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1.
Med Biol Eng Comput ; 58(5): 903-919, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32072432

RESUMO

Computed tomography angiography (CTA) is one of the most common vascular imaging modalities. However, for clinical use, it still requires laborious manual analysis. This study demonstrates the feasibility of a fully automated technology for the accurate detection and identification of several anatomical reference points (landmarks), commonly used in intravascular imaging. This technology uses two different approaches, specially designed for the detection of aortic root and supra-aortic and visceral branches. In order to adjust the parameters of the developed algorithms, a total of 33 computed tomography scans with different types of pathologies were selected. Furthermore, a total of 30 independently selected computed tomography scans were used to assess their performance. Accuracy was evaluated by comparing the locations of reference points manually marked by human experts with those that were automatically detected. For supra-aortic and visceral branches detection, average values of 91.8 % for recall and 98.8 % for precision were obtained. For aortic root detection, the average difference between the positions marked by the experts and those detected by the computer was 5.7 ± 7.3 mm. Finally, diameters and lengths of the aorta were measured at different locations related to the extracted landmarks. Those measurements agreed with the values reported by the literature. Graphical abstract Schematic description of the proposed algorithm. The input includes an already segmented aorta (left), there are two main sub-processes related to the detection of branches and roots (center), and the output includes the segmented original aorta with the branches and the detected landmarks superimposed (right).


Assuntos
Aorta/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Processamento de Imagem Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
Int J Comput Assist Radiol Surg ; 14(2): 345-355, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30244307

RESUMO

PURPOSE: The shape and size of the aortic lumen can be associated with several aortic diseases. Automated computer segmentation can provide a mechanism for extracting the main features of the aorta that may be used as a diagnostic aid for physicians. This article presents a new fully automated algorithm to extract the aorta geometry for either normal (with and without contrast) or abnormal computed tomography (CT) cases. METHODS: The algorithm we propose is a fast incremental technique that computes the 3D geometry of the aortic lumen from an initial contour located inside it. Our approach is based on the optimization of the 3D orientation of the cross sections of the aorta. The method uses a robust ellipse estimation algorithm and an energy-based optimization technique to automatically track the centerline and the cross sections. The optimization involves the size and eccentricity of the ellipse which best fits the aorta contour on each cross-sectional plane. The method works directly on the original CT and does not require a prior segmentation of the aortic lumen. We present experimental results to show the accuracy of the method and its ability to cope with challenging CT cases where the aortic lumen may have low contrast, different kinds of pathologies, artifacts, and even significant angulations due to severe elongations. RESULTS: The algorithm correctly tracked the aorta geometry in 380 of 385 CT cases. The mean of the dice similarity coefficient was 0.951 for aorta cross sections that were randomly selected from the whole database. The mean distance to a manually delineated segmentation of the aortic lumen was 0.9 mm for sixteen selected cases. CONCLUSIONS: The results achieved after the evaluation demonstrate that the proposed algorithm is robust and accurate for the automatic extraction of the aorta geometry for both normal (with and without contrast) and abnormal CT volumes.


Assuntos
Aorta/diagnóstico por imagem , Imageamento Tridimensional/métodos , Reconhecimento Automatizado de Padrão/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Artefatos , Humanos , Reprodutibilidade dos Testes
3.
Iran J Parasitol ; 12(4): 563-571, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29317881

RESUMO

BACKGROUND: This work studied the natural infection of Neospora caninum during the first gestation of heifers in a dairy farm in animals consuming a ration co ntaminated naturally with Zearalenone (ZEA), and to find out effect of mycotoxin in the levels of estrogen (E) and progesterone (P4) and that's relation to the infection to N. caninum and in the abortions. METHODS: The study was conducted in a dairy farm located in El Llano municipality, in Aguascalientes, Mexico, in 2013. Two groups were formed, the group "A" with 20 seronegative animals to N. caninum, and group "B" with 20 seropositive. Once a month was determined the levels of total IgG to N. caninum, the serum concentration of E and P4, and the level of ZEA in the ration; in cases of abortion, fetal brain samples were taken to identify the presence of N. caninum DNA. RESULTS: In group "A", was observed two subgroups: seronegative (60%) and seroconverted (40%), and three abortions. In group "B", all animals maintain their serostatus, and three animals aborted. All abortions were positive for N. caninum DNA. The level of ZEA in the ration has an average of 426 µg/kg; during the gestation did not identify that animals suffer any alteration in the levels of E or P4. No statistical differences among the studied variables (levels of E and P) in time (nine months of gestation) were detected. It was not identified any interaction with the natural exposure to ZEA intake in any of the groups under study. CONCLUSION: The chronic ingestion of ZEA does not affect serum concentrations of E and P4 during gestation of heifers under study and cannot be related to the infection for N. caninum and the abortion.

4.
Vet Parasitol ; 229: 50-53, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27809978

RESUMO

Reproductive alterations in hosts infected by parasites have been recognized in several phyla, especially in arthropods and mollusks, but it has been less studied in higher vertebrates, particularly in mammals. In the present study, ten eight week-old female New Zealand rabbits (Oryctolagus cuniculus) were either infected with Taenia pisiformis eggs or uninfected, and 7 weeks later they were mated. We found that serum progesterone levels were increased during pregnancy in infected does. At birth, litter size of infected does was reduced by half as compared to the control group, and, at weaning, the number of kits and the weight of litters was lower. Since serum progesterone levels have a key role in the maintenance of pregnancy and implantation, we propose that the observed prolificacy alterations in does infected with T. pisiformis infection were due to changes in the levels of circulating progesterone during pregnancy.


Assuntos
Cisticercose/veterinária , Progesterona/sangue , Coelhos , Taenia/isolamento & purificação , Animais , Estudos de Casos e Controles , Cisticercose/patologia , Feminino , Tamanho da Ninhada de Vivíparos , Gravidez
5.
Sensors (Basel) ; 16(3): 417, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-27011192

RESUMO

Seaport monitoring and management is a significant research area, in which infrastructure automatically collects big data sets that lead the organization in its multiple activities. Thus, this problem is heavily related to the fields of data acquisition, transfer, storage, big data analysis and information visualization. Las Palmas de Gran Canaria port is a good example of how a seaport generates big data volumes through a network of sensors. They are placed on meteorological stations and maritime buoys, registering environmental parameters. Likewise, the Automatic Identification System (AIS) registers several dynamic parameters about the tracked vessels. However, such an amount of data is useless without a system that enables a meaningful visualization and helps make decisions. In this work, we present SmartPort, a platform that offers a distributed architecture for the collection of the port sensors' data and a rich Internet application that allows the user to explore the geolocated data. The presented SmartPort tool is a representative, promising and inspiring approach to manage and develop a smart system. It covers a demanding need for big data analysis and visualization utilities for managing complex infrastructures, such as a seaport.

6.
Int. j. morphol ; 31(3): 888-893, set. 2013. ilus
Artigo em Espanhol | LILACS | ID: lil-694972

RESUMO

La citología vaginal puede usarse para caracterizar estados del ciclo reproductivo de la hembra. Sin embargo, no ha sido validada en ovinos de pelo, y ofrece resultados inexactos debido a interpretaciones subjetivas. El objetivo del presente trabajo es tipificar las características morfológicas y morfométricas de las células epiteliales de la vagina durante el ciclo estral en ovinos de pelo. Cinco borregas Santa Cruz se sincronizaron con esponjas intravaginales. Desde el día del 1er celo posterior al retiro de la esponja y hasta el siguiente celo, se obtuvieron muestras diarias del epitelio vaginal de cada oveja, y se cuantificó el número de células parabasales, intermedias y superficiales, y se midió la longitud, perímetro y área de citoplasma y núcleo de cada una. Los resultados muestran que las células superficiales incrementan (P<0,05) durante el estro en comparación con el diestro. En contraste, el número de células parabasales e intermedias es mayor (P<0,05) durante el diestro que en el estro. Las células más grandes (36,11+/-0,38 µm) y núcleos más pequeños (8,46+/-0,12 µm) se encontraron durante el estro, independientemente del tipo de célula, mientras que citoplasmas más pequeños (26,72+/-0,11 µm) y núcleos más grandes (10,48+/-0,02 µm) se observaron durante el diestro. Se concluye que la morfología de las células epiteliales de la vagina de la oveja de pelo coincide con las variaciones encontradas en otras hembras, y que el tamaño de citoplasmas y núcleos presenta un patrón cíclico que puede utilizarse para determinar de manera objetiva la etapa del ciclo estral de la oveja.


Vaginal cytology can be used to characterize stages of the reproductive cycle of the female. However, it has not been validated in hair sheep, and generates inaccurate results due to subjective interpretations. Thus, the purpose of the present work is to typify morphologic and morphometric characteristics of the epithelial cells from the vagina during the estrous cycle of hair sheep. Five Saint Croix ewes were synchronized with intravaginal sponges. Day zero of the cycle was considered the day of first estrus after sponge withdrawal. From this day until next estrus, samples from the vaginal epithelium were obtained daily from each ewe. The number of basal, intermediate and superficial cells was quantified, and length, perimeter, and area from cytoplasm and nucleus were obtained. The results show that the number of superficial cells increase (P<0.05) during estrus and decrease during the rest of the cycle. In contrast, the number of basal and intermediate cells showed an inverse pattern. The largest cells (36.11+/-0.38 µm) and smallest nucleuses (8.46+/-0.12 µm) were present during estrus, regardless of the cell type, while the smallest cells (26.72+/-0.11 µm) and larger nucleuses (10.48+/-0.02 µm) were observed during diestrus. It was concluded that citology of the epithelial cells from the vagina of hair ewes is in accord with changes found in other female spices, and that cytoplasm and nucleus sizes display a cyclic pattern that might be used to objectively determine the specific estrous cycle phase of the ewes.


Assuntos
Animais , Feminino , Células Epiteliais/citologia , Ciclo Estral , Ovinos/anatomia & histologia , Vagina/citologia
7.
Stud Health Technol Inform ; 173: 233-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22356993

RESUMO

AMILab is a free software for image analysis, processing and visualization. It provides convenient visualization tools for 2D and 3D images and it is highly extensible through its own scripting language. We describe the main visualization features and the scripting language of AMILab. The software includes an automatic C++ wrapping system which permits fast development of new visualization tools and image processing algorithms.


Assuntos
Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador , Software , Humanos
8.
Vet. Méx ; 32(4): 297-299, oct.-dic. 2001. CD-ROM
Artigo em Espanhol | LILACS | ID: lil-306656

RESUMO

Con el propósito de evaluar el efecto del sistema de crianza (extensivo vs semi-intensivo) del macho cabrío, en el entrenamiento para colecta de semen mediante vagina artificial, se utilizaron ocho animales criollos, de dos años de edad, con experiencia sexual; cuatro habían sido criados bajo condiciones extensivas, y los restantes bajo un manejo semiintensivo. Todos recibieron ocho sesiones de entrenamiento, exponiéndoles en forma individual, dos veces por semana, ante una hembra en celo durante 20 minutos o menos, para el caso de que eyacularan antes de cubrir el periodo. El orden de exposición se modificó en cada día de entrenamiento, pero siempre alternando los machos de acuerdo con su tipo de crianza. Los cuatro machos criados bajo condiciones semiintensivas eyacularon en la vagina artificial desde la primera exposición, mientras que ninguno de los animales criados bajo condiciones extensivas lograron eyacular durante las ocho sesiones de entrenamiento a que se sometieron. Los resultados sugieren que aquellos animales criados bajo condiciones extensivas, pueden desarrollar altos niveles de miedo durante evaluaciones sexuales ante la presencia cercana del humano, disminuyendo su motivación sexual bajo tales condiciones.


Assuntos
Comportamento Sexual Animal , Inseminação Artificial/métodos , Preservação do Sêmen/veterinária , Cruzamento
9.
Vet. Méx ; 32(4): 301-303, oct.-dic. 2001. CD-ROM
Artigo em Espanhol | LILACS | ID: lil-306657

RESUMO

Con el propósito de cuantificar la frecuencia con que se presenta el lamido poscopulatorio del pene en machos cabríos, así como su efecto en la transmisión de infecciones genitales, se realizaron dos experimentos. En el primero, se observaron tres cópulas de 25 machos, para registrar el tiempo entre la eyaculación y el lamido del pene, al igual que su frecuencia. Veintidós (88 por ciento) animales mostraron lamido del pene. De éstos, 7 por ciento, 30 por ciento y 50 por ciento manifestaron ese comportamiento después de una, dos o tres de las cópulas observadas, respectivamente. El tiempo promedio entre la eyaculación y el lamido del pene fue de 106.1ñ15.5 seg. En el segundo experimento se utilizaron 11 machos y ocho hembras infectadas con S. aureus. En seis de los machos se impidió el lamido del pene, mientras el resto permaneció como testigo. Después de la cópula, todos los machos en el grupo testigo se lamieron el pene. El 50 por ciento de los animales tratados y 60 por ciento de los testigos adquirieron la infección. Se concluye que el lamido del pene no se presenta luego de cada cópula ni en todos los machos, y que esta conducta no tiene una función de protección contra S. aureus.


Assuntos
Animais , Pênis , Cabras , Infecções Sexualmente Transmissíveis , Copulação
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