1000 resultados para 7140-331


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A comparison of the site distribution of cutaneous malignant melanoma in New Zealand and Canada was performed. This series deals with 41,331 incident cases registered between 1968 and 1990 and is the largest to date to evaluate the influence of age and gender on the site distribution of melanoma. Site-specific, age-standardized rates per unit surface area and relative tumour density were assessed by gender and country and differences compared with statistical techniques adapted to this context. The age-standardized rates for all sites were higher in New Zealand than in Canada, the ratio being 3.2 for men and 3.8 for women. Occurrence of melanoma was denser for chronically than intermittently exposed sites in both New Zealand and Canada. The highest incidence rate per unit area was for the ears in men which was more than 5 times the rate for the entire body in each country. For each gender, melanomas were relatively commoner on the trunk and the face in Canada, and on the lower limbs in New Zealand. The variations in the site distribution were similar in each country and consistent with the effect of differential patterns of sun exposure between genders. Our results show that the levels of risk of melanoma between phenotypically comparable populations exposed to different amount of UV radiation vary in a site-specific manner, especially for intermittently exposed sites. This suggests that both environmental conditions and lifestyle factors influence the site distribution of melanoma in these two populations.

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Introduction: Primary bone sarcomas around the ankle are rare. Due to the proximity of neurovascular structures and limited soft tissue reserves, limb salvage is often not possible. Case report: A 19 yo male presented with pain and a progressive swelling of his ankle. X-rays revealed cortical erosions and an extensive periosteal reaction (sunburst) of the distal fibula. MRI showed a large mass of the fibula invading adjacent soft tissue. The lesion appeared close to the ankle joint, but with the articular cartilage as a barrier and without joint effusion. Core-needle biopsy revealed a high-grade chondroblastic osteosarcoma. No metastases were detected. After presentation at our multidisciplinary sarcoma board, the patient was subjected to neo-adjuvant chemotherapy (AOST 03-331). Without any sign of intra-articular contamination of the ankle joint, surgical treatment consisted of wide resection of the lateral malleolus including a large skin patch, the distal third of the fibula, the lateral surfaces of the tibia and talus as well as the insertion of the lateral ligament on the calcaneus. The distal parts of the anterior, peroneal, and posterior muscular compartments were resected en bloc with the tumor. The defect was reconstructed with tibio-talar and talo-calcanear fusion, bony allograft and a plate. Soft-tissue coverage was achieved with a free fascio-cutaneous flap from the controlateral thigh. Histological analysis revealed clear margins and 50% of tumor necrosis. The oncologic treatment was completed with adjuvant chemotherapy. Conclusion: Wide resection and reconstruction of the lateral malleolus is technically demanding but possible in selected cases. Despite some important functional loss, limb salvage is superior to an amputation.

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Recent studies indicate that directional female mate choice and order-dependent female mate choice importantly contribute to non-random mating patterns. In species where females prefer larger sized males, disentangling different hypotheses leading to non-random mating patterns is especially difficult, given that male size usually correlates with behaviours that may lead to non-random mating (e.g. size-dependent emergence from hibernation, male fighting ability). Here we investigate female mate choice and order-dependent female mate choice in the polygynandrous common lizard (Lacerta vivipara). By sequentially presenting males in random order to females, we exclude non-random mating patterns potentially arising due to intra-sexual selection (e.g. male-male competition), trait-dependent encounter probabilities, trait-dependent conspicuousness, or trait-dependent emergence from hibernation. To test for order-dependent female mate choice we investigate whether the previous mating history affects female choice. We show that body size and body condition of the male with which a female mated for the first time were bigger and better, respectively, than the average body size and body condition of the rejected males. There was a negative correlation between body sizes of first and second copulating males. This indicates that female mate choice is dependent on the previous mating history and it shows that the female's choice criteria are non-static, i.e. non-directional. Our study therefore suggests that context-dependent female mate choice may not only arise due to genotype-environment interactions, but also due to other female mating strategies, i.e. order-dependent mate choice. Thus context-dependent female mate choice might be more frequent than previously thought.

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The benefit of polymeric immuno-nanoparticles (NPs-Tx-HER), consisting of paclitaxel (Tx)-loaded nanoparticles coated with anti-HER2 monoclonal antibodies (Herceptin, trastuzumab), in cancer treatment was assessed in a disseminated xenograft ovarian cancer model induced by intraperitoneal inoculation of SKOV-3 cells overexpressing HER2 antigens. The study was focused on the evaluation of therapeutic efficacy and biodistribution of NPs-Tx-HER compared to other Tx formulations. The therapeutic efficacy was determined by two methods: bioluminescence imaging and survival rate. The treatment regimen consisted in an initial dose of 20mg/kg Tx administered as 10mg/kg intravenously (IV) and 10mg/kg intraperitonealy (IP), followed by five alternative IP and IV injections of 10mg/kg Tx every 3 days. The bioluminescence study has clearly shown the superior anti-tumor activity of NPs-Tx-HER compared to free Tx. As a confirmation of these results, a significantly longer survival of mice was observed for NPs-Tx-HER treatment compared to free Tx, Tx-loaded nanoparticles coated with an irrelevant mAb (Mabthera, rituximab) or Herceptin alone, indicating the potential of immuno-nanoparticles in cancer treatment. The biodistribution pattern of Tx was assessed on healthy and tumor bearing mice after IV or IP administration. An equivalent biodistribution profile was observed in healthy mice for Tx encapsulated either in uncoated nanoparticles (NPs-Tx) or in NPs-Tx-HER. No significant difference in Tx biodistribution was observed after IV or IP injection, except for a lower accumulation in the lungs when NPs were administered by IP. Encapsulated Tx accumulated in the organs of the reticulo-endothelial system (RES) such as the liver and spleen, whereas free Tx had a non-specific distribution in all tested organs. Compared to free Tx, the single dose injection (IV or IP) of encapsulated Tx in mice bearing tumors induced a higher tumor accumulation. However, no difference in overall tumor accumulation between NPs-Tx-HER and NPs-Tx was observed. In conclusion, the encapsulation of Tx into NPs-Tx-HER immuno-nanoparticles resulted in an improved efficacy of drug in the treatment of disseminated ovarian cancer overexpressing HER2 receptors.

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When deciding to resort to a PPP contract for the provision of a local public service, local governments have to consider the demand risk allocation between the contracting parties. In this article, I investigate the effects of demand risk allocation on the accountability of procuring authorities regarding consumers changing demand, as well as on the cost-reducing effort incentives of the private public-service provider. I show that contracts in which the private provider bears demand risk motivate more the public authority from responding to customer needs. This is due to the fact that consumers are empowered when the private provider bears demand risk, that is, they have the possibility to oust the private provider in case of non-satisfaction with the service provision, which provides procuring authorities with more credibility in side-trading and then more incentives to be responsive. As a consequence, I show that there is a lower matching with consumers' preferences over time when demand risk is on the public authority rather than on the private provider, and this is corroborated in the light of two famous case studies. However, contracts in which the private provider does not bear demand risk motivate more the private provider from investing in cost-reducing efforts. I highlight then a tradeoff in the allocation of demand risk between productive and allocative efficiency. The striking policy implication of this article for local governments would be that the current trend towards a greater resort to contracts where private providers bear little or no demand risk may not be optimal. Local governments should impose demand risk on private providers within PPP contracts when they expect that consumers' preferences over the service provision will change over time.

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This paper investigates relationships between cooperation, R&D, innovation and productivity in Spanish firms. It uses a large sample of firm-level micro-data and applies an extended structural model that aims to explain the effects of cooperation on R&D investment, of R&D investment on output innovation, and of innovation on firms’ productivity levels. It also analyses the determinants of R&D cooperation. Firms’ technology level is taken into account in order to analyse the differences between high-tech and low-tech firms, both in the industrial and service sectors. The database used was the Technological Innovation Panel (PITEC) for the period 2004-2010. Empirical results show that firms which cooperate in innovative activities are more likely to invest in R&D in subsequent years. As expected, R&D investment has a positive impact on the probability of generating an innovation, in terms of both product and process, for manufacturing firms. Finally, innovation output has a positive impact on firms’ productivity, being greater in process innovations.

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Este trabajo trata sobre la edad a la que niños y niñas accedían al trabajo remunerado en la España del siglo XVIII. Utilizando como fuente los Memoriales del Catastro de Ensenada (1751-1753), se propone la edad de diez años como edad media de acceso, a partir de la cual se puede calcular la tasa de actividad. La Mancha era una región rica en industria rural, sobre todo de manufacturas textiles, que abastecían al mercado madrileño, el de otras ciudades e incluso al colonial, y que generaban una fuerte demanda de trabajo femenino. Esta estructura productiva explica por qué las niñas se incorporaban al trabajo remunerado antes que los niños, por qué eran escolarizadas desde muy pequeñas en las ‘escuelas de labor’ y no en las escuelas de primeras letras como los niños, y por qué, en definitiva, sus tasas de alfabetización un siglo después eran inferiores a la ya muy baja media femenina española. En la España del siglo XVIII mujeres y niñas estaban masivamente empleadas en las manufacturas, sobre todo textiles, como ocurría en gran parte de Europa. Entender y contabilizar el trabajo realizado por mujeres y niñas, mucho más difundido de lo que se cree habitualmente, y centrado en manufacturas y servicios, transforma nuestra visión de la estructura de la actividad en la España pre-industrial, normalmente identificada con el trabajo agrícola y ganadero.

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Purpose (1) To identify work related stressors that are associated with psychiatric symptoms in a Swiss sample of policemen and (2) to develop a model for identifying officers at risk for developing mental health problems. Method The study design is cross sectional. A total of 354 male police officers answered a questionnaire assessing a wide spectrum of work related stressors. Psychiatric symptoms were assessed using the "TST questionnaire" (Langner in J Health Hum Behav 4, 269-276, 1962). Logistic regression with backward procedure was used to identify a set of variables collectively associated with high scores for psychiatric symptoms. Results A total of 42 (11.9%) officers had a high score for psychiatric symptoms. Nearly all potential stressors considered were significantly associated (at P < 0.05) with a high score for psychiatric symptoms. A significant model including 6 independent variables was identified: lack of support from superior and organization OR = 3.58 (1.58-8.13), self perception of bad quality work OR = 2.99 (1.35-6.59), inadequate work schedule OR = 2.84 (1.22-6.62), high mental/intellectual demand OR = 2.56 (1.12-5.86), age (in decades) OR = 1.82 (1.21-2.73), and score for physical environment complaints OR = 1.30 (1.03-1.64). Conclusions Most of work stressors considered are associated with psychiatric symptoms. Prevention should target the most frequent stressors with high association to symptoms. Complaints of police officers about stressors should receive proper consideration by the management of public administration. Such complaints might be the expression of psychiatric caseness requiring medical assistance. Particular attention should be given to police officers complaining about many stressors identified in this study's multiple model. [Authors]

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O objetivo deste trabalho foi investigar a eficiência de diferentes métodos, para a obtenção de estimativas dos parâmetros de adaptabilidade e estabilidade de 20 linhagens de feijão, em dois ensaios de valor de cultivo e uso, um com linhagens de feijão do grupo preto e outro do grupo carioca, conduzidos nas três safras tradicionais, em seis municípios do Estado de Minas Gerais, perfazendo 14 ambientes, nos anos de 2002 e 2003. Na recomendação dessas linhagens destacou-se o método de Carneiro, em razão da unicidade da medida de adaptabilidade e estabilidade de comportamento, que englobou os conceitos de adaptação, adaptabilidade e estabilidade, indicando as linhagens Ouro Negro e Vi 5700 (grupo preto) e OP-NS-331, Vi 4899 e Vi 0669 (grupo carioca) como de adaptabilidade geral. As linhagens Valente e VP1, do grupo preto, e OP-S-82, VC2 e OP-S-16, do grupo carioca, apresentaram adaptabilidade específica às condições favoráveis. Nas condições desfavoráveis, destacaram-se as linhagens Vi 5500 e VP5, do grupo preto, e VC4, VC5 e Vi 4599, do grupo carioca.

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Una gran parte de las empresas de todo el mundo, y especialmente las PYMES occidentales, están perdiendo mucho dinero, y como consecuencia de ello gran parte de su competitividad potencial, debido a que los costes totales de calidad en que incurren, son inaceptablemente elevados. En la mayoría de los casos no existe modelo coherente alguno para gestionar dichos costes, y en otros, los modelos aplicados se utilizan de forma parcial, rutinaria y con escaso convencimiento. El resultado de ello, como cabría esperar, es obviamente decepcionante. Evidentemente hay también empresas, generalmente las de gran tamaño (líderes del mercado y multinacionales), conocedoras de la gran importancia que para la disminución de sus costes supone disponer de un sistema adecuado de gestión de los costes de calidad. Invierten sistemáticamente en ello, obteniendo resultados satisfactorios, tanto en sus cuentas de resultados como en el nivel de motivación de sus empleados. Éstos, conscientes del interés de la Dirección por mejorar la calidad de sus productos y servicios, se sienten de alguna manera partícipes de ese proyecto, entendiendo que, en definitiva, el éxito de la empresa es también el suyo propio. Hemos analizado las causas de esta situación, utilizando las experiencias plasmadas en numerosos estudios llevados a cabo por expertos internacionales. Una vez localizados, acotados y definidos los aspectos débiles de los procedimientos aplicados en la actualidad, hemos diseñado un par de nuevos modelos de gestión de los costes totales de calidad, que tienen la virtud de haber eliminado aquellas etapas que, en la práctica, se han mostrado ineficaces, e incorporando otras, que han resultado ser muy útiles en diversos campos de la gestión de la calidad. El primero de los modelos, el más simple, puede ser utilizado para gestionar presupuestos de costes de calidad sencillos, mientras que el segundo contempla la posibilidad de lograr una mayor exactitud en las cifras de las previsiones, al tiempo que introduce alguna situación de incertidumbre.