970 resultados para Copper Oxides--Microscopic Examination


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During the 24 hour period following inoculation, aggregation of spores and sporelings can have an important effect on the subsequent growth of filamentous fungi in submerged culture. This early phase of growth does not appear to have received much attention, and it was for this reason that the author's research was started. The aggregation, germination and early growth of the filamentous fungus Aspergillus niger have been followed in aerated tower fermenters, by microscopic examination. By studying many individual sporelings it has been possible to estimate the specific growth rate and germination times, and then to assess the branching characteristics of the fungus over a period of from 1 to 10 hours after germination. The results have been incorporated into computer models to simulate the development of the physical structure of individual and aggregated sporelings. Following germination, and an initial rapid growth phase, fungi were found to grow exponentially: in the case of A.niger the mean germination time was about 5 hours and the doubling time was as short as 1.5 hours. Branching also followed an exponential pattern and appeared to be related to hyphal length. Using a simple hypothesis for growth along with empirical parameters, typical fungal structures were generated using the computer models : these compared well with actual sporelings observed under the microscope. Preliminary work suggested that the techniques used in this research could be successfully applied to a range of filamentous fungi.

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This thesis is primarily concerned with the synthesis and polymerization of 5-methyl-1;3, 2-dioxathiolan-4-one-2-oxide (lactic acid anhydrosulphite (LAAS)) using anionic initiators under various conditions. Poly(lactic acid) is a biodegradable polymer which finds many uses in biomedical applications such as drug-delivery and wound-support systems. For such applications it is desirable to produce polymers having predictable molecular weight distributions and crystallinity, The use of anionic initiators offers a potential route to the creation of living polymers. The synthesis of LAAS was achieved by means of an established route though the procedure was modified to some extent and a new method of purification of the monomer using copper oxides was introduced, Chromatographic purification methods were also examined but found to be ineffective. An unusual impurity was discovered in some syntheses and this was identified by means of 1H and 13C NMR, elemental analysis and GC-MS. Since poly-α-esters having hydroxyl-bearing substituents might be expected to have high equilibrium water contents and hence low surface tension characteristics which might aid bio-compatibility, synthesis of gluconic acid anhydrosulphite was also attempted and the product characterised by 1H and 13C NMR. The kinetics of the decomposition of lactic acid anhydrosulphite by lithium tert-butoxide in nitrobenzene has been examined by means of gas evolution measurements. The kinetics of the reaction with potassium tert-butoxide (and also sec-butyl lithium) in tetrahydrofuran has been studied using calorimetric techniques. LAAS was block co-polymerized with styrene and also with 1,3-butadiene in tetrahydrofuran (in the latter case a statistical co-polymer was also produced).

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Polymer modified cements and mortars have become popular for use as patch repair materials. General evidence suggests that these materials offer considerable improvements compared to traditional mortars although the mechanisms for this are not fully understood. This work elucidates the factors which govern some properties and performance of different polymer systems. In view of the wide range of commercial systems available, investigations concentrated on the use of three of the most commonly available groups of polymers. These were: (1) Styrene Butadiene Rubber (SBR), (2) Acrylics and, (3) Ethylene Vinyl Acetates (EVA). The later two were in the form of both emulsions and redispersible powders. Experiments concentrated on: (1) Rheological behaviour of polymer modified cement pastes; (2) Workability of polymer modified mortars; (3) Influence of curing conditions on the pore size distribution and diffusion of chloride ions; (4) Bond strength of polymer modified cement and mortar patches; and (5) Microscopic examination and semi-quantitative analyses of the bulk and interfacial microstructures. The following main conclusions were reached: (1) The addition of polymer emulsions have a considerable influence on the workability of fresh cement pastes, the extent of this depending on the type of system used. (2) The rheological parameters of fresh polymer modified mortars can be established using a two-point workability test which may be used when comparing the properties of different systems at constant workability. (3) Curing conditions affect the properties of polymer modified systems and a wet/dry curing regime was essential for good adhesion of these materials to mortar substrates. (4) In contrast, the wet/dry curing regime resulted in a curing affected zone at the surface of patch materials. This can result in a much coarser pore structure and enhanced diffusion of e.g. chloride ions. (5) The microstructure of polymer modified systems was very different compared with the unmodified cement/mortar and varied depending on curing conditions.

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Variations in trace element abundances with depth in soils and sediments may be due to natural processes or reflect anthropogenic influences. The depth related variations of five major elements (Fe, Si, Al, Ca and Mg), seventeen trace elements (Mn, Cr, Ti, P, Ni, Ba, Sc, Sr, Sb, Zn, Pb, Cd, Co, V, Be, Cu and Y) and volatile loss patterns were examined for sediment cores from five sites in South Florida (Lake Okeechobee, SFWMD Water Conservation area 3B, F.I.U., the Everglades and Chekika State Recreation Area). Principal component analysis of the chemical data combined with microscopic examination of the soils reveal that depth-related variations can be explained by varying proportions of three natural soil constituents and one anthropogenic component. The results can be used as a geochemical baseline for human influence on South Florida soils.

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Objectives: Haematidrosis, also known as haematohidrosis, is a very rare condition where blood is excreted with sweat. As only a few cases have been described in the literature, we present guidelines on management of this rare phenomenon. Case: A 44-year-old man presented with self-limited and spontaneous bleeding episodes from different parts of his body. This had started 2 weeks before admission after an episode of extreme emotional stress. Medical history and laboratory tests were normal. The microscopic examination of a sample of the fluid excreted confirmed all blood elements. Conclusion: The disorder is thought to be related to activation of the sympathetic nervous system. The use of benzodiazepines and beta blockers may be helpful in controlling the bleeding episodes and give some comfort to the patient.

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BACKGROUND: Sialadenoma papilliferum (SP) is a rare, benign neoplasm of salivary gland origin which manifests as an exophytic papillary excrescence of the mucosa. Indeed, SP is both an exophytic proliferation of papillary stratified squamous epithelium above the mucosal surface and an endophytic salivary ductal proliferation beneath the mucosa. It arises predominantly in minor salivary glands and usually affects patients in the age range of 32-87 years, with reports in young patients being exceedingly rare.

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American visceral leishmaniasis is a zoonosis caused by Leishmania infantum and transmitted by the bite of the sand flies Lutzomia longipalpis.The main domestic reservoir is the dog, while foxes and opposums are the known wild reservoirs. However, identification of natural infections with L. infantum in rodents appears for need of investigating the participation of these rodents how source of infection of the parasite. In the present work the Leishmania infantum infection was investigated in rodents captured in Rio Grande do Norte, aiming at to offer subsidies to the understanding of the epidemic chains of LVA in the State. Thirteen Galea spixii were distributed in four groups, being G1 the group control with four animals and the others, G2, G3 and G4, with three animals each. Those animals were intraperitoneally inoculated with 107 promastigotas of L. infantum and accompanied for, respectively, 30, 90 and 180 days. Weekly the animals were monitored as for the corporal weight and rectal temperature. At the end of each stipulated period the animals were killed. Blood were used for determination of the parameters biochemical and haematological, PCR, ELISA, microscopic examination and cultivation in NNN medium. Liver, spleen and lymph node were used in Giemsa-stained impression and cultivation in NNN medium. Liver and spleen fragments were still used in PCR and histopathological, respectively. At the same time 79 rodents of the species Rattus rattus, Bolomys lasiurus, Oligoryzomys nigripis, Oryzomys subflavus and Trichomys apereoides were captured in the Municipal districts of Brejinho, Campo Grande, Coronel Ezequiel, Passa e Fica and Vázea for identification of natural infection with L. infantum. Evidence of infection was checked by direct examination of Giemsa-stained impression of liver, spleen and blood and culture of these tissues in NNN medium. Antibodies were researched by ELISA. They were not found differences among the weigh corporal final, rectal temperature and biochemical and haematological parameters of the Galea spixii controls and infected. The rectal temperature of the animals varied from 36OC to 40OC. For the first time values of the haematocrit (33,6% to 42,8%), hemoglobin (10,2 to 14,5g/dl), erythrocyts number (4,67x106 to 6,90x106/mm3), total leukocytes (0,9x103 to 9,2x103/mm3), platelets (49x103 to 509x103/mm3) total proteins (1,56 to 6,06 g/dl), albumin (1,34 to 3,05 g/dl) and globulins (0,20 to 3,01 g/dl) of the Galea spixii were determined. The lymphocytes were the most abundant leucocytes. Infection for L. infantum was diagnosed in two animals euthanasied 180 days after the infection. In one of the animals was also identified antibodies anti-Leishmania. The parasite was not found in none of the five other species of rodents captured. Galea spixii are resistant to the infection for L. infantum and they are not good models for the study for visceral leishmaniose, although they can act as infection sources. More studies are necessary to determine the paper of the rodents in the epidemic chain of transmission of the visceral leishmaniose in the State of Rio Grande do Norte

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Background: Rabies causes 55, 000 annual human deaths globally and about 10,000 people are exposed annually in Nigeria. Diagnosis of animal rabies in most African countries has been by direct microscopic examination. In Nigeria, the Seller’s stain test (SST) was employed until 2009. Before then, both SST and dFAT were used concurrently until the dFAT became the only standard method. Objective: This study was designed to assess the sensitivity and specificity of the SST in relation to the ‘gold standard’ dFAT in diagnosis of rabies in Nigeria. Methods: A total of 88 animal specimens submitted to the Rabies National Reference Laboratory, Nigeria were routinely tested for rabies by SST and dFAT. Results: Overall, 65.9% of the specimens were positive for rabies by SST, while 81.8% were positive by dFAT. The sensitivity of SST in relation to the gold standard dFAT was 81.0% (95% CIs; 69.7% - 88.6%), while the specificity was 100% (95% CIs; 76% - 100%). Conclusion: The relatively low sensitivity of the SST observed in this study calls for its replacement with the dFAT for accurate diagnosis of rabies and timely decisions on administration of PEP to prevent untimely deaths of exposed humans.

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Antecedentes: Las infecciones de vías urinarias (IVU) constituyen un padecimiento común a nivel mundial afectando a millones de personas cada año. Representan la segunda causa de infección más frecuente, únicamente superada por las infecciones del tracto respiratorio. Objetivo: Determinar la infección de vías urinarias mediante exámen elemental y microscópico de orina en los habitantes de la comunidad de Romerillo Tambo-Cañar 2015. Metodología: Se realizó un estudio de tipo descriptivo, de corte transversal, en un universo finito de 238 habitantes de la comunidad de Romerillo del cantón Tambo, del cual se obtuvo una muestra de 150 personas. Los participantes firmaron un consentimiento/asentimiento informado y llenaron una encuesta. Se analizaron las muestras de orina mediante un exámen elemental y microscópico de orina en el laboratorio del Centro de Diagnóstico y de Investigaciones Biomédicas de la Facultad de Ciencias Médicas de la Universidad de Cuenca, aplicando normas de bioseguridad y control de calidad. Los datos obtenidos fueron analizados para la estadística descriptiva y gráfica en los programas SPSS v22 y Microsoft Excel. Resultados: De 150 muestras analizadas, 9,3% fueron positivas para IVU, de éstas el 100% corresponde a mujeres y el 85,7% pertenece al grupo de edades entre 19 y 45 años. El 78,6 % mantienen una vida sexual activa; el 28,6% retiene el deseo de orinar de 30 a 60 minutos; el 85,7% realiza su higiene íntima cada 2-4 días y el 78,6% usa ropa interior o pantalón apretados

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ANTECEDENTES: Las infecciones urinarias (ITU) son una de las principales causas de morbimortalidad en el país. Las enterobacterias son los principales uropatógenos que por vía ascendente colonizan el tracto urinario. (1) OBJETIVO: Fue identificar el agente etiológico y sensibilidad a antimicrobianos en muestras de orina de los habitantes con infección urinaria de la comunidad de Chuichún-Tambo-Cañar. Agosto-Enero 2015-2016. METODOLOGÍA: Se realizó un estudio descriptivo de corte transversal compuesto por 1037 habitantes, cuya muestra representativa fue de 281 personas. Se realizó urocultivo y antibiograma previa detección de ITU mediante el Examen Elemental y Microscópico de Orina (EMO). Los participantes con su firma/huella en el consentimiento informado aceptaron colaborar en el proyecto, llenaron una encuesta con datos de filiación y variables de estudio, luego entregaron la muestra de orina para su respectivo análisis. Para procesar y tabular la información obtenida, se utilizaron los programas SPSS v22 y Microsoft Excel 2010 para la estadística descriptiva y gráfica. RESULTADOS: De 281 habitantes el 16,0% presentó infección urinaria según el EMO, de los cuales el 66,7% resultó urocultivo positivo. De los pacientes con ITU el 64,4% son mujeres entre 15–64 años. Escherichia coli resultó ser el microorganismo más frecuente (63,3%), seguido de Proteus spp, (16,7%), Enterococo (10,0%), Klebsiella spp (6,7%) y Estafilococo aureus (3,3%). CONCLUSIÓN: Las ITU afectan principalmente a mujeres, relacionándose con infecciones recurrentes, actividad sexual y mala práctica de hábitos de higiene.

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Antecedentes: La infección del tracto urinario es una de las patologías más comunes y forma parte de las principales causas de consulta médica y hospitalización. (1, 2) Es frecuente en mujeres, personas con vida sexual activa, mujeres embarazadas y diabéticos. El 10 al 20 % de mujeres entre los 18 y 40 años experimentan infección del tracto urinario, en hombres mayores a 50 años se asocia a problemas por hiperplasia prostática y en personas de la tercera edad la frecuencia es similar tanto en hombres como en mujeres. (1) Objetivo: Identificar infección de vías urinarias mediante el examen elemental y microscópico de orina en los habitantes de la comuna Sunicorral Tambo- Cañar 2015. Metodología: Estudio de tipo descriptivo transversal en habitantes la comuna Sunicorral, la muestra fue de 202 personas. Luego firmar del consentimiento y asentimiento informado, se llenó las encuesta con información relacionada a las variables de estudio, se recolectaron las muestras de orina y el análisis se realizó en el laboratorio del Centro de Diagnóstico de la Universidad de Cuenca, los datos obtenidos fueron analizado en el programa SPSS y Microsoft Excel y presentados en tablas y gráficos estadísticos. Resultados: De 202 muestras el 15% reportó infección del tracto urinario, el 87,1% fue mujer, el 25,8% correspondió a la edad de 10 a 19 años, el 64,6% realizó su higiene intima pasando uno o más días, el 62,0% tiene actividad sexual siendo un factor importante.

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ANTECEDENTES.- Las infecciones urinarias representan un grave problema de salud que afecta a la población en general. En El Tambo representan una de las principales causas de consulta externa y hospitalización. OBJETIVO.- Identificar la prevalencia de infecciones de vías urinarias, agente etiológico, sensibilidad a los antimicrobianos y factores asociados en los habitantes de la comunidad de San Francisco de Cuchocorral, El Tambo 2015. METODOLOGÍA.- El estudio fue descriptivo de corte transversal. El universo fue de 208 habitantes y la muestra de 160 personas de la comunidad. Se realizó el examen elemental y microscópico de orina, el urocultivo y el antibiograma. Previo a la recolección de las muestras, los participantes firmaron el consentimiento o asentimiento informado y llenaron una encuesta. Se analizaron las muestras en el laboratorio de Microbiología de la Facultad de Ciencias Médicas. Para relacionar los resultados obtenidos y las variables de estudio se utilizó el programa SPSS V22 y Excel para la estadística descriptiva. RESULTADOS.- La prevalencia de infección urinaria fue del 10%, siendo el 100% de personas con infección del sexo femenino y de ellas el 44% mujeres de 19 – 45 años. Escherichia coli fue el microorganismo más frecuente con el 87,5% y mostró resistencia para Trimetoprim sulfametoxazol y Gentamicina en un 28,6%. Proteus y Klebsiella presentaron resistencia para Ampicilina sulbactam y Fosfomicina en un 100%. CONCLUSIÓN.- Contribuimos con datos epidemiológicos sobre prevalencia de infecciones de vías urinarias, agente etiológico y sensibilidad a los antimicrobianos en los habitantes de la comunidad de San Francisco de Cuchocorral

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Antecedentes: La infección de vías urinarias corresponde a la invasión de microorganismos a los tejidos que conforman el tracto urinario, a cualquier nivel, la sintomatología depende del sitio y localización de la infección (1). Las mujeres debido a que su uretra es más corta que en los hombres tienen mayor probabilidad de contraer una Infección de vías urinarias (IVU) (2). Objetivo: Identificar la infección de vías urinarias, mediante el examen elemental y microscópico de orina, en los habitantes de la comunidad de Caguanapamba Tambo Cañar. Metodología: El estudio fue de tipo descriptivo de corte transversal, se realizó en la comunidad de Caguanapamba perteneciente al Cantón El Tambo, el universo lo constituyeron los 361 habitantes de la comunidad, según el documento de planificación territorial del cantón, la muestra estuvo representada por 186 personas quienes firmaron el consentimiento informado en donde se informó todo el proceso a seguir en la investigación, luego se aplicó una encuesta, que recopiló información relacionada con los datos de filiación y las variables consideradas de estudio. Las muestras fueron recolectadas bajo normas de calidad y bioseguridad a fin de garantizar los resultados. El procesamiento de las mismas se realizó en el Laboratorio del Centro de Diagnóstico de la Universidad de Cuenca. Para el análisis de resultados se utilizó los programas SPSS V22 Y Microsoft Excel, para la estadística descriptiva se utilizaron tablas y gráficos

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A study was conducted to influence of the diazinon pollutions effect to histopathologic change examination of ovarium and cortex adrenal glands the rat (Rattus norvegicus) caused of steroid inhibition metabolism. The treatment consisted of four level doses of diazinon as follows 0, 50, 100 and 200 ppm for 40 days, in drinking water. The microscopic examination result showed that vacuolar degeneration change in surrounding corpus atreticum and hemorrhagic lesion on interstitial cell of ovarian, in starting dose 50 ppm and then, the swollen cells and congestive lesion of cortex adrenal glands, in starting dose 100 ppm. (Animal Production 4(2): 101-111 (2002) Key words : Diazinon, Steroid, Cortex Adrenal Glands