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排序方式: 共有537条查询结果,搜索用时 15 毫秒
151.
Eric Wang Li Xiaoke 《中外文化交流(英文版)》2007,(2):14-17
Artist and photographer Li Xiaoke grew up looking to his father as a role model. But ,growing up in the shadow of the great modem master of traditional Chinese landscape ink and water painting, brought its own particular burden. Now in his sixties, the son has established his own place in the Chinese world of fine arts and photography, and created his own artistic vision.[第一段] 相似文献
152.
Li Chen Liu Jinbiao 《中外文化交流(英文版)》2006,(7):12-15
Thanks to its even terrains, fertile land suited for the growth of varieties of crops and its rich reserve of natural resources, Lizhuang attracted many immigrants from other provinces in the immigration boom taking place during the late Ming and early Qing dynasties (approx. 16th - 18th centuries). In order to protect their own interests, immigrants gradually established guilds, communities composed of people from certain trades or geographic origins. 相似文献
153.
Translation means the conversion of an expression into another language. To say plainly,It is an art to reproduce the exact idea of the author by means of a language different from the original.So the original thought of the expression must be kept as exactly as possible. The duty of the translator is simply to change the vocabulary not the thought. Literal translation and free translation are two essential ways in translation. Literal translation refers to an adequate representation of the original in sequence of vocabulary, in grammatical structure and rhetorical device. Free translation is also called liberal translation, which does not adhere strictly to the form or word order of the original. Which one is preferable? We can hardly say. Each has its advantages and disadvantages.Argument between them has been more than 80 years. What on earth is the argument? What do they focus on? The argument brings great effect to us, so I want to find some answers to it. 相似文献
154.
BRAIN NATRIURETIC PEPTIDE Several studies demonstrated that the heart is an endocrine organ (Henry and Pearce, 1956; Kisch, 1956; de Bold, 1985; de Bold et al., 1981; 1996; 2001). Atrial natriuretic peptide (ANP) was the first cardiac hormone identified in 1984 (Kangawa et al., 1984; de Bold et al., 1981). Later on, a new com- pound from pig brain was found, which had similar natriuretic and diuretic effects as ANP (Sudoh et al., 1988). This peptide was named brain (B-type) natr… 相似文献
155.
Li FZ Jin SH Hu GC Fu YP Si HM Jiang DA Sun ZX 《Journal of Zhejiang University. Science. B》2005,6(8):803-811
A rice pse(t) (premature senescence, tentatively) mutant line, was isolated from 4500 independent T-DNA inserted transgenic lines. The symptoms of premature senescence appeared more severely than those of the control plants (Zhonghua 11,japonica) at the last development stage. To characterize the mutant and provide basic information on the candidate genes by mapping to a physical region of 220-kb, experiments were carried out in two phytotrons under controlled temperature of 24 ℃ and28 ℃, respectively. The content of chlorophyll, soluble protein and MDA (malondialdehyde), net photosynthesis, the antioxidant enzyme activities of SOD (superoxide dismuase) (EC 1.15.1.1) and POD (peroxidase) (EC 1.11.1.7) and the peptidase activities of leaves were measured from top to bottom according to the leaf positions at the flowering stage. Compared with the control plant,the mutant showed the following characteristics: (1) Higher net photosynthesis rate (Pn) appeared in the 1 st and 2nd leaves, contents of chlorophyll and soluble protein were also higher in the 1 st leaf; (2) The activities of SOD, POD and peptidase were higher according to the leaf position from top to bottom; (3) The symptom of premature senescence was accelerated in the mutant at 28℃treatment. The MDA content and the SOD and POD activities between the 24 ℃ and 28 ℃ treatment mutants were not significantly different. Content of chlorophyll and soluble protein of leaves mutant decreased rapidly at 28 ℃ treatment. The results show that pse(t) is sensitive to high temperature. The probable function of PSE(T) is discussed. 相似文献
156.
Xu YX Li YL Xu SC Liu Y Wang X Tang JW 《Journal of Zhejiang University. Science. B》2008,9(7):558-566
Objective: To study the optimal medium composition for xylanase production by Aspergillus niger XY-1 in solid-state fermentation (SSF). Methods: Statistical methodology including the Plackett-Burman design (PBD) and the central composite design (CCD) was employed to investigate the individual crucial component of the medium that significantly affected the enzyme yield. Results: Firstly, NaNO3, yeast extract, urea, Na2CO3, MgSO4, peptone and (NH4)2SO4 were screened as the significant factors positively affecting the xylanase production by PBD. Secondly, by valuating the nitrogen sources effect, urea was proved to be the most effective and economic nitrogen source for xylanase production and used for further optimization.Finally, the CCD and response surface methodology (RSM) were applied to determine the optimal concentration of each sig-nificant variable, which included urea, Na2CO3 and MgSO4. Subsequently a second-order polynomial was determined by mul-tiple regression analysis. The optimum values of the critical components for maximum xylanase production were obtained as follows: x1 (urea)=0.163 (41.63 g/L), x2 (Na2CO3)=-1.68 (2.64 g/L), x3 (MGSO4)=1.338 (10.68 g/L) and the predicted xylanase value was 14374.6 U/g dry substrate. Using the optimized condition, xylanase production by Aspergillus niger XY-1 after 48 h fermentation reached 14637 U/g dry substrate with wheat bran in the shake flask. Conclusion: By using PBD and CCD, we obtained the optimal composition for xylanase production by Aspergillus niger XY-1 in SSF, and the results of no additional expensive medium and shortened fermentation time for higher xylanase production show the potential for industrial utilization. 相似文献
157.
Zhang XG Miao J Li MW Jiang SP Hu FQ Du YZ 《Journal of Zhejiang University. Science. B》2008,9(6):506-510
Herein, solid lipid nanoparticles (SLN) were proposed as a new drug delivery system for adefovir dipivoxil (ADV). The octadecylamine-fluorescein isothiocynate (ODA-FITC) was synthesized and used as a fluorescence maker to be incorporated into SLN to investigate the time-dependent cellular uptake of SLN by HepG2.2.15. The SLN of monostearin with ODA-FITC or ADV were prepared by solvent diffusion method in an aqueous system. About 15wt% drug entrapment efficiency (EE) and 3wt% drug loading (DL) could be reached in SLN loading ADV. Comparing with free ADV, the inhibitory effects of ADV loaded in SLN on hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg) and hepatitis B virus (HBV) DNA levels in vitro were significantly enhanced. 相似文献
158.
实验法是获得和巩固化学教学,发展学生智力、培养能力,调动学生积极性的重要手段.而实验法中的演示法是教师对直观教具进行"表演和展示",学生依靠感观来获得知识的方法.然而,从目前我们全面培养学生能力来看,教材上的有些演示实验的教学效果并不令人满意,我经过多年的摸索认为有很多地方可以改进. 相似文献
159.
Li SJ 《Isis; an international review devoted to the history of science and its cultural influences》2002,93(2):206-228
A distinct British approach to disease in the tropics has been identified in the recent historiography of colonial medicine: Mansonian tropical medicine, named after Sir Patrick Manson (1844-1922), the founder of the London School of Tropical Medicine. This essay examines Manson's study of filariasis (infection with the filarial nematode worm) and argues that his conceptual tools and research framework were derived from contemporary natural history. It investigates Manson's training in natural history at the University of Aberdeen, where some of his teachers were closely associated with transcendental biology. The concepts of perfect adaptation and the harmony of nature were crucial to the formulation of his research problematic. This essay demonstrates that biogeographical concepts played an important part in Manson's research methodology. It also investigates how Manson's natural historical approach contributed to the making of so-called Mansonian tropical medicine. 相似文献
160.
Resistin levels of serum and follicular fluid in non-obese patients with polycystic ovary syndrome during IVF cycles 总被引:1,自引:0,他引:1
Lu XE Huang HF Li MG Zhu YM Qiang YL Dong MY 《Journal of Zhejiang University. Science. B》2005,6(9):897-902
INTRODUCTION Polycystic ovary syndrome (PCOS) is a leading cause of anovulatory infertility and affects 5%~10% of reproductive age women (Dunaif, 1997). It is characterized by hyperandrogenemia and chronic anovulation and is associated with insulin resistance, obesity and increased risk for type 2 diabetes (Kno- chenhauer et al., 1998). Insulin resistance is thought to play an important role in aetiology of PCOS (Chang et al., 1983; Shoupe et al., 1983). In vitro and in vivo studies … 相似文献