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Search Results: 1 - 10 of 39073 matches for " Luis Guillermo Guerrero Ramirez "
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Polymeric Nanohydrogels of Poly(N-Isopropylacrylamide) Combined with Others Functionalized Monomers: Synthesis and Characterization  [PDF]
Lissette Agüero Luztonó, Yuneivy Cepero Donates, Luis Guillermo Guerrero Ramirez, Addys González Palomo, Dionisio Zaldivar Silva, Issa Katime
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2014, DOI: 10.4236/jbnb.2014.51005

Nanohydrogels from inverse microemulsion (w/o) polymerization, at 25°C, of N-isopropylacrylamide (NIPA) and functionalized monomers are described. The functionalized monomers were: N-(pyridine-4-ylmethyl) acrylamide (NP4MAM) and tert-butyl 2-acrylamidoethyl carbamate (2AAECM). The polymeric nanohydrogel obtained was characterized by attenuated total reflectance Fourier-transformed infrared spectroscopy (ATR-FTIR) and proton nuclear magnetic resonance spectrometry (1HNMR), while their morphology and particle size was assessed by scanning electron microscopy (SEM) and dynamic light scattering. Their thermal properties were studied by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). As a preliminary measure of biocompatibility, in vitro evaluations of the nanohydrogels were carried out by cellular toxicity (colon carcinoma cells, CT

Calcificación de aorta abdominal de pacientes en hemodiálisis en una unidad renal
Valderrama,Luis A; Guerrero,Luis Fernando; Bolívar,Guillermo;
Acta Medica Colombiana , 2012,
Abstract: objective: to describe the prevalence of abdominal aortic calcifications and risk factors in patients on hemodialysis in the renal unit imbanaco medical center in the city of cali. background: vascular calcification is prevalent in patients with chronic kidney disease. hemodialysis (hd) patients are at increased risk of cardiovascular mortality and factors such as age, associated diseases and some metabolic abnormalities increase the risk of vascular calcification. material and methods: we included 47 hemodialysis patients over 18 years and more than three months in dialysis. the lateral lumbar radiography was used to assess the calcification of the segments l1 to l4 using a score for quantification and a single trained observer. regression analysis was used to determine associations between aac and patient characteristics. results: median age of patients was 60.8 years (range 25-84), 57.4% were female, median duration of hd 44.6 months (range 3-156). we found that in 63.8% of patients had calcifications in any segment of the abdominal aorta. we found that older age (p = 0.0006) and lower diastolic blood pressure (dbp) (p = 0.036) the risk is greater prevalence of calcification. conclusions: abdominal aortic calcification is prevalent in patients with ckd on hemodialysis. factors such as age and decreased dbp were associated with the group of calcifications.the lateral lumbar radiograph is a tool widely available and less expensive than can be taken into account in the assessment of cardiovascular risk in hemodialysis patients and as a predictor of complications. (acta med colom 2012; 37: 14-20).
Calcificación de aorta abdominal de pacientes en hemodiálisis en una unidad renal Calcification of the abdominal aorta in patients on hemodialysis in a renal unit
Luis A Valderrama,Luis Fernando Guerrero,Guillermo Bolívar
Acta Medica Colombiana , 2012,
Abstract: Objetivo: describir la prevalencia de calcificaciones de aorta abdominal y factores de riesgo relacionados de pacientes en hemodiálisis en una unidad renal de la ciudad de Cali. Introducción: las calcificaciones vasculares son prevalentes en pacientes con enfermedad renal crónica (ERC). Los pacientes en hemodiálisis presentan mayor riesgo de mortalidad cardiovascular y factores como la edad, enfermedades asociadas y algunas alteraciones metabólicas incrementan el riesgo de calcificaciones vasculares. Material y métodos: se incluyeron 47 pacientes en hemodiálisis mayores de 18 a os y con más de tres meses en hemodiálisis. La radiografía lumbar lateral fue usada para evaluar las calcificaciones de los segmentos L1 a L4 utilizando un puntaje para su cuantificación y un único observador entrenado. Se realizaron mediciones de calcio, fósforo, PTH, colesterol, triglicéridos en sangre y tensión arterial. Fue utilizado análisis de regresión para determinar asociaciones entre las calcificaciones de aorta abdominal y las características de los pacientes. Resultados: se encontró que la edad promedio fue de 60,8 a os (rango 25-84), el 57.4% fueron mujeres, el tiempo promedio en hemodiálisis 44.6 meses (rango 3-156). El 63.8% de los pacientes presentaron calcificaciones en algún segmento de la aorta abdominal. Se encontró que a mayor edad (P = 0.0006) y menor tensión arterial diastólica (TAD) (P = 0.036), el riesgo de prevalencia de calcificación es mayor. Conclusiones: la calcificación de aorta abdominal es prevalente en los pacientes con ERC en hemodiálisis. Factores como la edad y la disminución de la TAD se encontraron asociadas al grupo de calcificaciones. La radiografía lumbar lateral es una herramienta ampliamente disponible y menos costosa que puede ser tenida en cuenta en el tratamiento y evaluación de riesgo cardiovascular en los pacientes en hemodiálisis y como predictor de complicaciones. (Acta Med Colom 2012; 37: 14-20). Objective: to describe the prevalence of abdominal aortic calcifications and risk factors in patients on hemodialysis in the renal unit Imbanaco Medical Center in the city of Cali. Background: vascular calcification is prevalent in patients with chronic kidney disease. Hemodialysis (HD) patients are at increased risk of cardiovascular mortality and factors such as age, associated diseases and some metabolic abnormalities increase the risk of vascular calcification. Material and methods: we included 47 hemodialysis patients over 18 years and more than three months in dialysis. The lateral lumbar radiography was used to assess the calcific
Algoritmos Voraces
Guillermo Solarte Martinez,Luis Eduardo Mu?oz Guerrero
Scientia Et Technica , 2007,
Abstract: Los algoritmos voraces son usados esencialmente para resolver problemas de optimización, aunque también pueden aproximarse a una solución a problemas considerados computacionalmente difíciles, Son algoritmos muy fácil de dise ar e implementar y de gran eficiencia.
Carbadox Intoxication in Pigs
Ramiro Ramirez Necoechea,Alicia Magdalena Nevarez Garza,Luis Edgar Rodriguez Tovar,Guillermo Davalos Aranda,Jose Francisco Hernandez Ramirez,Rafael Ramirez Romero
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2010.85.87
Abstract: The aim of this study is to present the clinical and pathological findings occurring in a natural outbreak of Carbadox poisoning in pigs. Carbadox was administrated as much as four times the recommended dose (210 ppm) at least during the fattening period. Clinical signs included emaciation, dry feces, pica, ataxia, tremor and nervousness in some animals. Postmortem examination showed dehydration, gastric ulcers, bronchopneumonia, hydrothorax and hydropericadium. Microscopically, the most significant lesions were atrophy of glomerulosa zone in the adrenals with hydropic degeneration and necrosis of the remaining cells. Diagnosis was based on clinical history and lesions in the adrenal cortex, which are considered characteristics.
Universal Regularizers For Robust Sparse Coding and Modeling
Ignacio Ramirez,Guillermo Sapiro
Mathematics , 2010,
Abstract: Sparse data models, where data is assumed to be well represented as a linear combination of a few elements from a dictionary, have gained considerable attention in recent years, and their use has led to state-of-the-art results in many signal and image processing tasks. It is now well understood that the choice of the sparsity regularization term is critical in the success of such models. Based on a codelength minimization interpretation of sparse coding, and using tools from universal coding theory, we propose a framework for designing sparsity regularization terms which have theoretical and practical advantages when compared to the more standard l0 or l1 ones. The presentation of the framework and theoretical foundations is complemented with examples that show its practical advantages in image denoising, zooming and classification.
Variations of the origin of collateral branches emerging from the posterior aspect of the brachial plexus
Luis Ballesteros, Luis Ramirez
Journal of Brachial Plexus and Peripheral Nerve Injury , 2007, DOI: 10.1186/1749-7221-2-14
Abstract: The anatomy of brachial plexus structures from 46 male and 11 female cadaverous specimens were studied. The 40–80 year-old specimens were obtained from the Universidad Industrial de Santander's Medical Faculty's Anatomy Department (dissection laboratory). Parametric measures were used for calculating results.Almost half (47.1%) of the evaluated plexuses had collateral variations. Subscapular nerves were the most varied structure, including the presence of a novel accessory nerve. Long thoracic nerve variations were present, as were the absence of C5 or C7 involvement, and late C7 union with C5–C6.Further studies are needed to confirm the existence of these variations in a larger sample of cadaver specimens.Brachial plexus (BP) anatomical variations have been described in humans by many authors, although such variations have not been extensively catalogued [1-4]. Variations in plexus patterns may be due to unusual formation during the development of trunks, divisions, or cords [5]. The more common BP variations occur at the junction or separation of the individual parts [6,7]. Peripheral (collateral) nerves arise from the whole plexus trajectory. These collaterals reach proximal regions exclusively innervating some scapular belt muscles.Anesthetic blocks, surgical approaches, the interpretation of a nervous compression having unexplained clinical symptoms (sensory loss, pain, wakefulness and paresis), and these structures being compromised represent the clinical importance of these variations [8,9]. Dorsal scapular, long thoracic, suprascapular, subscapularis and thoracodorsal origins were studied to show variable BP collateral arrangements.BP structures from 46 male and 11 female mixed-race, cadaverous specimens (40–80 years old) were studied. These specimens were obtained from the Medical Faculty's Department of Anatomy (dissection laboratory) at Universidad Industrial de Santander during academic semesters in 2005 and 2006. The cause of death for each cadaver was
Possible implications of an accessory abductor digiti minimi muscle: a case report
Luis Ballesteros, Luis Ramirez
Journal of Brachial Plexus and Peripheral Nerve Injury , 2007, DOI: 10.1186/1749-7221-2-22
Abstract: This case report presents a bilateral variation of an accessory abductor digiti minimi muscle in a male specimen. Ulnar artery and ulnar nerves were taken into account regarding their position and trajectory related to this variation.Muscle size may be an important factor in considering whether a variation is able to produce neurovascular compression and clinical implications.This case report presents an abductor digiti minimi (ADM) muscle's bilateral accessory head, involving ulnar artery (UA) and ulnar nerve (UN) trajectories' sensorial and motor components. Although muscular, vascular and nervous variations of the hypothenar eminence are rare (differing from anomalous muscles in the wrist), they have been reported [1-10]. According to Sheppard, three cases of accessory ADM were first reported by Wood in 1868. Most authors call such additional ADM head an "accessory" component which can be unilaterally or bilaterally presented, producing compression in Guyon's canal. Harvie et al., found an accessory ADM in 41% of 116 volunteers' asymptomatic ultrasound examinations, greater prevalence being found in male samples and bilateral presentation in 50% of cases for both genders.The flexor digiti minimi brevis muscle can also be present in this area; Madhavi et al., have stated that it relates to the common phylogeny of these muscles from the same muscle mass [11]. Soldado-Carrera et al., found this variation to be associated with decreased flexor digitorum superficialis muscle fourth tendon caliper and median nerve split. Murata [7] found an accessory ADM in 35 hands, having one (17%), two (80%) and three fascicles (3%). Furthermore, Wulle [8] presented eleven cases of accessory ADM, but having "longus" presentation.This case report arises from one cadaver specimen amongst a sample of thirty which were obtained from Universidad Industrial de Santander's Medical Faculty's Anatomy Department (dissection laboratory) during 2006 academic semesters. The specimen was fixed in
Absence of Bovine Leukocyte Adhesion Deficiency (BLAD) in Holstein Cattle from Mexico
Victor M. Riojas-Valdes,Barbara Carballo-Garcia,Luis E. Rodriguez-Tovar,Martha V. Garza-Zermeno,Rafael Ramirez-Romero,Juan Zarate-Ramos,Ramiro Avalos-Ramirez,Guillermo Davalos-Aranda
Journal of Animal and Veterinary Advances , 2012,
Abstract: Bovine leukocyte adhesion deficiency is an autosomal recessive genetic disease that produces in many cases the early death of Holstein calves, causing economic losses to milk producers and breeders. It is due to a point mutation in position 383 of cDNA of the CD18 gene, leading to a substitution of guanine for adenine and a change of glycine for aspartic acid (position 128). As a consequence, the normal CD11B/CD18 integrine is not functional. The affected animals show recurrent bacterial infections, delayed wound healing, stunted growth and early death. Many countries have followed a policy of detecting carrier bulls with a DNA test in order to eliminate them from Artificial Insemination (AI) programs with great success. In Mexico, no carrier detection program has been implanted, although, most of bulls used for AI comes from the USA, country that have done screening programs for the last 10 years. In order to determine the gene frequency of the BLAD mutation in Northeast Mexico, 61 Holstein animals were analyzed by PCR-RFLP. No evidence of the mutation was found, indicating that the use of USA, BLAD-free bulls in AI programs has probably eliminated the disease in Holstein population in Mexico.
Trabajo, salud y régimen contractual en personal de enfermería: un enfoque psicosocial
Avances en Enfermería , 2010,
Abstract: associated cooperativism has been the favorite mechanism of labor flexibilization in the colombian health system. in spite of the multiple references to the deleterious effects on working conditions, no specific research has been conducted about the effects on nursing staffs. this research is intended to define and compare the working and health conditions of the auxiliary and professional nursing staff according to the contractual modality and other relevant socio-labor conditions. 290 professional and auxiliary nurses from a highly complex public hospital located in bogota attached to the network of hospitals of the district health secretariat were subject to a psychosocial interview derived from instruments designed or adapted by the line of research “psychosocial approach of the health-labor relation”, of the national university. the lipid profile of 176 participants was also measured. the results show that human resources policies (contracts, salary, promotions, occupational health, training, leisure, etc.) are factors that cast the major negative influence on the welfare of nursing staffs, mainly in cooperative and professional ones. particularly, the results present the main working conditions risk-protection profiles through the conglomeration of intra-labor, extra-labor, individual factors or macro-factors.
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