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Chinese Science Bulletin 2007年第8期52卷 1029-1035页

作者： feng juan li Xuefeng liU Yuan School of life Science and Technology University of Electronic Science & Technology of China Chengdu 610054 China

Steady-state absorption spectroscopy,circular dichroism,and resonance Raman spectroscopy have been used to investigate the thermal stability of LH2 complex isolated from purple photosynthetic bacterium *** results show that:1)upon increasing the temperature,a transition from B800 and B850 to free bacteriochlorophyll(B780)happens;2)a gradual decrease and disappearance of CD signal in visible region occur;3)a shift of the frequency,belonging to C==C and C—C stretching vibration,to higher wavenumber takes *** is suggested that LH2 complex can be dissociated in the presence of B800,B850 and carotenoids ***-exponential fitting on the dynamic decay curves gives the apparent time constants of hundreds of minutes for various pigments.

关键词：紫色光合细菌沼泽红假单胞菌温度诱导离解反应反应动力学捕光配合物Ⅱ

Degradation of a fullerene end-capped polycaprolactone by lipase AK

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Chinese Science Bulletin 2010年第29期55卷 3279-3282页

作者： PENG QiYun KANG feng li juan YANG Xinlin School of life Science and Technology Beijing Institute of Technology Beijing 100081 China

Using titrimetric method,enzymatic behavior of lipase AK against fullerene end-capped polycaprolactone(C60-PCL) was studied for the first time,compared with polycaprolactone(PCL).The results showed that degradation of both C60-PCL and PCL by lipase followed Mechaelis-Menten equation,with the degradation parameters of PCL and C60-PCL were 0.75 mg mL-1 and 0.16 mg mL-1 for Km,and 0.90 mL h-1 and 0.43 mL h-1 for Vmax,respectively.C60-PCL had a slower degradation rate than PCL under the same *** data indicated that the introduction of fullerene enabled PCL hard to be degraded by lipase.

关键词：聚己内酯脂肪酶富勒烯降解酶封端 PCL C60 米氏方程

Design and performance analysis of wireless sensor network location node system for underground mine

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Mining Science and Technology 2009年第6期19卷 813-818页

作者： CHEN Guang-zhu SHEN Chun-feng ZHOU li-juan School of Mechanical ＆ Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Aiming at the application of a wireless sensor network to locating miners in underground mine,we design a wireless sensor network location node system,considering the communication performance and the intrinsic safety. The location node system consists of a mobile node,several fixed nodes,and a sink node,all of whose circuits were designed based on CC2430. A varistor and a RC circuit were used in the reset circuit of a sensor node to guarantee the intrinsic safety by reducing discharge energy,the theoretical analysis of the discharge energy shows that the reset circuit is an intrinsic safety one. The analysis and simulation about the performance of the location node system are discussed,such as network communication delay and packet loss rate,the results show that the highest network communication delay of the system is about 0.11 seconds,and the highest packet loss rate is about 0.13,which assures the location node system has a high reliability,and can locate miners in the underground mine.

关键词： wireless sensor network location node network communication delay packet loss rate

Role of DJ-1-induced PTEN down-regulation in migration and invasion of human glioma cells

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Chinese Journal of Cancer 2010年第12期29卷 988-994页

作者： Mao Fang Xue-Yun Zhong Bin Du Chen-li lin feng Luo li-juan Tang juan Chen Department of Pathology Medical College Jinan University Guangzhou Guangdong 510632 P. IR. China

Background and Objective: DJ-1, a suppressor of PTEN, promotes metastasis of different tumors, but its function and mechanisms in glioma metastasis remain unclear. This study aimed to investigate the effect of the DJ-1 protein on the migration and invasion of human glioma cells, and to explore potential mechanisms. Methods: The eukaryotic expression vector pEGFP/DJ-1 and small interfering RNA (siRNA) were constructed and transfected into human glioma SWO-38 cells. The expression of DJ-1 and PTEN in SWO-38 cells were detected by Western blot. Cell migration and invasion were detected by transwell assay. Results: After transfection of pEGFP/DJ-1, the expression of DJ-1 (1.28 ± 0.15 vs. 0.89 ± 0.04, P < 0.05) and focal adhesion kinase (FAK) phosphorylation (0.76 ± 0.12 vs. 0.51 ± 0.04, P < 0.05) were increased, whereas the expression of PTEN (0.74 ± 0.2 vs. 1.04 ± 0.14, P < 0.05) was suppressed. After transfection of DJ-1 siRNA, both DJ-1 (0.33 ± 0.04 vs. 0.88 ± 0.06, P < 0.05) and p-FAK levels (0.33 ± 0.01 vs. 0.44 ± 0.05, P < 0.05) were decreased, but PTEN expression (1.1 ± 0.06 vs. 0.81 ± 0.12, P < 0.05) was increased. Transwell assay data showed that pEGFP/DJ-1 transfection promoted SWO-38 cell migration (57.2 ± 6.50 vs. 40.4 ± 5.0, P < 0.05) and invasion (54.6 ± 4.9 vs. 27 ± 6.7, P < 0.05), whereas DJ-1 siRNA transfection inhibited SWO-38 cells migration (54.4 ± 6.9 vs. 73.4 ± 7.6, P < 0.05) and invasion (44.6 ± 5.8 vs. 69.2 ± 9.2, P < 0.05). Conclusion: Over-expression of DJ-1 promotes SWO-38 cell migration and invasion possibly through the DJ-1 and the PTEN/FAK pathway.

关键词： PTEN基因胶质瘤细胞细胞迁移侵袭人脑社会工作细胞转染入侵检测

Pleurotus nebrodensis polysaccharide(PN-S) enhances the immunity of immunosuppressed mice

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Chinese Journal of Natural Medicines 2015年第10期13卷 760-766页

作者： CUI Hai-Yan WANG Chang-Lu WANG Yu-Rong li Zhen-Jing CHEN Mian-Hua li feng-juan SUN Yan-Ping Key Laboratory of Food Nutrition and Safety Ministry of Education School of Food Engineering and Biotechnology Tianjin University of Science and Technology

In the present study, the effects of Pleurotus nebrodensis polysaccharide(PN-S) on the immune functions of immunosuppressed mice were determined. The immunosuppressed mouse model was established by treating the mice with cyclophosphamide(40 mg/kg/2d, CY) through intraperitoneal injection. The results showed that PN-S administration significantly reversed the CY-induced weight loss, increased the thymic and splenic indices, and promoted proliferation of T lymphocyte, B lymphocyte, and macrophages. PN-S also enhanced the activity of natural killer cells and increased the immunoglobulin M(Ig M) and immunoglobulin G(Ig G) levels in the serum. In addition, PN-S treatment significantly increased the phagocytic activity of mouse peritoneal macrophages. PN-S also increased the levels of interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), interferon-γ(INF-γ), and nitric oxide(NOS) in splenocytes. q RT-PCR results also indicated that PN-S increased the m RNA expression of IL-6, TNF-α, INF-γ, and nitric oxide synthase(i NOS) in the splenocytes. These results suggest that PN-S treatment enhances the immune function of immunosuppressed mice. This study may provide a basis for the application of this fungus in adjacent immunopotentiating therapy against cancer and in the treatment of chemotherapy-induced immunosuppression.

关键词： Immunosuppressed mice Pleurotus nebrodensis polysaccharide Cyclophosphamide

A review and comparison of common maternal positions during the second-stage of labor

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International Journal of Nursing Sciences 2019年第4期6卷 460-467页

作者： Jing Huang Yu Zang li-Hua Ren feng-juan li Hong Lu School of Nursing Peking University Beijing China Maternal and Child Health Hospital of Xinjiang Uyghur Autonomous Region Uyghur China

The second-stage of labor is the most stressful part of childbirth process and the proper maternal position during this period is paramount for women's safe vaginal *** play a pivotal role in managing maternal positions during the second-stage of ***,there is limited evidence to support an ideal maternal position during the second-stage of ***,the difference between different maternal positions might not be *** paper aims to review and compare the benefits and risks of common maternal positions during the second-stage of labor,thereby to provide midwives evidence-based practical guidelines.

关键词： Second labor stage Parturition Posture Review

Pillared-layer MOF Based on Template-directed Method: Synthesis, Structure and Proton Conduction Properties

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1337-1342页

作者： WANG Fu-Xiang REN Guo-Jian TIAN Rui-Jing feng li-juan YANG Yong-Hang DENG Yong-Yan PAN Qin-He Key Laboratory of Advanced Materials of Tropical Island Resources Ministry of EducationSchool of ScienceHainan UniversityHaikou 570228China School of Information Engineering Changchun Sci-Tech UniversityChangchun 130600China

By using Co(NH3)63+as the template,a new complex HNU-38 was synthesized under hydrothermal reaction through the adoption of H3BTC and Cl-as the ligands(H3BTC=1,3,5-benzenetricarboxylic acid).HNU-38 crystallized in the monoclinic system,P21/c space group with a=9.9696(3),b=17.0580(6),c=16.5263(6)?,β=100.400(2)o,Z=4,V=2764.31(16)?3,Mr=883.63,Dc=2.123 g/cm3,F(000)=1736,S=0.920,R=0.0358 and wR=0.0838(Ⅰ>2σ(Ⅰ)).In HNU-38,the Cd2+and BTC3-were linked together to form layers with Cl-serving as the *** should be noted that(H2O)n chains were found in the channels and play a co-templating role along with the Co(NH3)63+cations in HNU-38,and the proton conduction properties were investigated.

关键词： template synthesis metal-organic framework pillared-layer proton conduction

Effects of pH on the peripheral light-harvesting antenna complex for Rhodopseudomonas palustris

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Science China(life Sciences) 2008年第8期51卷 760-766页

作者： feng juan, li Xuefeng & liU Yan School of life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China School of life Science and Technology University of Electronic Science and Technology of China Chengdu China

In this work steady-state absorption spectroscopy, circular dichroism spectroscopy and sub-micro-second time-resolved absorption spectroscopy were used to investigate the effect of pH on the struc-tures and functions of LH2 complex for Rhodopseudomonas palustris. The results revealed that: (1) B800 Bchla was gradually transformed to free pigments absorbing around 760 nm on the minutes timescale upon the induction of strong acidic pH, and subsequently there disappeared the CD signal for Qy band of B800 in the absence of B800. In addition, Carotenoids changed with the similar tendency to B850 BChl. (2) The introduction of strong basic pH gave rise to no significant changes for B800 Bchla, while B850 BChla experienced remarkable spectral blue-shift from 852 to 837 nm. Similar phe-nomenon was seen for the CD signal for Qy band of B850. Carotenoids displayed strong and pH-independent CD signals in the visible range. (3) In the case of both physiological and basic pH, broad and asymmetrical positive Tn←T1 transient absorption appeared following the pulsed photo-excitation of Car at 532 nm. By contrast, the featureless and weak positive signal was observed on the sub-microsecond timescale in the acidic pH environment. The aforementioned experimental results indicated that acidic pH-induced removal of B800 Bchla prevented the generation of the caro-tenoid triplet state (3Car*), which is known to be essential for the photo-protection function. Neverthe-less, carotenoids can still perform this important physiological role under the basic pH condition, where the spectral blue shift of B850 exerts little effect on the overall structure of the cyclic aggregate, therefore favoring the formation of carotenoid triplet state.

关键词： pH-induced B800-removal triplet state photo-protection function

Effect of antiallergic herbal agents on chloride channel-3 and immune microenvironment in nasal mucosal epithelia of allergic rhinitis rabbits

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Chinese Medical Journal 2010年第8期123卷 1034-1038页

作者： WANG li-feng XU li-juan GUO feng-hua WANG li-na SHEN Xiao-hong Medical College of Nankai University Tianjin 300071 China

Background Allergic rhinitis （AR） is a Th2 dominant cytokine response. Chloride channel-3 （CIC-3） plays an important role in nasal mucosal edema and inflammatory pathologic changes in AR. Antiallergic herbal agents （AHA） are antiallergic herbal products. In the previous study, we have demonstrated that AHA clearly inhibited allergic medium and relieved allergic reaction of AR. The aim of this study was to evaluate the function of CIC-3 and discuss the possible therapeutic effects of AHA on immune microenvironment in AR. Methods AHA were produced and used to treat AR. An animal model of an AR rabbit was established by ovalbumin （OVA）. The rhinitis rabbits were randomly divided into three groups： AHA treated group （AHATG）, model group （MG） and healthy control group （HCG）. The expressions of CIC-3 protein were examined by immunohistochemical method. The mucosal epithelial cells of all the rabbit groups were primarily cultured with tissue culture method in vitro with or without rhlL-4 or rhlL-2. Furthermore, the expressions of CIC-3 mRNA were detected by real-time PCR. The levels of monocyte chemotactic factor-1 （MCP-1） and vascular cell adhesion molecule-1 （VCAM-1） protein in culture supernatants were measured by EliSA. Results The expressions of CIC-3 mRNA increased more in mucosal epithelial cells of MG than those in AHATG and HCG （P 〈0.01）. The levels of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of MG were significantly higher than those in the other two groups （P 〈0.01）. Those were significantly increased in MG untreated 12 hours later than those in other two groups （P 〈0.01）. The expressions of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of MG and HCG treated with rhlL-4 were significantly higher than those in the AHATG treated with rhlL-4 （P 〈0.01）. The levels of CIC-3 mRNA, MCP-1 and VCAM-1 protein in culture supernatants of all groups treated with rhlL-2 showed no significant changes （P 〉0.05）. Conclusions AHA can inhibit the

关键词： chloride channel-3 antiallergic herbal agents allergic rhinitis immune microenvironment

香榧酯分子及晶体结构、热力学和电子性质的理论研究

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原子与分子物理学报 2025年第2期42卷 49-56页

作者：杜洪臣郇伟伟潘荣凯李洁刘彬李梦忍马湛冯丽娟刘军孟令成刘海舰邢仁卫董希青孙超李春霞王恒全潍坊科技学院山东省海洋精细化工绿色化高值化工程技术研究中心潍坊262700 浙江农林大学化学与材料工程学院浙江省林业生物质化学利用重点实验室杭州311300

香榧子假种皮中含有丰富的活性物质,挥发油、萜类、黄酮类等物质.香榧酯作为一种二萜类物质,具有抗氧化活性、抗病毒作用.本文采用量子化学计算方法对香榧酯的分子及晶体结构进行研究,得到其微观结构参数、红外光谱、晶胞参数.根据统计... 详细信息

香榧子假种皮中含有丰富的活性物质,挥发油、萜类、黄酮类等物质.香榧酯作为一种二萜类物质,具有抗氧化活性、抗病毒作用.本文采用量子化学计算方法对香榧酯的分子及晶体结构进行研究,得到其微观结构参数、红外光谱、晶胞参数.根据统计热力学原理,计算了标题物的标准热力学函数,包括摩尔热容(C_(p,m)^(o))、摩尔熵(S_(m)^(o))和摩尔焓(H_(m)^(o)).在DFT优化分子结构的基础上,采用力场方法得到香榧酯的最可能堆积方式属于P21空间群,进一步采用DFT GGA-RPBE方法优化其晶体结构,并计算能带结构和态密度,发现其带隙较宽(3.324 eV),表明其具有较好的稳定性.在Fermi能级附近,香榧酯晶体中的导带主要来自于O原子和C原子的2p轨道的贡献,而价带主要来自于H原子的s轨道.

关键词：香榧酯分子结构晶体结构理论研究