753 research outputs found

    Spontaneous gastrosplenic fistula in primary gastric lymphoma: case report and review of literature

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    A Cyproheptadine-Reversible Defect in ACTH Control Persisting after Removal of the Pituitary Tumor in Cushing\u27s Disease

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    Abstract We studied two phases of cortisol feedback suppression of ACTH in nine patients who had had adrenalectomy for Cushing\u27s disease. Four had been treated by adrenalectomy alone and presumably had ACTH-secreting pituitary tumors. Five others were studied two or more years after transsphenoidal removal of an ACTH-secreting microadenoma. In both groups, cortisol-ACTH feedback during the first 30 minutes of cortisol infusion was abnormal; plasma ACTH fell only 2.7Β±2.6 per cent (mean Β±S.E.), as compared with 28.0Β±10.1 per cent in five hypoadrenal controls (P\u3c0.01). The fall in ACTH during the second phase of cortisol infusion was similar in the patients and the controls. Cyproheptadine corrected the feedback abnormality occurring during the first phase in both groups of patients with Cushing\u27s disease; ACTH fell by 24.4Β±4.8 per cent (P\u3c0.005). Persistence of a cortisol-ACTH feedback abnormality after removal of the pituitary tumor in Cushing\u27s disease, as well as the correction by cyproheptadine, suggests that higher centers have a role in the pathophysiology of Cushing\u27s disease. (N Engl J Med. 1981; 305:1244–8.

    Deltaron Dibaryon Structure in Chiral SU(3) Quark Model

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    We discuss the structure of Deltaron dibaryon in the chiral SU(3) quark model. The energy of Deltaron is obtained by considering the coupling of the ΔΔ\Delta\Delta and CCCC (hidden color) channels. The effects of various parameters on the Deltaron mass are also studied. It is shown that the mass of Deltaron is lower than the mass of ΔΔ\Delta\Delta but higher than the mass of Ξ”NΟ€\Delta N \pi.Comment: 15 pages, Late

    Fast computation of Bernoulli, Tangent and Secant numbers

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    We consider the computation of Bernoulli, Tangent (zag), and Secant (zig or Euler) numbers. In particular, we give asymptotically fast algorithms for computing the first n such numbers in O(n^2.(log n)^(2+o(1))) bit-operations. We also give very short in-place algorithms for computing the first n Tangent or Secant numbers in O(n^2) integer operations. These algorithms are extremely simple, and fast for moderate values of n. They are faster and use less space than the algorithms of Atkinson (for Tangent and Secant numbers) and Akiyama and Tanigawa (for Bernoulli numbers).Comment: 16 pages. To appear in Computational and Analytical Mathematics (associated with the May 2011 workshop in honour of Jonathan Borwein's 60th birthday). For further information, see http://maths.anu.edu.au/~brent/pub/pub242.htm

    Evidence for a persistent, major excess in all cause admissions to hospital in children with type-1 diabetes: results from a large Welsh national matched community cohort study

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    OBJECTIVES: To estimate the excess in admissions associated with type1 diabetes in childhood. DESIGN: Matched-cohort study using anonymously linked hospital admission data. SETTING: Brecon Group Register of new cases of childhood diabetes in Wales linked to hospital admissions data within the Secure Anonymised Information Linkage Databank. POPULATION: 1577 Welsh children (aged between 0 and 15β€…years) from the Brecon Group Register with newly-diagnosed type-1 diabetes between 1999–2009 and 7800 population controls matched on age, sex, county, and deprivation, randomly selected from the local population. MAIN OUTCOME MEASURES: Difference in all-cause hospital admission rates, 30-days post-diagnosis until 31 May 2012, between participants and controls. RESULTS: Children with type-1 diabetes were followed up for a total of 12β€…102 person years and were at 480% (incidence rate ratios, IRR 5.789, (95% CI 5.34 to 6.723), p<0.0001) increased risk of hospital admission in comparison to matched controls. The highest absolute excess of admission was in the age group of 0–5β€…years, with a 15.4% (IRR 0.846, (95% CI 0.744 to 0.965), p=0.0061) reduction in hospital admissions for every 5-year increase in age at diagnosis. A trend of increasing admission rates in lower socioeconomic status groups was also observed, but there was no evidence of a differential rate of admissions between men and women when adjusted for background risk. Those receiving outpatient care at large centres had a 16.1% (IRR 0.839, (95% CI 0.709 to 0.990), p=0.0189) reduction in hospital admissions compared with those treated at small centres. CONCLUSIONS: There is a large excess of hospital admissions in paediatric patients with type-1 diabetes. Rates are highest in the youngest children with low socioeconomic status. Factors influencing higher admission rates in smaller centres (eg, β€œout of hours resources”) need to be explored with the aim of targeting modifiable influences on admission rates

    The nature of transition circumstellar disks. I. The ophiuchus molecular cloud

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    We have obtained millimeter-wavelength photometry, high-resolution optical spectroscopy, and adaptive optics near-infrared imaging for a sample of 26 Spitzer-selected transition circumstellar disks. All of our targets are located in the Ophiuchus molecular cloud (d ∼ 125pc) and have spectral energy distributions (SEDs) suggesting the presence of inner opacity holes. We use these ground-based data to estimate the disk mass, multiplicity, and accretion rate for each object in our sample in order to investigate the mechanisms potentially responsible for their inner holes. We find that transition disks are a heterogeneous group of objects, with disk masses ranging from JUP and accretion rates ranging from JUP) and negligible accretion (<10-11 M βŠ™yr-1), and are thus consistent with photoevaporating (or photoevaporated) disks. Four of these nine non-accreting objects have fractional disk luminosities <10-3 and could already be in a debris disk stage. Seventeen of our transition disks are accreting. Thirteen of these accreting objects are consistent with grain growth. The remaining four accreting objects have SEDs suggesting the presence of sharp inner holes, and thus are excellent candidates for harboring giant planets.Facultad de Ciencias AstronΓ³micas y GeofΓ­sica

    Transient Magnetic and Doppler Features Related to the White-light Flares in NOAA 10486

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    Rapidly moving transient features have been detected in magnetic and Doppler images of super-active region NOAA 10486 during the X17/4B flare of 28 October 2003 and the X10/2B flare of 29 October 2003. Both these flares were extremely energetic white-light events. The transient features appeared during impulsive phases of the flares and moved with speeds ranging from 30 to 50 km sβˆ’1^{-1}. These features were located near the previously reported compact acoustic \cite{Donea05} and seismic sources \cite{Zharkova07}. We examine the origin of these features and their relationship with various aspects of the flares, {\it viz.}, hard X-ray emission sources and flare kernels observed at different layers - (i) photosphere (white-light continuum), (ii) chromosphere (HΞ±\alpha 6563\AA), (iii) temperature minimum region (UV 1600\AA), and (iv) transition region (UV 284\AA).Comment: 26 pages, 13 figures, 2 tables, accepted for publication in Solar Physic

    Transgenic and Knockout Mice Models to Reveal the Functions of Tumor Suppressor Genes

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    Cancer is caused by multiple genetic alterations leading to uncontrolled cell proliferation through multiple pathways. Malignant cells arise from a variety of genetic factors, such as mutations in tumor suppressor genes (TSGs) that are involved in regulating the cell cycle, apoptosis, or cell differentiation, or maintenance of genomic integrity. Tumor suppressor mouse models are the most frequently used animal models in cancer research. The anti-tumorigenic functions of TSGs, and their role in development and differentiation, and inhibition of oncogenes are discussed. In this review, we summarize some of the important transgenic and knockout mouse models for TSGs, including Rb, p53, Ink4a/Arf, Brca1/2, and their related genes

    Dynamics of Coronal Bright Points as seen by Sun Watcher using Active Pixel System detector and Image Processing (SWAP), Atmospheric Imaging Assembly AIA), and Helioseismic and Magnetic Imager (HMI)

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    The \textit{Sun Watcher using Active Pixel system detector and Image Processing}(SWAP) on board the \textit{PRoject for OnBoard Autonomy\todash 2} (PROBA\todash 2) spacecraft provides images of the solar corona in EUV channel centered at 174 \AA. These data, together with \textit{Atmospheric Imaging Assembly} (AIA) and the \textit{Helioseismic and Magnetic Imager} (HMI) on board \textit{Solar Dynamics Observatory} (SDO), are used to study the dynamics of coronal bright points. The evolution of the magnetic polarities and associated changes in morphology are studied using magnetograms and multi-wavelength imaging. The morphology of the bright points seen in low-resolution SWAP images and high-resolution AIA images show different structures, whereas the intensity variations with time show similar trends in both SWAP 174 and AIA 171 channels. We observe that bright points are seen in EUV channels corresponding to a magnetic-flux of the order of 101810^{18} Mx. We find that there exists a good correlation between total emission from the bright point in several UV\todash EUV channels and total unsigned photospheric magnetic flux above certain thresholds. The bright points also show periodic brightenings and we have attempted to find the oscillation periods in bright points and their connection to magnetic flux changes. The observed periods are generally long (10\todash 25 minutes) and there is an indication that the intensity oscillations may be generated by repeated magnetic reconnection
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