm was found to be positive for B. bovis. Out of the 506 sera tested, 117 (23.1 %) were positive for B. bigemina only, 58 (11.5%) forA. marginale only and 250 (49.4%) for both species; 81 (16.0%) were negative for all of them. Ticks were collected on animals on 62 (76.5%) out of the 81 farms. Adult ticks (1 410) were collected and identified; the highest number belonged to the Rhipicephalus bursa species (65.5%), followed by Rhipicephalus turanicus (8.6) and Haemaphysalis punctata (8.4). The results showed that B. bigemina, A. marginale and their potential vectors are common in the area examined and indicated that there is a risk for animals imported from tick-borne disease-free areas. 相似文献
193.
Giuseppe Lima Filippo De Curtis Raffaello Castoria Vincenzo De Cicco 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(4):341-349
The biocontrol yeast isolates Rhodotorula glutinis LS11, Cryptococcus laurentii LS28 and Aureobasidium pullulans LS30 were tested against Botrytis cinerea and Penicillium expansum on apples artificially inoculated and stored at 3 and 20 °C. Isolates LS28 and LS30 were most effective, consistently resulting in high reductions of fungal decay, while isolate LS11 was effective only on apples stored at 3 °C. The yeasts showed good in vitro resistance to dicarboximides and copper fungicides, while they were inhibited by triazoles. Isolate LS11, in contrast to LS28 and LS30, was also inhibited by benzimidazoles. The yeasts were tested on naturally-infected apples in semi-commercial conditions for 2 years. They were applied twice: soon after harvesting and 20 days later, at the beginning of the cold storage. The antagonists significantly reduced fungal decay when combined with a low dosage of benomyl showing an activity comparable to that exerted by the fungicide alone at full dosage. Periodical monitoring of the epiphytic biocontrol yeast populations in both the field and cold room showed a good rate of survival of the antagonists on the skin of treated apples. Specific fingerprints relying on amplified restriction length polymorphism (AFLP) were used to integrate the morphology-based monitoring of the yeasts. 相似文献
194.
Traversa D Avolio S Modrý D Otranto D Iorio R Aroch I Cringoli G Milillo P Albrechtová K Mihalca AD Lavy E 《Veterinary parasitology》2008,157(1-2):108-116
Spirocerca lupi (Nematoda, Spirurida) is a life-threatening parasitic nematode of dogs that is presently emerging in several countries. Nonetheless, canine spirocercosis is neglected and underestimated, mainly due to diagnostic limitations inherent to clinico-pathologic, diagnostic imaging and laboratory methodologies. Given the significant benefit of improved diagnosis, the present work evaluated the reliability of a recently described copromicroscopic approach, the FLOTAC technique, as well as a PCR-based assay with that of traditional coproscopic techniques to diagnose S. lupi infection. Ninety-four faecal field samples were collected from two endemic areas (i.e. 29 and 65 from Kenya and Israel, respectively) and processed using different coproscopic examination techniques. In particular, set I (Kenyan samples) comprised the modified flotation with Sheather's sugar solution and merthiolate-iodine-formalin technique, while set II (Israeli samples) comprised a flotation technique with zinc sulphate solution, a modified sugar flotation procedure and the FLOTAC method. All samples were also subjected to a semi-nested PCR protocol specific for a region internal to the mitochondrial cytochrome c oxidase subunit 1 gene of S. lupi. The coproscopic examinations showed low sensitivity and high variability, demonstrating the unreliability of the conventional methods for detecting S. lupi eggs. Nonetheless, the FLOTAC technique scored the highest number of positives and significantly higher number of S. lupi eggs per microscopic field compared to the other coproscopic methods. Additionally, of the coproscopically negative samples, 9 (45%) Kenyan and 21 (38.2%) Israeli samples scored molecularly positive using the PCR-based approach. The potential implications and perspectives for canine spirocercosis of these coproscopic and molecular diagnostic methodologies evaluated herein are discussed. 相似文献
195.
196.
Massimo Vignoli DVM SRV Federica Rossi DVM SRV Giuseppe Sarli DVM 《Veterinary radiology & ultrasound》1999,40(2):116-119
A 7-year-old neutered female domestic short hair cat was presented with hind limb ataxia. A subarachnoid cyst in the T10-T11 spinal cord region was identified by myelography as a collection of contrast medium in the subarachnoid space. 相似文献
197.
Emanuele Marconi Maria Cristina Messia Giuseppe Palleschi Raimondo Cubadda 《Cereal Chemistry》2004,81(1):6-9
A reliable method for the quantitative determination of gelatinized starch in processed cereal foods was developed. It consists of an electrochemical biosensor based on amyloglucosidase and glucose oxidase enzymes co‐immobilized on a Pt electrode surface, and a third enzyme, α‐amylase, added in solution. Analytical parameters such as time, temperature, and enzyme units were optimized. The degree of starch gelatinization was determined in different processed cereal foods using the biosensor method and the results were commensurate to those obtained with the reference method. The biosensor methods showed good accuracy (r2 = 0.9629; relative error <12%) and comparable precision (RSD <5%). This electrochemical system is rapid, reliable, inexpensive, user‐friendly for unskilled operators, and can be a valid alternative to the methods traditionally used for gelatinized starch analysis. 相似文献
198.
199.
Giuseppe Sarli Rosario Preziosi Cinzia Benazzi Roberta Bazzo Luciana Mandrioli Paolo Stefano Marcato 《Journal of veterinary diagnostic investigation》2003,15(2):115-122
Invasion, cell proliferation and apoptosis are important biological features of neoplasia, bearing prognostic importance. Histological stage, mitotic index, and apoptotic index have been assessed in 33 feline malignant mammary tumors. Histological stage (P < 0.01) and mitotic index (P < 0.001) had a significant association with prognosis in univariate analysis. Apoptotic index did not correlate with survival (P = 0.44), and histological stage (P = 0.48) did not correlate with mitotic index (P = 0.39). In feline malignant mammary tumors the apoptotic index seems unable to predict survival and lacks any correlation with proliferation assessed as mitotic index. A possible explanation for the lack of correlation between apoptotic index and survival may be due to the rapid acquisition of pathways of apoptosis resistance in feline mammary tumors or to rapid hormone receptors loss. 相似文献
200.
Porcine circovirus type 2 detection in in vitro produced porcine blastocysts after virus sperm exposure 下载免费PDF全文
Giovanna Galeati Augusta Zannoni Marcella Spinaci Diego Bucci Fabio Ostanello Serena Panarese Carlo Tamanini Giuseppe Sarli 《Animal Science Journal》2016,87(4):511-516
This study was aimed at assessing the capability of semen experimentally infected with porcine circovirus type 2 (PCV2) to produce porcine blastocysts PCR positive for PCV2. Embryos were obtained from in vitro maturation (IVM) and in vitro fertilization (IVF) of porcine oocytes or by parthenogenesis. Sperm suspension was exposed to PCV2b and utilized for IVF. PCV2 spiked semen did not reveal any reduction in sperm viability or motility but its ability to produce infected blastocysts was irrelevant as only one out of 15 blastocysts obtained by IVF were PCV2b; however two blastocysts were PCV2a positive. Furthermore, the presence of PCV2 was demonstrated also in embryos obtained by parthenogenesis (one out of 17 was PCV2b and one PCV2a positive). Even if PCV2 firmly attaches to the surface of spermatozoa, experimentally spiked sperm were not effective in infecting oocytes during IVF and in producing PCR positive embryos. The infected blastocysts we obtained derived most probably from infected oocytes recovered at the abattoir. 相似文献