RESUMO
This report details correlated electrical, mechanical and magnetic behaviour in BiFeO(3) ceramics doped with 10% Ln (Ln = Sm, Nd) ions on the Bi, or perovskite A, site and synthesized by a sol-gel method. The ceramics exhibit bulk piezoelectric and ferroelectric properties and clear ferroelectric domain patterns through piezoresponse force microscopy. Resonant ultrasound spectroscopy, dielectric spectroscopy and magnetometry studies show correlated magnetoelectromechanical behaviour and the existence of weak ferromagnetism for both compositions. An anomaly with simultaneous mechanical and magnetic signatures is discovered in both materials near room temperature, while previously reported transitions and anomalies are found to exhibit electro- and/or magnetomechanical coupling. Magnetism is significantly enhanced in the Sm doped sample, which is a promising multiferroic material.
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The family of two-dimensional magnetic materials M(II)PS(3) where M = Mn, Fe, Ni, Mg, Zn, etc shows a wide range of fascinating magnetic behaviour. It also shows potentially useful chemical properties including intercalation of nonlinear optical molecules and lithium ions. These properties are due to a crystal structure in which the ab planes are well-ordered in the plane but poorly correlated along c. Here, the short-range ordering is modelled in NiPS(3) and Ni(1 - x)Mg(x)PS(3) (x = 0.3). X-ray diffuse scattering from NiPS(3) shows pronounced streaking along c, indicative of stacking faulting in these layered compounds. Electron diffraction from Ni(1 - x)Mg(x)PS(3) (x = 0.3) shows substantial diffuse scattering due to short-range order within the ab plane, and this can be modelled by allowing the metal species to cluster. The possibility of clustering has implications for interpretation of the magnetic behaviour of the family, including the glassiness observed in Fe(1 - x)Mn(x)PS(3).
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The structure of stistaite-SbSn, was investigated by single crystal X-ray diffraction and EDX to yield a simple relation between the modulated structure and the composition. Stistaite is found to be incommensurately ordered over the entire stability region.
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The crystal and magnetic structures of LaCa(2)Fe(3)O(8) and NdCa(2)Fe(3)O(8) have been established using a combination of x-ray, neutron and electron diffraction. It was already considered likely that LaCa(2)Fe(3)O(8) and NdCa(2)Fe(3)O(8) were made up of stacked perovskite-like layers of FeO(6) octahedra, with every third layer being replaced by a layer of tetrahedrally coordinated Fe, rather like a variation on the Brownmillerite (Ca(2)Fe(2)O(5)) structure type. We have gone further and determined a likely space group for this Grenier phase and determined the magnetic structure of the compounds at room temperature. The space group is found to be P 2(1)ma (b axis as the long axis), and the crystal structure has been refined, subject to the stacking faulting along the long axis that is apparent in electron diffraction patterns. The magnetic structure of LaCa(2)Fe(3)O(8) is shown to consist of antiferromagnetically ordered Fe(3+) ions on a collinear G-type antiferromagnetic structure, with the magnetic moments most likely (anti)parallel with the c axis, and of magnitude 3.4 ± 0.2µ(B) (3.6 ± 0.2µ(B) for NdCa(2)Fe(3)O(8)). The result is reasonable given the magnetic structures of the end members of the La(1-x)Ca(x)FeO(3) series, LaFeO(3) (x = 0) and Ca(2)Fe(2)O(5) (x = 1).
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Urine samples from 467 men living in the Stockholm area were tested with the polymerase chain reaction (PCR), Roche Amplicor, and with an enzyme-linked immunosorbent assay, Syva MicroTrak EIA, for detection of Chlamydia trachomatis. The predictive value of urine versus urethral samples was subsequently compared on a second urethral sample from 25 C. trachomatis-positive cases. The urethral samples were in addition cultured for C. trachomatis. C. trachomatis was found more often in urine by Roche Amplicor than by Syva MicroTrak, 9.9% and 7.9%, respectively. Nine urine samples, positive only by Amplicor, could be confirmed as true positives by complementary testing. C. trachomatis was detected with the same frequency in urine and urethral samples. The sensitivity was highest for PCR, 88% and 92%, and lowest for EIA, 76% and 80%, on urethral and urine samples, respectively. Urine sampling, offering a non-invasive procedure, was found suitable for the diagnosis of C. trachomatis in men, with the use of Roche Amplicor.
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Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/urina , Chlamydia trachomatis , Prática de Saúde Pública/normas , Medição de Risco , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Uretra/microbiologiaRESUMO
STUDY DESIGN: In this prospective, consecutive, controlled cohort study, the authors analyzed the impact of a differentiated, individual-based treatment program on sick leave during pregnancy for women experiencing lumbar back or posterior pelvic pain during pregnancy. OBJECTIVE: To identify patients with pain early in pregnancy and, by means of individual information and differentiated physiotherapy, reduce sick leave during pregnancy. SUMMARY OF BACKGROUND DATA: Sick leave for back pain during pregnancy is common, and treatment programs have been aimed at reducing pain, for that reason. In Sweden, the average sick leave due to back pain during pregnancy is 7 weeks. METHODS: All pregnant women who attended a specific antenatal clinic and experienced lumbar back or posterior pelvic pain were included in an intervention group, and results were compared with women in a control group from another antenatal clinic. RESULTS: The intervention group comprised 54 women, compared with 81 women in the control group. Thirty-three women were on sick leave for an average of 30 days in the intervention group versus 45 women for an average of 54 days in the control group (P < 0.001). The reduction in sick leave reduced insurance costs by approximately $53,000 U.S. CONCLUSIONS: Sick leave for lumbar back and posterior pelvic pain in the intervention group was significantly reduced with the program, and the program was cost effective.
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Dor Lombar/reabilitação , Dor Pélvica/reabilitação , Modalidades de Fisioterapia , Complicações na Gravidez , Licença Médica/economia , Estudos de Coortes , Feminino , Humanos , Dor Lombar/economia , Medição da Dor , Dor Pélvica/economia , GravidezRESUMO
We compared the angle of trunk rotation (ATR) from scoliometer readings with Cobb angle measurements of the lateral deviation of the spine in 150 children referred to hospital for evaluation of scoliosis. The mean Cobb angle in thoracic curves was 16 degrees. In thoracolumbar curves 17 degrees and in lumbar curves 20 degrees. In thoracic curves and in right convex curves no patient with a Cobb angle of 25 degrees or more had an ATR below 9 degrees. In thoracolumbar and lumbar and in left convex curves, 7 degrees ATR was occasionally associated with scoliosis of 25 degrees or more. The correlation coefficient between the ATR and Cobb angle in right convex curves was 0.65 compared to 0.57 in left convex curves. We conclude that a criterion of > 7 degrees ATR for thoracic or right convex curves and one of > 6 degrees ATR for thoracolumbar and lumbar or left convex curves seem adequate for identification of patients with Cobb angles of 25 degrees or more, which reduces the need for spinal radiography and follow-up outside the school screening programs.
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Vértebras Lombares/fisiopatologia , Escoliose/fisiopatologia , Vértebras Torácicas/fisiopatologia , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Vértebras Lombares/anatomia & histologia , Vértebras Lombares/diagnóstico por imagem , Masculino , Programas de Rastreamento/métodos , Ortopedia/métodos , Postura/fisiologia , Radiografia , Estudos Retrospectivos , Rotação , Escoliose/diagnóstico , Vértebras Torácicas/anatomia & histologia , Vértebras Torácicas/diagnóstico por imagemRESUMO
The incidence of scoliosis and trunk asymmetry were studied in 60 patients with upper limb dysmelia of the transverse type. The evaluations were based on radiographic measurements of the spine and scoliometer readings of the angle of trunk rotation (ATR), which were correlated with the side and level of the limb deficiency and also with leg length-inequality (LLI). Nineteen patients (31%) had a scoliosis between 10 and 19 degrees, whereas the curves were between 5 and 10 degrees in another 30 patients and the remainder had no measurable curve. The scoliosis seemed at least partly to be of postural origin as LLI significantly correlated with the direction of the curves, but there was no correlation between the Cobb angles and the magnitude of LLI. The scoliometer readings did not correlate with the scoliosis or LLI. Our findings indicate that most patients with upper limb transverse amputations do not develop a significant scoliosis. A scoliometer screen has a low positive predictive rate for scoliosis and the diagnosis of scoliosis requires a radiograph of the spine.
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Braço/anormalidades , Ectromelia/complicações , Escoliose/etiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Desigualdade de Membros Inferiores/complicações , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Escoliose/diagnósticoRESUMO
PURPOSE: The main purpose of this prospective study was to analyze whether 1 year of treatment was as effective as 3 years with respect to remission rate in children with idiopathic epilepsy. METHODS: Treatment for epileptic seizures was started in 207 children aged 2-16 years. They were randomized to treatment for 1 or 3 years. At the end of the predetermined treatment period, 161 children had been seizure-free for 6 months and the treatment could be gradually withdrawn. RESULTS: The overall remission rate in our group of patients was significantly higher (71%) in the group treated for 3 years than in the group treated for 1 year (53%). However, comparison of remission rates between patients with different seizure types showed statistically significant differences in outcome depending on duration of treatment only in children with complex partial seizures (CPS). CONCLUSIONS: Our results show that 1 year of treatment can be recommended in children with benign partial epilepsy with rolandic spikes (BECT) and in children with simple partial seizures (SPS) but is clearly insufficient in children with CPS. A proper seizure classification is one important tool, although not sufficient, in offering recommendations concerning the duration of treatment in children with idiopathic epilepsy.
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Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Epilepsias Parciais/tratamento farmacológico , Epilepsia Parcial Complexa/tratamento farmacológico , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Estudos Prospectivos , Recidiva , Fatores de Tempo , Resultado do TratamentoRESUMO
The in vitro and in vivo growth of lymphoblastoid cell lines (LCLs), Burkitt lymphomas (BLs) and PBL-derived immunoblastomas in SCID mice was studied in parallel. Most, but not all, of the LCLs tested were tumorigenic in SCID mice. Long-term culturing in vitro was not a necessary prerequisite for tumorigenicity. There was a good correlation between in vivo and in vitro growth. Three major classes of cells could be distinguished on the basis of their growth properties.
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Linfoma de Burkitt/patologia , Herpesvirus Humano 4/isolamento & purificação , Linfoma Imunoblástico de Células Grandes/patologia , Animais , Linfoma de Burkitt/microbiologia , Divisão Celular , Linhagem Celular , Humanos , Linfócitos , Linfoma Imunoblástico de Células Grandes/microbiologia , Camundongos , Camundongos Nus , Camundongos SCID , Transplante de Neoplasias , Transplante HeterólogoRESUMO
In order to overcome the problems of interdosage fluctuations of body fluid concentrations of carbamazepine, a slow-release formulation has been developed. In an open, controlled, within-patient study, the diurnal plasma concentrations of carbamazepine and its 10,11-epoxide were measured in 25 epileptic children first treated with conventional carbamazepine tablets (Tegretol) and then with the Tegretol slow-release preparation. The diurnal plasma concentration curves during treatment with the slow-release formulation showed significantly less variation over 24 hours than during treatment with the ordinary preparation, as measured by the fluctuation index. Mean concentration values also differed significantly, which is explained by a somewhat reduced bioavailability (22% less) of the slow-release formulation. There were no differences in efficacy and tolerability between the two formulations, but there was a clear-cut reduction of reported side effects, especially tiredness, on treatment with the slow-release formulation. For that reason, the slow-release formulation should be a major advantage in treating children with epilepsy, in order to avoid interference with cognitive functions. In 12 children, simultaneous measurements of the concentration of carbamazepine and its epoxide in saliva were made and compared with the plasma values. As expected, the concentration curves corresponded, indicating that saliva sampling is an appropriate alternative for monitoring the concentration of carbamazepine. All children remained on the slow-release preparation after the trial and were followed up for 12 months or more.
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Carbamazepina/análogos & derivados , Carbamazepina/farmacocinética , Ritmo Circadiano/fisiologia , Epilepsias Parciais/sangue , Epilepsia Tônico-Clônica/sangue , Adolescente , Carbamazepina/administração & dosagem , Criança , Pré-Escolar , Preparações de Ação Retardada , Eletroencefalografia/efeitos dos fármacos , Epilepsias Parciais/tratamento farmacológico , Epilepsia Tônico-Clônica/tratamento farmacológico , Feminino , Seguimentos , Humanos , Masculino , Estudos Multicêntricos como AssuntoRESUMO
Recurrences of bacteriuria after treatment occur in 50% to 80% of asymptomatic patients. Previous experience with short-term treatment as well as long-term prophylaxis has been disappointing, with a significant risk of infections, ie, development of symptoms after treatment. Results with nontreatment are described in this report with reference to clinical course, renal growth, and glomerular filtration rate in 26 asymptomatic girls with established renal scarring and bacteriuria. Acute pyelonephritis was not seen in those with continuing bacteriuria or spontaneous clearance. Neither in scarred nor in unscarred kidneys did the duration of bacteriuria influence renal growth or glomerular filtration rate. Asymptomatic patients with bacteriuria may gain from nontreatment and may have a reduced risk of pyelonephritic attacks.
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Bacteriúria/terapia , Cicatriz , Nefropatias , Adolescente , Bacteriúria/complicações , Bacteriúria/diagnóstico , Bacteriúria/fisiopatologia , Criança , Pré-Escolar , Feminino , Taxa de Filtração Glomerular , Humanos , Recidiva , Estudos Retrospectivos , Refluxo Vesicoureteral/diagnóstico , Refluxo Vesicoureteral/epidemiologiaRESUMO
Lipid composition was studied on cerebral tissue from nine children who had died of a progressive encephalopathy called the infantile form of neuronal ceroid lipofuscinosis (INCL) or polyunsaturated fatty acid lipidosis (PFAL). In the terminal stage of the disease, the concentrations of all lipid classes were found to be significantly reduced in the cerebral and cerebellar cortex and white matter. The concentration of gangliosides of the cerebral cortex was 15% and that of cerebrosides (galactosylceramide) in white matter 0.2-5% of the normal values for the children's ages. The reduction of gangliosides mainly affected those of the gangliotetraose series, particularly GD1a. The fatty acids of the linolenic acid series were strongly reduced in ethanolamine and serine phosphoglycerides. A very large increase up to 100-fold of oligoglycosphingolipids of the globo series and two fucose-containing lipids of the neolacto series was found in the forebrain of the three advanced cases examined. The brain tissue also contained very high concentrations of mono-, di-, and trisialogangliosides of the lacto and neolacto series, gangliosides with type 1 chain dominating. The structures of the gangliosides were tentatively identified by gas chromatography-mass spectrometry and monoclonal antibodies with carefully determined epitope specificity. The gangliosides and neutral glycosphingolipids had very similar fatty acid composition, consisting of about 40% stearic acid and 40% C24-acids.
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Encéfalo/metabolismo , Ácidos Graxos Insaturados/metabolismo , Gangliosídeos/metabolismo , Glicoesfingolipídeos/metabolismo , Lipidoses/metabolismo , Lipofuscinoses Ceroides Neuronais/metabolismo , Triexosilceramidas , Córtex Cerebelar/metabolismo , Córtex Cerebral/metabolismo , Criança , Ácidos Graxos/metabolismo , Galactosilceramidas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Globosídeos/metabolismo , Glicolipídeos/metabolismo , Humanos , Cinética , Lipídeos de Membrana/metabolismoRESUMO
Twenty-five healthy infants were followed from the newborn period to the age of eighteen months, by evaluation of their neuromotor performance. Evaluation of the specific postural reaction patterns (as described by Vojta) did not seem to be any use as a "short-cut" for the early diagnosis of neuromotor abnormalities, a considerable number of deviations from the normal/optimal pattern being noted even in completely normal infants.
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Deficiências do Desenvolvimento/diagnóstico , Recém-Nascido , Destreza Motora/fisiologia , Humanos , Lactente , PosturaRESUMO
Thirty children with early signs of cerebral neuromotor disturbances according to "Vojta criteria" were followed until the age of thirty-three months to six years. Twelve children were treated with early physiotherapy according to Bobath, ten children were treated according to Vojta and eight constituted a control group. The infants tended for early physical therapy were divided by random into two different groups. The neonatal risk factors, however, proved to be unevenly distributed among the infants in the Vojta- and the Bobath-treated groups - the latter being more heavily burdened in this respect. Vojta has claimed that his method of early physiotherapy is able to prevent the development of cerebral palsy (cp) of "uncomplicated" (but not of "complicated") type. At follow-up we found one child out of nine with "uncomplicated" cp in the Vojta group against three out of six in the Bobath- and two out of six in the control group. These differences, however, are not statistically significant. Further detailed studies with greater groups of children seem necessary to help us to clarify these problems. The psychological aspects of early physiotherapy should be thoroughly considered and this is particularly important in connection with the Vojta method.
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Paralisia Cerebral/terapia , Modalidades de Fisioterapia , Paralisia Cerebral/prevenção & controle , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Terapia por Exercício , Feminino , Seguimentos , Humanos , Lactente , Masculino , Distribuição AleatóriaRESUMO
The proposal by V. Vojta in 1974 to prevent development of cerebral palsy in "motor risk" infants by special treatment has been investigated in 11 Danish and 10 Swedish babies and compared with 30 control infants with similar risk, who were not given Vojta treatment. We found a tendency for "uncomplicated" cerebral palsy cases to accumulate in the control group, although the difference was non-significant on 1 5% level. Further controlled studies must be completed before it is possible to accept the prophylactive treatment of cerebral palsy recommended by Vojta.