中山市有哪些脱肛医院(中山便血可能是怎么回事) (今日更新中)

WASHINGTON, Oct. 13 (Xinhua) -- U.S. researchers have corrected sickle cell disease in adult laboratory mice that had been bred to have the inherited blood disorder by activating production of a special blood component, according to a study published online Thursday in the journal Science.Sickle cell disease results from an abnormality in hemoglobin, the protein found in red blood cells that is responsible for transporting oxygen throughout the body. People living with sickle cell disease have two copies of an altered gene that produces sickle hemoglobin instead of normal adult hemoglobin. Sickle hemoglobin changes shape after releasing its oxygen, causing the red blood cell to become stiff, misshapen and sticky, and slowing blood flow to tissues. This process damages organs and causes pain.The study tested a new approach to increasing the production of a third form of hemoglobin -- fetal hemoglobin. Production of fetal hemoglobin predominates before birth, but turns off thereafter as adult hemoglobin production takes over. People with sickle cell disease are unable to make normal adult hemoglobin, and instead make sickle hemoglobin starting in infancy.An elevated level of fetal hemoglobin within the red blood cell reduces the tendency of sickle hemoglobin to change the shape of red blood cells. Considerable research has shown that the drug hydroxyurea increases production of fetal hemoglobin and reduces the number of pain crises and other complications of sickle cell disease in adults and children. However, not all patients respond well to hydroxyurea, and adverse side effects are a concern.The current study explores a more targeted approach to increasing fetal hemoglobin production. It builds upon earlier studies that discovered a protein called BCL11A normally suppresses the production of fetal hemoglobin soon after birth. The researchers viewed the BCL11A protein as a target for therapy and decided to see what would happen if they blocked production of the protein.The paper details how the research team silenced the mouse gene that produces the BCL11A protein in mice with sickle cell disease. Silencing the gene turned off production of the BCL11A protein and allowed the adult mice to continue to produce fetal hemoglobin. It appears to have eliminated disease symptoms without affecting other aspects of blood production."This discovery provides an important new target for future therapies in people with sickle cell disease," said Susan Shurin, acting director of the U.S. National Heart, Lung, and Blood Institute, which co-funded the study. "More work is needed before it will be possible to test such therapies in people, but this study demonstrates that the approach works in principle."Approximately 100,000 Americans live with sickle cell disease. It is most prevalent in people of African, Hispanic, Mediterranean, and Middle Eastern descent. There is no widely available cure for sickle cell disease. Bone marrow transplants have cured some patients, but the treatment is not without risk and most patients do not have relatives who can donate compatible and healthy bone marrow to them.

WASHINGTON, Dec. 7 (Xinhua) -- Drugs that affect the levels of an important brain protein involved in learning and memory reverse cellular changes in the brain seen during aging, according to an animal study published Wednesday in the Journal of Neuroscience. The findings could one day aid in the development of new drugs that enhance cognitive function in older adults.Aging-related memory loss is associated with the gradual deterioration of the structure and function of synapses (the connections between brain cells) in brain regions critical to learning and memory, such as the hippocampus.Recent studies suggested that histone acetylation, a chemical process that controls whether genes are turned on, affects this process. Specifically, it affects brain cells' ability to alter the strength and structure of their connections for information storage, a process known as synaptic plasticity, which is a cellular signature of memory.In the current study, Cui-Wei Xie, of the University of California, Los Angeles, and colleagues found that compared with younger rats, hippocampi from older rats have less brain-derived neurotrophic factor (BDNF) -- a protein that promotes synaptic plasticity -- and less histone acetylation of the Bdnf gene. By treating the hippocampal tissue from older animals with a drug that increased histone acetylation, they were able to restore BDNF production and synaptic plasticity to levels found in younger animals."These findings shed light on why synapses become less efficient and more vulnerable to impairment during aging," said Xie, who led the study. "Such knowledge could help develop new drugs for cognitive aging and aging-related neurodegenerative diseases, such as Alzheimer's disease," she added.

BEIJING, Oct. 21 (Xinhuanet) -- A team of European researchers announced that they have found vast water vapor out of our solar system, according to a study in the U.S. journal Science Friday.Using Herschel Space Observatory, a European Space Agency satellite, the researchers observed that the vast water vapor enveloped a 175-light-year-away star and its surrounding dusk disk, which will eventually form a planet.The water vapor, which is "enough to fill thousand of Earth ocean", may rain down and seed the future oceans on the young planet, as it did on the Earth 4.5 billion years ago, the researchers suggested."Scientists have long suspected there were these reservoir of cold water hiding in the outer regions of planet disk, ... now the theory gets considerably stronger." said astronomer Michiel Hogerheijde of Leiden Observatory in the Netherlands.The finding not only explained where our Earth's ocean came from, but also indicated that there are likely to be many "ocean worlds" throughout the galaxies, he concluded.

SAN FRANCISCO, Oct. 5 (Xinhua) -- Microsoft announced Wednesday that it will bring cable television content to its Xbox video game console over the upcoming holiday season, expanding the console into an entertainment hub.According to the company's press release, nearly 40 world- leading TV and entertainment providers such as HBO GO and BBC will stream their content through the Xbox Live service in more than 20 countries and regions.Users will be able to sift through shows online with the Kinect motion sensor device for Xbox 360 and Bing voice search, Microsoft said.To watch TV programs via Xbox as an alternate delivery system, customers have to already subscribe to the TV services and Microsoft's Xbox Live Gold service of 60 U.S. dollars per year."Today's announcement is a major step toward realizing our vision to bring you all the entertainment you want, shared with the people you care about, made easy," Microsoft said in the press release.Microsoft first entered the gaming console market in 2001 with the Xbox, the predecessor to the Xbox 360. The Xbox 360 currently competes with Sony's PlayStation 3 and Nintendo's Wii as the seventh generation of video game consoles.In June, Microsoft said 35 million people subscribed Xbox Live service around the world, spending an average of 60 hours a month playing games and watching movies and shows. Last year, the company integrated social networking features into Xbox Live, allowing users chat with each other while watching programs.

SAN FRANCISCO, Dec. 9 (Xinhua) -- Apple on Friday suffered a major setback in its global patent war, as a German court ruled over its copyright infringement battle in favor of Motorola Mobility.The German court ruled that Apple's iPhone and iPad infringe a Motorola patent and issued an injunction banning the import of iPhones and 3G-capable iPads into Germany.The dispute, one of Apple's several patent lawsuits around the world, is over a Motorola patent essential to GPRS. Motorola has been negotiating with Apple over licensing terms and conditions since 2007, and it will continue its efforts to resolve its global patent dispute as soon as practicable, said Motorola Mobility in a statement on Friday."We're going to appeal the court's ruling right away. Holiday shoppers in Germany should have no problem finding the iPad or iPhone they want," an Apple spokesman told tech news site AllThingsD.Apple is not too concerned about losing out in the Christmas shopping season as it has plenty of iPhones and iPads in Germany already, AllThingsD cited unidentified sources as saying.The ruling is against Apple's European sales company and only impacts its products sold in Germany. The German court also ruled that Motorola is entitled to a damages award.Apple can appeal the ruling to a higher court and request a stay of the injunction, according to a blog post of Florian Mueller, a U.S. patent expert who has been closely following patent lawsuits in the mobile industry.Mueller said should Apple make the appeal but the court declines the stay, Motorola must post a 100 million euro (around 134 million U.S. dollars) bond before the court will enforce the injunction.In August, Apple also filed a suit in Germany over the design of Motorola's tablet Xoom, which runs Google's Android system. But Apple did not make it clear whether it will seek to block the sales of Xoom in Europe.Also on Friday, Samsung won an appeal from the Australian High Court overturning a previous Apple victory that effectively banned Samsung from selling its Galaxy Tab in Australia.Based on claims of infringing Apple's patents, the Cupertino, California-based tech giant has been seeking court order to block Samsung's Galaxy line of mobile devices around the world.A German court issued an injunction in August, blocking Samsung from selling its Galaxy Tab 10.1 tablets across all European Union members, except for the Netherlands.On Thursday, Apple said it will appeal a San Jose, California judge's refusal to ban sales of Samsung 4G smartphones and Galaxy Tab 10.1 tablets in the United States.

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