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81.
Thor Peter; Cervetto Guillermo; Besiktepe Sengul; Ribera-Maycas Encarna; Tang Kam W.; Dam Hans G. 《Journal of plankton research》2002,24(4):293-300
Previous studies have shown that the two green algae Tetraselmissp. (Prasinophyceae) and Dunaliella tertiolecta (Chlorophyceae)induce high and low egg production rates in Acartia tonsa. Theprimary goal of the present study was to investigate if thisis attributable to differences in the specific dynamic action(SDA) of the two diets. Secondly, we wanted to investigate ifany qualitative differences in the incorporation of nutritionalconstituents from the two diets are influencing SDA. The functionalresponse of ingestion was very different with the two diets.Ingestion of T. impellucida was relatively high even at lowfood concentrations with a maximum of 19 µg C ind-1 day-1.The functional response was more clearly sigmoidal on D. tertiolectawith a maximum of 7.3 µg C ind-1 day-1. The higher ingestionrate of T. impellucida also induced higher respiration rates.Maximum respiration rates were 3.0 nl O2 ind-1 min-1 on T. impellucidaand 1.5 nl O2 ind-1 min-1 onD. tertiolecta. This created significantlydifferent SDA coefficients: 0.19 on T. impellucida and 0.06on D. tertiolecta, which implies that the magnitude of SDA isstrongly influenced by the composition of the diet. The incorporationof carbon into lipids was significantly higher on D. tertiolecta.However, because of lack of longer chain fatty acids in D. tertiolectathe copepods did not benefit from this. Thus, the proportionof carbon allocated to egg lipids was much lower than when feedingon T. impellucida. Acartia tonsa incorporated relatively morecarbon into proteins when feeding on T. impellucida than onD. tertiolecta. Since protein synthesis is energetically verydemanding this is probably the reason for the higher SDA coefficientin those feeding on T. impellucida. 相似文献
82.
Abdurrahman Gumus Seoho Lee Syed S. Ahsan Kolbeinn Karlsson Richard Gabrielson Christopher G. Guglielmo David W. Winkler David Erickson 《PloS one》2015,10(4)
The metabolism of birds is finely tuned to their activities and environments, and thus research on avian systems can play an important role in understanding organismal responses to environmental changes. At present, however, the physiological monitoring of bird metabolism is limited by the inability to take real-time measurements of key metabolites during flight. In this study, we present an implantable biosensor system that can be used for continuous monitoring of uric acid levels of birds during various activities including flight. The system consists of a needle-type enzymatic biosensor for the amperometric detection of uric acid in interstitial fluids. A lightweight two-electrode potentiostat system drives the biosensor, reads the corresponding output current and wirelessly transfers the data or records to flash memory. We show how the device can be used to monitor, in real time, the effects of short-term flight and rest cycles on the uric acid levels of pigeons. In addition, we demonstrate that our device has the ability to measure uric acid level increase in homing pigeons while they fly freely. Successful application of the sensor in migratory birds could open up a new way of studying birds in flight which would lead to a better understanding of the ecology and biology of avian movements. 相似文献
83.
Ana Mustiana Jenny-Ann Toribio Muktasam Abdurrahman I. Wayan Suadnya Marta Hernandez-Jover Anak Agung Gde Putra Michael P. Ward 《PloS one》2015,10(5)
Although Indonesia has been rabies-infected since at least the 1880s, some islands remain rabies-free, such as Lombok. However, due to its adjacency to rabies-infected islands such as Bali and Flores, there is considerable risk of a rabies incursion. As part of a rabies risk assessment project, surveys were conducted to estimate the size of the dog population and to describe dog management practices of households belonging to different ethnic groups. A photographic-recapture method was employed and the number of unowned dogs was estimated. A total of 400 dog owning households were interviewed, 300 at an urban site and 100 at a rural site. The majority of the interviewed households belonged to the Balinese ethnic group. Owned dogs were more likely male, and non-pedigree or local breed. These households kept their dogs either fully restricted, semi-free roaming or free-roaming but full restriction was reported only at the urban site. Dog bite cases were reported to be higher at the urban site, and commonly affected children/young adults to 20 years old and males. A higher number of unowned dogs was observed at the urban site than at the rural site. Data generated within these surveys can inform rabies risk assessment models to quantify the probability of rabies being released into Lombok and resulting in the infection of the local dog population. The information gained is critical for efforts to educate dog owners about rabies, as a component of preparedness to prevent the establishment of rabies should an incursion occur. 相似文献
84.
Ji Young Kim Jihee Kim Yuri Ahn Eun Jung Lee Shinwon Hwang Abdurrahman Almurayshid Keedon Park Hwa‐Jee Chung Heung Jae Kim Si‐Hyung Lee Myung‐Shik Lee Sang Ho Oh 《Pigment cell & melanoma research》2020,33(3):403-415
Autophagy regulates cellular turnover by disassembling unnecessary or dysfunctional constituents. Recent studies demonstrated that autophagy and its regulators play a wide variety of roles in melanocyte biology. Activation of autophagy is known to induce melanogenesis and regulate melanosome biogenesis in melanocytes. Also, autophagy induction was reported to regulate physiologic skin color via melanosome degradation, although the downstream effectors are not yet clarified. To determine the role of autophagy as a melanosome degradation machinery, we administered several autophagy inducers in human keratinocytes and melanocytes. Our results showed that the synthetic autophagy inducer PTPD‐12 stimulated autophagic flux in human melanocytes and in keratinocytes containing transferred melanosomes. Increased autophagic flux led to melanosome degradation without affecting the expression of MITF. Furthermore, the color of cell pellets of both melanocytes and keratinocytes was visibly lightened. Inhibition of autophagic flux by chloroquine resulted in marked attenuation of PTPD‐12‐induced melanosome degradation, whereas the expression of melanogenesis pathway genes and proteins remained unaffected. Taken together, our results suggest that the modulation of autophagy can contribute to the regulation of melanocyte biology and skin pigmentation. 相似文献
85.
Severity of chronic obstructive pulmonary disease (COPD) exacerbation is associated with increased level of copper (Cu), zinc
(Zn), and lipid peroxidation (malodialdehyde, MDA). The aim of this study was to investigate the levels of lipid peroxidation,
Coenzyme Q10 (CoQ10), Zn, and Cu in the COPD exacerbations. Forty-five patients with COPD acute exacerbation and 45 healthy
smokers as control group were used in the study. Forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were
lower in exacerbation group than in control. C- reactive protein levels, white blood cell count, and sedimentation rate were
significantly (p < 0.001) higher in patients than in control. CoQ10 level and Cu/Zn ratio was significantly (p < 0.05) lower in patients than in control, although MDA, Cu, and Zn levels were significantly (p < 0.05) higher in patients than in control. Negative correlations were found among MDA, Cu, Zn, FEV1, and FVC values in exacerbation
and control subjects (p < 0.05). In conclusion, we observed that oxidative stress in the exacerbation period of COPD patients was increased. The
decrease in CoQ10 level and Cu/Zn ratio and elevation in Cu and Zn levels observed in the patients probably result from the
defense response of organism and are mediated by inflammatory-like substances. 相似文献
86.
Chemical composition and fumigant toxicity of some essential oils against Ephestia kuehniella 总被引:1,自引:0,他引:1
The chemical constituents of some essential oils extracted from aromatic plants (savory, Satureja thymbra L.; Turkish oregano, Origanum onites L.; myrtle, Myrtus communis L.; marjoram, Origanum majorana L.; laurel, Laurus nobilis L.; lemon, Citrus limon L.; sticky goosefoot, Chenopodium botrys L.; and tansy, Tanecetum armenum [DC.] Suchultz Bip.) were analyzed by gas chromatography-mass spectrometry. Fumigant toxicity of volatile compounds was tested against Mediterranean flour moth, Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae), eggs and adults. Percentage of mortality and longevity of E. kuehniella adults were estimated after essential oil treatments. LC50 and LC99 values were determined for each exposure time for each essential oil. Marjoram and lemon oils were the most effective of all the essential oils tested. The major components were linalool, 1.8-cineole, citral, 2-(4a.8-dimethyl-1.2.3.4.4a.5.6.7-octahydro-naphthalen-2-yl)-prop-2-en-l-ol, and p-cymene for marjoram, laurel, lemon, goosefoot, and tansy, respectively. The LC50 and LC99 values were estimated as 3.27 and 5.13 microl liter(-1) air for marjoram and 4.05 and 5.57 microl liter(-1) air for lemon essential oils at the longest exposure time. Decreasing longevity effect of marjoram and lemon was more prominent compared with other essential oils. We suggest that essential oils obtained from certain aromatic plants have potential as fumigants for stored product pests. 相似文献
87.
Dayan K Keser A Konyalioglu S Erturk M Aydin F Sengul G Dagci T 《Life sciences》2012,90(9-10):360-364
AimsAlthough hyperbaric oxygen (HBO) treatment following spinal cord injury (SCI) have been studied in terms of neurological function and tissue histology, there is a limited number studies on spinal cord tissue enzyme levels.Main methodsThe effect of HBO treatment in SCI was investigated by measuring superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), nitric oxide synthase (NOS) and nitric oxide (NO) activity in the injured tissue. SCI was induced by applying an aneurysm clip extradurally at the level of T9-T11 vertebrae. Preoperative HBO (preopHBO) treatment was applied for 5 days and postoperative HBO (postopHBO) for 7 days.Key findingsIn the preopHBO group, a significant decrease was observed in NOS and NO compared to the SCI group. There was a decrease in SOD, NOS and NO in the postopHBO group when compared to the SCI group. In the pre–postHBO group SOD, GPx, NOS and NO decreased significantly. There was a decrease in SOD in postopHBO compared to preopHBO. In the prepostopHBO, SOD decreased significantly compared to that in the preopHBO group. The prepostopHBO presented a significant decrease in GPx compared to postopHBO (p < 0.05 for all parameters). No significant difference was observed for catalase for all groups. Significant improvement was found in BBB scores for both postopHBO and prepostHBO groups when compared to the SCI group (p < 0.05).SignificanceHBO treatment was found to be beneficial following SCI in terms of biochemical parameters and functional recovery in the postoperative period. 相似文献
88.
Ramazan Ceylan Sengul Uysal Veli Ilhan Abdurrahman Aktumsek Ali Kandemir 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):983-990
We investigated the antioxidant and enzyme inhibitory activities and chemical composition of the hydro-distilled essential oil (0.35% yield) from aerial parts of Thymus spathulifolius. Antioxidant capacity of the oil was assessed by different methods including free radical scavenging (DPPH and ABTS), reducing power (FRAP and CUPRAC) and phosphomolybdenum assay. Inhibitory activities were analyzed against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase, α-glucosidase, and tyrosinase. Twenty-one constituents were identified representing 97.2% of the total oil with thymol (50.5%), borneol (16.7%) and carvacrol (7.7%) as the major components. The essential oil exhibited good antioxidant activity with IC50 values of 3.82 and 0.22?mg/mL determined by free radical scavenging DPPH and ABTS, respectively. EC50 values of FRAP and CUPRAC were found to be 0.12 and 0.34?mg/mL, respectively. The results of the present study support the uses of T. spathulifolius essential oil as a source of natural antioxidants and bioactivities for functional foods and phytomedicines. 相似文献
89.
Osman Yaln Ylmaz Ali Kavgac Orhan Sevgi Erdal
rtel Hüseyin Bar Tecimen Abdurrahman obanolu smet Yeil 《Ecology and evolution》2019,9(22):12802-12812
Better understanding of the competitive interaction at the early development stages of the stand is crucial to help schedule silvicultural treatments for young stands and for the better management of the future stands. We used scale‐dependent analysis to improve our understanding of sapling dynamics in the pure Taurus cedar (Cedrus libani A. Rich.) stands in Southern Turkey. Using data from nine plots established at the western Taurus Mountains, diameter, height, and crown radii of saplings were compared, and spatial point pattern analyses were performed. We found significant differences for the mean diameter and height, and crown radii of saplings among the plots. Univariate pair correlation function showed that sapling pattern was regular only at small scales (r < 0.4 m) but was predominantly random. Bivariate pair correlation function revealed no evidence of spatial interaction between tall saplings and short saplings. Univariate mark correlation function revealed that strong intraspecific competition was detected at small scales (up to 0.55 m). This distance is reasonable for the juvenile age tending of Taurus cedar saplings and should be under consideration during silvicultural treatments to use the site productivity more efficiently. 相似文献
90.
Altınay Perendeci Sever Arslan Abdurrahman Tanyolaç Serdar S. Çelebi 《Bioresource technology》2009,100(20):4579-4587
A conceptual neural fuzzy model based on adaptive-network based fuzzy inference system, ANFIS, was proposed using available input on-line and off-line operational variables for a sugar factory anaerobic wastewater treatment plant operating under unsteady state to estimate the effluent chemical oxygen demand, COD. The predictive power of the developed model was improved as a new approach by adding the phase vector and the recent values of COD up to 5–10 days, longer than overall retention time of wastewater in the system. History of last 10 days for COD effluent with two-valued phase vector in the input variable matrix including all parameters had more predictive power. History of 7 days with two-valued phase vector in the matrix comprised of only on-line variables yielded fairly well estimations. The developed ANFIS model with phase vector and history extension has been able to adequately represent the behavior of the treatment system. 相似文献