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1.
Nucleic Acids Res ; 40(Database issue): D445-52, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22110033

RESUMEN

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).


Asunto(s)
Bases de Datos de Proteínas , Proteínas/química , Gráficos por Computador , Modelos Moleculares , Resonancia Magnética Nuclear Biomolecular , Conformación Proteica , Proteínas/clasificación , Proteínas/ultraestructura , Análisis de Secuencia de Proteína , Programas Informáticos
2.
Magn Reson Chem ; 48(6): 443-9, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20474022

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-18517195

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-11210681

RESUMEN

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.


Asunto(s)
Sistemas de Atención de Punto , Intensificación de Imagen Radiográfica/métodos , Radiografía Torácica/métodos , Artefactos , Humanos , Unidades de Cuidados Intensivos , Intensificación de Imagen Radiográfica/instrumentación , Radiografía Torácica/instrumentación , Radiometría
6.
Ultraschall Med ; 18(3): 116-23, 1997 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-9340737

RESUMEN

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.


Asunto(s)
Angiografía , Arteriopatías Oclusivas/diagnóstico por imagen , Isquemia/diagnóstico por imagen , Pierna/irrigación sanguínea , Ultrasonografía Doppler en Color , Adulto , Anciano , Anciano de 80 o más Años , Arterias/diagnóstico por imagen , Arteriosclerosis/diagnóstico por imagen , Circulación Colateral/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Acta Anaesthesiol Belg ; 48(4): 245-50, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9526603

RESUMEN

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.


Asunto(s)
Antieméticos/farmacología , Náusea/prevención & control , Ondansetrón/farmacología , Complicaciones Posoperatorias/prevención & control , Vómitos/prevención & control , Adolescente , Adulto , Anciano , Antieméticos/administración & dosificación , Antieméticos/efectos adversos , Método Doble Ciego , Femenino , Humanos , Inyecciones Intravenosas , Laparoscopía , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Ondansetrón/administración & dosificación , Ondansetrón/efectos adversos , Complicaciones Posoperatorias/inducido químicamente , Factores de Riesgo , Vómitos/inducido químicamente
8.
J Belge Radiol ; 78(6): 339-41, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8576020

RESUMEN

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.


Asunto(s)
Embolización Terapéutica/métodos , Pelvis/irrigación sanguínea , Hemorragia Uterina/terapia , Adulto , Anciano , Anciano de 80 o más Años , Angiografía , Arterias , Malformaciones Arteriovenosas/complicaciones , Malformaciones Arteriovenosas/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hemorragia Uterina/diagnóstico por imagen , Hemorragia Uterina/etiología
9.
Br J Radiol ; 68(816): 1336-43, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8777595

RESUMEN

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.


Asunto(s)
Embolización Terapéutica/métodos , Hemorragia/terapia , Neoplasias Pélvicas/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Causas de Muerte , Urgencias Médicas , Femenino , Hemorragia/etiología , Hemorragia/mortalidad , Homeostasis , Humanos , Neoplasias Intestinales/irrigación sanguínea , Neoplasias Intestinales/complicaciones , Neoplasias Intestinales/mortalidad , Masculino , Persona de Mediana Edad , Neoplasias Pélvicas/irrigación sanguínea , Neoplasias Pélvicas/mortalidad , Recurrencia , Análisis de Supervivencia , Tasa de Supervivencia , Resultado del Tratamiento , Neoplasias Urogenitales/irrigación sanguínea , Neoplasias Urogenitales/complicaciones , Neoplasias Urogenitales/mortalidad
10.
Aktuelle Radiol ; 5(5): 293-6, 1995 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-7495890

RESUMEN

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.


Asunto(s)
Cuidados Críticos , Sistemas de Atención de Punto , Radiografía Torácica/instrumentación , Pantallas Intensificadoras de Rayos X , Artefactos , Humanos , Modelos Anatómicos , Garantía de la Calidad de Atención de Salud , Dosis de Radiación
11.
Ultraschall Med ; 16(3): 132-9, 1995 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-7667622

RESUMEN

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.


Asunto(s)
Angioplastia de Balón , Arteriopatías Oclusivas/diagnóstico por imagen , Muslo/irrigación sanguínea , Ultrasonografía Doppler en Color , Adulto , Anciano , Anciano de 80 o más Años , Arteriopatías Oclusivas/terapia , Velocidad del Flujo Sanguíneo/fisiología , Femenino , Arteria Femoral/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Flujo Pulsátil/fisiología
12.
Ultraschall Med ; 15(6): 296-303, 1994 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-7846507

RESUMEN

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.


Asunto(s)
Pierna/irrigación sanguínea , Pelvis/irrigación sanguínea , Ultrasonografía Doppler en Color , Adolescente , Adulto , Arterias/diagnóstico por imagen , Velocidad del Flujo Sanguíneo/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia
13.
Rofo ; 156(3): 277-81, 1992 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-1550927

RESUMEN

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.


Asunto(s)
Artritis/diagnóstico por imagen , Artrografía , Intensificación de Imagen Radiográfica , Adulto , Anciano , Anciano de 80 o más Años , Artritis/clasificación , Artritis Psoriásica/clasificación , Artritis Psoriásica/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC
14.
J Clin Ultrasound ; 20(3): 187-93, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1313832

RESUMEN

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).


Asunto(s)
Velocidad del Flujo Sanguíneo , Ultrasonografía/métodos , Humanos , Modelos Anatómicos , Flujo Pulsátil , Reproducibilidad de los Resultados
15.
Rofo ; 156(3): 282-5, 1992 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-1312879

RESUMEN

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.


Asunto(s)
Fístula/diagnóstico por imagen , Enfermedades Linfáticas/diagnóstico por imagen , Sistema Linfático/anomalías , Adulto , Quilo , Quilotórax/diagnóstico por imagen , Femenino , Humanos , Aceite Yodado , Linfografía , Masculino , Persona de Mediana Edad , Recurrencia , Orina
17.
Aktuelle Radiol ; 2(1): 26-31, 1992 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-1312361

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Tumor Filoide/diagnóstico por imagen , Adulto , Neoplasias de la Mama/epidemiología , Femenino , Alemania Occidental/epidemiología , Humanos , Mamografía , Persona de Mediana Edad , Tumor Filoide/epidemiología , Estudios Retrospectivos , Ultrasonografía
18.
Rofo ; 155(5): 442-4, 1991 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-1954364

RESUMEN

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.


Asunto(s)
Implantes Cocleares , Complicaciones Posoperatorias/diagnóstico por imagen , Percepción del Habla , Hueso Temporal/diagnóstico por imagen , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Tomografía por Rayos X
19.
Ultraschall Med ; 12(4): 188-92, 1991 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-1957154

RESUMEN

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.


Asunto(s)
Prótesis Vascular , Oclusión de Injerto Vascular/diagnóstico por imagen , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Pierna/irrigación sanguínea , Complicaciones Posoperatorias/diagnóstico por imagen , Adulto , Anciano , Aorta Abdominal/diagnóstico por imagen , Aorta Abdominal/cirugía , Velocidad del Flujo Sanguíneo/fisiología , Volumen Sanguíneo/fisiología , Femenino , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/cirugía , Humanos , Arteria Ilíaca/diagnóstico por imagen , Arteria Ilíaca/cirugía , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Flujo Pulsátil , Ultrasonografía
20.
Rofo ; 154(1): 34-8, 1991 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-1846690

RESUMEN

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.


Asunto(s)
Medios de Contraste , Arteria Femoral/diagnóstico por imagen , Modelos Estructurales , Polisacáridos , Humanos , Pierna/diagnóstico por imagen , Músculos/diagnóstico por imagen , Ultrasonografía
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