301 research outputs found

    Polar foliations and isoparametric maps

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    A singular Riemannian foliation FF on a complete Riemannian manifold MM is called a polar foliation if, for each regular point pp, there is an immersed submanifold Σ\Sigma, called section, that passes through pp and that meets all the leaves and always perpendicularly. A typical example of a polar foliation is the partition of MM into the orbits of a polar action, i.e., an isometric action with sections. In this work we prove that the leaves of FF coincide with the level sets of a smooth map H:MΣH: M\to \Sigma if MM is simply connected. In particular, we have that the orbits of a polar action on a simply connected space are level sets of an isoparametric map. This result extends previous results due to the author and Gorodski, Heintze, Liu and Olmos, Carter and West, and Terng.Comment: 9 pages; The final publication is available at springerlink.com http://www.springerlink.com/content/c72g4q5350g513n1

    Peritoneal and hepatic hydatid disease causing major bile duct destruction

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    Echinococcosis is endemic in Mediterranean regions and is found primarily in the liver. Biliary fistula is a common complication, but major biliary duct involvement is very rare, and occurs in 0.47% of patients with hepatic hydatid disease. Cyst rupture causing secondary peritoneal hydatidosis is a rare but serious complication. We report the case of a 27-year-old man with multiple peritoneal and hepatic hydatid cysts. The patient came to our attention with cholestatic jaundice. Imaging exams showed numerous peritoneal cysts and massive hydatid disease of the liver, which involved the hepatic confluence, with destruction of the right hepatic duct and fistula formation to the left hepatic duct. The patient was treated with pre-operative albendazole therapy and radical surgery, which consisted of resection of all peritoneal cysts and extended right hepatectomy with biliary reconstruction. No recurrence was seen on CT investigations on the 12th month following surgery. Radical surgical approach remains the treatment of choice

    Rupture of splenic angiosarcoma: a rare cause of spontaneous haemoperitoneum

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    Primary splenic angiosarcoma, a very rare mesenchymal tumour of endothelial cell origin, comprises 2.6% of all cases of angiosarcoma and 10% of all primitive splenic tumours. Clinical presentation is usually unspecific, with abdominal pain and anaemia. Rupture is a rare complication and should prompt emergency splenectomy. Prognosis is usually poor because of liver, lung or bone metastases. We describe the case of an 80-year-old woman admitted to the emergency room with syncope, hypotension and vomiting. She stabilised after fluid resuscitation. Investigations showed anaemia, a large, heterogeneous spleen and free fluid in the abdominal cavity. She underwent emergency splenectomy. Pathology revealed primary splenic angiosarcoma. The postoperative period was complicated by respiratory failure but the patient made an otherwise uneventful course and was discharged 2 weeks after surgery. Six months after the operation she remains free of disease with no adjuvant treatment

    Locally advanced adenocarcinoma of the rectum presenting with necrotising fasciitis of the perineum: successful management with early aggressive surgery and multimodal therapy

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    Colorectal cancer is a common malignant neoplasm and its treatment usually involves surgery associated, in some cases, depending on the staging, with chemoradiotherapy. Necrotising fasciitis of the perineum is a highly lethal infection of the perineum, perirectal tissues and genitals, requiring emergency surgical debridement, broad-spectrum antibiotics and control of sepsis. We present the case of a 59-year-old man with necrotising fasciitis of the perineum as the first clinical manifestation of locally advanced adenocarcinoma of the rectum, in which successful management consisted of early and aggressive surgical debridement, followed by multimodal therapy with curative intent. 2 years and 6 months after surgery the patient is well, with no evidence of local or systemic relapse.info:eu-repo/semantics/publishedVersio

    Oxaliplatin toxicity presenting as a liver nodule - case report

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    BACKGROUND: Oxaliplatin based chemotherapy is often used as adjuvant therapy in colon and rectal cancer. A reported side effect is Sinusoidal Obstruction Syndrome which is characterized by a spectrum of pathologic changes, from sinusoidal dilation, peri-sinusoidal haemorrhage, peliosis and nodular regenerative hyperplasia. Very rarely it can cause the development of liver nodules mimicking liver metastases. Herein, we report a case of Sinusoidal Obstruction Syndrome causing a liver nodule suspicious of liver metastasis on imaging. This is the third reported case of this complication of oxaliplatin toxicity, in which resection was performed and pathological diagnosis confirmed. CASE PRESENTATION: We report the case of a 59 year old man with stage III colon cancer who underwent sigmoidectomy followed by adjuvant chemotherapy with oxaliplatin. One year after surgery a liver nodule was detected and the patient underwent right hepatectomy. Pathology showed no liver nodule and diagnosed sinusoidal obstruction syndrome. CONCLUSION: We describe the third reported case of a liver lesion mimicking a liver metastasis after oxaliplatin-based chemotherapy for colon cancer. We suggest that in patients heavily treated with oxaliplatin with de novo liver nodules, this differential diagnosis should be considered. In particular, in this population of patients an intense imagiologic evaluation and even a preoperative biopsy should be pursued to confirm the diagnosis of malignancy and avoid overtreatment.info:eu-repo/semantics/publishedVersio

    Composição bromatológica de silagens de híbridos de sorgo cultivados em diferentes densidades de plantas.

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    Avaliou-se a composição bromatológica das silagens de dois híbridos de sorgo, AG-2005 (duplo propósito) e VOLUMAX (forrageiro), cultivados nos espaçamentos de 0,50; 0,75 e 1,00 m, resultando nas densidades de 140.000; 186.666 e 280.000 plantas por ha, respectivamente. A silagem do híbrido AG-2005 apresentou matéria seca (MS) superior no espaçamento de 1,00 m e foi mais elevada ao da silagem de VOLUMAX em todos os espaçamentos. A proteína bruta (PB) elevou-se com a redução dos espaçamentos (6,6; 6,8 e 8%, respectivamente), com maior valor médio no AG-2005 (7,7 vs 6,5%). A fibra em detergente neutro (FDN) foi menor no AG-2005 (59,25 vs 62,3%) e no espaçamento 0,75 m. Para fibra em detergente ácido (FDA) ocorreu diferença entre os dois híbridos no espaçamento 0,5 m, sendo de 33,5 e 39,3 %, respectivamente, para o AG-2005 e VOLUMAX. O EE apresentou diferença significativa (P < 0,05) entre os dois híbridos no espaçamento 0,75 m, sendo maior no AG-2005 (2,05 vs 1,61%). Conclui-se que o híbrido AG-2005 é mais recomendado para ensilagem, pois a sua silagem apresenta características qualitativas melhores que do VOLUMAX. O espaçamento de 0,5 m é o mais indicado no plantio dos híbridos, pois melhora a composição química das silagens. Chemical composition of silage sorghum hybrids grown at different densities. AbstractT - The objective of the experiment was to evaluate the nutritive value of silages from two sorghum hybrids, AG-2005 (double purpose) and VOLUMAX (forage) cultivated with different row spacings (0.50 m; 0.75 m and 1.00 m), resulting in 140,000; 186,666 e 280,000 plants per ha, respectively. Dry matter content of AG-2005 silage was higher for 1 m row spacing, and was higher than for VOLUMAX silage in all row spacings. Crude protein increased as the row spacing was reduced (6.6; 6.8 and 8%, respectively), with higher average value for AG-2005 (7.7 vs 6.5%). Neutral detergent fiber was lower for AG-2005 (59.25 vs 62.3%) and for .75 m spacing. Acid detergent fiber differed between hybrids in .5 m row spacing, being 33.5 and 39.3%, respectively, for AG-2005 and VOLUMAX. Ether extract was significantly different between hybrids in .5 m row spacing, being higher for AG-2005 (2.05 vs 1.61%). The use of AG-2005 is recommended for silage production due to its better qualitative characteristics than the VOLUMAX. The .5 m row spacing is recommended for both hybrids, since it improves the chemical composition of the silages

    Valor nutritivo de silagens de híbridos de sorgo (Sorghum bicolor, l. Moench) em função de diferentes densidades de plantio.

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    Avaliou-se o valor nutritivo de silagens de dois híbridos de sorgo (AG 2005 e VOLUMAX), sob diferentes densidades de plantio (1,00m; 0,75m e 0,50m). Foram determinados os teores de proteína bruta e frações fibrosas. O delineamento experimental utilizado foi de blocos ao acaso com quatro repetições, sendo os tratamentos arranjados em esquema fatorial 3x2 (espaçamento x híbrido). As médias foram comparadas pelo teste de Tukey (P<0,05). Frações fibrosas da matéria seca não variaram com o aumento da densidade. O adensamento do espaçamento de plantio afetou o teor de proteína bruta das silagens dos híbridos AG 2005 e VOLUMAX de forma positiva, tendo apresentado média superior no espaçamento menor. Conclui-se que os híbridos estudados podem ser cultivados adensados, pois eleva o valor nutritivo. NUTRITIVE VALUE OF SILAGES FROM SORGHUM HYBRIDS (SORGHUM BICOLOR, L. MOENCH) WITH DIFFERENT PLANT DENSITY. Abstract: Nutritional values of two silages from the sorghum hybrids (AG 2005 and VOLUMAX) with different row spacing (1,00 m; 0,75 m and 0,50 m) were evaluated. Crude protein and fibrous fractions in dry matter were determined in silage. A randomized block design with four replicates was used. The treatments consisted in a factorial arrangement 3x2 (row spacing x hybrids). The means were compared by Tukey test (P<0.05). No effects of row spacing of the plant on fibrous fractions were found. Crude protein with silages increasing with narrow spacing. Concluding, these hybrids can be produced in high density, therefore your nutritive values are elevated
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