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1.
Ann Bot ; 103(2): 221-35, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18708642

RESUMO

BACKGROUND AND AIMS: The lack of knowledge about key traits in field environments is a major constraint to germplasm improvement and crop management because waterlogging-prone environments are highly diverse and complex, and the mechanisms of tolerance to waterlogging include a large range of traits. A model is proposed that waterlogging tolerance is a product of tolerance to anaerobiosis and high microelement concentrations. This is further evaluated with the aim of prioritizing traits required for waterlogging tolerance of wheat in the field. METHODS: Waterlogging tolerance mechanisms of wheat are evaluated in a range of diverse environments through a review of past research in Australia and India; this includes selected soils and plant data, including plant growth under waterlogged and drained conditions in different environments. Measurements focus on changes in redox potential and concentrations of diverse elements in soils and plants during waterlogging. KEY RESULTS: (a) Waterlogging tolerance of wheat in one location often does not relate to another, and (b) element toxicities are often a major constraint in waterlogged environments. Important element toxicities in different soils during waterlogging include Mn, Fe, Na, Al and B. This is the first time that Al and B toxicities have been indicated for wheat in waterlogged soils in India. These results support and extend the well-known interactions of salinity/Na and waterlogging/hypoxia tolerance. CONCLUSIONS: Diverse element toxicities (or deficiencies) that are exacerbated during waterlogging are proposed as a major reason why waterlogging tolerance at one site is often not replicated at another. Recommendations for germplasm improvement for waterlogging tolerance include use of inductively coupled plasma analyses of soils and plants.


Assuntos
Adaptação Fisiológica , Elementos Químicos , Inundações , Solo , Triticum/crescimento & desenvolvimento , Triticum/fisiologia , Adaptação Fisiológica/efeitos dos fármacos , Aerobiose/efeitos dos fármacos , Alumínio/toxicidade , Anaerobiose/efeitos dos fármacos , Análise de Variância , Austrália , Biomassa , Meio Ambiente , Variação Genética , Índia , Modelos Biológicos , Oxirredução/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Triticum/efeitos dos fármacos , Triticum/genética
2.
J Chromatogr A ; 985(1-2): 303-12, 2003 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-12580498

RESUMO

A new technique has been developed for the quantitative analysis of pyridines in mainstream cigarette smoke using a GC-MS technique. For analysis, 10 cigarettes are smoked using conditions based on US Federal Trade Commission recommendations. The smoke is collected in a water trap and analyzed using a GC-MS technique. A standard or a fast GC separation can be applied for the analysis. The standard separation was followed by MS detection using selected ion monitoring (SIM) acquisition on a quadrupole instrument. The fast GC was followed by MS detection with total ion acquisition on a time-of-flight instrument. The levels of pyridine depend on the type of cigarette: for a full flavor cigarette pyridine is as high as 18.0 microg/cigarette (cig.). and for an ultra light cigarette is about 3.0 microg/cig. Substituted pyridines vary between 5.0 microg/cig. to 0.1 microg/cig. for a full flavor cigarette, and between 0.2 microg/cig. and a few ng/cig. for an ultra light cigarette. The reproducibility of the technique is very good, with less than 7-8% RSD in both separation procedures for most of the analyzed compounds.


Assuntos
Nicotiana/química , Piridinas/análise , Fumaça/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Reprodutibilidade dos Testes
3.
Indian J Psychiatry ; 42(2): 184-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21407933

RESUMO

The study was undertaken to find out correlation, if any, between severity of depression and suicidal intent communication and its relation to age, marital status, duration of iilness, previous admission in a psychiatric hospital in patients of depression diagnosed using criteria of ICD-IX category codes F31.3, F31.4, F31.5, F32 and F33. Sample consisted of 30 patients from the OPD of Agra Mansik Arogyashala. The Hamilton Rating Scale for depression was used to measure severity of depression and suicidal intent questionnaire was used to assess suicidal intent communication. A positive correlation between severity of depression, being married, being male, being employed, being ex-mental hospital patient, duration of illness being more than one month and age being less than or equal to 35 years was found. Further research in this area is required.

4.
Clin Auton Res ; 8(3): 173-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9651667

RESUMO

Representation of cardiovascular function has not been investigated in the human thalamus. In the rat, the insular cortex is the principal forebrain site of cardiovascular representation whose afferents originate from a circumscribed thalamic area (nucleus ventralis posterolateralis-parvicellular portion, VPLpc). We therefore evaluated 4481 thalamic cells for phasic cardiovascular activity using extracellular recording techniques in 60 unanesthetized patients undergoing neurosurgical procedures. We identified 26 cells with phasic activity strongly related to the cardiac cycle in 10 patients. These cells clustered within the ventrocaudal nucleus of the thalamus (the principal sensory nucleus analogous to the ventral posterior thalamic group in the rat and monkey) and were equally distributed between the right and left sides. The majority of these cells (17/26) showed peaks of phasic neuronal activity within 50 ms of the peak systolic pressure; 35% had peripheral cutaneous fields in areas to which cardiac pain is often referred. We suggest that these cells may be involved in the integration of afferent baroreceptor information; may possibly be concerned with the generation and/or processing of central cardiac pain in humans; and that their derangement may possibly contribute to the lethal cardiovascular disturbances which occur in fatal familial insomnia.


Assuntos
Sistema Cardiovascular/inervação , Tálamo/citologia , Tálamo/fisiologia , Potenciais de Ação/fisiologia , Adulto , Idoso , Mapeamento Encefálico , Estimulação Elétrica , Feminino , Humanos , Masculino , Microeletrodos , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/cirurgia , Vias Neurais/citologia , Vias Neurais/fisiologia , Tálamo/cirurgia , Tomografia Computadorizada por Raios X
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