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61.
The present work describes the microtomographic characterization of macro‐ and microcalcifications present in excised canine mammary glands. In human breast cancer, microcalcifications are highly relevant for diagnosis and prognosis, often being the sole element determining biopsy. Canine mammary tumours are considered a model for human breast cancer, but the morphological features of calcifications had still to be studied in this species. The objective of this research is to contribute to the characterization of the mineralization features of the canine mammary gland. In the present study, the excised mammary glands of 33 bitches underwent fluoroscopic examination. In 30 of the samples, the presence of calcification was suspected, and multiple biopsies were taken of these areas. Biopsy fragments underwent microtomographic scanning. Microcalcifications were found in non‐neoplastic glandular tissue, benign and malign lesions, as it is known to happen in humans. Qualitative evaluation regarding morphology of the imaged calcifications showed similarities to breast cancer findings, based on the BI‐RADS 2013 classification, such as pleomorphism and shape. No differences in the quantitative morphological parameters of volume, surface, surface/volume, SMI and structure thickness were found when macrocalcifications were considered. However, although significant differences existed in these parameters between microcalcifications from malignant canine mammary tumours and the two other groups, none were found between non‐neoplastic and benign tumours. Findings further support the use of this spontaneous animal model for the study of human breast cancer, considering how clinically relevant microcalcifications are in humans.  相似文献   
62.
Tropical Animal Health and Production - We aimed to evaluate the chemical composition, production yield, and economic viability of Minas Frescal cheese produced with milk from buffaloes...  相似文献   
63.
Nutritional and physiological significance of micronutrients in coffee plants, especially with regard to nickel (Ni) is still unknown. The dynamics of nitrogen (N), phosphorus (P), potassium (K) and Ni accumulation in coffee fruits, as well as their relationships with total soluble protein, amino acids, reducing sugars, and starch content during coffee fruit development (green, ripe, and dry fruits), were investigated. Coffee trees received three N fertilizer rates (0, 150, and 300 kg of N ha?1) as ammonium sulfate split into three applications per year. Nitrogen fertilization increased reducing sugars and starch concentrations in ripe fruits. In contrast, green fruits showed the highest amino acid and Ni concentrations. Fruit Ni concentration decreased in both green and ripe fruits as N rates increased; thus, indicating the possibility of either a N-associated dilution effect on Ni concentration or that Ni uptake by roots and/or transport to developing fruit was limiting. Plant nutritional status and fruit development stage influenced the coffee grain chemical composition. Furthermore, the variation in reducing sugars and starch content was more closely linked to the stage of fruit development than to N supply. A supposed relationship among the decreased of caffeine, starch, amino acids, and proteins with Ni content during green fruit development suggests a fundamental role for Ni in coffee fruit ripening. The interaction between N and Ni metabolism during fruit ripening might influence the chemical parameters involved in the coffee grain quality. This is the first report documenting changes in Ni concentrations of coffee fruit as a function of N fertilization rates and the development stage, but further research is needed to better understand the significance of N-Ni interaction in developing coffee fruit.  相似文献   
64.
In order to establish critical potassium (K) concentration levels and K/calcium (Ca) plus magnesium (Mg) [K/Ca+Mg] ratios in potato petioles associated to maximum total tuber yields, an experiment was conducted under Brazilian conditions. Six K levels (0, 60, 120, 240, 480, and 960 kg K2O/ha as potassium sulphate) were applied in a randomized complete block design experiment with four replications. Baraka potato tubers were seeded, spaced 0.8 x 0.3 m, following the agronomic cultural practices recommended for the crop. After 48 days from plant emergence, plant tissue samples was collected from each plant, the youngest fully expanded leaves (YFEL) and the oldest but not senescent leaves (ONSL). Petioles from these leaves were analysed to their K, Ca, and Mg contents. At harvest, total, high grade, and weight tuber yields were increased to 733, 719, and 660 g/plant for the 353, 335, and 384 kg K2O/ha levels, respectively. These yields are double the Brazilian potato yield average. Petiole Ca and Mg concentrations were decreased by the K fertilizer treatments, whereas the opposite occurred with the K/Ca+Mg ratio. Potassium concentrations in the petioles from the YFEL and ONSL increased up to 10.44 and 7.13 g K/100 g petiole dry matter at the 672 and 654 kg K2O/ha levels, respectively. The K petiole gradient concentration was not affected by K fertilization. The K/Ca+Mg ratio for YFEL associated with the maximum total tuber yield was 7.24, while the K concentrations were 8.91 and 6.16 g K/100 g dry matter in petioles for the YFEL and ONSL, respectively.  相似文献   
65.
In Brazil, sour rot is an important postharvest disease on fruits and vegetables. Geotrichum candidum (synonym Galactomyces candidus) has been reported as the main species causing this disease. However, the identity of the causal agent is still uncertain. This research aimed to determine the identity of 165 fungal isolates associated with sour rot obtained from fruits and vegetables in Brazil, and to evaluate the effect of different temperatures on the incidence of sour rot on artificially inoculated tomato fruits. Based on the phylogenetic analyses of DNA sequences from the D1/D2 domain of the large subunit (LSU) rRNA gene and morphological analyses, 129 samples belonged to Galactomyces candidus, 15 to G. candidum var. citri-aurantii, 6 to G. phurueaense, 2 to Gal. pseudocandidus, 1 to Hyphopichia burtonii, 1 to H. khmerensis, 3 to Saccharomycopsis crataegensis, 1 to S. vini, 1 to Magnusiomyces tetrasperma, 1 to Trichosporon coremiiforme, and 1 to Zygoascus meyerae. Two new species were found, namely, Geotrichum solani (on potato) and Geotrichum spondiadis (on red mombin). All isolates were pathogenic when inoculated on healthy tomato fruits, including the new species of Geotrichum, which were also inoculated into their respective hosts, that is, potatoes and red mombins. To the best of our knowledge, this study is the first to report the presence of five other genera besides Geotrichum associated with sour rot on fruits and vegetables in Brazil, which demonstrates the diversity of fungi and yeasts associated with this disease.  相似文献   
66.
European Journal of Plant Pathology - This study aimed to evaluate the potential antagonistic role of Trichoderma in the control of Fusarium isolates belonging to the Fusarium oxysporum species...  相似文献   
67.
Nicandra physaloides, a common weed in South America, was found to be infected by an isolate of Tomato severe rugose virus (ToSRV), a bipartite begomovirus. The plants developed severe yellow rugose mosaic and were collected in São Paulo State, Brazil. This isolate of ToSRV was transmitted by Bemisia tabaci B biotype from infected plants of N. physaloides to healthy plants of N. physaloides and tomato in a glasshouse. This is the first report of natural infection of N. physaloides by ToSRV in Brazil.  相似文献   
68.
In an attempt to obtain shelf-stable litchi fruit with preserved nutritional quality and good sensory features, quarters of peeled and pitted fruits were vacuum dried at 50, 60 and 70 °C at a constant pressure of 8.0 kPa. The product was assessed for its vitamin C, total phenolics and texture (hardness). In addition, the product with the best texture was assessed for its shelf-life by means of accelerated testing. Results suggest that vacuum dried litchi retained almost 70% of the vitamin C and total phenolics when compared to frozen fruits (control). Vitamin C and phenolic compounds content significantly decreased with drying, while no difference was found between different drying temperatures. Hardness increased with drying temperature. The sample dried at 70 °C presented crispness, which is a desired quality feature in dried fruit products. This sample was subjected to shelf-life evaluation, whose result suggests a shelf-life of eight months at 23 °C. Total color change (CIE ΔE00) was the expiry criterion. Vacuum drying was a suitable technique for producing shelf-stable litchi fruit with good texture while preserving its desirable original nutrients. Consumption of vacuum dried litchi may be beneficial to health due to its remarkable content of phenolic compounds and vitamin C.  相似文献   
69.
70.

The effect of mineral salts on water ingestion and urine volume in cattle has been extensively studied. However, recently, this effect has been investigated as a potential mitigator of environmental aspects related to the nitrogen (N) cycle, such as nitrate (NO3?) lixiviation, ammonia (NH3) volatilisation, and nitrous oxide (N2O) emissions. The effect of mineral salts, particularly sodium chloride (NaCl), on urine-N concentration, urine volume, the proportion of N compounds in the urine, and faecal-N concentration has not yet been explored in field conditions with respect to environmental aspects of beef cattle production. The present study investigated the effect of dietary mineral salt rates on these parameters. A Latin square (5?×?5) experimental design was utilised with five concentrations of mineral salts in the diet: 0.0, 2.0, 4.0, 6.0, and 8.0 g based on dry matter (DM) ingestion (g/kg DM). The nitrogen concentration in the urine and urine volume increased linearly. The total N excreted (g/day) via urine did not vary with increasing mineral salt concentrations. When evaluated, the N compounds of urine (urea-N, allantoin-N, and hippuric acid-N) also reacted to the increased mineral salt concentrations, while creatinine-N did not. Urea-N, allantoin-N, and hippuric acid-N linearly increased their proportions in total N-urine. The N concentration in faeces was not affected by mineral salt concentrations. The urine volume, concentration of N, and proportion of N compounds in the urine affected N2O emissions and NH3 volatilisation. Therefore, mineral salt utilisation may be an option for mitigating N pollution from beef cattle, especially for grasslands in tropical countries.

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