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Seymour Philps 《BMJ (Clinical research ed.)》1941,2(4212):459-460
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The primary radiologic evidence of intra-abdominal hernia is disturbance of normal small intestine arrangement. Loops of intestine are crowded together as if in a bag, giving the appearance of clumping or sacculation. Dilatation and loss of mobility may occur with varying degrees of stasis. Displacement of viscera or pressure deformity may be observed.Studies of the small bowel are necessary to demonstrate these conditions and must be made with the patient in the erect as well as the horizontal position. Repeated studies may be required, and the best time to make them is during an acute attack, as the hernia may be temporarily reduced during a remission.The clinical symptoms are sufficiently characteristic to suggest the diagnosis in most cases. The usual history is of repeated attacks of abdominal pain or discomfort, usually accompanied by distention, varying in periodicity and intensity, with or without nausea or vomiting, and not accompanied by laboratory data or clinical signs indicative of inflammatory disease.Similar or identical clinical and roentgenologic evidence may be produced by torsion of the small bowel or by peritoneal adhesions.The hernia or torsion may reduce spontaneously before or at the time of operation. Therefore, a careful search for abnormal fossae, mesenteric defects or adhesive bands is necessary if herniation or torsion is not found. 相似文献
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The Drosophila orphan nuclear receptor DHR38 mediates an atypical ecdysteroid signaling pathway 总被引:1,自引:0,他引:1
Baker KD Shewchuk LM Kozlova T Makishima M Hassell A Wisely B Caravella JA Lambert MH Reinking JL Krause H Thummel CS Willson TM Mangelsdorf DJ 《Cell》2003,113(6):731-742
Ecdysteroid pulses trigger the major developmental transitions during the Drosophila life cycle. These hormonal responses are thought to be mediated by the ecdysteroid receptor (EcR) and its heterodimeric partner Ultraspiracle (USP). We provide evidence for a second ecdysteroid signaling pathway mediated by DHR38, the Drosophila ortholog of the mammalian NGFI-B subfamily of orphan nuclear receptors. DHR38 also heterodimerizes with USP, and this complex responds to a distinct class of ecdysteroids in a manner that is independent of EcR. This response is unusual in that it does not involve direct binding of ecdysteroids to either DHR38 or USP. X-ray crystallographic analysis of DHR38 reveals the absence of both a classic ligand binding pocket and coactivator binding site, features that seem to be common to all NGFI-B subfamily members. Taken together, these data reveal the existence of a separate structural class of nuclear receptors that is conserved from fly to humans. 相似文献
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Thermal processing of amorphous solid dispersions continues to gain interest in the pharmaceutical industry, as evident by several recently approved commercial products. Still, a number of pharmaceutical polymer carriers exhibit thermal or viscoelastic limitations in thermal processing, especially at smaller scales. Additionally, active pharmaceutical ingredients with high melting points and/or that are thermally labile present their own specific challenges. This review will outline a number of formulation and process-driven strategies to enable thermal processing of challenging compositions. These include the use of traditional plasticizers and surfactants, temporary plasticizers utilizing sub- or supercritical carbon dioxide, designer polymers tailored for hot-melt extrusion processing, and KinetiSol® Dispersing technology. Recent case studies of each strategy will be described along with potential benefits and limitations. 相似文献
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