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1.
J Environ Manage ; 345: 118582, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37540979

RESUMEN

Globally, agriculture has had a significant and often detrimental impact on soil. The continued capacity of soil to function as a living ecosystem that sustains microbes, plants, and animals (including humans), its metaphorical health, is of vital importance across geographic scales. Healthy soil underpins food production and ecosystem resilience against a changing climate. This paper focuses on assessing soil health, an area of increasing interest for farming communities, researchers, industry and policy-makers. Without accessible and reliable soil assessment, any management and interventions to improve soil health are likely to be sub-optimal. Here we explore available soil health assessments (SHAs) that may be feasible for farmers of varying income levels and suitable for broad geographic application. Whilst there is a range of existing approaches to SHA, we find that no one framework currently meets these broad aims. Firstly, reliance on expensive and logistically complex laboratory methods reduces viability and accessibility for many farmers. Secondly, lack of defined indicator baselines and associated thresholds or gradients for soil health prevents the assessment of soil measurements against achieving optima for a given set of local soil-climate conditions. Since soils vary greatly, these baselines and thresholds must be defined considering the local biogeographic context; it is inappropriate to simply transfer calibrated information between contexts. These shortcomings demand progress towards a feasible, globally applicable and context-relevant SHA framework. The most feasible SHAs we identified were developed locally in conjunction with farmers, who have been repeatedly found to assess the health of their soils accurately, often using relatively simple, observable indications. To progress, we propose assessment of which indicators add information to a SHA in local contexts, with a focus on sufficiency, to reduce data burden. Provision of a standardised protocol for measurement and sampling that considers the reliability and accuracy of different methods would also be extremely valuable. For greatest impact, future work should be taken forward through a cross-industry collaborative approach involving researchers, businesses, policy makers, and, above all, farmers, who are both experts and users.


Asunto(s)
Agricultores , Suelo , Animales , Humanos , Ecosistema , Reproducibilidad de los Resultados , Agricultura
2.
Clin Pharmacol Ther ; 45(3): 305-11, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2920505

RESUMEN

The effects of administration of Theo-Dur Sprinkle in the fasting state (phase A), 10 minutes before food (phase B), and immediately after food (phase C) were investigated in 12 children with asthma aged 5 to 9 years at steady state. The AUC during the dosing interval was significantly reduced in phases B and C compared with phase A, and bioavailability relative to the fasting state was reduced to 77% +/- 15% (range 61% to 104%) in phase B and 70% +/- 16% (range 40% to 103%) in phase C. The average plasma theophylline concentration during the dosing interval and Cmax were also significantly reduced in phases B and C compared with phase A. The morning predose plasma theophylline concentration in phase B was 22% lower than the predose concentration with Theo-Dur tablets taken 10 minutes before breakfast. The diurnal variation in predose plasma theophylline concentrations was increased from 28% in phase A to 63% in phase C. There was no significant difference in any parameter between administration 10 minutes before food and immediately after food.


Asunto(s)
Alimentos , Teofilina/farmacocinética , Asma/tratamiento farmacológico , Disponibilidad Biológica , Niño , Preescolar , Ritmo Circadiano , Preparaciones de Acción Retardada , Ayuno , Femenino , Humanos , Masculino , Distribución Aleatoria , Teofilina/administración & dosificación , Teofilina/uso terapéutico , Factores de Tiempo
3.
J Clin Pathol ; 25(9): 789-92, 1972 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-5086222

RESUMEN

Serum levels of albumin, transferrin, alpha(2)-macroglobulin, beta(1)C/beta(1)A, IgA, IgG, and IgM have been determined in 73 patients with primary biliary cirrhosis and in age- and sex-matched controls. A highly significant fall in albumin was demonstrated, and there were highly significant increases in alpha(2)-macroglobulin and all three immunoglobulin levels. Transferrin and beta(1)/Cbeta(1)A levels were unchanged. No significant correlations were found between the titre of antimitochondrial antibody, the duration of symptoms, and any of the serum proteins estimated. A highly significant positive correlation was present between serum albumin and transferrin levels in both patient and control groups.


Asunto(s)
Proteínas Sanguíneas/análisis , Cirrosis Hepática Biliar/sangre , Adulto , Anciano , Autoanticuerpos/análisis , Electroforesis de las Proteínas Sanguíneas , Femenino , Humanos , Inmunoglobulina A/análisis , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Cirrosis Hepática Biliar/inmunología , Macroglobulinas/análisis , Masculino , Persona de Mediana Edad , Mitocondrias/inmunología , Albúmina Sérica/análisis , Transferrina/análisis
4.
J Abnorm Child Psychol ; 7(2): 211-9, 1979 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-469114

RESUMEN

Two contigency systems, individual and group, were evaluated for their effects on children's behavior during small group meetings. Forty-eight children, ages 8 through 14, attended a 7-week residential camp program operated on a token economy system. Ratings of the campers' behavior were made by the counselors on a 5-point rating scale at the daily meetings. Each camper received both contingency programs, in counterbalanced order. Data were gathered during baseline, two feedback and two treatment phases. An analysis of variance for repeated measures was performed on the mean weekly camper scores. The two systems were equally effective in significantly increasing the amount of desirable behavior, and there was no effect on behavior due to feedback alone. The results are discussed in terms of advantages and disadvantages of each type of contingency system, with some suggestions made regarding areas of further investigation.


Asunto(s)
Terapia Conductista/métodos , Acampada , Trastornos de la Conducta Infantil/terapia , Psicoterapia de Grupo , Niño , Retroalimentación , Femenino , Humanos , Masculino , Tratamiento Domiciliario , Conducta Social , Régimen de Recompensa
5.
Drug Metabol Drug Interact ; 7(1): 53-86, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2699284

RESUMEN

The isolated perfused liver system is a versatile model for investigating the effects and mechanisms of action of hepatotoxins and the metabolism of endogenous and exogenous compounds. The interpretation of metabolic data and apparent toxic events is dependent upon the viability and reproducibility of the model. In this study, a new approach has been undertaken to assess the viability of isolated liver preparations. This has involved the continuous monitoring of multistage processes namely, the synthesis and secretion of radiolabelled proteins, glycoproteins and lipoproteins on the one hand and the uptake of macromolecules by receptor-mediated endocytosis on the other. The consistency of these complex integrated processes from one liver to another and in particular the steady-state rate of production of radiolabelled macromolecules over 6h perfusion periods suggests that this model can be used with confidence for metabolic/toxicological investigations. The selectivity of the responses to chemical challenge(s) shows that this system can be exploited for (a) screening potential hepatotoxins; (b) identifying areas of metabolism which are affected and (c) advancing basic knowledge of liver biochemistry.


Asunto(s)
Hígado/metabolismo , Perfusión/instrumentación , Toxicología/instrumentación , Animales , Técnicas In Vitro , Hígado/fisiología , Preparaciones Farmacéuticas/metabolismo
6.
Child Abuse Negl ; 16(5): 673-91, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1393727

RESUMEN

A typology of physically abusive parents was developed based upon personality characteristics measured by the 16-PF. Cluster analysis revealed five distinct patterns, accounting for 81 of 82 profiles submitted. Significant differences among the clusters were found on 14 of the 16 factors. The following types were described: (a) Shy, withdrawn, apprehensive, sober, and restrained; tending to have the least education, the greatest number of children. (b) Parents presenting as "normal" in personality features; tending to have relatively more education, fewer children. (c) Compulsive, bold, dominant, and assertive; tending to be highly manipulative in self-presentations, have high educational levels, and be older than other types. (d) Basically passive and submissive; tending to come from families where both parents are abusive. (e) Isolated, withdrawn, suspicious, tense, and apprehensive; tending to be more psychologically disturbed. Significance tests on external variables performed to validate the solution found differences among clusters in age, education, number of children, number of parents involved in abuse, 16-PF Faking Good and Faking Bad scores, and MMPI Scales L, F, K, 4, 5, 6, 7, and 0. Distinguishing personality features and demographic characteristics of the types are discussed with a focus upon possible treatment approaches for each type. Limitations of the study and suggestions for future research are addressed.


Asunto(s)
Maltrato a los Niños/psicología , Hijo de Padres Discapacitados/psicología , Padres/psicología , Inventario de Personalidad/estadística & datos numéricos , Adulto , Niño , Análisis por Conglomerados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Desarrollo de la Personalidad , Psicometría
7.
Adolescence ; 34(135): 621-33, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10658869

RESUMEN

This study examined gender differences in eating attitudes and behaviors in a sample of 471 undergraduate college students. The prevalence of symptomatology indicative of anorexia was determined using the Eating Attitudes Test (EAT-26). In addition, the family climate, parent-child dynamics, and self-concept of students with and without maladaptive eating attitudes and behaviors were compared, and the relationship between eating attitudes/behaviors and current psychological distress was examined. Anorexic symptomatology was found for 20% of the females and 10% of the males. In general, students without symptomatic attitudes and behaviors had a more positive self-concept and reported less psychological distress than did those with eating disturbances. The findings suggest that eating problems may be more prevalent among males than previously estimated.


Asunto(s)
Anorexia Nerviosa/psicología , Actitud Frente a la Salud , Conducta Alimentaria , Estudiantes/psicología , Adolescente , Adulto , Anorexia Nerviosa/diagnóstico , Femenino , Identidad de Género , Humanos , Masculino , Inventario de Personalidad
8.
Adolescence ; 28(109): 29-40, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8456614

RESUMEN

This study examined whether the structural intactness of the family and/or perceived family conflict was related to young adult adjustment as assessed by measures of ego identity status and psychological distress. The physical-wholeness model holds that family structure is the major variable affecting adjustment, while the psychological-wholeness model posits family conflict as the critical variable. In the present study, undergraduate college students (N = 285) were classified as belonging to an intact two-parent family or a nonintact family, and as coming from homes characterized by low, medium, or high levels of conflict. A statistically significant relationship between family conflict and adjustment was observed; there was no significant association between family structure and adjustment. Individuals from families perceived as being low or medium in level of conflict reported fewer psychiatric symptoms and demonstrated higher levels of ego identity than did those from families perceived as high in conflict. These findings support the psychological-wholeness model. It is suggested that future research be directed toward developing more refined measures of interpersonal conflict.


Asunto(s)
Adaptación Psicológica , Conflicto Psicológico , Familia/psicología , Desarrollo de la Personalidad , Medio Social , Estudiantes/psicología , Adolescente , Adulto , Escolaridad , Composición Familiar , Femenino , Humanos , Masculino , Determinación de la Personalidad
9.
Percept Mot Skills ; 64(2): 469-70, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3588192

RESUMEN

Mothers of 212 children aged 2 to 12 yr. responded to a problem checklist. Significantly more children reported as maltreated were said to have learning difficulties than comparison children; language delays and poor motor coordination were also noted. Such children would benefit from the formal assessment and remediation of problems in motor development.


Asunto(s)
Maltrato a los Niños/psicología , Discapacidades para el Aprendizaje/psicología , Desempeño Psicomotor , Niño , Desarrollo Infantil , Preescolar , Femenino , Humanos , Masculino , Relaciones Madre-Hijo
11.
J Clin Psychol ; 52(5): 535-41, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8877688

RESUMEN

The relation between childhood molestation and current adjustment, as measured by the Brief Symptom Inventory (BSI), was examined among women college students. Results suggest that the normative data available for the BSI are inappropriate for interpreting the performance of women college students and, particularly, students who have survived sexual abuse.


Asunto(s)
Abuso Sexual Infantil/psicología , Psicometría/normas , Índice de Severidad de la Enfermedad , Estudiantes/psicología , Sobrevivientes/psicología , Mujeres/psicología , Adolescente , Adulto , Femenino , Humanos , Muestreo , Rol del Enfermo , Estrés Psicológico/diagnóstico
12.
Am J Orthod Dentofacial Orthop ; 93(3): 201-5, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3422775

RESUMEN

By means of corrected tomography, the positions of the condyles in patients who had undergone four-premolar extraction treatment (20 edgewise and 7 Begg) were compared with the condylar positions of patients who had not yet received orthodontic treatment. No significant between-group differences in condylar position were noted. In addition, the relationship between bite depth and condylar position was examined and no significant correlation was found. Thus, as performed in this study, condylar position was unrelated to extraction treatment and to bite depth.


Asunto(s)
Diente Premolar/cirugía , Maloclusión/terapia , Cóndilo Mandibular/anatomía & histología , Extracción Seriada , Adolescente , Niño , Método Doble Ciego , Femenino , Humanos , Luxaciones Articulares/patología , Masculino , Maloclusión/patología , Articulación Temporomandibular/anatomía & histología , Articulación Temporomandibular/patología , Tomografía por Rayos X , Técnicas de Movimiento Dental
13.
Xenobiotica ; 26(12): 1273-82, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9004457

RESUMEN

1. Studies have been carried out to investigate the absorption of sumatriptan after intranasal administration to rats. The pharmacokinetics, metabolism and excretion of 14C-sumatriptan were compared following intranasal and intravenous dosing to male and female albino rats using an aqueous buffered formulation at pH 5.5. 2. Following intravenous administration sumatriptan was eliminated from plasma with a half-life of about 1.1 h. After intranasal administration there was rapid absorption of part of the dose and two peak plasma concentrations were observed, initially at 0.5 and then at 1.5-2 h. The elimination half-life after the second peak was estimated as being about 4 h. 3. Radioactivity was largely excreted in urine (up to 89% of dose in 168 h) after both intravenous and intranasal administration, with a faster rate of excretion after intravenous dosage (73% males, 64% females within 6 h) than after intranasal dosage (37% males, 40% females within 6 h). 4. 14C-sumatriptan was the major component in urine and in extracts of faeces after both intravenous and intranasal administration. The major metabolite excreted in urine and faeces was GR49336, the indole acetic acid analogue. 5. The results of this in vivo rat study suggest that absorption of the dose via the nasal mucosa is incomplete after intranasal administration and that there is a secondary absorption phase probably reflecting oral absorption of part of the dose. The bioavailability is estimated as about 30%, for the period 0-6 h.


Asunto(s)
Sumatriptán/administración & dosificación , Sumatriptán/farmacocinética , Absorción , Administración Intranasal , Animales , Radioisótopos de Carbono , Femenino , Semivida , Cinética , Masculino , Ratas , Ratas Sprague-Dawley
14.
Biochem J ; 277 ( Pt 3): 795-800, 1991 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-1651704

RESUMEN

Halothane or CCl4 was co-administered with the spin trap N-tert-butyl-alpha-(4-nitrophenyl)nitrone (PBN) to rats fitted with bile duct cannuli or to isolated perfused liver preparations. Rats maintained under halothane anaesthesia generated significant amounts of free radicals, and 5-9 nmol was excreted in bile over 1 h. No adducts were detected in urine or plasma. The hepatic origin of these free radicals was confirmed by studies on isolated perfused livers where the addition of halothane to the perfusate resulted in the biliary elimination of the same PBN-trapped radical adducts. Similarly, following CCl4 administration, the same radical species were eliminated in bile in the whole animal and the perfused liver preparation. In the perfused liver, over 3 h the total biliary elimination of radicals derived from halothane or CCl4 (administered at equimolar concentrations) was approximately the same (5-7 nmol); however, the elimination of halothane-derived radicals was more rapid over the first 1 h.


Asunto(s)
Halotano/metabolismo , Hígado/metabolismo , Óxidos de Nitrógeno/química , Animales , Bilis/metabolismo , Tetracloruro de Carbono/metabolismo , Intoxicación por Tetracloruro de Carbono/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Radicales Libres , Halotano/química , Nitrobencenos , Óxidos de Nitrógeno/metabolismo , Ratas , Ratas Endogámicas
15.
Biochem J ; 259(2): 537-43, 1989 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-2719664

RESUMEN

The metabolism of 14C- and 36Cl-labelled 1,6-dichloro-1,6-dideoxyfructose (DCF) was studied in the isolated perfused rat liver system. Dechlorination of DCF occurred in the liver and erythrocytes and was GSH-dependent. The GSH conjugate formed was identified by 13C and 1H n.m.r. as the 6-chlorofructos-1-yl-SG conjugate. It is proposed that the GS- anion attacks the low steady-state concentration of the reactive keto form of DCF and that the conjugate formed cyclizes to the dominant beta-anomer. 6-Chlorofructos-1-yl-SG conjugate of hepatic origin is excreted into bile, whereas that produced in erythrocytes does not enter the liver.


Asunto(s)
Desoxiazúcares/metabolismo , Fructosa/análogos & derivados , Glutatión/metabolismo , Animales , Bilis/metabolismo , Fructosa/metabolismo , Glutatión/análogos & derivados , Técnicas In Vitro , Hígado/metabolismo , Espectroscopía de Resonancia Magnética , Perfusión , Ratas , Ratas Endogámicas
16.
Xenobiotica ; 25(9): 993-1007, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8553692

RESUMEN

1. The pharmacokinetics and disposition of picumeterol, a novel beta 2 receptor agonist agent, have been studied in the rat and dog following administration by inhalation, intravenous and oral routes at various dose levels. 2. Picumeterol was found to be transferred across the lung of the rat and dog following inhalation dosage. After i.v. dosage picumeterol was eliminated from plasma with a half-life of about 1 h in the rat and about 2 h in the dog. Plasma clearance in the rat was about twice liver blood flow and the plasma levels of picumeterol were low after oral administration. 3. Following instillation of 14C-picumeterol to the trachea of isolated respiring rat lung preparations radioactivity was transferred from the airways to perfusion media as unchanged drug within 2 min. After 2 h perfusion, no metabolites were detected in the recirculation perfusate or lung. 4. Picumeterol was extensively metabolized in vivo in the rat (about 95%) and dog (about 90%) and in vitro in microsomal preparations of rat, dog and human liver. O-dealkylation and beta-oxidation are important as routes of metabolism. 5. Radioactivity was largely excreted in the urine of the rat and dog (> 50% of dose), as metabolites, following i.v. administration. There was some excretion of radioactivity in dog bile. Extensive first-pass metabolism was found after oral administration in the rat.


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 2 , Microsomas Hepáticos/metabolismo , Piridinas/farmacocinética , Administración por Inhalación , Administración Oral , Animales , Radioisótopos de Carbono , Perros , Femenino , Inyecciones Intravenosas , Masculino , Ratas , Ratas Wistar
19.
20.
Biometrics ; 24(2): 363-76, 1968 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-5683876
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