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1.
OBJECTIVES: The United Arab Emirates is witnessing a rapid development in population and infrastructure, leading to an expansion in the educational field and the health care system, including universities, hospitals and research institutes. One potential outcome of this development is an increase in biomedical research publications. This was examined in this study. METHOD: Searches were made of three databases; PubMed, Current Contents and embase. All records from these databases related to the Emirates were downloaded and cross-referenced. Duplications were removed as well as erroneous records. A total of 1369 publications during 1998-2004 were obtained. RESULTS: Analysis of these records revealed that the Faculty of Medicine and Health Sciences, located at the federal University, was responsible for 48% of all biomedical publications. All hospitals together accounted for 24%, while other universities and other research institutes accounted for 13 and 14% respectively. Further analysis revealed that there had been no further growth in the number of publications since 1998. This is in contrast to the increasing number of institutions that have been set up in the 1998-2004 period; from 29 to 112. CONCLUSION: The Emirates are witnessing a rapid development in universities, colleges, hospitals and research centres. The ratio of publications, as yet, has not kept up with this development. The enormous growth in institutes, however, may, in time, herald an Arabian renaissance in scientific activity and related publications.  相似文献   
2.
Friedman WJ 《Child development》2007,78(5):1472-1491
In two studies of knowledge about the properties and processes of memory for the times of past events, 178 children from 5 through 13 years of age and 40 adults answered questions about how they would remember times on different scales, how temporal memory is affected by retention interval, and the usefulness of different methods. The adults showed quite accurate knowledge about the main properties of memory for time and the processes that underlie it. Different properties and processes were first understood at ages ranging from 8 years to 12 years or later. Knowledge of the roles of reconstruction and impressions of temporal distances appear well after children use them to remember the times of events.  相似文献   
3.
Previous studies of the concept of entropy have indicated that before 7 to 9 years of age, children have difficulty understanding the effects of randomizing forces and often predict highly improbable events, such as a return to the original ordered state. In the present research, 306 children between 3 and 11 years of age were asked directly whether undifferentiated forces, such as the wind or objects being thrown into the air, could create order or disorder in a set of objects. The results showed that even 4-year-olds are sensitive to the asymmetrical effects of such events. Older children apply this principle more consistently and are able to use it in explaining their answers.  相似文献   
4.
This paper explores the association between moderate levels of physical activity (PA) and health benefits in well being and symptoms such as tiredness, back pain, and constipation. Participants in the Australian Longitudinal Study on Women's Health, 14,502 young women (ages 18-23 years), 13,609 middle-age women (45-50 years), and 11,421 older women (ages 70-75 years), answered questions about vigorous and less vigorous exercise (used to determine a physical activity score), well being (SF-36), symptoms, and medical conditions. There were significant associations between the PA score and SF-36 in each cohort. Odds ratios (OR) for a range of symptoms and conditions were lower for women who reported low to moderate activity than for sedentary women, for example, for young women or for constipation = 0.76 (CI, 0.65-0.89), for middle-age women or for tiredness = 0.70 (0.63-0.78). There was no threshold of PA at which health benefits increased significantly. Although cross-sectional, the findings suggest that low-to-moderate levels of exercise are associated with a range of health benefits for women of all ages. These preliminary findings will be followed up during the longitudinal study.  相似文献   
5.
Polyethylenimine-cyclodextrin-tegafur (PEI-CyD-tegafur) conjugate was synthesized as a novel multifunctional prodrug of tegafur for co-delivery of chemotherapeutic agent tegafur and enhanced green fluorescent protein (EGFP) reporter plasmid DNA. Conjugation of tegafur to PEI-CyD via chemical linkage was characterized by 1H NMR spectrometry and ultraviolet (UV) spectrometry. PEI-CyD-tegafur was able to condense plasmid DNA into complexes of around 150 nm with positive charge at the N/P ratio of 25, in accordance with electron microscopy observation of compact and monodisperse nanoparticles. The results of in vitro experiments showed enhanced cytotoxicity and considerable transfection efficiency in B16F10 cell line. Therefore, PEI-CyD-tegafur may have great potential as a co-delivery system with anti-cancer activity and potential for gene delivery.  相似文献   
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7.
不幸     
在《不幸》这篇短篇小说中.作者描述一个如同幽闭恐怖症患者般的孤独者,他有时注视窗外,有时心血来潮到街上散步,又总会遇到令人不满的事。这一次,他遇到了"一个小鬼",后者以一种突然的、戏剧性的方式闯进房间,于是两人展开了一段离奇的对话。这篇小说一方面讲述了不幸的人要求结交可能的朋友,另一方面则是对模糊的不安和恐惧的发泄。对社会的陌生感、孤独感与恐惧感,是卡夫卡创作的永恒主题。美国诗  相似文献   
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9.
Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR (MSP) and bisulfite sodium PCR (BSP), we found that its expression was associated with DNA hypomethylation of exonl. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2'-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the functional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony formation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1.  相似文献   
10.
This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency (45% and 36% respectively), as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium.  相似文献   
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