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We studied the magnetic ordering of thin films and bulk crystals of rutile RuO_{2} using resonant x-ray scattering across the Ru L_{2} absorption edge. Combining polarization analysis and azimuthal angle dependence of the magnetic Bragg signal, we have established the presence and characteristic of collinear antiferromagnetism in RuO_{2} with T_{N}>300 K. In addition to revealing a spin-ordered ground state in the simplest ruthenium oxide compound, the persistence of magnetic order even in nanometer-thick films lays the ground for potential applications of RuO_{2} in antiferromagnetic spintronics.
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INTRODUCTION: The standard aftercare treatment (according to the AO guideline) for surgically treated trauma patients with fractures of the tibial plateau is non-weight bearing or partial weight bearing for 10-12 weeks. The purpose of this study was to investigate the current state of practice among orthopaedic surgeons and trauma surgeons in choosing the criteria and the time period of restricted weight bearing after surgically treated tibial plateau fractures. MATERIALS AND METHODS: A web-based survey was distributed among members of the Dutch Trauma Society and Dutch Orthopaedic Society to identify the most commonly applied protocols in terms of the post-operative initiation and level of weight bearing in patients with tibial plateau fractures. RESULTS: One hundred and eleven surgeons responded to the survey. 72.1% of the respondents recommended starting weight bearing earlier than the 12 weeks recommended by the AO guideline; 11.7% recommended starting weight bearing immediately, 4.5% after 2 weeks and 55.9% after 6 weeks. Moreover, 88.7% of the respondents reported deviating from their own local protocol. There is little consensus about the definition of 100% weight bearing and how to build up weight bearing over time. CONCLUSION: This study demonstrates that consensus about the weight bearing aftercare for tibial plateau fractures are limited. A large majority of surgeons do not follow the AO guideline or their own local protocol. More transparent criteria and predictors are needed to design optimal weight-bearing regimes for the aftercare of tibial plateau fractures.
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Cirurgiões Ortopédicos/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Fraturas da Tíbia , Humanos , Países Baixos , Guias de Prática Clínica como Assunto , Inquéritos e Questionários , Fraturas da Tíbia/reabilitação , Fraturas da Tíbia/cirurgia , Suporte de CargaRESUMO
An aberration-corrected JEOL 2200FS scanning-transmission electron microscope (STEM), equipped with a high-angle annular dark-field detector (HAADF), is used to monitor the coalescence and sintering of Pt nanoparticles with an average diameter of 2.8 nm. This in situ STEM capability is combined with an analysis methodology that together allows direct measurements of mass transport phenomena that are important in understanding how particle size influences coalescence and sintering at the nanoscale. To demonstrate the feasibility of this methodology, the surface diffusivity is determined from measurements obtained from STEM images acquired during the initial stages of sintering. The measured surface diffusivities are in reasonable agreement with measurements made on the surface of nanoparticles, using other techniques. In addition, the grain boundary mobility is determined from measurements made during the latter stages of sintering.
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Cristalização/métodos , Aumento da Imagem/métodos , Microscopia Eletrônica de Transmissão e Varredura/métodos , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanotecnologia/métodos , Platina/química , Temperatura Alta , Substâncias Macromoleculares/química , Teste de Materiais/métodos , Conformação Molecular , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
Serially obtained urinary polyamine levels were determined for 192 patients during a specified time period. The number of patient urine samples totaled 938. The patients had tumors of either the breast, stomach, prostate, or female genital tract, or metastatic carcinomas of unknown origin. Tumor activity and tumor volume, along with other clinical information, were also recorded during the time period. Possible associations between tumor activity and tumor volume on one hand, and polyamine levels on the other hand, were explored via different statistical analyses. For each tumor type, statistically significant group differences were found in polyamine levels between patients with nonactive tumors and patients with active large tumors. Predictive values of polyamine assays for change in disease activity and stability in disease nonactivity for tumors of the breast, female genital tract, and prostate were also computed. For breast tumors, these predictive values do not support the clinical utility of the use of polyamine levels to monitor disease states. For tumors of the female genital tract and prostate, these predictive values yield an indeterminant conclusion.
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Neoplasias/patologia , Poliaminas/urina , Adulto , Idoso , Neoplasias da Mama/patologia , Feminino , Neoplasias dos Genitais Femininos/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias/urina , Neoplasias da Próstata/patologia , Neoplasias Gástricas/patologiaRESUMO
One hundred ninety patients with a variety of tumor presented within a specified time period and fit a specified protocol. Multiple serial urinary putrescine, spermidine, and spermine levels were obtained in these patients, and their disease activity over time, defined as either active or nonactive, was determined by clinical examination, the results of laboratory tests, and radiological criteria. Twenty-four-hr urine collections were used for analysis of polyamine levels. A linear mixed-effects model and the method of maximum likelihood estimation were used for statistical analysis. Statistically significant differences were found in polyamine levels between patients with active or nonactive disease for tumors of the breast, stomach, prostate, female genital tract, and a variety of metastatic carcinomas of unknown origin. There were 105 patients with these tumors; 319 polyamine determinations were obtained from this subset of patients. Our results suggest that serial determination of polyamine levels in urine may have clinical utility for monitoring the disease states for these tumors.
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Neoplasias/diagnóstico , Putrescina/urina , Espermidina/urina , Espermina/urina , Neoplasias da Mama/diagnóstico , Técnicas de Laboratório Clínico , Feminino , Neoplasias dos Genitais Femininos/diagnóstico , Humanos , Masculino , Metástase Neoplásica , Neoplasias/urina , Neoplasias da Próstata/diagnóstico , Neoplasias Gástricas/diagnósticoRESUMO
INTRODUCTION: Non-or partial weight bearing is frequently the standard treatment after peri-articular lower extremity fractures. Displaced talar neck fractures are severe injuries compromising vascularity of the corpus and consequently are at risk for non-union and avascular necrosis, the main reason to restrict weight bearing for up to three months according to most literature. CASE PRESENTATION: We report a case of a 31-year old male with a high impact car accident. His pelvic ring and Hawkins II talar fracture were treated by open reduction and internal fixation. Rehabilitation was based on permissive weight bearing following wound healing. His fractures healed uneventfully and he was able to run freely, without any discomfort within 8 weeks. Radiological evaluation of the talus showed complete bone healing without signs of avascular necrosis. At one year follow-up, the patient is free of the symptoms. CONCLUSION: We might consider changing the restricted or non-weight bearing protocol in surgically treated talar neck fractures at our centre and allow early weight bearing, based on body awareness and the creation of a safe environment during the rehabilitation phase.
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Rechargeable batteries such as Li ion/Li metal batteries are widely used in the electronics market but the chemical instability of the electrolyte limits their use in more demanding environmental conditions such as in automotive, oil exploration, or mining applications. In this study, a series of alkyl phosphonium ionic liquid electrolyte are described with high thermal stability and solubility for LiTFSI. A lithium metal battery (LMB) containing a tailored phosphonium ionic liquid/LiTFSI electrolyte operates at 100 °C with good specific capacities and cycling stability. Substantial capacity is maintained during 70 cycles or 30 days. Instant on-off battery operation is realized via the significant temperature dependence of the electrolyte material, demonstrating the robustness and potential for use at high temperature.
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Radiation therapy is effective for palliation of painful metastatic osseous lesions. Various fractionation doses have been previously described. The present study was initiated to evaluate the efficacy of a high single dose of radiation on pain relief, with the goal of reducing the number of radiation sessions to a minimum. Treatment consisted of a high single dose of radiation ranging between 6 to 10 Gy administered to painful osseous metastases. Prior to radiation therapy response to conservative analgesic therapy was minimal in most cases. Response to radiation therapy thereafter was 71.3% lasting up to 6 and 12 months in 37.3% and 20.9% of cases respectively.
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Neoplasias Ósseas/radioterapia , Cuidados Paliativos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/secundário , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem RadioterapêuticaRESUMO
A randomized trial was performed to determine if combination chemotherapy (CT) with estrogen (E) priming (E+ study arm) was superior to CT alone (E- study arm) in patients with advanced breast cancer. CT for both arms included adriamycin + vincristine (AV) starting on day 7 alternating with cytoxan + methotrexate + fluorouracil (CMF) starting on day 28, the entire cycle repeated every 6 weeks. Estrogen priming consisting of 2 mg estradiol + 1 mg estriol (E+ arm) was given orally twice daily beginning on day 1 and continuously through CT until disease progression or unacceptable toxicity. Performance status (KPS) for all patients (n=19, E+ arm; n=22, E- arm) ranged between 70-100%. Mean age (53 y, E+ arm; 56 y, E- arm), menopausal and estrogen receptor status and treatment duration (approximately 38 weeks) were similar for both groups. Estrogen priming did not alter or enhance CT toxicity. Objective responses (CR,PR) were noted in 79% on the E+ arm (CR=11%, PR=68%) and in 73% on the E- arm (CR=9%, PR=64%). Thus, estrogen priming in this cohort of patients with advanced breast cancer did not appear to add to the toxicity or palliative benefit of CT.
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Leukocyte alkaline phosphatase (LAP) activity in peripheral blood was determined in 113 patients with non-metastatic malignancies, 36 patients with metastatic spread, and 22 individuals who served as controls. The LAP score of the non-metastatic cancer patients was significantly higher (p less than 0.001) than the controls, and the score of the metastatic group was further increased significantly as compared to both control (p less than 0.001) and non-metastatic groups (p less than 0.001). The results of this survey suggest that the level of LAP score in peripheral blood might be used to differentiate between non-metastatic and metastatic disease and might serve as an aid in prognosis of the patients.
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Fosfatase Alcalina/sangue , Leucócitos/enzimologia , Neoplasias/enzimologia , Feminino , Humanos , Masculino , Metástase NeoplásicaRESUMO
A short-term bacterial mutation test, the SOS Chromotest, has been used to detect the excretion in urine of genotoxic metabolites of antineoplastic drugs administered to cancer patients. In this test, the damage to the DNA of the test bacteria is expressed by the production of beta-galactosidase, which can be quantitatively assessed and is proportional to the concentration of the drug. Kinetic curves of excretion for adriamycin, bleomycin, dacarbazine, cis-platinum and vincristine and their mixtures have been constructed from standard curves relating the intensity of the beta-galactosidase response to the concentration of drugs dissolved in normal urine. Comparative data on extraction and concentration of the drugs from urine or serum by means of selective resin or silica columns are presented.
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Protocolos de Quimioterapia Combinada Antineoplásica/urina , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/urina , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Cisplatino/administração & dosagem , Cisplatino/urina , Ciclofosfamida/administração & dosagem , Ciclofosfamida/urina , Doxorrubicina/administração & dosagem , Doxorrubicina/urina , Feminino , Humanos , Testes de Mutagenicidade , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/urina , Vincristina/administração & dosagem , Vincristina/urinaRESUMO
OBJECTIVE: This paper critically reviews research studies examining the long-term effects of cognitive-behavioral therapy interventions for managing pain in rheumatoid arthritis patients. METHODS AND RESULTS: The first section of the paper evaluates long-term results obtained in studies of cognitive-behavioral therapy, arthritis education interventions, and combined cognitive-behavioral therapy-arthritis education interventions. These studies show that although some rheumatoid arthritis patients are able to maintain initial improvements in pain and disability, other rheumatoid arthritis patients do not. In the second section of this review, a cognitive-behavioral model of maintenance of pain coping skills is presented. This model may be useful in increasing our understanding of the relapse process and in planning interventions to enhance and prolong cognitive-behavioral therapy treatment gains. The final section of this paper addresses important future directions for research. The need for empirical studies of relapse and maintenance processes is underscored. CONCLUSIONS: Controlled studies are needed to test the utility of new cognitive-behavioral interventions designed to enhance the long-term maintenance of treatment gains in RA patients. We suggest that a focus on issues of relapse and maintenance may be just as important for medical and surgical interventions for rheumatoid arthritis pain, as it is for cognitive-behavioral therapy interventions.
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Artrite Reumatoide/complicações , Terapia Cognitivo-Comportamental/métodos , Manejo da Dor , Adaptação Psicológica , Adulto , Humanos , Modelos Psicológicos , Dor/etiologia , Dor/psicologia , Educação de Pacientes como Assunto , Recidiva , Fatores de Tempo , Resultado do TratamentoRESUMO
This study compares the effect of single vs fractionated doses of X-radiation on the incisor of the rat. The results showed that fractionated doses are more damaging than a single dose and that three fractionated doses have a stronger effect than five.
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Incisivo/efeitos da radiação , Doses de Radiação , Efeitos da Radiação , Ameloblastos/citologia , Animais , Diferenciação Celular/efeitos da radiação , Polpa Dentária/citologia , Dentina/citologia , Dentina/efeitos da radiação , Incisivo/citologia , Incisivo/diagnóstico por imagem , Odontoblastos/citologia , Odontogênese/efeitos da radiação , Radiografia , Ratos , Erupção DentáriaRESUMO
Pericardial effusion is an unusual complication of meningitis due to Neisseria meningitidis. Primary meningococcal pericarditis without signs of meningitis is rare. Only 18 cases have been described in the literature. The first case was reported in 1939 and the others since 1971. We report a case of primary meningococcal pericarditis in a pregnant woman. Improvement followed prompt antibiotic therapy. Fetal death necessitated abortion by curettage.
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Infecções Meningocócicas/diagnóstico , Pericardite/diagnóstico , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/diagnóstico , Adulto , Ecocardiografia , Eletrocardiografia , Feminino , Morte Fetal , Humanos , Neisseria meningitidis , Derrame Pericárdico/diagnóstico , GravidezRESUMO
Various geometrical data, resulting from anterior scans, of both normal and pathological livers were classified and analyzed statistically from two points of view: Firstly, a static study resulting from observations on pooled scans. This study showed that the frequency distributions of some geometrical parameters in the liver are essentially normal in character. It equally demonstrated that the dimensions of the parameters depend on the degree of the pathology of the liver. Secondly, a study which was carried out on repeated scans recorded on the same patient. It showed that the relative variations of some geometrical parameters of the liver are a function of its degree of pathology, whatever the types of abnormalities considered. The definition of a variable is suggested, the knowledge of which can help to establish the diagnosis.
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Hepatopatias/diagnóstico por imagem , Fígado/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Fatores de TempoRESUMO
A total of 895 CEA estimations were carried out on serum samples from 283 patients with different primary tumor sites. All assays were performed during the period of follow up or treatment of the patients. Concomitantly with CEA estimation, activity of disease was recorded, based on objective laboratory and clinical parameters. The results obtained proved a high accuracy rate for normal CEA values in non-active disease as well as elevated CEA values in active disease. It is concluded that the correlation between CEA level and activity of disease in various neoplasms in an important aid in clinical decision making during the course of disease, provided false positive or negative results are taken into consideration.
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Antígeno Carcinoembrionário/análise , Neoplasias/análise , Humanos , Neoplasias/diagnósticoRESUMO
Based on a lower reported incidence of breast cancer in the Arab population in Israel, nutritional levels were evaluated in a case-control study of 33 Jewish and 10 Arab patients with breast cancer all matched with a first-degree family-related control. Demographic, gynecologic, obstetric, anthropometric, genetically tumor-related, and nutritional data were ascertained through interviews, tests, and questionnaires. Food consumption, calories, protein, fat, and fiber intake, and anthropomorphic measures were calculated. The following results were obtained: 1. Calories of food consumption were significantly higher in Jewish and Arab patients than in their controls. 2. Jewish patients consumed significantly higher levels of monounsaturated fat; Arab patients consumed significantly higher levels of dietary fiber. 3. Animal protein intake was elevated in patients of both ethnic origins as compared with controls. 4. Vegetable fat and monounsaturated fatty acids were elevated in Arab patients as compared with Jewish patients. 5. Body weight of both Arab and Jewish patients was not significantly higher when compared with their controls. 6. Energy consumption and obesity were higher in breast cancer patients than in the controls. This supporting evidence suggests an association between obesity and breast cancer occurrence.
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Mundo Árabe , Neoplasias da Mama/etnologia , Neoplasias da Mama/etiologia , Dieta/efeitos adversos , Etnicidade , Judeus , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Israel/epidemiologia , Jordânia/epidemiologia , Estilo de Vida/etnologia , Análise por Pareamento , Pessoa de Meia-Idade , Avaliação Nutricional , Inquéritos Nutricionais , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/etnologia , Fatores de RiscoRESUMO
The results of thermo-coagulation have been evaluated in a series of 50 patients followed up from two to six years (average three years). Neuralgia disappeared in nearly 80 p. 100 of the cases (however this was obtained with a second operation in nine cases). The frequency of recurrences increase with time: 20 p. 100 during the first two years reaching 40 p. 100 after three years. They were more likely to occur if the post-operative sensory deficit is moderate. Complications directly related to the surgical technique were rare: some faded away relatively quickly (oculo-motor palsies less than 1 p. 100, masseter weakness 20 p. 100 in the first weeks). The only residual problems were related to sensory deficits: in general they were limited to a small cutaneous area and total anesthesia was never been observed. Although paresthesias were noted in 12 p. 100 of the cases, these usually were not really troublesome. Our conclusion, therefore, is that differential thermocoagulation appears to be the best surgical treatment for trigeminal neuralgia.
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Eletrocoagulação , Gânglio Trigeminal/cirurgia , Nervo Trigêmeo/cirurgia , Neuralgia do Trigêmeo/cirurgia , Idoso , Eletrocoagulação/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Parestesia/etiologia , RecidivaRESUMO
A series of 162 arteriovenous malformations (A.V.M.) surgically removed is reported. All patients had a post operative control angiogram showing that the lesion had been totally excised. Supra and infra tentorial A.V.M. are included in the series as well as conscious and comatous patients. The overall mortality has been 11.1% and the mortality in conscious patients has been 6.9%. Mortality is higher when the volume of A.V.M. is over 60 cm3 and when a rupture has occurred. The influence of the operation on epileptic seizures, motor, speech or visual fields deficits has been reviewed in 109 patients who answered to the survey. Morbidity has been higher in patients with a cerebral heamorrhage, therefore the authors advise to operate these patients before the rupture when, for instance, seizures represents the only clinical picture. C.A.T. scan in these epileptic patients is a remarkable investigation to track down A.V.M.