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266«C@yL@qyiym-J©yrMaL»#2î2â),2@19 / MEDICAL SOIMQIS
Сравнение средних значений в выборках осуществляли с помощью непараметрического критерия Уилкоксона-Манна-Уитни. Различия считали достоверными при р<0,05.
Результаты. Уровень ИЛ-8 в сыворотке крови у пациентов до операции в группах I и II был более чем в 2 раза выше уровня ИЛ-8 в сыворотке крови у пациентов III группы (р<0,05). Далее происходит постепенное увеличение уровня ИЛ-8 в сыворотке крови в I и II группах, и на 7-е сутки уровень ИЛ-8 увеличивается более чем в 2 и 3,5 раза (р<0,05), в отличии от группы без послеоперационных осложнений в виде 01111.
Выводы. Определено статистически значимое различие уровня ИЛ-8 у пациентов в группах с острым повреждением почек и пациентов без осложнений в послеоперационном периоде. У пациентов без осложненного послеоперационного периода в виде острого повреждения почек наблюдались более низкие концентрации ИЛ-8, что может говорить о возможности использования данного цитокина
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как дополнительного биомаркера ОПП после АКШ.
Литература.
1. Табакьян Е. А, Партигулов С. А. Биомаркеры ишемии и острого повреждения почек после операций на сердце с искусственным кровообращением// Анестезиология, реаниматология, перфузиология. -2013. -No 4. - С. 30-33. [Tabakyan E. A., Par- tig-ulov S. A. Biomarkers of ischemia and acute kidney injury after cardiac surgery with artificial circulation // Anesthesiology, resuscitation, perfusion. -2013.-No.4-P.30-33].
2. Колесников С. В., Борисов А. С. Острое почечное повреждение: новые аспекты известной проблемы// Патология кровообращения и кардиохирургия. -2013. -No 4. - С. 69-73. [Kolesnikov S. V., Borisov A. S. Acute renal damage: new aspects of the problem // Pathology of blood circulation and car-diosurger y. -2013. -No 4. - P. 69-73].
3. O'Neal J. B., Shaw A. D. Acute kidney injury following cardiac surgery: current understanding and future directions// Critical Care.- 2016.- P.-187.
УДК: 621.385.833.28
Afanasyev S.S. Kychkina T. V. Savvinova L.N.
Northeastern Federal University
SCANNING ELECTRON MICROSCOPE (ADVANTAGES AND DISADVANTAGES)
Abstract
Scanning electron microscope (SEM) is an equipment that uses beems of electrons in order to receive highresolution, three-dimensional and thorough images. It gives detailed information about the surface of any solid sample by focusing incidental electrons on the sample. Modern scanning electron microscopes obtains detailed surface data by tracing a specimen in a raster pattern with an electron beam. Raster microscopes are used as a research tool in physics, electronics, biology, pharmaceuticals, medicine, materials science, etc. Their main function is to obtain an enlarged image of a test sample and / or sample images in various recorded signals. Comparison of images obtained in different signals, allow us to conclude about the morphology and surface composition.
Key words: Scanning electron microscope, three-dimensional and thorough images.
The first Scanning electron microscope was invented in 1937 by Manfred von Ardenne who introduced a high magnification microscope that could scan a quite small raster with demagnified and highly focused electron beams [1]. At first the electron gun creates a beam of energetic electrons onto a number of electromagnetic lenses. The lenses are tubes that are wrapped in coil and are called solenoids. These coils are able to focus the incident electron beams onto the specimen. These adjuctments can increase or decrease the speed in which the electrons contact with the surface of the sample. The beam can be adjucted by computer in order to control magnification volume and determine the surface of the zone that should be scanned. Most samples are prepared before they are placed in the vacuum chamber. The most often used preparations that are used proir SEM analysis are sputter coating that is used for non-conductive samples and the other is dehydration of biological specimens.
All samples should be durable to low pressure that occurs in the vacuum chamber. The acceleration rate of
incident electrons reflect the interaction between the incident electrons and the surface of the specimen. Those electrons carry kinetic energy before they are focused onto the sample. During the interaction of the incident electrons and the surface of the sample the surface of the sample releases energetic electrons that carry detailed information about the sample, such as information on its size, shape, composition and texture.
The image perceived by SEM is usually black and white and three-dimensional with magnification of about 10 nanometer [1]. SEM makes it possible to have high-resolution and detailed picture of the surface of the sample.
SEM has a number of applications in different fields of our life, such as in science, in industry, in medicine, biology, gemology, forensic science and so on. These are the spheres where characterizations of solid materials are required.
On the one hand, SEM can give topographical, morphological as well as compositional data. On the other hand, SEM can find and analyze surface rupture,
medical SCIENCES / «c®yL®qyiym-j®yrMaL»#2i26),2@i9
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can inform about the state of microstructures, can study the surface corruption, provide qualificative chemical analysis, define crystalline structures and so on.
SEM has a range of advantages. First of all, SEMs are quite easy to operate with prior training and knowledge in computer technologies. It works quite fast, and it may take about five minute to complete SEI, BSE and other analysis. The detailed three-dimensional and topographical imaging and versatile data makes SEM a wonderful tool for different studies. SEM can generate information in digital form that is very convenient. SEM is also convenient because it requires minimal preparation of samples before they are placed into the vacuum chamber. If the sample is not organic, only preparation of its surface is required and after that it is affixed to the mounting stub. The surfaces that is examined can be split, sliced, fractured or microtomed. On the other hand, if the sample is hygroscopic and needs structural change with moisture variation, it may need special drying techniques of varying levels of complexity. The degree of drying technique depends on the moisture sensitivity of the material.
Another aspect of SEM is that it also requires that nonconductive surfaces must be metalized. Primary beam electrons will create static charge in case they are not conducted to ground. Metal coating plays this role for nonconductive materials. The coating process requires evaporation of the metal onto the surface of the sampleat a vacuum.
In addition, one more advantage of SEM is the great sample size range that can be applied, the maximum of which is up to one cm3. Such surfaces can be quickly scanned in condition of low magnification zooming in on areas of particular interest without change of magnification. At the same time a detailed, three-dimensional image can be received from a very thin section.
In other words, SEM has a lot of advantages that include rapid sample reparation, ability of study of large surface areas, great depth of examination field, availability of a large range of magnifications requiting little or no focusing for large alterations, and many others.
SEM has also a number of disadvantages. One of the disadvantages of scanning electron microscope is its cost and size. SEMs are quite expensive and occupy much space. They should be placed in an area that is free of any electric, magnetic and vibration interference. It requires steady and unchanged voltage, circulation of cool water and currents to electromagnetic coils.
At the same time it is important to have special training both for operating a scanning electron microscope and for preparation of samples. The later can result in artifacts. Knowledge and experience of the researcher can minimize the negative impact though it is not possible to eliminate or identify all potential artifacts.
Scanning electron microscopes are also limited to solid and non-organic specimens that are not quite big for being placed into the vacuum pressure. All the samples must be durable to low pressure. Scanning electron
microscopes have little, but quite possible risk of radiation exposuredue to the electrons scatter from beneath the surface of the specimen. That's why SEM operators and researchers are recommended to take safety measures.
The use of the scanning electron microscope requires that the column should constantly be at a vacuum. This is required because if the sample is surrounded with gas, an electron beam will not be produced for the reason that of a high instability in the beam, and because gases could react with the electron source which causes the electrons in the beam to ionise and make accidental discharges. This may lead to instability in the beam.
Also the transmission of the beam throughout the electron optic column may also be slowed down by the existence of molecules that may have come from the specimen or the microscope itself that might form compounds and condense on the specimen. If this happens, it may lower the contrast and making the produced image unclear. [2]
All in all, SEM has plenty of advantages that make the SEM a very important and necessary tool in almost all spheres of research, and there are a couple of disadvantages which should not be ignored but which can be easily coped with.
Let's look through some fields where the SEM can be used. As I have mentioned above, the scanning electron microscope can be used in forensic science. SEM makes it possible to study elements that have very small sample quite fast. It makes it possible to determine the origin of materials that are important and necessary for case investigation, such as fingerprints, fragments of documents, counterfeit bank notes, gunshot remains and many others. Also it can create a thorough pictures of microorganisms, organic structures and gems that need to be examined.
Due to the scanning electron microscope researchers can obtain non-negative testing of natural and nonliving specimens. It can even examine and identify dust and particles in the air of indoor space and evaluate the quality of the air. Mineral grains such as glass, mica and carbonates, such biological materials like pathogen spores, insect particles, skin cells, textile fibers, carpet fibers, hair and cellulose can also be be investigated using the scanning electron microscope; this is why the SEM is one of the most useful equipment to use in fo-rensics.
In biological sciences, SEMs can be used on anything from insects and animal tissue to bacteria and viruses. Uses include: measuring the effect of climate change of species, identifying new bacteria and virulent strains, vaccination testin, discovering new species and work in the sphere of genetics.
Scanning electron microscopes are used in medical science to compare blood and tissue samples in determining the cause of illness and measuring the effects of treatments on patients. Common uses include identifying diseases and viruses, testing new vaccinations and medicines, comparing tissue samples between patients in a control and test group and finally testing samples over the lifespan of patients.
«C@yL@qyiym-J©yrMaL»#2î2â),2@19 / MEDICAL SCIENCES
As it was mentioned above, SEMs are also widely used in geology. Geological sampling using a scanning electron microscope can determine weathering processes and morphology of the samples. Electron imaging can be used to identify compositional differences, while composition of elements can be provided by mi-croanalysis. SEM provides identification of tools and early human artefacts, examination of soil quality for farming and agriculture, dating historic ruins and evidence of soil quality, toxins etc.
All in all, in this essay I have discussed the operation principles of scanning electron microscopes, its advantages and disadvantages and some fields where SEMs are applied successfully. I believe that SEMs are
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very practical and their help in different aspects of research is invaluable. List of literature
1. Bernard M. Collett. Scanning electron microscopy: a review and report of research in wood science. Forest Products Laboratory, University of California, Richmond 94804 p.
2. Om Prakash Choudhary* and Priyanka//Scanning Electron Microscope: Advantages and Disadvantages in Imaging Components. International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 6 Number 5 (2017) pp. 1877-1882
УДК 615.4:616-7:617:618-7
Газизов Рустем Аудитович
кандидат технических наук, доцент;
Ямалеева Екатерина Сергеевна кандидат технических наук, доцент;
Мусин Ильдар Наилевич
кандидат технических наук, заведующий кафедрой медицинской инженерии;
Хусаинова Гузель Рафаэлевна
кандидат технических наук, доцент Казанский национальный исследовательский технологический университет, г. Казань, РФ
НОРМАТИВНАЯ БАЗА ОБОРОТА МЕДИЦИНСКИХ ИЗДЕЛИЙ В ЕВРОПЕЙСКОМ
СОЮЗЕ
Gazizov Rustem Auditovich
Candidate of Technical Sciences, Associate Professor;
Yamaleeva Ekaterina Sergeevna Candidate of Technical Sciences, Associate Professor;
Musin Ildar Nailevich
Candidate of Technical Sciences, Head of the Department of Medical Engineering;
Husainova Guzel Rafaelevna
Candidate of Technical Sciences, Associate Professor Kazan National Research Technological University, Kazan, Russian Federation
NORMATIVE BASE OF MEDICAL PRODUCTS TRAFFICKING IN THE EUROPEAN UNION
Аннотация
В работе рассматриваются новые законодательные акты (Регламенты) в области подтверждения соответствия медицинских изделий в Евросоюзе, принятых взамен соответствующих Директив. Сделан акцент на наиболее важные и значимые новые требования к производству, контролю, сертификации и безопасности медицинских устройств. Описаны основные отличия новых правил от действующих в переходный период Директив о медицинских устройствах.
Abstract
In work new acts (Regulations) in the field of confirmation of compliance of the medical products in the European Union accepted in exchange the corresponding Directives are considered. The emphasis on the most important and the significant new requirements to production, control, certification and safety of medical devices is placed. The main differences of new rules from the Directives on medical devices existing during a transition period are described.
Ключевые слова: медицинские изделия, Европейский Союз, Регламент, Директива, безопасность.
Key words: medical products, European Union, Regulations, Directive, safety.
26 мая 2017 года на территории Европейского Союза вступили в силу Регламент ЕС о медицинских изделиях 2017/745 (Regulation (EU) 2017/745 of the European Parliament and of the Council of 5 April 2017 on medical devices) - MDR и Регламент ЕС о медицинских изделиях in vitro (Regulation
(EU) 2017/746 of the European Parliament and of the Council of 5 April 2017 on in vitro diagnostic medical devices and repealing) - IVDR. Они заменяют три существующих Директивы о медицинских устройствах: 90/385/EEC Active implantable medical devices - Активные медицинские имплантируемые
