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In recent years, the first attempts have been made to apply gene transfer technology to protect neurons from death following neurological insults. There has been sufficient progress in this area that it becomes plausible to consider similar gene therapy approaches meant to delay aspects of aging of the nervous system. In this review, we briefly consider such progress and how it might be applied to the realm of the aging brain. Specifically, we consider: (a) the means of delivery of such therapeutic genes; (b) the choice of such genes; and (c) technical elaborations in gene delivery systems which can more tightly regulate the magnitude and duration of transgene protection. 相似文献
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Ogle BM Dao HT Mulokozi G Hambraeus L 《International journal of food sciences and nutrition》2001,52(6):485-499
This article presents the nutrient composition and nutritional contribution of naturally occurring vegetables (NOV) in four villages in Vietnam. The frequency of consumption and quantities eaten were evaluated within the overall diet of 101 and 110 women in the Mekong Delta (flood period and rainy season, respectively) and of 103 women in the Central Highlands (rainy season). The concentrations of Ca, Fe and Zn were analysed in 28 species, and presence of tannins and phytic acid in 19 species. Provitamin carotenoids were determined in 11 species. Over 90% of the women consumed NOV, and they contributed 43, 72 and 75% (Central Highlands, Mekong rainy and Mekong flood period, respectively) of the total quantities of vegetables eaten. Aquatic species such as lpomoea aquatica and Limnocharis flava, and terrestrial vegetables such as Schismattoglottis calyptrata, were among the most commonly consumed vegetables. They were eaten in mean daily quantities exceeding 50 g and had high concentrations of Ca, Fe and beta-carotene. Other major aquatic vegetables included the stems of Eleocharis sp., Nelumbo nucifera and Nymphea lotus, all of which were used as salad vegetables and had relatively low nutrient density. The problems of assessing the current role of NOV due to lack of data on intakes in the context of the overall diets, as well as data on their composition, are addressed. 相似文献
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Medical students are usually drawn from the best of students, but it is not unusual to see these brilliant students fail their exams or even dismissed from medical school because of poor academic performance. Information overload has been recognized as one of the major contributing factors to this problem. The situation is expected to get worse, with the ever-present technology-induced exponential growth in information. In discussing this issue, the authors echo the concerns of several experts regarding the content overload of medical school curricula, particularly in pharmacology. It is the increasing awareness of this problem that led the Association of American Medical Colleges and the General Medical Council of Britain to promote the concept of a core curriculum for each of the principal disciplines in medicine. Several medical schools have adopted the concept and also the problem-based learning approach, which focuses on ameliorating the complex problems associated with information growth in medical education. Based on the authors' experience as medical students, medical practitioners, and pharmacology teachers, they discuss the factors that contribute to information overload, from psychological and nonpsychological perspectives. Issues such as the design and structure of the curriculum, the quality of training and effectiveness of the teachers (clinically qualified vs. nonclinically qualified teachers), and the psychological preparedness of the students are discussed. The authors make suggestions for improvement. 相似文献
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RS de Vreeze D de Jong IH Tielen HJ Ruijter PM Nederlof RL Haas F van Coevorden 《Modern pathology》2009,22(2):223-231
Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum. 相似文献
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The effects of an ethanol extract of the plant Sophora flavescens Ait. on haemodynamics and ventricular fibrillation threshold were studied in pentobarbitone-anaesthetized dogs. It was found that intravenous injection of the extract, 120 mg/kg, caused transient but significant depression in systolic and diastolic blood pressure, heart rate, left ventricular pressure and dLVP/dtmax, as well as elevation of ventricular fibrillation threshold. These preliminary findings suggest that the ethanol extract of Sophora flavescens Ait. possesses pharmacological activities resembling those of antiarrhythmic agents, but the mechanisms of action are unclear. 相似文献