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1.
Br Poult Sci ; 61(2): 122-131, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31774316

RESUMEN

1. The increase in microbial resistance, and in particular multiple drug resistance (MDR), is an increasing threat to public health. The uncontrolled use of antibiotics and antibacterial chemotherapeutics in the poultry industry, especially in concentrations too low to cause inhibition, and the occurrence of residues in feed and in the environment play a significant role in the development of resistance among zoonotic food-borne microorganisms.2. Determining the presence and transmission methods of resistance in bacteria is crucial for tracking and preventing antibiotic resistance. Horizontal transfer of genetic elements responsible for drug resistance is considered to be the main mechanism for the spread of antibiotic resistance.3. Of the many well-known genetic elements responsible for horizontal gene transfer, integrons are among the most important factors contributing to multiple drug resistance. The mechanism of bacterial drug resistance acquisition through integrons is one of the essential elements of MDR prevention in animal production.


Asunto(s)
Integrones , Aves de Corral , Animales , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Proliferación Celular , Pollos , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/veterinaria
2.
Nature ; 495(7439): 76-9, 2013 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-23467166

RESUMEN

In the era of precision cosmology, it is essential to determine the Hubble constant to an accuracy of three per cent or better. At present, its uncertainty is dominated by the uncertainty in the distance to the Large Magellanic Cloud (LMC), which, being our second-closest galaxy, serves as the best anchor point for the cosmic distance scale. Observations of eclipsing binaries offer a unique opportunity to measure stellar parameters and distances precisely and accurately. The eclipsing-binary method was previously applied to the LMC, but the accuracy of the distance results was lessened by the need to model the bright, early-type systems used in those studies. Here we report determinations of the distances to eight long-period, late-type eclipsing systems in the LMC, composed of cool, giant stars. For these systems, we can accurately measure both the linear and the angular sizes of their components and avoid the most important problems related to the hot, early-type systems. The LMC distance that we derive from these systems (49.97 ± 0.19 (statistical) ± 1.11 (systematic) kiloparsecs) is accurate to 2.2 per cent and provides a firm base for a 3-per-cent determination of the Hubble constant, with prospects for improvement to 2 per cent in the future.

3.
Nature ; 481(7380): 167-9, 2012 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-22237108

RESUMEN

Most known extrasolar planets (exoplanets) have been discovered using the radial velocity or transit methods. Both are biased towards planets that are relatively close to their parent stars, and studies find that around 17-30% (refs 4, 5) of solar-like stars host a planet. Gravitational microlensing, on the other hand, probes planets that are further away from their stars. Recently, a population of planets that are unbound or very far from their stars was discovered by microlensing. These planets are at least as numerous as the stars in the Milky Way. Here we report a statistical analysis of microlensing data (gathered in 2002-07) that reveals the fraction of bound planets 0.5-10 AU (Sun-Earth distance) from their stars. We find that 17(+6)(-9)% of stars host Jupiter-mass planets (0.3-10 M(J), where M(J) = 318 M(⊕) and M(⊕) is Earth's mass). Cool Neptunes (10-30 M(⊕)) and super-Earths (5-10 M(⊕)) are even more common: their respective abundances per star are 52(+22)(-29)% and 62(+35)(-37)%. We conclude that stars are orbited by planets as a rule, rather than the exception.

4.
J Med Primatol ; 46(6): 356-358, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28971470

RESUMEN

This paper describes liver lobe torsion in a white-lipped tamarin (Saguinus labiatus) and an Alaotran gentle lemur (Hapalemur alaotrensis). Both animals had a history of acute collapse, and diagnosis was made post-mortem. To the authors' knowledge, these are the first reported cases of this pathology in non-human primates.


Asunto(s)
Lemuridae , Hepatopatías/veterinaria , Saguinus , Anomalía Torsional/veterinaria , Animales , Hepatopatías/diagnóstico , Hepatopatías/patología , Anomalía Torsional/diagnóstico , Anomalía Torsional/patología
5.
Indian J Otolaryngol Head Neck Surg ; 75(2): 1000-1005, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37275060

RESUMEN

In this article we present a case of a 35-year-old patient with a massive 43 × 35 × 34 mm cavernous venous malformation of the left orbit. The orbital lesion was initially observed in 2008 and remained untreated to 2021 due to the patient's refusal to consent to the surgical procedure; which caused the tumor to grow to monstrous dimensions.

6.
J Physiol Pharmacol ; 74(3)2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37661178

RESUMEN

Glioblastoma, the most common and aggressive type of brain tumor in adults, poses significant challenges in terms of treatment. Conventional approaches including surgery, chemotherapy, and radiotherapy have yielded limited success, with a median survival of approximately 15 months. However, extensive research into the biology of glioblastoma has identified molecular targets that can be exploited by newly developed drugs, leading to the emergence of precise personalized therapies. Several innovative treatment strategies are currently under development, aiming to enhance effectiveness while minimizing side effects. Clinical trials are underway to evaluate the efficacy of monoclonal antibodies that target glioblastoma cells, either by blocking specific receptors or by modifying molecular interactions that impede cell proliferation. Another promising avenue involves the use of oncolytic viruses designed to selectively infect glioblastoma cells. Additionally, the review explores the utilization of nanocarriers capable of surmounting the formidable obstacle of the blood-brain barrier, enabling efficient drug delivery. Cell therapies represent another promising approach, with dendritic cells, chimeric antigen receptor-T cells, and macrophages emerging as potential treatment modalities. By summarizing recent advances in targeted therapies against glioblastoma, this review aims to provide a comprehensive overview of ongoing efforts to discover effective and safe methods for treating glioblastoma patients. The ultimate goal is to improve patient outcomes and transform the landscape of glioblastoma treatment.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Adulto , Humanos , Glioblastoma/tratamiento farmacológico , Barrera Hematoencefálica , Neoplasias Encefálicas/tratamiento farmacológico , Proliferación Celular , Tratamiento Basado en Trasplante de Células y Tejidos
7.
Nature ; 439(7075): 437-40, 2006 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-16437108

RESUMEN

In the favoured core-accretion model of formation of planetary systems, solid planetesimals accumulate to build up planetary cores, which then accrete nebular gas if they are sufficiently massive. Around M-dwarf stars (the most common stars in our Galaxy), this model favours the formation of Earth-mass (M(o)) to Neptune-mass planets with orbital radii of 1 to 10 astronomical units (au), which is consistent with the small number of gas giant planets known to orbit M-dwarf host stars. More than 170 extrasolar planets have been discovered with a wide range of masses and orbital periods, but planets of Neptune's mass or less have not hitherto been detected at separations of more than 0.15 au from normal stars. Here we report the discovery of a 5.5(+5.5)(-2.7) M(o) planetary companion at a separation of 2.6+1.5-0.6 au from a 0.22+0.21-0.11 M(o) M-dwarf star, where M(o) refers to a solar mass. (We propose to name it OGLE-2005-BLG-390Lb, indicating a planetary mass companion to the lens star of the microlensing event.) The mass is lower than that of GJ876d (ref. 5), although the error bars overlap. Our detection suggests that such cool, sub-Neptune-mass planets may be more common than gas giant planets, as predicted by the core accretion theory.

8.
Int J Biol Macromol ; 163: 833-841, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32653378

RESUMEN

The study of the experimental and calculated heat capacity, Cp of fish collagen (silver carp) with contents of several additive components was presented. The experimental low-temperature heat capacity was measured in the temperature range of 1.85 to 302.8 K using a Quantum Design Physical Property Measurement System (PPMS) and the higher temperature Cp from 223.15 K to 382.15 K by Differential Scanning Calorimetry (DSC) method. For an interpretation of the experimental, low-temperature data, the vibrational heat capacity of the pure silver carp collagen was calculated based on the contribution of a sum of the vibrational heat capacity of 4248 amino acids. The vibrational heat capacity for each amino acids was taken from Advanced Thermal Analysis System (ATHAS) Data Bank for individual poly (amino acid) residues based on their group and skeletal vibrational spectra. Comparing of the experimental heat capacity of the collagen with additive components and the calculated vibrational heat capacity of the pure silver carp collagen shows that the differences range from around 10% at 100 K to 14% at 300 K temperature. Such thermal analysis can provide information about the contribution to Cp of unknown components or impurities in the investigated system.


Asunto(s)
Carpas , Colágeno/química , Proteínas de Peces/química , Calor , Algoritmos , Aminoácidos , Animales , Rastreo Diferencial de Calorimetría , Fenómenos Químicos , Modelos Teóricos , Polímeros/química , Termodinámica
9.
Eur Rev Med Pharmacol Sci ; 23(5): 2174-2181, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30915763

RESUMEN

OBJECTIVE: The aim of this study was to analyze the correlation of nicotine dependence with perceived happiness and experienced emotions in three groups, namely non-smokers, smokers, and those who quitted smoking. PATIENTS AND METHODS: The total of 552 Poznan University of Medical Sciences students aged 21.84 ± 3.95 (women: 83.3%, men: 16.7%) participated in this study. They were asked to fill out 4 questionnaires. Two were originally designed by the authors of this paper - one asked about some demographic information and the other described cigarette smoking. Happiness and its dimensions were measured using Fordyce's Happiness Measure and the Positive and Negative Affect Schedule (PANAS). RESULTS: The obtained results point out some significant differences between smokers, non-smokers, and those who quitted smoking as to the levels of negative affect with respects to its two dimensions: Unpleasant and Frustrated. Smokers were characterized by a higher level of a negative affect than non-smokers, as well as higher scores for the Unpleasant and Frustrated dimensions compared to non-smokers and those who quitted smoking. As far as the positive affect of smokers and those who quitted smoking is concerned, a significant difference was observed for 5 dimensions: Interested, Inspired, Attentive, Determined and Active. CONCLUSIONS: The findings of this paper can help us understand better the nicotine-dependent population in the context of positive psychology, and provide us with some basic information helpful in designing preventive programmes for nicotine addicts.


Asunto(s)
Felicidad , No Fumadores/psicología , Fumadores/psicología , Estudiantes de Medicina/psicología , Tabaquismo/epidemiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , No Fumadores/estadística & datos numéricos , Psicología Positiva , Calidad de Vida/psicología , Fumadores/estadística & datos numéricos , Encuestas y Cuestionarios , Tabaquismo/psicología , Adulto Joven
10.
J Physiol Pharmacol ; 70(5)2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31889039

RESUMEN

Currently, many therapies fail due to an insufficient drug dose reaching the target site and high systemic toxicity. Protein-based drug delivery systems that allow an increase in drug concentration at a specific location in the body or predominantly target malignant cells are promising technologies. Due to the high need for iron in many disorders including various types of cancer, iron-binding proteins: transferrin, ferritin and hemoglobin, are a promising tool as drug carriers. In this review we summarize the characteristics of human iron-binding proteins and present their use in targeted drug delivery strategies.


Asunto(s)
Proteínas de Unión a Hierro/metabolismo , Hierro/metabolismo , Animales , Portadores de Fármacos/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo
11.
Eur Rev Med Pharmacol Sci ; 22(11): 3453-3460, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29917198

RESUMEN

OBJECTIVE: The aim of the study was to evaluate the cognitive functioning of children and youth with type 1 diabetes (T1DM). PATIENTS AND METHODS: The study included 68 children with type 1 diabetes, aged 6-17 years, divided into 3 groups according to the level of glycated hemoglobin (HbA1c): group 1: HbA1c ≤ 6.0-7.5%; group 2: HbA1c 7.6-8.5%; group 3: HbA1c over 8.6%. Wechsler's intelligence scale (WISC-R), the Trail of 10 words and Brickenkamp's and Zillmer's d2 Test of Attention were used to assess cognitive functioning. RESULTS: The research demonstrated a significant influence of low, medium or high glycaemic control on lowering the general level of functioning in verbal intelligence, and in WISC-R subtests: information, vocabulary, comprehension, number sequencing and block design. CONCLUSIONS: Children with type 1 diabetes mellitus can experience difficulties in cognitive functioning, as a consequence of high HbA1c. Additional research, involving a larger group of patients and a wider age range when the disease was diagnosed, will enable further findings on the occurrence of cognitive impairment in T1DM.


Asunto(s)
Cognición , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/psicología , Hemoglobina Glucada/metabolismo , Adolescente , Niño , Femenino , Humanos , Masculino , Pruebas Psicológicas/estadística & datos numéricos
13.
Urol Case Rep ; 4: 25-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26793571

RESUMEN

Urothelial carcinomas are the fourth most common tumors in men. Upper tract urinary carcinomas (UTUCs) are uncommon and represent only 5-10% of urothelial carcinomas.(1) Metastatic testicular cancers are rare and primary tumor sources are the prostate, lung, and gastrointestinal tract. We report the first case of testicular metastasis 2 years after initial curative surgery for a high-grade UTUC, all other reported cases weren't proceed by curative surgery.(3).

15.
Pediatrics ; 91(3): 632-6, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8441572

RESUMEN

Single-use diapers and cloth diapers with vinyl pants were compared for their relative abilities to contain stool within the diaper. Artificial feces with carbon black as an additive allowed a quantitative measure of fecal containment by image analysis in 60 infants. This method showed complete containment of feces in the diaper in 50% of the single-use diapers whereas only 10% of the cloth diapers showed complete containment. In infants where the border of the vinyl pants was used as the boundary of containment with the cloth diapers, complete containment occurred only 33% of the time. Fluorescein dye ratings for containment/leakage in 69 infants showed that 83% of single-use diapers and 30% of the cloth diapers were rated as having no or minor leakage of feces. Cultures were taken of laundered vinyl pants that had previously been used over cloth diapers to determine microbial contamination. Thirty-nine percent of the pants contained Gram-negative, lactose-fermenting bacilli indicating fecal contamination. This study comparing single-use and cloth diapers for containment of artificial feces by use of image analysis and fluorescein dye ratings showed better containment by single-use diapers. The study also raises the question of possible spread of feces-borne pathogens by the vinyl pants used over cloth diapers, particularly in a day-care center.


Asunto(s)
Heces , Cuidado del Lactante , Bacterias/aislamiento & purificación , Vestuario , Estudios de Evaluación como Asunto , Heces/microbiología , Femenino , Humanos , Lactante , Masculino
16.
Radiother Oncol ; 62(1): 1-10, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11830307

RESUMEN

BACKGROUND AND PURPOSE: To compare in a phase III study the loco-regional control, disease-free survival and overall survival induced by an accelerated regimen (AF) as compared with conventional regimen (CF) and to analyze the early and late post-radiation morbidity in both arms. MATERIALS AND METHODS: Patients with age < or = 75, WHO 0-1, suitable for a radical course of radiotherapy T1-T3, N0, M0, stage of glottic and supraglottic laryngeal cancer were randomized to either CF: 66Gy given in 33 fractions over 45 days or AF: 66Gy given in 33 fractions over 38 days (2 fractions every Thursday). A total of 395 patients were included from 05.1995 to 12.1998. RESULTS: Early toxicity: At the end of radiotherapy patients treated with AF complained for more severe reactions than patients treated with CF. In 8 weeks after treatment completion patients treated with AF complained only for more severe pain on swallowing (P=0.027). In 4 months after treatment completion all types of toxicity except for skin teleangiectasia (P=0.001) were similar in the two groups. Loco-regional control: comparison between CF and AF showed no difference in terms of loco-regional control (P=0.37). CONCLUSIONS: The improvement in AF in terms of loco-regional control is estimated to be 3-5% in comparison with conventional regimen and is not significant. The intensity of reactions after 4 months was similar in both arms, what suggests the possibility of further shortening of the overall time by few days or enhancing the total dose within the limits of acceptable morbidity.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias Laríngeas/radioterapia , Anciano , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Neoplasias Laríngeas/mortalidad , Neoplasias Laríngeas/patología , Masculino , Terapia Recuperativa , Tasa de Supervivencia , Resultado del Tratamiento
17.
Schizophr Bull ; 25(3): 447-56, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10478780

RESUMEN

Research on the effectiveness of short-term education programs in changing societal attitudes about mental illness has been mixed. Education efforts seem to be mediated by characteristics of the program participants. This study determines whether the effects of a specially prepared, semester-long course on severe mental illness are mediated by pre-education knowledge about and contact with severe mental illness. Eighty-three participants who were enrolled in either a course on severe mental illness or general psychology completed the Opinions about Mental Illness Questionnaire before beginning the course and at completion. Research participants also completed a pre-and posttest of knowledge about mental illness and a pretest on their contact with people who have severe mental illness. The education program had positive effects on some attitudes about mental illness. Interestingly, the effects of education group interacted with pre-education knowledge and contact and varied depending on attitude. Participants with more pre-education knowledge and contact were less likely to endorse benevolence attitudes after completing the education program. Participants with more intimate contact showed less improvement in attitudes about social restrictiveness. Implications of these augmentation and ceiling effects are discussed.


Asunto(s)
Actitud Frente a la Salud , Empatía , Psicología del Esquizofrénico , Estereotipo , Adulto , Autoritarismo , Miedo , Femenino , Educación en Salud , Humanos , Masculino , Estudios Prospectivos , Análisis de Regresión
18.
Schizophr Bull ; 27(2): 187-95, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11354586

RESUMEN

The effects of three strategies for changing stigmatizing attitudes--education (which replaces myths about mental illness with accurate conceptions), contact (which challenges public attitudes about mental illness through direct interactions with persons who have these disorders), and protest (which seeks to suppress stigmatizing attitudes about mental illness)--were examined on attributions about schizophrenia and other severe mental illnesses. One hundred and fifty-two students at a community college were randomly assigned to one of the three strategies or a control condition. They completed a questionnaire about attributions toward six groups--depression, psychosis, cocaine addiction, mental retardation, cancer, and AIDS--prior to and after completing the assigned condition. As expected, results showed that education had no effect on attributions about physical disabilities but led to improved attributions in all four psychiatric groups. Contact produced positive changes that exceeded education effects in attributions about targeted psychiatric disabilities: depression and psychosis. Protest yielded no significant changes in attributions about any group. This study also examined the effects of these strategies on processing information about mental illness.


Asunto(s)
Actitud Frente a la Salud , Educación en Salud , Relaciones Interpersonales , Trastornos Mentales/psicología , Defensa del Paciente , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Adulto , Chicago , Femenino , Humanos , Masculino , Trastornos Mentales/diagnóstico , Prejuicio , Estudiantes/psicología
19.
Psychiatr Serv ; 52(7): 953-8, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11433114

RESUMEN

OBJECTIVES: This study examined the effects of familiarity with and social distance from persons who have serious mental illness on stigmatizing attitudes about mental illness. METHODS: A total of 208 community college students completed three written measures about familiarity, perception of dangerousness, fear, and social distance. Path analysis with manifest-variable structural modeling techniques was used to test a version of a model in which familiarity influences the perception of dangerousness, which in turn influences fear, which influences social distance from persons with serious mental illness. RESULTS: Most of the participants reported experience with mental illness. Scores on the three written measures largely supported the path model. Correlations between the perception of dangerousness and fear as well as between fear and social distance were particularly strong. CONCLUSIONS: Approaches to social change that increase the public's familiarity with serious mental illness will decrease stigma. Further studies are warranted that focus on how contact between members of the general public and persons who have serious mental illness may be facilitated.


Asunto(s)
Miedo/psicología , Trastornos Mentales/psicología , Distancia Psicológica , Reconocimiento en Psicología , Percepción Social , Adulto , Actitud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estereotipo , Encuestas y Cuestionarios , Estados Unidos
20.
Science ; 345(6192): 46-9, 2014 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-24994642

RESUMEN

Using gravitational microlensing, we detected a cold terrestrial planet orbiting one member of a binary star system. The planet has low mass (twice Earth's) and lies projected at ~0.8 astronomical units (AU) from its host star, about the distance between Earth and the Sun. However, the planet's temperature is much lower, <60 Kelvin, because the host star is only 0.10 to 0.15 solar masses and therefore more than 400 times less luminous than the Sun. The host itself orbits a slightly more massive companion with projected separation of 10 to 15 AU. This detection is consistent with such systems being very common. Straightforward modification of current microlensing search strategies could increase sensitivity to planets in binary systems. With more detections, such binary-star planetary systems could constrain models of planet formation and evolution.

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