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91.
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
92.
Moore ML 《The Journal of perinatal education》2002,11(3):43-47
Misoprostol (Cytotec) is a synthetic prostaglandin E1 analogue that was designed for the prevention and treatment of peptic ulcer associated with the use of nonsteroidal anti-inflammatory drugs. In obstetrics, misoprostol has been administered for induction of first and second trimester abortion, for induction of labor in the third trimester, and to control postpartum hemorrhage. None of these uses has been approved by the Food and Drug Administration. Nevertheless, misoprostol is widely used in the United States and throughout the world. Advantages are cited as reduced rate of cesareans, shorter time from induction to birth and, particularly in developing countries, lower cost, oral, vaginal or rectal administration, and stability without refrigeration. Disadvantages are uterine hyperstimulation and, in rare instances, uterine rupture and death. Mothers should be informed of both the risks and the possible benefits of misoprostol. Further research with large samples is necessary to determine whether the risks outweigh any possible benefits. 相似文献
93.
The authors argue that the knowledge work metaphor is the most powerful image of schools for understanding reform. Using themes from the new management literature, such as shared decision making, collegiality, innovation, and experimentation, as additional guides for school improvement, the authors develop a case for systemic reform based on the professionalization of teaching and the integration of theory, research, and practice, Finally, transformational leadership is presented as the key to facilitating systemic reform. 相似文献
94.
鸢尾紫色素的提取与理化性质研究 总被引:2,自引:0,他引:2
以高原鸢尾花为原料,提取紫色色素,并对紫色色素的理化性质进行了研究。结果表明色素具有较好的稳定性,具有一定的开发利用价值。 相似文献
95.
Moore ML 《The Journal of perinatal education》2003,12(2):44-46
IN THIS COLUMN, THE AUTHOR EXAMINES RECENT RESEARCH ON TWO SEPARATE TOPICS: 1) breastfeeding; 2) postpartum length of hospital stay. Recent studies suggest long-term effects of breastfeeding that benefit both mother and infant. Benefits include a reduced risk of breast cancer in breastfeeding mothers and a reduced level of total and LDH cholesterol in adults who were breastfed as infants. Infants of mothers with maternal asthma had lower rates of asthma if the mother breastfed. In a study of women in the United States who planned to breastfeed, those mothers who breastfed exclusively and planned to breastfeed more than three months were more likely to achieve their goals than mothers who planned to combine breast and human-milk substitute feeds and to breastfeed less than three months.In a Canadian study, shortened postpartum stays led to increased re-admission to hospital for mothers with cesarean births. In contrast, in a Massachusetts study, shortened postpartum stays did not lead to an increase in infant visits for urgent care. However, the Massachusetts study did not reflect a decrease in maternity-related costs associated with shortened length of postpartum stay. 相似文献
96.
Hua-feng Wang Yi-zhi Cheng Huan-ping Wang Zhi-mei Chen Ji-yu Lou Jie Jin 《Journal of Zhejiang University. Science. B》2009,10(11):833-838
We report that a 63-year-old Chinese female had acute myeloblastic leukemia (AML) in which trisomy 21 (+21) was found as the
sole acquired karyotypic abnormality. The blasts were positive for myeloperoxidase, and the immunophenotype was positive for
cluster of differentiation 19 (CD19), CD33, CD34, and human leukocyte antigens (HLA)-DR. The chromosomal analysis of bone
marrow showed 47,XX,+21[2]/46,XX[18]. Fluorescent in situ hybridization (FISH) showed that three copies of AML1 were situated
in separate chromosomes, and that t(8;21) was negative. The patient did not have any features of Down syndrome. A diagnosis
of CD19-positive AML-M5 was established with trisomy 21 as a sole acquired karyotypic abnormality. The patient did not respond
well to chemotherapy and died three months after the diagnosis. This is the first reported case of CD19-positive AML with
trisomy 21 as the sole cytogenetic abnormality. The possible prognostic significance of the finding in AML with +21 as the
sole acquired karyotypic abnormality was discussed. 相似文献
97.
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99.
This article describes an interdisciplinary continuing education approach for health professionals in a rural remote area implemented by the Northern Educational Centre for Aging and Health (NECAH) at Lakehead University in Thunder Bay, Ontario, Canada. The article discusses issues of rural health care practice and the implications for practitioners’ educational needs. The key components involved in delivering interdisciplinary education and teamwork training are reviewed, followed by a discussion of the relevance of an interdisciplinary participatory approach for rural practitioners given their practice context and work style. Using NECAH's experience in planning and delivering a 5‐day interdisciplinary education program in palliative care as a case example, it is argued that simultanous attention to these issues in the design and delivery of continuing professional education for rural professionals contributes to a relevant educational experience in the short‐term and an increased interdisciplinary collaboration in the long‐term. The article suggests that NECAH's interdisciplinary participatory approach is a significant model for the continuing education of health professionals in rural remote areas. 相似文献
100.
小鹅瘟在国内已广泛流行,雏鹅的预防和治疗以鹅抗小鹅瘟血清较为理想,但若用山羊抗小鹅瘟血清,则可获得大量的血清及长时间采血且降低成本,经笔者研制的山羊抗血清具琼扩试验效价达1:16;保护试验保护率达80—100%小范围区域试验保护率达95%。 相似文献