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1.
Phys Rev E Stat Nonlin Soft Matter Phys ; 67(2 Pt 2): 026602, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12636836

RESUMEN

The Wigner-Moyal equation for the Wigner distribution of a partially incoherent optical wave field propagating in dispersive and nonlinear media has been generalized to include the effects of both arbitrary order of dispersion and arbitrary nonlinearity. The theory predicts partial incoherence to enhance the pulse broadening during linear wave pulse propagation. Furthermore, an application of the theory to the modulational instability of constant amplitude waves shows how higher-order dispersion affects the instability growth rate.

2.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(5 Pt 2): 056602, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12059726

RESUMEN

An investigation is made of the formation of a single soliton, or a pair of solitons, from initially nontransform limited pulses in a nonlinear Kerr medium having anomalous dispersion. A qualitative physical explanation is given for the formation of soliton pairs. Approximate solutions for the amplitudes and the velocities of the generated solitons are established and corroborated by numerical solutions of the Zakharov-Shabat eigenvalue problem.

5.
Pediatr Pathol ; 2(1): 1-24, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6542208

RESUMEN

The renal lesions of 15 children with tubulointerstitial diseases (TID), originally diagnosed as Fanconi's familial nephronophthisis (FFN), medullary cyst disease (MCD), or antitubular basement membrane (TBM) antibody disease were studied by light, electron, and immunofluorescence microscopy and by peroxidase-antiperoxidase stain for IgG. Kidneys originally considered in all three categories showed similar pathologic findings, with periglomerular fibrosis, interstitial fibrosis and infiltration, TBM thickening, and glomerulopathy. The data suggest that MCD and FFN are not synonyms, but that FFN can lead to medullary cystic disease, as can other tubulointerstitial diseases. Anti-TBM disease appears to be a more frequent cause of TID than is usually recognized. Glomerular involvement in TID may be due to deposition of anti-TBM antibody/TBM antigen complexes.


Asunto(s)
Enfermedades Autoinmunes/patología , Síndrome de Fanconi/patología , Enfermedades Renales Quísticas/patología , Nefritis Intersticial/patología , Membrana Basal/inmunología , Niño , Preescolar , Humanos , Lactante , Túbulos Renales/inmunología , Nefritis Intersticial/etiología , Nefritis Intersticial/inmunología
6.
Phys Rev Lett ; 90(1): 013901, 2003 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-12570610

RESUMEN

The classical problem of determining the solitons generated from symmetric real initial conditions in the nonlinear Schrödinger equation is revisited. The corresponding Zakharov-Shabat scattering problem is solved for real and symmetric double-humped rectangular initial pulse forms. It is found that such real symmetric pulses may generate eigenvalues with nonzero real parts corresponding to separating soliton pulse pairs. Moreover, it is found that the classical formula relating the number of eigenvalues to the area of the pulse is not always correct.

7.
Z Exp Chir ; 12(3): 138-45, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-43627

RESUMEN

In the presented series of experiments, stroma-free hemoglobin solution (SFHS) was used as a perfusate for extracorporeal perfusion of kidneys and for exchange transfusion. It was shown that SFHS was adequatly oxygenated both as perfusate during the extracorporal perfusion and in the lungs after the blood exchange. Furthermore, there was provided evidence that oxygen was being transported and released in the tissues. Histologic examination of the kidneys demonstrated hemoglobin casts in the glomerules. Most of them were seen after extracorporal perfusion of isolated kidneys, less frequently after perfusion in situ and few casts were present after exchange transfusion. The cause of these depositions may be small remnants of stroma in the preparation. Furthermore it is possible, that at the beginning of the extracorporal perfusion of the kidneys the urine pH was below 6 and then a hemoglobin casts formation could occur. There were essential no changes in urine pH in the course of blood exchange. In this group were only few casts present in the kidneys.


Asunto(s)
Hemoglobinas , Animales , Sistema Libre de Células , Perros , Recambio Total de Sangre , Concentración de Iones de Hidrógeno , Consumo de Oxígeno , Diálisis Renal , Orina/análisis
8.
Artículo en Inglés | MEDLINE | ID: mdl-6719970

RESUMEN

In the continuing search for promoting the bio-pharmacological characteristics of an excellent oxygen carrier, the Stroma-free Haemoglobin Solution (SFHS), in the presented work, the authors were investigating the composition changes of SFHS infused to dogs. In 10 mongrel dogs a total exchange of the circulating blood was done for replacing it with SFHS. For the observing the physico-chemical changes in circulating and excreted fluids electron spectroscopy was used in view of good spectral characteristics of haemoglobin, and a high sensitivity of this method to changes taking place in the analyzed molecule. Comparing the spectral curves characterizing the solution used for exchange transfusion with the spectral curves obtained from circulating SFHS samples and haemoglobin excreted in the urine, and from the ascites, during the 6 hours course of the experiment, no essential structural changes were observed in the hemin molecule, in the visible range.


Asunto(s)
Recambio Total de Sangre , Hemoglobinas/farmacología , Riñón/fisiología , Animales , Perros , Hemoglobinuria/orina , Concentración de Iones de Hidrógeno , Riñón/efectos de los fármacos , Potasio/orina , Sodio/orina , Espectrofotometría Ultravioleta
9.
Pediatr Pathol ; 2(4): 441-55, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6535998

RESUMEN

The renal lesion of congenital hepatic fibrosis (CHF = Blyth and Ockenden's juvenile polycystic disease of liver and kidneys) was analyzed from 6 specimens from patients aged 3 3/12 to 19 3/12 years and compared with that of 5 patients with infantile polycystic disease (IPCD) aged 6 months to 14 4/12 years. Pathologic, microdissection, injection, and morphometric studies show that the predominantly medullary cystic lesion of CHF shows different distribution in medullary, cortico-medullary, and cortical zones of kidney from the lesion of IPCD, and shows a different time course, from early life to renal insufficiency, from that of IPCD. The renal cysts in CHF affect deep or central collecting tubules, in contrast to the involvement of more peripheral orders of collecting tubules in IPCD. Papillary pore counts, performed for 1 patient, gave significantly low values, in contrast to normal values reported for IPCD. The findings support the previously published conclusion, based on differences in the hepatic lesions of the two conditions, that CHF and IPCD are difference diseases, rather than different permissible manifestations of a single disease.


Asunto(s)
Enfermedades Renales/etiología , Hepatopatías/congénito , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Enfermedades Renales/patología , Hepatopatías/complicaciones , Hepatopatías/patología , Masculino , Enfermedades Renales Poliquísticas/patología
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