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1.
Anaesthesia ; 74(5): 594-601, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30687939

RESUMEN

Rib fractures are associated with significant morbidity and mortality. Ultrasound-guided thoracic paravertebral catheter insertion has been described for the management of pain secondary to rib fractures. We conducted a retrospective observational study of all patients with rib fractures who had a paravertebral catheter inserted for analgesia provision over a 4-year period. Data from the Trauma Audit and Research Network were used to compare patients with rib fractures who were managed with paravertebral catheters to those managed with systemic analgesia. A total of 314 consecutive paravertebral catheters were inserted in 290 patients. Five (1.9%) catheters were removed due to ineffective analgesia. Other minor complications occurred in three cases (0.96%). The proportion of rib fracture patients managed with paravertebral catheters increased from 31/200 (15.5%) in the first year of study to 81/168 (48.2%) in the fourth; over this time-period the observed:predicted mortality ratio fell from 1.04 to 0.66. Proportional hazard regression with and without propensity score matching demonstrated a reduction in mortality associated with paravertebral catheter use, but this became statistically non-significant when time-dependent analysis was used. Paravertebral catheters are a safe and effective technique for rib fracture analgesia; however, our data were insufficient to demonstrate any improvement in mortality.


Asunto(s)
Bloqueo Nervioso/métodos , Manejo del Dolor/métodos , Dolor/etiología , Dolor/prevención & control , Fracturas de las Costillas/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Anestésicos Locales/administración & dosificación , Inglaterra/epidemiología , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Bloqueo Nervioso/efectos adversos , Dimensión del Dolor/métodos , Estudios Retrospectivos , Fracturas de las Costillas/mortalidad , Vértebras Torácicas/diagnóstico por imagen , Ultrasonografía Intervencional/métodos
2.
Int J Cosmet Sci ; 37(1): 116-22, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25376840

RESUMEN

OBJECTIVE: To determine whether the coordination environment of copper in hair is affected by the shampoo used. METHODS: Electron paramagnetic resonance (EPR) spectroscopy to discriminate between mixed oxygen/nitrogen and mixed oxygen/sulphur coordination of copper after treatment with two different shampoos. RESULTS: Copper with mixed oxygen/nitrogen coordination could be converted to mixed oxygen/sulphur coordination by treating with the appropriate shampoo, but this was not reversible with the products tested, although copper was removed from hair at very high pH values. CONCLUSION: Commercial hair treatment products can have a profound effect on the copper coordination environment in hair, and this must be taken into account in any attempt to use hair as a health marker.


Asunto(s)
Cobre/análisis , Cabello/química , Espectroscopía de Resonancia por Spin del Electrón , Humanos
3.
J Appl Microbiol ; 116(5): 1241-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24460572

RESUMEN

AIMS: Examine the regulation of a spore coat protein and the effects on spore properties. METHODS AND RESULTS: A c. 23 kDa band in coat/exosporial extracts of Bacillus anthracis Sterne spores varied in amount depending upon the conditions of sporulation. It was identified by MALDI as a likely orthologue of ExsB of Bacillus cereus. Little if any was present in an exosporial preparation with a location to the inner coat/cortex region established by spore fractionation and immunogold labelling of electron micrograph sections. Because of its predominant location in the inner coat, it has been renamed Cotγ. It was relatively deficient in spores produced at 37°C and when acidic fermentation products were produced a difference attributable to transcriptional regulation. The deficiency or absence of Cotγ resulted in a less robust exosporium positioned more closely to the coat. These spores were less hydrophobic and germinated somewhat more rapidly. Hydrophobicity and appearance were rescued in the deletion strain by introduction of the cotγ gene. CONCLUSIONS: The deficiency or lack of a protein largely found in the inner coat altered spore hydrophobicity and surface appearance. SIGNIFICANCE AND IMPACT OF THE STUDY: The regulated synthesis of Cotγ may be a paradigm for other spore coat proteins with unknown functions that modulate spore properties in response to environmental conditions.


Asunto(s)
Bacillus anthracis/genética , Proteínas Bacterianas/biosíntesis , Bacillus anthracis/química , Bacillus anthracis/metabolismo , Proteínas Bacterianas/análisis , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Interacciones Hidrofóbicas e Hidrofílicas , Esporas Bacterianas/química , Esporas Bacterianas/genética , Esporas Bacterianas/ultraestructura , Propiedades de Superficie , Transcripción Genética
4.
Pain Med ; 15(9): 1496-507, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25159869

RESUMEN

OBJECTIVES: This cross-sectional study examines to whom and how fully sickle cell disease (SCD) patients talk to others about sickle cell pain, how helpful it is to talk with others about these pain episodes, and the association between talking to others about sickle cell pain episodes and patients' psychological adjustment and coping strategies in managing the disease. METHODS: A convenience sample of 73 African American patients with SCD (30 men and 43 women), were recruited from two SCD clinics at the time of routine medical visits. Most participants had been diagnosed with hemoglobin SS, and they reported an average number of 8.61 pain episodes in the previous 12 months. Participants were asked to whom, how fully, and how helpful it was to talk to significant others about SCD pain episodes experienced in the last 12 months. Patients also completed measures of their psychological adjustment as well as how they would manage a future sickle cell pain episode. Self-report ratings were made on Likert-type scales. RESULTS: Based on paired samples t-tests, participants talked significantly more fully about their thoughts and feelings concerning pain episodes to God and to their primary medical providers than to either their parents, siblings, or an intimate partner/close friend. Bivariate correlations indicated that amount and helpfulness of talking about pain episodes to God and to parents were significantly associated with better psychological adjustment on selected measures. Also, bivariate correlations indicated that helpfulness in talking with siblings, intimate partner/close friend, and primary medical providers was positively related with willingness to go to a physician in the event of a future pain episode. CONCLUSIONS: The results document to whom and how helpful it is to talk with others about SCD pain episodes and how SCD disclosure is related to strategies for managing this disease.


Asunto(s)
Adaptación Psicológica , Anemia de Células Falciformes/psicología , Negro o Afroamericano/psicología , Relaciones Interpersonales , Dolor/psicología , Autorrevelación , Apoyo Social , Adolescente , Adulto , Anciano , Actitud Frente a la Salud , Comunicación , Estudios Transversales , Femenino , Amigos , Humanos , Masculino , Persona de Mediana Edad , Dolor/tratamiento farmacológico , Padres , Aceptación de la Atención de Salud/psicología , Médicos de Atención Primaria , Religión , Autoinforme , Parejas Sexuales , Hermanos , Factores Socioeconómicos , Adulto Joven
6.
Public Health ; 128(12): 1059-65, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25443102

RESUMEN

The threat posed to global health by climate change has been widely discussed internationally. The United Kingdom public health community seem to have accepted this as fact and have called for urgent action on climate change, often through state interventionist mitigation strategies and the adoption of a risk discourse. Putting aside the climate change deniers' arguments, there are critics of this position who seem to accept climate change as a fact but argue that the market and/or economic development should address the issue. Their view is that carbon reduction (mitigation) is a distraction, may be costly and is ineffective. They argue that what is required is more economic development and progress even if that means a warmer world. Both positions however accept the fact of growth based capitalism and thus fail to critique neoliberal market driven capitalism or posit an alternative political economy that eschews growth. Ecological public health, however, appears to be a way forward in addressing not only social determinants of health but also the political and ecological determinants. This might allow us to consider not just public health but also planetary health and health threats that arise from growth based capitalism.


Asunto(s)
Cambio Climático , Disentimientos y Disputas , Fenómenos Ecológicos y Ambientales , Salud Pública , Salud Global , Humanos , Política
7.
J Wound Care ; 23(4): 165-6, 168, 170-2 passim, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24762380

RESUMEN

OBJECTIVE: Repeated hospital admissions (RHA) for ongoing pressure ulcer (PU) care remains a significant challenge in the clinical management of the spinal cord injury/disorders (SCI/D) population. The current study investigated the significance of risk factors for PU treatment and RHA. METHOD: A retrospective chart review of veterans admitted to the Louis Stokes Cleveland Department of Veterans Affairs Medical Center (LSCDVAMC) Spinal Cord Injury (SCI) unit for Category III or IV PUs was carried out. A random sample of 105 individuals with SCI/D, evaluated by the Wound Care Team (WCT) from 2006 to 2009 was assessed. Multiple PU development risk factors were extracted from the electronic health record system using standardised data collection forms and entered into the Spinal Cord Injury Pressure Ulcer Database (SCIPUD). Potential associations with RHA were analysed. RESULTS: Twenty variables were initially identified as potentially related to PU development. Descriptive statistics and statistically significant associations between risk factors and RHA were determined. Demographic factors showed no significant association with RHA. Duration of injury, power wheelchair use and sub-optimally managed spasticity (SMS) were significantly associated with higher RHA. Sub-optimally managed neurogenic bowel (SMNB) at admission was significantly associated with reduced RHA. CONCLUSION: Factors previously found to be predictive of initial PU development may not, in fact, be predictive of RHA. Some protective trends were observed, such as polypharmacy and marital status, but these did not reach statistical significance in this preliminary study of admission characteristics, warranting further research. DECLARATION OF INTEREST: There were no external sources of funding for this study. The authors have no conflicts of interests to declare.


Asunto(s)
Readmisión del Paciente/estadística & datos numéricos , Úlcera por Presión/terapia , Traumatismos de la Médula Espinal/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hospitales de Veteranos , Humanos , Masculino , Persona de Mediana Edad , Espasticidad Muscular/complicaciones , Intestino Neurogénico/complicaciones , Ohio , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Silla de Ruedas
8.
J Wound Care ; 22(2): 90-2, 94-7, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23665664

RESUMEN

OBJECTIVE: To investigate the hypothesis that stereophotogrammetric wound size monitoring shows suitable inter-observer reliability and user acceptance for clinical practice use. METHOD: Veterans admitted for conservative management of severe pressure ulcers were eligible for inclusion in the study. Three-dimensional (3D) digital wound images were independently captured by two expert and two non-expert nurse-observers using a commercially available stereophotogrammetry system,weekly for 6 weeks.A double-blinded analyst generated 3D wound reconstructions, using software to determine geometry. Clinical opinion of wound progression was provided by an expert physician. RESULTS: Thirteen wounds were assessed with more than 80% of all images being readable. Interclass correlation of 0.9867 (p < 0.000 I) was observed. Compared with clinical opinion, 3D wound measurement was sensitive between improving and static wounds for wound perimeter, volume, depth and length. CONCLUSION: These preliminary findings suggest that 3D wound measurement minimises differences in wound measurement between expert and non-expert observers, suggesting it could be implemented with high reliability in health-care settings where several observers are involved in wound care management.


Asunto(s)
Fotogrametría/enfermería , Úlcera por Presión/patología , Adulto , Actitud del Personal de Salud , Método Doble Ciego , Humanos , Imagenología Tridimensional , Variaciones Dependientes del Observador , Fotogrametría/métodos , Úlcera por Presión/enfermería , Estudios Prospectivos , Reproducibilidad de los Resultados , Veteranos
9.
Nat Genet ; 22(2): 151-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10369256

RESUMEN

Neurospora crassa ARG13 and Saccharomyces cerevisiae ARG11 encode mitochondrial carrier family (MCF) proteins that transport ornithine across the mitochondrial inner membrane. We used their sequences to identify EST candidates that partially encode orthologous mammalian transporters. We thereby identified such a gene (ORNT1) that maps to 13q14 and whose expression, similar to that of other urea cycle (UC) components, was high in liver and varied with changes in dietary protein. ORNT1 expression restores ornithine metabolism in fibroblasts from patients with hyperammonaemia-hyperornithinaemia-homocitrullinuria (HHH) syndrome. In a survey of 11 HHH probands, we identified 3 ORNT1 mutant alleles that account for 21 of 22 possible mutant ORNT1 genes in our patients: F188delta, which is common in French-Canadian HHH patients and encodes an unstable protein; E180K, which encodes a stable, properly targeted protein that is inactive; and a 13q14 microdeletion. Our results show that ORNT1 encodes the mitochondrial ornithine transporter involved in UC function and is defective in HHH syndrome.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/genética , Amoníaco/sangre , Proteínas Portadoras/genética , Cromosomas Humanos Par 13 , Citrulina/metabolismo , Proteínas de Transporte de Membrana , Ornitina/sangre , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Sistemas de Transporte de Aminoácidos Básicos , Animales , Canadá , Proteínas Portadoras/biosíntesis , Proteínas Portadoras/química , Mapeo Cromosómico , Femenino , Francia/etnología , Tamización de Portadores Genéticos , Humanos , Cariotipificación , Masculino , Ratones , Mitocondrias/metabolismo , Proteínas de Transporte de Membrana Mitocondrial , Datos de Secuencia Molecular , Neurospora crassa/genética , Ornitina/metabolismo , Mutación Puntual , Saccharomyces cerevisiae/genética , Alineación de Secuencia , Eliminación de Secuencia , Homología de Secuencia de Aminoácido , Piel/metabolismo , Síndrome , Transfección
10.
Int J Cosmet Sci ; 35(5): 424-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23614537

RESUMEN

OBJECTIVE: This paper addresses the question of the coordination environment of copper (II) in hair. METHODS: The research is based on electron paramagnetic resonance (EPR), a spectroscopic technique that detects specifically paramagnetic molecules. Samples were investigated from various male and female subjects of different ages and races. RESULTS: The Cu(II) EPR signals seemed to be a combination of two components in widely differing relative proportions, although both have the relationship g(// )> g(⊥) > 2.0 expected for the unpaired electron in a d(x2-y2) orbital and are thus consistent with square planar or tetragonal symmetry for the Cu(II) ion. With a very few samples, the EPR spectra consisted of a single component, and high quality spectra from these samples are presented for use as standard reference results. In one type of complex, (14) N superhyperfine structure (shfs) was resolved and the spectrum corresponds to Cu coordination to mixed O- and N-containing functional groups, although the number of N atoms cannot be determined with certainty. No (14) N shfs was seen in the spectrum from the other type of complex, and its narrow linewidth excluded the possibility of any. Furthermore, the spectral parameters are inconsistent with coordination of the Cu to four O atoms, but consistent with some S coordinated to the Cu. Large variations between the relative proportions of the two Cu(II) forms were observed with a single healthy subject over a 5-year period, thus suggesting that they are determined by 'environmental' factors, possibly hair treatment processes, rather than being markers for the health of the subject. CONCLUSIONS: EPR spectroscopy is a convenient non-destructive method for determining the Cu coordination environment in hair, and could be used to monitor its response to various types of hair treatment.


Asunto(s)
Complejos de Coordinación/química , Cobre/química , Cabello/química , Espectroscopía de Resonancia por Spin del Electrón , Femenino , Humanos , Masculino
11.
Am J Case Rep ; 22: e933975, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34697281

RESUMEN

BACKGROUND Platypnea orthodeoxia syndrome (POS) presents with positional dyspnea and hypoxemia defined as arterial desaturation of at least 5% or a drop in PaO2 of at least 4 mmHg. Causes of POS include a variety of cardiopulmonary etiologies and has been reported in patients recovering from severe COVID-19 pneumonia. However, clinical presentation and outcomes in a patient with multiple interrelated mechanisms of shunting has not been documented. CASE REPORT An 85-year-old man hospitalized for hypertensive emergency and severe COVID-19 pneumonia was diagnosed with platypnea orthodeoxia on day 28 of illness. During his disease course, the patient required supplemental oxygen by high-flow nasal cannula but never required invasive mechanical ventilation. Chest imaging revealed evolving mixed consolidation and ground-glass opacities with a patchy and diffuse distribution, involving most of the left lung. Echocardiography was ordered to evaluate for intracardiac shunt, which revealed a patent foramen ovale. Closure of the patent foramen ovale was not pursued. Management included graded progression to standing and supplemental oxygen increases when upright. The patient was discharged to a skilled nursing facility and his positional oxygen requirement resolved on approximately day 78. CONCLUSIONS The present case highlights the multiple interrelated mechanisms of shunting in patients with COVID-related lung disease and a patent foramen ovale. Eight prior cases of POS after COVID-19 pneumonia have been reported to date but none with a known patent foramen ovale. In patients with persistent positional oxygen requirements at follow-up, quantifying shunt fraction over time through multiple modalities can guide treatment decisions.


Asunto(s)
COVID-19 , Foramen Oval Permeable , Anciano de 80 o más Años , Disnea/etiología , Foramen Oval Permeable/complicaciones , Foramen Oval Permeable/diagnóstico por imagen , Humanos , Hipoxia/etiología , Masculino , SARS-CoV-2
12.
Prenat Diagn ; 30(10): 970-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20812380

RESUMEN

OBJECTIVE: Barth Syndrome (BTHS) is an X-linked multisystem disorder (OMIM 302060) usually diagnosed in infancy and characterized by cardiac problems [dilated cardiomyopathy (DCM) ± endocardial fibroelastosis (EFE) ± left ventricular non-compaction (LVNC)], proximal myopathy, feeding problems, growth retardation, neutropenia, organic aciduria and variable respiratory chain abnormalities. We wished to determine whether BTHS had a significant impact on fetal and perinatal health in a large cohort of family groups originating from a defined region. METHOD: Case note review on 19 families originating from the UK and known to the Barth Syndrome Service of the Bristol Royal Hospital for Children. RESULTS: Details are presented on six kindreds (32%) with genetically and biochemically proven BTHS that demonstrate a wider phenotype including male fetal loss, stillbirth and severe neonatal illness or death. In these families, 9 males were stillborn and 14 died as neonates or infants but there were no losses of females. BTHS was definitively proven in five males with fetal onset of DCM ± hydrops/EFE/LVNC. CONCLUSION: These findings stress the importance of considering BTHS in the differential diagnosis of unexplained male hydrops, DCM, EFE, LVNC or pregnancy loss, as well as in neonates with hypoglycemia, lactic acidosis and idiopathic mitochondrial disease.


Asunto(s)
Síndrome de Barth/genética , Cardiomiopatía Dilatada/genética , Cromosomas Humanos X/genética , Muerte Fetal/genética , Enfermedades Fetales/genética , Mortinato/genética , Aciltransferasas , Síndrome de Barth/epidemiología , Síndrome de Barth/patología , Biomarcadores/sangre , Cardiolipinas/sangre , Cardiomiopatía Dilatada/epidemiología , Cardiomiopatía Dilatada/patología , Estudios de Cohortes , Fibroelastosis Endocárdica/epidemiología , Fibroelastosis Endocárdica/genética , Fibroelastosis Endocárdica/patología , Femenino , Muerte Fetal/epidemiología , Enfermedades Fetales/epidemiología , Enfermedades Fetales/patología , Humanos , No Compactación Aislada del Miocardio Ventricular/epidemiología , No Compactación Aislada del Miocardio Ventricular/genética , No Compactación Aislada del Miocardio Ventricular/patología , Lisofosfolípidos/sangre , Masculino , Linaje , Análisis de Secuencia de ADN , Factores Sexuales , Mortinato/epidemiología , Factores de Transcripción/genética , Reino Unido/epidemiología
13.
J Natl Med Assoc ; 102(4): 332-5, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20437740

RESUMEN

Vitamin D deficiency has been linked to fracture risk and chronic musculoskeletal pain. Adults with sickle cell disease have a high prevalence of low bone density and chronic pain with poorly defined etiologies. We recognized that vitamin D deficiency may represent a treatable etiology and sought to determine the prevalence of vitamin D deficiency in adults with sickle cell. We measured 25-hydroxy vitamin D levels in adults at 2 university-based sickle cell disease-management programs. Regression was performed in 142 patients to identify predictors of low vitamin D. Mean vitamin D levels were 9.0 ng/mL at Eastern Virginia Medical School and 12.8 ng/mL at University of Chicago; 139 of 142 (98%) had suboptimal levels (<30 ng/mL) and 85/142 (60%) were severely deficient (<10 ng/mL). Vitamin D level was not related to age, sex, hydroxyurea use, sickle cell type, or date of lab draw. Vitamin D deficiency was, therefore, nearly ubiquitous in our patient population, with a majority being severely deficient. Further studies are warranted to evaluate the effects of vitamin D repletion on clinical outcomes such as bone density, chronic musculoskeletal pain, and functional status. Clinicians caring for patients with sickle cell disease should be aware of and screen for this important clinical state.


Asunto(s)
Anemia de Células Falciformes/epidemiología , Deficiencia de Vitamina D/epidemiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Adulto Joven
14.
J Neurol Neurosurg Psychiatry ; 80(5): 524-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-18495738

RESUMEN

INTRODUCTION: Copper deficiency is an increasingly recognised cause of neurological impairment. This retrospective review highlights clinical and electrodiagnostic findings in patients diagnosed at our institution with copper deficiency. METHODS: Clinical, radiographic and electrodiagnostic findings were reviewed in patients with evidence of copper deficiency. Patients with other potential causes of myelopathy or neuropathy were excluded. RESULTS: The predominant clinical feature in all six patients was a sensory ataxia, resulting in marked gait unsteadiness. Nerve conduction studies and needle EMG were performed in all patients and revealed a mild to moderate distal, axonal, sensorimotor peripheral neuropathy. Median and tibial somatosensory evoked potentials were abnormal in all five patients in which it was performed, showing impaired conduction in central or proximal peripheral somatosensory pathways. CONCLUSIONS: This pattern of electrodiagnostic findings suggests that impairment in somatosensory pathways demonstrated by somatosensory evoked potential testing is the main cause of the sensory ataxia in patients with copper deficiency.


Asunto(s)
Cobre/deficiencia , Electrodiagnóstico , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Enfermedades de la Médula Espinal/diagnóstico , Anciano , Electromiografía , Potenciales Evocados Somatosensoriales/fisiología , Femenino , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Conducción Nerviosa/fisiología , Examen Neurológico , Enfermedades del Sistema Nervioso Periférico/patología , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Estudios Retrospectivos , Enfermedades de la Médula Espinal/patología , Enfermedades de la Médula Espinal/fisiopatología
15.
J Evol Biol ; 22(1): 143-51, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19120815

RESUMEN

The optimal division of resources into offspring size vs. number is one of the classic problems in life-history evolution. Importantly, models that take into account the discrete nature of resource division at low clutch sizes suggest that the variance in offspring size should decline with increasing clutch size according to an invariant relationship. We tested this prediction in 12 species of lizard with small clutch sizes. Contrary to expectations, not all species showed a negative relationship between variance in offspring size and clutch size, and the pattern significantly deviated from quantitative predictions in five of the 12 species. We suggest that the main limitation of current size-number models for small clutch sizes is that they rely on assumptions of hierarchical allocation strategies with independence between allocation decisions. Indeed, selection may favour alternative mechanisms of reproductive allocation that avoid suboptimal allocation imposed by the indivisible fraction at low clutch sizes.


Asunto(s)
Tamaño Corporal/fisiología , Tamaño de la Nidada/fisiología , Lagartos/fisiología , Animales , Femenino
16.
Science ; 207(4435): 1041-4, 1980 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-17759813

RESUMEN

Radiocarbon dates of volcanic activity suggest variations that appear to be related to climatic changes. Historical eruption records also show variations on the scale of years to centuries. These records can be combined with simple climatic models to estimate the impact of various volcanic activity levels. From this analysis it appears that climatic prediction in the range of 2 years to many decades requires broad-scale volcanic activity prediction. Statistical analysis of the volcanic record suggests that some predictability is possible.

18.
Biotechnol Annu Rev ; 14: 349-401, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18606370

RESUMEN

This chapter reviews the current status of research on investigations of the free radical chemistry of green tea and its constituent polyphenols (GTP). It is based on the use of electron paramagnetic resonance (EPR) spectroscopy, and also includes a section on practical aspects of the technique, which should be of value to readers who are unfamiliar with the detailed operation of EPR. The free radical chemistry of GTP is important, because many of their antioxidant functions involve reactions with O(2)-derived free radicals, and the products of such reactions are themselves generally free radicals. The stability of these products and their abilities to participate in subsequent reactions may have considerable bearing on their biological function. These are also discussed briefly along with the authors' views of future investigations which would appear to be valuable for this topic.


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/métodos , Flavonoides/química , Flavonoides/metabolismo , Fenoles/química , Fenoles/metabolismo , Especies Reactivas de Oxígeno/química , Especies Reactivas de Oxígeno/metabolismo , Té/química , Té/metabolismo , Radicales Libres/química , Radicales Libres/metabolismo , Polifenoles
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(5 Pt 2): 056216, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18643151

RESUMEN

We observe numerically, and explain analytically, a previously unknown phenomenon of quantum-Hall-like jumps in saturation spectral rigidity in the semiclassical spectrum of a modified Kepler problem as a function of the interval center. These jumps correspond to integer decreases of the radial winding numbers in classical periodic motion. We also observe and explain single-harmonic-dominated oscillations of the level number variance with the width of the energy interval. The level number variance becomes effectively zero for the interval widths defined by the frequency of the shortest periodic orbit. This signifies that there are virtually no variations from sample to sample in the number of levels on such intervals.

20.
Arch Dis Child Fetal Neonatal Ed ; 92(1): F59-61, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16877477

RESUMEN

Spontaneous neonatal arterial thrombosis is rare in the neonatal period. Four cases of neonatal arterial thrombosis presenting with suspected congenital heart disease are reported. The urgency for a correct diagnosis in this setting and the need for active treatment for a remediable condition are emphasised. These treatment options are discussed.


Asunto(s)
Aorta Torácica , Cardiopatías Congénitas/diagnóstico , Arteria Pulmonar , Trombosis/diagnóstico , Femenino , Atrios Cardíacos , Humanos , Recién Nacido , Masculino , Estudios Retrospectivos , Trombosis/terapia , Resultado del Tratamiento
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