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1.
Nucleic Acids Res ; 40(Database issue): D445-52, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22110033

RESUMO

The Protein Data Bank in Europe (PDBe; pdbe.org) is a partner in the Worldwide PDB organization (wwPDB; wwpdb.org) and as such actively involved in managing the single global archive of biomacromolecular structure data, the PDB. In addition, PDBe develops tools, services and resources to make structure-related data more accessible to the biomedical community. Here we describe recently developed, extended or improved services, including an animated structure-presentation widget (PDBportfolio), a widget to graphically display the coverage of any UniProt sequence in the PDB (UniPDB), chemistry- and taxonomy-based PDB-archive browsers (PDBeXplore), and a tool for interactive visualization of NMR structures, corresponding experimental data as well as validation and analysis results (Vivaldi).


Assuntos
Bases de Dados de Proteínas , Proteínas/química , Gráficos por Computador , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica , Proteínas/classificação , Proteínas/ultraestrutura , Análise de Sequência de Proteína , Software
2.
Magn Reson Chem ; 48(6): 443-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20474022

RESUMO

The NMR conformational study of three asymmetric phenylindenylidene ruthenium complexes 4.1-4.3, is presented. Complete (1)H and (13)C assignments could be obtained for 4.1-4.3 in benzene solution from multiple 2D homonuclear and heteronuclear NMR techniques. Our NMR analysis shows that each complex exists as a 55:45 mixture of two rotational isomers in slow exchange on the NMR chemical shift timescale. They are shown to be related by a 180 degrees flip of the indenylidene ligand along the Ru=CR bond. Both rotational isomers can be discriminated by means of NOEs contacts between the various ligands coordinating to the Ru. By matching these stereospecific assignments to the chemical shift, a chemical shift based fingerprint of the isomers that may allow straightforward assignment of future asymmetric phenylindenylidene ruthenium complexes is proposed.

3.
Inorg Chem ; 47(13): 5831-40, 2008 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-18517195

RESUMO

A tin(IV) oxoalkoxo cluster with unprecedented architecture has been prepared and characterized by single-crystal X-ray diffraction. The cluster obeys the formula Sn 12O 8(OH) 4(OEt) 28(HOEt) 4 (1) and is based on an elongated centrosymmetric assembly of 12 six-coordinate tin centers, 28 peripheral ethoxy groups (terminal and bridging), 8 oxo bridges (mu2 and mu3), 4 hydroxy bridges (mu2), and 4 ethanol molecules that are all bound to tin atoms and interact strongly, through hydrogen bonds, with an ethoxy group located on a vicinal tin atom. This compound has also been fully characterized in solution by multinuclear 1D and 2D NMR, with all of its (119)Sn, (1)H, and (13)C NMR resonances assigned with respect to the structure. Altogether, the data allowed unambiguous location of the hydroxy groups. Information on the exchange of the ethoxy groups is also presented.

4.
JBR-BTR ; 83(6): 296-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11210681

RESUMO

Bedside chest radiographic examinations in intensive care units with grids are impaired by artefacts caused by angulation of the grid (grid cut-off). Two different grids--a grid with a high strip density of 70 lines per cm and the "InSight portable imaging system"--were examined in an intensive care unit with respect to their susceptibility to angulation, image quality and handling of the grid. Five radiologists compared 50 radiographs of each grid considering ten image quality criteria. Using the "InSight portable imaging system" major artefacts were undetectable even at an angulation of 10%; no adjustment of the grid was required, which reduced the amount of time needed to take the radiograph by 26%. The increase in dosage demanded by the employment of the grids at low kilovolt peak setting could be partially compensated by the use of high kilovolt peak setting. The image quality of the "InSight portable imaging system" together with a high kilovolt peak setting is satisfactory, and due to its simplified handling, the portable imaging system has proved to be suitable for bedside chest radiography in intensive care.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Intensificação de Imagem Radiográfica/métodos , Radiografia Torácica/métodos , Artefatos , Humanos , Unidades de Terapia Intensiva , Intensificação de Imagem Radiográfica/instrumentação , Radiografia Torácica/instrumentação , Radiometria
6.
Ultraschall Med ; 18(3): 116-23, 1997 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-9340737

RESUMO

UNLABELLED: A Direct Comparison with Percutaneous Angiography: AIM: To compare colour-coded Doppler sonography (CCDS) with conventional angiography in severe occlusive vascular disease of the lower limb. METHODS: In 55 patients 1141 vessel segments were evaluated, 700 of them with atheromatous plaques, 270 with stenoses, 208 with occlusions and 6 with aneurysms. RESULTS: Deeper-seated vessels such as the abdominal aorta, the pelvic arteries, the superficial femoral artery at the level of the adductor canal and parts of the lower leg arteries are less accessible for direct CCDS. Many pathological changes however can be diagnosed indirectly by changes in the spectral wave form distal to the lesion. In superficial vascular segments (the common femoral artery, the profunda femoris artery, the superficial femoral artery above the adductor canal and the popliteal artery) image quality was excellent, more pathological changes were found, and the degree of stenosis was better estimated in comparison to angiography. CONCLUSION: The value of CCDS in patients with intermittent claudication is limited to those who have been examined with angiography e.g. before angioplasty, to follow-up examinations after vascular dilatation or surgery and to supplementary visualisation after angiography especially in readily accessible (superficial) vascular segments.


Assuntos
Angiografia , Arteriopatias Oclusivas/diagnóstico por imagem , Isquemia/diagnóstico por imagem , Perna (Membro)/irrigação sanguínea , Ultrassonografia Doppler em Cores , Adulto , Idoso , Idoso de 80 Anos ou mais , Artérias/diagnóstico por imagem , Arteriosclerose/diagnóstico por imagem , Circulação Colateral/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Acta Anaesthesiol Belg ; 48(4): 245-50, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9526603

RESUMO

In this placebo controlled, double blind multicentre study, the efficacy and safety of a single i.v. bolus dose of ondansetron 4 mg were evaluated in the prevention of postoperative nausea and vomiting (PONV), which remains one of the most unpleasant side effects experienced by patients postoperatively. The study population included patients having general anesthesia and undergoing major gynecological or elective abdominal surgery by laparoscopy. Thirty three percent of placebo-treated patients had at least one emetic episode over 24 hrs compared with 21% in the ondansetron group (p = 0.03). Forty two percent of placebo-treated patients experienced nausea in the 24 hours post-recovery period, compared to 27% of patients treated with ondansetron 4 mg (p = 0.01). Several factors appeared to be associated with an increased risk of developing PONV, namely gender (female), type of surgery (gynecological), experience of previous PONV and duration of anesthesia; the use of propofol was not a significant factor. Ondansetron was well tolerated, with no side effect being reported as a significant problem.


Assuntos
Antieméticos/farmacologia , Náusea/prevenção & controle , Ondansetron/farmacologia , Complicações Pós-Operatórias/prevenção & controle , Vômito/prevenção & controle , Adolescente , Adulto , Idoso , Antieméticos/administração & dosagem , Antieméticos/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Injeções Intravenosas , Laparoscopia , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Ondansetron/administração & dosagem , Ondansetron/efeitos adversos , Complicações Pós-Operatórias/induzido quimicamente , Fatores de Risco , Vômito/induzido quimicamente
8.
J Belge Radiol ; 78(6): 339-41, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8576020

RESUMO

Long-term outcome and survival after emergency embolisation of life-threatening bleeding caused by non-malignant small pelvic lesions were analysed and related to the techniques and embolisation materials used. Emergency transcatheter embolisation was performed in 11 patients, heavily bleeding from uterine arteriovenous malformations (4 patients), pelvic fractures (4 patients), Endoxan induced cystitis (1 patient), haemorrhoids (1 patient) and polyposis recti (1 patient) using GAW-coils. Ethibloc and Gelfoam strips as embolisation materials, alone or in combination. Follow-up was obtained up to 7.5 years with analysis of survival. Only in one patient, with terminal hepatic insufficiency and severe disturbance of coagulation, recurrent bleeding occurred 1 month after embolisation. Two other patients died during follow-up for other reasons (cardiac insufficiency at 17 months, ileus at 52 months). Complications in relation to the embolisation therapy did not occur. In conclusion, percutaneous transcatheter embolisation is a safe and effective procedure in severe hemorrhage resulting from non-malignant lesions of the pelvis.


Assuntos
Embolização Terapêutica/métodos , Pelve/irrigação sanguínea , Hemorragia Uterina/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia , Artérias , Malformações Arteriovenosas/complicações , Malformações Arteriovenosas/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hemorragia Uterina/diagnóstico por imagem , Hemorragia Uterina/etiologia
9.
Br J Radiol ; 68(816): 1336-43, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8777595

RESUMO

Transcatheter embolization was performed in 45 patients suffering from potentially lethal bleeding originating from malignant tumours in the pelvic region. In 21 cases, the basic disease was rectosigmoidal and in 20, gynaecological in origin. Uncommon bleeding sites were embolized in four other cases. The median survival time (Kaplan-Meier) was 6 months. Most patients died from tumour cachexia. In 10 cases (22%), recurrent bleeding occurred, in three of these with lethal consequences. Successful reembolization was performed on seven patients. The different embolization materials used showed a minor impact on the therapeutic result. Embolization therapy proved to be an effective measure in potentially lethal malignant pelvic bleeding. Gianturco, Anderson and Wallace (GAW) coils should be given preference where there is urgency, as they are accurate, easily and quickly insertable, and cause few complications.


Assuntos
Embolização Terapêutica/métodos , Hemorragia/terapia , Neoplasias Pélvicas/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Emergências , Feminino , Hemorragia/etiologia , Hemorragia/mortalidade , Homeostase , Humanos , Neoplasias Intestinais/irrigação sanguínea , Neoplasias Intestinais/complicações , Neoplasias Intestinais/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasias Pélvicas/irrigação sanguínea , Neoplasias Pélvicas/mortalidade , Recidiva , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento , Neoplasias Urogenitais/irrigação sanguínea , Neoplasias Urogenitais/complicações , Neoplasias Urogenitais/mortalidade
10.
Aktuelle Radiol ; 5(5): 293-6, 1995 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-7495890

RESUMO

Bedside chest radiographic examinations in intensive care units with grids and high kilovoltage-peak settings are impaired by artifacts caused by the angulation of the grid (grid cutoff). We have tried to optimize the use of grids in bedside chest radiographic examinations. The sensitivity to the effect of grid cutoff was examined in two grids with the same grid ratio (12:1) but different numbers of lamelle per cm (40 versus 70) using a water-phantom. The alignment of the grid in a bedside setting was optimised. 100 chest examinations in the intensive care unit were compared by five radiologists according to ten criteria. Grids with a high number of lamelle per cm (70) proved to be less sensitive to the effects of grid cutoff. By positioning the grid with the lamelle vertical to patient's body-axis, asymmetric exposure of the lungs could be avoided. In addition, this setting allows an easy alignment of the grid by adjusting the grid together with the moveable part of the patient's bed. In examinations with grids, the advantages of high kilovoltage-peak setting were apparent. Bedside radiographic examinations in intensive care units with grids with a high number of lamelle and high-kilovoltage-peak setting can be performed without any major additional effort. By this method the image quality can be improved, especially in lungs with increased scatter-radiation.


Assuntos
Cuidados Críticos , Sistemas Automatizados de Assistência Junto ao Leito , Radiografia Torácica/instrumentação , Ecrans Intensificadores para Raios X , Artefatos , Humanos , Modelos Anatômicos , Garantia da Qualidade dos Cuidados de Saúde , Doses de Radiação
11.
Ultraschall Med ; 16(3): 132-9, 1995 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-7667622

RESUMO

The value of colour-coded Doppler sonography to evaluate results of percutaneous transluminal angioplasty of the superficial femoral artery was tested in 26 patients. Because of good accessibility, morphology may be demonstrated similar to intravenous DSA. However, accurate evaluation of dilatation success also requires haemodynamic measurements. Numerous parameters were determined one day before, one day after and one month after angioplasty at various points of the extremity (dilated segment, popliteal artery, lower leg arteries). Results were compared with those of normal individuals. Because of the large range of scatter and overlapping between normal and pathological values, only a few parameters can be used as valuable indicators for successful PTA. Spectral wave form becomes bi- or triphasic pattern and due to this the Pulsatility Index rises distal to the dilated area. An increasing systolic acceleration rate, peak systolic velocity and prestenotic Pulsatility Index have excellent predictive value. Using a Damping Factor, the later walking range may be predicted.


Assuntos
Angioplastia com Balão , Arteriopatias Oclusivas/diagnóstico por imagem , Coxa da Perna/irrigação sanguínea , Ultrassonografia Doppler em Cores , Adulto , Idoso , Idoso de 80 Anos ou mais , Arteriopatias Oclusivas/terapia , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Artéria Femoral/diagnóstico por imagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Pulsátil/fisiologia
12.
Ultraschall Med ; 15(6): 296-303, 1994 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-7846507

RESUMO

Statistical analysis of a group of 25 healthy individuals, examined via angiodynography, shows a large range of scatter for all measured parameters in pelvic and lower extremity arteries. Blood flow and velocity values, systolic acceleration and vessel diameter decrease whereas the pulsatility index rises from the centre towards the periphery. Problem areas for morphological and quantitative evaluation are the abdominal aorta, pelvic vessels, superficial femoral artery in the distal adductor canal and the fibular artery. Nearly all vessels showed tri- or multiphasic spectral patterns. Biphasic waveform, however, may be normal in lower extremity arteries. The data yielded by colour-coded Doppler sonography were comparable to results obtained with other procedures.


Assuntos
Perna (Membro)/irrigação sanguínea , Pelve/irrigação sanguínea , Ultrassonografia Doppler em Cores , Adolescente , Adulto , Artérias/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
13.
Rofo ; 156(3): 277-81, 1992 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-1550927

RESUMO

In order to evaluate the suitability of digital radiography for the diagnosis of skeletal abnormalities, inflammatory joint changes were used to test this technique. Early erosive changes, fine irregularities and marginal lamellar abnormalities demand a high degree of resolution from the imaging method. 6 observers studied images of the hand of 67 and of the foot of 19 patients. Joint changes were staged according to the scheme proposed by Larsen; in this study the early stages predominated. With similar techniques there were no significant differences between the digital and conventional techniques. Images of 39 large joints (knee, shoulder, elbow, ankle) were compared only subjectively since even minor differences in projection were able to obscure some erosions. However, in this case also both techniques appear to be of similar value.


Assuntos
Artrite/diagnóstico por imagem , Artrografia , Intensificação de Imagem Radiográfica , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite/classificação , Artrite Psoriásica/classificação , Artrite Psoriásica/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
14.
J Clin Ultrasound ; 20(3): 187-93, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1313832

RESUMO

Accuracy of two systems--conventional (DRF 400, Diasonics) and color-coded (Angiodynograph, Quantum/Phillips) image-directed Doppler ultrasonography--was investigated using an in vitro model that generated both monophasic and triphasic pulsatile flow patterns. Estimated and actual blood volume flow rates showed good correlations, but the sampling with a hand-held transducer led to wide variations in measurement error for the conventional (-69.2% to 50%) and the color-coded (-79.3% to 265.7%) systems. By performing multiple measurements, one could improve accuracy considering only the maximal values of a series instead of the mean values. Accuracy was impaired by interposed muscular or fatty tissue due to false low time-average velocity measurements caused by a loss of Doppler signal. Comparison of both systems revealed significant differences between pulsatility index values (p less than 0.001), blood flow velocities (p less than 0.001), and blood volume flow rates (p less than 0.05 for program flow, p less than 0.001 for manual and automatic flow program of the color-coded system).


Assuntos
Velocidade do Fluxo Sanguíneo , Ultrassonografia/métodos , Humanos , Modelos Anatômicos , Fluxo Pulsátil , Reprodutibilidade dos Testes
15.
Rofo ; 156(3): 282-5, 1992 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-1312879

RESUMO

The importance of lymphangiography for diagnosing the formation of lymphatic fistulas and vascular dysplasias of the lymphatic vessels is on the increase within the scope of therapeutic invasiveness. Its importance and ranking in diagnosing lymphatic circular disorders is demonstrated and exemplified by case reports on three patients suffering from chylothorax of various origin, on one patient with chyluria, and one patient with lymphoedema in the soft parts of the neck. In two chylothorax patients, lymphangiography resulted in successful surgery. It is the decisive method in diagnosis and therapy planning in fistulas and dysplasias of the lymphatic vessel system.


Assuntos
Fístula/diagnóstico por imagem , Doenças Linfáticas/diagnóstico por imagem , Sistema Linfático/anormalidades , Adulto , Quilo , Quilotórax/diagnóstico por imagem , Feminino , Humanos , Óleo Iodado , Linfografia , Masculino , Pessoa de Meia-Idade , Recidiva , Urina
16.
Aktuelle Radiol ; 2(1): 26-31, 1992 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-1312361

RESUMO

Cystosarcoma phylloides is characterized by frequent local recurrences, by questionable tumour status and by the often large size or extension. This very rare tumour is mentioned in the literature mostly as a case report. During 1974-1989 a group of 15 cases could be collected. Starting with the different pathological and anatomical features, the typical mammographic and sonographic criteria are described. The outline of the tumour is smooth and often lobulated. The solid component has echo levels lower than the surrounding breast tissue and is mostly homogeneous. Some parts may be cystic. Endotumoral calcifications are very rare. In all cases a zone of dorsal acoustic enhancement was seen. Differential diagnosis is discussed. In large breast tumours with slow and episodic growth, the tentative diagnosis cystosarcoma phylloides should be considered more often.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Tumor Filoide/diagnóstico por imagem , Adulto , Neoplasias da Mama/epidemiologia , Feminino , Alemanha Ocidental/epidemiologia , Humanos , Mamografia , Pessoa de Meia-Idade , Tumor Filoide/epidemiologia , Estudos Retrospectivos , Ultrassonografia
18.
Rofo ; 155(5): 442-4, 1991 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1954364

RESUMO

Between August 1984 and August 1990, 166 patients received a 22-channel cochlear implant (Nucleus) in the ENT clinic in Hannover. Some of these patients who were able to understand speech nevertheless complained of inadequate perception. To study this further a phantom skull with a cochlear implant was examined by CT and by conventional tomography of the petrous bone in various image planes. The method of choice for evaluating the position and appearance of the cochlear implant proved to be conventional tomography of the petrous bone in the frontal transorbital plane. In 7/23 patients examined it was possible to demonstrate dislocation of the electrodes; this is evidently responsible for the faulty perception.


Assuntos
Implantes Cocleares , Complicações Pós-Operatórias/diagnóstico por imagem , Percepção da Fala , Osso Temporal/diagnóstico por imagem , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Tomografia por Raios X
19.
Ultraschall Med ; 12(4): 188-92, 1991 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-1957154

RESUMO

Apart from the proximal anastomosis, aortoiliac/-femoral bypass is accessible to angiodynography. The spectral waves can mostly be derived and analyzed very well. Femoropopliteal grafts can be demonstrated over the whole length, including the anastomoses if they are not located in the adductor (Hunter's) canal. Pathological findings such as stenosis or aneurysms can be easily detected. Because of a large range of scatter, blood velocity or flow are no suitable parameter to determine functioning and prognosis of the bypass. A triphasic spectral waveform in the graft, the failing of aneurysms, stenosis or turbulent blood flow in the anastomosis, a high "Pulsatility Index" and a short systolic blood flow acceleration distal to the bypass, proved to be more important parameters, that can be easily determined via colour coded Doppler sonography.


Assuntos
Prótese Vascular , Oclusão de Enxerto Vascular/diagnóstico por imagem , Isquemia/diagnóstico por imagem , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Complicações Pós-Operatórias/diagnóstico por imagem , Adulto , Idoso , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/cirurgia , Velocidade do Fluxo Sanguíneo/fisiologia , Volume Sanguíneo/fisiologia , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Humanos , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/cirurgia , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Fluxo Pulsátil , Ultrassonografia
20.
Rofo ; 154(1): 34-8, 1991 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-1846690

RESUMO

The adductor canal was simulated using 2.6 cm muscular tissue and 2 fasciae to analyse the limits of colour-coded Doppler sonography (angiodynography) in this region. Defects in the spectral signal cause a significant underestimation of mean, peak systolic and peak diastolic (backflow) velocities and of calculated blood flow. Furthermore the pulsatility index is overestimated and the colour-coded visualisation of the arteries is almost lost. For the most part, these changes can be compensated by administration of a sonographic contrast agent (SH U 454). A minimum of 9 mg microbubbles/ml blood is required. Nevertheless, the adjustment of system controls (e.g. transducer power) becomes more difficult and an ideal setting impossible.


Assuntos
Meios de Contraste , Artéria Femoral/diagnóstico por imagem , Modelos Estruturais , Polissacarídeos , Humanos , Perna (Membro)/diagnóstico por imagem , Músculos/diagnóstico por imagem , Ultrassonografia
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