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Mechanisms of secondary damage to the thalamic nucleus and substantia nigra in an adult hypertensive rat model following middle cerebral artery occlusion

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Neural Regeneration Research 2010年第11期5卷 853-858页

作者： Li Xiong Jian Yu Songjie Liao Shihui xing zhan Zhao Jinsheng Zeng Stroke Center and Department of Neurology First Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 Guangdong ProvinceChina

BACKGROUND： Following ischemia, apoptosis is observed at the ipsilateral ventropostenor thalamic nucleus and substantia nigra, which are distant from, but connected to, the ischemic cerebral cortex, in animals with normotension. However, secondary brain damage in hypertension has not been clearly investigated. OBJECTIVE： The present study determined whether neuronal apoptosis is associated with neuronal loss in the ipsilateral ventroposterior thalamic nucleus and substantia nigra following cortical ischemia in adult hypertensive rats. Results should provide options for determining a time window for anti-apoptotic therapy. DESIGN, TIME AND SETTING： All experimental procedures in this randomized, controlled trial were conducted at the Neurological Laboratory of the First Affiliated Hospital of Sun Yat-sen University of China between October 2006 and July 2008. MATERIALS： Monoclonal primary antibodies specific to mouse anti-rat microtubule-associated protein 2 and glial fibrillary acidic protein were respectively purchased from Sigma Chemical, USA and BD Pharmingen, USA. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling （TUNEL） detection kits were purchased from Roche Applied Science, Switzerland and Upstate, USA, respectively. METHODS： A total of 64 male, Sprague Dawiey rats, aged 60-90 days, were equally and randomly divided into middle cerebral artery occlusion and sham surgery groups. Renovascular hypertension was established in both groups by renal artery occlusion. Right distal middle cerebral artery occlusion was performed by electrocoagulation in the middle cerebral artery occlusion group. MAIN OUTCOME MEASURES： Microtubule-associated protein 2 and glial fibrillary acidic protein were detected by immunohistochemistry, and apoptotic cells were observed by TUNEL assay. The stainings were separately detected in the ipsilateral ventroposterior thalamic nucleus and substantia nigra. RESULTS： During the 4 weeks followin

关键词： ventroposterior thalamic nucleus substantia nigra apoptosis rats cerebral infarction neural regeneration

Hybrid analytical resolution approach based on ambiguity function for attitude determination

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第7期10卷 1038-1048页

作者： Wen-rui JIN Chuan-run ZHAI Li-duan WANG Yan-hua zhanG xing-qun zhan Institute of Aerospace Science & Technology Shanghai Jiao Tong University Shanghai 200240 China

When satellite navigation receivers are equipped with multiple antennas, they can deliver attitude information. In previous researches, carrier phase differencing measurement equations were built in the earth-centered, earth-fixed (ECEF) co- ordinate, and attitude angles could be obtained through the rotation matrix between the body frame (BF) and the local level frame (LLF). Different from the conventional methods, a hybrid algorithm is presented to resolve attitude parameters utilizing the single differencing (SD) carrier phase equations established in LLF. Assuming that the cycle integer ambiguity is known, the measure- ment equations have attitude analytical resolutions by using simultaneous single difference equations for two in-view satellites. In addition, the algorithm is capable of reducing the search integer space into countable 2D discrete points and the ambiguity function method (AFM) resolves the ambiguity function within the analytical solutions space. In the case of frequency division multiple access (FDMA) for the Russian Global Orbiting Navigation Satellite System (GLONASS), a receiver clock bias estimation is employed to evaluate its carrier phase. An evaluating variable and a weighted factor are introduced to assess the integer ambiguity initialization. By static and dynamic ground experiments, the results show that the proposed approach is effective, with enough accuracy and low computation. It can satisfy attitude determination in cases of GPS alone and combined with GLONASS.

关键词： Global positioning system (GPS) Russian Global Orbiting Navigation Satellite System (GLONASS) Analytical resolution Attitude determination Ambiguity function method (AFM)

Recent progress in hair follicle stem cell markers and their regulatory roles

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World Journal of Stem Cells 2024年第2期16卷 126-136页

作者： Yi-zhan xing Hai-Ying Guo Fei Xiang Yu-Hong Li Department of Cell Biology Army Medical UniversityChongqing 400038China Institute of Burn Research Southwest HospitalArmy Medical UniversityChongqing 400038China

Hair follicle stem cells(HFSCs)in the bulge are a multipotent adult stem cell *** can periodically give rise to new HFs and even regenerate the epidermis and sebaceous glands during wound *** increasing number of biomarkers have been used to isolate,label,and trace HFSCs in recent *** more detailed data from single-cell transcriptomics technology,we mainly focus on the important HFSC molecular markers and their regulatory roles in this review.

关键词： Hair follicle stem cells Bulge Secondary hair germ Marker Single-cell RNA-sequencing

Large delay tunable slow-light based on high-gain stimulated-Brillouin-scattering amplification in optical fibers

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Chinese Science Bulletin 2009年第15期54卷 3947-3952页

作者： xing Liang zhan Li XIA Yuxing Department of Physics State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao TongUniversity Shanghai 200240 China

Tunable stimulated-Brillouin-scattering (SBS)-based slow-light in optical fibers has potential applications in optical buffering in the future all-optical router commutation systems. However, due to the low SBS threshold and relatively high realistic signal power, the gain in the usual SBS systems is limited at^30 dB. This paper presents a high-gain SBS scheme to realize large delay slow-light, which benefits from avoiding the depletion of the pump power in a short fiber as SBS media. The experiment demonstrates that, up to 50 dB non-saturated gain has been observed in the single-stage 591.8 m fiber SBS amplification. The slow-light delay can be obtained 52 ns, and the fractional delay can exceed 1.

关键词：布里渊散射增益放大延迟光纤可调整流系统全光路由器信号功率

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S-phase arrest after vincristine treatment may promote hepatitis B virus replication

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World Journal of Gastroenterology 2015年第5期21卷 1498-1509页

作者： Lei Xu Zeng Tu Ge Xu Jie-Li Hu Xue-Fei Cai xing-xing zhan Yu-Wei Wang Yuan Huang Juan Chen Ai-Long Huang Key Laboratory of Molecular Biology on Infectious Diseases Ministry of EducationChongqing Medical University Department of Microbiology Chongqing Medical University Department of Pediatrics Chongqing Medical University

AIM:To observe the effect of vincristine on hepatitis B virus(HBV) replication in vitro and to study its possible ***:Vincristine was added to the cultures of two cell lines stably expressing ***,the levels of hepatitis B surface antigen(HBs Ag),hepatitis B e antigen(HBe Ag),and hepatitis B core antigen(HBc Ag) in the supernatants or cytoplasm were examined using by enzyme-linked immunosorbent assay and Western *** HBV pregenome RNA(pg RNA) was detected using reverse transcription-PCR and realtime fluorescent quantitative PCR(RT-q PCR),and viral DNA was detected using Southern blot and RT-q *** proliferation after drug treatment was detected using the Brd U incorporation test and the trypan blue exclusion *** cycle and cell apoptosis were examined using flow cytometry and Western ***:Vincristine up-regulated HBV replication directly in vitro in a dose-dependent manner,and 24-h exposure to 0.1 μmol/L vincristine induced more than 4-fold and 3-fold increases in intracellular HBV DNA and the secretion of viral DNA,*** expression of HBV pg RNA,intracellular HBs Ag and HBc Ag,and the secretion of HBe Ag were also increased significantly after drug *** importantly,vincristine promoted the cell excretion of HBV nucleocapsids instead of HBV Dane particles,and the nucleocapsids are closely related to the HBV ***,vincristine inhibited the proliferation of cells stably expressing *** higher the concentration of the drug,the more significant the inhibition of the cell proliferation and the stronger the HBV replication ability in *** cytometry indicated that cell cycle arrest at S-phase was responsible for the cell proliferation ***:Vincristine has a strong stimulatory effect on HBV replication and induces cell cycle arrest,and cell proliferation inhibition may be conducive to viral replication.

关键词： Viral reactivation Cytotoxic chemotherapy Cell cyc

Five quinolizidine alkaloids with anti-tobacco mosaic virus activities from two species of Sophora

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Chinese Chemical Letters 2024年第6期35卷 380-384页

作者： Ji zhang Tong zhang Qiao An Peng zhang Cai-Yan Tian Chun-Mao Yuan Ping Yi zhan-xing Hu Xiao-Jiang Hao State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China Natural Products Research Center of Guizhou Province Guiyang 550014China School of Pharmaceutical Sciences Guizhou Medical UniversityGuiyang 550025China School of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming 650201China Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical SciencesKunming 650201China

Three novel matrine-type alkaloids(1-3)and two unprecedented aloperine-type alkaloids(4 and 5)were isolated from the root of Sophora tonkinensis and the seeds of Sophora alopecuroides ***,compound 1 possessed an unprecedented 6/5/6 tricyclic skeleton,while compounds 2 and 3 characterized by rare 6/6/5/6 tetracyclic system and 6/6/6/6/6 pentacyclic system ***,compound 4 possessed an unprecedented 6/7/6/6 tetracyclic core,and compound 5 characterized by rare 6/6/6/6tetracyclic *** structures were elucidated by comprehensive spectroscopic data analysis and electronic circular dichroism(ECD)*** tests indicated that compound 5 displayed significant anti-tobacco mosaic virus(TMV)activity compared with the positive control ningnanmycin.

关键词： Matrine-type alkaloids Aloperine-type alkaloids Sophora tonkinensis Sophora alopecuroides Anti-tobacco mosaic virus

Research on phase-detecting method for coherent combining beams in fiber laser array

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Optoelectronics Letters 2007年第6期3卷 455-458页

作者： CHU xing-chun zhan Sheng-bao ZHAO Shang-hong LI Yun-xia XU Jie Department of Network Engineering Telecommunication Engineering Institute Air Force Engineering University Xi＇ an710077 China

A novel method for phase-detecting of each individual beam in coherent beam combining system of fiber laser array based on the property of time-shift of fast Fourier transform is reported. It takes advantage of the relative movement of fringepattern to detect the phase shift between each individual beam and reference beam. No frequency shift component for reference beam is required in the system. At the same time, the acquisition fringe-pattern is firstly tailored to a few multiple of fringes in order to reduce the phase-detecting error caused by energy leakage during the course of fast Fourier transform. This technique can greatly reduce the effect of energy leakage and thus improve the phase-detecting precision. Basic principle of the new phase-detecting method is described in detail, and numerical results show that the phase-detecting error is less than 1/1000 wavelength bv utilizing our method.

关键词：光检测技术光纤元件组合光束激光

Resistance fluctuations in superconducting K_(x)Fe_(2-y)Se_(2) single crystals studied by low-frequency noise spectroscopy

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Chinese Physics B 2021年第4期30卷 502-507页

作者： Hai Zi Yuan Yao Ming-Chong He Di Ke Hong-xing zhan Yu-Qing Zhao Hai-Hu Wen Cong Re Physics Department School of Physics and AstronomyYunnan UniversityKunming 50500China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of ScienceBeijing 100190China Physics Department Nanjing UniversityNanjing 210093China

Low-frequency resistance noise spectroscopy is applied to investigate bulk single crystals of the intercalated ironselenide K_(x)Fe_(2-y)Se_(2) superconductors with different iron vacancy *** on a generalized fluctuation model,the well-observed resistance hump above 100 K is interpreted as an insulator-metal phase transition with a characteristic transition energy of 0.1-0.6 eV,indicating a highly inhomogeneous energy distribution *** the superconducting transition regime,we find that the normalized resistance noise scales with resistance R excellently as S_(R)/R^(2)∝R^(l_(rs)) with the noise exponent lrs≈*** reduced iron vacancy disordering in enhanced superconductivity K_(x)Fe_(2-y)Se_(2) crystals,the level of resistance fluctuations is greatly suppressed,suggesting a geometrical phase transition for conduction channel,which is directly related to the microstructure of the crystals.

关键词： K_(x)Fe_(2-y)Se_(2) phase separation noise and chaos percolation

Hypermonones A-I,New Polyprenylated Acylphloroglucinols from Hypericum monogynum with Multidrug Resistance Reversal Activity

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Chinese Journal of Chemistry 2021年第9期39卷 2422-2432页

作者： Yan-Rong Zeng Ya-Nan Li Jue Yang Ping Yi Lei Huang Lie-Jun Huang Wei Gu zhan-xing Hu Yan-Mei Li Chun-Mao Yuan Xiao-Jiang Hao State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyangGuizhou 550014China The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences GuiyangGuizhou 550014China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China

Eleven biogenetically related polyprenylated acylphloroglucinols(PPAPs),including four novel skeletons(1-4)and five new com-pounds(5-9),were isolated from the flowers of Hypericum *** A-D(1-4)represented the first example of a unique dilactone structure containing carbonyl bonded single 5-lactone and tricyclic γ-lactone *** structures were elucidated by NMR analysis,X-ray crystallography,and ECD ***,we revised the structure of hyperibrin B to hy perm on one I(9)via NMR an alysis,a qua ntum computational chemistry method,and hypothetic bios yn thetic con *** compounds(5,6,and 9)with significant MDR reversal activity(RF ranging from 61 to 223)were superior to the positive control verapamil(MCF-7/ADR,RF:53;HepG2/ADRz RF:124).Mechanism study for compound 5 indicated that this compound could inhibit the function of P-gp tran sport rather tha n its expressi on,and the possible recog nition mechanism betwee n compo und 5 and P-gp was predicted by molecular docking.

关键词： Hypericum monogynum Phytochemistry Structure elucidation Biological activity Multidrug resistance reversal activity