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851.
CASE SUMMARY: A 12.5-year-old castrated male domestic shorthair cat was presented for evaluation of dyspnea. Physical examination suggested upper airway disease. Computed tomography revealed the presence of a nasopharyngeal mass. Biopsies obtained via rhinoscopy led to a diagnosis of olfactory neuroblastoma. CLINICAL CHALLENGES: Olfactory neuroblastoma (or esthesioneuroblastoma) is a rare malignant neoplasm that arises from olfactory neuroepithelium. It was first described in human medicine in 1924. Clinical signs are variable, and diagnosis may prove challenging as this tumor, which is a differential for spontaneous intranasal tumors in cats, may be mistaken for poorly differentiated carcinomas or round cell tumors. Given its rarity, treatment options for this neoplasm have not been thoroughly evaluated and there is no standard treatment protocol. LITERATURE REVIEW: A review of veterinary and human literature is provided, encompassing clinical signs, staging and grading systems, treatment options and prognostic factors. 相似文献
852.
Nitrate-nonutilizing (nit) mutants were recovered for the first time from 21 isolates of Sclerotinia homoeocarpa collected in the United States. Mutants were selected from shredded mycelium of each isolate when cultured on water agar medium amended with 4% (wt/vol) potassium chlorate. The mutants could be classified into three phenotypes: nit1, nit3, and NitM, based on their growth on minimal medium (Czapek solution agar) supplemented with NaNO(2) or hypoxanthine. Complementary heterokaryons were observed in pairings between different phenotypes of nit mutants derived from compatible isolates, but not in self-fusions or pairings between incompatible isolates. The vigor of prototrophic growth varied with isolates and mutant phenotypes. Strong and continuous heterokaryons, as well as weak and spontaneous ones, formed depending on pairings of nit mutants. Stable heterokaryons between compatible isolates, but apoptotic reactions between incompatible isolates, were observed immediately after hyphal fusion under the epifluorescence microscope. The 21 isolates used in this study, which were previously assigned into 11 different vegetative compatibility groups (VCGs) based on the formation of a barrage zone at the contact site of paired isolates on complete medium (potato dextrose agar), were regrouped into five VCGs based on heterokaryon formation between nit mutants on minimal medium. 相似文献
853.
Bruna Arruda Daniel João Dall’orsoletta Joice Crescencio Heidemann Luciano Colpo Gatiboni 《Archives of Agronomy and Soil Science》2018,64(7):1011-1020
Soil organic matter (SOM) is a key of most nutrient cycling and its content influences labile phosphorus (P) pool. In order to promote P availability from SOM, some plant strategies could be important to increase organic P mineralization, which may change among cultivars of the same crop. This study evaluated phosphorus dynamics in the rhizosphere of two wheat cultivars in soil with high organic matter content. Experiment was established in a greenhouse using a Humic Cambisol in a randomized block design using Quartzo and Abalone as wheat cultivars and harvested 20 days after seedling. Pots with a horizontal mesh (25 µm) were used to isolate the soil from roots. At harvest, the soil under the mesh was sliced in five distances from the rhizoplane (0–3; 3–6; 6–10; 10–20; 20–30 mm). Organic P was the buffer to maintain P dynamics in the rhizosphere and there was phosphorus depletion in the first slice near the rhizoplane due to the root effect, regardless the cultivar. Quartzo showed high labile inorganic P, presumably due to the high amount of root hairs, which increased the acid phosphatase activity and consequently root P uptake. Quartzo was more efficient in changing rhizosphere regarding the P acquisition. 相似文献
854.
Hampered cumulus expansion of porcine cumulus‐oocyte complexes by excessive presence of alpha2‐macroglobulin is likely mediated via inhibition of zinc‐dependent metalloproteases 下载免费PDF全文
Ruth Appeltant Dominiek Maes Jo Bijttebier Katleen Van Steendam Hans Nauwynck Ann Van Soom 《Animal Science Journal》2017,88(9):1279-1290
In vitro maturation (IVM) in serum causes hampered expansion of porcine cumulus‐oocyte complexes (COCs) due to excessive alpha2‐macroglobulin (A2M). This study investigated two hypotheses that could explain the effect of A2M: (i) binding of epidermal growth factor (EGF) to A2M, followed by its decreased availability; and (ii) inhibition of zinc‐dependent metalloproteases. Cumulus expansion was evaluated based on the diameter of the COCs, the proportion of COCs participating in a floating cloud and the proportion of COCs with loss of cumulus cells. The first hypothesis of decreased EGF availability was tested by increasing the EGF concentration (20 and 50 ng/mL vs. 10 ng/mL), but was not confirmed because cumulus expansion did not improve. To verify the second hypothesis of inhibited zinc‐dependent metalloproteases, the effect of tissue inhibitor of metalloproteases‐3 (TIMP‐3) on cumulus expansion during IVM with and without A2M was investigated. To immuno‐neutralize A2M, serum was pre‐incubated with A2M antibodies. Impaired cumulus expansion because of TIMP‐3 could only be observed during IVM in 10% of serum with A2M antibodies. No effect of TIMP‐3 was observed in medium without A2M antibodies. These results indicate that A2M and TIMP‐3 share a common target, a zinc‐dependent metalloprotease. Future research is directed toward the identification of the protease involved. 相似文献
855.
856.
Kamila Câmara Correia João Victor Jansen de Queiroz Ricardo Brainer Martins Alessandro Nicoli Emerson Medeiros Del Ponte Sami Jorge Michereff 《European journal of plant pathology / European Foundation for Plant Pathology》2017,149(2):269-276
A standard area diagram set (SADs) with eight severity values ranging from 0.5 to 32% was evaluated as a tool to improve the accuracy of the estimates of Phomopsis leaf blight severity on eggplant by ten inexperienced raters. A first assessment in a 50-leaf dataset of digital images was performed unaided (UN, no SAD). Two further aided (A) assessments, conducted two (A1) and four weeks after the first (A2) unaided one were performed. The precision of the estimates, as indicated by the Pearson’s correlation coefficient (r), improved significantly when using the aid (A1: r = 0.96 and A2: r = 0.96) compared to unaided (UN: r = 0.79). However, the generalized bias (C b) was not significantly affected because the unaided estimates were already quite accurate (C b = 0.93). The overall concordance (ρ c) was significantly improved due to the large gains in precision when using the SADs. The raters’ estimates were more uniform (ρ c > 0.9) when using the aid, with progressive gains in the reliability of the estimates among them, indicated by the concordance correlation coefficient statistics. The SADs proposed in this study will be useful in severity estimation during field work involving multiple raters, especially as use of the SADs results in less variable estimates, improving accuracy and reliability among raters. 相似文献
857.
Oscar F Santos‐Amaya Clébson S Tavares João Victor C Rodrigues Silverio O Campos Raul Narciso C Guedes Analiza P Alves Eliseu José G Pereira 《Pest management science》2017,73(1):i-i
The cover image, by Oscar Fernando Santos‐Amaya et al., is based on the Research Article Fitness costs and stability of Cry1Fa resistance in Brazilian populations of Spodoptera frugiperda, DOI: 10.1002/ps.4312 . Photo Credit: Dr. Oscar Santos‐Amaya.
858.
João Paulo Gonsiorkiewicz Rigon Juliano Carlos Calonego Tiara Moraes Guimarães Ciro Antonio Rosolem 《Communications in Soil Science and Plant Analysis》2017,48(14):1726-1732
It is convenient to store gas samples containing e.g. carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), in polypropylene syringes before chromatographic analysis. However, there is no study of the integrity of these samples or of what storage condition may be critical. To investigate we filled polypropylene syringes with two standard mixtures of CO2, CH4, and N2O, and stored them at ~2 °C and ~25 °C, and analyzed the contents using gas chromatography. Our results suggest that the storage of gases on the syringe at room temperature is not viable due the CO2 storage integrity when in low concentration. However, the quantitative integrity of samples is maintained when the syringe is kept refrigerated up to 19 h, period limited by CO2 and CH4, taking into account the three gases CO2, CH4, and N2O. 相似文献
859.