检索结果-南通市图书馆

A New Route for the Synthesis of N-Substituted Diketopiperazine Derivatives

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第4期17卷 469-472页

作者： Xi GONG xiao xiao yang De Xin WANG Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050

Eight N-substituted diketopiperazines （DKPs） were synthesized by solid-phase protocols. The introduction of iminodiacetic acid （Ida） and followed another a-amino acid residue as the precursor of DKP framework made... 详细信息

关键词： Diketopiperazine iminodiacetic acid solid-phase synthesis.

A facile synthesis of imino-protected cyclic guanidine derivatives from diamines

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第12期22卷 1399-1402页

作者： Jian Hai Yuan xiao xiao yang Hao Lin De Xin Wang Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

A convenient one-step synthesis of five-membered or six-membered imino-protected cyclic guanidine via an intramolecular ring-closure reaction of alkyl diamine（2a-2g） with 1,3-diamino-protected methylisothiourea（1a and 1b） was established and *** guanidine such as 3-（2-aminoethyl）-1,2-dibenzyloxycarbonylguanidine（4a） has been proved to be the intermediate of the reaction via utilizing mono-protected diamine as starting *** intramolecular ring closure of 4a results in 2-benzyloxycarbonyliminoimidazolidine（3a）.This new one-step synthesis has advantages of simple condition,easy workup procedure and reasonable yield.

关键词： Intramolecular cyclization 1 4-Nucleophilic addition Alkyldiamines Cyclic guanidine

A novel peptide from Apis mellifera and solid-phase synthesis of its analogue

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2012年第10期23卷 1161-1164页

作者： Yu Meng xiao xiao yang Yu Xin Sheng Jin Lan Zhang De Quan Yu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Peking Union Medical CollegeInstitute of Materia MedicaChinese Academy of Medical SciencesBeijing 100050China

A novel peptide designated secapin-1, was purified and characterized from Apis mellifera. The molecular weight of 25 amino acid peptide secapin-1 was found to be 2821.5625 Da by ESI-FTICR-MS. It showed high identity to secapin. The sequence of secapin-1 was determined to be YIINVPPRCPPGSKFVKNKCRVIVP by automatic Edman degradation. A disulfide bond was formed between Cys9 and Cys20 residues. In addition, an analogue of secapin-1 was synthesized by solid phase peptide synthesis method. The synthesis product was successfully purified and identified to homogeneity by using a combination of SEC, IEC, and RP-HPLC techniques.

关键词： Bee venom Peptide Amino acid sequence

Tumor inflammation-specific self-amplifying fluorescent molecular probes induce an anti-tumor immune response

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期68卷 273-287页

作者： Shuguang yang Lijun Hu Hong xiao Zecong xiao Xintao Shuai PCFM Lab of Ministry of Education School of Materials Science and Engineering Sun Yat-sen University Department of Ultrasound The Fifth Affiliated Hospital Sun Yat-sen University Department of Medical Ultrasound The Third Affiliated Hospital of Sun Yat-sen University Nanomedicine Research Center The Third Affiliated Hospital of Sun Yat-sen University

Enhancing the concentration of exogenous molecular drugs within the tumor microenvironment through enzyme-catalyzed polymerization presents a novel strategy for cancer therapy. Nonetheless, the optimization of the catalytic efficiency is often impeded by the inefficient expression of enzymes. Herein, we reported a self-amplifying fluorescent molecular probe, Bis-HTPICG, for photodynamic therapy(PDT) and subsequent PDT-induced immunoreaction. The Bis-HTP-ICG probe possesses a noticeable enzyme-catalyzed polymerization facilitated by myeloperoxidase(MPO), a crucial enzyme secreted by neutrophils at inflammation sites. Upon exposure to laser irradiation, Bis-HTP-ICG showed a high PDT efficacy, inducing an acute inflammatory response that stimulates further recruitment of neutrophils and then elevated MPO secretion. The heightened level of MPO enhances the accumulation of the Bis-HTP-ICG via self-polymerization or binding with intratumoral proteins following MPO enzyme catalysis, instigating a self-amplifying chain reaction cycle involving Bis-HTP-ICG, neutrophils and ***, PDT efficiently incites immunogenic cell death(ICD) in tumor cells, initiating an anti-tumor immune response including dendritic cells(DCs) maturation, T cell proliferation and reprogramming of tumor-associated neutrophils(TANs). This work portrays a promising strategy for self-amplification of fluorescent molecular probes through adjustable enzyme levels,potentially offering a unique avenue to enhance the tumor accumulation of molecular drugs for improved tumor therapy.

关键词： fluorescent molecular probes self-amplifying myeloperoxidase photodynamic therapy

Passive harmonic mode locked Yb-doped fibre all-normal-dispersion lasers

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2011年第2期20卷 266-270页

作者： Kong Ling-Jie xiao xiao-Sheng yang Chang-Xi State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instruments Tsinghua University Beijing 100084 China

Passive harmonic mode-locking of dissipative solitons is demonstrated in all-normal dispersion Yb-doped fibre lasers. A difference equation model of the mode-locked fibre lasers is adopted to simulate the intra-cavity nonlinear dynamics. Hysteresis phenomena around the mode-locking threshold, and the effect of introducing linear phase bias are discussed. The passive harmonic mode-locking as one kind of multipulsing operations is revealed. Moreover, the simulation shows the bistability between multipulsing and single-pulse or period multiplication.

关键词： fibre laser mode-locking ytterbium

Forkhead box protein 3 mRNA expression in the peripheral blood of kidney-transplant recipients with acute rejection

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Medical Journal 2011年第12期124卷 1775-1778页

作者： WANG Wei LI xiao-bei yang xiao-yong ZHANG xiao-dong Department of Urology Beijing Chaoyang Hospital CapitalMedical University Beijing 100020 China

Background Regulatory T cells （Tregs） are immunologically and clinically interesting not least because of the important role they play in allograft rejection. Likewise, expression of the transcription factor forkhead box protein 3 （FOXP3）, detected in transplant biopsies, is also of intere.（;t because of its role in the development of regulatory T cells. In this study, we investigated the relationship between FoxP3 mRNA expression and acute organ rejection in kidney-transplant recipients. Methods In this prospective study, FoxP3 mRNA expression levels in peripheral blood samples from 10 recipients of living relative-donor kidney transplants were measured before transplantation as well as at the 14th and 90th days post-transplantation. In addition, 46 first-time kidney-transplant recipients participated in a cross-sectional study, with 28 patients classified as having acute organ rejection; whilst the remaining 18 patients had functionally stable allografts. FoxP3 mRNA expression levels in peripheral blood samples were compared between these two different groups. Results Before transplantation mean FoxP3 mRNA levels vs. GADPH mRNA levels （Ig（FoxP3 mRNA/GADPH mRNA）） in the 10 recipients were 1.11±0.67. The mean FoxP3 mRNA expression levels measured at 14th and 90th days post-transplantation were significantly higher than before transplantation （1.69±0.38, P=0.03; 1.44±0.21, P=0.04, respectively）. Additionally, the mean FoxP3 mRNA levels vs. GADPH mRNA expression levels （Ig（FoxP3 mRNA/GADPH mRNA）） were significantly higher in recipients suffering acute rejection compared with those with stable allografts （1.77±0.61 and 1.43±0.27, respectively, P=0.03）. Conclusions After kidney transplantntion, FoxP3 mRNA levels were found to increase in the peripheral blood of all recipients. Considerably higher FoxP3 rnRNA levels were observed in recipients suffering acute rejection. These results suggest that FoxP3 mRNA levels in peripheral blood samples can be used as a diagnostic t

关键词： kidney transplantation rejection forkhead box protein 3

The role and regulation mechanisms of APOD in prognosis and subtyping of breast cancer

在线全文

学校读者我要写书评

暂无评论

Medical Data Mining 2023年第3期6卷 39-49页

作者： Chen-Fei Zhao Shi-Liang Chen Cong Wang Dan Hu xiao-xiao yang Shi-Yuan Tong Yi-Bo He Zhe-Zhong Zhang Department of Clinical Lab The First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou310006China Department of Clinical Lab The Cixi integrated traditional Chinese and Western medicine medical and Health Group Cixi Red Cross HospitalCixi 315300China State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai 200032China

Background:Breast cancer is the most common cancer,and abnormal lipid metabolism is associated with *** expression is negatively correlated with various cancers related to tumor *** methylation may affect APOD ***,this paper aims to investigate the significance of APOD expression and APOD DNA methylation in breast ***:This study utilized comprehensive bioinformatics analysis of APOD using Gene Expression database of Normal and Tumor tissues 2,UCSC Xena,*** and survival information obtained from the The Cancer Genome Atlas and Gene Expression Omnibus datasets were extracted for data ***:The correlation between APOD and breast cancer was examined,along with the connection between APOD DNA methylation and APOD *** the The Cancer Genome Atlas cohort,as well as GSE31448 and GSE65194 datasets,APOD expression decreased in breast cancer(P<0.0001).Clinical feature analysis results showed that APOD expression was correlated with the PAM50 subtype,with the lowest expression in the Basal subtype(P<0.0001).High APOD expression is a good prognostic marker for breast cancer(HR=0.71,P=0.037).APOD methylation level was significantly negatively correlated with expression level(R=−0.4770,P<0.001),and cg15231202,cg23720929,and cg05624196 were important regulatory *** APOD expression was associated with higher metabolism and extracellular matrix ***:APOD is an independent prognostic marker for breast cancer and is regulated by DNA methylation to modulate mRNA expression.

关键词： breast cancer APOD DNA methylation bioinformatics prognosis PAM50 subtype

DETERMINATION　OF　PROTEIN　USING　CATALYTIC　COLORIMETRY　OF　SULFANILIC　ACID　BY　COBALT（Ⅱ）

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1994年第12期5卷 1037-1038页

作者： Yun Xiang CI xiao Da yang and xiao Ting TANG(Department of Chemistry. Peking University. Beijing, 100871)

A new protein analysis method by the use of sulfanilic acid-hydrogen peroxide(H2O2)-Co2+ system was described. The method was based on the inhibition effect of protein on the catalytic activity of Co2+ for the coloration of sulfanilic acid. It took advantages of rather mild assay condition(pH 9.0), similar responses for albumin and globulin, and little interference. The assay could have a dynamic range of 0-1.00 mg/mL with a detection limit of about 0.01 mg/mL.

关键词： ACID SULFANILIC COBALT BY CATALYTIC

Highly conductive and stable iodine doped argyrodite electrolyte for all-solid-state lithium batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 50-58页

作者： Gaozhan Liu Jing Zhang Jing yang Jinghui Chen Xingyue xiao Xiayin Yao Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Lithium argyrodites with high ionic conductivity and low cost are considered as one of the most prospective solid electrolytes for all-solid-state lithium ***,the poor chemical stability and compatibility with lithium metal limit their ***,Li5.4PS4.4Cl1.4I0.2solid electrolyte with high ionic conductivity of 11.49 m S cm-1and improved chemical stability is synthesized by iodine *** ultra-thin Li5.4PS4.4Cl1.4I0.2membrane with thickness of 10μm can be obtained by wet coating process,exhibiting a high ionic conductivity of 2.09 mS cm-1and low areal resistance of 1.17Ω***,iodine doping could in-situ form LiI at the lithium/electrolyte interface and improve the critical current density of Li5.4PS4.4Cl1.6from 0.8 to 1.35 mA *** resultant LiCoO2/Li5.4PS4.4Cl1.4I0.2/Li battery shows excellent cycling stability at 1 C,with a reversible specific capacity of 110.1 mA h g-1and a retention of 80.5% after 1000 *** addition,the assembled LiCoO2/Li5.4PS4.4Cl1.4I0.2membrane/Li pouch cell delivers an initial discharge capacity of 110.4 mA h g-1and 80.5% capacity retention after 100 cycles.

关键词： Solid-State Batteries