Self-guiding light in layered nonlinear media.

We study the propagation of intense optical beams in layered Kerr media. With appropriate shapes, beams with a power close to the self-focusing threshold are shown to propagate over long distances as quasi-stationary waveguides in cubic media supporting a periodic nonlinear refractive index.

Bone marrow changes in anorexia nervosa are correlated with the amount of weight loss and not with other clinical findings.

The clinical history and biochemical and hematologic variables for 44 consecutive patients diagnosed with anorexia nervosa were recorded. Bone marrow aspirates and biopsy specimens were analyzed by standard morphologic procedures, and bone marrow adipocytes were studied morphometrically. The bone marrow of the 44 patients was classified as normal (5 cases [11%]), hypoplastic or aplastic (17 [39%]), with partial or focal gelatinous degeneration (13 [30%]), or with complete gelatinous degeneration of the bone marrow (GDBM; 9 [20%]).

[Abnormal changes in erythrocyte membrane proteins in hereditary spherocytosis and their relation to clinical and biological aspects of the disease].

Background: In the present paper we report a study of 20 patients with hereditary spherocytosis (HS) performed with the aim of provide further information on the electrophoretic abnormalities of red blood cell (RBC) membrane proteins and their putative relationship with the clinical, biological and genetic aspects of the disease.

Methods: General hematological parameters, reticulocyte count, osmotic fragility test and erythrocyte morphology analysis, were performed by routine procedures. Membrane proteins of erythrocyte were analyzed by SDS-polyacrylamide gradient gel electrophoresis (SDS-PAGE) using the Laemmli and Fairbanks methods.

Comparative study of spleen pathology in drug abusers with thrombocytopenia related to human immunodeficiency virus infection and in patients with idiopathic thrombocytopenic purpura. A morphometric, immunohistochemical, and ultrastructural study.

A morphometric and immunohistochemical study was performed to assess the spleen's alterations in patients with autoimmune thrombocytopenia and in drug abusers with thrombocytopenia (DAT) related to human immunodeficiency virus (HIV) infection. A total of 34 patients were included in the study: 20 DAT patients and 14 with idiopathic thrombocytopenic purpura (ITP). Twenty HIV-negative splenectomy patients without thrombocytopenia were included as controls.