RESUMO
A magnetic helix realizes a one-dimensional magnetic crystal with a period given by the pitch length λh. Its spin-wave excitations-the helimagnons-experience Bragg scattering off this periodicity, leading to gaps in the spectrum that inhibit their propagation along the pitch direction. Using high-resolution inelastic neutron scattering, the resulting band structure of helimagnons was resolved by preparing a single crystal of MnSi in a single magnetic-helix domain. At least five helimagnon bands could be identified that cover the crossover from flat bands at low energies with helimagnons basically localized along the pitch direction to dispersing bands at higher energies. In the low-energy limit, we find the helimagnon spectrum to be determined by a universal, parameter-free theory. Taking into account corrections to this low-energy theory, quantitative agreement is obtained in the entire energy range studied with the help of a single fitting parameter.
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INTRODUCTION: As could be demonstrated for simple and radical nephrectomy, single-incision triangulated umbilical surgery (SITUS) is an interesting alternative to laparoscopic single-site surgery. We present our initial experience with the SITUS technique in radical cystectomy. MATERIALS AND METHODS: Between September 2010 and September 2011, eight patients underwent SITUS radical cystectomy (SITUS Cx), pelvic lymph node dissection and extracorporeal urinary diversion. A cutaneous ureterostomy was performed in three, an ileum conduit in one and an ileal neobladder in four patients. Data were collected prospectively, including patients' characteristics, intraoperative parameters, pathological stage and postoperative outcome. RESULTS: Mean age of the patients was 67 years and the mean body mass index 24 kg/m(2). SITUS Cx was successfully completed in all patients without conversion to conventional laparoscopic or open surgery. Mean surgical time was 434 min and mean estimated blood loss 643 ml. No major intra- or postoperative surgical complications occurred. All patients recovered quickly reporting low postoperative pain levels. Mean hospital stay was 16 (7-24 days). Histopathological evaluation revealed a mean of 16 (6-33) retrieved lymph nodes and no positive margins. CONCLUSION: In the present experience, SITUS Cx proved to be feasible with surgical outcome comparable to conventional techniques. Because SITUS Cx combines the advantages of traditional laparoscopy (straight instruments and triangulation) with those of single-port surgery (superior cosmesis and minimal invasiveness), it presents an attractive alternative to other minimally invasive techniques.
Assuntos
Cistectomia/métodos , Laparoscopia/métodos , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Excisão de Linfonodo/métodos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Prospectivos , Resultado do Tratamento , Umbigo/cirurgia , Ureter/cirurgia , Bexiga Urinária/cirurgiaRESUMO
INTRODUCTION: TURB is the standard approach to bladder tumors but suffers from several disadvantages. Waterjet hydrodissection is a new technology for removing superficial tumors in the GI tract promising to preserve the histological structures of biopsy specimens with favorable long-term results as recent studies have shown. The aim of this study was to show the feasibility and applicability of waterjet hydrodissection for removing papillary superficial bladder tumors. MATERIALS AND METHODS: In five patients diagnosed with superficial papillary bladder tumor, transurethral submucosal dissection was conducted using the T-type I-Jet HybridKnife (Erbe, Tuebingen). The resection edges were labeled by means of electrical coagulation with the HybridKnife. Subsequently, a submucosal fluid cushion specific to the tissue layer was formed by the waterjet implementation function of the HybridKnife, thereby elevating the tumorous tissue. The tumor was endoscopically extracted with a retrieval bag. Biopsy specimens of the tumor edges and base were subsequently collected. RESULTS: All tumors could be resected en bloc, and the lamina propria was intact in all specimens, allowing the pathologist to distinguish between superficial and invasive tumors. Pathological analysis confirmed R0 resection in all samples. CONCLUSION: These initial results prove the feasibility of waterjet hydrodissection for removing bladder tumors. In contrast to conventional TURB, this new technique allows the pathologist to assess the entire lamina propria and the resection edges due to the en-bloc resection and to determine invasiveness as well as R0 versus R1 resection. These first results are promising, long-term oncological follow-up, and prospective randomized surveys investigating the recurrence rate have to be evaluated.
Assuntos
Neoplasias da Bexiga Urinária/cirurgia , Procedimentos Cirúrgicos Urológicos/instrumentação , Procedimentos Cirúrgicos Urológicos/métodos , Água , Idoso , Biópsia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Bexiga Urinária/patologiaRESUMO
Dichlofluanid (N-dichlorofluoromethylthio-N'-dimethyl-N-phenylsulphamide) is used as booster biocide in antifouling paints. The occurrence of dichlofluanid and its metabolite DMSA (N'-dimethyl-N-phenyl-sulphamide) was monitored in seawater and marine sediment from three Greek marinas. Seawater and sediment samples were collected at three representative positions and one suspected hotspot in each marina and shipped to the laboratory for chemical analysis. As part of the project, an analytical method had been developed and validated. Furthermore, some additional experiments were carried out to investigate the potential contribution of paint particle bound dichlofluanid on the total concentration in the sediment. As expected, given its known high hydrolytic degradation rate, no detectable concentrations of dichlofluanid were measured in any of the seawater samples. DMSA was detected in seawater samples at very low concentrations varying from <3 ng l(-1) (LOD) to 36 ng l(-1). During method validation, it had already been demonstrated that dichlofluanid is unstable in sediment and can therefore only be determined as its metabolite DMSA. In a separate experiment, in which marine sediment was spiked with artificial paint particles containing dichlofluanid and then analysed according to the validated method, it was demonstrated that if there is any dichlofluanid originating from paint particles, this would be determined as DMSA. No DMSA was detected in any of the sediment samples. It could therefore be concluded that there were no significant concentrations of dichlofluanid in the sediment samples.
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Compostos de Anilina/análise , Antibacterianos/análise , Sedimentos Geológicos/química , Pintura , Água do Mar/química , Compostos de Anilina/metabolismo , Antibacterianos/metabolismo , Biodegradação Ambiental , Monitoramento Ambiental , Grécia , Hidrólise , Sulfonamidas/análise , Sulfonamidas/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismoRESUMO
We report on our early experience with the use of the Partridge nylon cerclage. This system was employed as a supplementary fixation in 18 femoral fractures in elderly patients (average age, 78 years). Indications of its use were reduction of comminuted fragments and enhancement of the grip of the main fixation device on osteoporotic femora or in femora with a prosthesis in situ. All fractures but one healed primarily. At an average follow-up time of 25 months, 15 of the 18 patients were ambulatory. Radiographic review showed that the cerclage did not cause cortical avascularity and that none of the straps used failed. We concluded that the internal fixation of difficult femoral fractures in the elderly can be easily and effectively strengthened by the use of this cerclage system.
Assuntos
Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas/instrumentação , Dispositivos de Fixação Ortopédica , Idoso , Idoso de 80 Anos ou mais , Placas Ósseas , Feminino , Prótese de Quadril , Humanos , Masculino , Pessoa de Meia-Idade , Nylons , Osteoporose/complicações , Falha de Prótese , ReoperaçãoRESUMO
PURPOSE: Diurnal intraocular pressure (IOP) measurements are recommended in cases of visual field deterioration in glaucoma patients. In this study the rationale of 24 h versus 48 h IOP measurements was investigated. PATIENTS AND METHODS: Mean IOP and maximum IOP values were obtained in 80 patients over a period of 48 h. The IOP measurements (Goldmann tonometry) of day 1 and 2 (taken every 4 h) were compared. To reduce interindividual and intraindividual differences of measurements the statistical calculation took a tolerance level of ± 2 mmHg and ± 1 mmHg into account. RESULTS: Maximum IOP measurements were found to differ between 37.5 % and 65.0% respectively for right eyes and 28.8 % and 47.5% respectively for left eyes depending on the measurement tolerance (±2 mmHg or ±1 mmHg) between day 1 and day 2. Mean IOP values were found to differ by 25 % and 51.3 % respectively for right eyes and 26.3 % and 46.3% respectively for left eyes (± 2 or ± 1 mmHg in) between day 1 and day 2. A time-related clustering of extreme deviations could not be found but the maximum values from all patients were found to be roughly equally distributed over daytime and nighttime hours. CONCLUSIONS: Both maximum IOP and mean IOP measurements were found to differ by at least ± 2 or ± 1 mmHg between day 1 and 2 at a significant percentage and the maximum values did not peak at a predictable time point during the 48 h. Therefore, 48 h IOP measurements appear to be more reliable than 24 h measurements.
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Ritmo Circadiano , Glaucoma/diagnóstico , Glaucoma/fisiopatologia , Pressão Intraocular , Hipertensão Ocular/diagnóstico , Hipertensão Ocular/fisiopatologia , Tonometria Ocular/métodos , Idoso , Diagnóstico por Computador/métodos , Feminino , Glaucoma/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/complicações , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
A case report is presented in which post-operatively a distinct macroglossia including an additional swelling running up to the trachea developed within the framework of a neurosurgical intervention in a seated position. Pathomechanisms and possible therapeutic methods are described and discussed with the help of a review of the literature.
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Complicações Intraoperatórias/etiologia , Macroglossia/etiologia , Procedimentos Neurocirúrgicos/efeitos adversos , Postura/fisiologia , Idoso , Feminino , Humanos , Complicações Intraoperatórias/fisiopatologia , Macroglossia/fisiopatologia , Tomografia Computadorizada por Raios X , TraqueostomiaRESUMO
Using scanning tunneling spectroscopy, we investigated the temperature dependence of the quasiparticle density of states of overdoped Bi(2)Sr(2)CuO(6+delta) between 275 mK and 82 K. Below T(c) = 10 K, the spectra show a gap with well-defined coherence peaks at +/-Delta(p) approximately 12 meV, which disappear at T(c). Above T(c), the spectra display a clear pseudogap of the same magnitude, gradually filling up and vanishing at T(*) approximately 68 K. The comparison with Bi(2)Sr(2)CaCu(2)O(8+delta) demonstrates that the pseudogap and the superconducting gap scale with each other, providing strong evidence that they have a common origin.
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Rhizocticin A, the main component of the antifungal, hydrophilic phosphono-oligopeptides of Bacillus subtilis ATCC 6633, was used for sensitivity testing and experiments into the molecular mechanism of the antibiotic action. Budding and filamentous fungi as well as the cultivated nematode Caenorhabditis elegans were found to be sensitive, whereas bacteria and the protozoon Paramecium caudatum were insensitive. Rhizoctonia solani was inhibited in agar dilution tests but not in diffusion tests. The antifungal effect of rhizocticin A was neutralized by a variety of amino acids and oligopeptides. Oligopeptide influence was mainly understood as transport antagonism, and it was concluded that the antibiotic enters the recipient cell via the peptide transport system. L- and D-cystine were also identified as potent, general antagonists of the oligopeptide transport. The rhizocticin-antagonism of four other amino acids was taken as a clue to the site of action. Provided that rhizocticin A is split by peptidases of the target cell into inactive L-arginine and toxic L-2-amino-5-phosphono-3-cis-pentenoic acid (L-APPA), the latter may interfere with the threonine or threonine-related metabolism.
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Antifúngicos/farmacologia , Bacillus subtilis/metabolismo , Fungos/efeitos dos fármacos , Aminoácidos/antagonistas & inibidores , Aminoácidos/farmacologia , Animais , Antifúngicos/antagonistas & inibidores , Bactérias/efeitos dos fármacos , Eucariotos/efeitos dos fármacos , Fermentação , Estrutura Molecular , Nematoides/efeitos dos fármacos , Oligopeptídeos/farmacologia , Compostos Organofosforados/antagonistas & inibidores , Compostos Organofosforados/farmacologiaRESUMO
The use of opioids in the treatment of chronic pain is sometimes accompanied by inadequate pain relief and opioid-specific side-effects. Opioid rotation is a therapeutic approach, that can improve analgesia and provide a more advantageous analgesia and toxicity relationship. This article presents a case report and discusses the mechanisms, indications and possibilities of opioid rotation.
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Dor/tratamento farmacológico , Administração Cutânea , Doença Crônica , Fentanila/administração & dosagem , Fentanila/uso terapêutico , Humanos , Hidromorfona/administração & dosagem , Hidromorfona/uso terapêutico , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Morfina/administração & dosagem , Morfina/uso terapêutico , Neoplasias/complicações , Dor/etiologiaRESUMO
The case of a 55-year-old woman is described where shoulder pain was successfully treated with a suprascapular catheter. During arthroscopy of the shoulder the catheter was detected in the subacromial space. The reasons and consequences of an abnormal position of the suprascapular catheter are discussed.
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Artroscopia , Cateterismo Periférico/efeitos adversos , Erros Médicos , Bloqueio Nervoso/efeitos adversos , Ombro/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Ombro/anatomia & histologia , Dor de Ombro/patologia , Dor de Ombro/terapiaRESUMO
1. Reductive metabolism of p-nitrobenzoic acid and neoprontosil in rat liver microsomes was studied in the presence of haemin, haemoglobin and myoglobin. 2. Microsomal nitro reduction is enhanced 4-fold in the presence of haemoglobin, whereas azo reduction is not affected. 3. Microsomal nitro reduction is enhanced to a similar extent by haemoglobin, haemin and boiled haemoglobin, whereas myoglobin is about half as active. 4. Maximal enhancement of microsomal nitro reductase activity by haemoglobin is achieved at high substrate concentration (6 mM) and low microsomal protein concentration (0.5--1.0 mg/ml). 5. Control microsomal nitro reduction as well as the haemoglobin-enhanced microsomal nitro reduction are inhibited completely by O2 and CO whereas potassium azide as a ligand of ferric haem iron is a less potent inhibitor.
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Heme/análogos & derivados , Hemeproteínas/farmacologia , Hemina/farmacologia , Microssomos Hepáticos/metabolismo , Nitrocompostos/metabolismo , Animais , Hemoglobinas/farmacologia , Temperatura Alta , Técnicas In Vitro , Mioglobina/farmacologia , Nitrobenzoatos/metabolismo , Oxirredução/efeitos dos fármacos , Oxigênio/farmacologia , Ratos , Estimulação QuímicaRESUMO
Population studies were carried out on German and Turkish individuals from South-West Germany using the short tandem repeat (STR) systems HumFibra (n = 138 Turkish and 1161 German individuals) and HumACTBP2 (n = 202 Turkish and 1338 German individuals). After electrophoresis 19 alleles could be identified for HumFibra and 55 for HumACTBP2. No significant deviations from Hardy-Weinberg equilibrium were observed.
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Frequência do Gene , Sequências de Repetição em Tandem , População Branca/genética , Alelos , Análise por Conglomerados , DNA/análise , Medicina Legal , Genótipo , Alemanha , Humanos , Polimorfismo de Fragmento de Restrição , Turquia/etnologiaRESUMO
We report scanning tunneling spectroscopy imaging of the vortex lattice in single crystalline MgB2. By tunneling parallel to the c axis, a single superconducting gap (Delta=2.2 meV) associated with the pi band is observed. The vortices in the pi band have a large core size compared to estimates based on H(c2) and show an absence of localized states in the core. Furthermore, superconductivity between the vortices is rapidly suppressed by an applied field. These results suggest that superconductivity in the pi band is, at least partially, induced by the intrinsically superconducting sigma band.