濮阳东方男科医院收费与服务(濮阳东方医院妇科在线挂号) (今日更新中)

WASHINGTON, Aug. 4 (Xinhua) -- U.S. scientists have found two gene mutations occurring in oligodendrogliomas, the second-most common form of brain cancer, according to a study to be published Friday in journal Science.For years scientists have been looking for the primary cancer genes involved in oligodendrogliomas evolvement. Scientists know the two chromosomes held the probable mutations, but the particular gene information remains unclear.Now scientists at Duke University Medical Center and Johns Hopkins University have discovered the most likely genetic mutations that researchers have been hunting for on chromosomes 1 and 19.The genes they identified, CIC or FUBP1, are tumor suppressor genes. The cancer-related pathways that involve these genes could become targets for future treatments, said Hai Yan, a Duke associate professor of pathology and co-corresponding author of the study.The researchers found CIC on chromosome 19 and FUBP1 on chromosome 1 based on an initial study of seven oligodendrogliomas. They found six mutations and two mutations, respectively, in the seven tumors. Further study of 27 more of these tumors showed that there were 12 and three mutations of CIC and FUBP1, respectively. The two genes were rarely mutated in other types of cancers, indicating that they are oligodendroglioma-specific genes.These genes were difficult to find until the technology improved, said Yan."The team used whole genome sequencing technology so that no genes would be excluded, and we found to our surprise that one gene, on chromosome 19, was mutated in six out of the seven initial tumor specimens we sequenced," Yan said. "A mutation frequency of 85 percent is very high."The finding of two additional new genes involved in oligodendrogliomas increases the chances for an effective combination drug therapy for the tumor, Yan said. He envisions a combination cocktail of drugs similar to the combination-drug treatments taken by HIV patients that would target different pathways involved in cancer, and assist both in reducing the chance of relapsing and increasing odds of success.

BEIJING, Sept. 2 (Xinhuanet) -- The amount of space junk orbiting the Earth could cause fatal leaks in spaceships or destroy valuable satellites, according to a report released by the U.S. National Research Council.Computer models have shown that the number of orbital debris "has reached a tipping point, with enough currently in orbit to continually collide and create even more debris, raising the risk of spacecraft failures," the Research Council said Thursday.So far, there are 22,000 pieces of debris large enough to track from the ground, but smaller objects could still cause serious damage.New international regulations are needed to limit space junk.And more researches should be done to test the possible use of launching magnetic nets or giant umbrellas to push the debris further towards the Earth where it would burn up, or into a higher but safer orbit.

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.

BEIJING, Sept. 2 (Xinhuanet) -- The amount of space junk orbiting the Earth could cause fatal leaks in spaceships or destroy valuable satellites, according to a report released by the U.S. National Research Council.Computer models have shown that the number of orbital debris "has reached a tipping point, with enough currently in orbit to continually collide and create even more debris, raising the risk of spacecraft failures," the Research Council said Thursday.So far, there are 22,000 pieces of debris large enough to track from the ground, but smaller objects could still cause serious damage.New international regulations are needed to limit space junk.And more researches should be done to test the possible use of launching magnetic nets or giant umbrellas to push the debris further towards the Earth where it would burn up, or into a higher but safer orbit.

BEIJING, Sept. 24 (Xinhuanet) -- The city government called on residents to register their dogs on time and keep better control of them to fight the increasing number of rabies cases during a discussion of the Beijing Municipal People's Congress on Friday."As the number of dogs in the city rises, the number of dog bites is also going up," said Lei Decai, director of the rural affairs committee of the people's congress.Last year, more than 30,000 residents were bitten by dogs and nine died of rabies. As of June this year, six people have died of rabies, Lei said."The main problem lies in the registration of dogs," he said, adding that the number of unlicensed dogs in the city is unknown. A man takes his dog for a spin on the back of a motorized tricycle in a Beijing street last month. The city plans to strengthen management of dogs in the future in an effort to combat the spread of rabies, which can be fatal if it is not treated in timeAt the beginning of June, eight residents were attacked by dogs in Beijing's Olympic Forest Park.One of them, Zhao Haiyan, 56, a retiree, was bitten in her left leg as she walked in the park. The puncture wounds left her leg bleeding."An officer in the park brought me to a hospital to get vaccinated for rabies, and I had no idea who I could ask for compensation, because the dog was fed by workers in a construction site and had no registration," she told China Daily."Now I worry when I see an unleashed dog," she added.Zhao is not alone. Cao Lifang, also 56, has helped a friend care for a dog since February. Dabai, a 6-year-old male Samoyed, bit her in mid-June when she was trying to keep him from fighting another dog.The attack left a deep bite mark on Cao's left hand, and she had to take anti-rabies injections for more than a month.

来源：资阳报