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61.
Lubica Pospíšilová Markéta Komínková Ondřej Zítka René Kizek Gabriela Barančíková Tadeáš Litavec 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(6):517-528
Composition of humic acids (HA) is a function of plant-derived inputs, degradation processes regulated by microorganisms, organo-mineral interactions and age. Characterization of different origin humic substances is important for evaluation of their contribution to stabile and labile carbon pool in the environment. The relative abundance of chemical components in HA isolated from soils, compost, commercial lignohumates, alginite, acadiane and lignite was studied with aim to quantify content of important biomarkers such as amino acid, lipids and polyphenols. HA were considered as a heterogeneous complex and high concentration of peptides, polyphenols and lipids was determined in acadian-HA to compare with soil-HA. Compost-HA contained much more amino acids to compare with soil-HA samples. Alginite-HA and lignite-HA were similar in biomarkers content to soil-HA. Fourier transform infrared spectroscopy confirmed that chemical composition and functional groups content differs with the origin, humification degree and the age of studied samples. Soil-HA are typically composed of a variety of ?OH, COOH?, C–O, C–H2, (aliphatic and aromatic) groups, quinines, lignin fragments, polysaccharide, monosaccharide and proteins fragments, which are linked together by ?O?, ?NH?, ?H=, >C=O, metal ions and –S? groups. 13C NMR spectroscopy showed that aromatic carbon content was the highest in lignite-HA and soil-HA. 相似文献
62.
Maria Montseny Cristina Linares Núria Viladrich Pol Capdevila Stefano Ambroso David Díaz Josep‐Maria Gili Andrea Gori 《水产资源保护:海洋与淡水生态系统》2020,30(5):977-987
- Gorgonians dwelling on the Mediterranean continental shelf are among the most frequent fishing bycatch taxa. These species display several traits, such as long lifespans and slow growth, which make them very vulnerable to the impacts caused by fishing activities with far‐reaching and long‐lasting effects.
- Hence, restoration and mitigation actions are crucial to enhance and speed up the natural recovery of damaged cold‐water coral gardens. Given the growing concern to develop effective and affordable restoration actions, the present study aims to propose and technically validate a new large‐scale and cost‐effective restoration method.
- This technique, named ‘badminton method', consists of attaching bycatch Eunicella cavolini colonies to cobble supports and returning them to the continental shelf by gently throwing the gorgonian transplants directly from a boat.
- Two consecutive field experiments were conducted in order to find the best cobble type support and gorgonian size to be used: first, to evaluate the landing efficiency of gorgonian transplants at different depths (from 5 to 30 m) and second, to evaluate their capability to maintain a correct position over time.
- Natural cobbles with large gorgonians attached were the best option. Field results and modelling approaches suggest that the transplants would correctly land on the continental shelf seabed in a predicted area of around 60 m2. Moreover, they would successfully maintain an upright position ensuring gorgonian survival over time.
- The success of this method highlights the feasibility of large‐scale and low‐cost restoration actions with promising results for the conservation and recovery of cold‐water coral gardens.
63.
COMBINATION OF RADIATION THERAPY AND FIROCOXIB FOR THE TREATMENT OF CANINE NASAL CARCINOMA 下载免费PDF全文
Simona Cancedda Silvia Sabattini Giuliano Bettini Vito F. Leone Paola Laganga Federica Rossi Rossella Terragni Giacomo Gnudi Massimo Vignoli 《Veterinary radiology & ultrasound》2015,56(3):335-343
Carcinomas represent two‐thirds of canine nasosinal neoplasms. Although radiation therapy (RT) is the standard of care, the incidence of local recurrence following treatment is high. Cyclooxygenase‐isoform‐2 (COX‐2) is expressed in 71–95% of canine nasal carcinomas and has been implicated in tumor growth and angiogenesis. Accordingly, COX‐2 inhibition seems rational to improve outcome. Dogs with histologically confirmed, previously untreated nasal carcinomas were randomized to receive the combination of a selective COX‐2 inhibitor (firocoxib) and palliative RT (Group 1) or RT and placebo (Group 2). Patients were regularly monitored with blood tests, urinalysis, and computed tomography. Pet owners were asked to complete monthly a quality‐of‐life questionnaire. Twenty‐four dogs were prospectively enrolled. According to Adams modified system, there were five stage 1, five stage 2, three stage 3, and 11 stage 4 tumors. Two dogs had metastases to regional lymph nodes. Median progression‐free interval and overall survival were 228 and 335 days in Group 1 (n = 12) and 234 and 244 days in Group 2 (n = 12). These differences were not statistically significant. The involvement of regional lymph nodes was significantly associated with progression‐free interval and overall survival (P = 0.004). Quality of life was significantly improved in Group 1 (P = 0.008). In particular, a significant difference was observed for activity and appetite. Although not providing a significant enhancement of progression‐free interval and overall survival, firocoxib in combination with RT is safe and improved life quality in dogs with nasal carcinomas. 相似文献
64.
This study investigates the optimal conditions for the vegetative propagation of the multipurpose leguminous shrub Colutea istria from leafy stem cuttings. The conditions examined included 1) the origin of the cutting (apical, medial or basal), 2) indole-3-butyric
acid (IBA) treatment (0, 50, 200 or 400 mg/l), 3) the relative humidity of the propagation environment (high or low), 4) wounding
base of cutting, and 5) the season in which the cutting was taken. The rooting ability of the cuttings was significantly influenced
by all these factors. Winter cuttings obtained from the middle and base of the branch showed a greater rooting capacity than
those harvested from the apical area, while autumn cuttings harvested from the middle and apical areas of the branch showed
a greater rooting capacity than those harvested from the base. Winter cuttings showed the best rooting capacity than autumn
cuttings. IBA treatment (200 mg/l), high humidity (98-100%), and wounding increased the rooting capacity of the cuttings. The sprout
of new leaves was higher in basal cuttings, while IBA and wounding also significantly enhanced the root number of rooted cuttings.
A method for vegetatively propagating C. istria plants is given. 相似文献
65.
66.
Ojeda-Robertos Nadia Florencia Torres-Chablé Oswaldo Margarito Peralta-Torres Jorge Alonso Luna-Palomera Carlos Aguilar-Cabrales Aguilar Chay-Canul Alfonso Juventino González-Garduño Roberto Machain-Williams Carlos Cámara-Sarmiento Ramón 《Tropical animal health and production》2017,49(3):613-618
Tropical Animal Health and Production - The objective was to determine the frequency of gastrointestinal parasites (GP) genera affecting water buffalo (Bubalus bubalis) reared under humid tropical... 相似文献
67.
68.
Hashizume T Shida R Suzuki S Nonaka S Yonezawa C Yamashita T Kasuya E Sutoh M Oláh M Székács D Nagy GM 《Domestic animal endocrinology》2008,34(2):146-152
The aims of the present study were to determine whether salsolinol (SAL), a dopamine-related compound, is present in the bovine posterior pituitary (PP) gland, and to clarify the effect of SAL on the secretion of prolactin (PRL) in ruminants. SAL was detected in extract of bovine PP gland using high-pressure liquid chromatography with electrochemical detection (HPLC-EC). A single intravenous (i.v.) injection of SAL (5 and 10mg/kg body weight) significantly and dose-dependently stimulated the release of PRL in goats (P<0.05). Plasma PRL levels reached a peak 10min after the injection, then gradually returned to basal values in 60-80min. The PRL-releasing pattern was similar to that in response to sulpiride (a dopamine receptor antagonist). The intracerebroventricular (i.c.v.) injection of 1mg of SAL had no significant effect on the release of PRL in calves, however, 5mg significantly stimulated the release (P<0.05) with peak values reached 30-40min after the injection. Moreover, SAL significantly stimulated the release of PRL from cultured bovine anterior pituitary cells at doses of 10(-6) and 10(-5)M, compared to control cells (P<0.05). Taken together, our data clearly show that SAL is present in extract of the PP gland of ruminants, and has PRL-releasing activity both in vivo and in vitro. Therefore, this endogenous compound is a strong candidate for the factor having PRL-releasing activity that has been previously detected in extract of the bovine PP gland. 相似文献
69.
Magnetic Resonance Imaging of the Normal Canine Larynx 总被引:1,自引:0,他引:1
J. M. Vázquez A. Arencibia F. Gil J. A. Ramírez N. González C. D. Sosa J. R. Jaber 《Anatomia, histologia, embryologia》1998,27(4):263-270
The purpose of this study was to define the normal anatomic structures in the canine larynx with magnetic resonance images. TI-weighted images were taken in the sagittal and transverse planes. The MR images were obtained comparing MR images to dissection planes. Magnetic resonance imaging provides excellent anatomic detail of laryngeal structures. Therefore, it is of value for diagnostic imaging of some respiratory diseases in the dog. 相似文献
70.
Körner C Asshoff R Bignucolo O Hättenschwiler S Keel SG Peláez-Riedl S Pepin S Siegwolf RT Zotz G 《Science (New York, N.Y.)》2005,309(5739):1360-1362
Whether rising atmospheric carbon dioxide (CO2) concentrations will cause forests to grow faster and store more carbon is an open question. Using free air CO2 release in combination with a canopy crane, we found an immediate and sustained enhancement of carbon flux through 35-meter-tall temperate forest trees when exposed to elevated CO2. However, there was no overall stimulation in stem growth and leaf litter production after 4 years. Photosynthetic capacity was not reduced, leaf chemistry changes were minor, and tree species differed in their responses. Although growing vigorously, these trees did not accrete more biomass carbon in stems in response to elevated CO2, thus challenging projections of growth responses derived from tests with smaller trees. 相似文献