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STUDY ON VARIATION OF SETTING AND STOPPING PRESSURES OF SAFETY VALVE WITH STRUCTURAL MODIFICATION

Chinese Journal of Mechanical Engineering 2001年第2期14卷 127-138页

作者： Lee Jinho Kwangzin Valve Industrial Co ,Ltd,korea Kim Harkbong Kim Moonsang School of Aerospace and Mechanical Engineering,Hankook Aviation university,korea 韩国光进阀门工业公司韩国韩国航空大学航空宇宙及机械工学部韩国

The possibility of pressure control with the structural change of a safety valve is investigated Safety valve is commonly used as safety devices for numerous applications which include boilers,ships,industrial plants,and piping Setting and stopping pressures of a safety valve, p set and p sto ,are traditionally adjusted with a fine tuning of seat ring and valve ring heights, h sr and h vr However, it is not easy to achieve the proper setting and stopping pressures of a safety valve in practice The depth of inside and outside grooves in a valve, d i and d o are modified and their effects on setting and stopping pressures of a safety vlave are tested The most appropriate values appear 1 0 mm in d i and 0 5～1 0 mm in d o,respectively The valve ring height, h vr ,shows that the best results can be achieved at 2 3 mm for setting pressures of 0 1～0 4 MPa and 1 0 mm for setting pressures of 0 5～1 0 MPa The stopping pressures increases with the increase of seat ring height, h sr , upto certain h sr value and then becomes independent to the seat ring height This implies that there exists the optimum h sr ,which provides the largest flow rate and the proper stopping pressure Stopping pressures of a safety valve are adjusted with the seat ring and valve ring heights This study,however,demonstrated that the modification of value grooves also changes setting and stopping pressures of a safety valve Therefore,the proper selection in dimensions of the inside and outside grooves should be considered for the safety valve design

关键词： Safety valve Compressive flow Isentropic flow theory Isentropic comressibility theory Setting pressure Stopping pressure Continuity equation Momentum equation

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Antisense Oligodeoxynucleotide Inhibits Expression of Re-com binantPorcine Follicle-Stim ulating Horm one Receptor

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Journal of Huazhong university of Science and Technology(Medical Sciences) 1999年第3期19卷 175-180页

作者： ZHU Changhong 1, Mark D. Nixon 2, WANG Yifang 1, Andrew R. LaBarbera 3 1 Center of Reproductive medicine, Tongji Hospital, Tongji Medical university, Wuhan 430030 2 Department of Obstetrics and Gynecology, university of Cincinnati college of medicine, Cincinnati, Ohio 45267 0526 3 Department of Molecular and Cellular Physiology, university of Cincinnati college of medicine, Cincinnati, Ohio 45267 0526 Center of Reproductive medicine Tongji Hospital Tongji Medical University Wuhan Department of Obstetrics and Gynecology University of Cincinnati College of Medicine Cincinnati Department of Molecular and Cellular Physiology University of Cincinnati College of Medicine Cincinnati

To assess the role of follicle stimulating hormone receptor(FSHR) gene expression in regulating expression of FSHR protein in the plasma membrane, the effects of a porcine FSHR cDNA antisense oligodeoxynucleotide (ODN) on FSHR mRNA levels and 125 I FSH binding were determined in Chinese hamster ovary cells expression recombinant porcine FSHR (pFSHR CHO cells). An 18 mer phosphorothioate endcapped antisense ODN that corresponded to the region surrounding the translation initiation codon of the porcine FSHR cDNA was synthesized. An 18 mer nonsense sequence of identical nucleotide composition, which had little homology to known DNA sequences, was synthesized for use as a control. pFSHR CHO cells were cultured in 24 well plates (10 5 cells/well) in the absence or presence of 1 20 μmol/L antisense or nonsense ODN for 24 h and then assayed for porcine FSHR mRNA, using quantitative reverse transcription and competitive polymerase chain reaction, and for 125 I FSH binding activity. Treatment with 10 μmol/L antisense ODN caused a paradoxical increase in porcine FSHR mRNA from 0.89±0.06 to 1.64±0.08 ng/mg total RNA ( P <0.05). Transfection with lipofectamine and 0.33 μmol/L antisense ODN caused an increase in porcine mRNA from 0.95±0.08 to 1.53±0.07 ng/mg total RAN. This was probably due to upregulation of mRNA synthesis resulting from inhibition of porcine FSHR protein translation. The nonsense ODN had no effect on porcine FSHR mRNA. Antisense, but not nonsense, ODN (10 μmol/L) inhibited membrane binding of 125 I FSH by 13.6± 0.8 % ( P <0.05) in 24 h. Treatment of cells with antisense ODN (10 μmol/L) for 48 h resulted in a 76±1.5 % ( P <0.05) inhibition of 125 I FSH binding. In contrast, transfection with lipofectamine and 0.33 μmol/L antisense ODN at 0 h caused a 76.1±1.3 % ( P <0.05) reduction in binding within 24 h. Binding had returned to 52.3±2.3 % ( P < 0.05) of normal by 48 h. These results indicate

关键词： follicle stimulating hormone antisense oligodeoxynucleotide folliculogenesis mRNA spermatogenesis

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Anticancer effect of two diterpenoid compounds isolated from Annona glabra Linn

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Acta Pharmacologica Sinica 2004年第7期25卷 91-96页

作者： Yong-hong ZHANG2, Hai-yan PENG3, Guo-hao XIA3, Ming-yan WANG3, Ying HAN4 First Clinical college 3Basic medicine college, Nanjing university of TraditionalChinese medicine, Nanjing 210029 4Jiangsu Institute of Materia Medica, Nanjing 210009, China First Clinical college，Nanjing university of Traditional Chinese medicine Nanjing 210009 Basic medicine college Nanjing University of Traditional Chinese Medicine Nanjing 210029 Jiangsu Institute of Materia Medica Nanjing 210009

AIM: To study the inhibitory effect of two diterpenoid compounds isolated from Annona glabra Linn (Cunabic acid and ent-kauran-19-al-17-oic acid) on the proliferation of Human Liver Cancer (HLC) cell line SMMC-7721 and its mechanism. METHODS: Inhibition of cell proliferation was measured by MTT assay. The morphological changes of SMMC-7721 cells were observed under inverted phase-contrast microscope, fluorescent microscope, transmission electron microscope (TEM), and scanning electron microscope (SEM). Flow cytometer (FCM) was used to calculate the cell apoptotic rate, and immunohistochemical staining was used to observe the regulation of gene expression. RESULTS: The proliferation of SMMC-7721 cells was obviously inhibited after being treated with Cunabic acid at the concentration >5 μmol/L and ent-kauran-19-al-17-oic acid >10 μmol/L. The biggest inhibitory effect was 81.05 % when treated with Cunabic acid at the concentration of 25 μmol/L. The effect had a linear relationship with concentration. The result indicated that drug-treated cells exhibit typical morphological changes of apoptosis, including condensed chromatin and a reduction in volume. Sub-G0/G1 peak was found by FCM analysis and the cell cycle was arrested at G0/G1 stage. The apoptotic rates of the cells treated by Cunabic acid and ent-kauran-19-al-17-oic acid were 43.31 % and 24.95 %, respectively. It was visualized by immunohis- tochemical staining that the drugs down-regulated the gene expression of bcl-2 gene and up-regulated that of bax gene. CONCLUSION: The two diterpenoid compounds isolated from Annona glabra Linn, Cunabic acid and ent- kauran-19-al-17-oic acid can obviously inhibit the proliferation of HLC cell line SMMC-7721. The mechanism is correlated with the induction of cell apoptosis by down-regulating the gene expression of bcl-2 gene and up- regulating that of bax gene.

关键词： Annona glabra Linn diterpenes hepatocellular carcinoma apoptosis gene expression

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A new pteridinedione from Whitmania pigra

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Chinese Chemical Letters 2010年第5期21卷 603-605页

作者： Yun Feng Zheng,Cun Yu Li,Guo Ping Peng,Hong Yang Li college of Pharmacy,Nanjing university of Chinese medicine,Nanjing 210046,China college of Pharmacy Nanjing University of Chinese Medicine Nanjing 210046 China

A new compound,6-methylsulfinylthieno[3,2-g]-2,4(1H,3H)-pteridinedione,was isolated from the water extract of Whitmania pigra *** structure was elucidated on the basis of NMR and ESIMS spectra.

关键词： Whitmania pigra Heterocycle 6-Methylsulfinylthieno[3,2-g]-2,4(1H,3H)-pteridinedione

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Potentiation of apomorphine effect on sildenafil-induced penile erection in conscious rabbits

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Asian Journal of Andrology 2004年第3期6卷 205-209页

作者： Jae-Young Park Hwancheol Son Soo Woong Kim Jae-Seung Paick Department of Urology Seoul National University College of MedicineSeoulKoreaDepartment of UrologySeoul Municipal Boramae HospitalSeoulKoreaDepartment of UrologySeoul National University College of MedicineSeoulKoreaDepartment of UrologySeoul National University College of MedicineSeoulKorea

Aim: To investigate a possible potentiation effect of apomorphine (APO) on sildenafil-induced penile erection in the conscious rabbit. Methods: Erection of male New Zealand White rabbits (3.5-4.0 kg, n=12) was assessed by measuring the length of the uncovered penile mucosa and the duration of erection before and after intravenous administration of agents. After injection of APO (0, 0.05, 0.1 and 0.4 mg/kg), sildenafil was administered intravenously in a dose-response manner (0.5, 1 and 5 mg/kg). In additional experiments, the effect of increasing doses of sildenafil in combination with APO on systemic blood pressure was evaluated. Results: Systemic administration of sildenafil induced a dose-dependent increase in the penile length. Intravenous injection of APO alone did not produce any change in the penile length, while significantly enhanced the penile erection induced by sildenafil. The co-administration of 0.1 mg/kg of APO and 1 mg/kg of sildenafil was found to be the most effective combination in producing penile erection. Intravenous administration of sildenafil caused a concentration-dependent decrease in systemic blood pressure, but no additional decrease was observed with co-administration of APO. Conclusion: APO enhances the penile erection induced by sildenafil in the conscious rabbit without causing an additional decrease in blood pressure.

关键词： penile erection sildenafil apomorphine conscious rabbit combination therapy

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Synthesis and anticonvulsant activity of 7-benzylamino-4,5-dihydro-[1,2,4] triazolo[4,3-a] quinolines

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Progress in Natural Science:Materials International 2007年第9期17卷 1104-1108页

作者： Cui Xiangshu1,2,Guan Liping3,Li Hailan3,Piao Huri3 and Quan Zheshan1,3(1.Key Laboratory of Organic Functional Factors of the Changbai Mountain,Ministry of Education,Yanbian university,Yanji 133002,China 2.college of Basic medicine,Yanbian university,Yanji 133000,China 3.college of Pharmacy,Yanbian university,Yanji 133000,China) Key Laboratory of Organic Functional Factors of the Changbai Mountain Ministry of Education Yanbian University Yanji 133002 China college of Basic medicine Yanbian University Yanji 133000 China college of Pharmacy Yanbian University Yanji 133000 China

A series of 7-substituted-benzylamino-4,5-dihydro-[1,2,4]triazolo[4,3-a]quinoline derivatives was synthesized and evaluated for their anticonvulsant *** subcutaneous pentylenetetrazole test(sc-PTZ)demonstrated that the most effective compound in controlling the sc-PTZ induced seizure was 7-(3-bromine-benzylamino)-4,5-dihydro-[1,2,4]triazolo[4,3-a]quinoline(4j)with an ED50 of 5.0 mg/kg and the PI of 20.7,which was also safer than the reference *** the maximal electroshock test(MES)demonstrated that among these derivatives,7-(3-fluorobenzylamino)-4,5-dihydro-[1,2,4]trizolo[4,3-a]quinoline(4i),with an ED50 of 15.3 mg/kg and the PI of 7.2,was the safest in MES ***,their neurotoxicities were measured by the rotarod neurotoxicity test,and the results showed that all derivatives possessed lower neurotoxicity.

关键词： quinoline triazole synthesis anticonvulsant epilepsia

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ON THE LEAST SQUARES PROBLEM OF A MATRIXEQUATION

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Journal of Computational Mathematics 1999年第6期17卷 589-594页

作者： An-ping Liao(college of Science, Hunan Normal university, Changsha 410081, China) 湖南师范大学理学院湖南长沙 410081

Least squares solution of F=PG with respect to positive semidefinite symmetric P is considered,a new necessary and sufficient condition for solvablity is given,and the expression of solution is derived in the some special cases. Based on the expression, the least spuares solution of an inverse eigenvalue problem for positive semidefinite symmetric matrices is also given.

关键词： least squares solution matrix equation inverse eigenvalue problem positive semidefinite symmetric matrix

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The Qa-1 Dependent CD8^+ T Cell Mediated Regulatory Pathway

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Cellular & Molecular Immunology 2005年第3期2卷 161-167页

作者： Hong Jiang~(1,2) ~1Department of medicine,Division of Rheumatology,college of Physicians & Surgeons,Columbia university,USA ~2Corresponding to:Dr.Hong Jiang,Department of medicine,Division of Rheumatology,college of Physicians & Surgeons,Columbia university,630 W.168th Street,PH 8-E Ste.101,New York,NY 10032,USA. Department of medicine Division of Rheumatology College of Physicians & Surgeons Columbia University New York NY 10032 USA. HJ4@columbia.edu

The immune system has evolved a variety of regulatory mechanisms to ensure the peripheral self-tolerance as well as the optimal capacity to elicit effective anti-infection immunity. At present, there is no satisfactory conceptual framework to explain how the peripheral immunity is regulated at a biological system level, which enables the immune system to perform its essential functions to mount effective immunity to virtually any foreign antigens but avoid harmful immune responses to self. In this regard, during the past few years, an “affinity/avidity model of peripheral T cell regulation” has been proposed and tested, which opens up a new paradigm to understand how the peripheral immunity, to both self and foreign antigens, is regulated. The paradigm is based on the discovery of a subset CD8^＋ T cells with TCRs which specifically recognize a unique set of self-peptides presented by the MHC class Ib molecule Qa-I differentially expressed on T cells as a function of the affinity/avidity of T cell activation. These Qa-1 restricted CD8^＋ T cells represent an example of how the immune system utilizes a unified mechanism to regulate adaptive immunity to both self and foreign antigens. Thus, by selectively down-regulating T cells of intermediate affinity/avidity, to any antigens, the immune system controls the adaptive immunity without the necessity to distinguish self from non-self in the periphery at the level of T cell regulation. Cellular ＆ Molecular Immunology. 2005;2（3）：161-167.

关键词： T cell regulation CD8^+ T cell affinity/avidity Qa- 1 TCR

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Taurine Inhibits Myocardial Fibrosis via PKC-ERK1/2 Signaling Pathways

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Chemical Research in Chinese Universities 2012年第1期28卷 84-90页

作者： WANG Li-ying1,2, LI Hong1 and YANG Shi-jie1 1. Department of Pharmacology, Norman Bethune college of medicine, Jilin university, Changchun 130021, P. R. China 2. Department of Physiology, Basic medicine college, Beihua university, Jilin 132013, P. R. China Department of Pharmacology Norman Bethune College of Medicine Jilin University Changchun 130021

Previous studies have demonstrated the important role of taurine in inhibiting proliferation of myofibrob lasts（myoFb） and myocardial fibrosis. However, the underlying mechanisms are unclear. The present study was de signed to shed light on this issue through exploring the signal pathways via in vitro experiments. Angiotension II （AngII） treatment significantly increased myoFb proliferation and the levels of collagens I and III（P〈0.05）, whereas taurine, PKCα（PKC： protein kinase C） specific inhibitor L-threo-dihydro-sphingosine（D4681）, ERK1/2 inhibitor （PD98095） abrogated myoFb proliferation and collagen levels（P〈0.05, P〈0.01, respectively）, and increased the G0/G1 phase rate and decreased S phase rate. Immunocytochemistry, confocal fluorescence staining and image analy sis showed that taurine could inhibit the translocation and expression of p-PKCαin membrane, and then inhibit nuc lear translocation and expression of p-ERK1/2. These results have statistically significant differences compared with those of AngII group（P〈0.01）. Western blot results also show that taurine could inhibit the protein expression of p-PKCα and p-ERK1/2. We used p-PKCα specific inhibitor D4681 in order to elucidate the relationship between p-PKCα and p-ERK1/2 in signal transduction pathways. Finally, the results show that the protein expression of p-ERK1/2 and nuclear translocation were suppressed in D4681 group.

关键词： Taurine Myocardial fibrosis Proliferation Signal transduction Cardiac remodeling

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In vitro reassembly of nuclear envelopes and organelles in Xenopus egg extracts

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Cell Research 2006年第7期16卷 632-640页

作者： Ping Lu~1 Hui Zheng~2 Zhonghe Zhai ~1college of Life Sciences ~2Institute of Molecular medicine,Peking university Beijing 100871,China college of Life Sciences Peking University Beijing China Institute of Molecular medicine Peking University Beijing China

We reconstituted bilayer nuclear membranes,multilayer membranes,and organelles from mixtures of Xenopus laevis eggextracts and demembranated Xenopus sperm *** proportions of the cytosolic and vesicular fractions from theeggs were used in the reconstitution mixtures.A cytosol:vesicle ratio of 10:1 promoted reassembly of the normal bilayernuclear membrane with inserted nuclear pore complexes around the decondensed Xenopus sperm chromatin.A cytosol:vesicle ratio of 5:1 caused decondensed and dispersed sperm chromatin to be either surrounded by or divided by unusualmultilayer membrane structures with inlaid pore complexes.A cytosol:vesicle ratio of 2.5:1 promoted reconstitution ofmitochondria,endoplasmic reticulum networks,and Golgi *** reassembly of the endoplasmic reticulumand Golgi apparatus,vesicular fragments of the corresponding organelles fused together and changed their shape to formflattened cisternae,which were then stacked one on top of another.

关键词： cell-free system endoplasmic reticulum Golgi apparatus mitochondria nuclear reconstitution Xenopus egg extracts

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