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Estudio del seno coronario y sus tributarias en individuos colombianos Study of the coronary sinus and its tributaries in colombian subjects  [cached]
Luis E Ballesteros,Luis M Ramírez,Pedro L Forero
Revista Colombiana de Cardiología , 2010,
Abstract: La expresión morfológica del seno coronario se caracteriza por su gran variabilidad, especialmente en lo que se relaciona con longitud, calibres, territorios drenados y frecuencia de sus tributarias. Se evaluaron las variaciones del seno coronario en 68 senos coronarios (56 hombres; 12 mujeres) de corazones extraídos como material de necropsia, a individuos colombianos. Los senos fueron inyectados con resina sintética y se registraron sus características anatómicas. La longitud promedio de los senos fue de 25,96 mm (± 6,34) y su diámetro distal de 8,94 mm (± 1,66). Las formas fueron cilíndrica, en embudo y aplanada en 67,6%, 23,5% y 8,9% respectivamente. La vena cardiaca magna se originó en el ápex cardiaco en 57,4% de los casos y en el tercio inferior del surco interventricular anterior en 39,7%. A nivel del surco atrioventricular tuvo un calibre de 5,47 mm (± 0,72). En 77,9% la vena cardiaca magna se ubicó a la izquierda de la arteria interventricular anterior. El trígono arterio-venoso del corazón estuvo presente en 58,8%. La vena cardiaca media tuvo como origen el tercio inferior de la superficie ventricular anterior (53%) y el ápex cardiaco (47%). ésta desembocó directamente en el atrio derecho en 17% de los casos. Su calibre en el segmento cercano al seno fue de 4 mm (± 0,77). Se presentó anastomosis de las venas cardiacas magna y media en 58,8%; en el ápex cardiaco (33,8%) y en el segmento inferior del surco interventricular anterior. Se destaca la presencia de una vena cardiaca magna corta y de una vena cardiaca media de amplia trayectoria en un número significativo de casos. De igual forma, la desembocadura de la vena cardiaca media en el atrio derecho estuvo presente en casi una quinta parte de los corazones estudiados. The morphological expression of the coronary sinus is characterized by its great variability, especially with regard to length, caliber, drainage territories and frequency of its tributaries. We assessed the variants in the coronary sinus of 68 fresh hearts from Colombian subjects (56 men, 12 women), from autopsy material. The sinuses were injected with synthetic resin and its anatomic characteristics were recorded. The average length of the coronary sinuses was 25.96 mm (± 6.34) with a distal diameter of 8.94 mm (± 1.66). The shapes were cylindrical, funnel-shaped and flattened in 67.6%, 23.5% and 8.9% respectively. The great cardiac vein originated from the cardiac apex in 57.4% of cases and in the lower third of the anterior interventricular sulcus in 39.7%. At the atrioventricular groove level, it had a caliber of 5.47 mm (
Topografía y Biometría del Sistema Venoso Coronario y de sus tributarias
Sousa-Rodrigues,C. F.; Alcantara,F. S.; Olave,E;
International Journal of Morphology , 2005, DOI: 10.4067/S0717-95022005000200013
Abstract: the coronary sinus (sc) is the main end of the cardiac veins, being the principal vein of the heart, draining all its blood, except that driven by the anterior cardiac veins and the minimum cardiac veins. its location is well-defined in the posterior portion of the coronary sulcus between left atrium and ventricle. its direct tributaries are the cardiac veins: magna (vcm), media (vcme), parva (vcp), oblique of the left atrium (voae), posterior veins of the left ventricle (vpve). the diameter in the middle of the distal third of the coronary sinus ranged from 4 to 10 mm (mean 6,34 mm); about its medium third, such value ranged from 7 to 14 mm (mean 9,13 mm) and in its proximal third, its diameter ranged from 5 to 16 mm (mean 9,28 mm). its length ranged from 27 to 54 mm (mean 40,3 mm). in 26 hearts (100 % of the cases), the vcm continued into the sc in its left side; in 22 cases (84,6%), the voae flowed into its left third; in the remaining 4 (15,4%), it was absent; the sc received the left marginal vein in 3 hearts (11,5%). in 26 cases (100%), the vcme discharged in the right extremity of the sc; in 16 hearts (61,5%), some vpve drained into the left third of the sc, in these there was 1 vpve in 10 (38,5%), 2 vpve in 4 (15,3%) and 3 vpve in 2 (7,7%). in 23 hearts (88,5%), some vpve discharged in the middle third of the sc; in these, there was 1 vpve in 15 cases (57,7%) and 2 vpve in 8 (30,8%). in 21 hearts (80,8%), some vpve drained into the right third of the sc, in these, there was 1 vpve in 14 (53,9%), 2 vpve in 5 (19,2%), 3 vpve in 2 (7,7 %). one of the most polemic aspects in the study of the coronary sinus is its own biometry, contributing to this divergence the absence of a standart location to its beginning and a pattern on tributaries disposition
Estudio del seno coronario y sus tributarias en individuos colombianos
Ballesteros,Luis E; Ramírez,Luis M; Forero,Pedro L;
Revista Colombiana de Cardiología , 2010,
Abstract: the morphological expression of the coronary sinus is characterized by its great variability, especially with regard to length, caliber, drainage territories and frequency of its tributaries. we assessed the variants in the coronary sinus of 68 fresh hearts from colombian subjects (56 men, 12 women), from autopsy material. the sinuses were injected with synthetic resin and its anatomic characteristics were recorded. the average length of the coronary sinuses was 25.96 mm (± 6.34) with a distal diameter of 8.94 mm (± 1.66). the shapes were cylindrical, funnel-shaped and flattened in 67.6%, 23.5% and 8.9% respectively. the great cardiac vein originated from the cardiac apex in 57.4% of cases and in the lower third of the anterior interventricular sulcus in 39.7%. at the atrioventricular groove level, it had a caliber of 5.47 mm (± 0.72). in 77.9%, the great cardiac vein was located to the left of the anterior interventricular artery. the arterio-venous trigone of the heart was present in 58.8%. the middle cardiac vein had its origin in the lower third of the anterior ventricular surface (53%) and the cardiac apex (47%). this drained directly into the right atrium in 17% of cases. its caliber in the segment close to the sinus was 4 mm (± 0.77). anastomosis of the great and middle cardiac veins was present in 58.8%;33.8% in the heart apex and in the anterior interventricular sulcus. in a significant number of cases, the presence of a short great cardiac vein and an elongated middle cardiac vein was highlighted. similarly, the drainage of the middle cardiac vein into the right atrium was present in almost one fifth of the hearts studied.
Anatomía quirúrgica del drenaje venoso en la región del triángulo carotídeo Surgical anatomy of jugular vein tributaries
JOSé GONZáLEZ R,MARIO CANTíN L,CéSAR CORONADO G,IVáN SUAZO G
Revista Chilena de Cirugía , 2010,
Abstract: Los principales afl uentes de la vena yugular interna se incorporan a nivel cervical por medio del tronco venoso tirolinguofacial. Clásicamente se ha descrito su formación por la unión de la vena facial, lingual y tiroidea superior. El objetivo de este estudio fue determinar las variaciones en la presentación del tronco tirolinguofacial en cadáveres humanos de la región del Maule, Chile. Se disecaron 30 hemicuellos pertenecientes a 15 cadáveres humanos de ambos sexos, con un rango de edad entre 29 y 50 a os, y se analizaron mediante observación directa. Se observó la formación de tronco venoso en la totalidad de los casos, siendo 53,3% correspondiente al tronco de tipo tirolinguofacial, 23,3% linguofacial, 20% tirolingual y sólo un 3,3% el tronco tirolinguofaringofacial. No se encontró la formación del tronco venoso de tipo tirofacial. Además se encontró una correlación significativa entre el diámetro de la vena yugular interna y el tronco venoso conformado por estas venas. Por lo tanto, existen variaciones morfológicas en los patrones de conformación de las venas facial, lingual y tiroidea superior, siendo estos datos de importancia para áreas de cirugía oncológica, cirugía plástica, cirugía de cabeza y cuello y radiología. Background: The main tributaries of the internal jugular vein join at cervical level through the venous thyrolinguofacial trunk. This trunk is classically described as formed by the union of the facial, superior thyroid and lingual veins. Aim: To evaluate variations in the formation of the thyrolinguofacial trunk in human cadavers. Material and Methods: Thirty hemi-necks were dissected in human cadavers of nine men and six women, with ages ranging between 29 and 50 years, and analyzed by direct observation. Results: In 16 hemi-necks (53.3%), the trunk was thyrolinguofacial; in seven (23.3%), it was linguofacial; in six (20%), it was thyrolingual and in one case (3.3%) it was thyrolinguo pharyngofacial. No thyrofacial trunk formation was found. There was a correlation between the diameter of the internal jugular vein and of the venous trunk formed by these veins. Conclusions: There are morphological changes in the formation patterns of facial, lingual and superior thyroid veins. This information is useful for surgical oncology, plastic surgery, head and neck surgery and radiology.
Biometry, the safe key
María Fraile-Hurtado,Miguel Herrero-Langreo,Pilar Menéndez-Miguel,Valerio Delgado-Villanueva
International Journal of Interactive Multimedia and Artificial Intelligence , 2010,
Abstract: Biometry is the next step in authentication, why do not we take this stepforward in our communication security systems? Keys are the main disadvantage in the cryptography, what if we were our own key?
How to avoid mistakes in biometry
Nick Astbury,Balasubramanya Ramamurthy
Community Eye Health Journal , 2006,
Abstract: The refractive power of the human eye depends on three factors: the power of the cornea, the power of the lens, and the length of the eye. Following cataract surgery, only the power of the cornea and the length of the eye are relevant. If both of these variables are known, it is possible to calculate what lens power will give the best refraction. Biometry is the process of measuring the power of the cornea (keratometry) and the length of the eye, and using this data to determine the ideal intraocular lens power. If this calculation is not performed, or if it is inaccurate, then patients may be left with a significant refractive error.
On the change of information technology in the field of Medical Biometry and Statistics
Ro?ner, Reinhard
GMS Medizinische Informatik, Biometrie und Epidemiologie , 2005,
Abstract: An overview on the applications of information technology (IT) in Medical Biometry and Statistics is given using the developments at the Department of Medical Biometry and Statistics in Freiburg for illustration. A description of the fields of applications and of the technical equipment shall provide the basis for pointing out structural changes in the use of IT and in the discipline itself over the last forty years.
Han aumentado el recaudo las reformas tributarias en Colombia?
García Molina, Mario,Gómez , Ana Paola
Revista de Economía Institucional , 2005,
Abstract: En este artículo se evalúa la eficacia de las reformas tributarias efectuadas durante el período 1973-2000 por medio de tres modelos ARIMAX para el recaudo real y la tasa recaudo/PIB. Este análisis, que sólo se incluye las reformas que cambiaron la base o las tarifas, o que buscaban aumentar el recaudo o disminuir la evasión, muestra que apenas dos de las quince reformas consideradas lograron afectar el recaudo: las de 1974 y 1990, con un efecto permanente.
Han aumentado el recaudo las reformas tributarias en Bogotá?  [cached]
García Mario,Parra Yesid
Cuadernos de Economía , 2002,
Abstract: Se estima la eficacia de las reformas tributarias del nivel distrital para el período 1960-2000 por medio de tres modelos ARIMA con una variable de intervención (modelos ARIMAX) para la tasa recaudo/PIB, el recaudo real y el recaudo real per cápita. Sólo se incluyen aquellas reformas que cambiaron la base o las tarifas, o que intentaban aumentar el recaudo o disminuir la evasión. Los modelos muestran que varias de las reformas consideradas fueron exitosas. Como las tres series usadas para medir el recaudo tienen raíz unitaria, el efecto de las reformas exitosas es permanente.
Computational statistics and biometry: which discipline drives which?
Edler, Lutz
GMS Medizinische Informatik, Biometrie und Epidemiologie , 2005,
Abstract: A biometrician's work is defined through the biological or medical problem and the mathematical and statistical methods needed for its solution. This requires in most instances statistical data analysis and the use of methods of computational statistics. At first, it seems quite obvious that the computational needs of the biometric problem determine what has to be developed by the discipline of computational statistics. However, viewing the development of biometry and computational statistics in Germany for the past decades in more details reveals an interesting interaction between the activities of the German Region of the International Biometric Society and groups engaged in computational statistics within Germany. Exact methods of statistical inference and permutation tests, simulations and the use of the Bootstrap, and interactive graphical statistical methods are examples of this fruitful reciprocal benefit. This contribution examines therefore relationships between the historical development of biometry and computational statistics in Germany using as sources of information contributions to the scientific literature, presentations and sessions at scientific conferences on biometry and on computational statistics which influenced the development of both disciplines and exhibits a reciprocal dependency. The annual workshops organized on the Reisensburg now for more than 30 years are recognized as an outstanding factor of this interrelationship. This work aims at the definition of the present status of computational statistics in the German Region of the International Biometric Society and intends to guide and to foster the discussion of the future development of this discipline among biometricians.
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