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1.
This study deals with the formulation of natural drugs into hydrogels. For the first time, compounds from the sage essential oil were formulated into chitosan hydrogels. A sample preparation procedure for hydrophobic volatile analytes present in a hydrophilic water matrix along with an analytical method based on the gas chromatography coupled with the mass spectrometry (GC-MS) was developed and applied for the evaluation of the identity and quantity of essential oil components in the hydrogels and saline samples. The experimental results revealed that the chitosan hydrogels are suitable for the formulation of sage essential oil. The monoterpene release can be effectively controlled by both chitosan and caffeine concentration in the hydrogels. Permeation experiment, based on a hydrogel with the optimized composition [3.5% (w/w) sage essential oil, 2.0% (w/w) caffeine, 2.5% (w/w) chitosan and 0.1% (w/w) Tween-80] in donor compartment, saline solution in acceptor compartment, and semi-permeable cellophane membrane, demonstrated the useful permeation selectivity. Here, (according to lipophilicity) an enhanced permeation of the bicyclic monoterpenes with antiflogistic and antiseptic properties (eucalyptol, camphor and borneol) and, at the same time, suppressed permeation of toxic thujone (not exceeding its permitted applicable concentration) was observed. These properties highlight the pharmaceutical importance of the developed chitosan hydrogel formulating sage essential oil in the dermal applications.  相似文献   
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Castor oil is a non‐traditional raw material for the preparation of methyl and ethyl esters of higher fatty acids as alternative fuels for diesel engines. Castor oil contains ricinoleic acid (12‐hydroxy octadecene acid) with a major share of about 90%. The article presents the parameters of castor oil‐based methyl esters (COME) and ethyl esters (COEE) defined by the standard EN 14 214. The densities of COME and COEE are higher than the limit defined by the standard EN 14 214. The viscosities are more than twice as high as the limit value. The cetane numbers are lower than defined by the standard EN 14 214. For the remaining parameters, COME and COEE meet, in principle, the standard EN 14 214. The presence of the free hydroxyl group has virtually no effect on the values of such parameters as carbon residue, filterability at low temperatures and oxidation stability, for which some influence was expected. The physicochemical parameters of the castor oil esters are discussed in comparison to the analogous esters of high‐oleic sunflower oil, which contain about 80% of oleic acid. Both the methyl and ethyl esters of high‐oleic sunflower oil meet the standard EN 14 214 in all prescribed parameters.  相似文献   
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Mitochondrial bioenergetics reprogramming is an essential response of cells to stress. Platelets, an accessible source of mitochondria, have a crucial role in cancer development; however, the platelet mitochondrial function has not been studied in urothelial carcinoma (UC) patients. A total of 15 patients with UC and 15 healthy controls were included in the study. Parameters of platelet mitochondrial respiration were evaluated using the high-resolution respirometry method, and the selected antioxidant levels were determined by HPLC. In addition, oxidative stress was evaluated by the thiobarbituric acid reactive substances (TBARS) concentration in plasma. We demonstrated deficient platelet mitochondrial respiratory chain functions, oxidative phosphorylation (OXPHOS), and electron transfer (ET) capacity with complex I (CI)-linked substrates, and reduced the endogenous platelet coenzyme Q10 (CoQ10) concentration in UC patients. The activity of citrate synthase was decreased in UC patients vs. controls (p = 0.0191). γ-tocopherol, α-tocopherol in platelets, and β-carotene in plasma were significantly lower in UC patients (p = 0.0019; p = 0.02; p = 0.0387, respectively), whereas the plasma concentration of TBARS was increased (p = 0.0022) vs. controls. The changes in platelet mitochondrial bioenergetics are consistent with cell metabolism reprogramming in UC patients. We suppose that increased oxidative stress, decreased OXPHOS, and a reduced platelet endogenous CoQ10 level can contribute to the reprogramming of platelet mitochondrial OXPHOS toward the activation of glycolysis. The impaired mitochondrial function can contribute to increased oxidative stress by triggering the reverse electron transport from the CoQ10 cycle (Q-junction) to CI.  相似文献   
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A single electroconvulsive shock (ECS) or a sham ECS was administered to male 3-4-month-old Wistar rats 1, 2, and 4 h before training in an inhibitory avoidance test and in cued classical fear conditioning (measured by means of freezing time in a new environment). ECS impaired inhibitory avoidance at all times and, at 1 or 2 h before training, reduced freezing time before and after re-presentation of the ECS. These results are interpreted as a transient conditioned stimulus (CS)-induced anxiolytic or analgesic effect lasting about 2 h after a single treatment, in addition to the known amnesic effect of the stimulus. This suggests that the effect of anterograde learning impairment is demonstrated unequivocally only when the analgesic/anxiolytic effect is over (about 4 h after ECS administration) and that this impairment of learning is selective, affecting inhibitory avoidance but not classical fear conditioning to a discrete stimulus.  相似文献   
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Polymer composites (PCs) with a polyurethane (PU) matrix filled with magnetic filler (MnZn ferrite) and hybrid polymer composites (HPCs) consisting of this magnetic filler and various types of conductive fillers (carbon black, carbon fibers, aluminum powder, polypyrrole) are prepared. The matrix structure of a HPC is formed (i) by a polymer filled with conductive filler, which forms the skeleton of an infinite cluster, and (ii) by ferrite particles that are larger than conductive particles. Thus, an HPC represents an ensemble of ferrite particles each of which is surrounded by a conductive medium and can be considered as a “core–shell” structure. The development of a core–shell structure is evidenced by the lower electric percolation threshold in an HPC compared with that in PU filled with conductive filler. Magnetic and dielectric spectra of PCs and HPCs are studied in the frequency range from 1 MHz to 10 GHz. Hybrid systems exhibit a considerable enhancement of magnetic losses compared with PCs. The enhancement of magnetic losses in HPCs is due to the conduction currents that are induced in the conductive shell by a microwave magnetic field.  相似文献   
8.
OBJECTIVE: The objective of this retrospective study was to determine if groin radiation was superior to no therapy in patients with small vulvar cancer with not palpable or not suspicious inguinal lymph nodes (T1, N0-N1). METHODS: From 1974 to 1990, 135 patients with invasive T1, NO-1 vulvar cancer underwent radical vulvectomy with hot knife, groin nodes were left in situ. In 65 patients vulvectomy was followed by inguinofemoral irradiation: 70 patients had none. There were more cases with clitoris carcinoma (p < 0.04) in the group with groin irradiation but no other significant difference in prognostic factors was found. RESULTS: The actuarial 5-year survival was 93.7% with groin irradiation versus 92.4% without lymph node therapy. Inguinal relapses occurred in only 4.6% of cases with groin irradiation versus 10% without lymph node treatment (n.s.). CONCLUSIONS: Radiation therapy to the groin seems to reduce groin relapses in early vulvar cancer.  相似文献   
9.
Steam-explosion pretreatment allows lowering of the natural resistance of plant material to subsequent biodegrading processes, such as anaerobic fermentation. This is achieved by a complex of cavitation forces that disintegrate rigid lignocellulose structures and liberate labile organic matter during a quick release of phytomass from a steam-pressurized reactor back to the atmospheric pressure. Hydrolyzing reactants or catalysts may increase the effect; however, the management of chemicals raises financial and environmental concerns. The current state of knowledge was reviewed to identify promising designs and reengineering that would enable subsequent transfer into the commercial scale in order to reverse the current trend of phytomass waste management – landfilling. In an effort to achieve profitability, it has been concluded that further development should focus on a deeper interconnection of the apparatus with associated technology units, reuse of waste heat from the subsequent biogas combustion, widening the range of processing parameters, reuse of nutrients, and utilization of the ballast organic matter.  相似文献   
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Livestock producers using public lands in the West were once concerned primarily with efficient systems for livestock production. Historically, this concept began in 1934 with the passage of the Taylor Grazing Act. Management activities on public lands continued to focus on sustainable livestock production until the 1970s, when the public began to demand enforcement of the Multiple Use Act and the National Environmental Policy Act. During this time, species listing under the Endangered Species Act became more active. Unfortunately, so many species are listed or are being considered for listing that it becomes impossible to develop biological information on causative factors for listing or recovery plans for each one. Peer-reviewed science that addresses management needs is often unavailable, and articles from the gray literature have been used in management plans for both threatened and endangered species and for public land. Personal biases of both scientists and land managers can influence the development of land management plans, especially in cases in which scientific information is minimal. The Land Grant System is well positioned to develop research applicable for public lands. Animal scientists need to be involved in interdisciplinary teams. Livestock producers need to overcome the stigma that livestock grazing is not a sustainable use. Rangeland in poor condition, whether public or private, should be improved if livestock managers are to change the public perception that grazing degrades rangeland. To accomplish this, education and peer pressure should be used. Another approach needed is activism on the part of producers and animal scientists. The public is demanding a voice in public land management. Working groups seem to be the emerging pathway to cooperatively develop management plans.  相似文献   
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