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1.
In natural environments, predation risk varies over time. The risk allocation hypothesis predicts that prey is expected to adjust key anti‐predator behaviours such as vigilance to temporal variation in risk. We tested the predictions of the risk allocation hypothesis in a natural environment where both a species‐rich natural predator community and human hunters are abundant and where the differences in seasonal and circadian activity between natural and anthropogenic predators provided a unique opportunity to quantify the contributions of different predator classes to anti‐predator behaviour. Whereas natural predators were expected to show similar levels of activity throughout the seasons, hunter activity was high during the daytime during a clearly defined hunting season. According to the risk allocation hypothesis, vigilance should then be higher during the hunting season and during daytime hours than during the non‐hunting season and night‐time hours. Roe deer (Capreolus capreolus) on the edge of Bia?owie?a Primeval Forest in Eastern Poland displayed vigilance behaviour consistent with these predictions. The behavioural response of roe deer to temporarily varying predation risks emphasises the behavioural plasticity of this species and suggests that future studies of anti‐predator behaviour need to incorporate circadian variation in predation pressure as well as risk gradients of both natural and anthropogenic predators.  相似文献   
2.
In this paper we describe synthesis, structures and some physicochemical properties of 20 isothiazolopyridines 813 substituted differently into an isothiazole ring as well as their in vitro antibacterial assays against Mycobacterium tuberculosis H37Rv, Mycobacterium fortuitum PCM 672 and Propionibacterium acnes PCM 2400. Compound 13a was found to be the most active derivative against M. tuberculosis H37Rv, demonstrating 100% growth inhibition of microorganisms in the primary screen (minimum inhibitory concentration [MIC] 6.25 μg/mL). Nineteen of the prepared compounds were evaluated against M. fortuitum PCM 672 and P. acnes PCM 2400 and only compounds 9 and 12d exhibited excellent activity against individual strains of microorganisms with MIC90 <1 μg/mL. The inhibitory action of the remaining isothiazolopyridines towards the tested strains of the microorganism was low, absent, or a non-linear correlation prohibited accurate determination of MIC values. Unexpectedly, seven of the remaining isothiazolopyridines tested against M. fortuitum and P. acnes stimulated growth of the microorganisms in the range 10–50% or even more (10b) under experimental conditions.  相似文献   
3.
Evaluation of chemicals cytotoxicity plays fundamental role in many in vitro investigations. The way of assessment of cytotoxicity depend on aim of study, characteristic of used cells and mode of action of investigated chemicals. The principal aspect of these investigations is validation of used method. In this paper validation of three different cytotoxicity assays is presented: total cell number measurement (LK), microplate assay measured mitochondrial dehydrogenase activity (MTT) and colorimetric assay measured ability of live cell to uptake neutral red (NR). The investigation was performed on different cells (MRC5, CV1 i Chang Liver) with DMSO as reference agent.  相似文献   
4.
Several mammal species have recolonized their historical ranges across Europe during the last decades. In November 2012, a wolf-looking canid was found dead in Thy National Park (56° 56′ N, 8° 25′ E) in Jutland, Denmark. DNA from this individual and nine German wolves were genotyped using a genome-wide panel of 22,163 canine single nucleotide polymorphism (SNP) markers and compared to existing profiles based on the same marker panel obtained from northeastern Polish (n?=?13) wolves, domestic dogs (n?=?13) and known wolf-dog hybrids (n?=?4). The Thy canid was confirmed to be a wolf from the German-western Polish population, approximately 800 km to the southeast. Access to the German reference database on DNA profiles based on 13 autosomal microsatellites of German wolves made it possible to pinpoint the exact pack origin of the Thy wolf in Saxony, Germany. This was the first documented observation of a wolf in Denmark in 200 years and another example of long-distance dispersal of a carnivore.  相似文献   
5.
Respiratory Syncytial Virus (RSV) is one of the most common causes of lower respiratory tract infections in young children, immunocompromised patients (children and adults), patients with chronic respiratory diseases and elderly people. Reinfections occur throughout the life, but the severity of disease decreased with subsequent infection. The aim of this study was to analyze the frequency of RSV infections in two selected subpopulations: young children (below 5 y.) and adults with chronic respiratory diseases (25-87 y.). Nasopharyngeal swabs (334) collected from October 2008 to March 2010 were examined. The presence of RSV genome was determined by RT-PCR and the presence of RSV antigen by quick immunochromatographic test. Positive results of RT-PCR were found in 45.2% of all swabs: 48.6% samples in 2008; 41.5% in 2009; 50.8% in 2010. The highest frequency of RSV-positive samples was in fall-winter months, but differences in RSV epidemic seasons were found. In the first season (2008-2009) an increased number of RSV infections was observed from November 2008, but in the second season--from January 2010. Generally, the frequency of RSV-positive RT-PCR among children was 53%, among adults 25%. The highest difference was observed in the first three-month period of 2010. RT-PCR positive samples were found in 68.5% of children and 5.9% of adults. However, the RSV antigen was found in 44.4% of samples collected from adults in this period. Our results indicate that the contribution of RSV infections during epidemic season of respiratory tract infections in Poland was really high among children and adults.  相似文献   
6.
This study was designed to evaluate the degree of exposure of pet dogs from an urban area of NW Poland to selected metals, including toxic Cd and Pb. The study was conducted on a group of 48 healthy dogs. The serum concentration of the analysed elements followed the order Fe > Al > Zn > Cu > Mn > As > Sr > Pb > Cd > Cr > Ni > V. The presence of cadmium and lead was found in all the serum samples tested. The average contents of these elements were 0.309 and 0.489???g/mL. The factors that played the greatest role in the intake of the analysed elements were diet and breed-dependent size of dogs. Small-sized dogs had higher concentrations of all elements compared with large dogs, with statistically significant differences noted for Cu, Pb, Cd and Sr. It was also found that dogs receiving commercial and mixed food had more metals in serum compared with dogs on homemade food (except strontium). The present study showed elevated concentrations of some heavy metals (Pb, Cd, Fe and Cu) in serum of pet dogs, which is probably due to the excess elemental load of this area. Given that no information is available on the concentrations of strontium, vanadium and aluminium in dogs, further research is necessary to determine certain reference values which would allow for an easier interpretation of results and evaluation of exposure to these elements.  相似文献   
7.
Piroplasms from Theileria genus were detected in blood and spleen of red deer Cervus elaphus culled during the months of September 2004–January 2005 in northwestern Poland. The polymerase chain reaction revealed the presence of Theileria deoxyribonucleic acid in 88% (36 of 41) of the animals examined. Molecular characterization of the parasites based on large piece of 18S ribosomal ribonucleic acid gene containing hypervariable region V4 showed 99.9% similarity to two Theileria spp. sequences: Theileria sp. 3185/02 and Theileria capreoli BAB1158. Phylogenetic analysis confirmed that the three isolates cluster together with high bootstrap support. It is supposed that those pathogens can be classified as one group characteristic for the Eurasian continent, contrary to protozoon of Theileria from the T. cervi group, which are often found on the North American continent and can also infect the representatives of Cervidae. In conclusion, this study suggested that free-living C. elaphus in northwestern Poland are a competent reservoir of Theileria sp. ZS T04 C.e. parasites, although the vector of the piroplasms is still unknown.  相似文献   
8.
The study aimed at comparing the changes in the content of free amino acids, phenolic compounds and the activity of PAL and TAL caused by two piercing-sucking arthropods: the grape mealybug (Pseudococcus maritimus Ehrh.) and the two-spotted spider mite (Tetranychus urticae Koch) in the leaves of orchid and strawberry, respectively. The obtained results show that the amino acid content and the ratio of amino acids to phenolic compounds increased in both plant species infested by the mealybug and the mite. However, such response was weakly dependent on changes in activity of the analysed enzymes. The pest feeding affected accumulation of the phenolic compounds, since the induction of the PAL activity in mealybug-infested orchid leaves during the first 5 h of the experiment preceded the increase in phenolic compounds during the first week of insect feeding. Instead, the increased activity of TAL was accompanied by elevated levels of phenolic compounds in the leaves of strawberry infested by mites. Mechanisms of biochemical plant responses induced by infestation of the studied herbivorous arthropods are discussed.  相似文献   
9.
In the present study, PCR has been applied to detect and analyze DNA of Babesia spp. extracted from Ixodes ricinus ticks. Collection of I. ricinus was made in 6 forested areas of Zachodniopomorskie Voivodship, Poland, during 2 seasonal peaks of tick activity, i.e., spring and autumn, 2001. In total, 1,328 I. ricinus were collected and processed for PCR with F34 and R323 primers. Babesia spp. was detected in 28 (2% of 1,328 tested) ticks; 26 were identified as B. divergens. The other 2 were identified as B. microti. PCR was conducted with 18S rRNA specific primers and sequencing was processed to precisely identify and compare these isolates with B. microti and B. divergens sequences from Europe, North America, and Asia obtained from the GenBank. Analysis revealed that sequences of B. microti from northwestern Poland are almost identical (99.94%) with those referred to as "Munich strain"; both form a clade different from other European strains, as well as those from Asia and North America (called B. microti, sensu stricto). An investigation performed with B. divergens sequences showed that the sequence from northwestern Poland is 99.94% homologous to an isolate from Ireland ("Purnel"), and differs in just a few nucleotides from other European sequences. Phylogenetic analysis revealed that the sequence of B divergens isolated from Polish ticks form a group that comprise 4 European sequences from Great Britain and Ireland and is, therefore, closely related to other European and North American B. divergnens sequences.  相似文献   
10.
The present study was undertaken to evaluate the concentration of selenium and selected heavy metals and their possible relationship in serum of 25 healthy lactating cows (Montbéliarde) reared in a non-polluted area, in the western part of Poland. Cadmium, lead, copper, and zinc concentrations were determined by inductively coupled plasma-atomic emission spectrometry and Se concentration was determined fluorimetrically. The content of Se, Zn, and Cu was 0.083?±?0.026, 0.629?±?0.413, and 0.152?±?0.042?μg/mL, respectively. The presence of the Cd and Pb was found in all serum samples. The mean concentration of these metals was 0.0009?±?0.0008 and 0.018?±?0.016?μg/mL, respectively. Analysis of correlations between Se and toxic metals showed a negative and significant (P?相似文献   
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