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1.
Psychother Res ; 32(4): 415-427, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34261407

RESUMEN

AbstractPremature discontinuation from behavioral health treatment is a major problem reducing effectiveness of care in military populations. A training was developed and delivered to 622 behavioral health providers across 15 sites within the Army behavioral healthcare system. The training taught two techniques to foster treatment engagement: (1) Progress Informed Treatment, consisting of reviewing symptom assessments and outcome measures, and (2) assessment and discussion of the treatment alliance via a paper survey given near the end of each session. Eighty-five percent of providers indicated the training was useful and 89% of providers incorporated a technique into their practice. Dropout before the fourth session was significantly reduced in the six months following training, from 72.5% to 67.1% in Service Members (SM; X2(1, N=9127) = 39.58, p < .001). In both the pre and post-training periods, providers working at the Master's level, SM aged 17 or 46 or older, and clients receiving a mood, PTSD, anxiety, adjustment, substance or childhood/adolescent psychiatric diagnosis experienced significantly less dropout, while SM aged 18-21 had significantly more dropout. This training is a feasible and available option to increase treatment engagement and improve treatment outcomes for service members.


Asunto(s)
Trastornos Mentales , Personal Militar , Alianza Terapéutica , Adolescente , Niño , Humanos , Trastornos Mentales/terapia , Encuestas y Cuestionarios , Resultado del Tratamiento
2.
Tech Coloproctol ; 22(4): 305-311, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29603042

RESUMEN

Rectovaginal fistulae (RVF) are not uncommonly seen by the colorectal surgeon and gynaecologist, often debilitating for patients and typically managed with multiple operative procedures, achieving control rather than cure. Transvaginal repair is the least common surgical approach but has clear advantages and equivalent healing rates to other approaches. Here, we describe a simple, safe and effective flapless transvaginal technique for the repair of primary and recurrent low- and mid-level RVF of varying aetiology. We report 15 cases of RVF (nine recurrent) treated by this technique at a single UK centre. The healing rate was 67%. There were no major complications. Median follow-up was 48 months.


Asunto(s)
Fístula Rectovaginal/cirugía , Vagina/cirugía , Adulto , Anciano , Cirugía Colorrectal , Femenino , Humanos , Persona de Mediana Edad , Cirujanos , Resultado del Tratamiento , Reino Unido
3.
Tech Coloproctol ; 22(7): 545-551, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30022331

RESUMEN

BACKGROUND: Botulinum toxin injected into the internal anal sphincter is used in the treatment of chronic anal fissure but there is no standardised technique for its administration. This randomised single centre trial compares bilateral (either side of fissure) to unilateral injection. METHODS: Participants were randomised to receive bilateral (50 + 50 units) or unilateral (100 units) Dysport® injections into the internal anal sphincter in an outpatient setting. Injection-related pain assessed by visual analogue scale was the primary outcome measure. Secondary outcomes were healing rate, fissure pain, incontinence, and global health scores. RESULTS: Between October 2008 and April 2012, 100 patients with chronic anal fissure were randomised to receive bilateral or unilateral injections. Injection-related pain was comparable in both groups. There was no difference in healing rate. Initially, there was greater improvement in fissure pain in the bilateral group but at 1 year the unilateral group showed greater improvement. Cleveland Clinic Incontinence score was lower in the unilateral group in the early post-treatment period and global health assessment (EuroQol EQ-VAS) was higher in the unilateral group at 1 year. CONCLUSIONS: Injection-related pain was similar in bilateral and unilateral injection groups. Unilateral injection was as effective as bilateral injections in healing and improving fissure pain without any deterioration in continence.


Asunto(s)
Inhibidores de la Liberación de Acetilcolina/administración & dosificación , Toxinas Botulínicas Tipo A/administración & dosificación , Fisura Anal/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Canal Anal , Enfermedad Crónica , Femenino , Humanos , Inyecciones/efectos adversos , Inyecciones/métodos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Asociado a Procedimientos Médicos/etiología , Resultado del Tratamiento , Adulto Joven
4.
Mol Psychiatry ; 21(2): 198-204, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25824298

RESUMEN

Gamma-butyric acid (GABA) dysfunction has been implicated in the pathophysiology of schizophrenia and its cognitive deficits. Proton magnetic resonance spectroscopy (MRS) was used to test the hypothesis that older participants with schizophrenia have lower anterior cingulate GABA levels compared with older control participants. One-hundred forty-five participants completed this study. For detection of GABA, spectra were acquired from the medial frontal/anterior cingulate cortex using a macromolecule-suppressed MEGA-PRESS sequence. Patients were evaluated for psychopathology and all participants completed neuropsychological tests of working memory, processing speed and functional capacity. GABA levels were significantly lower in the older participants with schizophrenia (n=31) compared with the older control (n=37) group (P=0.003) but not between the younger control (n=40) and schizophrenia (n=29) groups (P=0.994). Age strongly predicted GABA levels in the schizophrenia group accounting for 42% of the variance, but the effect of age was less in the control group accounting for 5.7% of the variance. GABA levels were specifically related to working memory but not processing speed performance, functional capacity, or positive or negative symptom severity. This is the largest MRS study of GABA in schizophrenia and the first to examine GABA without macromolecule contamination, a potentially significant issue in previous studies. GABA levels more rapidly declined with advancing age in the schizophrenia compared with the control group. Interventions targeted at halting the decline or increasing GABA levels may improve functional outcomes and quality of life as patients with schizophrenia age.


Asunto(s)
Esquizofrenia/patología , Ácido gamma-Aminobutírico/metabolismo , Ácido gamma-Aminobutírico/fisiología , Adulto , Factores de Edad , Estudios de Casos y Controles , Trastornos del Conocimiento/patología , Femenino , Lóbulo Frontal/patología , Giro del Cíngulo/patología , Humanos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/métodos , Masculino , Memoria a Corto Plazo/fisiología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Calidad de Vida
5.
Artículo en Inglés | MEDLINE | ID: mdl-38902119

RESUMEN

AIMS: Prognosis of locally advanced pancreatic cancer (LAPC) remains poor with limited therapeutic options. Radiation therapy in pancreatic cancer has been restricted by the disease's proximity to radiosensitive organs at risk (OAR). However, stereotactic magnetic resonance-guided adaptive radiation therapy (SMART) has demonstrated promise in delivering ablative doses safely. We sought to report clinical outcomes from a UK-based Compassionate Access Programme that provided access to SMART to patients with LAPC. MATERIALS AND METHODS: This was a registry retrospective study conducted at a single centre with access to SMART. Patients with LAPC were treated with prescription dose of 40 Gy in 5 fractions. The planning objective was that 98% of PTV received ≥95% of the prescribed dose, prioritising duodenal, stomach and bowel UK SABR consortium constraints. Daily online adaptation was performed using magnetic resonance guidance and on-table re-optimisation. 0-3 months and > 3-month post-treatment-related toxicities, local progression-free survival, metastatic-free survival and overall survival were evaluated. RESULTS: 55 patients were treated with SMART at our institution from 2020 to 2022. Median follow-up from date of diagnosis was 17 months (range 5-37 months). Median age was 69.87% of patients underwent induction chemotherapy. 71% of patients reported 0-1 grade acute toxicity only. No grade >3 acute toxicity was reported. 5 patients (9%) reported a grade 3 toxicity (fatigue, nausea, abdominal pain, duodenal stricture). No grade >3 toxicity after 3 months was reported. 6 (10%) of patients had grade 3 toxicity (fatigue, nausea, abdominal pain, duodenal haemorrhage). Median local PFS post diagnosis was 17 months (95% CI 15.3-18.7). Median OS post diagnosis was 19 months (95% CI 15.9-22.1). One-year local control post SMART was 65%. CONCLUSION: This is the first UK-reported experience of MR-guided daily adaptive pancreatic SABR. SMART shows promise in delivering ablative doses with acceptable toxicity rates and good clinical outcomes.

6.
Opt Express ; 21(23): 28019-28, 2013 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-24514315

RESUMEN

Characterization of microscopic structural order and in particular medium range order (MRO) in amorphous materials is challenging. A new technique is demonstrated that allows analysis of MRO using X-rays. Diffraction data were collected from a sample consisting of densely packed polystyrene-latex micro-spheres. Ptychography is used to reconstruct the sample transmission function and fluctuation microscopy applied to characterize structural order producing a detailed `fluctuation map' allowing analysis of the sample at two distinct length scales. Independent verification is provided via X-ray diffractometry. Simulations of dense random packing of spheres have also been used to explore the origin of the structural order measured.

7.
East Mediterr Health J ; 19(6): 576-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24975188

RESUMEN

Conductive electronic devices (CED), such as Taser and stun guns, are sold worldwide for use by security services, although they have also been used for self-defence and even for torture. CED are promoted as non-lethal weapons which can potentially save lives. However, there are multiple reports of deaths temporally associated with CED use. These weapons have definite physiological effects in normal volunteers, especially when accompanied by exertion. Medical examiners often report that deaths followed physical encounters which included the use of CED were due to natural causes, excited delirium and/or drug intoxication. These cases present complex situations in which multiple factors potentially contribute to the death, including electric shocks which cause neuromuscular incapacitation, severe pain and anxiety. Public health officials, physicians and hospital personnel need to be aware that individuals controlled with CED are at increased risk of death. We need better recording of incidents worldwide to understand the extent and outcomes of CED use.


Asunto(s)
Causas de Muerte , Lesiones por Armas Conductoras de Energía/mortalidad , Conductividad Eléctrica/efectos adversos , Lesiones por Armas Conductoras de Energía/fisiopatología , Lesiones por Armas Conductoras de Energía/prevención & control , Diseño de Equipo , Seguridad de Equipos , Humanos , Aplicación de la Ley/métodos , Estados Unidos/epidemiología
8.
Breast ; 67: 55-61, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36603414

RESUMEN

PURPOSE: In March 2020, a 1-week adjuvant breast radiotherapy schedule, 26 Gy in 5 fractions, was adopted to reduce the risk of COVID19 for staff and patients. This study quantifies acute toxicity rates and the effect on linac capacity. MATERIALS AND METHODS: This is a report of consecutive patients receiving ultrafractionated breast radiotherapy ( ± sequential boost) Mar-Aug 2020. Virtual consultations assessed acute skin toxicity during treatment and weeks 1, 2, 3 and 4 post treatment using CTCAE V5 scoring criteria. The number of linac minutes saved was estimated accounting for boost and DIBH use. RESULTS: In total, 128/135 (95%) patients, including 31/33 boost patients, completed at least 3/5 assessments. 0/128 (0%) reported moist desquamation not confined to skin folds or minor bleeding (Grade 3), 41/128 (32%) reported brisk erythema, moist desquamation confined to skin folds or breast swelling (Grade 2), 62/128 (48%) reported faint erythema or dry desquamation (Grade 1) as their worst skin toxicity, with the remaining 20% reporting no skin toxicity. The highest prevalence of grade 2 toxicity occurred week 1 following treatment (20%), reducing to 3% by week 4. There was no difference in toxicity between those who received a boost versus not (p = 1.00). Delivering this schedule to 135 patients over six months saved 21,300 linac minutes and 1485 hospital visits compared to a 3-week schedule. CONCLUSION: Rapidly implementing ultrahypofractionated breast radiotherapy is feasible and acute toxicity rates are acceptable even when followed by boost.


Asunto(s)
Neoplasias de la Mama , COVID-19 , Humanos , Femenino , Radioterapia Adyuvante/efectos adversos , Neoplasias de la Mama/cirugía , Estudios Prospectivos , COVID-19/prevención & control , Mastectomía Segmentaria
9.
Opt Express ; 20(16): 18287-96, 2012 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-23038378

RESUMEN

Scanning X-ray fluorescence microscopy (XFM) is a particularly useful method for studying the spatial distribution of trace metals in biological samples. Here we demonstrate the utility of combining coherent diffractive imaging (CDI) with XFM for imaging biological samples to simultaneously produce high-resolution and high-contrast transmission images and quantitative elemental maps. The reconstructed transmission function yields morphological details which contextualise the elemental maps. We report enhancement of the spatial resolution in both the transmission and fluorescence images beyond that of the X-ray optics. The freshwater diatom Cyclotella meneghiniana was imaged to demonstrate the benefits of combining these techniques that have complementary contrast mechanisms.

10.
Opt Express ; 20(22): 24678-85, 2012 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-23187230

RESUMEN

We demonstrate Fresnel Coherent Diffractive Imaging (FCDI) tomography in the X-ray regime. The method uses an incident X-ray illumination with known curvature in combination with ptychography to overcome existing problems in diffraction imaging. The resulting tomographic reconstruction represents a 3D map of the specimen's complex refractive index at nano-scale resolution. We use this technique to image a lithographically fabricated glass capillary, in which features down to 70nm are clearly resolved.

11.
Colorectal Dis ; 14(10): 1224-30, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22251617

RESUMEN

AIM: Accurate and reliable imaging of pelvic floor dynamics is important for tailoring treatment in pelvic floor disorders; however, two imaging modalities are available. Barium proctography (BaP) is widely used, but involves a significant radiation dose. Magnetic resonance (MR) proctography allows visualization of all pelvic midline structures but patients are supine. This project investigates whether there are measurable differences between BaP and MR proctography. Patient preference for the tests was also investigated. METHODS: Consecutive patients referred for BaP were invited to participate (National Research Ethics Service approved). Participants underwent BaP in Poole and MR proctography in Dorchester. Proctograms were reported by a consultant radiologist with pelvic floor subspecialization. RESULTS: A total of 71 patients were recruited. Both tests were carried out on 42 patients. Complete rectal emptying was observed in 29% (12/42) on BaP and in 2% (1/42) on MR proctography. Anismus was reported in 29% (12/42) on BaP and 43% (18/42) on MR proctography. MR proctography missed 31% (11/35) of rectal intussusception detected on BaP. In 10 of these cases no rectal evacuation was achieved during MR proctography. The measure of agreement between grade of rectal intussusception was fair (κ=0.260) although MR proctography tended to underestimate the grade. Rectoceles were extremely common but clinically relevant differences in size were evident. Patients reported that they found MR proctography less embarrassing but harder to empty their bowel. CONCLUSIONS: The results demonstrate that MR proctography under-reports pelvic floor abnormalities especially where there has been poor rectal evacuation.


Asunto(s)
Bario , Medios de Contraste , Defecografía/métodos , Imagen por Resonancia Magnética/métodos , Trastornos del Suelo Pélvico/diagnóstico , Recto/diagnóstico por imagen , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Intususcepción/diagnóstico , Intususcepción/etiología , Masculino , Persona de Mediana Edad , Prioridad del Paciente/estadística & datos numéricos , Trastornos del Suelo Pélvico/complicaciones , Enfermedades del Recto/diagnóstico , Enfermedades del Recto/etiología , Rectocele/diagnóstico , Rectocele/etiología , Recto/fisiopatología , Método Simple Ciego , Encuestas y Cuestionarios
12.
Occup Med (Lond) ; 62(7): 578-80, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22949585

RESUMEN

BACKGROUND: Chronic carbon black exposure in the work environment can cause both respiratory symptoms and changes in lung function. There is limited information on the respiratory effects of acute exposure to carbon black. METHODS: Case report and literature review. RESULTS: A 44-year-old man had intense exposure to carbon black when his crane ran into a truck with a trailer filled with carbon black. One week after this exposure he developed shortness of breath and cough with sputum production. These symptoms persisted and increased in intensity. Physical examination revealed expiratory wheezes when in the supine position. Pulmonary function tests revealed a mild obstructive ventilatory defect with a reduced FEV(1)/FVC ratio. The patient responded to treatment with fluticasone and salmeterol with a reduction in symptoms and improvement in his spirometry to a normal range. CONCLUSIONS: Acute exposure to carbon black can cause respiratory symptoms and an obstructive ventilatory defect. This presentation suggests a small airway disease which improved over time with inhaled steroids and long-acting beta-agonists. Patients with intense carbon black exposure following industrial accidents will need frequent evaluation to manage any related respiratory tract injury.


Asunto(s)
Albuterol/análogos & derivados , Androstadienos/uso terapéutico , Broncodilatadores/uso terapéutico , Enfermedades Profesionales/tratamiento farmacológico , Exposición Profesional/efectos adversos , Trastornos Respiratorios/tratamiento farmacológico , Hollín/efectos adversos , Accidentes de Trabajo , Adulto , Albuterol/uso terapéutico , Fluticasona , Volumen Espiratorio Forzado , Humanos , Masculino , Vehículos a Motor , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/fisiopatología , Trastornos Respiratorios/inducido químicamente , Trastornos Respiratorios/fisiopatología , Pruebas de Función Respiratoria , Xinafoato de Salmeterol , Resultado del Tratamiento , Estados Unidos
13.
Chron Respir Dis ; 9(2): 93-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22399574

RESUMEN

The Centers for Medicare and Medicaid Services has identified early rehospitalization of patients with chronic obstructive pulmonary disease (COPD) exacerbations as a performance measure for hospital care. We retrospectively reviewed patients with COPD who were admitted to University Medical Center, Lubbock, Texas, USA, between October 2010 and March 2011. There were 81 COPD patients with 103 hospitalizations. The mean age was 73.9 years. Pulmonary function tests using the Global initiative for chronic Obstructive Lung Disease criteria had been done in 36 patients (44.4%) and revealed 1 mild (2.8%), 7 moderate (19.4%), 20 severe (55.6%), and 8 very severe (22.2%) cases. Only 38.4% of the patients had prior influenza vaccine. Most patients were treated with antibiotics (81.8%) and corticosteroids (87.9%). The mean length of stay was 4.9 days, and 4 patients died. Most of the patients were discharged home (63.6%) with a median follow-up interval of 14 days. Thirty-two percent did not have long-acting bronchodilators and/or inhaled corticosteroids prescribed on discharge. There were 14 early rehospitalizations within 30 days. Logistic regression analysis indicated that a history of coronary artery disease (odds ratio (OR) 6.4, 95% confidence interval (CI) 1.1-37.4) and unilateral pulmonary infiltrates (OR 12.8, 95% CI 1.9-86.4) significantly increased the early rehospitalization rates. Acute exacerbations of COPD in patients with a history of ischemic heart disease or unilateral pulmonary infiltrates are at increased risk for early readmission. These risk factors should be identified during hospitalization; early follow-up or other interventions may reduce readmissions. Influenza vaccine, maintenance bronchodilators and/or inhaled corticosteroids, and pulmonary function tests were underused, and these standards of care should be provided to improve care.


Asunto(s)
Enfermedad de la Arteria Coronaria/complicaciones , Readmisión del Paciente/estadística & datos numéricos , Neumonía/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Corticoesteroides , Anciano , Anciano de 80 o más Años , Broncodilatadores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mejoramiento de la Calidad , Indicadores de Calidad de la Atención de Salud/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Texas
14.
Phys Rev Lett ; 107(14): 144801, 2011 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-22107200

RESUMEN

Measurements of the spatial and temporal coherence of single, femtosecond x-ray pulses generated by the first hard x-ray free-electron laser, the Linac Coherent Light Source, are presented. Single-shot measurements were performed at 780 eV x-ray photon energy using apertures containing double pinholes in "diffract-and-destroy" mode. We determined a coherence length of 17 µm in the vertical direction, which is approximately the size of the focused Linac Coherent Light Source beam in the same direction. The analysis of the diffraction patterns produced by the pinholes with the largest separation yields an estimate of the temporal coherence time of 0.55 fs. We find that the total degree of transverse coherence is 56% and that the x-ray pulses are adequately described by two transverse coherent modes in each direction. This leads us to the conclusion that 78% of the total power is contained in the dominant mode.

15.
J Chem Phys ; 134(2): 024504, 2011 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-21241117

RESUMEN

We present here the details of a phase retrieval technique that provides access to multidimensional modalities that are not currently available using existing interferometric techniques. The development of multidimensional optical spectroscopy has facilitated significant insights into electronic processes in physics, chemistry, and biology. The versatility and number of available techniques are, however, significantly limited by the requirement that the detection be interferometric. Many of these techniques are closely related to the vast range of multidimensional NMR spectroscopies, which revolutionized analytical chemistry more than 30 years ago. We focus here on the specific case of two-color multidimensional spectroscopy (analogous to heteronuclear NMR) and discuss the details of an iterative algorithm that recovers the relative phase relationships required to perform the Fourier transformation and find the unique solution for the 2D spectrum. A detailed guide is provided that describes the practical implementation of such algorithms. The effectiveness and accuracy of the phase retrieval process are assessed for simulated one- and two-color experiments. It is also compared with one-color experimental data for which the target phase information has been obtained independently by interferometry. In all the cases, the present algorithm yields results that compare well with the solutions obtained by other means. There are, however, some limitations and potential pitfalls that are identified and discussed. We conclude with a discussion of the potential applications and further advances that may be possible by adopting iterative phase retrieval algorithms of the type discussed here.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Algoritmos
16.
J Chem Phys ; 135(4): 044510, 2011 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-21806141

RESUMEN

We demonstrate three-dimensional (3D) electronic spectroscopy of excitons in a double quantum well system using a three-dimensional phase retrieval algorithm to obtain the phase information that is lost in the measurement of intensities. By extending the analysis of two-dimensional spectroscopy to three dimensions, contributions from different quantum mechanical pathways can be further separated allowing greater insight into the mechanisms responsible for the observed peaks. By examining different slices of the complete three-dimensional spectrum, not only can the relative amplitudes be determined, but the peak shapes can also be analysed to reveal further details of the interactions with the environment and inhomogeneous broadening. We apply this technique to study the coupling between two coupled quantum wells, 5.7 nm and 8 nm wide, separated by a 4 nm barrier. Coupling between the heavy-hole excitons of each well results in a circular cross-peak indicating no correlation of the inhomogeneous broadening. An additional cross-peak is isolated in the 3D spectrum which is elongated in the diagonal direction indicating correlated inhomogeneous broadening. This is attributed to coupling of the excitons involving the two delocalised light-hole states and the electron state localised on the wide well. The attribution of this peak and the analysis of the peak shapes is supported by numerical simulations of the electron and hole wavefunctions and the three-dimensional spectrum based on a density matrix approach. An additional benefit of extending the phase retrieval algorithm from two to three dimensions is that it becomes substantially more reliable and less susceptible to noise as a result of the more extensive use of a priori information.

17.
Opt Express ; 18(11): 11746-53, 2010 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-20589035

RESUMEN

Tomographic coherent imaging requires the reconstruction of a series of two-dimensional projections of the object. We show that using the solution for the image of one projection as the starting point for the reconstruction of the next projection offers a reliable and rapid approach to the image reconstruction. The method is demonstrated on simulated and experimental data. This technique also simplifies reconstructions using data with curved incident wavefronts.


Asunto(s)
Algoritmos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Refractometría/métodos , Tomografía de Coherencia Óptica/métodos
18.
Opt Express ; 18(3): 1981-93, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20174028

RESUMEN

We demonstrate use of a complex constraint based on the interaction of x-rays with matter for reconstructing images from coherent X-ray diffraction. We show the complementary information provided by the phase and magnitude of the reconstructed wavefield greatly improves the quality of the resulting estimate of the transmission function of an object without the need for a priori information about the object composition.

19.
QJM ; 113(2): 100-107, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31503318

RESUMEN

BACKGROUND: Proton pump inhibitors (PPI) and histamine-2 receptor antagonists (H2RA) have been widely used for multiple purposes. Recent studies have suggested an association between these medications and the risk of pancreatic cancer. However, the results have been inconclusive. AIM: We, therefore, conducted a study to assess the risk of developing pancreatic cancer in patients who used PPI and H2RA. DESIGN: A systematic review and meta-analysis. METHODS: A literature search was performed using MEDLINE and EMBASE databases from inception through February 2019. Studies that reported risk ratio comparing the risk of pancreatic cancer in patients who received PPI or H2RA versus those who did not receive treatments were included. Pooled risk ratios (RR) and 95% confidence intervals (CI) were calculated using a random-effect generic inverse variance method. Sensitivity analysis, excluding one study at a time, was performed. RESULTS: After screening abstracts from the searching methods, seven studies (six case-control studies and one cohort study) were included in the analysis with total 546 199 participants. Compared to patients who did not take medications, the pooled RR of developing pancreatic cancer in patients receiving PPI and H2RA were 1.73 (95% CI: 1.16-2.57) and 1.26 (95% CI: 1.02-1.57), respectively. However, the sensitivity analysis of PPI changed the pooled RR to 1.87 (95% CI: 1.00-3.51) after a study was dropped out. Likewise, H2RA sensitivity analysis also resulted in non-significant pooled RR. CONCLUSIONS: This meta-analysis did not find the strong evidence for the associations between the use of PPI and H2RA and pancreatic cancer.


Asunto(s)
Antagonistas de los Receptores H2 de la Histamina/uso terapéutico , Neoplasias Pancreáticas/diagnóstico , Inhibidores de la Bomba de Protones/uso terapéutico , Humanos , Oportunidad Relativa , Neoplasias Pancreáticas/etiología , Medición de Riesgo , Factores de Riesgo
20.
Phys Rev Lett ; 103(24): 243902, 2009 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-20366201

RESUMEN

The measured spatial coherence characteristics of the illumination used in a diffractive imaging experiment are incorporated in an algorithm that reconstructs the complex transmission function of an object from experimental x-ray diffraction data using 1.4 keV x rays. Conventional coherent diffractive imaging, which assumes full spatial coherence, is a limiting case of our approach. Even in cases in which the deviation from full spatial coherence is small, we demonstrate a significant improvement in the quality of wave field reconstructions. Our formulation is applicable to x-ray and electron diffraction imaging techniques provided that the spatial coherence properties of the illumination are known or can be measured.

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