伊宁早孕试纸两道杠是怀孕了吗(伊宁治疗细菌性阴道炎方法) (今日更新中)

WASHINGTON, June 16 (Xinhua) -- Cells in the human body are constantly being exposed to stress from environmental chemicals or errors in routine cellular processes. While stress can cause damage, it can also provide the stimulus for undoing the damage. New research by a team of scientists at the University of Rochester has unveiled an important new mechanism that allows cells to recognize when they are under stress and prime the DNA repair machinery to respond to the threat of damage.Their findings will be published Friday in journal Science. Cells in the human body are constantly being exposed to stress from environmental chemicals or errors in routine cellular processes. While stress can cause damage, it can also provide the stimulus for undoing the damage.The scientists, led by biologists Vera Gorbunova and Andrei Seluanov, focused on the most dangerous type of DNA damage -- double strand breaks. Unrepaired, this type of damage can lead to premature aging and cancer. They studied how oxidative stress affects efficiency of DNA repair. Oxidative stress occurs when the body is unable to neutralize the highly-reactive molecules, which are typically produced during routine cellular activities.The research team found that human cells undergoing oxidative stress synthesized more of a protein called SIRT6. By increasing SIRT6 levels, cells were able to stimulate their ability to repair double strand breaks. When the cells were treated with a drug that inactivated SIRT6, DNA repair came to a halt, thus confirming the role of SIRT6 in DNA repair. Gorbunova notes that the SIRT6 protein is structurally related to another protein, SIR2, which has been shown to extend lifespan in multiple model organisms."SIRT6 also affects DNA repair when there is no oxidative stress," explains Gorbunova. "It's just that the effect is magnified when the cells are challenged with even small amounts of oxidative stress."SIRT6 allows the cells to be economical with their resources, priming the repair enzymes only when there is damage that needs to be repaired. Thus SIRT6 may be a master regulator that coordinates stress and DNA repair activities, according to Gorbunova.

CAIRO, July 4 (Xinhua) -- U.S. and Italian archeologists have discovered the oldest description about an Egyptian king (about 3, 200 BC) in Egypt's Aswan, Egyptian Antiquities Minister Zahi Hawass said on Monday.The engravings "traces back to when the Egyptian language firstly recorded in hieroglyphs and tells about a unique complete royal ceremony which was known in the ancient Egyptian era," said Hawass in a statement."The pharaoh appears to be wearing the Upper Egypt crown accompanied by (Horus apostles) at the royal court, " Hawass added.Horus is one of the oldest and most significant deities in the ancient Egyptian religion and was worshipped from at least the late Predynastic period through to Greco-Roman times."This discovery is considered a supplementary one at the site unearthed near in el-Hamdulab site in northern Aswan, archaeologists said.This is one of the latest discoveries in Egypt as the surrounding wall of Betah temple (1550 BC-1070 BC) and a gate traces back to Shabaka king era were unearthed on Saturday in Luxor.

BEIJING, Sept. 4 (Xinhua) -- China's railway system has transported some 1.27 billion passengers during the first eight months of this year, up 11.8 percent from a year earlier, the Ministry of Railways said Sunday.The figure has accounted for 67.4 percent of the ministry's full-year target, said the ministry in a statement on its website.The Ministry of Railways has planned to send 1.9 billion passengers in 2011, up 13.1 percent year-on-year.The country's high-speed trains had been operating with improved order and efficiency, said the ministry, which has been required to run high-speed trains at slower speeds, as well as to reorganize bullet train schedules nationwide, for safety reasons.The State Council, or Cabinet, ordered increased safety checks after a fatal train collision that killed 40 people in July raised concerns over the safety of the country's high-speed railways.The ministry cut the number of high-speed trains running between Beijing and Shanghai to 66 pairs from 88 pairs per day, effective as of Aug. 16.Meanwhile, the railways transported more than 2.6 billion metric tons of goods from January to August, up 7.8 percent year-on-year, the ministry said.

BEIJING, June 20 (Xinhuanet) -- American Cancer Society discloses that higher education appears to be a game changer when it comes to cancer, according to foreign media reports on Sunday. The research indicates that the gap is widening in cancer death rates between college graduates and those who only went to high school .Cancer death rates for those who didn’t finish high school are almost three times higher than those of college graduates. The gap was especially wide for lung cancer, but it was also palpably large for breast, colon, and prostate cancer. For lung cancer, the death rate was five times higher among the least educated Americans than the most educated.Ahmedin Jemal, ACS Vice President of Surveillance Research, said that higher smoking and obesity rates among lower-income Americans combined with less access to medical services mainly expounds the disparity.Researchers concluded that bridging the education-socioeconomic gap would have prevented about 60,000 premature cancer deaths in 2007 alone in people in the 25-64 age group.

LOS ANGELES, Sept. 10 (Xinhua) -- Scientists at the University of California Los Angeles campus have announced that they have successfully used new prediction algorithms to forecast climate up to 16 months in advance.Professor Michael Ghil said in a UCLA news release Friday his team used new prediction algorithms based on matching ocean temperature records with new theories on how long-term climate trends are influenced by short-term weather extremes.That's twice as far into the future as previously accomplished.Ghil, a distinguished professor of climate dynamics in the UCLA Department of Atmospheric and Oceanic Sciences and senior author of the research, said the new prediction formulas will give climate experts and governments clues about long-term swings in the El Nino/La Nina oscillation in the Pacific Ocean, which drastically affects weather in the Americas, Asia and Australia.The new forecasting tool uses sea temperatures and has been tested on decades of historical data. The forecasts were then cross-checked against actual climate trends.The UCLA team also said that their 16-month forecasts were more accurate than previous forecasts that went only 8 months forward.Ghil emphasized that the forecasting tools are for climate, which is long-range, global patterns, but not for meteorology, which is short-term weather forecasting."Certain climate features might be predictable, although not in such detail as the temperature and whether it will rain in Los Angeles on such a day two years from now," said Ghil, who is also a member of UCLA's Institute of Geophysics and Planetary Physics. "These are averages over larger areas and longer time spans."The study is currently available online in the journal Proceedings of the National Academy of Sciences (PNAS) and will be published in an upcoming print edition of the journal.

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