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61.
Landscape Ecology - Ecological design used for stormwater management—referred to as Water Sensitive Urban Design (WSUD)—exemplifies how urban environments can benefit from mimicking...  相似文献   
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Background Goal and Scope  

The application of solid-liquid extraction is proposed to assess extractable fractions of components in soil. The application of a several step scheme could give a lot of information about mobility of metals associated with specific solid phases, especially after separation of top and bottom layers of studied soil. In this study, it was aimed to take into solution metal fractions of major (Ca, Mg, Mn, Fe) and trace elements (Cr, Co, Cu, Zn, As, Cd, Pb) from soil collected in urban areas. The fractions were defined by using chemical extraction operationally. The extraction behavior of studied elements in a six-step sequential extraction procedure is discussed with respect to the properties of the reagents used.  相似文献   
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Use of drug in lactating animal should be carefully considered due to its possibility of changes in pharmacokinetics as well as drug penetration in milk. The aim of this study was to assess the effect of lactation on pharmacokinetics of meloxicam after IV and IM administrations in goats. A crossover design (2 × 2) was used for each lactating and nonlactating group of goats with a 3-week washout period. Meloxicam (0.5 mg/kg) was administered into the jugular vein and upper gluteal muscle by IV and IM routes, respectively. The plasma and milk drug concentrations were determined by high-performance liquid chromatography with diode array detector, and the pharmacokinetic analysis was carried out by noncompartmental analysis. The pharmacokinetic parameters of meloxicam in lactating and nonlactating goats were not significantly different. The IM bioavailability of meloxicam was relatively lower in lactating (75.3 ± 18.6%) than nonlactating goats (103.8 ± 34.7%); however, the difference was not statistically significant. Moreover, AUC ratio between milk and plasma, which represent drug milk penetration, for both IV and IM administrations was less than 1 (about 0.3). In conclusion, pharmacokinetic parameters of meloxicam are not significantly altered by lactation for either the IV or IM routes of administration and this drug does not require a different dosage regimen for lactating animals.  相似文献   
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During the development and maturation of cereal grains, storage proteins are accumulated in the starchy endosperm. The enzymes responsible for the mobilisation of stored proteins during seed germination are cysteine endopeptidases and serine carboxypeptidases. In our previous study, we purified the major gliadin-degrading cysteine, endopeptidase EP8, from germinating triticale kernels. We confirmed in an experiment with exogenous gibberellic acid (GA3) that this enzyme is synthesised in aleurone during germination. In this study, the nucleotide sequence of EP8, a barley EP-A (HvEPA) homologue, and the expression pattern during grain development and germination have been analysed. Additionally, by comparing the activity of purified EP8 with the activity pattern of crude enzymatic extracts, the lack of enzyme activity in some tissues and during certain developmental stages has been demonstrated. The correlation of the results of the EP8 expression analysis with the activity pattern of this endopeptidase allowed us to formulate a hypothesis regarding the mechanism of EP8 activity regulation. We believe that the absence of active EP8 until the third day of germination may be associated with high levels of endogenous cystatin TrcC-4, which has the ability to inhibit EP8 in vitro.  相似文献   
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The aim of this study was to investigate the evolution of the abundance of cytochrome oxidase c subunit IV (NCOIV) and beta subunit of ATP synthase (β-ATP) during the last third of gestation in bovine skeletal muscles. Semitendinosus, longissimus thoracis and rectus abdominis muscles were chosen for the immunoblotting of the respective protein levels. Muscle and blood samples from bovine fetuses of randomly selected breeds were collected at 180, 210, and 260 days post-conception (dpc). The muscle tissue expressions of NCOIV, β-ATP were compared to blood glucose and insulin. At 260 dpc, protein levels of NCOIV raised in skeletal muscles. Additionally, β-ATP in semitendinosus and longissimus thoracis were elevated and paralleled by higher concentrations of blood serum insulin. It corroborates our previous observations indicating that accelerated metabolic differentiation of bovine skeletal muscles is associated with elevated blood insulin and occurs during the last trimester of gestation. Our observations point to the connection between insulin-sensitivity and the molecular mechanisms of mitochondrial contribution to ontogenesis of skeletal muscles.  相似文献   
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Changes in semen quality and selected biochemical markers were analyzed during a week of spawning season of common carp Cyprinus carpio L. Semen was obtained twice, on May 30 and on June 7, and each time it was collected 24 h after hormonal stimulation using Ovopel [(d-Ala6, Pro9 NEt)-mGnRH + metoclopramide] in 1 pellet kg?1. The total volume of semen (ml), volume of semen per kg of body weight (ml kg?1 b.w.), sperm concentration (×109 ml?1), total number of sperm per kg of body weight (×109 kg?1 b.w.), pH of semen, pH of seminal plasma, seminal plasma osmotic pressure (mOsm kg?1) and the total protein content in seminal plasma (mg ml?1) were determined. A 10 mM Tris buffer containing 100 mM NaCl with 0.5 % BSA (pH 9.0, osmolality 200 mOsm kg?1) was used to activate sperm. The following computer-assisted sperm analysis (CASA) parameters were determined: percentage of motile sperm (MOT, %), progressively motile sperm (PRG, %), curvilinear velocity (VCL, μm s?1), straight-line velocity (VSL, μm s?1), movement linearity (LIN, %), wobbling index (WOB, %), amplitude of lateral head displacement (ALH, μm) and beat cross-frequency (BCF, Hz). The volume of semen per kg of BW, total number of sperm per kg of BW and semen pH were significantly lower at the second semen sampling compared to the first semen sampling. Volume of semen at the second sampling correlated positively with CASA parameters. A lack of differences among CASA parameters between both collection periods indicates good quality of carp sperm hormonally stimulated with Ovopel twice at a 1-week interval.  相似文献   
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A method for actively protecting river lamprey and increasing the number of river lamprey populations is presented as protocol of rearing stocking material. The objective of the study was to accommodate lamprey larvae during the most critical life period under controlled conditions until they reach a sufficient size, which will increase their chances to survive in the natural environment. The eggs obtained from wild breeders were incubated in Weiss’s jars at the water temperature of 12 °C. The larvae were reared in tanks set up in closed recirculating aquaculture systems. During the rearing period, the water temperature was 20 °C and the density of larvae was 150 individuals per 1 dm2 of bottom. In the initial rearing phase, the main focus was on the type of feeds and the nourishment method. It was determined that the most suitable feed type was Artemia nauplii combined with Hikari dry food. Additionally, the type of substrate was tested under controlled conditions. In this case, the optimum one was composed of sand of the grain size between 0.3 and 0.5 mm. The experiment proved that it is possible to successfully conduct river lamprey larvae rearing under controlled conditions. The growth rates are comparable to or better than those achieved under natural conditions. After 30 days of the rearing period, the lamprey larvae were 25 mm long. The results create a possibility to develop a technology for the restitution of river lamprey and other lamprey species, which are endangered throughout the world.  相似文献   
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