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991.
The present study examines the direct effect of luteinising hormone (LH) on the reactivity of the porcine uterine artery to norepinephrine (NE). Three-mm-long arterial segments collected during the luteal phase of the oestrous cycle were mounted in an organ bath for isometric tension recording. After 30 min of equilibration in optimal passive tone, one part of the vessels was treated with 10 ng/ml of LH in PBS (experimental), while a second part of the arterial segments was treated with 10 ng/ml of bovine serum albumin (BSA) in PBS (control). After 30 min of equilibration, NE was given to each organ bath in a cumulative concentration manner, ranging between 1 x 10(-8) mol/l to 3 x 10(-4) mol/l. NE caused a dose-dependent contraction of all experimental and control arteries. The addition of LH caused a rightward shift of the dose-response curve to NE. The corresponding EC50 values were 2.17 (+/- 0.39) micromol/l in PBS-pretreated vessels and 3.35 (+/- 0.41) micromol/l in LH-pretreated vessels (P < 0.05). The results of the present study demonstrate that LH attenuates the vascular response to NE in third-order branches of the uterine artery. Therefore, it can be suggested that besides the known effect of LH-hCG on the formation of vasoactive eicosanoids, an additional mechanism is involved in the direct action of LH on blood flow in the uterine arteries in pigs. 相似文献
992.
Ruszczyńska A Szteyn J Wiszniewska-Laszczych A 《Polish journal of veterinary sciences》2007,10(2):119-121
Producing dairy products which are safe for consumers requires the constant monitoring of the microbiological quality of raw material, the production process itself and the end product. Traditional methods, still a "gold standard", require a specialized laboratory working on recognized and validated methods. Obtaining results is time- and labor-consuming and do not allow rapid evaluation. Hence, there is a need for a rapid, precise method enabling the real-time monitoring of microbiological quality, and flow cytometry serves this function well. It is based on labeling cells suspended in a solution with fluorescent dyes and pumping them into a measurement zone where they are exposed to a precisely focused laser beam. This paper is aimed at presenting the possibilities of applying flow cytometry in the dairy industry. 相似文献
993.
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
994.
Daniel Moreno-Fernández Mariola Sánchez-González Juan G. Álvarez-González Andrea Hevia Juan P. Majada Isabel Cañellas Guillermo Gea-Izquierdo 《European Journal of Forest Research》2014,133(5):833-843
Pruning allows knot-free timber to be obtained, thereby increasing the value of the highest-value wood products. However, the effect of pruning on growth is under discussion, and knowledge about the tree response to the simultaneous development of thinning and pruning is scarce. The objective of this study was to analyze the effect of the interaction of thinning and pruning on tree and stand level and the annual radial growth of two pine species native to Mediterranean mountains. We used long-term data of three trials installed in pine stands where several combinations of pruning and thinning were developed. Five inventories were carried out for each trial, and the mean dasometric features of the different treatments were compared using linear mixed models including a competition index. In addition, we collected cores from ten trees per plot in order to evaluate the annual response of trees to the thinning and pruning. We analyzed the annual radial growth using a semiparametric approach through a smooth penalized spline including rainfall and temperature covariates. Pruning did not show any effect on growth. However, larger diameter and increased annual radial growth were found in thinned plots, both with and without pruning, as compared to unthinned plots. Also, we found significant effects of climate on annual radial growth. We recommend the application of thinning and pruning in stands of Mediterranean mountains in order to get knot-free timber since growth reduction was not found in thinned stands. 相似文献
995.
Jacek Wolnicki Leszek Myszkowski MichaŁ Korwin-kossakowski Rafał Kamiński L. Andrzej Stanny 《Aquaculture International》2006,14(1-2):89-98
In a laboratory experiment at 28 °C, four commercial starters (Carp Starter, Uni Starter, Perla Plus, Asta) were fed intensively
to 11-month-old juvenile tench Tinca tinca of initially 41 mm TL and 0.70 g BW, over a period of 120 days. Frozen chironomid larvae were fed to fish below satiation
as a reference diet for comparison of the fish body chemical composition. Final survival rates of 99–100% and satisfactory
growth were attained with all dry diets, ranging from 73.3 (Carp Starter) to 84.8 mm TL (Asta) and from 5.39 (Carp Starter)
to 8.09 g BW (Perla Plus). External body deformities of up to 96.4% specimens appeared in those fed Uni Starter, Carp Starter
and Perla Plus, whereas 0% were recorded for Asta and chironomids. Fish in groups with deformities showed significantly elevated
lipid content in their bodies, lower ash content and higher condition coefficient values. Juveniles in groups without deformities
did not substantially change lipid content, but the ash content increased. Thus, among four dry diets studied, only Asta starter
can be fed effectively and safely to juvenile tench reared intensively under controlled conditions. 相似文献
996.
Andrzej Kamocki Maria Urbańska Urszula Biereżnoj-Bazille Małgorzata Ożgo 《水产资源保护:海洋与淡水生态系统》2021,31(7):1918-1924
- Local extinctions break species interactions and have cascading effects throughout ecosystems; parasites are often severely affected. The European bitterling, Rhodeus amarus, is a cyprinid fish that parasitizes unionid mussels by laying eggs into the mussel gill cavity, where embryos develop and emerge as active juveniles; this relationship is obligatory for the bitterling.
- This article describes a field experiment aimed at averting the secondary extinction of the European bitterling after a complete die-off of a freshwater mussel community, as a result of habitat destruction.
- Approximately 5,000 unionid mussels were reintroduced within the short time frame in which the remnant bitterling population was still present at the site. Mussel survival was high, and bitterling resumed reproduction, with vigorous courtship observed within 24 hours of mussel release. Recruitment was successful, as evidenced by increased occupancy, densities, and relative frequencies in the fish assemblage. The frequency of sub-adults and young-of-the-year changed from 0% before mussel reintroduction to 80% a year later, and 50% 2 years later, when young-of-the-year contributed to about half of the young fish. No bitterling were observed at two control sites where mussels were not reintroduced.
- This study exemplifies how the timely restitution of affiliate species can avert co-extinction. It also shows how the conservation of the bitterling within its historical distribution range can serve mussel conservation, including species that although not legally protected, are important keystone species and ecosystem engineers, shaping the structure and function of a broad range of freshwater habitats.
997.
European Journal of Forest Research - 相似文献
998.
M. Wrzosek M. Płonek O. Zeira J. Bieżyński W. Kinda M. Guziński 《The Journal of small animal practice》2014,55(7):375-378
A three‐year‐old Border collie was diagnosed with a bipartite atlas and bilateral forelimb hypodactyly. The dog showed signs of acute, non‐progressive neck pain, general stiffness and right thoracic limb non‐weight‐bearing lameness. Computed tomography imaging revealed a bipartite atlas with abaxial vertical bone proliferation, which was the cause of the clinical signs. In addition, bilateral hypodactyly of the second and fifth digits was incidentally found. This report suggests that hypodactyly may be associated with atlas malformations . 相似文献
999.
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1000.