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排序方式： 共有591条查询结果，搜索用时 31 毫秒
71.
Kovacevic Branislav Roncevic Savo Miladinovic Dragana Ivanisevic Petar Katanic Marina 《New Forests》2009,38(2):177-185
The relationship between early root and shoot formation at the beginning of the vegetation period and cutting survival on
sandy and loamy fluvisol for 14 genotypes of black poplars was analyzed. Considerable cutting mortality was observed only
within the first 80 days since planting. Intensive root formation in the first 20 days since the planting and vigorous shoot
growth and development in subsequent 20 days was observed in easy-to-root genotypes. Coefficients of correlation revealed
close relationship between early root and shoot growth and development and cutting survival of tested genotypes. The obtained
results could be used in the breeding process, as well as for the design of cultivar-adjusted nursery and plantation establishment
technology. Tested shoot characteristics, were found to be especially interesting since they could be measured rapidly, by
non-destructive means. 相似文献
72.
A new iridoid diglucoside, 10-O-(E)-p-coumaroylmelittoside (1) and a new flavone glucoside, O-(6'-O-Acetyl-)-beta-glucopyranosylchrysoeriol (2), together with four known flavone glycosides, were isolated from the aerial parts of Sideritis lanata. The structures of the new compounds were elucidated by spectroscopic methods, 2D NMR and MS. 相似文献
73.
The mechanical properties and responses of cells to external stimuli (including drugs) are closely connected to important phenomena such as cell spreading, motility, activity, and potentially even differentiation. Here, reversible changes in the viscoelastic properties of surface-attached fibroblasts were induced by the cytoskeleton-perturbing agent cytochalasin D, and studied in real-time by the quartz crystal microbalance with dissipation (QCM-D) technique. QCM-D is a surface sensitive technique that measures changes in (dynamically coupled) mass and viscoelastic properties close to the sensor surface, within a distance into the cell that is usually only a fraction of its size. In this work, QCM-D was combined with light microscopy to study in situ cell attachment and spreading. Overtone-dependent changes of the QCM-D responses (frequency and dissipation shifts) were first recorded, as fibroblast cells attached to protein-coated sensors in a window equipped flow module. Then, as the cell layer had stabilised, morphological changes were induced in the cells by injecting cytochalasin D. This caused changes in the QCM-D signals that were reversible in the sense that they disappeared upon removal of cytochalasin D. These results are compared to other cell QCM-D studies. Our results stress the combination of QCM-D and light microscopy to help interpret QCM-D results obtained in cell assays and thus suggests a direction to develop the QCM-D technique as an even more useful tool for real-time cell studies. 相似文献
74.
75.
Marina L. Leis M. Elyse Salpeter Bianca S. Bauer Dale L. Godson Bruce H. Grahn 《Veterinary ophthalmology》2017,20(4):365-371
A 15‐year‐old, neutered male, Shih Tzu cross developed progressive corneal stromal thickening and vascularization of the right eye, and 5 months later, of the left eye. Both eyes became blind due to extensive corneal opacification and were enucleated. Light microscopic examination revealed a diffuse corneal infiltrate of neoplastic mesenchymal cells, and immunohistochemistry revealed diffuse cytoplasmic vimentin immunoreactivity and variable cytoplasmic and nuclear immunoreactivity for S100 in the neoplastic cells. Transmission electron microscopy revealed desmosomes between contiguous cells, thread‐like cytoplasmic processes coated with basement membrane, extracellular bundles of collagen, and axonal degeneration consistent with features of a nerve sheath neoplasm. This is the first report of primary, bilateral corneal nerve sheath sarcoma in a canine. 相似文献
76.
Graeme M. Doodnaught Marina C. Evangelista Paulo V.M. Steagall 《Veterinary anaesthesia and analgesia》2017,44(2):364-369
Objective
To evaluate the onset, magnitude and duration of thermal antinociception after oral administration of two doses of tapentadol in cats.Study design
Prospective, randomized, blinded, experimental study.Animals
Six healthy adult cats weighing 4.4 ± 0.4 kg.Methods
Skin temperature (ST) and thermal threshold (TT) were evaluated using a wireless TT device up to 12 hours after treatment. Treatments included placebo (PBO, 50 mg dextrose anhydrase orally), buprenorphine (BUP, 0.02 mg kg?1) administered intramuscularly, low-dose tapentadol (LowTAP, 25 mg orally; mean 5.7 mg kg?1) and high-dose tapentadol (HighTAP, 50 mg orally; mean 11.4 mg kg?1) in a blinded crossover design with 7 day intervals. Statistical analysis was performed using anova with appropriate post hoc test (p ≤ 0.05).Results
Salivation was observed immediately following 11 out of 12 treatments with tapentadol. The ST was significantly increased at various time points in the opioid treatments. Hyperthermia (≥ 39.5 °C) was not observed. Baseline TT was 45.4 ± 1.4 °C for all treatments. Maximum TT values were 48.8 ± 4.8 °C at 1 hour in LowTAP, 48.5 ± 3.0 °C at 2 hours in HighTAP and 50.2 ± 5.3 °C at 1 hour in BUP. TT significantly increased after LowTAP at 1 hour, after HighTAP at 1–2 hours, and after BUP at 1–2 hours compared with baseline values. TTs were significantly increased in BUP at 1–2 hours compared with PBO.Conclusion and clinical relevance
Oral administration of tapentadol increased ST and TT in cats. The durations of thermal antinociception were similar between HighTAP and BUP, both of which were twice as long as that in LowTAP. Studies of different formulations may be necessary before tapentadol can be accepted into feline practice. 相似文献77.
Maria Federica Trombetta Francesco Nocelli Marina Pasquini 《Animal Science Journal》2017,88(8):1107-1112
In order to extend scientific knowledge on autochthonous Italian equine meat, the physical–chemical parameters of Catria Horse Longissimus thoracis (LT) muscle and its nutritional characteristics have been investigated. Ten steaks of Catria foal raised at pasture and fattened indoors for 2 months were dissected, and LT muscle was analyzed for chemical composition, total iron, drip loss, colorimetric characteristics, intramuscular fat, fatty acid profile and nutritional indexes. Steak dissection showed that LT muscle accounted for 36.78% and fat accounted for 9.19% of weight of steak. Regarding chemical composition, protein and fat content was 20.31% and 2.83%, respectively. Total iron content (1.95 mg/100 g) was lower than data reported in the literature. Color parameters showed a luminous and intense red hue muscle. The sum of unsaturated fatty acid composition (50.3%) was higher than the sum of saturated fatty acids (46.64 %). The fatty acid profile and nutritional values of Catria Horse meat could be modified adopting extensive rearing systems and grazing. The data suggests that further investigation on the composition of Catria Horse meat should be carried out to valorize this autochthonous breed, reared in sustainable livestock systems, and its meat in local short‐chain systems. 相似文献
78.
Olga Nikolaeva Marina Rozanova Mikhail Karpukhin 《Journal of Soils and Sediments》2017,17(4):1045-1053
Purpose
The objective of this research is to find out the spatial distribution of different traffic-related contaminants in urban topsoils across a highway (125,000 vehicles per day) in the city of Moscow, Russia.Materials and methods
The topsoils (0–3 cm depth) were sampled 1, 6, 10, 18, and 50 m perpendicular to the roadbed in three replicates 10 m apart. We analyzed total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAH), heavy metals in total and phyto-available forms (HM; Cu, Zn, and Pb), and deicing salts (DS; Cl?). The TPH were extracted with carbon tetrachloride and detected by spectrometry and PAH were extracted with methylene chloride, separated by high-performance liquid chromatography, and determined by fluorescence detector. Total HM were extracted by microwave acid digestion with aqua regia and phyto-available forms were extracted by NH4OAc and determined by inductively coupled plasma mass spectrometry. The DS were analyzed using an ion liquid chromatograph with a conductometric detector.Results and discussion
Heavy soil pollution was found within 1–6 m of the road. The TPH, B[a]P, and phyto-available HM concentrations exceeded permissible levels for Russia, while total HM and DS did not. The contaminant contents sharply decreased 10 m from the road. Within 10–50 m, they reached background levels, while PAH levels were elevated. We attribute this to the greater age of soils at 10–50 m than 1–6 m from the road. The different contaminant distribution patterns are attributed to their different transportation pathways: TPH, DS, and HM generally reach soils through road spray, splashes, melting snow moved from the road surface to roadsides, and aerosol sedimentation, whereas PAH are mainly transported as airborne particles and are thus able to reach more distant locations.Conclusions
Traffic-related soil pollution creates ecotoxicological and human-health risks. Distribution patterns vary by type of soil contaminant. The influence of the road on soil contamination was greatest within 10 m from the roadbed for TPH, HM, and DS and within 50 m for PAH. The increased PAH concentration levels with increased distance from the road highlights the importance of PAH monitoring in roadside soils.79.
Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.80.
Giulia Alberoni Davide Cavallini Marina Collina Agostino Brunelli 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(4):453-457
Up to 2005 the sensitivity of Stemphylium vesicarium (Wallr.) Simm., the causal agent of pear brown spot, to the strobilurin fungicides kresoxim-methyl, trifloxystrobin and pyraclostrobin
was still comparable with baseline values associated with good efficacy in the field. During 2006, the first resistant isolates
were detected in two commercial pear orchards in the Emilia-Romagna region (Italy), one of which was affected by considerable
control failure linked to strobilurin treatments as demonstrated in a field trial. In vitro sensitivity tests with 0.5 mg l−1 of kresoxim-methyl, trifloxystrobin and pyraclostrobin showed that in the population collected in the orchard with control
failure the conidial germination was greater than 90% compared to an untreated control both in 2006 and in 2007, i.e. 1 year
after the suspension of strobilurin applications. In the other orchard, where only a few symptomatic fruits were found and
the strobilurins were still in use, the conidial germination was lower, about 50% in 2006 and 25% in 2007. The molecular analysis
of mitochondrial cytochrome b gene of some monospore isolates with different levels of sensitivity confirmed the presence
of the mutation causing G143A substitution in all the resistant isolates. In conclusion, both in vitro tests and molecular
analysis confirmed the first occurrence of Stemphylium vesicarium resistance to all strobilurin fungicides tested. 相似文献