Solution of chlorophyll a in liquid crystals mixture (MBBA + EBBA) was investigated. Chl molecules are in LC in low electric field oriented. They can be divided into two groups: one strongly interacting with LC and subjected to reorientation by the electric field, and another weakly interacting with the solvent and insensitive to the voltage applied. The emission spectrum of the first type of chlorophyll is strongly perturbed. At higher voltages, the pigment molecules orientation in the plane of the electrode is another. Pigment absorption and emission anisotropy provides information about the reorientation of LC molecules. Even at high (10(-3)M) Chl concentration and regular pigment array, the interaction between the pigment and solvent exceeds pigment-pigment interaction because the solvent appears to have a stronger influence on the Chl spectrum.

Benzylidene Compounds↗

PubMed1977

Cardiology. Reassessment of left bundle-branch block.

In a population of patients who seek medical attention because of possible cardiac symptoms and are found to have left bundle-branch block, the vast majority have obvious cardiac disease, usually atherosclerotic or hypertensive. The prognosis in this group is poor and is a function of the underlying heart disease and not the conduction defect per se. The situation is distinctly different in a population of asymptomatic subjects whose conduction defect is discovered during routine electrocardiographic screening. In some of these individuals the conduction defect reflects previously unrecognized cardiac disease, but the majority have no other evidence of cardiovascular abnormality and approximately two thirds continue to do well over a relatively long follow-up period. It seems reasonable to reassure such patients regarding their prognosis, while at the same time maintaining careful follow-up. In situations where there is an important need to know for certain whether an individual has underlying cardiac disease, cardiac catheterization is indicated and should include coronary arteriography and hemodynamic measurements during exercise.

Adult↗

PubMed1975

Letter: Halitosis from isosorbide dinitrate.

Explore the source record for details and available documents.

Halitosis↗