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1.
Proc Biol Sci ; 287(1938): 20201585, 2020 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-33171084

RESUMEN

Competition for shared resources represents a fundamental driver of biological diversity. However, the tempo and mode of phenotypic evolution in deep-time has been predominantly investigated using trait evolutionary models which assume that lineages evolve independently from each other. Consequently, the role of species interactions in driving macroevolutionary dynamics remains poorly understood. Here, we quantify the prevalence for signatures of competition between related species in the evolution of ecomorphological traits across the bird radiation. We find that mechanistic trait models accounting for the effect of species interactions on phenotypic divergence provide the best fit for the data on at least one trait axis in 27 out of 59 clades ranging between 21 and 195 species. Where it occurs, the signature of competition generally coincides with positive species diversity-dependence, driven by the accumulation of lineages with similar ecologies, and we find scarce evidence for trait-dependent or negative diversity-dependent phenotypic evolution. Overall, our results suggest that the footprint of interspecific competition is often eroded in long-term patterns of phenotypic diversification, and that other selection pressures may predominantly shape ecomorphological diversity among extant species at macroevolutionary scales.


Asunto(s)
Evolución Biológica , Aves , Animales , Fenotipo , Filogenia
2.
Ecol Lett ; 21(10): 1505-1514, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30133084

RESUMEN

Heterogeneity in rates of trait evolution is widespread, but it remains unclear which processes drive fast and slow character divergence across global radiations. Here, we test multiple hypotheses for explaining rate variation in an ecomorphological trait (beak shape) across a globally distributed group (birds). We find low support that variation in evolutionary rates of species is correlated with life history, environmental mutagenic factors, range size, number of competitors, or living on islands. Indeed, after controlling for the negative effect of species' age, 80% of variation in species-specific evolutionary rates remains unexplained. At the clade level, high evolutionary rates are associated with unusual phenotypes or high species richness. Taken together, these results imply that macroevolutionary rates of ecomorphological traits are governed by both ecological opportunity in distinct adaptive zones and niche differentiation among closely related species.


Asunto(s)
Evolución Biológica , Ecología , Animales , Masculino , Fenotipo , Filogenia
3.
Neuropsychologia ; 22(1): 65-72, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6709177

RESUMEN

A subject is described who can voluntarily select and hold either of two qualitatively different states of consciousness. Evidence is presented which confirmed differential left or right hemisphere dominance in each state. Asymmetries of EEG alpha and task performance scores indicated a state-dependent shift in functional lateralization. Evoked response studies showed directional changes in rate of interhemispheric transmission correlated with state-related hemisphere dominance. These findings demonstrated that capability for voluntary endogenous control of cerebral dominance under natural conditions.


Asunto(s)
Estado de Conciencia/fisiología , Dominancia Cerebral/fisiología , Adulto , Ritmo alfa , Femenino , Humanos , Conducción Nerviosa
4.
Science ; 156(3771): 14, 1967 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-17798618
5.
Otolaryngol Head Neck Surg ; 88(4): 491-9, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6821438

RESUMEN

The seventh cranial nerve spasms of the face and the eyelids, including essential blepharospasm, are usually intractable and sometimes disabling. Deanol acetamidobenzoate was compared with the anticholinergic orphenadrine for relief of these spasms. Deanol cured two of 16 (12%) subjects and improved a third. Orphenadrine was much more effective, improving the conditions of 16 of 26 (62%) subjects between 57% and 100%. A crossover double-blind experiment showed high significance over a placebo.


Asunto(s)
Deanol/uso terapéutico , Etanolaminas/uso terapéutico , Músculos Faciales/inervación , Nervio Facial , Orfenadrina/uso terapéutico , Espasmo/tratamiento farmacológico , Adulto , Anciano , Blefaroespasmo/tratamiento farmacológico , Método Doble Ciego , Evaluación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Distribución Aleatoria
6.
Hum Reprod Update ; 20(1): 141-51, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24173882

RESUMEN

BACKGROUND: At present, it is unclear which treatment strategy is best for couples with unexplained or mild male subfertility. We hypothesized that the prognostic profile influences the effectiveness of assisted conception. We addressed this issue by analysing individual patient data (IPD) from randomized controlled trials (RCTs). METHODS: We performed an IPD analysis of published RCTs on treatment strategies for subfertile couples. Eligible studies were identified from Cochrane systematic reviews and we also searched Medline and EMBASE. The authors of RCTs that compared expectant management (EM), intracervical insemination (ICI), intrauterine insemination (IUI), all three with or without controlled ovarian stimulation (COS) and IVF in couples with unexplained or male subfertility, and had reported live birth or ongoing pregnancy as an outcome measure, were invited to share their data. For each individual patient the chance of natural conception was calculated with a validated prognostic model. We constructed prognosis-by-treatment curves and tested whether there was a significant interaction between treatment and prognosis. RESULTS: We acquired data from 8 RCTs, including 2550 couples. In three studies (n = 954) the more invasive treatment strategies tended to be less effective in couples with a high chance of natural conception but this difference did not reach statistical significance (P-value for interaction between prognosis and treatment outcome were 0.71, 0.31 and 0.19). In one study (n = 932 couples) the strategies with COS (ICI and IUI) led to higher pregnancy rates than unstimulated strategies (ICI 8% versus 15%, IUI 13% versus 22%), regardless of prognosis (P-value for interaction in all comparisons >0.5), but at the expense of a high twin rate in the COS strategies (ICI 6% versus 23% and IUI 3% versus 30%, respectively). In two studies (n = 373 couples), the more invasive treatment strategies tended to be more effective in couples with a good prognosis but this difference did not reach statistical significance (P-value for interaction: 0.38 and 0.68). In one study (n = 253 couples) the differential effect of prognosis on treatment effect was limited (P-value for interaction 0.52), perhaps because prognosis was incorporated in the inclusion criteria. The only study that compared EM with IVF included 38 couples, too small for a precise estimate. CONCLUSIONS: In this IPD analysis of couples with unexplained or male subfertility, we did not find a large differential effect of prognosis on the effectiveness of fertility treatment with IUI, COS or IVF.


Asunto(s)
Infertilidad/terapia , Técnicas Reproductivas Asistidas , Femenino , Humanos , Masculino , Inducción de la Ovulación , Embarazo , Índice de Embarazo , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
13.
Ann Allergy ; 40(6): 393-8, 1978 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-666060

RESUMEN

A chemically defined diet of low allergenicity was used to provide complete nutritional support for a week in a referred group of 27 patients. Food-sensitive patients remitted 70% of their allergy symptoms, supporting a diagnosis of dominant food etiology. For those the diet was continued while selected foods were orally challenged. Safe diets were thus established in about three weeks of largely patient-executed effort. Patients without remission were given concentrated attention toward establishing other etiologies. Remission was thus achieved in 85% of the cases.


Asunto(s)
Hipersensibilidad a los Alimentos/dietoterapia , Adolescente , Adulto , Anciano , Dieta/efectos adversos , Femenino , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/etiología , Humanos , Masculino , Persona de Mediana Edad , Remisión Espontánea , Terapia Respiratoria/efectos adversos
14.
Cancer ; 38(1 SUPPL): 487-502, 1976 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-819124

RESUMEN

This paper presents preliminary data concerning the relationship of various components of glandular epithelium and effect of enzymes on metabolism, storage, and release of certain substances in normal and abnormal endometria. Activity of these endometrial enzymes has been compared between two groups: 252 patients with normal menstrual histories and 156 patients, all over the age of 40, with abnormal uterine bleeding. Material was obtained by endometrial biopsy or curettage. In the pathologic classification of the group of 156, 30 patients had secretory endometria, 88 patients had endometria classified as proliferative, 24 were classified as endometrial hyperplasia, and 14 were classified as adenocarcinoma. All tissue was studied by histologic, histochemical, and biochemical methods. Glycogen synthetase activity caused synthesis of glucose to glycogen, increasing in amount until midcycle, when glycogen phosphorylase activity caused the breakdown to glucose during the regressive stage of endometrial activity. This normal cyclic activity did not occur in the abnormal endometria, where activity of both enzymes continued at low constant tempo. Only the I form of glycogen synthetase increased as the tissue became more hyperplastic. With the constant glycogen content and the increased activity of both the TPN isocitric dehydrogenase and glucose-6-phosphate dehydrogenase in the hyperplastic and cancerous endometria, tissue energy was created, resulting in abnormal cell proliferation. These altered biochemical and cellular activities may be the basis for malignant cell growth.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Endometrio/metabolismo , Enfermedades Uterinas/metabolismo , Adenocarcinoma/metabolismo , Fosfatasa Alcalina/metabolismo , Permeabilidad de la Membrana Celular , Ciclo del Ácido Cítrico , Hiperplasia Endometrial/metabolismo , Endometrio/enzimología , Estradiol/farmacología , Femenino , Glucosafosfato Deshidrogenasa/metabolismo , Glucógeno/metabolismo , Glucógeno Sintasa/metabolismo , Hexosafosfatos/metabolismo , Humanos , Menstruación , Persona de Mediana Edad , Fosforilasas/metabolismo , Progestinas/farmacología , Neoplasias Uterinas/metabolismo
15.
Artículo en Inglés | MEDLINE | ID: mdl-2465888

RESUMEN

Brain-stem (BAEP) and middle-latency (MLAEP) auditory evoked potentials were recorded in zero noise and in 3 levels of continuous ipsilateral broadband noise. New information is presented on the effects of noise on BAEP wave I. Latency of wave I was not changed by increasing noise, but wave V latency linearly increased. Amplitude of waves I and V decreased non-linearly. The amplitude decrease was equivalent for both waves and occurred only at the higher noise levels. The dissociation of latency effects for waves I and V indicates a central component for the effect of noise on latency. The parallel amplitude change for waves I and V suggests a largely peripheral component. The MLAEP Pa latency also increased with increasing noise further supporting a central mechanism.


Asunto(s)
Tronco Encefálico/fisiología , Potenciales Evocados Auditivos , Ruido , Enmascaramiento Perceptual/fisiología , Adolescente , Adulto , Encéfalo/fisiología , Femenino , Humanos , Tiempo de Reacción , Nervio Vestibulococlear/fisiología
16.
Clin Orthop Relat Res ; (185): 203-6, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6705380

RESUMEN

Peripheral nerve injury occasionally results from long bone fractures, but bony entrapment of a peripheral nerve occurs infrequently. Bony entrapment of a peripheral nerve is usually associated with upper extremity fractures. In a 34-year-old man bony entrapment of the superficial peroneal nerve occurred in a healed midshaft fibular fracture. The patient complained of progressive pain over the distribution of the superficial peroneal nerve after sustaining a closed displaced tibial and fibular fracture that healed in nonanatomic alignment. Exploration revealed bony entrapment of the superficial peroneal nerve in the fracture callus, with reactive neuroma formation. Excision of the neuroma resulted in complete relief of the symptoms. Persistent pain over the distal anterolateral leg and dorsal foot following a fibular and tibial fracture is usually derived from a compartment syndrome. If this has been ruled out, the differential diagnosis should include bony entrapment of the superficial peroneal nerve.


Asunto(s)
Peroné/lesiones , Fracturas Óseas/complicaciones , Síndromes de Compresión Nerviosa/etiología , Nervio Peroneo/lesiones , Fracturas de la Tibia/complicaciones , Adulto , Humanos , Masculino , Síndromes de Compresión Nerviosa/cirugía
17.
J Am Aud Soc ; 5(1): 17-20, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-511653

RESUMEN

The repeatability of W-22 PB tests at levels of speech reception threshold (SRT) plus 5 to 30 dB in quiet and in white noise at S/N = 0 and 7 dB at a level of SRT plus 20 dB for 28 subjects with sensorineural hypoacusis. Standard deviations at various levels were from 9 to 13% compared to a standard deviation of less than 8% at SRT plus 40 dB. The lower variability at SRT plus 40 dB permits satisfactory confidence in the average of two measurements. However, it was found that more tests are required for the same confidence at the lower sensation levels. A protocol is suggested for carrying out this requirement.


Asunto(s)
Pérdida Auditiva Sensorineural/diagnóstico , Pruebas de Discriminación del Habla/normas , Prueba del Umbral de Recepción del Habla/normas , Adolescente , Adulto , Anciano , Niño , Humanos , Persona de Mediana Edad
18.
Int J Neurosci ; 27(1-2): 121-30, 1985 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4019059

RESUMEN

Interhemispheric transmission time (ITT) was derived from vibratory somatosensory evoked potentials (VSEP) arising in homologous cortical sensory--association areas of normals. Two different vibratory sources, an audiometer bone oscillator or an Optacon, were used to stimulate each index finger independently. ITT was calculated by subtracting the latency of the first major peak over the contralateral cortex (CL) from the latency of the corresponding peak over the ipsilateral area (IL-CL = ITT). Readily identified aberrant values were observed and rejected from the series of measurements leaving clear normal ranges. In addition to providing normal ITT data, clinical correlations were illustrated in two different disorders. Results suggested that important information relating to diagnosis and therapy of brain pathologies affecting interhemispheric transmission can now be made available in both experimental and clinical situations.


Asunto(s)
Agenesia del Cuerpo Calloso , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Encéfalo/fisiopatología , Potenciales Evocados Somatosensoriales , Vibración , Adolescente , Adulto , Anciano , Niño , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción/fisiología , Valores de Referencia
19.
Am J Otol ; 9(2): 122-6, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3407743

RESUMEN

Norepinephrine has been shown to improve signal-to-noise ratios of sensory systems, including that of the auditory system. Yohimbine has been observed to cause a selective increase of cerebral norepinephrine. It was administered in one dose to sensorineurally impaired subjects with the object of improving their speech hearing in noise. Speech intelligibility was measured by the adaptive procedure. Mild, significant improvement was noted in one of the hearing components, "attenuation," and an adverse effect was shown on "distortion," owing to noise. Auditory brainstem response was improved significantly. The objective of temporarily improving intelligibility in noise was not attained.


Asunto(s)
Encéfalo/efectos de los fármacos , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Norepinefrina/fisiología , Inteligibilidad del Habla/efectos de los fármacos , Yohimbina/uso terapéutico , Anciano , Audiometría de Respuesta Evocada , Encéfalo/metabolismo , Encéfalo/fisiopatología , Método Doble Ciego , Femenino , Pérdida Auditiva Sensorineural/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Ruido , Norepinefrina/metabolismo , Prueba del Umbral de Recepción del Habla
20.
Ann Allergy ; 49(5): 276-80, 1982 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7149341

RESUMEN

A diagnostic procedure developed for adults and children which includes a week-long fast nutritionally supported with a chemically defined diet was applied to a pilot group of children having ADD/HA syndrome. A probable etiology of food hypersensitivity was shown for a majority of the panel with several standard subjective tests. Three neurological tests, one of which was of the corpus callosum, were evaluated as objective measurements of ADD/HA. Management procedures are not discussed. A follow-up at one year showed substantial continuing control for many of the subjects. It is suggested that this type of general diagnostic procedure be employed to indicate for treatment those having food sensitivity as the primary etiology.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Hipersensibilidad a los Alimentos/diagnóstico , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/dietoterapia , Trastorno por Déficit de Atención con Hiperactividad/etiología , Niño , Diagnóstico Diferencial , Ayuno , Hipersensibilidad a los Alimentos/complicaciones , Humanos
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