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Influences on the bandwidth at the drop port of the add/drop filter using a fiber grating coupler by uniform and linearly chirped fiber Bragg grating

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Science China(Information Sciences) 2013年第6期56卷 39-44页

作者： FAN LinYong JIANG WeiWei ZHAO RuiFeng LI Jian PEI Li JIAN ShuiSheng institute of Lightwave Technology Beijing Jiaotong University signal & Communicaiton Research institute China Academy of Railway SciencesBeijing 100081China

Writing a fiber Bragg grating(FBG) in an optical fiber coupler is a very effective way to implement an optical add/drop filter(OADF).In order to analyze the influences on the bandwidth at the drop port of the OADF using fiber grating-assisted mismatched coupler,a uniform FBG and a linearly chirped FBG were written on the coupler,and two different OADFs were *** fiber grating is written in a 2×2 mismatched coupler,which is fused and tapered with a standard single mode fiber(SMF) and a high germanium doped photosensitive fiber,by using a 248 nm ultraviolet *** the OADF using the uniform FBG,the 3 dB and 20 dB bandwidths are 0.1 nm and 0.3 nm,respectively;for the OADF using the linear chirped FBG,the 3 dB and 20 dB bandwidths are 0.8 nm and 2 nm,*** experimental results meet the theoretical analysis *** bandwidth at the drop port of the device can be adjusted by adjusting the chirped coefficient of the linearly chirped FBG.

关键词： optical add/drop filter fiber Bragg grating coupler optical fiber communication

Prostate cancer： the need for biomarkers and new therapeutic targets

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第1期15卷 16-42页

作者： Juliana FELGUEIRAS Joana Vieira SILVA Margarida FARDILHA Laboratory of signal transduction Centre for Cell Biology Biology Department and Health Sciences Department University of Aveiro 3810-193 Aveiro Portugal

Prostate cancer （PCa） incidence and mortality have decreased in recent years. Nonetheless, it remains one of the most prevalent cancers in men, being a disquieting cause of men＇s death worldwide. Changes in many cell signaling pathways have a predominant role in the onset, development, and progression of the disease. These include prominent pathways involved in the growth, apoptosis, and angiogenesis of the normal prostate gland, such as an- drogen and estrogen signaling, and other growth factor signaling pathways. Understanding the foundations of PCa is leading to the discovery of key molecules that could be used to improve patient management. The ideal scenario would be to have a panel of molecules, preferably detectable in body fluids, that are specific and sensitive biomarkers for PCa In the early stages, androgen deprivation is the gold standard therapy. However, as the cancer progresses, it even- tually becomes independent of androgens, and hormonal therapy fails. For this reason, androgen-independent PCa is still a major therapeutic challenge. By disrupting specific protein interactions or manipulating the expression of some key molecules, it might be possible to regulate tumor growth and metastasis formation, avoiding the systemic side effects of current therapies. Clinical trials are already underway to assess the efficacy of molecules specially designed to target key proteins or protein interactions. In this review, we address that recent progress made towards under- standing PCa development and the molecular pathways underlying this pathology. We also discuss relevant molecular markers for the management of PCa and new therapeutic challenges.

关键词： Prostate cancer (PCa) Biomarker Androgen Estrogen Cell signaling pathway Therapeutical target

Detection time analysis for the multiple-user cooperative spectrum sensing scheme in cognitive radio networks

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Science in China(Series F) 2009年第10期52卷 1915-1925页

作者： ZHU Jia ZHENG BaoYu ZOU YuLong institute of signal Processing and Transmission Nanjing University of Posts and Telecomm Nanjing 210003 China

In this paper, a novel multiple-user cooperative spectrum sensing （MCSS） scheme is proposed to achieve the spatial diversity gains for cognitive radio （CR） networks, where only the best relay, selected among all the candidate relays in accordance with the quality of channel conditions, is utilized to cooperatively detect the primary user. Closed-form expressions of detection time for the traditional non-cooperative and the proposed MCSS schemes are derived over Rayleigh fading channels. In addition, numerical experimentations are conducted to make a performance comparison between the noncooperative sensing and our scheme. The result shows that by exploiting the multiple-user cooperation, the detection time is reduced greatly and moreover, diversity gains obtained by the MCSS scheme increase with a rise in the number of candidate relays.

关键词： cognitive radio networks multiple-user cooperation spectrum sensing cooperative diversity

Retroperitoneal disorders associated with Ig G4-related autoimmune pancreatitis

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World Journal of Gastroenterology 2014年第44期20卷 16550-16558页

作者： Noboru Hara Makoto Kawaguchi Keisuke Takeda Yoh Zen Division of Urology Department of Regenerative and Transplant Medicine Graduate School of Medical and Dental Sciences Niigata University Division of Molecular Oncology Department of Signal Transduction Research Graduate School of Medical and Dental Sciences Niigata University Division of Diagnostic Pathology Niigata Rousai Hospital institute of Liver Studies King’s College Hospital

Ig G4-related autoimmune pancreatitis is frequently accompanied by relevant lesions in the genitourinary tract and retroperitoneal organs, which cause various clinical problems, ranging from non-specific back pain or bladder outlet obstruction to renal failure. The diagnosis of Ig G4-related retroperitoneal fibrosis requires a multidisciplinary approach, including serological tests, histological examination, imaging analysis, and susceptibility to steroid therapy. Radiological examinations are helpful to diagnose this condition, but surgical resection is occasionally unavoidable to exclude malignancy, particularly for patients with isolated retroperitoneal involvement. Steroid therapy is the treatment of choice for this condition, the same as for other manifestationsof Ig G4-related *** patients with severe ureteral obstruction,additional ureteral stenting needs to be considered prior to steroid therapy to preserve the renal *** papers have suggested that Ig G4-related disease can affect male reproductive organs including the prostate and *** G4-related prostatitis usually causes lower urinary tract symptoms,such as dysuria and *** sometimes state that corticosteroids given for Ig G4-related disease at other sites relieve their lower urinary tract symptoms,which leads us to suspect prostatic involvement in this *** of the limited number of publications available,further studies are warranted to better characterize Ig G4-related disease in male reproductive organs.

关键词： IgG4 Autoimmune pancreatitis Retroperitoneum Genitourinary tract Management

Introduction of Foreign Genes into Silkworm Eggs by Electroporation and Its Application in Transgenic Vector Test

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 323-330页

作者： Xiu-Yang GUO#, Liang DONG#, Sheng-Peng WANG, Ting-Qing GUO, Jian-Yang WANG, and Chang-De LU* institute of biochemistry and Cell Biology, Shanghai institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China institute of biochemistry and Cell Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences

Electroporation as a methodology to introduce foreign genes into silkworm eggs was system- atically analyzed. The foreign gene in both the newly hatched and 3rd instar larva DNA can be detected by PCR. The amount of foreign gene in 3rd instar larva DNA was about 1/1000 of that in newly hatched larva DNA. The ratio of foreign gene entering into silkworm eggs was voltage dependent and showed significant difference between the tested silkworm strains. When the piggyBac transposon system was applied, the effect of nuclear localization signal (NLS) peptide and the in vitro transcribed transposase mRNA on the transposi- tion rate has been measured. Results showed that the in vitro transcribed transposase mRNA facilitated trans- position to take place earlier and NLS could result in higher transposition probability and earlier transposition as well. When linearized vectors containing varied length of flanking homologous sequences around a re- porter gene were introduced into silkworm eggs by electroporation, the one with 2.6 kb total arm length gave higher G1 positive ratio than that with total arm length of 1.5 kb and 800 bp.

关键词： silkworm eggs gene introduction electroporation transposon homologous sequences

Intestinal expressions of eNOSmRNA and iNOSmRNA in rats with acute liver failure

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World Journal of Gastroenterology 2001年第5期7卷 652-656页

作者： Jian-Min Qin~1 Yang-De Zhang~2 1 Department of Hepatobiliary & Enteric Surgery.Xiangya Hospital,Hunan Medical University,Changsha 410008,Hunan Province,China2 Department of Hepatobiliary & Enteric Surgery,Xiangya Hospital,Hunan Medical University,Changsha 410008,Hunan Province,China Biological signal transduction Center Eastern Hepatobiliary Surgery Hospital the Second Military Medical University Shanghai 200438 China. Jianminqin@***

AIM: To observe the gene expression change of eNOSmRNA and iNOSmRNA in the small and large intestines with acute liver failure (ALF), and to reveal the biological function of NO on the pathogenesis of ALF and multiple organs dysfunction at the molecular level. METHODS: Sixty male Wistar rats were selected, weighing from 250g to 350g, and divided into 5 groups randomly: SO, ALF (6h, 12h), L-Arg, L-NAME, L-Arg and L-NAME, each group with 10 rats. The dose of L-Arg was ***(-1), and L-NAME was ***(-1), the reagents diluted by normal saline were injected through tail vein 30 minutes pre and post operation. The rats in the ALF group were respectively sacrificed postoperatively at 6h, 12h, and the rats in the other groups were sacrificed postoperatively at 6h. The tissues of small and large intestines were harvested in 4% paraforaldehyde containing the reagent of DEPC and fixed at 6h, embedded in paraffin, and 4 microm section was cut. The expression of eNOSmRNA and iNOSmRNA in these tissues was determined with in situ hybridization, and analyzed with the imaging analysis system of CMM-3 and SPSS statistical software. RESULTS: The expression of eNOSmRNA in the large intestine and iNOSmRNA in the small and large intestines increased significantly at 6h after ALF, but the expression of iNOSmRNA in the small and large intestines reduced notably at 12h after ALF (P<0.05); the expression of eNOSmRNA in the large intestine and iNOSmRNA in the small and large intestines decreased significantly with the reagents of L-Arg at 6h ALF, but the expression of eNOSmRNA and iNOSmRNA in the small and large intestines decreased totally with the reagents of L-NAME or association with L-Arg 6h ALF. CONCLUSION: The expression of eNOSmRNA in the large intestine increased notably at the early stage of ALF, NO induced by the enzyme of eNOS from the transplantation of eNOSmRNA can protect the function of the large intestine, the high expression of iNOSmRNA is involved in the damaged fu

关键词： Acute Disease Animals Gene Expression Regulation, Enzymologic Intestines Liver Failure Male Nitric Oxide Synthase Nitric Oxide Synthase Type II Nitric Oxide Synthase Type III RNA, Messenger Rats Rats, Wistar

Study on MXR7 methylation in hepatocellular carcinoma

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Journal of Medical Colleges of PLA(China) 2005年第4期20卷 193-196页

作者：郭婷婷曾锦章王红阳 International Cooperation Laboratory on signal transduction Eastern Hepatobiliary Surgical Institute Secondary Military Medical University Shanghai 200433 China

Objective：To obtain information at the molecular level on the possible mechanism of MXR7 gene overexpressed in hepatocellular carcinoma （HCC） and also to provide a clue for further study. Methods：Genomic DNA was isolated from 20 samples of hepatoma and paired non-HCC liver tissues, 2 cases of blood tumor and two types of cells （HepG2, MCF-7） and digested with two kinds of endonucleases （EcoR I and Eag I which is methylation sensitive endonuclease）. And the condition of MXR7 gene methylation was examined and analyzed by Southern blot. Results： MXR7 was unmethylated neither in tested tumorous liver samples nor in paired non HCC liver tissues. In addition, the same result was found in 2 blood tumor samples and HepG2. Only two paired samples had different methylation outcome, one was unmethylated and the other was partly methylated. Conclusion： MXR7 is unmethylated in HHC, suggesting methylation of MXR7 may have no relation with its expression and regulation.

关键词： MXR7/GPC3 methylation hepatocellular carcinoma

Shp2-mediated molecular signaling in control of embryonic stem cell self-renewal and differentiation

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Cell Research 2007年第1期17卷 37-41页

作者： Gen-Sheng Feng~1 ~1Programs in signal transduction and Stem Cells and Regeneration,Burnham institute for Medical Research,10901 N.Torrey Pines Rd,La Jolla,CA 92037,USA Programs in signal transduction and Stem Cells and Regeneration Burnham Institute for Medical Research 10901 N. Torrey Pines Rd La Jolla CA 92037 USA. gfeng@***

A key issue to be addressed in stem cell biology is the molecular signaling mechanism controlling embryonic stem(ES) cell *** cell properties are dictated by specific transcription factors and epigenetic processes suchas DNA methylation and chromatin *** cytokines/growth factors have been identified as critical ES ***,there is a gap in our knowledge of the intracellular signaling pathways linking extracellular signalsto transcriptional regulation in ES *** short review discusses the physiological role of Shp2,a cytoplasmic tyro-sine phosphatase,in the molecular switch governing ES cell self-renewal versus ***2 promotes ES celldifferentiation,mainly through bi-directional modulation of Erk and Stat3 *** of Shp2 in mouse E S cellsresults in more efficient *** observation provides the impetus to develop Shp2 inhibitors for maintenanceand amplification of ES cells in culture.

关键词： Shp2 embryonic stem cell pluripotency embryonic stem cell self-renewal embryonic stem cell differentiation

Media-specific rate allocation in heterogeneous wireless networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 713-726页

作者： JURCA Dan FROSSARD Pascal Ecole Polytechnique Fédérale de Lausanne signal Processing institute Lausanne CH-1015 Switzerland

We address the problem of joint path selection and rate allocation in multipath wireless streaming, in order to optimize a media specific quality of service. We leverage on the existence of multiple parallel wireless services, in order to enhance the received video quality at a wireless client. An optimization problem is proposed, aimed at minimizing a video distortion metric based on sequence-dependent parameters, and transmission channel characteristics, for a given wireless network infrastructure. Even if joint optimal path selection and rate allocation is in general an NP complete problem, an in-depth analysis of the media distortion evolution allows defining a low complexity optimal streaming strategy, under reasonable network assumptions. In particular, we show that a greedy allocation of rates along paths with increasing error probability leads to an optimal solution. We argue that a network path should not be chosen for transmission, unless all other available paths with lower error probability have been chosen. Moreover, the chosen paths should be used at their maximum end-to-end bandwidth. These results are demonstrated for both independent network paths, and non-disjoint channel segments, in generic network topologies. Simulation results showed that the optimal rate allocation carefully trades off total encoding/transmission rate, with the end-to-end transmission error probability and the number of chosen paths. In many cases, the optimal rate allocation provides more than 20% improvement in received video quality, compared to heuristic-based algorithms.

关键词： Multipath streaming, Path selection, Rate allocation, Video streaming