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PARIS, Aug. 7 (Xinhua) -- European heavy-lift launcher Ariane 5 lifted off two communication satellites on Saturday.The Ariane 5, carrying Astra 1N and BSAT-3c/JCSAT-110R, was launched at 2252 GMT on Saturday from Kourou launch centre in French Guiana, according to live broadcast of the launching process.This was the fourth mission of Ariane 5 in 2011 and its 203th flight that sent off the two satellites Saturday night to their respective geostationary transfer orbits.Astra 1N, to be separated first, is built by EADS Astrium in Toulouse, France, for the Luxembourg-based operator SES Astra. With a designed lifespan of 15 years, it has an estimated liftoff mass of 5,350 kg and is fitted with 52 active Ku-band transponders.It is initially to deliver interim capacity from an orbital position of 28.2 degree East, and will subsequently move to SES Astra's prime location at 19.2 degree East for primary and backup services.BSAT-3c/JCSAT-110R is manufactured by Lockheed Martin Commercial Space Systems in Newtown, Pennsylvania, for Japanese operators B-SAT Corporation and SKY Perfect JSAT Corporation. This satellite weighs approximately 2,910 kg at launch time. It is to be positioned at 110 degree East longitude in geostationary orbit with a lifetime exceeding 16 years.This Ariane 5 flight has been postponed twice, firstly due to some technical problem in early July and then delayed by bad weather.Arianespace plans to achieve six Ariane 5 missions through this year.

WASHINGTON, May 30 (Xinhua) -- After nearly 12 days together in orbit, U.S. space shuttle Endeavour undocked from the International Space Station on Sunday night, NASA announced on Monday.According to NASA, the undocking took place at 11:55 p.m. EDT ( 0355 GMT Monday) as the spacecraft sailed 215 miles (346 km) above Bolivia.Pilot Greg Johnson, at the aft flight deck controls, flew Endeavour in a circle around the station at distances of about 450 to 650 feet. Crew members took still and video images of the station.The Space Shuttle Endeavour is seen as it departs the International Space Station after undocking in this image from NASA TV May 29, 2011.As Johnson was about to begin the flyaround, Commander Mark Kelly radioed mission control that he could see the two-billion-U. S.-dollar Alpha Magnetic Spectrometer (AMS) particle physics detector Endeavour had brought to orbit. "It's a new day for science on the space station," he said to mission control.The AMS will be left at the space station to scour the universe for clues about dark matter and antimatter. Endeavour is scheduled to land at the Kennedy Space Center at 2:35 a.m. (0635 GMT) on Wednesday.During their stay at the space station, the Endeavour crew conducted four spacewalks to complete construction of the U.S. side of the 100-billion-dollar outpost, a project of 16 nations that has been being assembled in orbit since 1998.They also brought up a logistics carrier with spare parts and performed some maintenance and installation work during the four spacewalks, the last to be carried out by an American shuttle crew.NASA plans to decommission Endeavour, its youngest shuttle with 25 voyages, and send it to a museum in Los Angeles for display.NASA's 30-year-old shuttle program is ending due to high operating costs. The Obama administration wants to spur private companies to get into the space taxi business, freeing NASA to focus on deep space exploration and new technology development.When the U.S. space shuttle program officially ends later this year, the Russian space program's Soyuz capsule will be the only method for transporting astronauts to and from the space station.

WASHINGTON, Sept. 12 (Xinhua) -- An enzyme that appears to play a role in controlling the brain's response to nicotine and alcohol in mice might be a promising target for a drug that simultaneously would treat nicotine addiction and alcohol abuse in people, U.S. researchers find.Over the course of four weeks, mice genetically engineered to lack the gene for protein kinase C (PKC) epsilon consumed less of a nicotine-containing water solution than normal mice, and were less likely to return to a chamber in which they had been given nicotine. In contrast, normal mice steadily increased their consumption of nicotine solution while the mice lacking PKC epsilon did not.The study conducted by researchers at the Ernest Gallo Clinic and Research Center, affiliated with the University of California, San Francisco, appeared Monday in the online edition of the Proceedings of the National Academy of Sciences.In normal mice, as in humans, nicotine binds to a certain class of nicotinic receptors located on dopamine neurons, which causes dopamine to be released in the brain. Dopamine creates a feeling of enjoyment, and thus prompts a sense of reward. Researchers found that mice lacking PKC epsilon are deficient in these nicotinic receptors.The finding complements earlier research in which researchers found that mice genetically engineered to lack the PKC epsilon enzyme drank less alcohol than normal mice and were disinclined to return to a chamber in which they had been given alcohol."This could mean that these mice might not get the same sense of reward from nicotine or alcohol," said Gallo senior associate director and investigator Robert Messing. "The enzyme looks like it regulates the part of the reward system that involves these nicotinic receptors."The reward system is a complex of areas in the brain that affect craving for nicotine, alcohol and other addictive substances.The next step in the research, said Messing, would be to develop compounds that inhibit PKC epsilon. The ultimate goal, he added, would be medications that could be used "to take the edge off of addiction by helping people get over some of their reward craving."

BEIJING, July 22 (Xinhuanet) -- Regulation is needed to govern rapidly expanding research in animals containing human tissue or genes, according to the Britain's Academy of Medical Sciences.Using animals with limited humanized traits is not new. Genetically engineered mice containing human DNA are already a mainstay of research into new drugs for diseases like cancer.For instance, Chinese scientists have already introduced human stem cells into goat fetuses and U.S. researchers have studied the idea of creating a mouse with human brain cells.But Martin Bobrow, a professor of medical genetics at the University of Cambridge, who led the Academy's working group, said there were three areas of particular concern."Where people begin to worry is when you get to the brain, to the germ cells, and to the sort of central features that help us recognize what is a person, like skin texture, facial shape and speech," he said.His report recommends that government should put in place a national expert body, working within the existing system for regulating animal research, to oversee such sensitive areas.British ministers said they welcomed the report and would consider its recommendations carefully.