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1.
Rozhl Chir ; 101(5): 251-254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35667876

RESUMO

INTRODUCTION: Acute appendicitis is one of the most common acute abdominal conditions. One of its complications is postoperative formation of abscesses in the peritoneal cavity or in the retroperitoneal space. Among other things, appendicoliths left in the peritoneal cavity are responsible for this process. Their release from the lumen occurs preoperatively and during the operation. An appendicolith, with the bacteria present on its surface, provides an environment that supports the onset of an infection. CASE REPORT: The authors present a less common case of a retroperitoneal abscess caused by an incarcerated appendicolith. Unusual is the long period between appendectomy and clinical manifestations of the abscess. The patient underwent surgical treatment with abscess evacuation and extraction of the appendicolith. The postoperative course was adequate; wound healing was supported by negative wound pressure therapy. CONCLUSION: During appendectomy, it is necessary to keep in mind the risk of releasing appendicoliths and their role in infectious complications. A conscientious revision of the peritoneal cavity is required, as well as a good surgical technique. If necessary, imaging methods can help to locate the appendicolith in the postoperative period.


Assuntos
Abscesso Abdominal , Apendicite , Apêndice , Laparoscopia , Abscesso Abdominal/etiologia , Abscesso Abdominal/cirurgia , Abscesso/etiologia , Doença Aguda , Apendicectomia/efeitos adversos , Apendicectomia/métodos , Apendicite/complicações , Apendicite/cirurgia , Humanos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia
2.
Phys Rev Lett ; 115(18): 186102, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26565477

RESUMO

The structural and magnetic properties of ultrathin FeO(111) films on Pt(111) with thicknesses from 1 to 16 monolayers (MLs) were studied using the nuclear inelastic scattering of synchrotron radiation. A distinct evolution of vibrational characteristics with thickness, revealed in the phonon density of states (PDOS), shows a textbook transition from 2D to 3D lattice dynamics. For the thinnest films of 1 and 2 ML, the low-energy part of the PDOS followed a linear ∝E dependence in energy that is characteristic for two-dimensional systems. This dependence gradually transforms with thickness to the bulk ∝E^{2} relationship. Density-functional theory phonon calculations perfectly reproduced the measured 1-ML PDOS within a simple model of a pseudomorphic FeO/Pt(111) interface. The calculations show that the 2D PDOS character is due to a weak coupling of the FeO film to the Pt(111) substrate. The evolution of the vibrational properties with an increasing thickness is closely related to a transient long-range magnetic order and stabilization of an unusual structural phase.

3.
J Microsc ; 259(2): 80-96, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25623622

RESUMO

When electron microscopy (EM) was introduced in the 1930s it gave scientists their first look into the nanoworld of cells. Over the last 80 years EM has vastly increased our understanding of the complex cellular structures that underlie the diverse functions that cells need to maintain life. One drawback that has been difficult to overcome was the inherent lack of volume information, mainly due to the limit on the thickness of sections that could be viewed in a transmission electron microscope (TEM). For many years scientists struggled to achieve three-dimensional (3D) EM using serial section reconstructions, TEM tomography, and scanning EM (SEM) techniques such as freeze-fracture. Although each technique yielded some special information, they required a significant amount of time and specialist expertise to obtain even a very small 3D EM dataset. Almost 20 years ago scientists began to exploit SEMs to image blocks of embedded tissues and perform serial sectioning of these tissues inside the SEM chamber. Using first focused ion beams (FIB) and subsequently robotic ultramicrotomes (serial block-face, SBF-SEM) microscopists were able to collect large volumes of 3D EM information at resolutions that could address many important biological questions, and do so in an efficient manner. We present here some examples of 3D EM taken from the many diverse specimens that have been imaged in our core facility. We propose that the next major step forward will be to efficiently correlate functional information obtained using light microscopy (LM) with 3D EM datasets to more completely investigate the important links between cell structures and their functions.


Assuntos
Técnicas de Preparação Histocitológica/métodos , Imageamento Tridimensional/métodos , Microscopia Eletrônica de Varredura/métodos , Animais , Encéfalo/ultraestrutura , Tomografia com Microscopia Eletrônica/métodos , Pulmão/citologia , Pulmão/ultraestrutura , Camundongos , Microscopia Eletrônica , Microscopia Eletrônica de Varredura/instrumentação , Microtomia , Raízes de Plantas/ultraestrutura
4.
Sci Rep ; 14(1): 1680, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243038

RESUMO

The magnetic properties of Co(10 Å)/NiO(40 Å)/Fe trilayer epitaxially grown on W(110) substrate were investigated with use of x-ray magnetic linear dichroism (XMLD) and x-ray magnetic circular dichroism (XMCD). We showed that magnetic anisotropy of Fe film that can be controlled by a thickness-driven spin reorientation transition is transferred via interfacial exchange coupling not only to NiO layer but further to ferromagnetic Co overlayer as well. Similarly, a temperature driven spin reorientation of Fe sublayer induces a reorientation of NiO spin orientation and simultaneous switching of the Co magnetization direction. Finally, by element specific XMCD and XMLD magnetic hysteresis loop measurements we proved that external magnetic field driven reorientation of Fe and Co magnetizations as well as NiO Néel vector are strictly correlated and magnetic anisotropy fields of Fe and Co sublayers are identical despite the different crystal structures.

5.
Surf Sci ; 617(100): 183-191, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24748690

RESUMO

The adsorption of oxygen on a pseudomorphic iron monolayer deposited on a W(110) surface was studied experimentally and theoretically. Standard surface characterization methods, such as Auger electron spectroscopy and low energy electron diffraction, and specific nuclear methods, such as conversion electron Mössbauer spectroscopy (CEMS) and nuclear resonant scattering of synchrotron radiation, combined with theoretical calculations based on the density functional theory allowed us to determine the structure of the oxygen adsorbate and the electronic properties of iron atoms with different oxygen coordinations. The oxygen-(3 × 2) structure on the iron monolayer was recognized and was interpreted to be a state with oxygen chemisorbed on the non-reconstructed surface with modest electron transfer from iron to oxygen. A transition from chemisorbed oxygen to the onset of Fe-oxidation is revealed by distinct changes in the CEMS spectra.

6.
Vnitr Lek ; 59(11): 962-70, 2013 Nov.
Artigo em Tcheco | MEDLINE | ID: mdl-24279439

RESUMO

INTRODUCTION: Severe sepsis is still associated with significant morbidity and mortality, which is however different, as well as its management, depending on the region. What is the situation in the Czech Republic and what is the character of patients with severe sepsis is currently not known. The aim of the project is to describe the processes of care, outcome and characteristics of patients with severe sepsis admitted to the intensive care department of the Czech Republic. METHODS: This is a multicentre and observational project with retrospective enrollment of patients who meet the criteria for severe sepsis before or within 24 hours after admission to selected intensive care units (ICU EPOSS). RESULTS: 394 patients were analyzed. Median age at admission was 66 (56- 76) years, males predominated (58.9%) and the median APACHE II score on admission was 25 (19- 32). Patients were predominantly medical (56.9%) and most were secondary admitted from other ICU (53.6%). Meeting the criteria of severe sepsis was most frequently within the period (± 4 hours) of admission the EPOSS ICU (77.6%). Median total fluid intake during the first 24 hours was 6,680 (4,840- 9,450) ml. Most patients required mechanical ventilation (58.4%). Compliance with the resuscitation bundle of severe sepsis in our group was very good and was associated with lower mortality of patients. Most frequently, the EPOSS ICU length of stay (LOS) was 7 (3- 15) days and median hospital LOS was 13 (8- 28) days. Hospital mortality in our cohort was 35.8%. CONCLUSION: Introducing the project, which in its first stage obtained valuable and internationally comparable data about patients with severe sepsis admitted to the involved ICU in the Czech Republic.


Assuntos
Infecção Hospitalar/terapia , Unidades de Terapia Intensiva , Sepse/terapia , Adulto , Idoso , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/mortalidade , República Tcheca , Feminino , Fidelidade a Diretrizes , Mortalidade Hospitalar , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Respiração Artificial , Ressuscitação , Estudos Retrospectivos , Sepse/diagnóstico , Sepse/mortalidade
7.
Sci Rep ; 13(1): 10902, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37407653

RESUMO

We show that the interaction between ferromagnetic Fe(110) and antiferromagnetic CoO(111) sublayers can be mediated and precisely tuned by a nonmagnetic Au spacer. Our results prove that the thickness of the Fe and Au layers can be chosen to modify the effective anisotropy of the Fe layer and the strength of the exchange bias interaction between Fe and CoO sublayers. Well-defined and tailorable magnetic anisotropy of the ferromagnet above Néel temperature of the antiferromagnet is a determining factor that governs exchange bias and interfacial CoO spins orientation at low temperatures. In particular, depending on the room temperature magnetic state of Fe, the low-temperature exchange bias in a zero-field cooled system can be turned "off" or "on". The other way around, we show that exchange bias can be the dominating magnetic anisotropy source for the ferromagnet and it is feasible to induce a 90-degree rotation of the easy axis as compared to the initial, exchange bias-free easy axis orientation.

8.
Sci Rep ; 13(1): 4824, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964276

RESUMO

We report on the magnetic properties of antiferromagnetic NiO(001) thin films in epitaxially grown NiO/MgO(dMgO)/Cr/MgO(001) system for different thicknesses of MgO, dMgO. Results of X-ray Magnetic Linear Dichroism show that together with an increase of dMgO, rotation of NiO spins from in-plane towards out-of-plane direction occurs. Furthermore, we investigated how the proximity of Fe modifies the magnetic state of NiO in Fe/NiO/MgO(dMgO)/Cr/MgO(001). We proved the existence of a multidomain state in NiO as a result of competition between the ferromagnet/antiferromagnet exchange coupling and strain exerted on the NiO by the MgO buffer layer.

9.
J Phys Chem Lett ; 13(36): 8522-8528, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36067031

RESUMO

Adsorption of gases on the surface of all-bcc (Fe/Co)N superlattices drives the in-plane, 90° magnetization rotation of the bulk-like Fe(110) supporting ferromagnet. Both experimental and theoretical results prove that terminating the surface of (Fe/Co)N superlattices either by Co or by Fe switches "ON" or "OFF" the spin orientation sensitivity to adsorption. Results indicate that purely surface limited adsorption processes strongly modify the magnetic anisotropy of the entire (Fe/Co)N superlattice, which acts as a kind of "artificial" surface of the bulky Fe(110) ferromagnet. Such an artificial magnetic surface anisotropy concept not only enhances the surface contribution in classical surface-bulk competition but also provides its additional chemical sensitivity.

10.
Phys Rev Lett ; 105(2): 027206, 2010 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-20867738

RESUMO

An in-plane spin-reorientation transition occurring during the growth of epitaxial Fe films on W(110) was studied in situ by using the nuclear resonant scattering of synchrotron radiation. The spin-reorientation transition originates at the Fe/W(110) interface and proceeds via a noncollinear spin structure resembling a planar domain wall that propagates towards the surface with increasing film thickness.

11.
Vnitr Lek ; 56(3): 226-32, 2010 Mar.
Artigo em Tcheco | MEDLINE | ID: mdl-20394209

RESUMO

Incidence of myocardial dysfunction in studies with severe sepsis patients is up to two thirds of patients. On the other side, patients with normal echocardiography have some type of myocardial injury, which can be detected by elevated serum levels of troponins and natriuretic peptides. Strong prognostic value of these markers regarding morbidity and mortality of septic patients indicates an important role of this "occult" myocardial injury. Therapeutical interventions should take place only in situation in that low cardiac output is not capable to ensure metabolic demands of tissues. Nowadays, because of detrimental effects of classical inotropes, new strategies are under investigation. Namely levosimendan is promising alternative, not only related to its inotropic effects. Early diagnostics, assessment of prognosis and therapeutic strategy in patients with SMD are challenging for continuing research and for clinicians of different specialities.


Assuntos
Cardiomiopatias/diagnóstico , Cardiomiopatias/terapia , Sepse/complicações , Biomarcadores/análise , Hemodinâmica , Humanos , Prognóstico
12.
Vnitr Lek ; 56(3): 220-5, 2010 Mar.
Artigo em Tcheco | MEDLINE | ID: mdl-20394208

RESUMO

Sepsis is considered to be the major cause of morbidity and mortality of patients hospitalised in intensive care. It's defined as a systemic inflammatory response of organism to infection. Incidence of myocardial dysfunction in studies with severe sepsis patients is up to two thirds of patients. Cardiac dysfunction shows a continuum from isolated and mild diastolic dysfunction to combined severe diastolic and systolic failure of both ventricles mimicking even cardiogenic shock in some patients. Typical features of septic myocardial dysfunction (SMD) are decrease in ejection fraction (EF) with dilatation ofventricles, e.g. increase in end-diastolic volume (EDV). Reversibility of myocardial dysfunction during a period from 7 to 10 days in survivors is other typical manifestation of SMD. Hence, one can speculate that development of such a type ofSMD as a temporary protective compensatory mechanism could be advantageous for of an individual patient. A large body ofevidence about mechanisms ofSMD was described; endothelial dysfunction with consequent microcirculatory and mitochondrial dysfunction and role of circulating factors are considered to be the most important.


Assuntos
Cardiomiopatias/fisiopatologia , Sepse/complicações , Animais , Sistema Nervoso Autônomo/fisiopatologia , Cardiomiopatias/etiologia , Circulação Coronária , Citocinas/fisiologia , Endotoxinas/fisiologia , Humanos , Mitocôndrias Cardíacas/fisiologia , Miocárdio/metabolismo , Miofibrilas/fisiologia , Óxido Nítrico/fisiologia , Fator de Necrose Tumoral alfa/fisiologia
13.
Sci Rep ; 10(1): 14901, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913305

RESUMO

We show that in-plane to out-of-plane magnetization switching of a ferromagnetic layer can be driven by antiferromagnetic-ferromagnetic phase transition in a nearby FeRh system. For FeRh/Au/FeAu trilayers, the impact of the magnetic phase transition of FeRh onto the perpendicular magnetization of monoatomic FeAu superlattices is transferred across the Au spacer layer via interlayer magnetic coupling. The polar spin reorientation process of the FeAu spins driven by the magnetic phase transition in the FeRh reveals its major features; namely it is reversible and displays hysteresis.

14.
Nanoscale ; 12(35): 18091-18095, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32856646

RESUMO

We show that in a uniform thickness NiO(111)/Fe(110) epitaxial bilayer system, at given temperature near 300 K, two magnetic states with orthogonal spin orientations can be stabilized in antiferromagnetic NiO. Field-free, reversible switching between these two antiferromagnetic states is demonstrated. The observed phenomena arise from the unique combination of precisely tuned interface magnetic anisotropy, thermal hysteresis of spin reorientation transition and interfacial ferromagnet/antiferromagnet exchange coupling. The possibility of field-free switching between two magnetic states in an antiferromagnet is fundamentally interesting and can lead to new ideas in heat assisted magnetic recording technology.

15.
Nanoscale ; 12(37): 19477, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32959041

RESUMO

Correction for 'Fine tuning of ferromagnet/antiferromagnet interface magnetic anisotropy for field-free switching of antiferromagnetic spins' by M. Slezak et al., Nanoscale, 2020, DOI: 10.1039/d0nr04193a.

16.
Acta Chir Plast ; 51(3-4): 83-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20514893

RESUMO

Patients with burn trauma are always in danger of contracting an infection. Although invasive mycotic infections are not as frequent as bacterial infections, high mortality and in many cases difficult diagnostics pose a serious threat not only for neutropenic patients. In more extensive burns the status is further complicated by specifically compromised immunity. The most frequent species of micromycetes isolated in burn patients are Candida spp. and Aspergillus spp. Zygomycetes represents a relatively uncommon isolation worldwide (up to 2% of all fungi. We present a case study of a young patient with 82% TBSA (total body surface area) burns, where we isolated simultaneously 3 different types of micromycetes (Aspergillus fumigatus, Fusarium sp., Absidia sp.). Mycotic infection is understood primarily as a complication in neutropenic patients and, after prophylactic antibiotic and antimycotic administration, in extensive burn trauma patients. The case ended with the death of the patient due to severe sepsis caused by the multiresistant strain Pseudomonas aeruginosa.


Assuntos
Antifúngicos/uso terapêutico , Queimaduras/complicações , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Absidia , Adulto , Antifúngicos/administração & dosagem , Aspergilose/tratamento farmacológico , Aspergillus fumigatus , Queimaduras/microbiologia , Evolução Fatal , Feminino , Fusarium , Humanos , Mucormicose/tratamento farmacológico , Micoses/tratamento farmacológico , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa , Falha de Tratamento
17.
Bratisl Lek Listy ; 110(4): 222-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19507649

RESUMO

BACKGROUND: The objective of this study was to evaluate the impact of mild hypothermia (34-35 degrees C) on the final neurological outcome in patients after resuscitation from out-of-hospital cardiac arrest. METHODS: Forty three patients, admitted at University Hospital Brno after the out-of-hospital cardiac arrest, were included in the cohort study. The inclusion criteria were out-of-hospital cardiac arrest resulting from ventricular fibrillation or non-perfusing ventricular tachycardia as well as recovery of spontaneous circulation within 60 minutes after first symptoms. Blanketrol II (Cinncinnatti Sub Zero, USA) water mattresses were used for cooling the patients. The temperature was maintained at 34-35 degrees C for 24 hours. Favorable neurological outcome was defined as a Pittsburgh cerebral-performance category 1 (good recovery) or 2 (moderate disability) on five-category scale. RESULTS: The required temperature was reached in all patients; the cooling rate was 0.8 +/- 0.3 degrees C/hour. The time between the restoration of circulation and reaching the temperature of 35 degrees C was 119 +/- 32 minutes. The time induce the hypothermia (with the core body temperature below 35 degrees C) was 26 +/- 2 hours. Good outcome at hospital discharge was achieved in 21 out of 43 (49%) patients. Ten patients died in the hospital and two patients died after the discharge from the hospital, with the overall 6 months mortality being 28%. CONCLUSION: The study confirmed feasibility, safety and possible efficacy of the mild hypothermia (34-35 degrees C) patients after the cardiac arrest. To evaluate whether the target temperature 34-35 degrees C is as beneficial as 32-34 degrees C; a randomised controlled trial design should be used (Tab. 4, Fig. 2, Ref. 17). Full Text (Free, PDF) www.bmj.sk.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca/terapia , Hipotermia Induzida , Adulto , Idoso , Idoso de 80 Anos ou mais , Temperatura Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Sci Rep ; 9(1): 889, 2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30696928

RESUMO

Antiferromagnet/ferromagnet (AFM/FM) bilayers that display the exchange bias (EB) effect have been subjected to intensive material research, being the key elements of novel spintronics systems. In a commonly accepted picture, the antiferromagnet, considered as a rigid material due to its high anisotropy and magnetic hardness, controls the magnetic properties of the ferromagnet, such as a shift of the hysteresis loop or coercivity. We show that this AFM-FM master-slave hierarchy is not generally valid and that the influence of the ferromagnet on the magnetic anisotropy (MA) of the neighbouring antiferromagnet must be considered. Our computer simulation and experimental studies of EB in an epitaxial CoO/Fe(110) bilayer show that the ferromagnetic layer with strong uniaxial magnetic anisotropy determines the interfacial spin orientations of the neighbouring AFM layer and rotates its easy axis. This effect has a strong feedback on the EB effect experienced by the FM layer. Our results show new physics behind the EB effect, providing a route for grafting a desired anisotropy onto the AFM and for precise tailoring of EB in AFM/FM systems.

19.
Neurol Neurochir Pol ; 12(5): 609-13, 1978.
Artigo em Polonês | MEDLINE | ID: mdl-310080

RESUMO

Differential diagnosis in the material was based on the neurological and radiological findings made in 45 patients with third-ventricle tumours and 133 with subtentorial tumours. No clinical syndrome has been found which could help in reliable diagnosis concerning either of these locations of the tumour. Of decisive significance for the correct localization of tumours was ventriculography which established the diagnosis in 42 cases of third-ventricle tumours and 103 cases of subtentorial tumours. The most difficult problem was recognition of the relation of the subtentorial tumours to the brain stem since this relation could not be indicated unequivocally neither by clinical findings nor by radiological examination. This required surgical revision of the posterior fossa in most cases with suspected brain stem tumours.


Assuntos
Neoplasias do Ventrículo Cerebral/diagnóstico por imagem , Neoplasias Cranianas/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Tronco Encefálico/diagnóstico por imagem , Ventriculografia Cerebral/métodos , Fossa Craniana Posterior/diagnóstico por imagem , Diagnóstico Diferencial , Humanos
20.
Neurol Neurochir Pol ; 13(1): 59-64, 1979.
Artigo em Polonês | MEDLINE | ID: mdl-424052

RESUMO

In the light of own experience with 50 patients with brain abscesses and a survey of the literature the authors discuss the values of the surgical methods of treatment in this disease. When the radical methods are used the mortality is lowest and the incidence of recurrent abscesses is lowest, but of this treatment is likely to produce considerable neurological deficit it is better to apply conservative methods, such as puncture and drainage of the abscess. The sparing operation as a method of choice may be the first stage of treatment before radical operation in acute abscess and in patients in serious clinical condition.


Assuntos
Abscesso Encefálico/cirurgia , Doença Aguda , Adolescente , Adulto , Idoso , Doenças Cerebelares/cirurgia , Criança , Pré-Escolar , Craniotomia , Drenagem , Feminino , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Sucção
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