354 research outputs found

    The endometrial capillaries during the normal menstrual cycle: a morphometric study

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    The areas of the capillary lumen, the entire capillary, the endothelial cells and the adventitia, as well as the thickness of the endothelial cell layer and the adventitia were studied using morphometric methods in endometrial samples from 34 fertile women who had a hormonal profile compatible with normal ovarian function. The biopsies were grouped around the luteinizing hormone surge. The results were calculated as mean values of 72-h periods and related to the mean levels of oestradiol and progesterone circulating in plasma 72 h prior to the biopsy. The results indicated that the sub-epithelial capillary plexus of the human endometrium undergoes dynamic changes during the normal menstrual cycle with a significant dilatation of the vessels during the post-ovulatory phase. A significant correlation was found between the area of the capillary lumen and the mean level of progesterone circulating in the plasma 72 h prior to the biopsy (P = 0.037). We conclude that the ovarian steroids produced during the normal menstrual cycle are likely to influence sub-epithelial vascularization causing dilatation in the post-ovulatory phase. This dilatation of the sub-epithelial capillaries may be related to the development of oedema appearing in the stroma at the time of the expected implantation. The possible functional significance of the capillary dilatation in terms of implantation, however, needs to be further investigate

    Social Capital Impediments In The United Arab Emirates: A Case Of Emirati Female Entrepreneurs

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    It is possible that when looked at from the outside, the Gulf Arab countries give an impression that they are not very supportive to female entrepreneurs. This perception may be pertinent to a certain degree; however, Emirati female entrepreneurs (EFE) in the United Arab Emirates demonstrate that enhancing co-operation and support is possible through increasing interaction and networking with men. Analysis is undertaken of the observations and actions of conveniently selected 17 EFEs. The scoping of the respondents reveal that EFEs who engage with indirect male ties require a \u27male contact facilitator\u27 from their family or relatives to do so. These men are facilitated by the entrepreneur to adopt the role of a \u27male network partner (MNP) and provide support in overcoming challenges and achieving business objectives. The paper sets new standards of support for Emirati women in business ventures as it attempts to describe Emirati female entrepreneurship in a different language and proposes that co-operation, interaction and networking with men help EFEs access and use key resources, alleviate or remove key challenges and achieve business objectives

    Re-inventing artisanal knowledge and practice: a critical review of innovation in a craft-based industry

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    This paper presents a critical review of the ways in which the specialised knowledge and working practices of craft-based industries have been transformed in the context of broader processes of industrialisation and global competition. The opening section makes the case for artisanal knowledge as a ‘Cinderella’ subject that remains important yet largely uncharted territory for innovation researchers. It is followed by a critical review of existing empirical and theoretical studies that have examined the reproduction and reinvention of artisanal knowledge. The review concludes that valuable insights remain obscured due to the way in which this literature is distributed across discrete disciplines with little evidence of cross-fertilisation or integration. Several common themes emerge, which provide the basis for an outline theoretical framework. The central arguments are illustrated with reference to a case-based analysis of the technological and social innovations that have taken place in English farmhouse cheesemaking over an extended period, from the pre-industrial era to the beginning of the present century. The concluding section considers how more nuanced understandings of artisanal knowledge and practice might enhance innovation theory and contribute to the continued flourishing of craft-based industries

    Male pygmy hippopotamus influence offspring sex ratio

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    Pre-determining fetal sex is against the random and equal opportunity that both conceptus sexes have by nature. Yet, under a wide variety of circumstances, populations shift their birth sex ratio from the expected unity. Here we show, using fluorescence in situ hybridization, that in a population of pygmy hippopotamus (Choeropsis liberiensis) with 42.5% male offspring, males bias the ratio of X- and Y-chromosome-bearing spermatozoa in their ejaculates, resulting in a 0.4337±0.0094 (mean±s.d.) proportion of Y-chromosome-bearing spermatozoa. Three alternative hypotheses for the shifted population sex ratio were compared: female counteract male, female indifferent, or male and female in agreement. We conclude that there appears little or no antagonistic sexual conflict, unexpected by prevailing theories. Our results indicate that males possess a mechanism to adjust the ratio of X- and Y-chromosome-bearing spermatozoa in the ejaculate, thereby substantially expanding currently known male options in sexual conflict

    γδ T lymphocytes from cystic fibrosis patients and healthy donors are high TNF-α and IFN-γ-producers in response to Pseudomonas aeruginosa

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    BACKGROUND: γδ T cells have an important immunoregulatory and effector function through cytokine release. They are involved in the responses to Gram-negative bacterium and in protection of lung epithelium integrity. On the other hand, they have been implicated in airway inflammation. METHODS: The aim of the present work was to study intracytoplasmic IL-2, IL-4, IFN-γ and TNF-α production by γδ and αβ T lymphocytes from cystic fibrosis patients and healthy donors in response to Pseudomonas aeruginosa (PA). Flow cytometric detection was performed after peripheral blood mononuclear cells (PBMC) culture with a cytosolic extract from PA and restimulation with phorbol ester plus ionomycine. Proliferative responses, activation markers and receptor usage of γδ T cells were also evaluated. RESULTS: The highest production of cytokine was of TNF-α and IFN-γ, γδ being better producers than αβ. No differences were found between patients and controls. The Vγ9δ2 subset of γδ T cells was preferentially expanded. CD25 and CD45RO expression by the αβ T subset and PBMC proliferative response to PA were defective in cystic fibrosis lymphocytes. CONCLUSION: Our results support the hypothesis that γδ T lymphocytes play an important role in the immune response to PA and in the chronic inflammatory lung reaction in cystic fibrosis patients. They do not confirm the involvement of a supressed Th1 cytokine response in the pathogenesis of this disease
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