214 research outputs found

    Macroscopic stress and strain in a doubly periodic array of dislocation dipoles

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    It is known that in two-dimensional periodic arrays of dislocations the summation of the periodic image fields is conditionally convergent. This is due to the long-range character of the elastic fields of dislocations. As a result, the stress field obtained for a doubly periodic array of dislocation dipoles may contain a spurious constant stress that depends on the adopted summation scheme. In the present work, we provide, based on micromechanical considerations, a simple physical explanation of the origin of the conditional convergence of lattice sums of image interactions. In this context, the spurious stresses are found in a closed form for an arbitrary elastic anisotropy, and this is achieved without using the stress field of an individual dislocation. An alternative procedure is also developed where the macroscopic spurious stresses are determined using the solution of the Eshelby's inclusion problem

    Cavernous Hemangioma of the Rib: A Rare Diagnosis

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    Hemangioma of the rib is an uncommon benign vascular tumour. A case of rib hemangioma in a 29-year-old woman is presented. Chest roentgenogram and computed tomography revealed a mass along the inner surface of the 7th left rib with bone destruction. She underwent resection of the 7th rib. The pathologic diagnosis was cavernous hemangioma. Hemangiomas of the rib are rare tumours but should be kept in mind in the differential diagnosis of rib tumours

    Constipation-Predominant Irritable Bowel Syndrome Associated to Hyperprolactinemia

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    Abstract Irritable bowel syndrome (IBS) is considered to be a physical disorder that mainly affects the bowel and is clinically characterized by lower abdominal pain or discomfort, diarrhea, constipation (or alternating diarrhea/constipation), gas, bloating, and nausea. According to recent studies, it appears that there is an association with increased prolactin levels in patients suffering from IBS. We report a rare case of regression of IBS symptoms (constipation type) in a 16-year-old female adolescent after receiving cabergoline for treating hyperprolactinemia due to pituitary macroadenoma. Our hypothesis is that increased prolactin levels, for instance due to a pituitary adenoma, may suppress prolactin-releasing peptide release and lead to a reverse feedback interaction, consequently resulting in oversecretion of cholecystokinin, inducing the development of IBS

    Acute lower limb compartment syndrome after Cesarean section: a case report

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    Abstract: Introduction Acute compartment syndrome of the lower limb is a rare but severe intra- and post-partum complication. Prompt diagnosis is essential to avoid permanent functional restriction or even the loss of the affected limb. Clinical signs and symptoms might be nonspecific, especially in the early stages; therefore, knowledge of predisposing risk factors can be helpful. Case presentation We present the case of a 32-year-old Caucasian woman with acute post-partum compartment syndrome. Conclusion: Acute compartment syndrome is an important differential diagnosis for the sudden onset of intra- or post-partum lower-limb pain. Predisposing factors for the manifestation of acute compartment syndrome in an obstetric environment are augmented intra-partum blood loss, prolonged hypotensive episodes and the use of oxytocin to support or induce labor because of its vasoconstrictive properties. Treatment is prompt surgical decompression by performing fasciotomy in any affected muscular compartments

    Compliance with evidence-based clinical guidelines in the management of acute biliary pancreatitis: the MANCTRA-1 study protocol

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    Despite existing evidence-based practice guidelines for the management of biliary acute pancreatitis (AP), the clinical compliance with recommendations is overall poor. Studies in this field have identified significant discrepancies between evidence-based recommendations and daily clinical practice. The most commonly reported gaps between clinical practice and AP guidelines include the indications for CT scan, need and timing of artificial nutritional support, indications for antibiotics, and surgical/endoscopic management of biliary AP. The MANCTRA-1 (coMpliAnce with evideNce-based cliniCal guidelines in the managemenT of acute biliaRy pancreAtitis) study is aiming to identify the areas for quality improvement that will require new implementation strategies. The study primary objective is to evaluate which items of the current AP guidelines are commonly disregarded and if they correlate with negative clinical outcomes according to the different clinical presentations of the disease. We attempt to summarize the main areas of sub-optimal care due to the lack of compliance with current guidelines to provide the basis for introducing a number of bundles in AP patients' management to be implemented during the next years. The MANCTRA-1 study is an international multicenter, retrospective cohort study with the purpose to assess the outcomes of patients admitted to hospital with a diagnosis of biliary AP and the compliance of surgeons worldwide to the most up-to-dated international guidelines on biliary AP. ClinicalTrials.Gov ID Number: NCT04747990, Date: February 23, 2021. Protocol Version V2.2

    Preoperative diagnosis of obscure gastrointestinal bleeding due to a GIST of the jejunum: a case report

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    Gastrointestinal stromal tumours (GISTs) are rare mesenchymal neoplasms affecting the digestive tract or nearby structures within the abdomen. We present a case of a 66-year-old female patient who presented with obscure anemia due to gastrointestinal bleeding and underwent exploratory laparotomy during which a large GIST of the small intestine was discovered. Examining the preoperative results of video capsule endoscopy, computed tomography, and angiography and comparing them with the operative findings we discuss which of these investigations plays the most important role in the detection and localization of GIST. A sort review of the literature is also conducted on these rare mesenchymal tumours

    Constipation-Predominant Irritable Bowel Syndrome Associated to Hyperprolactinemia

    Get PDF
    Irritable bowel syndrome (IBS) is considered to be a physical disorder that mainly affects the bowel and is clinically characterized by lower abdominal pain or discomfort, diarrhea, constipation (or alternating diarrhea/constipation), gas, bloating, and nausea. According to recent studies, it appears that there is an association with increased prolactin levels in patients suffering from IBS. We report a rare case of regression of IBS symptoms (constipation type) in a 16-year-old female adolescent after receiving cabergoline for treating hyperprolactinemia due to pituitary macroadenoma. Our hypothesis is that increased prolactin levels, for instance due to a pituitary adenoma, may suppress prolactin-releasing peptide release and lead to a reverse feedback interaction, consequently resulting in oversecretion of cholecystokinin, inducing the development of IBS
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