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1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed.  相似文献   
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In experiments on sodium pentobarbital (40 mg/kg, i. p.) anesthetized mongrel cats of either sex weighting from 2.0 to 4.0 kg, it was stated, that sodium or lithium hydroxybutyrate (HOB) (200 mg/kg, i. v.) effectively slowed down breathing with inspiratory holdings. Thus 3-5 minutes after HOB administration, eupneic pattern of respiration was changed firstly to inspiratory apneustic one (100% of cats), and then to periodic one (80% of cats). This pattern persisted for 60-90 minutes, and after that the respiratory pattern usually changed its direction to the opposite one. In these conditions alterations of arterial blood composition (pH, pO2, pCO2, SO2) and hemodynamic variables (heart rate, arterial pressure) can not be considered as the cause of apneustic pattern of respiration. It is suggested, that HOB can be used for simulating such terminal respiratory patterns as apneustic and periodic ones.  相似文献   
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Hystological investigations of experimentally infected X. gerbilli minax have shown that at the early stages of the digestion, while in the intestine compact clots of non-digested blood, are preserved, proceeds the reproduction of the plague agent. With the decay of the alimentary clot it changes into the dying off of the microbe population and after the ceasing of digestion the accumulation of bacteria renews again. Simultaneously with the changes in the number of microbes their morphology varies. At the initial stage of blood digestion bacilli typical for the agent are dominant. With the decay of the alimentary clot they are replaced by ovoid and spheroid forms. After the ceasing of the digestion cycle the microbe mass is represented by small coccobacteria. During the decrease in the plague agent abundance bacteria are absent mostly often from the midgut and posterior parts of the alimentary canal. Most favourable conditions for their preservation exist in this period in the proventriculus and in adjoining to it oesophagus part.  相似文献   
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The [3H]guanosine and [3H]guanine label is shown to be distributed unevenly in the purine components of chicken tissues. 60 min after isotope administration about 80% of radioactivity is localized in xanthine and uric acid in the liver and duodenum, that agrees with high activity of purine nucleoside phosphorylase (EC 2.4.2.1) and guanine deaminase (EC 3.5.4.3). At the same time over 50% of label is found in the spleen in adenine nucleotides of the pool, RNA as well as in hypoxanthine and only 20% in oxypurines. Such a distribution of the label is in direct correlation with the activity of GMP-reductase (EC 1.6.6.8) catalyzing the reduction deamination of GMP in IMP.  相似文献   
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In view of the co-distribution of dopamine D2LR and 5-hydroxytryptamine 5-HT2A receptors (D2LR and 5-HT2AR, respectively) within inter alia regions of the dorsal and ventral striatum and their role as a target of antipsychotic drugs; in this study we assessed the potential existence of D2LR-5-HT2AR heteromers in living cells and the functional consequences of this interaction. Thus, by means of a proximity-based bioluminescence resonance energy transfer (BRET) approach we demonstrated that the D2LR and the 5-HT2AR form stable and specific heteromers when expressed in HEK293T mammalian cells. Furthermore, when the D2LR-5-HT2AR heteromeric signaling was analyzed we found that the 5-HT2AR-mediated phospholipase C (PLC) activation was synergistically enhanced by the concomitant activation of the D2LR as shown in a NFAT-luciferase reporter gene assay and a specific and significant rise of the intracellular calcium levels were observed when both receptors were simultaneously activated. Conversely, when the D2LR-mediated adenylyl cyclase (AC) inhibition was assayed we showed that costimulation of D2LR and 5-HT2AR within the heteromer led to inhibition of the D2LR functioning, thus suggesting the existence of a 5-HT2AR-mediated D2LR trans-inhibition phenomenon. Finally, a bioinformatics study reveals that the triplet amino acid homologies LLT (Leu-Leu-Thr) and AIS (Ala-Ile-Ser) in TM1 and TM3, respectively of the D2R-5-HT2AR may be involved in the receptor interface. Overall, the presence of the D2LR-5-HT2AR heteromer in discrete brain regions is postulated based on the existence of D2LR-5-HT2A receptor-receptor interactions in living cells and their codistribution inter alia in striatal regions. Possible novel therapeutic strategies for treatment of schizophrenia should be explored by targeting this heteromer.  相似文献   
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