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O'rand MG Widgren EE Sivashanmugam P Richardson RT Hall SH French FS VandeVoort CA Ramachandra SG Ramesh V Jagannadha Rao A 《Science (New York, N.Y.)》2004,306(5699):1189-1190
Various forms of birth control have been developed for women; however, there are currently few options for men. The development of male contraceptives that are effective, safe, and reversible is desired for family planning throughout the world. We now report contraception of male nonhuman primates (Macaca radiata) immunized with Eppin, a testis/epididymis-specific protein. Seven out of nine males (78%) developed high titers to Eppin, and all of these high-titer monkeys were infertile. Five out of seven (71%) high-anti-Eppin titer males recovered fertility when immunization was stopped. This study demonstrates that effective and reversible male immunocontraception is an attainable goal. This method of immunocontraception may be extended to humans. 相似文献
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White O Eisen JA Heidelberg JF Hickey EK Peterson JD Dodson RJ Haft DH Gwinn ML Nelson WC Richardson DL Moffat KS Qin H Jiang L Pamphile W Crosby M Shen M Vamathevan JJ Lam P McDonald L Utterback T Zalewski C Makarova KS Aravind L Daly MJ Minton KW Fleischmann RD Ketchum KA Nelson KE Salzberg S Smith HO Venter JC Fraser CM 《Science (New York, N.Y.)》1999,286(5444):1571-1577
The complete genome sequence of the radiation-resistant bacterium Deinococcus radiodurans R1 is composed of two chromosomes (2,648,638 and 412,348 base pairs), a megaplasmid (177,466 base pairs), and a small plasmid (45,704 base pairs), yielding a total genome of 3,284, 156 base pairs. Multiple components distributed on the chromosomes and megaplasmid that contribute to the ability of D. radiodurans to survive under conditions of starvation, oxidative stress, and high amounts of DNA damage were identified. Deinococcus radiodurans represents an organism in which all systems for DNA repair, DNA damage export, desiccation and starvation recovery, and genetic redundancy are present in one cell. 相似文献
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Richardson WD 《Science (New York, N.Y.)》1908,27(699):801-812
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Enkephalin-like material elevated in ventricular cerebrospinal fluid of pain patients after analgetic focal stimulation 总被引:2,自引:0,他引:2
Enkephalin-like activity has been measured in the ventricular cerebrospinal fluid of patients with intractable pain. Electrical stimulation of periventricular brain sites resulted in significant decrease in persistent pain in these subjects. This analgesia, which was blocked by naloxone in 80% of the cases, was accompanied by a significant rise in ventricular enkephalin-like activity, as measured by two different methods. The results present evidence of in vivo release of enkephalin-like material in humans and suggest that stimulation analgesia may be partially due to this release. 相似文献
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Summary Reducing sugar and sucrose content of potato tubers (cv. Record) grown in Tayside (northern United Kingdom (UK)) and Lincolnshire
(southern UK) were monitored during the 1984 growing season and after two months storage at 10°C. Neither latitude nor agronomic
factors were shown to affect sugar content. Significant correlations were found between the post storage reducing sugar content
and the sugar contents measured at harvest. Regression analyses indicated that in immature tubers sucrose breakdown was responsible
for reducing sugar accumulation during storage. 相似文献