Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
J Dairy Sci ; 100(3): 1795-1811, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28041740

RESUMEN

Improving body condition score of thin cows in late lactation is necessary, because cows that are thin at drying off exhibit decreased fertility postpartum and are at increased risk of disease and of being culled in the subsequent lactation. Offering a diet low in crude protein (CP) content in late lactation may help to improve body condition score (BCS) at drying off, whereas imposing an extended dry period (EDP) has been advocated as another way to increase BCS at calving. To test these hypotheses, 65 thin cows (mean BCS 2.25 at 14 wk precalving) were managed on 1 of 3 treatments between 13 and 9 wk prepartum: normal protein control {NP; grass silage + 5 kg/d of a normal protein concentrate [228 g of CP/kg of dry matter (DM)]}, low protein [LP; grass silage + 5 kg/d of a low-protein concentrate (153 g of CP/kg of DM)], or EDP (cows dried off at 13 wk precalving and offered a grass silage-only diet). Both NP and LP cows were dried off at wk 8 prepartum, after which all cows were offered a grass silage-only diet until calving. After calving, all cows were offered a common diet (supplying 11.1 kg of concentrate DM/cow per day) for 19 wk. Between 13 and 9 wk prepartum, LP cows had lower DM intake, milk yield, and body weight than NP cows. Whereas EDP cows had lower serum ß-hydroxybutyrate and fatty acid concentrations than those of NP cows, BCS at wk 9 prepartum did not differ between treatments. Cows on the LP treatment continued to have lower DMI and BW than those of NP and EDP cows between 8 wk prepartum and calving, but only EDP cows had a higher BCS at calving. Treatment did not affect calving difficulty score or calf birth weight. Although all cows were offered a common diet postpartum, cows on the LP treatment had lower DM intake and milk fat + plus protein yield than cows on any other treatment during the 19-wk period postpartum, but we found no differences in any postpartum indicator of body tissue reserves. The treatments imposed from wk 13 to 9 prepartum had no effect on any fertility or health parameters examined postpartum. Extending the dry period for thin cows improved their BCS at calving but did not allow these cows to achieve the target BCS of 2.75, and we found no beneficial effects of this treatment on cow performance postpartum. Offering a lower-protein diet to thin cows in late lactation did not improve BCS at calving above that of cows on a normal protein diet, but had unexplained long-term negative effects on cow performance.


Asunto(s)
Lactancia , Leche/metabolismo , Ácido 3-Hidroxibutírico/sangre , Animales , Bovinos , Dieta/veterinaria , Femenino , Periodo Posparto
2.
J Dairy Sci ; 97(11): 7043-53, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25173463

RESUMEN

Although the effect of nutrition on enteric methane (CH4) emissions from confined dairy cattle has been extensively examined, less information is available on factors influencing CH4 emissions from grazing dairy cattle. In the present experiment, 40 Holstein-Friesian dairy cows (12 primiparous and 28 multiparous) were used to examine the effect of concentrate feed level (2.0, 4.0, 6.0, and 8.0 kg/cow per day; fresh basis) on enteric CH4 emissions from cows grazing perennial ryegrass-based swards (10 cows per treatment). Methane emissions were measured on 4 occasions during the grazing period (one 4-d measurement period and three 5-d measurement periods) using the sulfur hexafluoride technique. Milk yield, liveweight, and milk composition for each cow was recorded daily during each CH4 measurement period, whereas daily herbage dry matter intake (DMI) was estimated for each cow from performance data, using the back-calculation approach. Total DMI, milk yield, and energy-corrected milk (ECM) yield increased with increasing concentrate feed level. Within each of the 4 measurement periods, daily CH4 production (g/d) was unaffected by concentrate level, whereas CH4/DMI decreased with increasing concentrate feed level in period 4, and CH4/ECM yield decreased with increasing concentrate feed level in periods 2 and 4. When emissions data were combined across all 4 measurement periods, concentrate feed level (2.0, 4.0, 6.0, and 8.0 kg/d; fresh basis) had no effect on daily CH4 emissions (287, 273, 272, and 277 g/d, respectively), whereas CH4/DMI (20.0, 19.3, 17.7, and 18.1g/kg, respectively) and CH4-E/gross energy intake (0.059, 0.057, 0.053, and 0.054, respectively) decreased with increasing concentrate feed levels. A range of prediction equations for CH4 emissions were developed using liveweight, DMI, ECM yield, and energy intake, with the strongest relationship found between ECM yield and CH4/ECM yield (coefficient of determination = 0.50). These results demonstrate that offering concentrates to grazing dairy cows increased milk production per cow and decreased CH4 emissions per unit of milk produced.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Bovinos/fisiología , Industria Lechera , Ingestión de Energía , Metano/metabolismo , Alimentación Animal/análisis , Animales , Relación Dosis-Respuesta a Droga , Femenino , Lactancia/fisiología , Leche/química , Leche/metabolismo , Estado Nutricional , Distribución Aleatoria
3.
Am J Audiol ; 8(1): 57-64, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10499120

RESUMEN

Nonfatal penetrating injuries to the brainstem offer a unique opportunity to assess subcortical auditory pathway function. A case study of a patient suffering a severe nailgun accident is presented. Hearing sensitivity and acoustic reflexes were normal bilaterally, but word recognition was reduced for one ear. Auditory brainstem response results indicated waves I-IV were present bilaterally, but wave V was absent bilaterally. Results of vestibular findings indicated central pathology also. Results of audiologic, vestibular, radiologic, neurologic, and physical medicine examinations are discussed.


Asunto(s)
Tronco Encefálico/lesiones , Heridas Penetrantes/rehabilitación , Adulto , Vías Auditivas/fisiopatología , Tronco Encefálico/diagnóstico por imagen , Tronco Encefálico/fisiopatología , Humanos , Masculino , Radiografía , Vestíbulo del Laberinto/fisiopatología , Heridas Penetrantes/diagnóstico por imagen , Heridas Penetrantes/cirugía
4.
Clin Oncol (R Coll Radiol) ; 10(1): 18-23, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9543610

RESUMEN

The availability and use of 3D treatment planning facilities in the UK was investigated by questionnaire. Fifty-eight of the 62 UK radiotherapy centres responded (94%). There was considerable variation in the facilities available and in the manner in which they were used. Although 36 centres (62%) have the facilities to undertake complex, non-coplanar treatment planning, only 12 did so on a regular basis. More surprising was the inconsistent implementation of coplanar CT planning. It is suggested that we need to work towards reaching a consensus on best practice in radiotherapy planning. This will require the creation of systems for guidance and further training of the various staff involved.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador/estadística & datos numéricos , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Instituciones de Atención Ambulatoria/estadística & datos numéricos , Humanos , Auditoría Administrativa , Auditoría Médica , Programas Informáticos , Encuestas y Cuestionarios , Tomografía Computarizada por Rayos X/instrumentación , Reino Unido
5.
Mayo Clin Proc ; 69(11): 1027-39, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7967754

RESUMEN

OBJECTIVE: To report a cost-effective and scientifically based algorithm for the clinical assessment and treatment of patients with transient ischemic attack (TIA) or minor ischemic stroke. DESIGN: We comprehensively reviewed the literature on the epidemiologic features, assessment approaches, and treatment recommendations for ischemic cerebrovascular disease and developed an algorithm by using the available clinical and research data to support all decision-making steps. MATERIAL AND METHODS: For patients with TIA or minor ischemic stroke, the appropriate setting for investigation (inpatient or outpatient), suggested diagnostic tests, use of anticoagulants and antiplatelet agents, and indications for surgical treatment are reviewed. RESULTS: Although stroke is a common cause of death and lost productivity in the United States, the clinical assessment of patients with TIA or minor ischemic stroke has lacked consistency. The simplified algorithm clarifies patients who may be candidates for hospitalization and possible anticoagulation therapy. Initial diagnostic studies should include computed tomography of the head without use of a contrast agent, which quickly distinguishes nonhemorrhagic from hemorrhagic cerebrovascular disease. Evolving noninvasive studies of the cerebral vasculature are providing increasingly sensitive means of detecting stenoses, yet cerebral angiography remains the "gold standard." Treatment options depend on the pathophysiologic findings on diagnostic evaluation. CONCLUSION: The assessment of patients with ischemic cerebrovascular disease is complex. The simplified algorithmic approach reported herein necessitates entry of appropriate patients into the algorithm. Because of clinical heterogeneity, an algorithm may apply to a wide spectrum of patients but will not cover every situation; hence, evaluation must be guided by a patient's unique history and findings on examination and by the physician's clinical experience.


Asunto(s)
Algoritmos , Trastornos Cerebrovasculares/diagnóstico , Trastornos Cerebrovasculares/terapia , Ataque Isquémico Transitorio/diagnóstico , Ataque Isquémico Transitorio/terapia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatología , Isquemia Encefálica/terapia , Circulación Cerebrovascular , Trastornos Cerebrovasculares/fisiopatología , Humanos , Ataque Isquémico Transitorio/fisiopatología
6.
Neurosurgery ; 24(2): 171-8, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2645540

RESUMEN

The natural history of postirradiation extracranial cerebrovascular disease is uncertain. Previous reported cases spanning 20 years of carotid surgery are difficult to evaluate, because patients may sometimes have unspecified symptoms, physical examinations, postoperative results, and follow-up. Also, the evolution of carotid surgery over the past two decades makes it impossible to compare earlier operative technique with the state-of-the-art technique of today. Our series of 7 patients underwent 9 carotid endarterectomies with an average follow-up period of 46 months. The number of patients is small, and although technically this is a more difficult operation, we feel the results are favorable and may be comparable with endarteerctomy procedures in nonirradiated patients. These patients should be approached as if radiation changes are not a major factor when they are considered for reconstructive arterial surgery.


Asunto(s)
Enfermedades de las Arterias Carótidas/etiología , Arteriosclerosis Intracraneal/etiología , Radioterapia/efectos adversos , Anciano , Arterias Carótidas/efectos de la radiación , Enfermedades de las Arterias Carótidas/cirugía , Endarterectomía , Humanos , Arteriosclerosis Intracraneal/cirugía , Masculino , Persona de Mediana Edad
7.
Arch Neurol ; 45(4): 472-5, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3355404

RESUMEN

In the case described, electroencephalography (EEG) proved valuable for determining the nature of spells of loss of consciousness with brief clonic jerks associated with ear and throat pain. A 70-year-old woman had a history of episodic brief attacks of pain below the right ear and deep in the neck that had started three years previously. The spells became more severe and progressed to loss of awareness associated with clonic jerks of the extremities. Because of a concern that the spells represented seizures, an EEG was performed, with electrocardiographic monitoring. Multiple spells were recorded; they began with profound bradycardia followed by generalized slow-wave activity and then by suppression of all EEG activity correlating with loss of consciousness and clonic jerking. The spells were thought to represent syncopal attacks associated with glossopharyngeal neuralgia.


Asunto(s)
Encéfalo/fisiopatología , Electroencefalografía , Nervio Glosofaríngeo/fisiopatología , Neuralgia/fisiopatología , Síncope/fisiopatología , Anciano , Bradicardia/complicaciones , Bradicardia/fisiopatología , Electrocardiografía , Femenino , Corazón/fisiopatología , Humanos , Neuralgia/complicaciones , Síncope/complicaciones
8.
Arch Neurol ; 40(3): 155-8, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6830455

RESUMEN

Brainstem auditory evoked potentials (BAEPs) were obtained in 20 patients with palatal myoclonus. The group included 14 men and six women whose ages ranged from 19 to 82 years. Six of the patients had abnormal BAEPs: two with severe head trauma and one each with a brainstem infarct, tumor, demyelination, and an indeterminate inflammatory process. The 14 patients with normal BAEPs had palatal myoclonus secondary to head trauma (five patients), brainstem infarcts (four patients), cerebellar tumors (two patients), degenerative processes (two patients), and an Arnold-Chiari malformation (one patient). Since the auditory pathways are separate from the structures associated with palatal myoclonus, it is possible to have discrete lesions producing palatal myoclonus with sparing of the auditory structures, whereas diffuse or multifocal lesions of the brainstem are more likely to be associated with abnormal BAEPs.


Asunto(s)
Tronco Encefálico/fisiopatología , Potenciales Evocados Auditivos , Mioclonía/fisiopatología , Paladar Blando/fisiopatología , Adulto , Anciano , Encefalopatías/complicaciones , Lesiones Encefálicas/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mioclonía/complicaciones
10.
Mayo Clin Proc ; 51(7): 417-29, 1976 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-180358

RESUMEN

Insulinoma is a rare tumor, occurring more often in women and in the older age range. Eighty percent of patients have a single benign tumor, usually less than or equal to 2 cm in diameter, located with about equal frequency in body, head, or tail of the pancreas and amenable to surgical cure. About 10% have multiple tumors; in this group there is a high incidence of multiple endocrine neoplasia type I syndrome. The remaining 10% of patients have metastatic malignant insulinoma. Symptoms are intermittent, recur at irregular intervals in the food-deprived state over a median of 1 1/2 years, and arise from varying degrees of neuroglycopenia. Symptoms often lead to misdiagnosis as a neurologic or psychiatric disorder. Transient neurologic deficits and EEG abnormalities can be observed during hypoglycemia. Diagnosis requires repeated demonstration of hypoglycemia (glucose less than or equal to 40 mg/dl) during spontaneous or provoked symptoms, relief with ingestion of carbohydrates, simultaneous hyperinsulinemia (serum insulin greater than 6 muU/ml), and absence of insulin antibodies. A useful diagnostic adjunct is the intravenous tolbutamide test, for which new diagnostic criteria are presented.


Asunto(s)
Adenoma de Células de los Islotes Pancreáticos/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Adenoma de Células de los Islotes Pancreáticos/sangre , Adenoma de Células de los Islotes Pancreáticos/cirugía , Adolescente , Adulto , Anciano , Glucemia/análisis , Errores Diagnósticos , Electroencefalografía , Femenino , Prueba de Tolerancia a la Glucosa , Hormonas Ectópicas/sangre , Humanos , Hipoglucemia/sangre , Hipoglucemia/diagnóstico , Insulina/sangre , Masculino , Persona de Mediana Edad , Manifestaciones Neurológicas , Pancreatectomía , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/cirugía , Tolbutamida
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...