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The mystery is solved--CatSper is the principal calcium channel activated by progesterone in human spermatozoa

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Asian Journal of Andrology 2011年第3期13卷 351-352页

作者： Christopher lr Barratt Reproductive and Developmental Biology Maternal and Child Health Science Laboratories Centre for Oncology and Molecular Medicine Ninewells Hospital University of Dundee Dundee Scotland DD1 9SY UK

Aremarkable advance in sperm physiology has recently been published in Nature. Two groups using patch damping techniques on human sperm have solved a mystery about the sperm cell that has puzzled both andrologists and those involved in non-genomic cellular signalling for over 20 years. In these papers, Lishko1 and Strunker2 independently demonstrate that the universal characteristic effect of progesterone on sperm--a rapid influx of calcium--is via a sperm-specific channel CatSper.

关键词： Biological sciences Cancer Medical research

Optimal sensitivity perturbation analyses on persistent anomalous summer circulation in East Asia

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Chinese Science Bulletin 1997年第8期42卷 673-678页

作者： Yang, Y Ji, lr Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

THE blocking high over Ural and Okhotsk Sea in mid- and high latitudes and the western Pa-cific subtropical high(SH)are the major components of the East Asian summer monsoon *** persistent anomalies may lead to severe... 详细信息

关键词： adjoint sensitivity analysis optimal sensitivity perturbation persistent anomaly East Asian summer monsoon.

Potential roles of tumor suppressor genes and microsatellite instability in hepatocellular carcinogenesis in southern African blacks

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World Journal of Gastroenterology 2000年第1期6卷 37-41页

作者： Roberts lr LaRusso NF Division of Gastroenterology and Hepatology Department of MedicineMayo Medical SchoolClinic and FoundationRochesterMN 55905USA

MAJOR POINTS OF THE COMMENTED ARTICLECumulative loss of heterozygosity(LOH)ofchromosomal regions and tumor suppressor geneshas been reported in hepatocellular carcinomas(HCCs) from China,Japan,and *** thisissue of the World Journal of Gastroenterology,Martins et al report an analysis of LOH andmicrosatellite instability in HCCs from a group of

关键词： Subject headings liver neoplasms carcinoma hepatocellular tumor supressor gene microsatellite instability

Fluorescence Quenching and Depolarization Studies on Segmental Motion of Poly (N, N-dimethylacrylamide)

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Chinese Chemical Letters 1997年第8期8卷 719-720页

作者： Zhu, CY Wu, SH Li, lr NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

A new polymer, poly(N, N-dimethylacrylamide), labeled with acenaphthylene has been synthesized. The rotational relaxation time of this polymer has been studied using steady state fluorescence depolarization measuremen... 详细信息

关键词： Fluorescence Quenching and Depolarization Studies on Segmental Motion of Poly N-dimethylacrylamide

Structure Investigation of Poly(vinyl alcohol)-Collagen Composite

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Journal of Materials Science & Technology 1997年第3期13卷 179-183页

作者： Zhang, QQ Ren, L Liu, lr Wang, C UNIV UTAH CCCDSALT LAKE CITYUT 84112

Naturally derived collagen protein was mixed thoroughly with medical grade poly (vinyl alcohol) (PVA) at the ratio of 90:10 (w/w) and was crosslinked by formaldehyde to form a homogeneous composite membrane. The bulk structure of the membrane was characterized by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). The membrane surface structure was investigated using Fourier transform-infrared spectroscopy (attenuated total refraction) (FTIR-ATR), electron spectroscopy for chemical analysis (ESCA) and contact angle measurement. It was found that collagen and PVA can remain stable. This was supported by the fact that no sign of phase separation had been observed. The use of crosslinking agent can substantially influence the structure of the composite. It is suggested that this new composite deserves further investigation and is potentially usable as a biomedical material.

关键词： Nonmetallic matrix composites

Thermal Properties of PHB/PEG Blends

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Journal of Materials Science & Technology 1998年第1期14卷 95-96页

作者： Zhang, QQ Zhang, Y Wang, FJ Liu, lr Wang, C Chinese Acad Med Sci Inst Biomat Engn Tianjin 300192 Peoples R China Peking Union Med Coll Tianjin 300192 Peoples R China Univ Utah Salt Lake City UT 84112 USA

Thermal properties of PHB and PHB/PEG blends were investigated by differential scanning calorimetry (DSC) and melt index (MI) test. DSC thermograms indicate that two components of blend are miscible. From the DSC thermogram, we can also conclude that the melting point of PHB descends with the increased content of PEG, this can improve PHB processing properties. From MI data, we may draw the same conclusion.

关键词： Polyesters

Calculation of latent and sensible heat fluxes during summer in ocean area around Antarctic

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Chinese Science Bulletin 1997年第7期42卷 570-573页

作者： Li, SM Zhou, MY Su, lr Lu, NP National Research Center for Marine Environmental Forecasts Beijing China

THE transfer of latent and sensible heat fluxes over the ocean surface makes an important effect on the global climatic variation. The heat fluxes can be calculated directly by using the data of fluctuations of temper... 详细信息

关键词： Antarctic heat flux marine observation.

Solid Phase In Situ Synthesis of Spin Labeled Peptide Nucleic Acid

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Chinese Chemical Letters 1997年第5期8卷 385-386页

作者： Li, XX Wang, YG Chen, YZ Zhang, lr Zhang, LH LANZHOU UNIV DEPT CHEMLANZHOU 730000PEOPLES R CHINA ZHEJIANG UNIV DEPT CHEMHANGZHOU 310027PEOPLES R CHINA BEIJING MED UNIV NATL LAB NAT & BIOMIMET DRUGSBEIJING 100083PEOPLES R CHINA

Spin labeled PNAT(10) was synthesized by solid phase method with Boc strategy. The product was characterized by ESR and TOF MS analysis revealing a facile spin labeling of PNA by in situ solid phase synthesis.

关键词： DNA

Diagnostic tools in male infertility--the question of sperm dysfunction

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Asian Journal of Andrology 2011年第1期13卷 53-58页

作者： Christopher lr Barratt Steven Mansell Catherine Beaton Steve Tardif Senga K Oxenham Reproductive and Developmental Biology Maternal and Child Health Science Laboratories Centre for Oncology and Molecular Medicine Ninewells Hospital University of Dundee Dundee DD1 9SY Scotland UK Assisted Conception Unit NHS Tavside Ninewelts Hospital. Dundee. DD1 9SY. Scotland. UK

Sperm dysfunction is the single most common cause of infertility, yet what is remarkable is that, there is no drug a man can take or add to his spermatozoa in vitroto improve fertility. One reason for the lack of progress in this area is that our understanding of the cellular and molecular workings of the mature spermatazoon is limited. However, over the last few years there has been considerable progress in our knowledge base and in addressing new methods to diagnose sperm dysfunction. We review the current state of the field and provide insights for further development. We conclude that：（i） there is little to be gained from more studies identifying/categorizing various populations of men using a basic semen assessment, where an effort is required in making sure the analysis is performed in an appropriate high quality way; （ii） technological development is likely to bring the reality of sperm function testing closer to implementation into the clinical pathways. In doing this, these assays must be robust, cheap （or more appropriately termed cost effective）, easy to use and clinically useful; and （iii） clinical necessity, e.g., the need to identify the highest quality spermatozoon for injection is driving basic research forward. This is an exciting time to be an andrologist and, likely, a fruitful one.

关键词： gamete biomarker male fertility sperm biomarker sperm dysfunction