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1.
Radiologie (Heidelb) ; 2024 Jul 17.
Artículo en Alemán | MEDLINE | ID: mdl-39017722

RESUMEN

BACKGROUND: Mammography screening programs (MSP) have shown that breast cancer can be detected at an earlier stage enabling less invasive treatment and leading to a better survival rate. The considerable numbers of interval breast cancer (IBC) and the additional examinations required, the majority of which turn out not to be cancer, are critically assessed. OBJECTIVE: In recent years companies and universities have used machine learning (ML) to develop powerful algorithms that demonstrate astonishing abilities to read mammograms. Can such algorithms be used to improve the quality of MSP? METHOD: The original screening mammographies of 251 cases with IBC were retrospectively analyzed using the software ProFound AI® (iCAD) and the results were compared (case score, risk score) with a control group. The relevant current literature was also studied. RESULTS: The distributions of the case scores and the risk scores were markedly shifted to higher risks compared to the control group, comparable to the results of other studies. CONCLUSION: Retrospective studies as well as our own data show that artificial intelligence (AI) could change our approach to MSP in the future in the direction of personalized screening and could enable a significant reduction in the workload of radiologists, fewer additional examinations and a reduced number of IBCs; however, the results of prospective studies are needed before implementation.

2.
Int J Clin Pharm ; 46(3): 656-664, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38367103

RESUMEN

BACKGROUND: Limited data are available on characteristics associated with antipsychotic use in multimorbid older adults. AIM: Primary: to identify patient characteristics associated with antipsychotic prescribing in a multimorbid population of older inpatients with polypharmacy. Secondary: (1) to observe if antipsychotics use during an index hospitalisation was associated with a drug related admission (DRA) within one year, and (2) to describe these cases of antipsychotic-related readmissions. METHOD: This was a secondary analysis of the OPERAM randomized controlled trial. Multivariate analysis assessed the association between characteristics and comorbidities with antipsychotic use. An expert team assessed DRA occurring during the one-year follow-up. RESULTS: Antipsychotics were prescribed to 5.5% (n = 110) patients upon admission while 7.7% (n = 154) inpatients received antipsychotics at any time (i.e. upon admission, during hospitalisation, and/or at discharge). The most frequently prescribed antipsychotics were quetiapine (n = 152), haloperidol (n = 48) and risperidone (n = 22). Antipsychotic prescribing was associated with dementia (OR = 3.7 95%CI[2.2;6.2]), psychosis (OR = 26.2 [7.4;92.8]), delirium (OR = 6.4 [3.8;10.8]), mood disorders (OR = 2.6 [1.6;4.1]),  ≥ 15 drugs a day (OR = 1.7 [1.1;2.6]), functional dependency (Activities of Daily Living score < 50/100) (OR = 3.9 [2.5;6.1]) and < 2 units of alcohol per week (OR = 2.2 [1.4;3.6]). DRA occurred in 458 patients (22.8%) within one year. Antipsychotic prescribing at any time was not associated with DRA (OR = 1.0 [0.3;3.9]) however contributed to 8 DRAs, including 3 falls. CONCLUSION: In this European multimorbid polymedicated older inpatients, antipsychotics were infrequently prescribed, most often at low dosage. Besides neuro-psychiatric symptoms, risk factors for inhospital antipsychotic prescribing were lower functional status and polymedication.


Asunto(s)
Antipsicóticos , Readmisión del Paciente , Humanos , Antipsicóticos/uso terapéutico , Antipsicóticos/efectos adversos , Masculino , Femenino , Anciano , Anciano de 80 o más Años , Readmisión del Paciente/estadística & datos numéricos , Polifarmacia , Multimorbilidad , Hospitalización/estadística & datos numéricos , Pacientes Internos
3.
Int J Cardiol Heart Vasc ; 50: 101349, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38322018

RESUMEN

Quantitative flow ratio (QFR) is a novel, software-based noninvasive method for the quantitative evaluation of coronary physiology. QFR results correlate with invasive FFR measurements in the three main epicardial coronary arteries. However, QFR data for the evaluation of coronary side branches (SB) are scarce. The evaluation of QFR-performance of SB was retrospective and prospective. Eighty-seven patients with suspected chronic coronary syndrome, who received angiography using routine core lab projections, were retrospectively analyzed. On the second part 37 patients, who received angiography using recommended standardized coronary angiography projections, were prospectively analyzed. Quantitative analysis was performed for SB with a maximum lumen diameter proximal of ≥2 mm based on quantitative coronary angiography (QCA) by two certified experts with the software QAngio XA 3D 3.2. Using routine projections, QFR computation in 55 % of the SB were obtained (123 out of 224). Using standardized projections, 85 % of SB were computed by QFR (64 out of 75; p < 0.001 vs routine projections). The fluoroscopy time for recommended projections was not significantly different as opposed to routine projections (3.75 ± 2.2 vs. 4.58 ± 3.00 min, p = 2.6986). Using the standardized projections was associated with a higher amount of contrast medium (53.44 ± 24.23 vs. 87.95 ± 43.73 ml, p < 0.01), longer overall procedure time (23.23 ± 16.35 vs. 36.14 ± 17.21 min, p < 0.01) and a higher dose area product (1152.28 ± 576.70 vs. 2540.68 ± 1774.07 cGycm2, p < 0.01). Our study shows that the blood flow of the vast majority of coronary SB can be determined non-invasively by QFR in addition to the main epicardial coronary arteries when standardized projections are used.

4.
Mar Pollut Bull ; 195: 115561, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37734224

RESUMEN

We investigated the effects of volatile organic carbons (VOCs) evaporated from gas condensate on the cyanobacteria Synechococcus sp. WH8103, the diatom Asterionellopsis glacialis, and the dinoflagellate Alexandrium minutum. We used custom algal incubation chambers enabling only the gas condensate-derived VOCs to interact with the cell cultures via an atmospheric bridge, without direct contact with the hydrocarbon oil. The exposure to gas condensate VOCs reduced the abundance, growth rate, and photosynthetic efficiency of Synechococcus sp. WH8103. Thiobarbituric acid reactive substances (TBARS) assays hint at oxidative damage to the chloroplasts and/or the thylakoid membranes in this organism. A.glacialis abundance, physiological state and growth rates remained unchanged, whereas A.minutum abundance and photosynthetic efficiency increased relative to their respective controls. Our results demonstrate that the effects of a gas condensate formed due to an oil spill will not be restricted to the polluted area, but may be prominent in downwind locations through atmospheric transport.


Asunto(s)
Diatomeas , Dinoflagelados , Synechococcus , Fitoplancton/fisiología , Dinoflagelados/fisiología , Diatomeas/fisiología , Fotosíntesis , Carbono
5.
J Mater Sci Mater Med ; 32(9): 119, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34487244

RESUMEN

The main target of the present research was a full assessment of the toxicity effects and biocompatibility of a Ti/Al-alloy device coated with biogenic hydroxyapatite (bHA) when implanted in dogs in comparison with those of an uncoated Ti/Al-alloy device. The coating of the alloy was carried out using controlled high-velocity suspension flame spray (HVSFS) technique. Both coated and uncoated devices were implanted in dogs' femur bones for different time periods (45 days and 90 days). Bone-formation ability and healing were followed up, and blood analysis was performed, at Time zero (immediately post surgery), and then at 3 days, 45 days, and 90 days post surgery. Bone mineral density checks, radiological scans of the femur bone, and histological analysis were also conducted. The in-vivo study results proved that implantation of a device made from bHA-coated Ti/Al alloy in dogs' femur bones is completely safe. This is due to the high osteoconductivity of the coated alloy, which enables the formation of new bone and a full connection between new and original bone material. At 90 days post surgery, the coated alloy had been completely digested within the original bone; thus, it appeared as a part of the femur bone and not as a foreign body. Both the scanning electron microscopy with energy-dispersive X-ray and histology analysis findings affirmed the results. Furthermore, the blood tests indicated no toxicity effects during the 90 days of implantation.


Asunto(s)
Aluminio/química , Durapatita/química , Prótesis e Implantes , Titanio/química , Aleaciones/síntesis química , Aleaciones/química , Aleaciones/farmacología , Aluminio/farmacología , Animales , Densidad Ósea/efectos de los fármacos , Sustitutos de Huesos/síntesis química , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Materiales Biocompatibles Revestidos/síntesis química , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Perros , Durapatita/farmacología , Fémur/diagnóstico por imagen , Fémur/efectos de los fármacos , Fémur/patología , Masculino , Microscopía Electrónica de Rastreo , Oseointegración , Osteogénesis/efectos de los fármacos , Distribución Aleatoria , Propiedades de Superficie , Titanio/farmacología
6.
J Endocrinol Invest ; 44(10): 2123-2130, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33687700

RESUMEN

BACKGROUND: Insulin resistance (IR) is associated with increased risk for type 2 diabetes mellitus and cardiovascular disease. Quantifying IR is invasive and time-consuming, and thus not routinely used in clinical practice. Simple metabolic markers to predict IR exist, but have not been validated in premenopausal women or women with polycystic ovary syndrome (PCOS). OBJECTIVE: To evaluate the ability of metabolic markers to identify premenopausal women with/without PCOS who are insulin resistant. DESIGN/SETTING: Cross-sectional analysis. PARTICIPANTS: One hundred and seventy-one non-diabetic premenopausal overweight/obese women without PCOS and 71 women with PCOS. METHODS: IR was quantified by the steady-state plasma glucose during the modified insulin-suppression test. Metabolic markers (BMI, lipid/lipoprotein concentrations, and fasting glucose) were evaluated for their discriminative ability to identify IR, using area under the receiver-operating-characteristic curve (AUROC) analysis. Optimal cut-points were evaluated for predictive power. RESULTS: In the non-PCOS group, the triglyceride/HDL cholesterol ratio (TG/HDL-C) was the best marker (AUROC 0.73). Optimal diagnostic cut-point was 1.9. In the PCOS group, the TG/HDL-C ratio, cholesterol/HDL-C ratio (TC/HDL-C), and HDL-C performed well (AUROC > 0.80), with optimal cut-points for TG/HDL-C 1.3, TC/HDL-C 3.4, and HDL-C 52 mg/dL: TG/HDL-C was more sensitive, but HDL-C had a higher PPV for IR. CONCLUSION: TG/HDL-C can identify IR in premenopausal women with and/without PCOS; diagnostic cut-points differ from those of men and postmenopausal women. HDL-C is an alternative predictor in women with PCOS. These simple metabolic markers, which are standardized between labs, inexpensive, and routinely measured, can be used to tailor lifestyle and medical interventions to improve health outcomes in insulin-resistant premenopausal women.


Asunto(s)
Biomarcadores/sangre , HDL-Colesterol/sangre , Intolerancia a la Glucosa/diagnóstico , Resistencia a la Insulina , Síndrome del Ovario Poliquístico/fisiopatología , Premenopausia , Triglicéridos/sangre , Adulto , Área Bajo la Curva , Glucemia/análisis , Índice de Masa Corporal , Estudios de Casos y Controles , Estudios Transversales , Femenino , Estudios de Seguimiento , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/epidemiología , Intolerancia a la Glucosa/patología , Humanos , Masculino , Pronóstico , Curva ROC , Estados Unidos/epidemiología
7.
Ophthalmologe ; 117(9): 905-913, 2020 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-32761414

RESUMEN

BACKGROUND: At present minimum nursing staff numbers have been defined and are being implemented. In December 2019 the German Medical Association asked the German professional associations about their general experience with planning of medical personnel in hospital departments. As no structured data were available on this subject, the German Ophthalmological Society (DOG) founded a working group in March 2020 to answer this request. METHOD: In the course of several consensus meetings, the working group on personnel planning for physicians in hospitals of the DOG prepared a questionnaire on previous experiences in personnel planning of eye hospitals, which was sent to the heads of all university eye hospitals and departments of ophthalmology in Germany. The questionnaire consisted of individual items with fixed choices and free answers regarding the procedure and current situation of staffing as well as the range of tasks and organization of the medical service. RESULTS: Out of 104 departments 53 (51%) responded, of which 25 were from university departments (64% response), 23 from departments of other public or non-profit ownership (46%) and 5 from departments with private hospital ownership (33%). Of these 49% stated that there was no transparent basis for calculation of the number of medical positions in their hospital. Of the surveyed departments, outpatient tasks, services and revenues were considered in the calculations in only 47%. There was a statistically significant higher ratio of full-time personnel to the numbers of beds in university departments compared to private and publicly owned non-profit institutions (p < 0.001, t­test). All departments have to cope with multiple additional tasks in addition to clinical patient care, which are taken into account only to a limited extent in the staffing. Approximately 70% of the departments provide a 24 h/7 day (24/7) medical on-call service on site, 91% have a 24/7 surgery on-call service and 34% have a cooperation with emergency services run by the Association of Statutory Health Insurance Physicians. CONCLUSION: The results show how heterogeneously and nontransparent German departments of ophthalmology are staffed in terms of medical doctors. On average, university departments have higher personnel resources per hospital bed to cope with additional tasks in research and teaching. Outpatient tasks, which contribute significantly to the revenues of an eye department, and multiple other tasks are often not taken into account in the personnel calculation. A transparent and uniform basis for calculation of the medical staff of the departments is desirable in order to achieve a sufficient personnel staffing for a patient and employee-oriented working environment.


Asunto(s)
Oftalmología , Alemania , Departamentos de Hospitales , Humanos , Asignación de Recursos , Recursos Humanos
8.
Phys Chem Chem Phys ; 21(24): 13207-13214, 2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-31179459

RESUMEN

The local valence orbital structure of solid glycine, diglycine, and triglycine is studied using soft X-ray emission spectroscopy (XES), resonant inelastic soft X-ray scattering (RIXS) maps, and spectra calculations based on density-functional theory. Using a building block approach, the contributions of the different functional groups of the peptides are separated. Cuts through the RIXS maps furthermore allow monitoring selective excitations of the amino and peptide functional units, leading to a modification of the currently established assignment of spectral contributions. The results thus paint a new-and-improved picture of the peptide bond, enhance the understanding of larger molecules with peptide bonds, and simplify the investigation of such molecules in aqueous environment.


Asunto(s)
Modelos Químicos , Péptidos/química , Dispersión Dinámica de Luz , Electrones , Glicina/química , Glicilglicina/química , Oligopéptidos/química , Teoría Cuántica , Agua/química , Difracción de Rayos X
9.
Ophthalmologe ; 114(9): 851-856, 2017 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-28808774

RESUMEN

Refractive lenticule extraction (ReLEx/SMILE) is a refractive surgical method developed by the authors in stages primarily for correction of myopia and myopic astigmatism, in which a femtosecond laser is exclusively used. In the (ReLEx/SMILE) method a refractive lenticule is generated by the femtosecond laser, which is subsequently extracted through a small incision. Opening of the corneal surface with a flap and use of an excimer laser is no longer necessary. In 2013 the method was newly assessed and classified by the Joint Commisssion for Refractive Surgery (KRC) of the Professional Association of Ophthalmologists (BVA) and the German Ophthalmological Society (DOG). This article presents the individual stages of the technique in a video and possible errors and their avoidance are explained.


Asunto(s)
Astigmatismo/cirugía , Queratomileusis por Láser In Situ/métodos , Láseres de Excímeros/uso terapéutico , Miopía/cirugía , Corticoesteroides/administración & dosificación , Antibacterianos/administración & dosificación , Topografía de la Córnea , Humanos , Cuidados Posoperatorios/métodos , Cuidados Preoperatorios/métodos
11.
Klin Monbl Augenheilkd ; 234(1): 109-116, 2017 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-28135747

RESUMEN

In the last 20 years, the role of ultrashort pulsed lasers in ophthalmology has become increasingly important. However, it is still impossible to guide ultra-short laser pulses with standard glass fibres. The highly energetic femtosecond pulses would destroy the fibre material, and non-linear dispersion effects would significantly change beam parameters. In contrast, photonic crystal fibres mainly guide the laser pulses in air, so that absorption and dispersive pulse broadening have essentially no effect. This article compares classical beam guidance with mirrors, lenses and prisms with photonic crystal fibres and describes the underlying concepts and the current state of technology. A classical mirror arm possesses more variable optical properties, while the HCF (Hollow-Core Photonic Crystal Fibre) must be matched in terms of the laser energy and the laser spectrum. In contrast, the HCF has more advantages in respect of handling, system integration and costs. For applications based on photodisruptive laser-tissue interaction, the relatively low damage threshold of photonic crystal fibres compared to classic beam guiding systems is unacceptable. If, however, pulsed laser radiation has a sufficiently low peak intensity, e.g. as used for plasma-induced ablation, photonic crystal fibres can definitely be considered as an alternative solution to classic beam guidance.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Terapia por Láser/instrumentación , Rayos Láser , Lentes , Procedimientos Quirúrgicos Oftalmológicos/instrumentación , Refractometría/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Procedimientos Quirúrgicos Refractivos/instrumentación , Dispersión de Radiación
12.
Klin Monbl Augenheilkd ; 234(1): 117-122, 2017 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-28135748

RESUMEN

The clinical use of femtosecond lasers has led to significant progress in the quality of refractive surgery. SMILE femtosecond laser surgery (SMILE: Small Incision Lenticule Extraction) permits the first one step intrastromal laser procedure without a flap. This article describes the gradual development of this surgery during the last ten years.


Asunto(s)
Cirugía Laser de Córnea/tendencias , Procedimientos Quirúrgicos Mínimamente Invasivos/tendencias , Errores de Refracción/diagnóstico , Errores de Refracción/terapia , Medicina Basada en la Evidencia , Femenino , Humanos , Masculino , Resultado del Tratamiento , Agudeza Visual
13.
J Phys Chem A ; 120(14): 2260-7, 2016 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-27003748

RESUMEN

The electronic structure of gas-phase methanol molecules (H3COH, H3COD, and D3COD) at atmospheric pressure was investigated using resonant inelastic soft X-ray scattering (RIXS) at the O K and C K edges. We observe strong changes of the relative emission intensities of all valence orbitals as a function of excitation energy, which can be related to the symmetries of the involved orbitals causing an angularly anisotropic RIXS intensity. Furthermore, all observed emission lines are subject to strong spectator shifts of up to -0.9 eV at the O K edge and up to -0.3 eV at the C K edge. At the lowest O K resonance, we find clear evidence for dissociation of the methanol molecule on the time scale of the RIXS process, which is illustrated by comparing X-ray emission spectra of regular and deuterated methanol.

14.
Geburtshilfe Frauenheilkd ; 75(6): 588-596, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26166840

RESUMEN

Introduction: Use of hormone therapy (HT) has declined dramatically in recent years. Some studies have reported that HT use before a diagnosis of breast cancer (BC) may be a prognostic factor in postmenopausal patients. This study aimed to examine the prognostic relevance of HT use before BC diagnosis. Methods: Four BC cohort studies in Germany were pooled, and 4492 postmenopausal patients with HT use data were identified. Patient data and tumor characteristics were compared between users and nonusers, along with overall survival (OS), distant metastasis-free survival (DMFS), and local recurrence-free survival (LRFS). Cox proportional hazards models were stratified by study center and adjusted for age at diagnosis, tumor stage, grading, nodal status, and hormone receptors. Results: Women with HT use before the diagnosis of BC were more likely to have a lower tumor stage, to be estrogen receptor-negative, and to have a lower grading. With regard to prognosis there were effects seen for OS, DMFS and LRFS, specifically in the subgroup of women with a positive hormone receptor. In these subgroups, BC patients had a better prognosis with previous HT use. Conclusions: HT use before a diagnosis of BC is associated with a more favorable prognosis in women with a positive hormone receptor status. It may be recommended that the prognostic factor HT should be documented and analyzed as a confounder for prognosis in studies of postmenopausal hormone-responsive breast cancers.

15.
Klin Monbl Augenheilkd ; 232(1): 67-71, 2015 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-25272083

RESUMEN

BACKGROUND: This clinical trial is focused on the 12-month results of a new method for refractive correction in myopia, called "small incision lenticule extraction" (SMILE). PATIENTS AND METHODS: In a prospective study 91 eyes were treated with the new refractive procedure and the results were published after 6 months. A lenticule of intrastromal corneal tissue is cut utilising the Carl Zeiss Meditec AG (Jena, Germany) VisuMax femtosecond laser system. Thereafter, this lenticule is manually removed without lifting a flap. 55 eyes of 33 patients volunteered for a 12-month follow-up. UCVA and BSCVA after 12 months, objective and manifest refraction as well as slit-lamp examination and late side effects were documented. RESULTS: 55 eyes of 33 patients were re-examined in this study 12 months after surgery. The spherical equivalent before surgery was - 4.66 (± 1.75) D; after 12 months - 0.11 (± 0.42) D was manifest. No significant change was observed compared to the 6-month control. Starting with UCVA of 0.1 (± 0.06) before surgery. UCVA was 1.02 (± 0.3) after 12 months. One eye lost more than two lines. All other patients did not have any late side effects. CONCLUSION: The one-year results of this new procedure are encouraging. Especially stability of the correction of myopia and myopic astigmatism with the SMILE procedure is very good.


Asunto(s)
Terapia por Láser/métodos , Miopía/diagnóstico , Miopía/cirugía , Procedimientos Quirúrgicos Refractivos/métodos , Agudeza Visual , Adulto , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos , Resultado del Tratamiento , Adulto Joven
16.
J Phys Chem B ; 118(46): 13142-50, 2014 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-25341188

RESUMEN

The electronic structure of the amino acid L-cysteine in an aqueous environment was studied using resonant inelastic soft X-ray scattering (RIXS) in a 2D map representation and analyzed in the framework of a "building block" approach. The element selectivity of RIXS allows a local investigation of the electronic structure of the three functional groups of cysteine, namely, the carboxyl, amino, and thiol groups, by measuring at the O K, N K, and S L2,3 edges, respectively. Variation of the pH value allows an investigation of molecules with protonated and deprotonated functional groups, which can then be compared with simple reference molecules that represent the isolated functional groups. We find that such building blocks can provide an excellent description of X-ray emission spectroscopy (XES) and RIXS spectra, but only if all nearest-neighbor atoms are included. This finding is analogous to the building block principle commonly used in X-ray absorption spectroscopy. The building blocks show a distinct spectral character (fingerprint) and allow a comprehensive interpretation of the cysteine spectra. This simple approach opens the path to investigate the electronic structure of more complex biological molecules in aqueous solutions using XES and RIXS.


Asunto(s)
Cisteína/química , Electrones , Concentración de Iones de Hidrógeno , Modelos Químicos , Teoría Cuántica , Espectrometría por Rayos X , Agua/química
17.
Rev Sci Instrum ; 85(1): 015119, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24517824

RESUMEN

We present a novel gas cell designed to study the electronic structure of gases and gas/solid interfaces using soft x-ray emission and absorption spectroscopies. In this cell, the sample gas is separated from the vacuum of the analysis chamber by a thin window membrane, allowing in situ measurements under atmospheric pressure. The temperature of the gas can be regulated from room temperature up to approximately 600 °C. To avoid beam damage, a constant mass flow can be maintained to continuously refresh the gaseous sample. Furthermore, the gas cell provides space for solid-state samples, allowing to study the gas/solid interface for surface catalytic reactions at elevated temperatures. To demonstrate the capabilities of the cell, we have investigated a TiO2 sample behind a mixture of N2 and He gas at atmospheric pressure.

19.
J Chem Phys ; 138(3): 034306, 2013 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-23343275

RESUMEN

Resonant inelastic soft x-ray scattering (RIXS) was used to study the electronic structure of solid cysteine films. A RIXS map approach, i.e., plotting the x-ray emission intensity as a function of excitation and emission energy, allows us to separate the contributions of the three chemically non-equivalent carbon atoms in cysteine. In particular, we can identify orbitals localized near the photoexcited atoms, as well as orbitals that are delocalized over the entire molecule.


Asunto(s)
Carbono/química , Cisteína/química , Dispersión de Radiación , Rayos X
20.
Ann Oncol ; 24(5): 1262-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23247658

RESUMEN

BACKGROUND: Chemoradiation followed by surgery is the preferred treatment of localized gastroesophageal cancer (GEC). Surgery causes considerable life-altering consequences and achievement of clinical complete response (clinCR; defined as postchemoradiation [but presurgery] endoscopic biopsy negative for cancer and positron emission tomographic (PET) scan showing physiologic uptake) is an enticement to avoid/delay surgery. We examined the association between clinCR and pathologic complete response (pathCR). PATIENTS AND METHODS: Two hundred eighty-four patients with GEC underwent chemoradiation and esophagectomy. The chi-square test, Fisher exact test, t-test, Kaplan-Meier method, and log-rank test were used. RESULTS: Of 284 patients, 218 (77%) achieved clinCR. However, only 67 (31%) of the 218 achieved pathCR. The sensitivity of clinCR for pathCR was 97.1% (67/69), but the specificity was low (29.8%; 64/215). Of the 66 patients who had less than a clinCR, only 2 (3%) had a pathCR. Thus, the rate of pathCR was significantly different in patients with clinCR than in those with less than a clinCR (P < 0.001). CONCLUSIONS: clinCR is not highly associated with pathCR; the specificity of clinCR for pathCR is too low to be used for clinical decision making on delaying/avoiding surgery. Surgery-eligible GEC patients should be encouraged to undergo surgery following chemoradiation despite achieving a clinCR.


Asunto(s)
Quimioradioterapia , Neoplasias Esofágicas/terapia , Neoplasias Gástricas/terapia , Estudios de Cohortes , Terapia Combinada , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Inducción de Remisión , Estudios Retrospectivos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/radioterapia , Neoplasias Gástricas/cirugía , Resultado del Tratamiento
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