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61.
In this study we investigate population genetic structure and phylogeography of the bent-wing bat complex ( Miniopterus schreibersii ) in Asia Minor and adjacent regions. PCR amplification and sequencing of the first hypervariable domain of the mitochondrial control region were used to obtain the genetic data. Morphometric differentiation between lineages was analysed by comparing forearm lengths. We found two reciprocally monophyletic lineages within the M . schreibersii complex, identified as M.   s. schreibersii and M. s . pallidus . Distributions of the lineages were allopatric with a U-shaped suture zone passing through Central Anatolia. The suture zone separated coastal regions occupied by M.   s. schreibersii from inland, higher altitude regions occupied by M.   s. pallidus . The lineages showed a considerable sequence divergence of c . 9%, accompanied by a corresponding difference in forearm length. The presence of the genetically distinct lineages, with allopatric distribution and corresponding morphometric differences, probably reflects their long isolation during the ice-age in the Balkans and the Caspian/Caucasus refugia, followed subsequently by expansion into different habitats. Based on the present data, the lineages can be recognized as evolutionary significant units.  相似文献   
62.
This study was conducted in Turkish osteoarthritis patients to determine the frequency of I/D polymorphism genotypes of angiotensin converting enzyme gene, and to examine the role of this polymorphism in osteoarthritis development. Genomic DNA obtained from 200 persons (135 patients with osteoarthritis and 65 healthy controls) was used in the study. DNA was multiplied by polymerase chain reaction using I and D allele-specific primers. Polymerase chain reaction products were assessed with CCD camera by being exposed to 2% agarose gel electrophoresis. There was statistically significant difference between the groups with respect to genotype distribution (P < 0.001). The D allele frequency was indicated as 69% and I allele was as 31% in the patients, whereas it was 55–45% in the control group. Consequently, in this study, we may assert that ACE gene I/D polymorphism DD genotype determination is significant criteria for identifying patients who are likely to develop osteoarthritis in east population of Turkey.  相似文献   
63.
Serotonin (5-hydroxytryptamine, 5-HT) is an important neuromodulator in learning and memory processes. A functional genetic polymorphism of the 5-HT 2a receptor (5-HTR2a His452Tyr), which leads to blunted intracellular signaling, has previously been associated with explicit memory performance in several independent cohorts, but the underlying neural mechanisms are thus far unclear. The human hippocampus plays a critical role in memory, particularly in the detection and encoding of novel information. Here we investigated the relationship of 5-HTR2a His452Tyr and hippocampal novelty processing in 41 young, healthy subjects using functional magnetic resonance imaging (fMRI). Participants performed a novelty/familiarity task with complex scene stimuli, which was followed by a delayed recognition memory test 24 hours later. Compared to His homozygotes, Tyr carriers exhibited a diminished hippocampal response to novel stimuli and a higher tendency to judge novel stimuli as familiar during delayed recognition. Across the cohort, the false alarm rate during delayed recognition correlated negatively with the hippocampal novelty response. Our results suggest that previously reported effects of 5-HTR2a on explicit memory performance may, at least in part, be mediated by alterations of hippocampal novelty processing.  相似文献   
64.
Novel dioxoacridine sulfonamide compounds were synthesized from reaction of cyclic 1,3-diketones, sulfanilamide (4-amino benzene sulfonamide) and aromatic aldehydes. The structures of these compounds were confirmed by using spectral analysis (IR, H-NMR, (13)C-NMR, and mass). Human carbonic anhydrase isoenzymes (hCA I and hCA II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of sulfanilamide, acetazolamide (AAZ), and newly synthesized sulfonamides on hydratase and esterase activities of these isoenzymes have been studied in vitro. The IC(50) values of compounds for esterase activity are 0.71-0.11 μM for hCA I and 0.45-0.12 μM for hCA II, respectively. The K(i) values of these inhibitors were determined as 0,38-0,008 μM for hCA I and 0,19-0,001 μM for hCA II, respectively.  相似文献   
65.
Sample-probe contact duration (dwell time) and loading force are two important parameters for the atomic force microscopy (AFM) force spectroscopy measurements of ligand-receptor interaction. A prolonged contact time may be required to initiate ligand-receptor binding as a result of slow on-rate kinetics or low reactant density. In general, increasing contact duration promotes nonspecific interactions between the substrate and the functionalized cantilever and, thus, masking the detection of the specific interactions. To reduce the nonspecific interactions in AFM force measurements requiring extended substrate-probe contact, we investigated the interaction of bovine serum albumin (BSA)-functionalized cantilever with BSA-coated glass, polyethylene glycol (PEG)-functionalized glass, Pluronic-treated Petri dishes and agarose beads. The frequency of nonspecific interaction between the BSA-functionalized cantilever and the different samples increased with loading force and dwell time. This increase in nonspecific adhesion can be attributed to the interaction mediated by forced unfolding of BSA. By reducing the loading force, the contact duration of the AFM probe with an agarose bead can be extended to a few minutes without nonspecific adhesion.  相似文献   
66.
In this work, we present a time-scale analysis based model reduction and parameter identifiability analysis method for metabolic reaction networks. The method uses the information obtained from short term chemostat perturbation experiments. We approximate the time constant of each metabolite pool by their turn-over time and classify the pools accordingly into two groups: fast and slow pools. We performed a priori model reduction, neglecting the dynamic term of the fast pools. By making use of the linlog approximative kinetics, we obtained a general explicit solution for the fast pools in terms of the slow pools by elaborating the degenerate algebraic system resulting from model reduction. The obtained relations yielded also analytical relations between a subset of kinetic parameters. These relations also allow to realize an analytical model reduction using lumped reaction kinetics. After solving these theoretical identifiability problems and performing model reduction, we carried out a Monte Carlo approach to study the practical identifiability problems. We illustrated the methodology on model reduction and theoretical/practical identifiability analysis on an example system representing the glycolysis in Saccharomyces cerevisiae cells.  相似文献   
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In this study phytochemical compounds and antioxidant capacity, cytotoxic, antimicrobial and anti-biofilm activities of hydroethanolic extracts of five Cistus species (C. creticus L., C. laurifolius L., C. monspeliensis L., C. parviflorus Lam. and C. salviifolius L.) distributed in Turkey were investigated. (+)-catechin, epigallocatechin gallate, quercetin-3-O-rutinoside, quercetin-3-O-glucoside, kaempferol-3-O-glucoside, luteolin were detected in different amounts. Strongest antioxidant capacities were observed with C. creticus, and C. parvifolius (0.476 and 0.452, respectively). Minimum inhibitory concentrations (MIC) of the extracts were determined between 32 and 128 μg/mL against different bacteria and Candida strains. C. monspeliensis and C. laurifolius extracts were inhibited the biofilm production levels of three Gram-negative bacteria (E. coli, S. enterica, P. aeruginosa), two Gram-positive bacteria (S. aureus, B. subtilis) and three Candida strains (C. albicans, C. parapsilosis, C. krusei). C. creticus extract showed strongest cytotoxic activity against human breast adenocarcinoma (MCF-7) and prostate cell lines (PC-3) (IC50: 14.04±2.78 μg/mL and 34.04±2.74 μg/mL, respectively) among all plants tested.  相似文献   
70.
Applied Microbiology and Biotechnology - Levulinic acid was esterified with methanol, ethanol, and 1-butanol with the final goal to predict the maximum yield of these equilibrium-limited reactions...  相似文献   
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