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101.
A fluorescence method was employed for studying the drying and swelling of PAAm–κC composite gels, which were formed from acrylamide (AAm) and N, N’- methylenebisacrylamide (BIS) with various κ–carrageenan (κC) contents by free radical crosslinking copolymerization in water. Composite gels were prepared at 80 °C with pyranine (Py) as a fluorescence probe. Scattered light, Isc, and fluorescence emission intensities, Iem, were monitored during drying and swelling of these gels. The fluorescence intensity of pyranine increased and decreased as drying and swelling time are increased, respectively, for all gel samples. The Stern–Volmer equation combined with moving boundary and Li-Tanaka models were used to explain the behavior of Iem during drying and swelling processes respectively. It is found that the desorption coefficient Dd decreased as κC contents were increased for a given temperature during drying. However, the cooperative diffusion coefficient, Ds presented exactly the opposite case. Conventional gravimetrical and volumetric experiments were also carried out during drying and swelling of PAAm–κC composite gels. It was observed that Dd and Ds values measured with the fluorescence method were found to be much larger than they were measured with the conventional methods.  相似文献   
102.
103.
Symptoms resembling those associated with phytoplasma presence were observed in pomegranate (Punica granatum L.) trees in June 2012 in the Aegean Region of Turkey (Ayd?n province). The trees exhibiting yellowing, reduced vigour, deformations and reddening of the leaves and die‐back symptoms were analysed to verify phytoplasma presence. Total nucleic acids were extracted from fresh leaf midribs and phloem tissue from young branches of ten symptomatic and five asymptomatic plants. Nested polymerase chain reaction assays using universal phytoplasma‐specific 16S rRNA and tuf gene primers were performed. Amplicons were digested with Tru1I, Tsp509I and HhaI restriction enzymes, according to the primer pair employed. The phytoplasma profiles were identical to each other and to aster yellows (16SrI‐B) strain when digestion was carried out on 16Sr(I)F1/R1 amplicons. However, one of the samples showed mixed profiles indicating that 16SrI‐B and 16SrXII‐A phytoplasmas were present when M1/M2 amplicons were digested, the reamplification of this sample with tuf cocktail primers allowed to verify the presence of a 16SrXII‐A profile. One pomegranate aster yellows strain AY‐PG from 16S rRNA gene and the 16SrXII‐A amplicon from tuf gene designed strain STOL‐PG were directly sequenced and deposited in GenBank under the Accession Numbers KJ818293 and KP161063, respectively. To our knowledge, this is the first report of 16SrI‐B and 16SrXII‐A phytoplasmas in pomegranate trees.  相似文献   
104.
Venous thrombosis is a significant cause of morbidity and mortality in patients with malignancies. We aimed to investigate the association between prothrombotic gene polymorphisms detected in lung cancer cases and deep venous thrombosis (DVT). Totally 66 patients with an established diagnosis of lung cancer, of which 33 developed DVT, were enrolled. Multiplex PCR technique and reverse hybridization strip assay were performed on DNA extracted from peripheral blood, in order to analyze prothrombin G20210A, factor V G1691A, methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, angiotensin converting enzyme (ACE), plasminogen activator inhibitor-1 (PAI-1), and glycoprotein IIIa (Gp IIIa) gene mutations. Among prothrombotic gene polymorphisms investigated in this study, the commonest ones were PAI-1 4G/5G (56% heterozygous, 39% homozygous) and ACE gene mutations (58% heterozygous, 17% homozygous). The presence of homozygous MTHFR A1298C mutation was significantly associated with DVT (P = 0.020). Comparing the lung cancer patients with and without DVT, only MTHFR A1298C gene polymorphism differed significantly (P = 0.040). We determined a higher rate of prothrombotic gene mutations in lung cancer patients who developed DVT. However, statistical significance was achieved only for MTHFR A1298C gene mutation. Therefore, nongenetic factors for disturbance of hemostatic metabolism should also be considered in lung cancer patients.  相似文献   
105.
Understanding farmers’ attitudes and responses to agricultural risks is important for designing financial support services and effective extension activities. Risk attitudes of farmers are also one of the critical barriers for conversion to organic agriculture. Few studies have been conducted to explore and compare risk perceptions between organic and conventional farmers. The purposes of this research were to elicit and compare the risk attitudes of organic and conventional Turkish hazelnut producers and to determine the barriers additional to their risk attitudes toward conversion to organic agriculture in the Terme district of Samsun, Turkey. The Equally Likely Certainty Equivalent (ELCE) model was used to elicit responses from producers. The data used in this study were collected by using a structured questionnaire administered to both 64 randomly selected conventional hazelnut producers and all organic hazelnut producers (39) in the research area. Research results revealed that organic hazelnut producers were less risk averse than conventional producers. It was also found that the variables of education level of operators, farm income, total assets, time allocated outside the farm, farm land area, size of hazelnut orchard, number of hazelnut plots, and total information score were other barriers for conversion to organic hazelnut production, in addition to the producers’ risk attitudes. Providing better extension services and farmers’ training activities relating to organic agriculture and land consolidation, focusing on raising the educational level of producers, facilitating producers with greater access to credit to increase farm land and to enhance farm assets are factors that may accelerate the process of conversion to organic hazelnut production.  相似文献   
106.
Five new phenyl dihydroisocoumarin glycosides ( 1 – 5 ) and two known compounds ( 6 – 7 ) were identified from the butanol fraction of Scorzonera longiana. The structures of 1 – 7 were elucidated based on spectroscopic methods. Antimicrobial, antitubercular, and antifungal evaluation of compounds 1 – 7 were carried out using the microdilution method against nine microorganisms. Compound 1 was active only against Mycobacterium smegmatis (Ms) with a MIC value of 14.84 μg/mL. All tested compounds ( 1 – 7 ) were active against Ms but only compounds 3–7 were active against fungi (C. albicans, S. cerevisiae) with MIC values of 25.0–125 μg/mL. In addition, molecular docking studies were conducted against Ms DprE1 (PDB ID: 4F4Q), Mycobacterium tuberculosis (Mbt) DprE1 (PDB ID: 6HEZ), and arabinosyltransferase C (EmbC, PDB ID: 7BVE) enzymes. Compounds 2 , 5 , and 7 are the most effective Ms 4F4Q inhibitors. Compound 4 was the most promising inhibitory activity on Mbt DprE with the lowest binding energy of −9,9 kcal/mol.  相似文献   
107.
Endotoxin tolerance is defined as a hyporesponsiveness state to a second stimulation with lipopolysaccharide (LPS). This refractory state is primarily associated with an attenuated cytokine production. Whether this down-regulation of cytokine production results in an increased susceptibility to infection remains a matter of controversy. The aim of this study was to investigate the resistance of tolerant mice to a subsequent bacterial infection and the role of bacterial immunomodulator CANTASTIM (CS) in this experimental model. We have shown that the LPS-tolerant mice (intraperitoneally inoculated with LPS Salmonella typhimurium 10 microg/mouse, daily for two days) were protected against a challenge with Pseudomonas aeruginosa (LD 100) administered 24 h later. On the contrary, when the animals were challenged 1 h after the last LPS injection, they did not survive. However if these animals were pre-treated with CS 3 days before LPS treatment, they became resistant to a subsequent bacterial challenge. More interestingly, if the treatment with LPS was substituted with CS (same schedule, route of administration and doses) there was a significant increase in the survival of mice challenged with Pseudomonas aeruginosa after either 1 h or 24 h. In this case, the increase in the rate of survival was correlated with an enhanced production of IL-10 in the peritoneal cavities of CS treated mice as compared to LPS treated mice.  相似文献   
108.
A review of 35 cases of asymmetric crying facies   总被引:2,自引:0,他引:2  
A review of 35 cases of asymmetric crying facies: Congenital asymmetric crying facies (ACF) is caused by congenital hypoplasia or agenesis of the depressor anguli oris muscle (DAOM) on one side of the mouth. It is well known that this anomaly is frequently associated with cardiovascular, head and neck, musculoskeletal, respiratory, gastrointestinal, central nervous system, and genitourinary anomalies. In this article we report 35 ACF patients (28 children and 7 adults) and found additional abnormalities in 16 of them (i.e. 45%). The abnormalities were cerebral and cerebellar atrophy, mega-cisterna magna, mental motor retardation, convulsions, corpus callosum dysgenesis, cranial bone defect, dermoid cyst, spina bifida occulta, hypertelorism, micrognatia, retrognatia, hemangioma on the lower lip, short frenulum, cleft palate, low-set ears, preauricular tag, mild facial hypoplasia, sternal cleft, congenital heart defect, renal hypoplasia, vesicoureteral reflux, hypertrophic osteoarthropathy, congenital joint contractures, congenital hip dislocation, polydactyly, and umbilical and inguinal hernia. Besides these, one infant was born to a diabetic mother, and had atrial septal defect and the four other children had 4p deletion, Klinefelter syndrome, isolated CD4 deficiency and Treacher-Collins like facial appearance, respectively Although many of these abnormalities were reported in association with ACF, cerebellar atrophy, sternal cleft, cranial bone defect, infant of diabetic mother, 4p deletion, Klinefelter syndrome, isolated CD4 deficiency and Treacher-Collins like facial appearance were not previously published.  相似文献   
109.
The conformational states of two peptide sequences that bind to staphylococcal enterotoxin B are sampled by replica exchange molecular dynamic (REMD) simulations in explicit water. REMD simulations were treated with 52 replicas in the range of 280–501 K for both peptides. The conformational ensembles of both peptides are dominated by random coil, bend and turn structures with a small amount of helical structures for each temperature. In addition, while an insignificant presence of β-bridge structures were observed for both peptides, the β-sheet structure was observed only for peptide 3. The results obtained from simulations at 300 K are consistent with the experimental results obtained from circular dichroism spectroscopy. From the analysis of REMD results, we also calculated hydrophobic and hydrophilic solvent accessible surface areas for both peptides, and it was observed that the hydrophobic segments of the peptides tend to form bend or turn structures. Moreover, the free-energy landscapes of both peptides were obtained by principal component analysis to understand how the secondary structural properties change according to their complex space. From the free-energy analysis, we have found several minima for both peptides at decreased temperature. For these obvious minima of both peptides, it was observed that the random coil, bend and turn structures are still dominant and the helix, β-bridge or β-sheet structures can appear or disappear with respect to minima. On the other hand, when we compare the results of REMD with conventional MD simulations for these peptides, the configurations of peptide 3 might be trapped in energy minima during the conventional MD simulations. Hence, it can be said that the REMD simulations have provided a sufficiently high sampling efficiency.  相似文献   
110.
In the present study, the effect of systemically administered vasoactive intestinal peptide (VIP) (25 ng/kg i.p.) was investigated on drug-induced rotational behavior, extra-cellular dopamine levels and histology of corpus striatum in a 6-hydroxydopamine (6-OHDA)-induced rat model of Parkinson's disease. After 15 days of 6-OHDA lesion, apomorphine-induced (0.05 mg/kg s.c.) rotational behavior of the animals significantly increased and extra-cellular dopamine levels of corpus striatum were significantly reduced. VIP reversed the rotational deficits but did not alter the decrease in striatal dopamine levels. On the other hand, histological data indicate that VIP significantly reduced neuronal death and demyelination. Electron microscopic appearance of mast cells showed ultra-structural variety between VIP-treated and 6-OHDA lesioned groups. VIP activates mast cells without any evidence of typical exocytosis, and possibly mast cells could participate in neuroprotection. Our results suggest that systemically administered VIP can attenuate the motor response changes, neuronal cell death, and myelin sheet loss characteristically associated with 12 microg 6-OHDA administration into the rat striatum. Brain mast cells seem to participate in neuronal protection. Possibly, protective cues could be produced by brain mast cells.  相似文献   
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