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61.
62.
Crespo JF Retzek M Foetisch K Sierra-Maestro E Cid-Sanchez AB Pascual CY Conti A Feliu A Rodriguez J Vieths S Scheurer S 《Molecular nutrition & food research》2006,50(3):282-290
Oranges are clinically relevant allergenic foods. To date, orange allergens have not been characterized in detail. The study is aimed at analyzing the sensitization profile in orange-sensitized subjects with and without clinical allergy, and to identify orange allergens. Fifty-six sensitized subjects with self-reported reactions to orange were grouped into reactors (anaphylaxis or multiple episodes of immediate reactions and/or positive challenge tests) and non-reactors (negative open food challenge tests). Allergens were characterized by IgE immunoblotting, N-terminal sequencing, IgE-inhibition assays, and mediator release assays were performed to determine the allergenic potency of orange profilin. Of 56 subjects, 23 were classified as orange allergic showing mainly an oral allergy syndrome. Of 23 subjects classified as orange allergic, 22 were sensitized to profilin, Cit s 2. In patients with mono-sensitization to profilin in vitro histamine releases up to 75% from basophils were induced using orange extract and purified plant profilins. Of the allergic patients 78% were sensitized to germin-like protein, Cit s 1. Both allergens showed retained IgE reactivity in heat-processed orange juice. Interestingly, subjects with and without clinical allergy showed a comparable sensitization profile. Profilin and germin-like proteins are major orange allergens. The potential clinical relevance of orange profilin was indicated by its strong capacity to release histamine from basophils. However, a predominant sensitization to both allergens in subjects without symptoms also indicates a high frequency of clinically insignificant sensitization. 相似文献
63.
Methane is an important climate gas contributing significantly to global warming. A large part of the anthropogenic emissions of methane comes from landfills. Due to the biogenic origin of these emissions and the inhomogeneous characteristics of landfills and their soil cover, these emissions show large spatial variation. Thus, development of reliable and cost-effective methods for measurements of these emissions is an important task and a challenge to the scientific community. Traditionally, field chamber methods have been used but also different area integrating methods based on downwind plume measurements. These measurements have been supported by meteorological data either directly from local measurements or by controlled release of tracer gas from the landfill providing the dispersion characteristics of the plume. In this paperwe describe a method,the Time Correlation Tracer method, combining controlled tracer gas release from the landfill with time-resolved concentration measurements downwind the landfill using FTIR absorption spectroscopy. The method has been tested and used on measurements at a landfill in southern Sweden over the past 1.5 years. The method has proven to be a usable method for measurements of total methane emission from landfills, and under favorable meteorological conditions we estimate an achievable accuracy of 15-30%. The real time analysis capability of the FTIR makes it possible to judge the success of the measurement already on site and to decide whether more measurements are necessary. The measurement strategy is relatively simple and straightforward, and one person can make a measurement from a medium sized landfill (1-4 ha) within a few days to a week depending on the meteorological situation. 相似文献
64.
Markström E Svensson ECh Shao R Svanberg B Billig H 《Reproduction (Cambridge, England)》2002,123(1):23-30
Only a minute fraction of the ovarian follicles present in a fetal ovary will complete the path to ovulation. Most of the follicles will undergo atresia, a hormonally controlled apoptotic process. Apoptosis occurs at each stage of follicular development and there is a marked reduction in the number of follicles present at birth. Stage-dependent mechanisms of follicle survival can be postulated to achieve co-ordinated development, leading to ovulation of a small fraction of follicles. Indeed, hormone and growth factor regulation of follicular atresia is stage-specific. This short review considers the factors that promote survival of ovarian follicles throughout development, including endocrine, locally produced and intracellular mediators, as exemplified mainly by follicular development in rodents. In primordial follicles, oocyte apoptosis is considered to be the cause of subsequent follicle degeneration. In slow-growing preantral follicles, FSH is not a survival factor, but some locally produced growth factors are. Progression to the antral follicle stage is probably the most critical stage of follicle development in vivo, and FSH is a major survival factor at this stage. In addition, insulin-like growth factor I and interleukin 1beta are potent survival factors for cultured rat follicles at the antral stage. Preovulatory follicles express receptors for LH, and both of the gonadotrophins are survival factors at this stage. Relatively little is known about the period between the LH surge and ovulation; however, it has been suggested that at this stage progesterone acts as a survival factor. 相似文献
65.
The effect of the reaction temperature and the metals of an iron subgroup on the thermo-chemical treatment of titanium carbide with a chlorine gas and their influence on the carbon structure obtained thereby was studied. Different analytical methods such as porosity measurements, X-ray diffraction spectrometry and a high-resolution electron microscopy revealed the catalytic behaviour of the above-mentioned metals, which appeared to support the formation of graphitised carbon at much lower temperatures compared to those needed for the ordinary thermo-chemical chlorination of titanium carbide. 相似文献
66.
The aim of the present study was to investigate the influence of partially hydrogenated vegetable and marine oils on membrane
composition and function of liver microsomes and platelets with particular reference to the metabolism of linoleic acid and
the production of arachidonic acid metabolites. Four groups of male weanling rats were fed linoleic acid supplemented diets
containing 20% (w/w) of partially hydrogenated low erucic acid rapeseed oil (HLRSO), partially hydrogenated herring oil (HHO),
olive oil (OO) and trierucin + triolein (TE) for 10 weeks. An additional two groups were fed partially hydrogenated low erucic
acid rapeseed oil and partially hydrogenated herring oil without linoleic acid supplementation (HLRSO- and HHO-, respectively).
Substantial amounts oftrans fatty acids were incorporated into liver microsomes (12.6% in group HLRSO) and platelets (7.0% in group HLRSO-). This incorporation
was not dependent on the dietary linoleic acid level. Hepatic microsomal Δ5-desaturase activity was significantly increased after HLRSO feeding compared to OO feeding. Δ6-Desaturase activity did not vary in the linoleic acid supplemented groups. Both Δ5- and Δ6-desaturase activities were significantly increased in groups without linoleic acid supplementation.
Docosenoic acid was incorporated into platelet phospholipids in contrast to liver microsomes. In the platelet, docosenoic
acid seemed to have a special preference for phosphatidylserine. Very small amounts were incorporated into platelet phosphatidylinositol.
Feeding diets HLRSO, HHO and OO did not influence rat platelet cyclooxygenase or 12-lipoxygenase activity. Platelets from
rats fed TE, however, produced significantly less 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) than platelets from
rats fed OO. Feeding of HLRSO- and HHO- resulted in a significantly diminished production of the arachidonic acid metabolites
12-HETE, 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) and 6-keto-prostaglandin F1α in stimulated platelets and aorta. Thus, high dietary levels oftrans isomers of monoenoic acids do not interfere with platelet cyclooxygenase or lipoxygenase activity provided sufficient amounts
of linoleic acid are available. 相似文献
67.
Adeel Nasir Peter Rolf Richter Aude Le Bail Viktor Daiker Julia Stoltze Binod Prasad Sebastian Michael Strauch Michael Lebert 《International journal of molecular sciences》2022,23(5)
Euglena gracilis is a photosynthetic flagellate. To acquire a suitable position in its surrounding aquatic environment, it exploits light and gravity primarily as environmental cues. Several physiological studies have indicated a fine-tuned relationship between gravity sensing (gravitaxis) and light sensing in E. gracilis. However, the underlying molecular mechanism is largely unknown. The photoreceptor photoactivated adenylyl cyclase (PAC) has been studied for over a decade. Nevertheless, no direct/indirect interaction partner (upstream/downstream) has been reported for PAC. It has been shown that a specific protein, kinase A (PKA), showed to be involved in phototaxis and gravitaxis. The current study reports the localization of the specific PKA and its relationship with PAC. 相似文献
68.
Anna Carla Culla Corina Vater Xinggui Tian Julia Bolte Tilman Ahlfeld Henriette Bretschneider Alexander Pape Stuart B. Goodman Michael Gelinsky Stefan Zwingenberger 《International journal of molecular sciences》2022,23(6)
To treat critical-size bone defects, composite materials and tissue-engineered bone grafts play important roles in bone repair materials. The purpose of this study was to investigate the bone regenerative potential of hybrid scaffolds consisting of macroporous calcium phosphate cement (CPC) and microporous mineralized collagen matrix (MCM). Hybrid scaffolds were synthetized by 3D plotting CPC and then filling with MCM (MCM-CPC group) and implanted into a 5 mm critical size femoral defect in rats. Defects left empty (control group) as well as defects treated with scaffolds made of CPC only (CPC group) and MCM only (MCM group) served as controls. Eight weeks after surgery, micro-computed tomography scans and histological analysis were performed to analyze the newly formed bone, the degree of defect healing and the activity of osteoclasts. Mechanical stability was tested by 3-point-bending of the explanted femora. Compared with the other groups, more newly formed bone was found within MCM-CPC scaffolds. The new bone tissue had a clamp-like structure which was fully connected to the hybrid scaffolds and thereby enhanced the biomechanical strength. Together, the biomimetic hybrid MCM-CPC scaffolds enhanced bone defect healing by improved osseointegration and their differentiated degradation provides spatial effects in the process of critical-bone defect healing. 相似文献
69.
New developments at JET in diagnostics, real-time control, data acquisition and information retrieval with potential application to ITER 总被引:1,自引:0,他引:1
J. Vega A. Murari G. de Arcas M. Riva J. Svensson 《Fusion Engineering and Design》2009,84(12):2136-2144
In magnetic confinement fusion, the operation of next generation devices will be significantly different compared to present day machines. The duration length of the discharges will require abandoning the traditional paradigm of processing and storing the data after the shot. In fact most information will have to be made available in real-time. The significant issues of machine protection will require more sophisticated and at the same time more robust feedback control schemes. Another very important issue emerged in the last years of JET operation, and which is expected to become more severe in ITER, is the large amount of data to be analysed, which cannot be handled in the most efficient way with traditional methods.In order to prepare for the operation of ITER, some tests are being performed at JET. The capacity of the real-time network has increased in the last years, and many more systems, mainly diagnostics have been connected to it in order to test their reliability and to assess the quality of the information they can provide for feedback control. To reduce the amount of data, a prototype of real-time adaptive data acquisition techniques is being implemented, to adjust the acquisition frequency to the time resolution of the phenomena to be analysed in the plasma. Lossless data compression techniques have been refined and various intelligent signal processing methods have already been implemented to allow an easier and more objective first screening of the data. To allow scientists from wide and diffuse communities to participate in the scientific and technical programme, various innovative tools for remote participation and experimentation are also being actively investigated. 相似文献
70.