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1.
Science ; 371(6525)2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33414190

RESUMEN

Phillips et al (Reports, 25 October 2019, p. 480) incorrectly conclude that tropical earthworm communities are less diverse and abundant than temperate communities. This result is an artifact generated by some low-quality datasets, lower sampling intensity in the tropics, different patterns in richness-area relationships, the occurrence of invasive species in managed soils, and a focus on local rather than regional richness.


Asunto(s)
Oligoquetos , Animales , Suelo
2.
Ecol Appl ; 21(7): 2349-56, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22073627

RESUMEN

Tropical soils are particularly vulnerable to fertility losses due to their low capacity to retain organic matter and mineral nutrients. This urges the development of new agricultural practices to manage mineral nutrients and organic matter in a more sustainable way while relying less on fertilizer inputs. Two methods pertaining to ecological engineering and agroecology have been tested with some success: (1) the addition of biochar to the soil, and (2) the maintenance of higher earthworm densities. However, modern crop varieties have been selected to be adapted to agricultural practices and to the soil conditions they lead to and common cultivars might not be adapted to new practices. Using rice as a model plant, we compared the responsiveness to biochar and earthworms of five rice cultivars with contrasted selection histories. These cultivars had contrasted responsivenesses to earthworms, biochar, and the combination of both. The mean relative increase in grain biomass, among all treatments and cultivars, was 94% and 32%, respectively, with and without fertilization. Choosing the best combination of cultivar and treatment led to a more than fourfold increase in this mean benefit (a 437% and a 353% relative increase in grain biomass, respectively, with and without fertilization). Besides, the more rustic cultivar, a local landrace adapted to diverse and difficult conditions, responded the best to earthworms in terms of total biomass, while a modern common cultivar responded the best in term of grain biomass. This suggests that cultivars could be selected to amplify the benefit of biochar- and earthworm-based practices. Overall, selecting new cultivars interacting more closely with soil organisms and soil heterogeneity could increase agriculture sustainability, fostering the positive feedback loop between soils and plants that has evolved in natural ecosystems.


Asunto(s)
Adaptación Fisiológica/genética , Oryza/genética , Oryza/fisiología , Suelo/química , Clima Tropical , Animales , Biomasa , Carbón Orgánico , Fertilizantes , Oligoquetos/fisiología
4.
Am J Occup Ther ; 55(1): 36-42, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11216364

RESUMEN

OBJECTIVES: A retrospective study was conducted to determine to what extent persons with postacute cerebrovascular accident (CVA) made progress toward rehabilitation goals during occupational therapy treatment and whether age and time since CVA onset affected the rate of goal achievement. METHOD: Data were collected from the admission and discharge records of persons with CVA who had received occupational therapy at a university clinic, who were at least 8 months post CVA, and who had not received therapy in the community for at least 6 months. The treatment was provided by occupational therapy students under supervision and had a mean length of 12 1-hr sessions over one semester. A sample size of 85 was obtained from 13 years of clinic records. RESULTS: All patients in the sample except one made progress toward at least one of their selected rehabilitation goals. The group mean score for goal progress indicated that as a whole, the patients made significant gains. In addition, independent t tests showed no significant differences in mean scores between younger and older patients, between longer and shorter times since onset, between men and women, or between right and left CVA. There was no significant linear association between mean score and the number of treatments received. CONCLUSION: Patients with CVA showed progress toward rehabilitation goals during postacute treatment. Patients with recent CVA onset or of younger age did not achieve goals at a significantly higher rate than those with less recent onset or of greater age.


Asunto(s)
Terapia Ocupacional , Rehabilitación de Accidente Cerebrovascular , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento
5.
J Nutr ; 124(3): 371-7, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8120656

RESUMEN

The purpose of this research was to determine the effect of vitamin K deficiency on indices of skeletal metabolism in laying hens, developing embryos and young growing chickens. Laying hens were fed a vitamin K-deficient diet for 28 wk, which resulted in impaired blood clotting and reduced bone gamma-carboxyglutamic acid (Gla) concentration compared with vitamin K-sufficient hens. However, this treatment did not influence egg production, eggshell deposition or other reproductive performance criteria. Vitamin K-deficient embryos were able to mobilize sufficient quantities of calcium for normal skeletal development, although they exhibited severe reduction in blood clotting and bone Gla concentration. Similar results were obtained from progeny of both vitamin K-sufficient and -deficient hens fed deficient diets for 4 wk after hatching. These results indicate that a severe reduction in skeletal protein Gla concentration does not interfere with normal development of this tissue.


Asunto(s)
Huesos/metabolismo , Pollos/metabolismo , Osteocalcina/metabolismo , Deficiencia de Vitamina K/metabolismo , Ácido 1-Carboxiglutámico/metabolismo , Animales , Coagulación Sanguínea/fisiología , Calcio/metabolismo , Embrión de Pollo/metabolismo , Pollos/crecimiento & desarrollo , Femenino , Reproducción/fisiología
6.
Ir Med J ; 85(1): 9-10, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1568857

RESUMEN

Three studies of intravenous heroin abusers, in electoral wards in the north and south of central Dublin and in Dun Laoghaire, were undertaken in 1982-84. One hundred and one out of the 203 intravenous injectors in these three studies are known to have been tested in Dublin for infection by the Human Immunodeficiency Virus (HIV) and 87 of the 101, or 86% are HIV Positive. Ninety two had also been tested for Hepatitis B infection (Hab) and 76 of the 92 were positive for the hepatitis antigen. The majority of those at present known to be HIV Positive in the Republic of Ireland are, or were, intravenous drug users.


Asunto(s)
Abuso de Sustancias por Vía Intravenosa/complicaciones , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Seropositividad para VIH , Hepatitis B/etiología , Antígenos de Superficie de la Hepatitis B/inmunología , Humanos , Irlanda/epidemiología , Masculino , Abuso de Sustancias por Vía Intravenosa/epidemiología
7.
Anesth Analg ; 68(5): 614-8, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2719292

RESUMEN

This study was undertaken to evaluate the mental recovery of patients following cataract operations under neuroleptanalgesia. Mental function was assessed by Mini-Mental State (MMS) preoperatively and at 6 and 24 hours postoperatively. Preoperatively, 18.7% of the elderly had cognitive impairment of mental function while none in the younger group had any impairment (P less than 0.02). At six hours postoperatively, 29.7% of the elderly had cognitive impairment compared with 4% of the younger group (P less than 0.01). At 24 hours postoperatively, the percentage of elderly and younger patients with cognitive impairment had returned to preoperative levels. Baseline score and age were found to be significant predictors (P less than 0.004) of the 6-hour score and 24-hour score. In conclusion, cognitive impairment of mental function occurred in patients undergoing cataract operation with retrobulbar block and intravenous sedation at 6 hours postoperatively; MMS has the potential for use as a screening preoperative test for outpatients to identify those at risk for developing cognitive impairment.


Asunto(s)
Extracción de Catarata , Trastornos del Conocimiento/etiología , Neuroleptanalgesia/efectos adversos , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Análisis de Regresión
8.
Anesthesiology ; 69(3): 343-7, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2458058

RESUMEN

This study aimed to detect the difference in hemodynamic and electrocardiographic responses during the prebypass period in patients undergoing coronary bypass grafting who were receiving beta-adrenergic blocking drugs, calcium entry blocking drugs, or both beta-adrenergic and calcium entry blocking drugs. Electrocardiographic evidence of myocardial ischemia was noted significantly more frequently in patients receiving calcium entry blocking drugs alone at induction of anesthesia (P less than 0.03), skin incision (P less than 0.05), and sternotomy (P less than 0.002). Heart rate at sternotomy was significantly higher in patients receiving calcium entry blocking drugs (P less than 0.02) as compared to patients receiving beta-adrenergic blocking drugs or the combination of both drugs. In conclusion, patients treated with calcium entry blocking drugs alone had significantly higher incidence of perioperative ischemic ECG changes compared with patients receiving beta-adrenergic blocking drugs alone or in combination with calcium channel blocking drugs.


Asunto(s)
Calcio/metabolismo , Enfermedad Coronaria/prevención & control , Complicaciones Intraoperatorias/prevención & control , Canales Iónicos/efectos de los fármacos , Antagonistas Adrenérgicos beta/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Puente de Arteria Coronaria , Enfermedad Coronaria/fisiopatología , Evaluación de Medicamentos , Quimioterapia Combinada , Electrocardiografía , Hemodinámica/efectos de los fármacos , Humanos , Cuidados Intraoperatorios/métodos , Complicaciones Intraoperatorias/fisiopatología , Estudios Prospectivos
9.
Intensive Care Med ; 14(1): 50-4, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3343430

RESUMEN

The oxygen cost of breathing (which is the difference in oxygen consumption measured during controlled ventilation and again during spontaneous ventilation) was measured in 30 patients between the ages of 17 and 96 years at the time of commencement of weaning from mechanical ventilation. There was a significant exponential correlation between the oxygen cost of breathing in ml/m2/min and the oxygen cost of breathing as a percentage of total oxygen consumption during spontaneous ventilation (OCB/VO2SV%) and the duration of weaning in days.


Asunto(s)
Consumo de Oxígeno , Respiración Artificial , Trabajo Respiratorio , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cuidados Críticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Respiración
10.
Clin Chem ; 33(6): 1083-4, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3594803

RESUMEN

As is well recognized, activities of creatine kinase (CK, EC 2.7.3.2) and lactate dehydrogenase (EC 1.1.1.27) in plasma may be substantially increased in hypothyroidism. We emphasize here that an increase and decrease in CK-MB isoenzyme, characteristic of acute myocardial infarction, can occur in hypothermic myxedema coma without myocardial infarction.


Asunto(s)
Coma/diagnóstico , Creatina Quinasa/sangre , Hipotermia/diagnóstico , Infarto del Miocardio/diagnóstico , Mixedema/diagnóstico , Anciano , Errores Diagnósticos , Femenino , Humanos , Hipotermia/enzimología , Isoenzimas , Infarto del Miocardio/enzimología , Mixedema/enzimología
11.
Can Anaesth Soc J ; 33(5): 571-7, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3021300

RESUMEN

The synergistic effect of pancuronium bromide (PCB) and d-tubocurarine (DTC) on the onset time of neuromuscular blockade was tested in 108 ASA physical status I and II adults anaesthetized with thiopentone, nitrous oxide and halothane. Either saline or a small (priming) dose (DTC, 0.04 mg X kg-1, or PCB, 0.007 mg X kg-1) was administered 3 min before a paralyzing dose of either DTC or PCB. The total dose of relaxant was equivalent to DTC, 0.4 mg X kg-1, or PCB, 0.07 mg X kg-1. Neuromuscular activity was measured using train-of-four stimulation applied every 12 s. Time to 50 per cent first twitch blockade was 63 +/- 4.6 s (mean +/- SEM) with DTC and 88 +/- 5.2 s with PCB (p less than 0.002). Times to 90 per cent blockade were not different between the two drugs (161 +/- 20 s and 141 +/- 21 s respectively). Priming a DTC blockade with either DTC or PCB or priming a PCB blockade with PCB produced an acceleration of less than 10 s at all levels of blockade. Compared with PCB alone, priming PCB blockade with DTC reduced the time to 50 per cent blockade to 71 +/- 4.5 s (p less than 0.02) and to 90 per cent blockade to 111 +/- 8 s (p less than 0.05). Priming did not affect the duration of action significantly, except in the case of PCB priming of DTC, where duration was increased from 39 +/- 4.4 to 57 +/- 4 min (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Anestesia , Pancuronio , Tubocurarina , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Bloqueantes Neuromusculares , Pancuronio/administración & dosificación , Transmisión Sináptica/efectos de los fármacos , Factores de Tiempo , Tubocurarina/administración & dosificación
13.
Prostaglandins ; 17(6): 891-901, 1979 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-574304

RESUMEN

Effects of PGE1 or PGE2 on luteal function were studied in 163 pseudopregnant rats. PGE1 (10, 100, or 300 micrograms) given intrauterine every 6 hr did not shorten pseudopregnancy (P greater than 0.05), however, the same doses of PGE2 given intrauterine every 6 hr advanced luteolysis (P less than 0.05). PGE1 (100 or 300 micrograms) given every 4 hr intramuscular maintained levels of progesterone in peripheral blood above controls (P less than 0.05) while 100 or 300 micrograms of PGE2 hastened the decline in progesterone (P less than 0.05). The antiluteolytic effect of PGE1 was not via an inhibition of PGF secretion (P greater than 0.05) by the uterus or by induction of ovulation in treated animals. Moreover, PGE1 (100, 200, or 500 micrograms) given intramuscular every 4 hr from day 4 of pseudopregnancy until the next proestrus delayed luteal regression around 3 days (P less than 0.05). PGE2 at doses of 100, 200, or 500 micrograms every 4 hr given intramuscular consistently shortened pseudopregnancy (P less than 0.05). Lower doses were without effect (P greater than 0.05). Based on the above data it is concluded that PGE2 is consistently luteolytic whereas PGE1 is not luteolytic in pseudopregnant rats and that PGE1 may be an antiluteolysin.


Asunto(s)
Cuerpo Lúteo/efectos de los fármacos , Luteolíticos , Prostaglandinas F/farmacología , Seudoembarazo/metabolismo , Animales , Castración , Estro/efectos de los fármacos , Femenino , Embarazo , Progesterona/sangre , Prostaglandinas E/administración & dosificación , Ratas
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