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Empirical evaluations of fundamental characteristics of the physical and chemical interaction of hydrogen with graphene layers in different kinds of graphite and novel carbonaceous nanomaterials of graphene layer structure have been carried out. This was done by using the approaches of the thermodynamics of reversible and irreversible processes for analysis of the adsorption, absorption, diffusion, the temperature-programmed desorption (TPD) and other experimental data and comparing such analytical results with first-principles calculations. Such an analysis of a number of the known experimental and theoretical data has shown a real possibility of the multilayer specific adsorption (intercalation) of hydrogen between graphene layers in novel carbonaceous nanomaterials. This is of relevance for solving the bottle-neck problem of the hydrogen on-board storage in fuel-cell-powered vehicles, and other technical applications.
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OBJECTIVE: Functional androgenization (FA) can be divided into five groups corresponding to the predominant organ pathology as recently shown by our group: functional cutaneous androgenization (FCA, skin) and FA syndrome (FAS) I (ovary, lean individual), II (adrenal gland), III (ovary, fat tissue, pancreas, and hyperinsulinemia), and IV (residual FA dysfunctions). Group-specific clusters are based on primary variables such as LH, testosterone, DHEAS, sex hormone-binding globulin (SHBG), body mass index (BMI), glucose, insulin, and enlarged polyfollicular ovaries. Because anti-Müllerian hormone (AMH) positively correlates with the antral follicle count, its relevance as an additional primary variable for classifying FA was investigated. DESIGN: In this study, 178 patients with FA were consecutively enrolled and classified into the five FA groups as described earlier and 30 women with regular menstrual cycles served as control. METHODS: Primary variables and serum AMH were analyzed in the early follicular phase. RESULTS: FA patients showed significantly elevated AMH levels (11.1±6.7âng/ml) versus control (3.0±2.0âng/ml; P<.0001). AMH was significantly increased in groups FAS I (15.6±5.8âng/ml) and FAS III (11.6±6.6âng/ml) compared with groups FCA (7.0±3.8âng/ml), FAS II (5.05±3.0âng/ml), and FAS IV (6.9±4.6âng/ml) and correlated positively (P<.0001) with LH (r=0.538) and testosterone (r=0.368). In regression and multivariate analyses, AMH was not dependent on SHBG, DHEAS, BMI, glucose, or insulin. In receiver operating characteristic analysis, 9.21âng/ml AMH showed 90% specificity with 71.2% sensitivity for the diagnosis of the two ovarian FA groups, FAS I and III. CONCLUSION: AMH confirms the novel stratification system and constitutes a useful primary variable in the algorithm of FA classification.
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Hormônio Antimülleriano/sangue , Técnicas de Diagnóstico Endócrino , Síndrome do Ovário Policístico/classificação , Síndrome do Ovário Policístico/diagnóstico , Virilismo/classificação , Virilismo/diagnóstico , Adolescente , Adulto , Hormônio Antimülleriano/análise , Hormônio Antimülleriano/fisiologia , Biomarcadores/análise , Biomarcadores/sangue , Estudos de Casos e Controles , Diagnóstico Diferencial , Técnicas de Diagnóstico Endócrino/tendências , Feminino , Humanos , Hormônio Luteinizante/sangue , Concentração Osmolar , Síndrome do Ovário Policístico/sangue , Curva ROC , Testosterona/sangue , Virilismo/sangue , Adulto JovemRESUMO
The possibilities of effective solutions of relevant technological problems are considered based on the analysis of fundamental physical aspects, elucidation of the nano-structural mechanisms and interrelations of aging and hydrogen embrittlement of materials (steels) in the hydrogen industry and gas-main industries. The adverse effects which these mechanisms and processes have on the service properties and technological lifetime of materials are analyzed. The concomitant fundamental process of formation of carbohydride-like and other segregation nanostructures at dislocations (with the segregation capacity 1 to 1.5 orders of magnitude greater than in the widely used Cottrell 'atmosphere' model) and grain boundaries is discussed in the context of how these nanostructures affect technological processes (aging, hydrogen embrittlement, stress corrosion damage, and failure) and the physicomechanical properties of the metallic materials (including the technological lifetimes of pipeline steels).
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INTRODUCTION: The acromio-clavicular (AC) joint is very susceptible to degenerative processes that result in pain and functional impairment. One common modality of treatment has been local infiltration of the joint space. Although this procedure has produced notable positive results, needle misplacement occurs frequently. The aim of this investigation is to evaluate the effects of an intra articular infiltration by comparing precise needle placement into the joint space using high-resolution-ultrasound with the conventional palpation technique. METHODS: This prospective and randomized pilot study analysed 20 patients who were assigned either to the "ultrasound" or the "palpation" group. Clinical examinations were performed before treatment and at 1h, 1 week and 3 weeks after a single infiltration of local anaesthetic and corticoid carried out by one specialist. RESULTS: In both groups significant improvement in pain and function was obtained up to one-week post injection. Function remained significantly improved until the last follow-up and did not differ between the two groups. The agent was administered in all patients into the joint space in the ultrasound group. CONCLUSION: Ultrasound guided infiltration of the AC joint is an easily achieved procedure without any complications. However, clinical follow-up did not differ between free-hand and ultrasound-guided AC joint space infiltration.
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Articulação Acromioclavicular/efeitos dos fármacos , Articulação Acromioclavicular/diagnóstico por imagem , Corticosteroides/administração & dosagem , Anestésicos Locais/administração & dosagem , Artralgia/tratamento farmacológico , Palpação/métodos , Ultrassonografia/métodos , Artralgia/diagnóstico por imagem , Feminino , Humanos , Injeções Intra-Articulares/métodos , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos dos fármacos , Estudos Prospectivos , Radiologia/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Ultrassonografia de Intervenção/métodosRESUMO
The analytical consideration of some recent experimental and theoretical data on the hydrogen on-board storage problem shows the necessity and economical expediency of carrying out further basic studies and initiating a constructive discussion on the physical key-note aspects ("open questions") of the hydrogen sorption by carbon-based nanomaterials: Especially, on the hydrogen multilayer intercalation in carbonaceous nanostructures, their relevance for the development of super-adsorbents for fuel-cell-powered vehicles, i.e., storage materials, which satisfy most of the U.S. DOE targets. It is consistent with the U. S. National Academies' recent recommendations and manifestations of the critical situation of the hydrogen storage problem.
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There is a need to identify suitable blends of solvents to dissolve drugs. Empirical approaches, such as trial-and-error and response surface, require several solubility measurements. In this study the UNIFAC method was used to predict solubility in highly nonideal multicomponent systems in which only the solute enthalpy of fusion and melting point must by measured. UNIFAC combines a group contribution approach with the UNIQUAC model for activity coefficients. Parameters characterizing interactions among constituent groups of a molecule have been previously determined from binary vapor pressure data. These tabulated group parameters are used to predict activity coefficients for newly synthesized compounds. These coefficients, together with the ideal solubility, permit a prediction of solubility. The solubility of 4-hexylresorcinol in ethyl acetate, ethyl myristate, and hexane mixtures was both measured and calculated using UNIFAC. The predicted solubilities were within 10% of the experimental solubilities for all but 3 of 21 mixtures. Since the method accounted for positive and negative deviations from ideality in a hydrogen-bonding system of molecules having different sizes, it shows great potential for use in pharmacy.
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Solubilidade , Acetatos , Fenômenos Químicos , Química Farmacêutica , Físico-Química , Hexanos , Hexilresorcinol , Ligação de Hidrogênio , Modelos Biológicos , Miristatos , SolventesRESUMO
Mixture response-surface methodology can be used as a technique to predict solubility in mixed solvent systems. The present report shows that if the intent is to predict solubility in nonideal solutions, mixture response-surface methodology is a better technique than one which assumes a particular mechanism to hold true. This is demonstrated by comparing the predictive ability of the mixture response-surface model with that of an extended Hildebrand approach to nonideal solutions. The nonideal systems are those used by Martin and co-workers involving the solubility of theobromine, caffeine, and theophylline in dioxane-water mixtures.
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Solubilidade , Xantinas/análise , Cafeína/análise , Fenômenos Químicos , Química Farmacêutica , Físico-Química , Solventes , Estatística como Assunto , Teobromina/análise , Teofilina/análiseRESUMO
Review of 298 cases of primary gastric malignancy from 1958 to 1978 revealed 265 cases of adenocarcinoma. Overall 5-year survival rate was a disappointing 5.5%, which was less than the earlier series of Oschner Clinic (7.5%). Curative resections produced a five-year survival rate of 26%. Patients presented with advanced disease; 84% had Stage III or IV disease at time of initial observation. The introduction of fiberoptic endoscopy during this period greatly enhanced the accuracy of preoperative diagnosis of tissue-proven cancer from 6% before fiberoptic to 58% since. Worldwide experience is much better, with overall five-year survival rate of 17.9%. Excellent survival statistics from Japanese studies reflect both the effects of mass surveying and early surgery and the prevalence of superficial spreading type of cancer. Improvement of results in this country will require more aggressive evaluation and earlier surgical intervention.
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Adenocarcinoma/mortalidade , Carcinoma in Situ/mortalidade , Neoplasias Gástricas/mortalidade , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Adulto , Idoso , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/cirurgia , Feminino , Tecnologia de Fibra Óptica , Seguimentos , Gastroscopia , Humanos , Louisiana , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirurgia , Fatores de TempoRESUMO
Carcinoma of the stomach, although its incidence is decreasing in the United States, is still a fatal disease. The results today are actually no better than they were 30 years ago because we are still making late diagnoses. In order to improve our results in the treatment of cancer of the stomach, we must perform fiberoptic gastroscopy in individuals over age 40 who have gastric complaints that do not respond readily to conservative medical therapy. At the time of endoscopy, multiple biopsies of gastric mucosa must be taken. Only in this way can early enough diagnoses be made to increase the survival rate in gastric carcinoma.
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Neoplasias Gástricas/mortalidade , Adulto , Idoso , Europa (Continente) , Feminino , Gastroscopia , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirurgia , Estados UnidosRESUMO
Cardio-respiratory data were obtained on four adult female cynomolgus monkeys, intermittently exposed to CO for eight months and compared with data obtained from the same animals after five weeks of recovery. Due to CO exposure, the arteriovenous oxygen concentration difference and oxygen consumption decreased and blood oxygen affinity increased. However, there was no significant change in cardiac output and mixed venous PO2. The cynomolgus monkeys adapted to chronic CO exposure by reducing their metabolic rate.