Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 101
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Energy Policy ; 126: 391-401, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32161429

RESUMEN

There is a growing literature on the potential contributions the global forest sector could make toward long-term climate action goals through increased carbon sequestration and the provision of biomass for energy generation. However, little work to date has explored possible interactions between carbon sequestration incentives and bioenergy expansion policies in forestry. This study develops a simple conceptual model for evaluating whether carbon sequestration and biomass energy policies are carbon complements or substitutes. Then, we apply a dynamic structural model of the global forest sector to assess terrestrial carbon changes under different combinations of carbon sequestration price incentives and forest bioenergy expansion. Our results show that forest bioenergy expansion can complement carbon sequestration policies in the near- and medium-term, reducing marginal abatement costs and increasing mitigation potential. By the end of the century these policies become substitutes, with forest bioenergy expansion increasing the costs of carbon sequestration. This switch is driven by relatively high demand and price growth for pulpwood under scenarios with forest bioenergy expansion, which incentivizes management changes in the near- and medium-term that are carbon beneficial (e.g., afforestation and intensive margin shifts), but requires sustained increases in pulpwood harvest levels over the long-term.

2.
Dyslexia ; 16(3): 194-212, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20680991

RESUMEN

Three major 'neural systems', specialized for different types of information processing, are the sensory, declarative, and procedural systems. It has been proposed (Trends Neurosci., 30(4), 135-141) that dyslexia may be attributable to impaired function in the procedural system together with intact declarative function. We provide a brief overview of the increasing evidence relating to the hypothesis, noting that the framework involves two main claims: first that 'neural systems' provides a productive level of description avoiding the underspecificity of cognitive descriptions and the overspecificity of brain structural accounts; and second that a distinctive feature of procedural learning is its extended time course, covering from minutes to months. In this article, we focus on the second claim. Three studies-speeded single word reading, long-term response learning, and overnight skill consolidation-are reviewed which together provide clear evidence of difficulties in procedural learning for individuals with dyslexia, even when the tasks are outside the literacy domain. The educational implications of the results are then discussed, and in particular the potential difficulties that impaired overnight procedural consolidation would entail. It is proposed that response to intervention could be better predicted if diagnostic tests on the different forms of learning were first undertaken.


Asunto(s)
Encéfalo/fisiopatología , Desarrollo Infantil , Dislexia/fisiopatología , Desarrollo del Lenguaje , Aprendizaje/fisiología , Encéfalo/crecimiento & desarrollo , Cerebelo/crecimiento & desarrollo , Cerebelo/fisiopatología , Niño , Preescolar , Dislexia/psicología , Humanos , Lactante , Práctica Psicológica
3.
Aust Vet J ; 98(7): 326-332, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32662531

RESUMEN

Knowledge of the most common presenting complaints and diagnoses in companion animals is valuable in preparing veterinary students and veterinarians to manage the most frequently observed conditions in clinical practice. Pet insurance databases provide access to large sample populations and have been previously used to describe disease incidence in companion animals. The aim of this study was to determine the incidence of presenting complaints and diagnoses in insured Australian dogs through the use of a pet insurance database. Analysis of a de-identified dataset containing pet insurance claims associated with presenting complaints and diagnoses from 488,472 insured Australian dogs insured in the years 2016 and 2017, was performed. Annual incidence rates of presenting complaints and diagnoses were calculated and expressed as, number of events per 1,000 dog years at risk. The presenting complaints with the highest incidence were vomiting (14.21 events per 1,000 dog years at risk in 2016, 15.80 events per 1,000 dog years at risk in 2017) and pruritus (8.79 events per 1,000 dog years at risk in 2016, 10.30 events per 1,000 dog years at risk in 2017). Presenting complaints affecting the gastrointestinal system were the most common (19.20 events per 1,000 dog years at risk in 2016, 20.77 events per 1,000 dog years at risk in 2017). The diagnoses with the highest incidence were otitis externa (34.12 events per 1,000 dog years at risk in 2016, 34.82 events per 1,000 dog years at risk in 2017) and dermatitis (28.05 events per 1,000 dog years at risk in 2016, 29.99 events per 1,000 dog years at risk in 2017). Diagnoses affecting the integument were the most common (216.56 events per 1,000 dog years at risk in 2016, 219.06 events per 1,000 dog years at risk in 2017). The results from this study can aid in the design of relevant veterinary curricula and may be helpful in prioritising research on common clinical conditions.


Asunto(s)
Enfermedades de los Perros , Veterinarios , Animales , Australia , Bases de Datos Factuales , Perros , Humanos , Incidencia
4.
Aust Vet J ; 98(8): 356-363, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32458445

RESUMEN

OBJECTIVE: Veterinarians have an important role in supporting and understanding their clients' grief. Veterinary schools have a duty to teach students how best to manage grief - both that of the students/future veterinarians and the clients. This study explores how grief management, associated with ending the life of an animal, was taught to students in eight Australasian veterinary schools. METHODS: A questionnaire-style interview guide was used by a representative at each university to conduct structured interviews with educators in a snowball sampling approach. Educators were interviewed about the teaching of grief management for four categories of animals: livestock, equine, companion and avian/wildlife. The terms used by participants to describe what they taught were grouped into common themes. Teaching was defined by individual participants and included structured and unstructured approaches. The stage in the degree (preclinical or clinical years) that grief management was taught in the veterinary curriculum and by whom (e.g. clinicians or psychologists) is also described. RESULTS: Grief management was taught more in preclinical than clinical years. However, due to how grief was characterised, much of this teaching was general 'nonspecific' teaching that included all categories of animals. Client grief was taught more generically, whereas, grief of veterinarians was taught using specific examples given by clinicians. CONCLUSION: A more robust end-of-life (EoL) management curriculum that includes all aspects of grief management is likely to increase job satisfaction, client happiness and professional satisfaction.


Asunto(s)
Educación en Veterinaria , Veterinarios , Animales , Curriculum , Pesar , Caballos , Humanos , Facultades de Medicina Veterinaria , Estudiantes
5.
Aust Vet J ; 97(10): 373-381, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31310017

RESUMEN

AIM: To measure the stress levels of Doctor of Veterinary Medicine (DVM) students at the University of Sydney using the Kessler Psychological Distress Scale (K10) questionnaire. METHODS: DVM students in years 1 to 4 were surveyed in semester 2 of 2018. The voluntary online survey consisted of 6 demographic questions and the K10 scale, a standardised measure of stress commonly used in Australia by medical practitioners for evaluation and referral to mental health professionals. Academic year cohorts were compared to identify differences in stress levels. Cohorts were compared to published K10 scores from various populations including the Australian public, medical students, practicing veterinarians, and Junior Medical Officers (JMOs). RESULTS: The response rate was 54.4% (n = 237). DVM students experienced a higher level of psychological distress (mean 24, median 23, range 10-50) than the Australian population (mean 14.5, median 13, range 10-50), medical students (mean 18.4, median 16, range 10-50), practicing veterinarians (mean 16.7, median 15.5, range 10-30), and JMOs (mean 18.1, median 16, range 10-50). Female students (median 23) had a significantly higher level of psychological distress compared to male students (median 18) (p = 0.0005). International students (median 23) had a higher level of psychological stress than domestic students (median 22) (p = 0.0488). Different year cohorts, age range, work hours, and exercise were not associated with difference in stress levels. CONCLUSION: Based on higher levels of stress in DVM students than that of the general population, practicing veterinarians, JMOs and medical students, there is an urgent need for evidence-based interventions to target stress in DVM students.


Asunto(s)
Distrés Psicológico , Estrés Psicológico/epidemiología , Estudiantes del Área de la Salud/psicología , Adulto , Análisis de Varianza , Australia/epidemiología , Femenino , Humanos , Internado y Residencia , Masculino , Nueva Gales del Sur/epidemiología , Facultades de Medicina Veterinaria , Distribución por Sexo , Estudiantes de Medicina/psicología , Encuestas y Cuestionarios , Veterinarios/psicología , Adulto Joven
6.
Clin Neurophysiol ; 118(4): 845-55, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17317301

RESUMEN

OBJECTIVE: To investigate whether attentional difficulties are a "core" feature of developmental Dyslexia. METHODS: Behavioural indices and event related potentials (ERPs) were recorded from 10 dyslexic participants (ages 15.5-17.4) and 10 control participants (ages 14.4-18.3) in the Continuous Performance Task (CPT), an established test of attentional performance. Participants were screened to ensure that none was diagnosable as attention deficit (ADHD). RESULTS: There were no significant differences in mean reaction time, error rate or sustained attention between the groups. By contrast, the P3 amplitude was significantly smaller and its latency significantly longer for the dyslexic group. This component was significantly lateralised in controls, whereas in dyslexics it was symmetrical. CONCLUSIONS: Under the relatively light workload conditions of the CPT, "pure" dyslexic participants showed no behavioural signs of attentional difficulties. The attenuated, delayed and symmetrical ERPs in our dyslexic group may reflect abnormal information processing in the right parietal lobe and abnormal interhemispheric asymmetry in Dyslexia. SIGNIFICANCE: The behavioural data suggest that abnormal attentional performance is not a "core" feature of developmental Dyslexia, and highlight the importance of distinguishing between dyslexic participants with and without ADHD symptoms. The presence of electrophysiological markers of Dyslexia in CPT revealed the atypical brain organisation that characterises "pure" Dyslexia.


Asunto(s)
Atención , Conducta/fisiología , Dislexia/fisiopatología , Potenciales Relacionados con Evento P300/fisiología , Pruebas Neuropsicológicas , Adolescente , Análisis de Varianza , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Desempeño Psicomotor/fisiología , Tiempo de Reacción
7.
Aust Vet J ; 95(6): 189-193, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28555952

RESUMEN

OBJECTIVE: To determine what veterinary students in Australia and New Zealand consider important competences in companion animal welfare and ethics (AWE) required on their first day of practice, and to explore how their priorities relate to gender and stage of study. METHODS: Undergraduate students at all veterinary schools in Australia and New Zealand were sent an online survey. A subset of questions required participants to rank the importance of preselected AWE topics pertaining to companion animals. Data were analysed to determine differences in the way students of different gender or academic stage prioritised each of these AWE topics. RESULTS: Of 3220 currently enrolled students, 851 participated in the survey: 79% were female, 17% male, 4% unspecified. Ranking of the AWE topics, from highest to lowest importance, was: neutering, companion animal husbandry, euthanasia, behaviour and training, animal breeding, over-servicing in relation to animal needs and cosmetic surgery. Female students consistently ranked competency in AWE issues surrounding neutering more highly than male students (P = 0.006). Students in senior years of study ranked the importance of competency in animal abuse/hoarding (P = 0.048), shelter medicine (P = 0.012) and animal breeding (P = 0.002) less highly than those in junior years. CONCLUSIONS: Australasian veterinary students placed more importance on competency in AWE issues associated with clinical practice (such as neutering and euthanasia) than on professional behaviours (such as over-servicing and animal breeding). However, we consider that emphasis should still be placed on developing graduate competency in the latter categories to reflect growing societal concerns about companion animal over-supply and inappropriate professional conduct.


Asunto(s)
Crianza de Animales Domésticos , Bienestar del Animal , Actitud , Estudiantes/psicología , Crianza de Animales Domésticos/ética , Bienestar del Animal/ética , Animales , Australia , Competencia Clínica , Eutanasia Animal , Femenino , Humanos , Internet , Masculino , Nueva Zelanda , Mascotas , Facultades de Medicina Veterinaria , Distribución por Sexo , Esterilización Reproductiva/psicología , Esterilización Reproductiva/veterinaria , Encuestas y Cuestionarios
8.
Trends Neurosci ; 24(9): 508-11, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11506881

RESUMEN

Surprisingly, the problems faced by many dyslexic children are by no means confined to reading and spelling. There appears to be a general impairment in the ability to perform skills automatically, an ability thought to be dependent upon the cerebellum. Specific behavioural and neuroimaging tests reviewed here indicate that dyslexia is indeed associated with cerebellar impairment in about 80% of cases. We propose that disorders of cerebellar development can in fact cause the impairments in reading and writing characteristic of dyslexia, a view consistent with the recently appreciated role of the cerebellum in language-related skills. This proposal has implications for early remedial treatment.


Asunto(s)
Enfermedades Cerebelosas/psicología , Cerebelo/fisiopatología , Dislexia/psicología , Animales , Enfermedades Cerebelosas/fisiopatología , Dislexia/fisiopatología , Humanos
9.
J Neural Transm Suppl ; (69): 19-36, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16355601

RESUMEN

Theoretical frameworks for dyslexia must explain how the well-established phonological deficits and the literacy deficits arise. Our longstanding research programme has led to a distinctive 'twin level' framework that proposes, first, that the core deficits are well described in terms of poor skill automaticity. Second, these 'cognitive level' symptoms are attributed to abnormal cerebellar function--a 'brain-level' analysis. The evidence includes data from behavioural, imaging, neuroanatomical and learning studies. The frame-work leads to an 'ontogenetic' analysis that links cerebellar deficit at birth, via problems in articulation and working memory, to the known phonological, speed and literacy difficulties. Differences in locus of cerebellar impairment, experience and/or links to other brain regions may account for subtypes of dyslexia and possibly other developmental disorders. The automaticity/ cerebellar deficit framework provides an explicit demonstration that it is possible to explain motor, speed and phonological deficits within a unified account, integrating previously opposed approaches.


Asunto(s)
Cerebelo/fisiopatología , Dislexia/fisiopatología , Dislexia/psicología , Aprendizaje , Enfermedades Cerebelosas/fisiopatología , Humanos
10.
Vet Rec ; 156(22): 695-702, 2005 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-15923551

RESUMEN

A study was undertaken to determine the prevalence of obesity in dogs examined by veterinary practices across Australia, and to determine the risk factors involved; 1700 practices were asked to complete a veterinarian opinion survey, and of the 428 practices that responded, 178 were selected to complete an RSPCA Australia Pet Obesity Questionnaire, together with additional practices selected by Australian State and Territory RSPCA societies. This questionnaire was sent to a total of 209 practices which were asked to record details of eligible dogs, and the reason why they had been examined during the previous month. Fifty-two (24.9 per cent) of the practices responded and provided data on 2661 dogs, of which 892 (33.5 per cent) were overweight and 201 (7.6 per cent) were obese. A further 112 dogs (4.2 per cent) were classified as thin or very thin, but these were excluded from subsequent analyses. Of the remaining 2549 dogs, approximately half were female and 1905 (74.7 per cent) were neutered. The dogs' weight category was influenced by several factors. Breed influenced the importance of sex and neutering as risk factors. The prevalence of overweight and obese dogs combined was 41 per cent; the prevalence increased with age up to about 10 years old, and then declined. Rural and semirural dogs were more at risk of obesity than urban and suburban dogs.


Asunto(s)
Enfermedades de los Perros/epidemiología , Obesidad/veterinaria , Factores de Edad , Animales , Australia/epidemiología , Cruzamiento , Castración/efectos adversos , Castración/veterinaria , Enfermedades de los Perros/etiología , Perros , Femenino , Geografía , Masculino , Obesidad/epidemiología , Obesidad/etiología , Prevalencia , Factores de Riesgo , Factores Sexuales , Encuestas y Cuestionarios
11.
Proc Biol Sci ; 259(1354): 43-7, 1995 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-7700875

RESUMEN

In addition to their language-related difficulties, dyslexic children suffer problems in motor skill, balance, automatization and speeded performance. Given the recent evidence for cerebellar involvement in the acquisition of language fluency, these problems suggest cerebellar deficit. To test the hypothesis of cerebellar dysfunction in dyslexia, a time estimation task considered to be a sensitive index of cerebellar function was administered to matched groups of dyslexic and control children. The dyslexic children showed the predicted deficit on time estimation (among the most severe obtained in our research programme) but not on a control, loudness estimation, task. Cerebellar dysfunction, therefore, provides a parsimonious account of otherwise disparate data on deficits in dyslexia.


Asunto(s)
Cerebelo/fisiopatología , Dislexia/fisiopatología , Percepción del Tiempo , Estimulación Acústica , Adolescente , Niño , Humanos , Percepción Sonora , Psicometría , Desempeño Psicomotor , Umbral Sensorial
12.
Cognition ; 35(2): 159-82, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2354611

RESUMEN

The performance of a group of 23 13-year-old dyslexic children was compared with that of same-age controls on a battery of tests of motor balance. A dual-task paradigm was used--subjects performed each test twice, once as a single task, and once as a dual task concurrently with a secondary task. Two alternative secondary tasks were used, the classic counting-backwards task and an auditory choice reaction task. Both secondary tasks were calibrated for each subject to ensure that their performance on the secondary task alone fell between pre-specified performance criteria. In all single-task conditions there was no difference between the performance of the two groups. By contrast, in 19 out of the 20 tests performed under dual-task conditions, the dyslexic group were significantly impaired, whereas the controls showed no impairment, thus resulting in significantly better performance by the control group than the dyslexic group. The sole exception was that the dyslexic children were not impaired on the easiest balance condition with the choice reaction task. Under the dual-task conditions the dyslexic children also performed worse than the controls on the secondary task. It is very hard to accommodate the findings within the traditional framework of a deficit specific to lexical skills. One plausible explanation of the results is that, unlike the controls, the dyslexic children need to invest significant conscious resources for monitoring balance, and thus their performance is adversely affected by any secondary task which serves to distract attention from the primary task. This need for "conscious compensation" suggests that for dyslexic children the skill of motor balance is poorly automatized. It is possible, therefore, that many of the reading deficits of dyslexic children are merely symptoms of a more general learning deficit--the failure to fully automatize skills.


Asunto(s)
Atención , Dislexia/psicología , Memoria , Retención en Psicología , Adolescente , Concienciación , Niño , Femenino , Humanos , Masculino , Destreza Motora , Equilibrio Postural
13.
J Clin Pathol ; 54(9): 718-20, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11533082

RESUMEN

A 60 year old woman who presented with dysphagia and weight loss was found to have multiple foci of dysplasia and in situ and invasive squamous cell carcinoma scattered along the whole length of the oesophagus, with intervening areas of normal mucosa. The patient had a history of two breast carcinomas 19 and one year previously for which she had repeated radiotherapy. Several members of the patient's close family had histories of malignant disease. All oesophageal lesions and the more recent breast cancer showed positive immunostaining for p53 protein. p53 mutations, some involving different exons, were also detected in these lesions. No p53 immunostaining or mutations were detected in the normal oesophageal mucosa. The findings suggest an independent origin of the multiple dysplastic and neoplastic foci, which might have developed in a background of a field change, possibly related to the previous radiotherapy. The strong family history of malignant diseases raises the possibility that, in addition, genetic factors might have played a role in the development of the oesophageal disease.


Asunto(s)
Neoplasias de la Mama/radioterapia , Carcinoma de Células Escamosas/etiología , Neoplasias Esofágicas/etiología , Neoplasias Inducidas por Radiación/etiología , Neoplasias Primarias Secundarias/etiología , Resultado Fatal , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad
14.
J Appl Physiol (1985) ; 63(3): 962-8, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3654476

RESUMEN

Blood flow was measured in leg and torso skin of conscious or anesthetized sheep by using 15-micron radioactive microspheres (Qm) and the 133Xe washout method (QXe). There was a good relationship between Qm in the cutaneous compartment and QXe calculated from the fast component of the biexponential washout curves (QXe = 0.40.Qm + 6.2, r = 0.90, P less than 0.001) with QXe values substantially below those determined with microspheres. Only at low blood flow levels was there a tendency for QXe to overestimate capillary blood flow as assessed with microspheres, but at higher blood flow levels the 133Xe washout method resulted in values substantially below those determined with microspheres. The slope of the slow component of the washout curves was inversely related to the tissue-blood partition coefficient in the subcutaneous tissue (r = 0.52, P less than 0.001), indicating an influence of the amount of subcutaneous fat on the washout rate. QXe calculated from the slow component of the washout curves was not significantly correlated with Qm in the subcutaneous compartment (r = 0.19, P greater than 0.10). In leg skin with dilated arteriovenous anastomoses, QXe was generally higher than in torso skin and leg skin with constricted arteriovenous anastomoses, indicating that shunt blood flow increases the washout of 133Xe.


Asunto(s)
Ovinos/fisiología , Piel/irrigación sanguínea , Animales , Capilares/diagnóstico por imagen , Capilares/fisiología , Miembro Posterior , Masculino , Microesferas , Orquiectomía , Cintigrafía , Flujo Sanguíneo Regional , Radioisótopos de Xenón
15.
J Appl Physiol (1985) ; 65(1): 165-72, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3403461

RESUMEN

To determine whether the reported absence of fever in full-term-pregnant ewes might be associated with shifts of regional blood flows from thermogenic tissues to placenta during this critical period, fevers were induced twice by injections of Escherichia coli lipopolysaccharide (LPS, 0.25 microgram/kg iv) into each of six Merino ewes from 8 to 1 days prepartum, and their regional blood flow distribution was measured with radioactive, 15-microns-diam microspheres before and during the rise in fever (when their rectal temperature had risen approximately 0.4 degree C). Unexpectedly, fever always developed, rising to heights not significantly different at any time before parturition [4-8 days prepartum = 0.81 +/- 0.23 degree C (SE); 1-3 days prepartum = 0.75 +/- 0.17 degree C) and similar to those in three wethers treated similarly (0.90 +/- 0.10 degree C). Generally, during rising fever, blood flow in the ewes shifted away from heat loss tissues (e.g., skin, nose) to heat production tissues (e.g., shivering muscle, fat) and cardiac output increased; blood flow through redistribution organs (e.g., splanchnic bed) decreased. The reverse occurred during defervescence. Utero-placental blood flow remained high in the febrile ewes. These regional blood flow distributions during febrigenesis and lysis are essentially the same as those during exposures to ambient cold and heat, respectively. Some differences in the responses of cardiac output and its redistribution, however, were apparent between wethers and pregnant ewes. We conclude that 1) the previously reported "absence of fever in the full-term-pregnant sheep" should not be regarded as a general phenomenon and 2) full-term-pregnant sheep support fever production without sacrificing placental blood flow.


Asunto(s)
Fiebre/fisiopatología , Animales , Temperatura Corporal , Regulación de la Temperatura Corporal , Femenino , Hemodinámica , Hierro/sangre , Embarazo , Flujo Sanguíneo Regional , Ovinos
16.
J Appl Physiol (1985) ; 60(5): 1759-64, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3710991

RESUMEN

Radioactive microspheres were used to measure cardiac output and blood flow to most major tissues, including those in the pregnant uterus, in late-pregnant ewes at rest and during treadmill exercise (approximately 3-fold increase in metabolic rate for 30 min) in thermoneutral (TN) (dry bulb temperature (Tdb) = 13 degrees C, wet bulb temperature (Twb) = 10 degrees C) and mildly hot (MH) (Tdb = 40 degrees C, Twb = 27 degrees C) environments. Exercise caused major increases in blood flow to respiratory muscles, nonrespiratory limb muscles, and adipose tissue, and flow was decreased to some gastrointestinal tissues, spleen, pancreas, and to placental and nonplacental tissues in the pregnant uterus. Heat exposure had relatively little effect on these exercise-induced changes, except that flow was further increased in the respiratory muscles. Results are compared with those of a similar study on nonpregnant sheep in which changes in muscle, skin, and visceral flows during exercise were attenuated by heat exposure. It is suggested that redistribution of blood flow from the pregnant uterus, which in resting ewes took 22% of cardiac output, is a significant buffer against the potentially deleterious effects of combined exercise and heat stress on blood flow to exercising muscles and thermoregulatory tissues.


Asunto(s)
Hemodinámica , Calor/efectos adversos , Esfuerzo Físico , Animales , Regulación de la Temperatura Corporal , Gasto Cardíaco , Sistema Cardiovascular/fisiopatología , Femenino , Músculos/irrigación sanguínea , Embarazo , Flujo Sanguíneo Regional , Sistema Respiratorio/fisiopatología , Ovinos , Estrés Fisiológico/fisiopatología , Útero/irrigación sanguínea
17.
J Neurosurg ; 54(5): 620-6, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-7229700

RESUMEN

Blood flow for the whole spinal cord (SCBF), central cord (largely gray matter), and peripheral cord (largely white matter) has been measured at all segmental levels using radioactive microspheres in conscious sheep. Whole SCBF was greatest in the lower cervical and lumbar enlargements and least in the upper cervical and thoracic regions. This was attributable partly to regional variations in gray-matter blood flow but principally to regional variations in the proportion of gray and white matter present. Whole SCBF for the total cord was 14.5 +/- 0.8 ml/100 gm/min, central cord flow was 40.6 +/- 3.5 ml/100 gm/min, and peripheral cord flow was 9.7 +/- 1.9 ml/100 gm/min. Blood flow was not affected by sodium pentobarbital provided the level of anesthesia, arterial pressure, and blood gases was carefully regulated. Laminectomy usually resulted in a marked increase in central cord blood flow at the site of cord exposure, lasting about 90 minutes; this increase was not necessarily reflected in whole SCBF because of the absence of any change in blood flow in the relatively large proportion of peripheral cord. This effect of laminectomy could adversely influence results obtained from studies using invasive techniques to measure SCBF.


Asunto(s)
Anestesia Intravenosa , Laminectomía , Médula Espinal/irrigación sanguínea , Animales , Estado de Conciencia , Femenino , Flujo Sanguíneo Regional , Ovinos , Temperatura
18.
Spine (Phila Pa 1976) ; 9(7): 676-80, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6505835

RESUMEN

The effect of experimental trauma on the blood flow in the central (essentially gray matter) and peripheral (essentially white matter) regions of the sheep's spinal cord was studied using a radioactive microsphere technique. In seven out of eight animals, a progressive fall in blood flow occurred in both the peripheral and central regions of the cord within 2 hours following injury and remained reduced over the period of recording (up to 12 hours). Changes in local vascular resistance indicated that in approximately 60% of our animals, changes in arterial pressure alone contributed highly significantly to the decreased spinal blood flow. There remains the possibility that early therapeutic intervention could sustain neuronal function where local blood flow would otherwise be inadequate in the damaged spinal cord.


Asunto(s)
Traumatismos de la Médula Espinal/fisiopatología , Médula Espinal/irrigación sanguínea , Animales , Presión Sanguínea , Contusiones/fisiopatología , Femenino , Microesferas , Radioisótopos , Flujo Sanguíneo Regional , Ovinos , Factores de Tiempo , Resistencia Vascular
19.
Ann Dyslexia ; 44(1): 147-64, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24234050

RESUMEN

There is a growing body of evidence that children with dyslexia have problems not just in reading but in a range of skills including several unrelated to reading. In an attempt to compare the severity and incidence of deficits across these varied domains, children with dyslexia (mean ages 8, 12, and 16 years), and control groups of normally achieving children matched for IQ and for age or reading age, were tested on a range of primitive (basic) skills. The children with dyslexia performed significantly worse than the same-age controls on most tasks, and significantly worse even than the reading-age controls on phoneme segmentation, picture naming speed, word tachistoscopic word recognition, speeded bead threading and some balance tasks. The overall performance of the children with dyslexia is interpreted as showing less complete automatization than normal.

20.
Ann Dyslexia ; 46(1): 259-83, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24234275

RESUMEN

It is now thought that the cerebellum is involved in the acquisition of "language dexterity" in addition to its established role in motor skill acquisition and execution. Mild cerebellar impairment, therefore, provides a possible explanation of a range of problems shown by children with dyslexia. The authors have established suggestive evidence in support of this hypothesis in tests of balance and of time estimation. In a further test of the hypothesis, a battery of clinical tests for cerebellar impairment, including tests of muscle tone and of coordination, was administered to matched groups of children with dyslexia and control children aged 10, 14, and 18 years (55 subjects in all). The children with dyslexia showed highly significant impairments on all the cerebellar tests, and significant impairment compared even with reading age controls on 11 of the 14 tasks. Deficits on the majority of tests were among the largest found in our research program. The findings, therefore, provide further intriguing evidence of cerebellar impairment in dyslexia. We speculate that the well-established phonological deficits in dyslexia may arise initially from inefficient articulatory control attributable to cerebellar impairment.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA