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排序方式: 共有280条查询结果,搜索用时 31 毫秒
271.
Joanna Tunikowska Przemysław Prządka Zdzisław Kiełbowicz 《Reproduction in domestic animals》2020,55(Z2):32-37
Light-based technologies are applied in various fields of medicine: for example optical diagnostics, light-activated therapy and surgery. Although light-based surgical procedures had hardly been a novelty, the revolutionizing moment for surgery came with the first use of light to cut tissue. Nowadays, surgical lasers are routinely used across numerous medical specialties, including gynaecology and urology. They are a part of the surgical treatment of benign prostatic hyperplasia, prostate carcinoma, penis carcinoma, genital skin lesions and orchidectomy. While in human urology lasers continue to establish their position as one of the standard surgical tools, veterinary patients are rarely treated with what here is still considered a technical innovation. However, through research on laser treatment of the prostate hyperplasia conducted on a canine model, veterinary medicine has gained a massive portion of data. It may prove beneficial for our clinical patients. In this review, we introduce the very principles of laser surgery as well as its current and future applications in oncologic surgery of the canine prostate gland and the male reproductive system. 相似文献
272.
273.
Joanna Paczuska Zdzis?aw Kie?bowicz Marcin Nowak Agnieszka Antończyk Rafa? Ciaputa Jakub Nicpoń 《Acta veterinaria Scandinavica》2014,56(1):1
Background
Tumors of the skin and subcutaneous tissue are the largest group of canine neoplasms. Total excision is still the most effective method for treatment of these skin tumors. For its universal properties the carbon dioxide (CO2) laser appears to be an excellent surgical instrument in veterinary surgery. Laser techniques are alternatives to traditional methods for the surgical management of tumors. The aim of this study was to compare various types of laser techniques in skin oncologic surgery: excision, ablation and mixed technique and to suggest which technique of CO2 laser procedure is the most useful in particular case of tumors in dogs.Findings
The study was performed on 38 privately-owned dogs with total number of 40 skin tumors of different type removed by various CO2 laser operation techniques from 2010–2013. The treatment effect was based on the surgical wound evaluation, the relative time of healing and possible local recurrence of the tumor after 3 months post surgery. Local recurrence was observed in two cases. The study showed that in 30 cases time needed for complete resection of lesions was less than 10 minutes. Time of healing was longer than 12 days in 6 cases (42.8%) with tumor excision and in 14 cases (87.5%) where excision with ablation technique was performed.Conclusions
The advantages of the CO2 laser surgery were better hemostasis, precision of working, non-contact dissection, less instruments at the site of operation and minimum traumatization of the surrounding tissues. 相似文献274.
The aim of this study was to determine the level of circulating immune complexes (CIC) in equine serum and the electrophoretic properties of the protein fraction thereof. The study was carried out using 42 clinically healthy breeding horses of noble half-blood. The average extinction value of CIC's in equine serum was E450 nm = 0.278 ± 0.09 nm. Generally, 23 protein fractions were identified in the molecular mass range between 294 and 25 kDa. Eight fractions whose molecular masses were 137, 72, 65, 52, 42, 32, 28, and 26 kDa, respectively, appeared in all analyzed samples. In 20 of the analyzed serum an additional nine protein fractions whose molecular masses were 260, 110, 84, 78, 67, 62, 57, 45, and 39 kDa, respectively, were identified. Circulating immune complexes are a source of information about immunologic processes that take place in mammals. Determining the average values of CIC levels and identifying the electrophoretic profile of proteins in clinically healthy horses could be useful in research and diagnostics. 相似文献
275.
Adam Kaliński Mirosława Bańbura Michał Glądalski Marcin Markowski Joanna Skwarska Jarosław Wawrzyniak Piotr Zieliński Iwona Cyżewska Jerzy Bańbura 《Landscape Ecology》2014,29(9):1521-1530
Integration of landscape ecology and conservation physiology has been recommended as a potentially useful way to investigate consequences of human-induced changes in habitats for animal populations. A central goal of this paper was to examine if a simple physiological parameter displays any consistent patterns of spatio-temporal variation. Blood glucose concentration in birds reflects their high metabolic demands and may be influenced by a number of environmental factors. Therefore we present results concerning variation in glucose concentration in the blood of c. 14-day-old nestling blue tits (Cyanistes caeruleus) in central Poland in an 8-year period, 2005–2012, in two landscapes: an urban parkland and a deciduous forest. The most important findings of the study were: (1) mean levels of blood glucose varied markedly among years, most probably due to variable weather conditions, (2) glucose concentrations were significantly higher in the parkland study site than in the forest site, (3) heavier nestlings had lower glucose levels, and (4) high glucose levels were negatively correlated with fledging and breeding success. Thus we have confirmed that a consistent spatio-temporal pattern really exists. 相似文献
276.
Pavlo Bekhta Stanisław Proszyk Tomasz Krystofiak Miroslava Mamonova Grzegorz Pinkowski Barbara Lis 《Wood material science & engineering》2014,9(4):233-245
The effect of short-term thermomechanical densification of veneer on the surface roughness and surface anatomical changes in four wood species – alder (Alnus glutinosa Gaertn.), beech (Fagus sylvatica L.), birch (Betula verrucosa Ehrh.), and pine (Pinus sylvestris L.) – was studied. Veneer sheets were densified at a temperature of 100, 150, or 200°C and at a pressure of 4, 8, or 12 MPa for 4 minutes. Seven roughness parameters such as Ra, Rz, Rq, Rp, Rv, Rsk, and Rku were determined. Profile surface was recorded using a modified Carl Zeiss ME-10 profile gauging profilometer. Surface anatomical changes of veneer were examined using scanning electron microscopy. The results showed that densification temperature and pressure affect surface roughness of veneer. The surface became smoother, and roughness values decreased significantly (except for Rku which increased slightly) with increasing temperature and pressure of densification. The effect of temperature on surface roughness changes is more pronounced compared with that of densification pressure. The lowest values of surface roughness were recorded for pine veneer samples followed by alder, birch, and beech samples. These results can be used to provide initial data for adhesive application processes in woodworking industry. 相似文献
277.
When infested with Fusarium sp., the cereals Triticum aestivum L. emend. Fiori et Paol. cv. ‘Bombona’, Avena sativa L. cv. ‘Deresz’, and Hordeum vulgare L. cv. ‘Rastik’ can emit volatile organic compounds (VOCs). The VOCs differ both qualitatively and quantitatively from those emitted by non-infested wheat, oat, and barley plants. We detected increased amounts of VOCs released by green leaves (green leaf volatiles – GLVs): (Z)-3-hexenal, (E)-2-hexenal, (Z)-3-hexen-1-ol, (E)-2-hexen-1-ol, (Z)-3-hexen-1-yl acetate, 1-hexyl acetate as well as the other VOCs like (Z)-ocimen, linalol, linaloloxide, benzyl acetate, indole, and β-caryophyllene. The lipoxygenase pathway resulted in the highest release of GLVs in comparison to the other biochemical pathways of volatile production. As a result of Fusarium infestation, the amounts of VOCs varied between tested cereals. We also subjected uninfested wheat, barley, and oat plants to infested wheat plants, and found that these cereals released larger amounts of VOCs compared to control plants. Emitted amounts of VOCs were significantly higher the shorter the distance between uninfested and infested plants. 相似文献
278.
Kormanek Mariusz Małek Stanisław Banach Jacek Durło Grzegorz Jagiełło-Leńczuk Krystyna Dudek Katarzyna 《New Forests》2021,52(2):271-283
New Forests - Cultivation of seedlings in trays requires the use of specifically developed substrates. This study presents the results of the analyses of selected physical and mechanical parameters... 相似文献
279.
Niemczyk Marzena Chmura Daniel J. Socha Jarosław Wojda Tomasz Mroczek Piotr Gil Wojciech Thomas Barb R. 《European Journal of Forest Research》2021,140(6):1341-1361
European Journal of Forest Research - The contribution of Douglas-fir (Df) to European forests is likely to increase as the species is a potential adaptation option to climate change. In this... 相似文献
280.
Effect of soil drought on growth and yield of maize (Zea mays L.) hybrids grown under compacted soil
Maciej T. Grzesiak Tomasz Hura Anna Maksymowicz Kinga Dziurka Grzegorz Rut Andrzej Rzepka Stanisław Grzesiak 《Journal of Agronomy and Crop Science》2023,209(2):300-315
In this study, we examined responses of maize hybrids differing in susceptibility to soil compaction and drought in the case of their separate or combined action. We ran field and greenhouse experiments and determined effects on grain yield, biomass, weight of 1000 grains, shoot and roots dry matter (DM), shoot-to-roots ratio, harvest index, plant height, emergence index, leaf area and greening and root number and length. Individual and combined effects of both stresses were observed in the field and greenhouse. Compared with plants growing in loose soil and optimal irrigation (LI), the resistant hybrids in treatments HI, LD and HD showed a smaller reduction in GY, BY, S, R, RN and RL than the sensitive. In both groups, stress influence on HA, W-1000, LA and SPAD was smaller and the differences were insignificant. Compared with LI treatment, the roots of LD, HI and HD increased their DM, number and length in the upper level of the soil profile and the number of roots developed at 0–30° and 30–60° in relation to the root main axis. Analysis of those traits in the hybrids resistant and sensitive to both stress factors enabled to explain a defence response. Our study demonstrated that soil compaction and soil drought, which usually occurs simultaneously, caused significant changes in components of plant yield and showed plant plasticity in response to environmental factors under natural conditions. 相似文献