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1.
Tissue and organ transplantation is a very complex interdisciplinary treatment, particularly in regard to unpaired organs, and it carries numerous risks for all participants in such an action. For the purpose of minimizing the risks to the allowed level and the preservation the humanitarian goals in medicine when performing the transplantation, professional and scientific doctrines and the respect of ethical and legal principles should be strictly observed. The paper presents the basic approaches in the estimation of justification, usefulness and certain forms of responsibility in the process of transplantation. Ethical and legal postulates which support transplantation to prevent deviation, deprivation or delinquency have also been reviewed.  相似文献   
2.
Summary Methacrylic acid was photopolymerised using CdS and composite, CdS/HgS and CdS/TiO2, colloidal semiconductor particles as initiators. The previously proposed photoinitiation mechanism involving the photogenerated positive hole in the valence band of the CdS colloid was confirmed by the electron scavenging action of TiO2. The effect of pH on the course of the polymerisation was investigated and is discussed.  相似文献   
3.
To clarify the histogenesis and differentiation potential of central neurocytoma, a pathological investigation of seven tumors from three patients was conducted using immunohistochemistry and ultrastructural analysis in addition to systematic in vitro studies. Six tumors were studied immunohistochemically and five were examined ultrastructurally. All cases that were immunostained were positive for synaptophysin in nuclear-free neuropil islands. In five tumors, a few tumor cells, in addition to reactive astrocytes, were positive for glial fibrillary acidic protein (GFAP). Vimentin staining was also positive in a few tumor cells of five specimens. Neurofilament staining was always negative. All cases for which ultrastructure was examined showed various synaptic abnormalities. Cultured cells were subdivided into three distinct tumor cell types: neuronal cells which stained for neurofilament proteins with neurosecretory granules; small flat undifferentiated cells with a high nuclear-cytoplasmic ratio and scant cytoplasmic organelles; and small round or multipolar astrocytic cells with 10-nm intermediate filaments which stained for GFAP. Our tissue culture studies disclosed that cultured neurocytoma cells form a cellular mosaic similar to subependymal plate layers that are composed of mitotically active cells, neurons and glia.  相似文献   
4.
Efficiency of organisation of management of the injured and diseased in combat operations in 1991/2 and results of hospital treatment are studied. The questionnaire was established for collection of data about stationary treatment of the wounded and diseased in 7 military and 15 civilian medical institutions. Data about 9.243 injured of whom only 5.57% were civilians are especially analysed. In most cases injuries were inflicted by mine-explosive devices (48.77% in combat and 6.27% in non-combat operations), then those inflicted by bullets (38.58% in combat and 8.02% in non-combat operations). Self-inflicted injuries occurred in 5.79% in combat and 10.32% in non-combat operations. Injuries inflicted in non-combat operations were found in a high percentage (46.60). They mostly occurred in the open air (41.26%). Injuries of extremities are predominant (64.70%), then injuries of the head and neck (17.90%), thorax (9.90%), abdomen and pelvis (7.50%). Young men (20-24 years old) were commonly injured but the older ones (over 40 years) have been also frequently injured (18.30%). Evacuation of the wounded and diseased was performed mainly by ambulances (about 60%) or helicopters (16%), especially to the medical institutions far in the country (to M.M.A. up to 60%). The first aid was given within the first ten minutes after injury in 55.00% and within 30 minutes in 65.58% of cases. Mutual aid was most frequently applied (33.12%) and then first aid given by general practitioners (32.12%). Surgical treatment was provided one hour after injury to every fourth wounded (24.08%) and after six hours to more than one third of the wounded (31.88%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
The formation of oxide phases in the system (1 -x) Fe2O3 +xGd2O3 was investigated for 0 x 1. On the basis of XRD measurements the distribution of oxide phases, -Fe2O3, Gd3Fe5O12, GdFeO3 and Gd2O3 was determined, as a function ofx. No solid solutions were observed with certainty even at the very ends of the concentration range. This was also confirmed by57Fe Mössbauer spectroscopy. New accurate crystallographic data for Gd3Fe5O12 are given. The formation of oxide phases in the system Fe2O3- Gd2O3 is compared with the data for analogous system Fe2O3-Eu2O3.  相似文献   
6.
International Journal on Software Tools for Technology Transfer - Randomized fault-tolerant distributed algorithms pose a number of challenges for automated verification: (i) parameterization in...  相似文献   
7.
Chemical and structural properties of the system (1–x)Fe2O3 + xNd2O3, 0x1, were investigated using X-ray diffraction, 57Fe Mössbauer spectroscopy and Fourier transform-infrared (FT-IR) spectroscopy. The samples were prepared by the chemical coprecipitation and thermal treatment of Fe(OH)3/Nd(OH)3 coprecipitates. X-ray diffraction showed the presence of oxide phases -Fe2O3 + NdFeO3 in the Fe2O3-rich region, and the oxide phases Nd2O3 + NdFeO3 in the Nd2O3-rich region. 57Fe Mössbauer spectra were characterized with one sextet of spectral lines at room temperature. Mathematical evaluation of the Mössbauer spectra showed distinct regularities in the changes of Mössbauer parameters, thus indicating the presence of two subspectra with very similar spectral behaviour. High sensitivity of the Nd2O3 phase to the moisture and atmosphere CO2 was demonstrated by FT-IR spectroscopy.  相似文献   
8.
The structural properties of the solid phase, formed by the hydrolysis of Fe3+ ions in Fe2(SO4)3 solutions at 90 or 120 °C, were investigated using X-ray diffraction,57Fe Mössbauer spectroscopy, Fourier transform-infrared spectroscopy (FT—IR) and transmission electron microscopy. The concentration regions of Fe2(SO4)3 were determined for the precipitation of goethite, -FeOOH, or hydronium jarosite, H3OFe3(OH)6(SO4)2 as a single phase. Superparamagnetic behaviour of -FeOOH particles was observed. Hydrolysis of Fe3+ ions in 0.1 M Fe2(SO4)3 solutions at 120 °C produced H3OFe3(OH)6(SO4)2 and basic sulphate, Fe4(OH)10SO4. The interpretation of57Fe Mössbauer and FT—IR spectra is given.  相似文献   
9.
Mixed metal oxides in the system Fe2O3-NiO were prepared by coprecipitation of Fe(OH)3/Ni(OH)2 and the thermal treatment of hydroxide coprecipitates up to 800 or 1100°C. X-ray diffraction showed the presence of -Fe2O3, NiO and NiFe2O4 in samples prepared at 800°C. The oxide phases -Fe2O3, NiO, NiFe2O4 and a phase with structure similar to NiFe2O4 were found in samples prepared at 1100°C. Fourier transform-infrared spectra of oxide phases formed in the system Fe2O3-NiO are discussed. Two very strong infrared bands at 553 and 475 cm–1, a weak intensity infrared band at 383 cm–1 and two shoulders at 626 and 441 cm–1 were observed for -Fe2O3 prepared at 1100°C. NiFe2O4, prepared at the same temperature, showed two broad and very strong infrared bands at 602 and 411 cm–1, while NiO showed a broad infrared band at 466 cm–1. Fourier transform infrared spectroscopic results were in agreement with X-ray diffraction.  相似文献   
10.
The paper presents a novel split-and-merge algorithm for hierarchical clustering of Gaussian mixture models, which tends to improve on the local optimal solution determined by the initial constellation. It is initialized by local optimal parameters obtained by using a baseline approach similar to k-means, and it tends to approach more closely to the global optimum of the target clustering function, by iteratively splitting and merging the clusters of Gaussian components obtained as the output of the baseline algorithm. The algorithm is further improved by introducing model selection in order to obtain the best possible trade-off between recognition accuracy and computational load in a Gaussian selection task applied within an actual recognition system. The proposed method is tested both on artificial data and in the framework of Gaussian selection performed within a real continuous speech recognition system, and in both cases an improvement over the baseline method has been observed.  相似文献   
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