554 research outputs found

    Preschool children's use of perceptual-motor knowledge and hierarchical representational skills for tool making

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    Although other animals can make simple tools, the expanded and complex material culture of humans is unprecedented in the animal kingdom. Tool making is a slow and late-developing ability in humans, and preschool children find making tools to solve problems very challenging. This difficulty in tool making might be related to the lack of familiarity with the tools and may be overcome by children's long term perceptual-motor knowledge. Thus, in this study, the effect of tool familiarity on tool making was investigated with a task in which 5-to-6-yearold children (n = 75) were asked to remove a small bucket from a vertical tube. The results show that children are better at tool making if the tool and its relation to the task are familiar to them (e.g., soda straw). Moreover, we also replicated the finding that hierarchical complexity and tool making were significantly related. Results are discussed in light of the ideomotor approach

    Correlation of Dynamic PET and Gene Array Data in Patients with Gastrointestinal Stromal Tumors

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    Introduction. The results obtained with dynamic PET (dPET) were compared to gene expression data obtained in patients with gastrointestinal stromal tumors (GIST). The primary aim was to assess the association of the dPET results and gene expression data. Material and Methods. dPET was performed following the injection of F-18-fluorodeoxyglucose (FDG) in 22 patients with GIST. All patients were examined prior to surgery for staging purpose. Compartment and noncompartment models were used for the quantitative evaluation of the dPET examinations. Gene array data were based on tumor specimen obtained by surgery after the PET examinations. Results. The data analysis revealed significant correlations for the dPET parameters and the expression of zinc finger genes (znf43, znf85, znf91, znf189). Furthermore, the transport of FDG (k1) was associated with VEGF-A. The cell cycle gene cyclin-dependent kinase inhibitor 1C was correlated with the maximum tracer uptake (SUVmax) in the tumors. Conclusions. The data demonstrate a dependency of the tracer kinetics on genes associated with prognosis in GIST. Furthermore, angiogenesis and cell proliferation have an impact on the tracer uptake

    The importance of radiological controls of anastomoses after upper gastrointestinal tract surgery - a retrospective cohort study

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    <p>Abstract</p> <p>Introduction</p> <p>This study was designed to analyze whether routine radiological controls of anastomoses in the upper gastrointestinal tract an early detection of anastomotic leaks.</p> <p>Patients and Methods</p> <p>135 patients who underwent upper gastrointestinal tract surgery were retrospectively analyzed. Patients in the first group (n = 55) underwent routine radiological control of the anastomoses. In the second group (n = 80) the radiological control was only performed in case of clinical symptoms or signs of anastomotic leaks.</p> <p>Results</p> <p>The incidence of anastomotic leaks in the patients seen by us was 5.2%, equivalent to 7 of 135 patients In Group 1 leaks were seen in 4 of 55 patients (7,2%) in group 2 leaks were seen in 3 of 80 (3,8%). The radiological control of the anastomoses with contrast swallow showed the leakage in two cases. Twice the results were false negative. The sensitivity of computed tomography was 100%.</p> <p>Discussion</p> <p>Routine radiological control of anastomoses with contrast swallow only has low sensitivity. This procedure should not be performed routinely any more.</p> <p>The radiological control should be used in cases with signs of anastomotic leakage or with postoperatively impaired gastrointestinal passage.</p

    Determination and analysis of plasma radiative properties for numerical simulations of laboratory radiative blast waves launched in xenon clusters

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    Radiative shock waves play a pivotal role in the transport energy into the stellar medium. This fact has led to many efforts to scale the astrophysical phenomena to accessible laboratory conditions and their study has been highlighted as an area requiring further experimental investigations. Low density material with high atomic mass is suitable to achieve radiative regime, and, therefore, low density xenon plasmas are commonly used for the medium in which the radiative shocks propagate. The knowledge of the plasma radiative properties is crucial for the correct understanding and for the hydrodynamic simulations of radiative shocks. In this work, we perform an analysis of the radiative properties of xenon plasmas in a range of matter densities and electron temperatures typically found in laboratory experiments of radiative shocks launched in xenon plasmas. Furthermore, for a particular experiment, our analysis is applied to make a diagnostics of the electron temperatures of the radiative shocks since they could not be experimentally measure

    The cientificWorldJOURNAL Clinical Study Correlation of Dynamic PET and Gene Array Data in Patients with Gastrointestinal Stromal Tumors

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    Introduction. The results obtained with dynamic PET (dPET) were compared to gene expression data obtained in patients with gastrointestinal stromal tumors (GIST). The primary aim was to assess the association of the dPET results and gene expression data. Material and Methods. dPET was performed following the injection of F-18-fluorodeoxyglucose (FDG) in 22 patients with GIST. All patients were examined prior to surgery for staging purpose. Compartment and noncompartment models were used for the quantitative evaluation of the dPET examinations. Gene array data were based on tumor specimen obtained by surgery after the PET examinations. Results. The data analysis revealed significant correlations for the dPET parameters and the expression of zinc finger genes (znf43, znf85, znf91, znf189). Furthermore, the transport of FDG (k1) was associated with VEGF-A. The cell cycle gene cyclin-dependent kinase inhibitor 1C was correlated with the maximum tracer uptake (SUVmax) in the tumors. Conclusions. The data demonstrate a dependency of the tracer kinetics on genes associated with prognosis in GIST. Furthermore, angiogenesis and cell proliferation have an impact on the tracer uptake

    Long-Term Relapse-Free Survival by Interdisciplinary Collaboration in a Patient with Metastatic Pancreatic Cancer (UICC IV)

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    Introduction: The prognostic outlook for patients suffering from pancreatic cancer is generally poor. Particularly in cases of advanced and metastatic disease, long-term relapse-free survival may be achieved only in a few cases. Case Report: A 45-year-old patient presented with metastatic pancreatic cancer. Liver metastases had been intra-operatively confirmed by histology. Prior to initiating treatment, a portacath was surgically implanted. Subsequently, the patient received a weekly dose of 1,000 mg/m2 gemcitabine combined with 2,000 mg/m2 high-dose 5-fluorouracil as a 24-hour infusion for palliative treatment. As the patient was suffering from a stenosis of the ductus hepaticus communis, an endoprosthesis was primarily implanted. After 18 applications of chemotherapy during which only low toxic side effects such as nausea, vomiting and alopecia (NCI-CTC grade 1) presented, a partial remission of the primary tumor was observed. In the course of chemotherapy treatment, the carbohydrate antigen 19-9 tumor marker value normalized. Thus, the interdisciplinary tumor board of the University of Erlangen decided to perform a laparoscopy to evaluate the status of liver metastases after palliative chemotherapy treatment. Subsequently, the primary tumor could be completely resected (pT2, pN0, pM0, L0, V0, G2, R0); liver metastases were not observed. Eight years after the initial diagnosis, the patient is relapse-free, professionally fully integrated and presents with an excellent performance status. Conclusion: Patients suffering from metastatic pancreatic cancer may benefit from treatment combinations with palliative intent. In singular cases, patients may even have a curative treatment option, provided a close interdisciplinary collaboration exists

    Cystic colon duplication causing intussusception in a 25-year-old man: report of a case and review of the literature

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    <p>Abstract</p> <p>Background</p> <p>Colonic intussusception is a rare congenital abnormality, mostly manifesting before the age of two with abdominal pain and acute intestinal obstruction with or without bleeding. In adults it may occur idiopathically or due to an intraluminal tumor mass.</p> <p>Case presentation</p> <p>A 25-year-old man presented with an acute abdomen and severe crampy abdominal pain. The clinical picture mimicked acute appendicitis. Transabdominal ultrasound examination revealed a 5 cm circular mass in the right upper abdomen. The ensuing computed tomography suggested an intussusception in the ascending colon. Intraoperatively, no full thickness invagination was detected. Due to a hard, intraluminal tumor a standard right hemicolectomy with ileotransversostomy was performed. The histopathological analysis revealed a cystic colon duplication leading to mucosal invagination and obstruction.</p> <p>Conclusions</p> <p>In adults, colon intussusception is a rare event causing approximately 1% of all acute intestinal obstructions. Unlike its preferentially nonsurgical management in children, a bowel intussusception in adults should be operated because an organic, often malignant lesion is present in most cases.</p
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