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排序方式: 共有129条查询结果,搜索用时 31 毫秒
91.
Brunello Ceccanti Serena Doni Cristina Macci Giovanni Cercignani Grazia Masciandaro 《Soil biology & biochemistry》2008,40(9):2174-2177
Conventional parameters (total organic carbon, total nitrogen, humic acids and fulvic acids) frequently associated with soil quality were measured and compared with the amount and activity of β-glucosidases associated with the humic–enzyme complex. Soil quality may be defined as the maintenance of an “enzymatically active humic carbon pool” which may express soil resilience and ecological functions. The combination of ultrafiltration (UF) and isoelectric focussing (IEF) permitted the extraction and purification of the humic-bound β-glucosidases. Even though humic-β-glucosidases represent only a small part of soil humic matter either in terms of total soil β-glucosidase activity (3–21%) or as a proportion of the humic-C content (4–8%), they proved to be discriminating parameters (significative differences at P < 0.05) for defining soil biochemical quality. Specifically, on the basis of the amount of β-glucosidase activity in the humic fraction >104 Da (IEF peaks in the pH range 3.5–4.5), the soils were distributed in a decreasing order of quality: undisturbed meadow > tree plantation > 60-year vineyard > agricultural soil > 1-year vineyard. 相似文献
92.
Luciano Telesca Rosa Caggiano Vincenzo Lapenna Michele Lovallo Serena Trippetta Maria Macchiato 《Water, air, and soil pollution》2009,201(1-4):33-41
The Fisher–Shannon information plane (FS), defined by the Fisher information measure and the Shannon entropy power, is proposed to investigate the complex dynamics of the concentration of three heavy metals (Cd, Fe, and Pb) in four different fractions of particulate matter data, recorded in Tito, a small industrial area of southern Italy. In the FS plane, the three metals are aggregated in three different clusters, characterized by different degrees of order. This result is related to different sources of the three metals. 相似文献
93.
An 8‐year‐old Gypsy Vanner gelding presented to the University of Florida Ophthalmology service for the evaluation of chronic, recurrent corneal ulcers behind the third eyelid of the right eye. On ophthalmic examination, a cluster of aberrant hairs was identified growing along the margin of the third eyelid. This portion of third eyelid was surgically excised, and histopathology identified the haired tissue as a dermoid. Chronic keratitis secondary to a third eyelid dermoid was diagnosed, and excision appeared curative at 6 months post‐operative follow‐up. 相似文献
94.
D Singh JM Chan P Zoppoli F Niola R Sullivan A Castano EM Liu J Reichel P Porrati S Pellegatta K Qiu Z Gao M Ceccarelli R Riccardi DJ Brat A Guha K Aldape JG Golfinos D Zagzag T Mikkelsen G Finocchiaro A Lasorella R Rabadan A Iavarone 《Science (New York, N.Y.)》2012,337(6099):1231-1235
The brain tumor glioblastoma multiforme (GBM) is among the most lethal forms of human cancer. Here, we report that a small subset of GBMs (3.1%; 3 of 97 tumors examined) harbors oncogenic chromosomal translocations that fuse in-frame the tyrosine kinase coding domains of fibroblast growth factor receptor (FGFR) genes (FGFR1 or FGFR3) to the transforming acidic coiled-coil (TACC) coding domains of TACC1 or TACC3, respectively. The FGFR-TACC fusion protein displays oncogenic activity when introduced into astrocytes or stereotactically transduced in the mouse brain. The fusion protein, which localizes to mitotic spindle poles, has constitutive kinase activity and induces mitotic and chromosomal segregation defects and triggers aneuploidy. Inhibition of FGFR kinase corrects the aneuploidy, and oral administration of an FGFR inhibitor prolongs survival of mice harboring intracranial FGFR3-TACC3-initiated glioma. FGFR-TACC fusions could potentially identify a subset of GBM patients who would benefit from targeted FGFR kinase inhibition. 相似文献
95.
Giuseppe Sarli Federico Morandi Serena Panarese Barbara Bacci Domenico Ferrara Carlo Bianco Laura Fusaro Maria Laura Bacci Giovanna Galeati Michele Dottori Paolo Bonilauri Davide Lelli Giorgio Leotti Thais Vila Francois Joisel Gordon Allan Cinzia Benazzi Fabio Ostanello 《Acta veterinaria Scandinavica》2012,54(1):51
Background
Since 1999, field evidence of transplacental infection by porcine circovirus type 2 (PCV2) and reproductive failure has been reported in pigs. The objective of this study was to evaluate the clinical and pathological consequences of PCV2 infection in conventional PCV2-seropositive gilts by insemination with PCV2b-spiked semen.Results
Six PCV2 seropositive gilts were inseminated with PCV2b-supplemented semen (infected) and three animals with semen and cell culture medium (controls). Only three out of the six infected animals were pregnant by ultrasonography on day 29 after insemination, while two out of the three controls were pregnant. One control gilt aborted on day 23 after insemination but not due to PVC2. Viraemia was demonstrated in four out of six infected and in one control gilt that became infected with PCV2a. Anti-PCV2 antibody titres showed dynamic variations in the infected group throughout the study. Among infected gilts, the animal with the lowest anti-PCV2 titre (1/100) at the beginning of the experiment and another that reached a similar low value during the experiment showed evident seroconversion over time and had also PCV2 positive foetuses. One placenta displayed mild focal necrosis of the chorionic epithelium positively stained by immunohistochemistry for PCV2 antigen.Conclusions
PCV2-seropositive gilts can be infected with PCV2 after intrauterine exposure and low maternal antibody titre may increase the probability of a foetal infection. 相似文献96.
97.
Vizza E Correr S Barberini F Heyn R Bianchi S Macchiarelli G 《The Journal of reproduction and development》2005,51(4):433-443
In order to understand the 3-D distribution of collagen in relation to vascularization, chorionic villi of human placentae, belonging to normal pregnancies at term, were studied by scanning electron microscopy (SEM) after alkali maceration techniques, and by transmission electron microscopy (TEM). The villous tree appeared made of an uninterrupted structure of collagen fibres. The collagen fibres connected the chorionic villi axis with their basal plates and organised differently according to the various levels of villous branching. The collagen of stem villi showed copious fibres. The external fibres (facing the villous surface) were arranged mainly longitudinally. The central core of the villi (inner fibres) were arranged concentrically around the wall of the fetal vessels. Both external and internal fibres formed stratified lamellae or small parallel bundles. The inner core of stem villi showed small holes housing capillary spaces. Mature intermediate and terminal villi showed a scarce amount of collagen arranged in thin concentric layer within the villous core, surrounding numerous dilated capillary and sinusoid spaces.These observations demonstrated that the extracellular matrix of human chorionic villi is highly compartmentalised and shows a variable structural 3-D distribution depending on the branching level of the villous tree, such a distribution ensures the most favourable microenvironment for feto-maternal exchanges and it is likely able to provide a modulated support to the developing chorionic fetal vessels and trophoblastic layer as well. 相似文献
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100.
Martina Falagiarda Veronica Carnio Serena Giorgia Chiesa Antonio Pignalosa Gianfranco Anfora Gino Angeli Claudio Ioriatti Valerio Mazzoni Silvia Schmidt Livia Zapponi 《Pest management science》2023,79(7):2397-2414