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1.
Disabil Rehabil ; : 1-9, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950406

RESUMEN

PURPOSE: This focus group study aimed to explore experiences and perceptions on post-stroke fatigue guidance in Dutch rehabilitation and follow-up care among people/patients with stroke and health professionals. METHODS: Ten persons with stroke and twelve health professionals with different professions within stroke rehabilitation or follow-up care in the Netherlands were purposively sampled and included. Eight online focus group interviews were conducted. We analysed the data using reflexive thematic analysis. RESULTS: Three themes were identified. Guidance in fatigue management did not always match the needs of people/patients with stroke. Professionals were positive about the provided fatigue guidance (e.g. advice on activity pacing), but found it could be better tailored to the situation of people/patients with stroke. Professionals believe the right time for post-stroke fatigue guidance is when people/patients with stroke are motivated to change physical activity behaviour to manage fatigue - mostly several months after stroke - while people/patients with stroke preferred information on post-stroke fatigue well before discharge. Follow-up care and suggestions for improvement described that follow-up support after rehabilitation by a stroke coach is not implemented nationwide, while people/patients with stroke and professionals expressed a need for it. CONCLUSIONS: The study findings will help guide improvement of fatigue guidance in stroke rehabilitation programmes and stroke follow-up care aiming to improve physical activity, functioning, participation, and health.


We recommend fatigue guidance, including peer support, to be accessible to all people after stroke and for health professionals to pay attention to acceptance of the stroke.To improve fatigue guidance, we suggest providing information on post-stroke fatigue to people after stroke and their relatives well before discharge from stroke rehabilitation.Tailored advice on activity pacing during and after stroke rehabilitation is important to fill the current unmet need of people after stroke to manage fatigue and to gradually improve participation, physical activity behaviour and health.We recommend to health professionals working in stroke rehabilitation to tailor the rehabilitation schedule to their patients' energy level and perception of fatigue levels.

2.
Sci Total Environ ; 763: 143052, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33189383

RESUMEN

Seagrasses are important habitats providing many ecological services. Most species have broad distributions with maximum dispersal distances of 100's of kms, however there is limited understanding of dispersal distances of colonising species like Halodule uninervis. It commonly grows in disturbed environments and could disperse to other meadows via clonal fragments. Effective conservation management requires greater understanding of genetic structure, dispersal barriers, and connectivity timescales to predict recovery following disturbance. Despite fragment viability of up to 28 days in a congenera, this theory remains untested in situ. Using 80 neutral single nucleotide polymorphisms, we investigated genetic diversity, gene flow patterns and structure among 15 populations of H. uninervis along 2000 km of Western Australian coastline. These data were combined with a multi-generational oceanographic dispersal model and a barrier dispersal analysis to identify dispersal barriers and determine which fragment dispersal duration (FDD) and timescale over which stepping-stone connectivity occurred, best matched the observed genetic structure. The 2-7 day FDD best matched the genetic structure with 4-12 clusters, with barriers to dispersal that persisted for up to 100 years. Modelling suggested greater fragmentation of metapopulations towards the southern edge of the species distribution, but genetic diversity did not decline. Several long-term boundaries were identified even with fragment viability of up to 28 days. This suggests H. uninervis dispersal is spatially limited by factors like oceanographic features and habitat continuity which may limit dispersal of this species. This study reiterates that potential dispersal does not equal realised dispersal, and management scales of 10's of kilometers are required to maintain existing meadows. Recruitment from distances further than this scale are unlikely to aid recovery after extreme disturbance events, particularly towards the range edge of H. uninervis distribution.


Asunto(s)
Alismatales , Flujo Génico , Australia , Ecosistema , Variación Genética
4.
Soft Matter ; 11(19): 3913-9, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25869967

RESUMEN

Patchy colloidal particles are promising candidates for building blocks in directed self-assembly. To be successful the surface patterns need to be simple enough to be synthesized, while feature-rich enough to cause the colloidal particles to self-assemble into desired structures. Achieving this is a challenge for traditional synthesis methods. Recently it has been suggested that surface patterns themselves can be made to self-assemble. In this paper we present a design path for the hierarchical targeted self-assembly of patchy colloidal particles based on self-assembling surface patterns. At the level of the surface structure, we use a predictive method utilizing the universality of stripes and spots, coupled with stoichiometric constraints, to cause highly specific and functional patterns to self-assemble on spherical surfaces. We use a minimalistic model of an alkanethiol on gold as a demonstration, showing that even with limited control over the interaction between surface constituents we can obtain patterns that cause the colloidal particles themselves to self-assemble into various complex geometric structures, such as strings, membranes, cubic aggregates and colloidosomes, as well as various crystalline patterns.

5.
J Chem Phys ; 139(2): 024107, 2013 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-23862929

RESUMEN

We present a method that systematically simplifies isotropic interactions designed for targeted self-assembly. The uncertainty principle is used to show that an optimal simplification is achieved by a combination of heat kernel smoothing and Gaussian screening of the interaction potential in real and reciprocal space. We use this method to analytically design isotropic interactions for self-assembly of complex lattices and of materials with functional properties. The derived interactions are simple enough to narrow the gap between theory and experimental implementation of theory based designed self-assembling materials.

6.
Phys Rev Lett ; 108(16): 165502, 2012 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-22680733

RESUMEN

We show that chiral symmetry can be broken spontaneously in one-component systems with isotropic interactions, i.e., many-particle systems having maximal a priori symmetry. This is achieved by designing isotropic potentials that lead to self-assembly of chiral surfaces. We demonstrate the principle on a simple chiral lattice and on a more complex lattice with chiral supercells. In addition, we show that the complex lattice has interesting melting behavior with multiple morphologically distinct phases that we argue can be qualitatively predicted from the design of the interaction.


Asunto(s)
Modelos Biológicos , Modelos Químicos , Estereoisomerismo
7.
Phys Rev Lett ; 107(8): 085501, 2011 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-21929172

RESUMEN

We present results from particle simulations with isotropic medium range interactions in two dimensions. At low temperature novel types of aggregated structures appear. We show that these structures can be explained by spontaneous symmetry breaking in analytic solutions to an adaptation of the spherical spin model. We predict the critical particle number where the symmetry breaking occurs and show that the resulting phase diagram agrees well with results from particle simulations.

8.
Phys Rev Lett ; 107(8): 085503, 2011 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-21929174

RESUMEN

We present a direct method for solving the inverse problem of designing isotropic potentials that cause self-assembly into target lattices. Each potential is constructed by matching its energy spectrum to the reciprocal representation of the lattice to guarantee that the desired structure is a ground state. We use the method to self-assemble complex lattices not previously achieved with isotropic potentials, such as a snub square tiling and the kagome lattice. The latter is especially interesting because it provides the crucial geometric frustration in several proposed spin liquids.

9.
J Bone Joint Surg Br ; 92(10): 1381-4, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20884975

RESUMEN

We investigated the role of a functional brace worn for four months in the treatment of patients with an acute isolated tear of the posterior cruciate ligament to determine whether reduction of the posterior tibial translation during the healing period would give an improved final position of the tibia. The initial and follow-up stability was tested by Rolimeter arthrometry and radiography. The clinical outcome was evaluated using the Lysholm score, the Tegner score and the International Knee Documentation Committee scoring system at follow-up at one and two years. In all, 21 patients were studied, 21 of whom had completed one-year and 17 a two-year follow-up. The initial mean posterior sag (Rolimeter measurement) of 7.1 mm (5 to 10) was significantly reduced after 12 months to a mean of 2.3 mm (0 to 6, p < 0.001) and to a mean of 3.2 mm (2 to 7, p = 0.001) after 24 months. Radiological measurement gave similar results. The mean pre-injury Lysholm score was normal at 98 (95 to 100). At follow-up, a slight decrease in the mean values was observed to 94.0 (79 to 100, p = 0.001) at one year and 94.0 (88 to 100, p = 0.027, at two years). We concluded that the posterior cruciate ligament has an intrinsic healing capacity and, if the posteriorly translated tibia is reduced to a physiological position, it can heal with less attentuation. The applied treatment produces a good to excellent functional result.


Asunto(s)
Tirantes , Traumatismos de la Rodilla/terapia , Ligamento Cruzado Posterior/lesiones , Enfermedad Aguda , Adolescente , Adulto , Artrometría Articular/métodos , Tirantes/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Traumatismos de la Rodilla/fisiopatología , Articulación de la Rodilla/fisiopatología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recuperación de la Función , Resultado del Tratamiento , Adulto Joven
10.
Phys Rev Lett ; 105(13): 137203, 2010 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-21230804

RESUMEN

We present a method for predicting the low-temperature behavior of spherical and Ising spin models with isotropic potentials. For the spherical model the characteristic length scales of the ground states are exactly determined but the morphology is shown to be degenerate with checkerboard patterns, stripes and more complex morphologies having identical energy. For the Ising models we show that the discretization breaks the degeneracy causing striped morphologies to be energetically favored and therefore they arise universally as ground states to potentials whose Hankel transforms have nontrivial minima.

11.
Orthopade ; 33(2): 143-52, 2004 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-14872305

RESUMEN

Closing wedge high tibial osteotomy is an efficient method for the treatment of medial osteoarthritis of the knee. Prerequisites of successful surgery are proper indication and planning as well as the understanding of biomechanics and pathophysiology. The technique of osteotomy to choose (opening or closing wedge) depends on the type of malalignment and on additional pathologies. The surgical technique demands high precision to realize the planned correction and to avoid complications. Implants with angular stability provide advantages compared to traditional implants. Correct indication and surgical technique results in a desirable follow-up, which often lasts for at least 10 years. The effect on the prognosis of the young patient with cartilage damage is still unclear.


Asunto(s)
Articulación de la Rodilla/cirugía , Osteoartritis/cirugía , Osteotomía/métodos , Tibia/cirugía , Desviación Ósea/diagnóstico por imagen , Desviación Ósea/cirugía , Placas Óseas , Tornillos Óseos , Femenino , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Persona de Mediana Edad , Osteoartritis/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Radiografía Panorámica/métodos , Resultado del Tratamiento , Interfaz Usuario-Computador
13.
Lab Anim Sci ; 47(6): 624-31, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9433699

RESUMEN

Cardiopulmonary and acid-base variables recorded during long-term balanced anesthesia lasting between 12.5 and 16.9 h were evaluated retrospectively in 15 healthy foxhounds that underwent experimental bulla osteotomy with implantation of hearing aids. After premedication with propionylpromazine (0.11 +/- 0.02 mg/kg of body weight) and L-methadone (0.71 +/- 0.06 mg/kg) intravenously (i.v.) and induction with pentobarbital sodium (6.02 +/- 0.83 mg/kg i.v.), anesthesia was maintained with halothane (end-tidal concentration; ETHAL: 0.4 to 1.5%) in nitrous oxide (2 L/min) and oxygen (1 L/min). Because of positional changes from sternal to right lateral recumbency after presurgical brain stem electric response audiometry and differences in duration of surgery, data obtained between 4 (baseline) and 14 h after induction of anesthesia were analyzed. Arterial (PaO2) and alveolar (PAO2) O2 tensions, arterial-to-alveolar O2 tension ratio (PaO2/PAO2), and arterial O2 content (CaO2) remained relatively stable throughout anesthesia. Arterial carbon dioxide tension (PaCO2) was significantly increased above baseline (39, 33 to 46 mm Hg [median, range]) between 7 (39.8, 36.5 to 48.9 mm Hg) and 9 (42, 37.5 to 49.5 mm Hg) h after induction. Because changes in PaCO2 were accompanied by significant increases in body temperature from baseline (36.3, 34.6 to 37.4 degrees C) between 8 (37.1, 35 to 38 degrees C) and 11 (37.6, 35.3 to 38.1 degrees C) h after anesthesia induction as well as by slight increases in arterial blood pressure, the PaCO2 increase may have been caused by increase in metabolic CO2 production and enhanced drainage of CO2 from the tissues into systemic circulation. Furthermore, mild metabolic acidosis (pHa: 7.31, 7.26 to 7.38; HCO3-: 18.9, 16.7 to 21.8 mEq/L; base deficit [BD]: -6.3, -8.5 to -3.4 mEq/L) already existed at 4 h after induction and was related in part to tissue hypoperfusion. Small increases in pHa during the course of anesthesia were accompanied by significant increases in HCO3- concentration and significant decreases in BD between 5 and 10 h after induction. Minor circumscribed swelling of the dependent triceps or masseter muscle was noticed on the first postoperative day in two dogs, and marked tissue swelling with hematoma formation at the medial side of one hind limb was noticed in a third dog. All dogs recovered completely and were submitted to follow-up studies. The anesthetic protocol and extent of monitoring used were adequate to provide safe long-term anesthesia for an experimental surgical procedure with a 100% survival rate and uneventful recovery in most of the dogs.


Asunto(s)
Equilibrio Ácido-Base/fisiología , Anestesia por Inhalación/veterinaria , Fenómenos Fisiológicos Cardiovasculares , Perros/fisiología , Perros/cirugía , Fenómenos Fisiológicos Respiratorios , Cirugía Veterinaria/métodos , Anestesia por Inhalación/métodos , Anestésicos por Inhalación , Animales , Presión Sanguínea/fisiología , Temperatura Corporal/fisiología , Femenino , Halotano , Frecuencia Cardíaca/fisiología , Concentración de Iones de Hidrógeno , Masculino , Osteotomía/métodos , Osteotomía/veterinaria , Estudios Retrospectivos , Volumen de Ventilación Pulmonar/fisiología , Factores de Tiempo
14.
Hosp Mater Manage Q ; 15(4): 12-22, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-10134147

RESUMEN

Manufacturing companies need to use the best and most applicable parts of MRP II and JIT to run their businesses effectively. MRP II provides the methodology to plan and control the total resources of the company and focuses on the processes that add value to their customers' products. It is the cornerstone of total quality management, as it reduces the variability and costly activities in the communication and subsequent execution of the required steps from customer order to shipment. JIT focuses on simplifying the total business operation and execution of business processes. MRP II and JIT are the foundations for successful manufacturing businesses.


Asunto(s)
Comercio/organización & administración , Equipos y Suministros , Sistemas de Información Administrativa , Administración de Línea de Producción/normas , Gestión de la Calidad Total , Técnicas de Planificación , Administración de Línea de Producción/métodos , Evaluación de Programas y Proyectos de Salud , Tecnología , Estados Unidos
15.
Hum Genet ; 90(1-2): 151-4, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1385294

RESUMEN

Four hundred fifty sperm complements from eight controls were analyzed. A conservative estimate of aneuploidy was 1.8% with a hyperhaploid rate of 0.9% (4/450). The overall frequency of structural aberrations was 8.9% (40/450). The proportion of X-bearing (47.5%) and Y-bearing (52.5%) sperm did not differ significantly. Sperm complements were analyzed from a cancer patient 9 months after polychemotherapy (n = 63) and from a patient being treated with Imurek (azathioprine) (n = 30). There was no significant increase in the incidence of numerical and structural chromosome aberrations in the sperm of either patient. The percentages of X-bearing and Y-bearing sperm were not significantly different from the expected 50%.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Azatioprina/efectos adversos , Aberraciones Cromosómicas , Espermatozoides/efectos de los fármacos , Adulto , Bleomicina/administración & dosificación , Bleomicina/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Quimioterapia Combinada , Disgerminoma/tratamiento farmacológico , Hepatitis Crónica/tratamiento farmacológico , Humanos , Masculino , Prednisona/uso terapéutico , Vindesina/administración & dosificación , Vindesina/efectos adversos
16.
J Appl Physiol (1985) ; 72(2): 677-85, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1559948

RESUMEN

Mechanisms underlying failure of autoresuscitation from hypoxic apnea were investigated. Failure was induced by repeated exposure to hypoxia. The influence of maturation was studied in adults, weanlings, and 10- and 5-day-old mice. Mice successful at autoresuscitation (BALB/c) as well as those prone to autoresuscitation failure (SWR weanlings) were studied. Hypoxic apnea was induced with 97% N2-3% CO2, and 21% O2 was given at its onset; electrocardiogram and ventilation were recorded. Hypoxic exposure was repeated if autoresuscitation (recovery of eupnea) occurred. Autoresuscitation failure (death) was induced in all mice. Young BALB/c mice tolerated more trials than older mice. SWR weanlings frequently failed to autoresuscitate on the initial exposure and tolerated fewer repeat trials overall than age-matched BALB/c mice. Induced autoresuscitation failure in all mice appeared to be unrelated to gasping regulation, because both gasp number and amplitude were similar during the failed trial and the previous successful trial. In most mice, failure was associated with absent recovery of heart rate during gasping. In BALB/c mice in particular, this persistent bradycardia was usually due to heart block, which occurred in 95% of failed trials. In addition, heart block occurred with increasing frequency on later successful trials, but conversion to sinus rhythm always preceded successful autoresuscitation. Heart block was also frequent in SWR mice and had similar consequences. BALB/c mice exposed to continuous anoxia survived longer than SWR mice, indicating increased endurance of components of the autoresuscitation mechanism not directly related to the ventilatory function of gasping (e.g., cardiovascular components).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Apnea/fisiopatología , Respiración/fisiología , Animales , Apnea/complicaciones , Modelos Animales de Enfermedad , Bloqueo Cardíaco/complicaciones , Homeostasis/fisiología , Hipoxia/complicaciones , Hipoxia/fisiopatología , Ratones , Ratones Endogámicos BALB C
17.
J Appl Physiol (1985) ; 71(3): 1098-105, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1757305

RESUMEN

The mechanism of failure of autoresuscitation from hypoxic apnea in 17- to 23-day-old (weanling) Swiss Webster related/J mice was investigated by recording electrocardiogram (ECG) and ventilation in adult, weanling, and 11-day-old mice. Hypoxic apnea was induced with 97% N2-3% CO2. O2 (21% or 50% O2) or 97% N2-3% CO2 was given at the onset of apnea. The ECG showed no arrhythmias predictive of failure of autoresuscitation. The first indication of failure was a progressive fall in gasp volume ("run down"). This pattern also occurred in animals given continuous 97% N2-3% CO2 and was significantly different from that in mice that survived. Gasping duration in 97% N2 was longer in weanlings than adults but shorter than in 11 day olds. Respiratory and heart rate recovery were more rapid in adults than in weanlings. Although recovery in high O2 was more rapid, the survival rate was not increased. The lack of effect of high O2 on survival and the virtually identical pattern of gasping in mice dying in 97% N2 and air leads us to conclude that in mice that fail to autoresuscitate little or no O2 reaches the medullary respiratory centers. We speculate that this may be due to increased vulnerability of cardiac muscle to anoxia in 17- to 23-day-old mice, resulting in early and severe heart failure.


Asunto(s)
Apnea/fisiopatología , Hipoxia/fisiopatología , Envejecimiento/fisiología , Obstrucción de las Vías Aéreas/fisiopatología , Animales , Electrocardiografía , Frecuencia Cardíaca/fisiología , Ratones , Ratones Endogámicos , Nitrógeno/metabolismo , Oxígeno/administración & dosificación , Pletismografía , Centro Respiratorio/fisiopatología , Tráquea/fisiopatología
18.
Respir Physiol ; 84(3): 337-49, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1925112

RESUMEN

The effect of pentobarbital anaesthesia on spontaneous recovery from hypoxic apnoea (autoresuscitation) was investigated in SWR/J mice. Experiments were performed in 17 to 23 day old animals, in which the mechanism often fails, and in adults, in which it is usually successful. Mice, matched for age and weight, were injected with pentobarbital (62.5 mg/kg) or saline. Hypoxic apnoea was induced with 97% N2-3% CO2 and air given at its onset. To determine whether the effect of pentobarbital depended on hypothermia, we performed experiments in 17-23-day-olds with and without maintenance of body temperature. In the 'hypothermic' experiments one of 27 mice given pentobarbital died, compared with 10 of 22 controls (P less than 0.005). In the 'isothermic experiments', none of 15 mice given pentobarbital died, compared to 7 of 13 controls (P less than 0.005). All adults in both groups survived. Pentobarbital had a different effect on eupnoea and gasping: resting ventilation was depressed but gasp ventilation increased, and the duty cycle of gasps but not eupnoeic breaths was altered. Pentobarbital may facilitate autoresuscitation because gasping is unimpaired but oxygen consumption and lactate production are reduced, allowing cardiac function and cerebral survival until PO2 is restored.


Asunto(s)
Apnea/fisiopatología , Hipoxia/fisiopatología , Pentobarbital/farmacología , Animales , Apnea/mortalidad , Temperatura Corporal , Hipoxia/mortalidad , Cinética , Ratones , Presión Esfenoidal Pulmonar , Respiración/efectos de los fármacos
19.
J Cardiothorac Anesth ; 4(5): 564-70, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1720336

RESUMEN

Acute plasmapheresis (APP) is an additional tool for blood conservation during cardiac surgery. In a randomized study of 60 aortocoronary bypass patients undergoing APP, the influence of replacement of the withdrawn autologous plasma (10 mL/kg) by either colloids (low molecular weight hydroxyethyl starch solution [6% HES 200/0.5]) or crystalloids (Ringer's solution) was investigated. APP was performed by means of a centrifugation technique producing platelet-poor plasma. During and after cardiopulmonary bypass (CPB), either a cell saver (CS) or a hemofiltration (HF) device was also used for blood concentration. Almost three times as much crystalloid as HES solution was necessary for replacement of autologous plasma. Fluid balance during CPB was significantly more positive in the crystalloid patients, particularly when a CS was used. Blood loss was highest in the crystalloid patients in whom a CS was used in addition to APP, and these were the only patients who needed packed red cells. The platelet count, AT-III and fibrinogen plasma concentrations, colloid osmotic pressure, albumin, and total protein were significantly less compromised in the patients with colloid volume replacement. These parameters were closest to control values in patients receiving colloid replacement and HF. It is concluded that colloid is preferred for replacement of autologous plasma withdrawn by APP, and HF is superior to the CS when the combined technique for blood conservation is used.


Asunto(s)
Puente de Arteria Coronaria , Derivados de Hidroxietil Almidón/administración & dosificación , Soluciones Isotónicas/administración & dosificación , Plasmaféresis , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Solución de Ringer
20.
Pediatr Res ; 28(2): 87-93, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2395608

RESUMEN

The maturation of the process of spontaneous recovery from hypoxic apnea by gasping (autoresuscitation) was characterized in adult, weanling (18-22 d), and infant (5 and 10 d) BALB/c mice. ECG and respiration were recorded and hypoxic apnea was induced with 97% N2-3% CO2. Administration of 21% O2 at onset of hypoxic apnea resulted in successful autoresuscitation in all 63 animals tested. In all mice, three sequential stages occurred: 1) gasping with marked bradycardia, 2) rapid increase in heart rate (cardiac resuscitation), and 3) increase in respiratory rate (respiratory resuscitation). Despite these similar stages, marked maturational differences were apparent. The times to cardiac and respiratory resuscitation were longer in the pups than in the older mice, whereas the gasp frequency before cardiac resuscitation was lower in the infants. Resuscitation time correlated with gasp interval (1/gasp frequency). In addition, the initial bradycardia at onset of gasping was more pronounced in the pups. A 30- or 60-s delay in oxygen administration after onset of hypoxic apnea caused a marked decrease in the adults' ability to autoresuscitate, without affecting that of the pups. A comparison of gasp frequency in 21% O2 versus 97% N2-3% CO2 showed that the presence of oxygen increased gasp frequency in the pups, but had no effect on gasp frequency in the weanlings or adults. We conclude that autoresuscitation is equally effective in both infant and adult BALB/c mice but only when oxygen is available before the onset of hypoxic gasping.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Apnea/fisiopatología , Sistema Cardiovascular/fisiopatología , Hipoxia/fisiopatología , Sistema Respiratorio/fisiopatología , Envejecimiento/fisiología , Animales , Sistema Cardiovascular/crecimiento & desarrollo , Frecuencia Cardíaca/fisiología , Ratones , Ratones Endogámicos BALB C , Oxígeno , Respiración/fisiología , Sistema Respiratorio/crecimiento & desarrollo
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