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51.
Mammal Research - The persistence of wildlife populations largely depends on females successfully rearing young through the earliest, most vulnerable period. During this period, mothers must...  相似文献   
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Genotyping of 2 well‐known weevil species from the genus Ceutorhynchus (Coleoptera: Curculionidae) distributed in west Palearctic, C. erysimi and C. contractus, revealed phenotype versus genotype inconsistencies in a set of 56 specimens (25 C. erysimi and 31 C. contractus) collected from 25 locations in Serbia and Montenegro. An analysis of the mitochondrial cytochrome oxidase subunit I gene (COI), widely used as a barcoding region, and a nuclear gene, elongation factor‐1α (EF‐1α), revealed stable genetic divergence among these species. The average uncorrected pairwise distances for the COI and EF‐1α genes were 3.8%, and 1.3%, respectively, indicating 2 genetically well‐segregated species. However, the genetic data were not congruent with the phenotypic characteristics of the studied specimens. In the first place, C. erysimi genotypes were attached to specimens with phenotypic characteristics of C. contractus. Species‐specific PCR‐RFLP assays for the barcoding gene COI were applied for the molecular identification of 101 additional specimens of both morphospecies (33 C. erysimi and 68 C. contractus) and were found to confirm this incongruity. The discrepancy between the genetic and morphological data raises the question of the accuracy of using a barcoding approach, as it may result in misleading conclusions about the taxonomic position of the studied organism. Additionally, the typological species concept shows considerable weakness when genetic data are not supported with phenotypic characteristics as in case of asymmetric introgression, which may cause certain problems, especially in applied studies such as biological control programs in which the biological properties of the studied organisms are the main focus.  相似文献   
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Main conclusion

In vitro conditions and benzyladenine influenced both content and composition of micropropagated Micromeria pulegium essential oils, with pulegone and menthone being the main essential oil components. The content and chemical composition of Micromeria pulegium (Rochel) Benth. essential oils were studied in native plant material at vegetative stage and in micropropagated plants, obtained from nodal segments cultured on solid MS medium supplemented with N6–benzyladenine (BA) or kinetin at different concentrations, alone or in combination with indole-3-acetic acid. Shoot proliferation was achieved in all treatments, but the highest biomass production was obtained after treatment with 10 μM BA. Phytochemical analysis identified up to 21 compounds in the essential oils of wild-growing and in vitro cultivated plants, both showing very high percentages of total monoterpenoids dominated by oxygenated monoterpenes of the menthane type. Pulegone and menthone were the main essential oil components detected in both wild-growing plants (60.07 and 26.85 %, respectively) and micropropagated plants grown on either plant growth regulator-free medium (44.57 and 29.14 %, respectively) or BA-supplemented medium (50.77 and 14.45 %, respectively). The percentage of total sesquiterpenoids increased in vitro, particularly owing to sesquiterpene hydrocarbons that were not found in wild-growing plants. Differences in both content and the composition of the essential oils obtained from different samples indicated that in vitro culture conditions and plant growth regulators significantly influence the essential oils properties. In addition, the morphology and structure of M. pulegium glandular trichomes in relation to the secretory process were characterized for the first time using SEM and light microscopy, and their secretion was histochemically analyzed.
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The synthesis of sulfenimines and sulfinimines has been carried out with 10‐hydroxyisocamphylthiol. The configuration of the compounds has been deduced by methods of NMR, DFT calculations and X‐ray diffraction analysis. The cytotoxic, antioxidant and membrane‐protective activity of the synthesized compounds as well as of the previously obtained sulfenimines and sulfinimines based on 4‐caranethiol have been determined.  相似文献   
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We investigated the effects of weak combined magnetic fields (MFs) produced by superimposing a constant MF (in the range 30 - 150 µT) and an alternating MF (100 or 200 nT) on cytokine production in healthy Balb/C male mice exposed 2 h daily for 14 days. The alternating magnetic field was a sum of several frequencies (ranging from 2.5 - 17.5 Hz). The frequencies of the alternating magnetic field were calculated formally based on the cyclotron resonance of ions of free amino acids (glutamic and aspartic acids, arginine, lysine, histidine, and tyrosine). The selection of different intensity and frequency combinations of constant and alternating magnetic fields was performed to find the optimal characteristics for cytokine production stimulation in immune cells. MF with a constant component of 60 μT and an alternating component of 100 nT, which was a sum of six frequencies (from 5 to 7 Hz), was found to stimulate the production of tumor necrosis factor-α, interferon-gamma, interleukin-2, and interleukin-3 in healthy mouse cells and induce cytokine accumulation in blood plasma. Then, we studied the effect of this MF on tumor-bearing mice with solid tumors induced by Ehrlich ascite carcinoma cells by observing tumor development processes, including tumor size, mouse survival rate, and average lifespan. Tumor-bearing mice exposed to a combined constant magnetic field of 60 μT and an alternating magnetic field of 100 nT containing six frequencies showed a strong suppression of tumor growth with an increase in survival rate and enhancement of average lifespan.  相似文献   
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Background: Invasive fungal infections are a major threat to a large cohort of immunocompromised patients, including patients with chemotherapy-associated neutropenia. Early differential diagnosis with bacterial infections is often complicated, which leads to a delay in empirical antifungal therapy and increases risk for adverse outcome. Accessibility and performance of specific fungal antigen and PCR-tests are still limited, while sepsis biomarkers are more broadly used in most settings currently.

Methods: Haematological patients hospitalized to receive chemotherapy with proven or probable invasive fungal infection or microbiologically proven bacterial bloodstream infection were included in the study. C-reactive protein was assessed daily during the profound neutropenia period, while procalcitonin or presepsin were measured during the first 48?hours after the onset of febrile episode.

Results: There were totally 64 patients included in the study, 53 with bacterial bloodstream infections and 11 with invasive fungal infections. Combination of CRP >120 with PCT <1.25 or presepsin <170 was shown to be a possible combined biomarker for invasive fungal infections in immunocompromised patients, with areas under the ROC-curves: 0.962 (95% CI 0.868 to 0.995) for PCT-based combination and 0.907 (95% CI 0.692 to 0.990) for presepsin-based combination.  相似文献   

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