沈阳肾脏解剖模型(贵州综合修复体) (今日更新中)

BEIJING, Oct. 13 (Xinhuanet) -- Tyrannosaurus rex dinosaur, the giant prehistoric predator, was even bigger and heavier than it was estimated previously, a new study found.The finding was contained in a study published Wednesday in the scientific journal PLoS ONE.Using three-dimension scanning and computer modeling, researchers analyzed five skeleton fossils of T. rex dinosaur, including "Sue", the largest and most complete T. rex specimen ever found.The analysis tipped the scale of "Sue" at 9 ton, some 30 percent more than it was expected."At their fastest, in their teenage years, they were putting on 11 pounds or 5 kilograms a day," said John Hutchinson of the Royal Veterinary College in London, who co-led the study.The larger body mass indicated the better agility and the stronger lower-leg muscles of the ancient monster, said the researcher."Sue" could have a top speed of about 10-25 miles per hour when it ran on the Great Plains of North America 67 million years ago, Hutchinson suggested.

WASHINGTON, Nov. 24 (Xinhua) -- An inexpensive drug that treats Type 2 diabetes has been shown to prevent a number of natural and man-made chemicals from stimulating the growth of breast cancer cells, according to a newly published study by a Michigan State University researcher. The research, led by pediatrics professor James Trosko and colleagues from South Korea's Seoul National University, provides biological evidence for previously reported epidemiological surveys that long-term use of the drug metformin for Type 2 diabetes reduces the risk of diabetes-associated cancers, such as breast cancers.The research appeared online this week in PLoS One.For the study, Trosko and colleagues focused on the concept that cancers originate from adult human stem cells and that there are many natural and man-made chemicals that enhance the growth of breast cancer cells. Using culture dishes, they grew miniature human breast tumors, or mammospheres, that activated a certain stem cell gene. Then the mammospheres were exposed to natural estrogen -- a known growth factor and potential breast tumor promoter -- and man-made chemicals that are known to promote tumors or disrupt the endocrine system.The team found that estrogen and the chemicals caused the mammospheres to increase in numbers and size. However, with metformin added, the numbers and size of the mammospheres were dramatically reduced. While each of the chemicals enhanced growth by different means, metformin seemed to be able to inhibit their stimulated growth in all cases."While future studies are needed to understand the exact mechanism by which metformin works to reduce the growth of breast cancers, this study reveals the need to determine if the drug might be used as a preventive drug and for individuals who have no indication of any existing cancers," Trosko said.

YICHANG, Oct. 30 (Xinhua) -- China's Three Gorges Dam on Sunday reached its designed highest mark, the second time for the world's largest water control and hydropower project to run at full capacity.The water level hit 175 meters at 5 p.m. after storing water for nearly two months from the water level of 152 meters, said an official with the China Three Gorges Project Corporation (CTGPC), the developer of the project.A dozen hydropower turbo-generator units started operation on Sunday, generating power capacity of 8.2 million kw, said the official.The dam in central China's Hubei Province completed its first full-capacity test last October.Operating at full capacity should give full play to the dam's functions of generating hydroelectric power, delivering water to the lower reaches to alleviate spring droughts, and containing water from summer flooding, as required by the State Flood Control and Drought Relief Headquarters.The Three Gorges Project was launched in 1993 with a budget equivalent to 22.5 billion U.S. dollars.So far, monitoring shows the dam is operating smoothly.

SAN FRANCISCO, Oct. 5 (Xinhua) -- Apple co-founder and longtime Chief Executive Officer Steve Jobs passed away on Wednesday."Steve died peacefully today surrounded by his family," Jobs' family said in a statement."We are grateful for the support and kindness of those who share our feelings for Steve. We know many of you will mourn with us, and we ask that you respect our privacy during our time of grief," said the statement.Apple's website has changed to "Steve Jobs: 1955-2011," along with the most iconic picture in which the scraggly bearded charismatic visionary posed with one hand up to his chin.Photo taken on Oct. 5, 2011 shows photo of Steve Jobs on the front page of www.apple.com. Apple Board of Directors announced that co-founder and former Chief Executive Officer Steve Jobs passed away on Wednesday"Apple has lost a visionary and creative genius, and the world has lost an amazing human being," the company said in a statement. "Those of us who have been fortunate enough to know and work with Steve have lost a dear friend and an inspiring mentor. Steve leaves behind a company that only he could have built and this spirit will forever be the foundation of Apple."Apple are asking for "thoughts, memories and condolences" to be shared by emailing rememberingsteve@apple.com.Apple Board of Directors also said in a statement that "Steve's brilliance, passion and energy were the source of countless innovations that enrich and improve all of our lives. The world is immeasurably better because of Steve."According to a memo sent by CEO Tim Cook, Apple is planning a celebration of Jobs' life for employees that will take place soon.Jobs took a medical leave of absence earlier this year, the third in his battle with pancreatic cancer that began in 2004. On Aug. 24, he stepped down as Apple CEO, saying "I have always said if there ever came a day when I could no longer meet my duties and expectations as Apple's CEO, I would be the first to let you know. Unfortunately, that day has come."Jobs recommended former CEO Tim Cook take his place as CEO. On Tuesday, Cook gave his first product announcement as CEO unveiling the new iPhone 4S.

WASHINGTON, Nov. 8 (Xinhua) -- Children with autism have more brain cells and heavier brains compared to typically developing children, according to a study to be published on Wednesday in the Journal of the American Medical Association.The small, preliminary study provides direct evidence for possible prenatal causes of autism.The prefrontal cortex is involved in various higher order functions such as language and communication, social behavior, mood, and attention. Children who have autism tend to show deficits in such functions.Eric Courchesne, of the University of San Diego School of Medicine Autism Center of Excellence, and colleagues conducted direct counts of brain cells in specific regions of the prefrontal cortex in postmortem brains of seven boys who had autism and six typically developing males, ranging in age from 2-16 years. Most participants had died in accidents, but the researchers did not base their selection on causes of death.The researchers found that children with autism had 67 percent more neurons in the prefrontal cortex and heavier brains for their age compared to typically developing children. Since these neurons are produced before birth, the study's findings suggest that faulty prenatal cell birth or maintenance may be involved in the development of autism. Another possible factor that may contribute to the neuronal excess is a reduction in apoptosis, or programmed cell death, which normally occurs during the third trimester and early postnatal life.Though small, this preliminary study examined all relevant postmortem tissue available at the time. The relative scarcity of tissue from very young children may limit future research as well, but efforts to include a larger number of samples are needed to confirm these findings and to identify patterns of age-related changes in autism, the researchers say."Earlier studies of head circumference and early brain overgrowth have pointed us in this direction, but there have been few quantitative neuroanatomical studies due to the lack of postmortem tissue from children with autism," said Thomas Insel, director of the National Institute of Mental Health, in a statement. "These new results, along with an earlier study reporting altered wiring of the prefrontal cortex, focus our attention on this critical area of the brain in autism."

来源：资阳报