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1.
Bartosz Paprota Roman Król Andrzej Wiatrak 《Chirurgia narzadów ruchu i ortopedia polska》2004,69(2):85-89
The authors present the results of hip arthroplasty of 67 patients treated after failed internal fixation of the osteoporotic, trochanteric fractures of the femur, which were primary stabilised with angular plate AO in 39 patients and with dynamic hip screw (DHS) in 28 patients. In the discussed material 16 persons were male and 51 female, in the age between 51 and 83 years old. According to the Evans classification in 4 cases we diagnosed type I of fracture, in 10--type II, 31--type III and in 22--type IV. Hip arthroplasty was made from the 3rd to the 39th week after primary fixation of the fracture. In 42 patients we made total hip arthroplasty, in 14 cases Austin-Moore hemiarthroplasty, and in 11 patients bipolar arthroplasty. According to the Postel and Merle d'Aubigne classification there were obtained 29 very good, 21 good and 17 satisfactory results. 相似文献
2.
Disturbances of cell-mediated immunity in ornithosis 总被引:1,自引:0,他引:1
L Konopka S Koba M Partyka K Ma?lanka W Kryczka B Szerszén B Bartosz 《Archivum immunologiae et therapiae experimentalis》1984,32(2):177-184
27 cases of ornithosis were observed during an epidemia in 1980 in Kielce and subsequently followed with respect to immunological characteristics of peripheral blood lymphocytes. Blastic transformation of these cells was tested after stimulation in vitro with three different mitogens. Identification of peripheral blood T and B lymphocytes was done using rosette tests (E,EA,EAC) and the occurrence of surface immunoglobulins was determined by the immunofluorescent method with polyvalent anti-immunoglobulin serum. The counts of T and B lymphocytes in the peripheral blood were normal throughout the whole period of the observation, but from the 3rd week on a significant impairment of 3H-thymidine incorporation into the cells stimulated with Con A was observed, and from the 10th week on, this impairment appeared also in cells stimulated with PHA and PWM. These observations revealed considerable disturbances in cell-mediated reactivity in patients with ornithosis and seem to be connected with chronic infection with Chlamydia psittaci. 相似文献
3.
Grzegorz Bartosz Miroslaw Soszynski Wanda Retelewska 《Mechanisms of ageing and development》1981,17(3):237-251
Superoxide dismutase (SOD) content estimated by rocket immunoelectrophoresis did not differ in various density (age) fractions of bovine erythrocytes though its specific activity decreased with increasing cell density. No changes were found, either, in the crossed immunoelectrophoretic pattern of SOD with increasing red cell age. Effects of different denaturing agents on the immunoelectrophoretic pattern and activity of the enzyme were compared, including H2O2 and free radicals generated by ionizing radiation. The yield for inactivation was higher than that for loss of antigenic properties in all cases studied which could correspond to the in vivo situation. However, changes in electro-phoretic mobility were revealed for all the denaturing agents, which is contrary to a main causative role of these agents in the in vivo inactivation of SOD. The results suggest spontaneous “subtle denaturation” as a chief cause for the SOD inactivation during erythrocyte aging. 相似文献
4.
Curcumin is one of the most frequently researched herbal substances; however, it has been reported to have a poor bioavailability and fast metabolism, which has led to doubts about its effectiveness. Curcumin has antioxidant and anti-inflammatory effects, and has demonstrated favorable health effects. Nevertheless, well-reported in vivo pharmacological activities of curcumin are limited by its poor solubility, bioavailability, and pharmacokinetic profile. The bidirectional interactions between curcumin and gut microbiota play key roles in understanding the ambiguity between the bioavailability and biological activity of curcumin, including its wider health impact. 相似文献
5.
Bartosz Zieliski Krzysztof Nadolny Wojciech Zawadka Tomasz Chaciski Wojciech Stachurski Gilmar Ferreira Batalha 《Materials》2022,15(21)
This work presents the results of an experimental study of the sharpening of planar technical blades used in the fish processing industry. Sharpening was carried out in the grinding process using several environmentally friendly methods of cooling and lubricating the machining zone (MQL method, CAG nozzle, hybrid method that is a combination of MQL and CAG methods, as well as WET flooding method as reference). The purpose of the research was to determine the possibility of reducing the negative environmental impact of the sharpening process of technical blades by minimizing the expenditure of coolant. The application of the MQL method and the hybrid MQL + CAG method provided a very good realization of the lubricating function so that the share of friction of dulled cutting vertices against the workpiece surface is reduced, which manifests itself in the reduction of the grinding force and the correlated grinding power. In the case of grinding under cooled compressed air delivery conditions, the average cutting force was as much as 91.6% higher (F = 22.63 N) compared to the result obtained for the most favorable flooding method, demonstrating the insufficient quality of the blade shaped under such conditions. A comprehensive comparison of test results on grinding power gain, cutting force and surface texture suggests that the most favorable sharpening results were obtained using the environmentally friendly MQL method of cooling and lubricating the grinding zone. 相似文献
6.
In this work, Ba2MgWO6: Eu3+ (BMW: Eu3+) ceramic materials with a double perovskite structure were sintered using the High-Pressure Low-Temperature sintering (HPLT) technique. As part of the research, the influence of pressure (CP), sintering temperature (CT), and sintering time (CTS) on the structure and luminescence of the doped BMW were determined. Structural analysis via XRD and SEM + EDS and spectroscopic analysis via emission and excitation spectra, decay time, and absorption spectra of the obtained ceramics were performed. Dense double perovskite ceramics were obtained with a cubic structure with optimal sintering parameters: T = 500 °C, p = 8 GPa, and t = 1 min. The increase in temperature caused an increased extinction of the luminescence due to the diffusion of carbon into the ceramics. The increase in pressure led to the formation of the amorphous phase, which increased the speed of non-radiative transitions and also led to the extinction of the luminescence. The increase in sintering time from 1 to 3 min enhanced the luminescence output, but when the ceramic was sintered for 5 min, the luminescence was quenched, most likely by increasing the rate of the non-radiative process, as evidenced by reduced decay time. 相似文献
7.
Bartosz Zieliski Krzysztof Nadolny Wojciech Zawadka Tomasz Chaciski Wojciech Stachurski Gilmar Ferreira Batalha 《Materials》2022,15(22)
The most widely used method for shaping technical blades is grinding with abrasive tools made of cubic boron nitride (cBN) grains and vitrified bond. The goal of this work was to determine the effect of grinding wheel grain size (cBN grain number according to FEPA standards: B126, B181 and B251), kinematics (grinding with the circumference, face and conical surface of the wheel) and feed rate (vf = 100; 150; 200 mm/min) on the effects of the grinding process evaluated by the cutting force of the blade after machining F, blade surface texture parameters (Sa, St, Smvr, Str, Sdq, Sdr and Sbi) as well as blade surface morphology. An analysis of output quantities showed that grinding wheels made of B181 cBN grains are most favorable for shaping planar technical blades of X39Cr13 steel in the grinding process. 相似文献
8.
Sylwia Wiewirowska Marek Siemiski Tomasz
leboda Aneta ukaszek-Soek Tomasz Dyl Bartosz Koczurkiewicz 《Materials》2022,15(24)
The research presented in this article aimed to obtain a semi-finished product in the form of TRIP wires, which in further research will be used to produce fasteners in the form of KPS-6 screws used in the construction industry. At present, the process of manufacturing this type of fastener (from wire rod to the finished product) involves two technological lines: one for carrying out the drawing process and obtaining a semi-finished product in the form of a wire with appropriate properties, and the other for the production of fasteners. Semi-finished product wires with a ferritic-perlitic structure obtained after the drawing process are the starting product for the production of fasteners, the tensile strength of which is approximately 450 MPa. In order to be able to obtain fasteners characterized by an increased level of properties in 8.8 grade, after the screw manufacturing process, heat treatment should be carried out by hardening and tempering. The new technology proposed in the article includes: a drawing wire rod with a semi-finished product diameter, two-stage heat treatment on the line for pass-through heating and cooling, ensuring the obtaining of a TRIP-type structure in drawn wires, and calibration drawing. The product of this process was a wire whose tensile strength was in the range of 700–800 MPa with a TRIP structure. Thanks to obtaining a TRIP-type structure with the assumed amount of retained austenite, we obtained wires with higher strength properties and very high plasticity in relation to wires with the same chemical composition and ferritic and perlitic structure. The research carried out in the article also allowed us to obtain, in the semi-finished product wires, a favourable relationship between the strength properties and plasticity of the material, expressed by the value of the Re/Rm coefficient (yield strength/tensile strength) and the so-called yield ratio, which determines the material′s susceptibility to cold deformation; the smaller these coefficients, the greater the yield strength. The subsequent stages of the research will include the development of forming fasteners in the form of KPS-6 screws used in the steel construction industry with TRIP structures, with increased properties of products in the 8.8 property class, without conducting heat treatment by hardening and tempering. It is assumed that the resulting product will have an additional usable feature: preserving a certain amount of retained austenite in the structure of the finished fasteners, which will be transformed into martensite during operation, and thus affect the longevity of the fasteners. 相似文献
9.
Rafa Zybaa Bartosz Bucholc Kamil Kaszyca Krystian Kowiorski Dominika Sobo Wojciech rawski Dorota Moszczyska Rafa Molak Zbigniew Pakiea 《Materials》2022,15(24)
Additive manufacturing (AM) has seen remarkable development in recent years due to relatively high efficiency of the process. Cold spraying (CS) is a particular method of AM, in which titanium and titanium alloy powders are used. CS is a very competitive technology enabling the deposition of coatings, repairing machine parts, and manufacturing new components. For specific applications, the surface of cold-sprayed materials may require further processing. This paper reports an attempt to employ laser surface treatment (LST) of cold-sprayed coatings on an aluminium alloy substrate. The influence of laser beam interaction time on the coatings’ properties was analysed. The microstructure was investigated and observed employing scanning electron microscopy (SEM). To evaluate residual stress after CS and LST, the sin2ψ technique was used. Investigations were also performed on Vickers hardness, contact angle, and surface roughness. Significant changes in the surface morphology of the coatings and elevated residual stress levels dependent on the laser beam interaction time were observed. Increased Vickers hardness was recorded for titanium alloy Ti6Al4V. LST also led to increased surface hydrophilicity of the modified materials Ti and Ti6Al4V. 相似文献
10.
Agnieszka Kij Anna Bar Izabela Czyzynska-Cichon Kamil Przyborowski Bartosz Proniewski Lukasz Mateuszuk Zuzanna Kurylowicz Agnieszka Jasztal Elzbieta Buczek Anna Kurpinska Joanna Suraj-Prazmowska Brygida Marczyk Karolina Matyjaszczyk-Gwarda Andreas Daiber Matthias Oelze Maria Walczak Stefan Chlopicki 《Acta physiologica (Oxford, England)》2024,240(4):e14116