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71.
72.
Oli I. Traustason Steven E. Feldon Jay E. Leemaster John M. Weiner 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1988,226(3):206-212
Visual fields of patients with anterior ischemic optic neuropathy (AION) were classified according to quantitative criteria, using the Octopus perimeter. Although a significant altitudinal pattern of field loss was found in 55% of perimetric examinations, the "spared" hemifields routinely showed some loss of sensitivity. This finding, along with the diffuse loss of sensitivity in a high percentage of visual fields, indicates more extensive involvement of the circulation of the anterior optic nerve head than has previously been suggested. Furthermore, patients with diabetes mellitus alone were found to have a statistically separable pattern of visual field loss. The pathophysiologic implications of the visual fields in AION and their relationship to the clinical findings were investigated. 相似文献
73.
Summary Unusual inclusions with some of the features of reducing bodies were encountered in the skeletal muscle biopsy of a 2.5-year-old boy with childhoodonset acid maltase deficiency. The biopsy revealed a vacuolar myopathy with lysosomal storage of glycogen and eosinophilic refractile inclusions in myofibers, which appeared dark blue with the menadione-nitroblue tetrazolium reaction. The significance of the association of inclusions with reducing properties in the setting of acid maltase deficiency is discussed. 相似文献
74.
Current concepts in inguinal hernia in infants and children 总被引:4,自引:0,他引:4
Jay L. Grosfeld M.D. 《World journal of surgery》1989,13(5):506-515
Trends are changing in the management of infants and children with indirect inguinal hernias. Advances in neonatal intensive care have resulted in the survival of many small premature infants who have a high incidence of inguinal hernia. The rate of incarceration, strangulation, and gonadal infarction in these babies is twice that of the general pediatric age group. Respiratory immaturity, apnea, bradycardia, and associated neonatal conditions require special management at the time of hernia repair, usually performed just before discharge from the neonatal intensive care unit. New information concerning volume loss and depletion of germ cells beginning at 6 months of age in boys with undescended testes has stimulated the performance of orchiopexy when the patient is 1 year of age. More than 90% of boys with cryptorchid testes at the age of 1 year have an associated hernia that requires concomitant repair at the time of orchiopexy. The use of the peritoneal cavity for fluid absorptive purposes in hydrocephalus treated by venticuloperitoneal shunts or of peritoneal dialysis for renal failure and metabolic diseases such as hyperammonemia and lactic acidosis causes increased intraabdominal pressure and results in the appearance of a previously unrecognized hernia. Recognition of these and other conditions associated with a high incidence of hernial occurrence should allow early diagnosis and treatment before the development of complications. Most elective repairs of hernias are safely performed in the outpatient setting; however, some infants and children with concurrent illnesses are best managed in a morning admissions program, in which hospital admission occurs postoperatively.
Resumen Este artículo se refiere a las tendencias en el manejo de lactantes y niños con hernias inguinales indirectas. Los avances logrados en el cuidado intensivo neonatal han resultado en la supervivencia de muchos pequeños prematuros, quienes exhiben una elevada incidencia de hernia inguinal. La tasa de incarceración, estrangulación, e infarto gonadal en estos pacientes es dos veces la de la población pediátrica general. La inmadurez respiratoria, apnea, bradicardia, y otras condiciones neonatales asociadas requieren un manejo especial con ocasión de la reparación herniaria, la cual generalmente se realiza inmediatamente antes de la salida de la unidad de cuidado intensivo neonatal. Nuevos conocimientos sobre pérdida de volumen y depleción de las células germinales, lo cual comienza a los 6 meses de edad en niños con testículos no descendidos, ha estimulado la realización de orquidopexia cuando el paciente llegue a la edad de un ano. Más del 90% de los niños con testículos criptorquídicos a la edad de un año tienen una hernia asociada que requiere reparación concomitante con la orquidopexia. El uso de la cavidad peritoneal para efectos de absorción de fluidos en el caso de hidrocéfalos tratados con la implantación de sistemas valvulares ventriculoperitoneales, o de diálisis peritoneal para falla renal y enfermedades metabólicas tales como hiperamonemia o acidosis láctica, causa un aumento en la presión intraabdominal y resulta en la aparición de una hernia previamente inaparente. La identificación de estas y otras condiciones asociadas con una elevada incidencia de hernia debe hacer posible el diagnóstico y tratamiento tempranos, antes de que se presenten complicaciones. La mayoría de las reparaciones herniarias pueden ser realizadas en forma adecuada como procedimientos ambulatorios. Sin embargo, algunos infantes y niños con enfermedades concurrentes pueden ser mejor manejados en un programa de admisión matinal, en el cual la hospitalización se produce en el postoperatorio.
Résumé Le traitement des hernies inguinales obliques externes chez le bébé et l'enfant évolue. Les progrès accomplis dans les soins intensifs des nouveau-nés ont permis la survie d'un plus grand nombre d'enfants prématurés qui présentent une fréquence plus importante de hernies inguinales. Le taux d'engouement, d'étranglement, et d'ischémie gonadale chez cette population est deux fois celui de la population pédiatrique générale. Le développement respiratoire inachevé, l'apnée, la bradycardie, et d'autres conditions néonatales associées sont autant de facteurs qui nécessitent le travail d'une équipe spécialisée au moment du traitement de la hernie qui se situe juste avant la sortie de l'unité de soins intensifs. Certaines études ayant montré une perte de volume et une déplétion de cellules germinales à partir de l'âge de 6 mois chez le garçon avec une ectopie testiculaire, on préconise une orchidopexie tôt, à l'âge d'un an. Plus de 90% de ces enfants présentent une hernie associée qui doit être réparée en même temps. L'utilisation de la cavité péritonéale pour dériver l'hydrocéphalie par shunt ventriculopéritonéal ou pour dialyse péritonéale en cas d'insuffisance rénale ou autres maladies métaboliques comme l'hyperammonémie et l'acidose lactique sont des causes d'hyperpression intra-abdominale avec augmentation du nombre de cas de hernies jusqu'alors méconnues. Une meilleure connaissance de ces conditions propices à augmenter le nombre de hernies symptomatiques devrait permettre d'en faire le diagnostic plus tôt et de les traiter avant l'apparition des complications. La plupart des hernies non compliquées sont traitées sans hospitalisation. Cependant, quelques bébés et enfants ayant d'autres maladies concomitantes sont mieux traités avec un programme d'hospitalisation de jour, c'est-à-dire que l'enfant est hospitalisé pendant 24 heures après son opération.相似文献
75.
Lung surfactant gelation induced by epithelial cells exposed to air pollution or oxidative stress 总被引:1,自引:0,他引:1
Anseth JW Goffin AJ Fuller GG Ghio AJ Kao PN Upadhyay D 《American journal of respiratory cell and molecular biology》2005,33(2):161-168
Lung surfactant lowers surface tension and adjusts interfacial rheology to facilitate breathing. A novel instrument, the interfacial stress rheometer (ISR), uses an oscillating magnetic needle to measure the shear viscosity and elasticity of a surfactant monolayer at the air-water interface. The ISR reveals that calf lung surfactant, Infasurf, exhibits remarkable fluidity, even when exposed to air pollution residual oil fly ash (ROFA), hydrogen peroxide (H2O2), or conditioned media from resting A549 alveolar epithelial cells (AEC). However, when Infasurf is exposed to a subphase of the soluble fraction of ROFA- or H2O2-treated AEC conditioned media, there is a prominent increase in surfactant elasticity and viscosity, representing two-dimensional gelation. Surfactant gelation is decreased when ROFA-AEC are pretreated with inhibitors of cellular reactive oxygen species (ROS), or with a mitochondrial anion channel inhibitor, as well as when A549-rho0 cells that lack mitochondrial DNA and functional electron transport are investigated. These results implicate both mitochondrial and nonmitochondrial ROS generation in ROFA-AEC-induced surfactant gelation. A549 cells treated with H2O2 demonstrate a dose-dependent increase in lung surfactant gelation. The ISR is a unique and sensitive instrument to characterize surfactant gelation induced by oxidatively stressed AEC. 相似文献
76.
77.
Cyclin alterations in giant cell tumor of bone. 总被引:3,自引:0,他引:3
Adel Kauzman Shu Qiu Li Grace Bradley Robert S Bell Jay S Wunder Rita Kandel 《Modern pathology》2003,16(3):210-218
Cyclins play an important role in regulating the passage of dividing cells through critical checkpoints in the cell cycle. Because alterations of several cyclins, especially cyclin D1, have been implicated in the development of many human neoplasms, we examined 32 cases of giant cell tumor of long bones for cyclin D1 gene amplification and protein overexpression using differential polymerase chain reaction and immunohistochemistry, respectively. In addition, the expression of cyclin D3, cyclin B1, and the proliferation-associated antigen Ki-67 (MIB-1) was assessed immunohistochemically. Low-level cyclin D1 gene amplification was detected in 61% of giant cell tumor cases. All tumors showed cyclin D1, cyclin D3, cyclin B1, and Ki-67 (MIB-1) staining; however, the distribution was very characteristic. Cyclin D1 protein expression was seen predominantly in the nuclei of the giant cells, with occasional mononuclear cells staining. There was no correlation between cyclin D1 gene amplification and protein overexpression. Cyclin D3 staining showed a similar distribution, with 88% of cases showing protein overexpression. Cyclin D1 and/or D3 staining in the giant cells was never associated with staining for either cyclin B1 or Ki-67 (MIB-1), as the expression of the latter two proteins was restricted to the mononuclear cells. Cyclin B1 overexpression was seen in 44% of cases. Ki-67 (MIB-1) staining was present in all cases, and between 10 to 50% of the mononuclear cells were positive. These results suggest that alterations in cyclin D1 and/or D3 might play a role in the pathogenesis of giant cell tumor of bone. 相似文献
78.
The rate of HIV-1 disease progression is influenced by several factors that include pathogen and host genetic variations and the quality of antiviral immune responses. The CD8+ cell non-cytotoxic antiviral response (CNAR) substantially suppresses HIV replication in CD4+ cells and is positively associated with an asymptomatic clinical state. Traditionally, the measurement of CNAR has required several culture procedures and costly reagents. Here we report the development and validation of a screening assay for detection of CNAR that accurately identifies individuals benefiting from this response. Use of the CNAR screening assay should facilitate the evaluation of this important immune parameter in studies of HIV pathogenesis, resistance to infection, and vaccine development. 相似文献
79.
M S Bartlett J A Fishman S F Queener M M Durkin M A Jay J W Smith 《Journal of clinical microbiology》1988,26(6):1100-1102
Rats free of latent Pneumocystis carinii organisms were immunosuppressed with adrenal corticosteroids and transtracheally injected with P. carinii. These animals subsequently developed P. carinii pneumonia. Infection was accomplished by using organisms from infected rat lung or from culture. Diffuse infection was produced with no significant differences in the numbers of organisms found in various lobes of the lungs. Infections progressed over time so that by 6 weeks postinoculation all animals were heavily infected. Infection by transtracheal injection has three advantages over current models. First, transtracheal injection provides a reliable model which is not dependent on naturally occurring latent Pneumocystis infection. Second, transtracheal injection allows the perpetuation of specific Pneumocystis strains. Third, transtracheal injection is a more rapid and economical means of producing severe Pneumocystis pneumonia. 相似文献
80.