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1.
J Microsc ; 289(2): 107-127, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36399637

RESUMO

The correlative imaging workflow is a method of combining information and data across modes (e.g. SEM, X-ray CT, FIB-SEM), scales (cm to nm) and dimensions (2D-3D-4D), providing a more holistic interpretation of the research question. Often, subsurface objects of interest (e.g. inclusions, pores, cracks, defects in multilayered samples) are identified from initial exploratory nondestructive 3D tomographic imaging (e.g. X-ray CT, XRM), and those objects need to be studied using additional techniques to obtain, for example, 2D chemical or crystallographic data. Consequently, an intermediate sample preparation step needs to be completed, where a targeted amount of sample surface material is removed, exposing and revealing the object of interest. At present, there is not one singular technique for removing varied thicknesses at high resolution and on a range of scales from cm to nm. Here, we review the manual and automated options currently available for targeted sample material removal, with a focus on those methods which are readily accessible in most laboratories. We summarise the approaches for manual grinding and polishing, automated grinding and polishing, microtome/ultramicrotome, and broad-beam ion milling (BBIM), with further review of other more specialist techniques including serial block face electron microscopy (SBF-SEM), and ion milling and laser approaches such as FIB-SEM, Xe plasma FIB-SEM, and femtosecond laser/LaserFIB. We also address factors which may influence the decision on a particular technique, including the composition, shape and size of the samples, sample mounting limitations, the amount of surface material to be removed, the accuracy and/or resolution of peripheral parts, the accuracy and/or resolution of the technique/instrumentation, and other more general factors such as accessibility to instrumentation, costs, and the time taken for experimentation. It is hoped that this study will provide researchers with a range of options for removal of specific amounts of sample surface material to reach subsurface objects of interest in both correlative and non-correlative workflows.


Assuntos
Técnicas Histológicas , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Fluxo de Trabalho , Imageamento Tridimensional/métodos , Técnicas Histológicas/métodos , Microtomia
2.
Sci Rep ; 8(1): 8190, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844342

RESUMO

The effect of a variety of metal-chlorides additions on the melting behavior and thermal stability of commercially available salts was investigated. Ternary salts comprised of KNO3, NaNO2, and NaNO3 were produced with additions of a variety of chlorides (KCl, LiCl, CaCl2, ZnCl2, NaCl and MgCl2). Thermogravimetric analysis and weight loss experiments showed that the quaternary salt containing a 5 wt% addition of LiCl and KCl led to an increase in short term thermal stability compared to the ternary control salts. These additions allowed the salts to remain stable up to a temperature of 630 °C. Long term weight loss experiments showed an upper stability increase of 50 °C. A 5 wt% LiCl addition resulted in a weight loss of only 25% after 30 hours in comparison to a 61% loss for control ternary salts. Calorimetry showed that LiCl additions allow partial melting at 80 °C, in comparison to the 142 °C of ternary salts. This drop in melting point, combined with increased stability, provided a molten working range increase of almost 100 °C in total, in comparison to the control ternary salts. XRD analysis showed the oxidation effect of decomposing salts and the additional phase created with LiCl additions to allow melting point changes to occur.

3.
Br J Dermatol ; 171(2): 376-87, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24702167

RESUMO

BACKGROUND: Excessive skin exposure to solar radiation damages proteins and DNA, ultimately leading to skin ageing and cancers. OBJECTIVES: To identify new ultraviolet B (UVB) target genes to understand the mechanisms behind the detrimental effects of UVB. METHODS: Organotypic, stratified cultures of rat keratinocytes were exposed to UVB and analysed using a genome-wide expression array, quantitative real-time polymerase chain reaction and histology. The most downregulated gene, rClca2, was further characterized in rat keratinocytes and mouse skin models. RESULTS: A single, 30 mJ cm(-2) dose of broadband UVB proved effective in the organotypic epidermal culture. The expression of 627 genes was changed 24 h postirradiation. In silico analysis of the data indicated activation of DNA repair, metabolism, cell cycle control and amino acid metabolism, but only limited inflammation under these conditions. We selected for further investigation the most downregulated gene, rClca2, previously suggested to regulate keratinocyte differentiation and adhesion, and found that UVB caused a long-lasting downregulation in its expression. Both the rClca2 full-length isoform (expressed in the differentiating cells) and the truncated isoform (expressed in the basal layers) were reduced by UVB. Immunohistochemistry of mouse skin samples with isoform-specific antibodies showed a similar, epidermal differentiation-related pattern. In mouse specimens exposed to chronic ultraviolet radiation (UVR) the staining intensities were reduced and the differentiation-related isoform was disturbed in the hyperplastic and carcinomatous areas induced by UVR. CONCLUSIONS: The data show that rClca2 is a novel UVB target gene and suggest that it might play a role in epidermal differentiation and UV-dependent skin malignancies.


Assuntos
Canais de Cloreto/efeitos da radiação , Epiderme/efeitos da radiação , Raios Ultravioleta , Animais , Diferenciação Celular/efeitos da radiação , Células Cultivadas , Canais de Cloreto/metabolismo , Relação Dose-Resposta à Radiação , Regulação para Baixo , Células Epidérmicas , Epiderme/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Queratinócitos/efeitos da radiação , Camundongos , RNA/metabolismo , Ratos , Fatores de Transcrição/efeitos da radiação
6.
South Med J ; 92(5): 477-80, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10342892

RESUMO

BACKGROUND: Bone marrow aspirate and biopsy is universally recognized as being painful. Few descriptions of effective analgesia or premedication for this procedure exist. In this study, we assessed an oral narcotic and benzodiazepine combination in controlling pain associated with bone marrow examination. METHODS: Twenty-four consecutive ambulatory, adult patients referred for bone marrow examination received oral medications 90 minutes before the scheduled procedure. Patients reported perceived pain, using both Likert numerical and "Faces Pain Rating Scale," immediately after bone marrow examination and within 1 week after the procedure. Physicians' and nurses' evaluations of patient tolerance and the patients' memories of the aspiration and biopsy were recorded. RESULTS: Two thirds (66%) of the respondents reported none or only mild pain (3 or less on a scale of 1 to 10). Memory of the procedure was vague or nonexistent in approximately half of the patients. There were no complications of biopsies or premedication. CONCLUSIONS: Premedication with oral narcotic and benzodiazepine is effective in preventing or lessening pain associated with bone marrow examination in adults. Premedication induces amnesia for some or most of the procedure in about half of the patients.


Assuntos
Benzodiazepinas/administração & dosagem , Exame de Medula Óssea/efeitos adversos , Entorpecentes/administração & dosagem , Dor/tratamento farmacológico , Administração Oral , Adulto , Analgesia/métodos , Quimioterapia Combinada , Feminino , Humanos , Hidromorfona/administração & dosagem , Lorazepam/administração & dosagem , Masculino , Pessoa de Meia-Idade , Medição da Dor , Limiar da Dor , Pré-Medicação/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-1821228

RESUMO

The records of 34 patients who showed evidence of emotional deterioration 6 months or more following traumatic brain injury were compared with a group of patients matched for severity of initial neuropsychiatric impairment who did not show deterioration. The deterioration group was more likely to have been involved in assaults and less likely to have been involved in a motor vehicle accident than the improvement group. The deterioration group was also more likely to have a prior history of alcohol abuse and to have sustained a skull fracture with left parietal lobe injury than the improvement group. Agitation, hostility, apathy, lability of mood, emotional withdrawal, and depression were the symptoms most likely to worsen over time. This deterioration may have been due to premorbid personality characteristics or to the nature of long-term neuronal response to injury.


Assuntos
Sintomas Afetivos/diagnóstico , Dano Encefálico Crônico/diagnóstico , Lesões Encefálicas/complicações , Transtornos Cognitivos/diagnóstico , Transtornos Neurocognitivos/diagnóstico , Testes Neuropsicológicos , Adulto , Sintomas Afetivos/fisiopatologia , Sintomas Afetivos/psicologia , Encéfalo/fisiopatologia , Dano Encefálico Crônico/fisiopatologia , Dano Encefálico Crônico/psicologia , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/psicologia , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/psicologia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Transtornos Neurocognitivos/fisiopatologia , Transtornos Neurocognitivos/psicologia , Exame Neurológico
8.
Am J Public Health ; 74(6): 602-4, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6721017

RESUMO

In November 1981, an outbreak of waterborne giardiasis occurred at a popular ski resort in Colorado. Stratification of illness by consumption of municipal tap water showed a striking dose-response, with an attack rate of 42 per cent among persons who drank six or more glasses of water per day. Filtered water samples revealed Giardia cysts in specimens both before and after treatment, and several deficiencies were found in the water treatment facility. Residents who had lived in the area greater than 2 years had a lower attack rate for illness than short-term residents.


Assuntos
Surtos de Doenças/epidemiologia , Giardíase/epidemiologia , Abastecimento de Água/análise , Animais , Colorado , Ingestão de Líquidos , Giardia/isolamento & purificação , Giardíase/imunologia , Giardíase/parasitologia , Humanos
9.
Dev Med Child Neurol ; 25(6): 735-7, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6653906

RESUMO

It is a well-established fact that 20 to 40 per cent of patients in residential institutions for the retarded have seizures and take anticonvulsants. Most patients have quiescent seizure disorders and can manage well on monotherapy. In this study, 78 per cent of the patients remained seizure-free after switching from multiple-drug regimens to monotherapy.


Assuntos
Anticonvulsivantes/administração & dosagem , Epilepsia/tratamento farmacológico , Deficiência Intelectual/tratamento farmacológico , Adolescente , Adulto , Carbamazepina/administração & dosagem , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenobarbital/administração & dosagem , Fenitoína/administração & dosagem , Primidona/administração & dosagem
11.
Am J Drug Alcohol Abuse ; 5(2): 211-20, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-747175

RESUMO

The construction and research application of the Alcadd are reviewed. Interscale relationships and age and education effects in a large alcoholic inpatient population are examined.


Assuntos
Alcoolismo/diagnóstico , Autoavaliação (Psicologia) , Inquéritos e Questionários , Adulto , Fatores Etários , Idoso , Escolaridade , Estudos de Avaliação como Assunto , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa
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