799 resultados para Human anatomy -- Study and teaching (Higher)
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Transgenic mice carrying heterologous genes directed by a 670-bp segment of the regulatory sequence from the human transferrin (TF) gene demonstrated high expression in brain. Mice carrying the chimeric 0.67kbTF-CAT gene expressed TF-CAT in neurons and glial cells of the nucleus basalis, the cerebrum, corpus callosum, cerebellum, and hippocampus. In brains from two independent TF-CAT transgenic founder lines, copy number of TF-CAT mRNA exceeded the number of mRNA transcripts encoding either mouse endogenous transferrin or mouse endogenous amyloid precursor protein. In two transgenic founder lines, the chloramphenicol acetyltransferase (CAT) protein synthesized from the TF-CAT mRNA was estimated to be 0.10-0.15% of the total soluble proteins of the brain. High expression observed in brain indicates that the 0.67kbTF promoter is a promising director of brain expression of heterologous genes. Therefore, the promoter has been used to express the three common human apolipoprotein E (apoE) alleles in transgenic mouse brains. The apoE alleles have been implicated in the expression of Alzheimer disease, and the human apoE isoforms are reported to interact with different affinities to the brain beta-amyloid and tau protein in vitro. Results of this study demonstrate high expression and production of human apoE proteins in transgenic mouse brains. The model may be used to characterize the interaction of human apoE isoforms with other brain proteins and provide information helpful in designing therapeutic strategies for Alzheimer disease.
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Estradiol is converted to catechol estrogens via 2- and 4-hydroxylation by cytochrome P450 enzymes. 4-Hydroxyestradiol elicits biological activities distinct from estradiol, most notably an oxidant stress response induced by free radicals generated by metabolic redox cycling reactions. In this study, we have examined 2- and 4-hydroxylation of estradiol by microsomes of human uterine myometrium and of associated myomata. In all eight cases studied, estradiol 4-hydroxylation by myoma has been substantially elevated relative to surrounding myometrial tissue (minimum, 2-fold; mean, 5-fold). Estradiol 2-hydroxylation in myomata occurs at much lower rates than 4-hydroxylation (ratio of 4-hydroxyestradiol/2-hydroxyestradiol, 7.9 +/- 1.4) and does not significantly differ from rates in surrounding myometrial tissue. Rates of myometrial 2-hydroxylation of estradiol were also not significantly different from values in patients without myomata. We have used various inhibitors to establish that 4-hydroxylation is catalyzed by a completely different cytochrome P450 than 2-hydroxylation. In myoma, alpha-naphthoflavone and a set of ethynyl polycyclic hydrocarbon inhibitors (5 microM) each inhibited 4-hydroxylation more efficiently (up to 90%) than 2-hydroxylation (up to 40%), indicating > 10-fold differences in Ki (<0.5 microM vs. > 5 microM). These activities were clearly distinguished from the selective 2-hydroxylation of estradiol in placenta by aromatase reported previously (low Km, inhibition by Fadrozole hydrochloride or ICI D1033). 4-Hydroxylation was also selectively inhibited relative to 2-hydroxylation by antibodies raised against cytochrome P450 IB1 (rat) (53 vs. 17%). These data indicate that specific 4-hydroxylation of estradiol in human uterine tissues is catalyzed by a form(s) of cytochrome P450 related to P450 IB1, which contribute(s) little to 2-hydroxylation. This enzyme(s) is therefore a marker for uterine myomata and may play a role in the etiology of the tumor.
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Some would argue that there is a need for the traditional lecture format to be rethought in favour of a more active approach. However, this must form part of a bipartite strategy, considered in conjunction with the layout of any new space to facilitate alternative learning and teaching methods. With this in mind, this paper begins to examine the impact of the learning environment on the student learning experience, specifically focusing on students studying on the Architectural Technology and Management programme at Ulster University. The aim of this study is two-fold: to increase understanding of the impact of learning space layout, by taking a student centered approach; and to gain an appreciation of how technology can impact upon the learning space. The study forms part of a wider project being undertaken at Ulster University known as the Learning Landscape Transition Project, exploring the relationship between learning, teaching and space layout. Data collection was both qualitative and quantitative, with use of a case study supported by a questionnaire based on attitudinal scaling. A focus group was also used to further analyse the key trends resulting from the questionnaire. The initial results suggest that the learning environment, and the technology within it, can not only play an important part in the overall learning experience of the student, but also assist with preparation for the working environment to be experienced in professional life.
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Contains notes taken by Harvard student Lyman Spalding during eleven chemistry lectures delivered by Harvard Professor Aaron Dexter (1750-1829) in the fall of 1795 and recipes prepared and used by Spalding in his medical practice in 1797. The recipes include elixir vitriol, containing liquor, Jamaica pepper, cinnamon, and ginger, and an electuary for a cough, containing oxymel squills (sea onion in honey), licorice, antimonium tartaricum potash (a compound of the chemical element antimony and a potassium-containing salt), and opium. The volume also contains writings about chemistry by Spalding, some of which appear transcribed from published sources, in undated entries, and a diary entry from 1799 regarding an experiment with water.
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Contains notes taken by Harvard student Lyman Spalding from lectures delivered by Hersey Professor of the Theory and Practice of Physic Benjamin Waterhouse (1754-1846) in 1795. The notes cover the history of medicine, theories of contemporary physicians like Herman Boerhaave, William Cullen, and John Brown, and topics like fetal growth, digestion, and circulation. The volume also contains six pages of patient case notes from Spalding’s medical practice in Walpole, New Hampshire, in 1799, which detail the patients’ symptoms and course of treatment he pursued. In the case of a young man who complained of pain in his breast following a wrestling match, Spalding bled him and prescribed a cathartic of soap and aloes. Spalding also operated on a man who cut off part of his ankle with an ax.
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Mode of access: Internet.
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Mode of access: Internet.
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Includes bibliography.
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Mode of access: Internet.
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"A William Wood book."
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Mode of access: Internet.
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"References": p. 481-482.
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Mode of access: Internet.
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Mode of access: Internet.
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"The research reported ... was performed pursuant to Contract no. 8143 with the cooperative research Branch, United States Office of Education, Department of Health, Education, and Welfare."