RESUMO
Commissariat à l'Énergie Atomique et aux Énergies Alternatives has developed the ARGOS X-ray framing camera to perform two-dimensional, high-timing resolution imaging of an imploding target on the French high-power laser facility Laser MegaJoule. The main features of this camera are: a microchannel plate gated X-ray detector, a spring-loaded CCD camera that maintains proximity focus in any orientation, and electronics packages that provide remotely-selectable high-voltages to modify the exposure-time of the camera. These components are integrated into an "air-box" that protects them from the harsh environmental conditions. A miniaturized X-ray generator is also part of the device for in situ self-testing purposes.
RESUMO
This article proposes an innovative multichannel optically stimulated luminescence (OSL) dosemeter for on-line in vivo dose verification in radiation therapy. OSL fibre sensors incorporating small Al(2)O(3):C fibre crystals (TLD(500)) have been tested with an X-ray generator. A reproducible readout procedure should reduce the fading-induced uncertainty ( approximately - 1% per decade). OSL readouts are temperature-dependent [ approximately 0.3% K(-1) when OSL stimulation is performed at the same temperature as irradiation; approximately 0.16% K(-1) after thermalisation (20 degrees C)]. Sensor calibration and depth-dose measurements with electron beams have been performed with a Saturne 43 linear accelerator in reference conditions at CEA-LNHB (ionising radiation reference laboratory in France). Predosed OSL sensors show a good repeatability in multichannel operation and independence versus electron energy in the range (9, 18 MeV). The difference between absorbed doses measured by OSL and an ionisation chamber were within +/-0.9% (for a dose of about 1 Gy) despite a sublinear calibration curve.
Assuntos
Óxido de Alumínio , Carbono , Dosagem Radioterapêutica , Radioterapia , Dosimetria Termoluminescente/instrumentação , Algoritmos , Calibragem , Humanos , Método de Monte Carlo , Aceleradores de Partículas , Temperatura , IncertezaAssuntos
Adoção , Criança , Desenvolvimento Infantil , Proteção da Criança , Humanos , Internacionalidade , Pediatria , QuebequeRESUMO
Intracranial complications from otitis media can be quite devastating to the patient if an early diagnosis is not made. Patients may develop meningitis, venous sinus thrombosis or cranial nerve palsies, as well as intracranial abscess. The presenting features in such cases may be subtle and include headache, nausea, vomiting, personality changes and signs of increased intracranial pressure as well as focal neurological deficits. A case of intracranial brain abscess is presented in a patient with a history of chronic otitis media with cholesteatoma. Delay in the diagnosis of intracranial complications of otitis media can lead to improper treatment with increased morbidity and mortality. The etiology and treatment of complications affecting the CNS is discussed.
Assuntos
Abscesso Encefálico/diagnóstico por imagem , Otite Média/complicações , Abscesso Encefálico/etiologia , Criança , Colesteatoma/complicações , Doença Crônica , Erros de Diagnóstico , Otopatias/complicações , Humanos , Masculino , Mastoidite/diagnóstico por imagem , Mastoidite/etiologia , Osso Temporal/diagnóstico por imagem , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
The results of toxicological screening of body fluids (urine, blood and gastric lavage) from pediatric patients were analyzed for the period January 1985 - December 1988. Of the 119 cases, approximately one half were positive for at least one foreign substance. In about one fifth of the cases, multiple substances were detected. The most commonly implicated drugs were those acting on the central nervous system including the barbiturates, tricyclic antidepressants, phenothiazines, benzodiazepines and carbamazepine.
Assuntos
Intoxicação/epidemiologia , Análise Química do Sangue , Pré-Escolar , Cromatografia em Camada Fina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Lavagem Gástrica , Conteúdo Gastrointestinal/química , Humanos , Lactente , Kuweit/epidemiologia , Masculino , Intoxicação/diagnóstico , Estudos Retrospectivos , Urina/químicaRESUMO
Between September 1981 and March 1987, 92 episodes of bacterial meningitis in 90 children were treated in three major hospitals in Kuwait. The diagnosis was bacteriologically confirmed in 80 (87%). Haemophilus influenzae was the most common aetiological organism and accounted for 42 episodes (45.6%) followed by Streptococcus pneumoniae in 21 (22.8%) and Neisseria meningitidis in only three (3.3%). Bacterial meningitis occurred in 53 children (57.6%) below the age of 1 year and in 81 (88%) below 5 years. The overall case fatality rate was 5.4% and ten children (9%) had severe neurological sequelae of their disease. Sequelae were more common following pneumococcal meningitis (28%) than after Haemophilus (7%). All 12 children with unknown pathogen recovered completely.
Assuntos
Meningite por Haemophilus/epidemiologia , Meningite Meningocócica/epidemiologia , Meningite Pneumocócica/epidemiologia , Fatores Etários , Criança , Pré-Escolar , Surdez/etiologia , Feminino , Humanos , Hidrocefalia/etiologia , Incidência , Lactente , Recém-Nascido , Kuweit/epidemiologia , Masculino , Meningite por Haemophilus/complicações , Meningite por Haemophilus/mortalidade , Meningite Meningocócica/complicações , Meningite Meningocócica/mortalidade , Meningite Pneumocócica/complicações , Meningite Pneumocócica/mortalidade , Estações do Ano , Convulsões/etiologia , Derrame Subdural/etiologiaRESUMO
Kenny-Caffey Syndrome is a rare syndrome characterized by growth retardation, uniformly small slender long bones with medullary stenosis, thickened cortex of the long bones, hypocalcemia possibly with tetany at an early age, hyperphosphatemia, ocular abnormalities, and normal intelligence. We report a child with Kenny-Caffey Syndrome and idiopathic hypoparathyroidism and present a review of the literature summarizing the reported cases of this rare syndrome.
Assuntos
Transtornos do Crescimento , Pré-Escolar , Oftalmopatias/terapia , Feminino , Transtornos do Crescimento/diagnóstico por imagem , Transtornos do Crescimento/terapia , Humanos , Hipocalcemia/terapia , Radiografia , SíndromeRESUMO
Bleomycin inhibits cellular RNA synthesis and the inhibition is nonspecific. The ratio of polyadenylate- [poly(A)] containing RNA to non-poly(A)-containing RNA in the drug-treated human lymphocytic cells, line Wil2, was the same as that in untreated cells. Poly(A) RNA isolated from untreated cells was used as a template for reverse transcriptase to synthesize complementary DNA, which was then used as a probe to assay the sequence diversity of poly(A)RNA's from treated and untreated cells. It was found that essentially all of the poly(A) RNA's in the untreated cells were also present in the treated cells. The effect of bleomycin on the biological activity of messenger RNA (mRNA) was tested with globin mRNA in a wheat germ embryo translation system. Although bleomycin inhibited protein synthesis at high concentrations, the inhibition was not due to a modification of mRNA. This was evidenced by the fact that no decrease in the ability of mRNA to function in the test system was found when globin mRNA was pretreated with high concentrations of bleomycin followed by removal of the drug.