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排序方式: 共有978条查询结果,搜索用时 15 毫秒
81.
随着专利数量的逐年大幅增长,获取有效目标专利的难度也越来越大,专利检索如何实现检准率和检全率的合理平衡成为研究难点。以德温特专利数据库中3G技术专利为检索对象,比较了传统主题检索和手工代码检索两种方式所对应检索及其分析结果的异同,研究表明选择合理的专利检索和分析方法有助于保证分析结果的权威性。 相似文献
82.
83.
本文通过比较原油价格变动对中国与西方发达国家经济增长影响,建立了原油价格变动影响经济增长的国际传导机制模型,研究结论包括:(1)当期原油价格上涨对中国经济增长率有显著的负向影响;(2)当期原油价格上涨对西方七国增长率有正向影响,不过这个结论在统计上不显著;(3)滞后1、2期的原油价格上涨对当期西方国家经济增长率有显著的负向影响;(4)当期中国经济结构变动在5%的显著性水平下影响中国经济增长率,在10%的显著性水平下影响西方七国经济增长率;(5)中国经济增长率对西方国家的经济增长有长期的正向影响,影响时间持续3年以上;(6)西方七国经济增长对中国经济增长有负向影响,影响时期持续两年以上。根据上述结论本文认为稳定的原油价格是中国和西方国家的共同责任,因为彼此的利益已经如此紧密相联。 相似文献
84.
Zhao-liang Xin Xiao-kang Wu Jian-rong Xu Xi Li 《Journal of Zhejiang University. Science. B》2010,11(7):516-523
Objective: To assess if arachnoid cells have the capability to present antigen and activate T-lymphocytes after stimulation by bloody cerebrospinal fluid (CSF), and to illuminate the mechanism of coagulation-initiated inflammation in the subarachnoid space after subarachnoid hemorrhage (SAH). Methods: Arachnoid cells were cultured, characterized, and examined by immunofluorescence for the basal expression of human leukocyte antigen-DR (HLA-DR). Expression of HLA-DR, after co-culturing arachnoid cells in vitro with bloody CSF, was investigated by immunofluorescence and flow cytometry (FCM). The variation of arachnoid cells' ultrastructure was observed by transmission electron microscope (TEM). Arachnoid cells were co-cultured with peripheral blood mononuclear cells (PBMCs). The content of soluble interleukin-2 receptor (sIL-2r) in culture medium was detected by enzyme-linked immunosorbent assay (ELISA). Results: (1) Arachnoid cells were successfully cultured for many passages. The immunofluorescent staining was positive for HLA-DR in over 95% of the human arachnoid cells. The punctate HLA-DR was distributed in cytoplasm and not in the karyon. (2) After co-culturing arachnoid cells in vitro with bloody CSF, numerous particles with strong fluorescence appeared in the cytoplasm on Day 6. On Day 8, the quantity of particles and fluorescent intensity were maximal. FCM showed that the percentage of HLA-DR expressing cells was (2.5±0.4)% at the first 5 d, increasing to (60.8±3.6)% on Day 7. (3) After co-culturing arachnoid cells in vitro with bloody CSF, many lysosome and secondary lysosome particles were present in the cytoplasm. Hyperplasia of rough endoplasmic reticulum and enlarged cysts were observed, with numerous phagocytizing vesicles also observed at the edge of the arachnoid cells. (4) Arachnoid cells stimulated by bloody CSF were co-cultured in vitro with PBMCs. The content of sIL-2r in the culture medium, having been maintained at around 1.30 ng/ml during the first 3 d, had increased by Day 4. The content of sIL-2r peaked 7.53 ng/ml on Day 7 and then reduced gradually. Conclusions: (1) Basic HLA-DR expression is present in arachnoid cells. (2) After stimulation by bloody CSF, arachnoid cells have the potential to serve as antigen presenting cells (APCs) and the ability to activate T-lymphocytes, indicating that arachnoid cells are involved in the mechanism of coagulation-initiated inflammation in the subarachnoid space after SAH. 相似文献
85.
Wang ZF Ying TJ Zhang Y Bao BL Huang XD 《Journal of Zhejiang University. Science. B》2006,7(7):591-595
Two stable transformed lines containing antisense LeERT1 or LeERT2 sequences and their hybridized line were investigated to determine the effect of LeERT1 and LeERT2 specificity in the ethylene receptor family in tomato (Lycopersicon esculenturn Mill.) on ethylene signaling. The transgenic line alel containing antisense LeER T1 displayed shorter length of seedling grown in the dark and adult plant in the light, severe epinastic petiole, and accelerated abscission of petiole explant and senescence of flower explant, compared with its wild type B 1. The transgenic line ale2 containing antisense LeERT2 also exhibited shorter hypocotyls and slightly accelerated abscission. The phenotypes of cross line dale of LeERT1 and LeERT2 were close to alel in many aspects. These results suggested that LeERT1 probably plays a relatively important role in ethylene signaling of tomato growth and development. 相似文献
86.
Susan Kiragu 《Sex education》2013,13(5):585-596
Based on oral history accounts elicited from 25 G?k?y? elders in Kenya, this paper describes a non-penetrative sexual practice, ngweko, permitted for the sake of pleasure and sexual release among circumcised and unmarried young people in the G?k?y? community. Lessons that can be learned from the pre-colonial G?k?y? sexuality culture are identified, and possible implications for contemporary sexuality education explored. 相似文献
87.
高尚风 《乐山师范学院学报》2013,(4):36-41
英国作家詹·格·巴拉德在《太阳帝国》中塑造了沉默的中国人形象,他对战争阴霾下的上海的描写,是为了借对"他者"的否定和批判肯定自身。巴拉德对中国形象的塑造采取了意识形态化的策略,在他建构的中国形象背后,则是对自身民族身份的认同困惑,还有隐蔽的帝国主义思想和殖民意图。 相似文献
88.
王凤岭 《南宁职业技术学院学报》2013,(6):86-89
本装置是综合运用3G技术、指纹识别技术和嵌入式技术等研发的一种远程无线身份认证系统。用3G通信方式可以不受位置的限制,比Internet方式更灵活,且3G带宽比普通的RJ45接口网络连接速度更快。本装置成本低廉,安全可靠,实用性强,具有广泛的应用和推广价值。 相似文献
89.
杨立波 《洛阳师范学院学报》2013,(11):9-11
对G'/G展开法进行了扩展,并将该方法应用到非线性差分微分方程的求解领域,通过借助符号计算系统Mathematica,得到了修正的Volterra格子方程的多组含参的新的精确解,包括双曲函数解、三角函数解和有理函数解. 相似文献
90.
朱永平 《商丘师范学院学报》2013,(9):6-9
利用( G′G+G′)展开法,借助Maple软件的符号运算功能,研究了BBM方程和Burgers-BBM方程,获得了BBM方程和Burgers-BBM方程的与现有文献不同的精确解,从而丰富了解的范围。 相似文献