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1.
Sci Rep ; 13(1): 17589, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37845286

RESUMEN

The valorisation of waste or by-products in Portland clinker production is a promising alternative for developing sustainable cements. The complexity of the chemical reactions during clinkering demands an adequate dosing method that considers the effect of feedstock impurities to maximise the potential substitution of natural resources by waste or by-products, while guaranteeing the clinker reactivity requirements. This study proposes a raw meal proportioning methodology for optimising co-processing of natural feedstocks with alternative raw materials in clinker production, intending to reduce the content of natural raw materials needed, while promoting an optimal clinker reactivity. A thermodynamic modelling sequence was developed considering the variability of raw materials composition and heating temperatures. The model was then validated by comparing simulation outcomes with results reported in previous studies. An experimental case study was conducted for validation of the proposed method using a spent fluid catalytic cracking catalyst (SFCC), a by-product from the oil industry as an alternative alumina source during clinkering. The modelling simulations indicated that substitution of natural feedstocks by 15 wt% SFCC promotes the formation of reactive clinkers with more than 54% tricalcium silicate (C3S). Mixes with the potential to form the highest C3S were then produced, and heating microscopy fusibility testing was applied for evaluating the clinkers' stability. The main factors governing the reactivity and stability of the clinker phases were the melt phase content, alumina modulus, and formation of C3S and dicalcium silicate (C2S). The self-pulverisation of clinker during cooling was observed in selected mixes, and it is potentially associated with high viscosity and low Fe content in the melt phase. The proposed framework enables optimisation of the dosing of raw meals containing alternative alumina-rich feedstocks for clinker production and allows a deeper interpretation of limited sets of empirical data.

2.
ScientificWorldJournal ; 2016: 4949183, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27069982

RESUMEN

Styrene is an important monomer in the manufacture of thermoplastic. Most of it is produced by the catalytic dehydrogenation of ethylbenzene. In this process that depends on reversible reactions, the yield is usually limited by the establishment of thermodynamic equilibrium in the reactor. The styrene yield can be increased by using a hybrid process, with reaction and separation simultaneously. It is proposed using permselective composite membrane to remove hydrogen and thus suppress the reverse and secondary reactions. This paper describes the simulation of a dehydrogenation process carried out in a tubular fixed-bed reactor wrapped in a permselective composite membrane. A mathematical model was developed, incorporating the various mass transport mechanisms found in each of the membrane layers and in the catalytic fixed bed. The effects of the reactor feed conditions (temperature, steam-to-oil ratio, and the weight hourly space velocity), the fixed-bed geometry (length, diameter, and volume), and the membrane geometry (thickness of the layers) on the styrene yield were analyzed. These variables were used to determine experimental conditions that favour the production of styrene. The simulation showed that an increase of 40.98% in the styrene yield, compared to a conventional fixed-bed process, could be obtained by wrapping the reactor in a permselective composite membrane.

3.
Cancer Radiother ; 19(8): 762-74, 2015 Dec.
Artículo en Francés | MEDLINE | ID: mdl-26508321

RESUMEN

Malignant tumours of the eye are not common, barely representing 1 % of all cancers. This article aims to summarise, for each of the main eye malignant diseases, aspects of epidemiology, diagnostic methods and treatments, with a focus on radiation therapy techniques. The studied tumours are: eye metastasis, intraocular and ocular adnexal lymphomas, uveal melanomas, malignant tumours of the conjunctive, of the lids, and retinoblastomas. The last chapter outlines ocular complications of radiation therapy and their management.


Asunto(s)
Neoplasias del Ojo , Carcinoma/diagnóstico , Carcinoma/epidemiología , Carcinoma/radioterapia , Árboles de Decisión , Neoplasias del Ojo/diagnóstico , Neoplasias del Ojo/epidemiología , Neoplasias del Ojo/radioterapia , Neoplasias del Ojo/secundario , Neoplasias de los Párpados/diagnóstico , Neoplasias de los Párpados/epidemiología , Neoplasias de los Párpados/radioterapia , Humanos , Linfoma/diagnóstico , Linfoma/epidemiología , Linfoma/radioterapia , Melanoma/diagnóstico , Melanoma/epidemiología , Melanoma/radioterapia , Retinoblastoma/diagnóstico , Retinoblastoma/epidemiología , Retinoblastoma/radioterapia , Neoplasias de la Úvea/diagnóstico , Neoplasias de la Úvea/epidemiología , Neoplasias de la Úvea/radioterapia
4.
Plant Cell Environ ; 38(11): 2353-71, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25871738

RESUMEN

Transcriptomic and proteomic studies have improved our knowledge of guard cell function; however, metabolic changes in guard cells remain relatively poorly understood. Here we analysed metabolic changes in guard cell-enriched epidermal fragments from tobacco during light-induced stomatal opening. Increases in sucrose, glucose and fructose were observed during light-induced stomatal opening in the presence of sucrose in the medium while no changes in starch were observed, suggesting that the elevated fructose and glucose levels were a consequence of sucrose rather than starch breakdown. Conversely, reduction in sucrose was observed during light- plus potassium-induced stomatal opening. Concomitant with the decrease in sucrose, we observed an increase in the level as well as in the (13) C enrichment in metabolites of, or associated with, the tricarboxylic acid cycle following incubation of the guard cell-enriched preparations in (13) C-labelled bicarbonate. Collectively, the results obtained support the hypothesis that sucrose is catabolized within guard cells in order to provide carbon skeletons for organic acid production. Furthermore, they provide a qualitative demonstration that CO2 fixation occurs both via ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPcase). The combined data are discussed with respect to current models of guard cell metabolism and function.


Asunto(s)
Dióxido de Carbono/metabolismo , Nicotiana/metabolismo , Fosfoenolpiruvato Carboxilasa/metabolismo , Estomas de Plantas/fisiología , Ribulosa-Bifosfato Carboxilasa/metabolismo , Sacarosa/metabolismo , Cinética , Células Vegetales/metabolismo , Células Vegetales/fisiología , Estomas de Plantas/efectos de la radiación , Nicotiana/citología
5.
Cancer Treat Rev ; 40(10): 1119-28, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25451606

RESUMEN

BACKGROUND: Choroidal metastases (CM) are the most common malignant intraocular lesion observed in up to 4-12% of necropsy series of patients with solid cancer. The spectrum of presentations varies from prevalent CM in disseminated cancer to isolated CM. CM are responsible for visual deterioration. Depending on the primary cancer, estimated life expectancy, overall cancer presentation and ocular symptoms, the management of CM varies widely. We address the multidisciplinary management of CM and technical aspects of radiotherapy. MATERIAL AND METHODS: A systematic review of literature was performed from 1974 to 2014. RESULTS: Choroidal metastases occur preferentially in breast and lung carcinomas but are reported in all cancer types. The standard treatment remains external beam radiotherapy, applying 30Gy in 10 fractions or 40Gy in 20 fractions. The reported complete response and improved visual acuity rates are 80% and 57% to 89%, respectively. Some chemotherapy or new targeted therapy regimens yield promising CM response rates. DISCUSSION: Radiation therapy consistently shows rapid symptom alleviation, yield excellent local control and functional outcomes. However, there are only few reports on late toxicities after 6months given the unfavorable prognostic of CM patients. Selected patients may live more than two years, underlying the need to better assess mean and long term outcomes. Some authors have favored exclusive systemic strategies with omission of irradiation. The current literature suffers from the scarcity of prospective trials. Duration of tumor response following systemic therapy is rarely reported but appears less favorable as compared to radiotherapy. Systemic treatments may be proposed for pauci-symptomatic CM in a polymetastatic context while radiation therapy remains necessary in symptomatic CM either upfront or as an alternating treatment. Focalized radiation like brachytherapy and proton therapy may be proposed for isolated CM with long disease-free interval between primary and CM, as these techniques have the potential to yield better tumor and functional outcomes in patients with long life expectancy.


Asunto(s)
Neoplasias de la Coroides/diagnóstico , Neoplasias de la Coroides/radioterapia , Braquiterapia/métodos , Neoplasias de la Coroides/complicaciones , Neoplasias de la Coroides/epidemiología , Neoplasias de la Coroides/terapia , Terapia Combinada , Angiografía con Fluoresceína , Humanos , Imagen por Resonancia Magnética/métodos , Microscopía Acústica/métodos , Oftalmoscopía/métodos , Resultado del Tratamiento
6.
J Antimicrob Chemother ; 69(6): 1681-7, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24474430

RESUMEN

OBJECTIVES: There are controversies regarding the association of cefepime therapy with increased mortality among patients with infections caused by Gram-negative bacteria (GNB). We evaluated the effect of cefepime on the mortality of patients with GNB bloodstream infections (BSIs). METHODS: A prospective cohort study was conducted in adult patients with creatinine ≤1.5 mg/dL who received empirical therapy with cefepime for at least 48 h for BSIs caused by GNB. The outcome was hospital mortality. Potential clinical predictors, including a high-dose regimen (2 g every 8 h), were assessed. RESULTS: One hundred and thirteen patients were included. Most (78.8%) isolates had low cefepime MICs (≤0.25 mg/L). The overall hospital mortality was 35.4% [25.6% (10/39) and 40.5% (30/74) in patients receiving high-dose and usual-dose cefepime, respectively (P = 0.17)]. In a Cox regression model adjusted for cefepime MIC and propensity score, a high-dose regimen was independently associated with lower mortality rates [adjusted hazard ratio (aHR) 0.41; 95% CI 0.18-0.91; P = 0.029] while presentation with severe sepsis or septic shock was independently associated with higher mortality rates (aHR 4.10; 95% CI 1.78-9.40; P = 0.001). A trend to lower mortality rates was also found in the subgroup analysis of patients who had not switched antibiotic during therapy after adjustment for the latter variables. CONCLUSIONS: High-dose cefepime therapy was associated with lower mortality rates in patients with GNB BSIs, even for GNB with low cefepime MICs.


Asunto(s)
Antibacterianos/administración & dosificación , Bacteriemia/tratamiento farmacológico , Bacteriemia/mortalidad , Cefalosporinas/administración & dosificación , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/mortalidad , Adulto , Anciano , Bacteriemia/microbiología , Cefepima , Farmacorresistencia Bacteriana , Sustitución de Medicamentos , Femenino , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/microbiología , Mortalidad Hospitalaria , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Resultado del Tratamiento
7.
Cancer Radiother ; 18(1): 68-76, 2014 Jan.
Artículo en Francés | MEDLINE | ID: mdl-24387927

RESUMEN

Parotid pleomorphic adenoma is the most frequent tumor of salivary glands. The prognosis depends on the recurrences because they could lead to iatrogenic events (facial paralysis). Moreover the risk of malignant transformation increases with the number of local relapses. This article aims at reviewing histological and radiological criteria and the surgical techniques. To improve local control, adjuvant irradiation (in first intention or after recurrence) may be useful but is still controversial for benign tumors in young patients with a risk of radio-induced cancer. We listed studies in which adjuvant radiotherapy was used so as to define its place in the treatment strategy. Prognostic factors were found by some authors. Other studies have to be done before strong evidence-based recommendations are issued.


Asunto(s)
Adenoma Pleomórfico/radioterapia , Neoplasias de la Parótida/radioterapia , Adenoma Pleomórfico/diagnóstico , Adenoma Pleomórfico/epidemiología , Adenoma Pleomórfico/cirugía , Factores de Edad , Traumatismos del Nervio Facial/prevención & control , Humanos , Recurrencia Local de Neoplasia/prevención & control , Neoplasias Inducidas por Radiación/prevención & control , Tratamientos Conservadores del Órgano , Neoplasias de la Parótida/diagnóstico , Neoplasias de la Parótida/epidemiología , Neoplasias de la Parótida/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Pronóstico , Traumatismos por Radiación/prevención & control , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia Adyuvante
8.
Pesqui. vet. bras ; 29(8): 653-660, ago. 2009. ilus
Artículo en Inglés | LILACS | ID: lil-531769

RESUMEN

In the last few years, the use of laparoscopy in veterinary medicine has expanded and consequently so was the need for studies that establish the advantages, disadvantages and possible complications of each procedure. The purpose of the current study was to describe a laparoscopic splenectomy technique and the alterations due to this access, and compare it to the open procedure in dogs. A total of 15 healthy female mongrel dogs were used, with mean weight of 17.4±2.5kg. The animals were distributed into three groups: Group IA of open splenectomy (laparotomy) using double ligation of the vessels of the splenic hilum with poliglicolic acid, Group IB of open splenectomy (laparotomy) with bipolar electrocoagulation of the splenic hilum, and Group II of laparoscopic access with bipolar electrocoagulation of the splenic hilum. Operative time, blood loss, size of incisions, complications during and after surgery were evaluated. Other parameters included pain scores, white blood cell (WBC) counts and postoperative serum concentrations of alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine kinase (CK), C-reactive protein (CRP), glucose and cortisol. No differences were found in the evaluation of parameters between both open splenectomy techniques employed. Laparoscopic access presented significant differences (p<0,05) when compared with open surgery: Longer operative time, smaller abdominal access, decrease in blood loss, lower concentrations of CRP, higher levels of CK and ALP, and lower scores in the pain scale. Laparoscopic surgery showed fewer complications of the surgical wound. No significant differences were observed between groups in the postoperative temperature, WBC, ALT, cortisol and glucose concentrations. In conclusion, the laparoscopic technique is useful for splenectomy in dogs, being advantageous in terms of blood loss, surgical stress and surgical wounds. However, it expends more operative time and causes transitory...


Nos últimos anos, a utilização da laparoscopia em Medicina Veterinária vem expandindo e, conseqüentemente, a necessidade de pesquisas que determinem as vantagens, desvantagens e possíveis complicações de cada procedimento. Este estudo teve como objetivo descrever uma técnica de esplenectomia laparoscópica, assim como as alterações decorrentes deste acesso, e compará-la ao procedimento convencional em cães. Foram utilizadas 15 cadelas hígidas, sem raça definida, com peso médio de 17,4 ±2,5kg. Os animais foram distribuídos em três grupos: Grupo IA de acesso convencional (por laparotomia) utilizando ligadura com ácido poliglicólico no selamento vascular do hilo esplênico, Grupo IB de acesso convencional (por laparotomia) com eletrocoagulador bipolar do hilo esplênico, e Grupo II de acesso laparoscópico com eletrocoagulador bipolar para selamento vascular dos ramos esplênicos. Estes grupos foram avaliados em relação ao tempo cirúrgico, à perda de sangue, ao tamanho das incisões e às complicações durante e após a cirurgia. Também foram comparadas as avaliações da escala de dor e as alterações no leucograma e nas concentrações séricas da alanina aminotransferase (ALT), da fosfatase alcalina (FA), da creatina quinase (CK), da proteína C-reativa (CRP), da glicose e do cortisol no pós-operatório. Os acessos convencionais não diferiram entre si nos parâmetros avaliados. O acesso laparoscópico apresentou diferenças significativas (p<0,05) quando comparado ao convencional: maior tempo cirúrgico, menor acesso abdominal, diminuição na perda de sangue, menores concentrações de CRP, maiores níveis de CK e FA, além de pontuação menor na escala de dor. A cirurgia laparoscópica apresentou menor número de complicações das feridas cirúrgicas. A ALT, o cortisol, a glicemia, o leucograma e a temperatura retal pós-operatórias não diferiram significativamente entre os acessos convencional e laparoscópico. Conclui-se que a cirurgia laparoscópica é viável para...


Asunto(s)
Animales , Perros , Bazo/cirugía , Esplenectomía/métodos , Laparoscopía/métodos , Trastornos por Estrés Postraumático/cirugía
9.
Ann Pathol ; 19(6): 525-8, 1999 Dec.
Artículo en Francés | MEDLINE | ID: mdl-10617811

RESUMEN

A 72-year-old woman in good general health presented a massive intestinal and colonic ischemia with rapid post-operative death, due to mesenteric inflammatory veno-occlusive disease. Mesenteric inflammatory veno-occlusive disease, first described in 1994, is a vasculitis of unknown etiology limited to the mesenteric area, affecting exclusively veins and venules and sparing arteries. Histologically, there are acute lesions of lymphocytic and/or necrotizing, sometimes granulomatous phlebitis and chronic lesions of myointimal hyperplasia reducing the lumen of the veins. In this case, polymorphonuclear eosinophils were particularly numerous.


Asunto(s)
Colon/irrigación sanguínea , Intestino Delgado/irrigación sanguínea , Isquemia/patología , Oclusión Vascular Mesentérica/complicaciones , Anciano , Colon/patología , Resultado Fatal , Femenino , Humanos , Intestino Delgado/patología , Isquemia/etiología , Oclusión Vascular Mesentérica/patología , Venas Mesentéricas , Necrosis
10.
Ann Urol (Paris) ; 28(3): 139-41, 1994.
Artículo en Francés | MEDLINE | ID: mdl-8031020

RESUMEN

The authors report three cases of rectal linitis plastica which presented in a novel manner by urological manifestations. The diagnosis of these lesions was based essentially upon deep rectal, bladder and prostate biopsies as well as CT scan. These three clinical cases illustrate the dreadful prognosis of rectal linitis plastica, agreeing with conclusions emerging from a review of the literature.


Asunto(s)
Linitis Plástica/diagnóstico , Neoplasias del Recto/diagnóstico , Trastornos Urinarios/diagnóstico , Adenocarcinoma/diagnóstico , Adenocarcinoma/secundario , Anciano , Humanos , Linitis Plástica/secundario , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Neoplasias de la Vejiga Urinaria/diagnóstico , Incontinencia Urinaria/diagnóstico
11.
J Chir (Paris) ; 127(6-7): 325-9, 1990.
Artículo en Francés | MEDLINE | ID: mdl-2211890

RESUMEN

Consumption coagulopathy with clinical symptoms reveals aortic arterial aneurysm in less than 5%. Aneurysmal repair with graft is able to remove hemostasis abnormalities for a long time. The physiopathology of these abnormalities is described here through the study of an operated case. It is questionable to use heparinotherapy as exclusive treatment for non operated patients. Heparinotherapy during perioperative period is also a matter of debate. Surgical implications of the consumption coagulopathy are listed: preoperative plasma and platelets transfusions, fibrinogen and antithrombin III perfusions, meticulous hemostasis, minor dissection, use of a women graft. Coagulation disorders disappear before the first postoperative week. Persistent or recurrent consumption coagulopathy invite us to look for a pathological association which often turns out to be a neoplasm.


Asunto(s)
Aneurisma de la Aorta/complicaciones , Coagulación Intravascular Diseminada/etiología , Anciano , Aorta Abdominal , Aneurisma de la Aorta/diagnóstico , Aneurisma de la Aorta/cirugía , Prótesis Vascular , Coagulación Intravascular Diseminada/diagnóstico , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fibrinógeno/análisis , Heparina/uso terapéutico , Humanos , Recuento de Plaquetas
12.
Presse Med ; 17(5): 207-8, 1988 Feb 13.
Artículo en Francés | MEDLINE | ID: mdl-2965377

RESUMEN

An original procedure for treating major incisional hernias is described. A polyglactin 910 plate is hemmed around the edges of the hernia, then tightened by degrees with wide separate stitches until these edges are closely approximated on the midline under low tension, all the forces being distributed over the whole surface of the plate. This procedure can be used alone or associated with another procedure.


Asunto(s)
Hernia Ventral/cirugía , Poliglactina 910/uso terapéutico , Polímeros/uso terapéutico , Complicaciones Posoperatorias/cirugía , Humanos
14.
J Chir (Paris) ; 124(5): 311-4, 1987 May.
Artículo en Francés | MEDLINE | ID: mdl-3611229

RESUMEN

Seventy-five cases of primary carcinoma of the gallbladder are reviewed retrospectively under observation of a fifteen year period, representing 2.4 per cent of the number of biliary tract surgery performed during the same period. The majority of the patients presented with advanced disease with extension and metastases to the liver (56%) and to the adjacent organs (53.3%) and to the lymph nodes along the common bile duct (21.3%). Eleven patients had localized disease at the time of the operation; they were treated with cholecystectomy. Eight patients had clinically inapparent carcinoma at the time of the cholecystectomy; the diagnosis being established post-operatively by histologic examination of the excised gallbladder. There were no five years survivors in this second group of patients, but five of them are one year survival (62.5%) and one is still alive three years and six months after surgery. The remaining patients with inapparent carcinoma died within three years of the time of the operation. The present report emphasize the poor prognosis associated with carcinoma of the gallbladder and the presence of gallstones. Carcinoma of the gallbladder in our experience has proved curable only when accidentally discovered at cholecystectomy for presumed benign biliary tract disease. This fact plus the frequent and serious non neoplastic complications of neglected gallstones are strong indications for early elective cholecystectomy and extended resection may improve the survival rate.


Asunto(s)
Neoplasias de la Vesícula Biliar/cirugía , Adulto , Anciano , Colecistectomía , Colelitiasis/complicaciones , Femenino , Neoplasias de la Vesícula Biliar/complicaciones , Neoplasias de la Vesícula Biliar/diagnóstico , Humanos , Neoplasias Hepáticas/secundario , Metástasis Linfática , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
17.
Ann Urol (Paris) ; 18(5): 313-7, 1984 Sep.
Artículo en Francés | MEDLINE | ID: mdl-6529243

RESUMEN

Left ureteral stenosis induced by pancreatitis was observed in one case. Five similar cases have been reported in the literature. Ureteral obstructions may be found in two clinical contexts--patent pancreatitis or retroperitoneal fibrosis. The ureter may be simply compressed mechanically, or there may also be enzymatic or ischemic necrosis. The clinical approach should be directed towards treating primarily the pancreatitis and secondarily the urological pathology. As regards the urological treatment, ureterolysis or ilio-ureteroplasty are indicated in cases of organized irreversible ureteral stenosis.


Asunto(s)
Pancreatitis/complicaciones , Obstrucción Ureteral/etiología , Adulto , Constricción Patológica , Humanos , Masculino , Fibrosis Retroperitoneal/complicaciones , Uréter/patología , Obstrucción Ureteral/patología , Obstrucción Ureteral/cirugía
18.
Sem Hop ; 60(2): 113-8, 1984 Jan 19.
Artículo en Francés | MEDLINE | ID: mdl-6322325

RESUMEN

The authors analyze sixty-two cases of acute generalized peritonitis with a non-traumatic colonic etiology. They point out that the prognosis depends on three main factors: the age of the patient, the time spent in diagnosis and the therapeutic difficulties. They recommend a gastrographin colonic enema to obtain earlier diagnosis, in the absence of radiological evidence of pneumoperitoneum, in elderly patients presenting with abdominal signs. They also recommend multistage surgical management combining effective drainage of the abdominal cavity with resection of the perforated segment of the colon, whenever there is extensive damage to the colon, or in the presence of a tumor. In their view, conservative surgery should be confined to strictly selected cases not involving tissue resection. These indications are essential if a satisfactory result is to be achieved.


Asunto(s)
Colon , Perforación Intestinal/complicaciones , Peritonitis/etiología , Adulto , Anciano , Neoplasias del Colon/complicaciones , Divertículo del Colon/complicaciones , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Peritonitis/mortalidad , Peritonitis/cirugía
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